93 results on '"Nayak NR"'
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2. Effects of luteal phase administration of mifepristone (RU486) and prostaglandin analogue or inhibitor on endometrium in the rhesus monkey.
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Nayak, NR, Ghosh, D, Sengupta, J, and Nayak, N R
- Abstract
Early luteal phase administration of a potent anti-progestin like mifepristone (RU486) inhibits blastocyst implantation and the establishment of pregnancy without marked changes in menstrual cyclicity and ovarian steroid hormone profiles; however, the underlying mechanism is not very clear. In the present study, a hypothesis that prostaglandins (PG) are involved in the anti-gestatory action of luteal phase mifepristone was tested. Endometrial changes in rhesus monkeys were examined following luteal phase administration of mifepristone, a prostaglandin synthesis inhibitor (diclofenac) and a prostaglandin analogue (misoprostol) either alone or in combination. Twenty-five monkeys were randomly assigned to six groups: group 1 (n = 4), normal control group; group 2 (n = 4), mifepristone (2 mg, daily, s.c.) treated group; group 3 (n = 4), diclofenac (25 mg daily, i.m.) treated group; group 4 (n = 4), misoprostol (100 μg, daily, oral) treated group; group 5 (n = 5), mifepristone and diclofenac (same dosages as for groups 2 and 3) treated group; group 6 (n = 4), mifepristone and misoprostol (same dosages as for groups 2 and 4) treated group. All treatments were given to monkeys on days 16-18 of mated cycles and endometrial tissue samples were collected on day 20. With diclofenac alone (group 3), marginal changes were observed in glandular, stromal and vascular compartments, and there were few apoptotic bodies in gland cells; partial inhibition and delay in implantation was earlier reported. Significantly higher oestrogen receptor expression in glandular epithelial cells as compared with all other treatment groups was found after treatment with misoprostol alone (group 4) and was associated with normal fecundity. The anti-nidatory action of luteal phase antiprogestin treatment alone or in combination with diclofenac or misoprostol was associated with altered endometrial histometric features characterized by glandular apoptosis, regression in secretory functions, decreased oedema, extravasation and a higher degree of stromal leukocytic infiltration. In these three groups (groups 2, 5 and 6) receptors for oestrogen and progesterone receptors were significantly higher in stromal cells, and lower in vascular cells, while glandular cells showed significantly higher progesterone receptors compared with the control group. The anti-nidatory activity of mifepristone and associated endometrial changes could not be accentuated or attenuated with co-administration of PGE or diclofenac, nor could these be mimicked by these agents alone. [ABSTRACT FROM PUBLISHER]
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- 1998
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3. Aberrant expression of solute carrier family transporters in placentas associated with pregnancy complications.
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Ajmeriya S, Kashyap N, Gul A, Ahirwar A, Singh S, Tripathi S, Dhar R, Nayak NR, and Karmakar S
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- Humans, Female, Pregnancy, Pregnancy Complications metabolism, Pregnancy Complications genetics, Placenta metabolism, Fetal Growth Retardation metabolism, Fetal Growth Retardation genetics, Solute Carrier Proteins metabolism, Solute Carrier Proteins genetics, Pre-Eclampsia metabolism, Pre-Eclampsia genetics
- Abstract
Introduction: Solute carrier family transporters (SLCs), crucial for nutrient and trace element uptake in the placenta, play a significant role in fetal growth and development. Their dysregulation is associated with various pregnancy disorders. However, a comprehensive understanding of their role and regulation in placental function and pregnancy complications is still a largely unexplored area, making this study novel and significant., Methods: We performed a rigorous meta-analysis of publicly available NCBI GEO microarray and RNA-Seq datasets followed by bioinformatics analysis of differentially expressed SLCs in PE and IUGR. The identified SLCs were then validated using qPCR on PE placental samples, ensuring the reliability and validity of the findings., Results: Bioinformatics analysis of preeclampsia (PE) and Intrauterine Growth restriction (IUGR) datasets revealed significant associations between specific SLC transporters with disease pathology, identified by studying differentially expressed SLCs. Subsequent validation using qPCR on placental samples confirmed considerable downregulation of SLC6A8, SLC16A10, SLC25A3, and SLC29A3, highlighting their dysregulation in the pathogenesis of PE and IUGR., Discussion: The significant downregulation of SLC6A8, SLC16A10, SLC25A3, and SLC29A3 observed by bioinformatics analyses and validated by qPCR indicates atypical expression of these SLCs in gestational disorders. Our findings underscore the potential contribution of multiple SLC gene families to the development of placental pathologies associated with diverse pregnancy complications., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2025
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4. Genetic and Epigenetic Insights into Pregnancy-Related Complications.
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Nayak NR, Srivastava A, Jena MK, Odibo A, and Sutkin G
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- Pregnancy, Humans, Female, Placenta metabolism, Placenta pathology, Epigenesis, Genetic, Pregnancy Complications genetics
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Placental dysfunction is a leading cause of numerous pregnancy complications, including preeclampsia, preterm birth, fetal growth restrictions, placental abruption, and late spontaneous abortion [...].
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- 2024
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5. Nanoquercetin based nanoformulations for triple negative breast cancer therapy and its role in overcoming drug resistance.
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Samantaray A, Pradhan D, Nayak NR, Chawla S, Behera B, Mohanty L, Bisoyi SK, and Gandhi S
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Triple Negative Breast Cancer (TNBC) is a highly aggressive and treatment-resistant subtype of breast cancer, lacking the expression of estrogen, progesterone, and HER2 receptors. Conventional chemotherapy remains the primary treatment option, but its efficacy is often compromised by the development of drug resistance. Nanoquercetin has garnered the attention of researchers due to its potential in combating cancer. This antioxidant exhibits significant efficacy against various types of cancer, including blood, breast, pancreatic, prostate, colon, and oral cancers. Functioning as a potential anti-cancer agent, nanoquercetin impedes the development and proliferation of cancer cells, induces apoptosis and autophagy, and prevents cancer cell invasion and metastasis. Numerous processes, such as the inhibition of pathways linked to angiogenesis, inflammation, and cell survival, are responsible for these anticancer actions. Moreover, it shields DNA from degradation caused by radiation and other carcinogens. The cost-effectiveness of current cancer treatments remains a significant challenge in healthcare, imposing a substantial economic burden on societies worldwide. Preclinical studies and early-phase clinical trials indicate that nanoquercetin-based therapies could offer a significant advancement in the management of TNBC, providing a foundation for future research and clinical application in overcoming drug resistance and improving patient outcomes. This article examines the latest data on nanoquercetin's potent anti-cancer properties and interprets the accumulated research findings within the framework of preventive, predictive, and personalized (3P) medicine., (© 2024. The Author(s).)
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- 2024
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6. Dendritic Cells and the Establishment of Fetomaternal Tolerance for Successful Human Pregnancy.
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Mahajan D, Kumar T, Rath PK, Sahoo AK, Mishra BP, Kumar S, Nayak NR, and Jena MK
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- Humans, Pregnancy, Female, Fetus immunology, Animals, Macrophages immunology, Pregnancy Complications immunology, Dendritic Cells immunology, Immune Tolerance, Maternal-Fetal Exchange immunology, Placenta immunology
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Pregnancy is a remarkable event where the semi-allogeneic fetus develops in the mother's uterus, despite genetic and immunological differences. The antigen handling and processing at the maternal-fetal interface during pregnancy appear to be crucial for the adaptation of the maternal immune system and for tolerance to the developing fetus and placenta. Maternal antigen-presenting cells (APCs), such as macrophages (Mφs) and dendritic cells (DCs), are present at the maternal-fetal interface throughout pregnancy and are believed to play a crucial role in this process. Despite numerous studies focusing on the significance of Mφs, there is limited knowledge regarding the contribution of DCs in fetomaternal tolerance during pregnancy, making it a relatively new and growing field of research. This review focuses on how the behavior of DCs at the maternal-fetal interface adapts to pregnancy's unique demands. Moreover, it discusses how DCs interact with other cells in the decidual leukocyte network to regulate uterine and placental homeostasis and the local maternal immune responses to the fetus. The review particularly examines the different cell lineages of DCs with specific surface markers, which have not been critically reviewed in previous publications. Additionally, it emphasizes the impact that even minor disruptions in DC functions can have on pregnancy-related complications and proposes further research into the potential therapeutic benefits of targeting DCs to manage these complications., (© 2024 Deviyani Mahajan et al., published by Sciendo.)
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- 2024
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7. Trophoblast-Targeted Liposomes for Placenta-Specific Drug Delivery.
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Zhang B, Fan X, and Nayak NR
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- Pregnancy, United States, Humans, Female, Chondroitin Sulfates, Trophoblasts, Placenta, Liposomes, Pregnancy Complications
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A major challenge in developing potential treatments for pregnancy complications is minimizing adverse effects to the fetus and mother. Placenta-targeted drug delivery could reduce the risks of drug treatments in pregnancy by targeting tissue where most pregnancy complications originate and decreasing dosages. We previously developed a tool for the targeted delivery of drug-carrying nanoparticles to the placenta using a synthetic placental chondroitin sulfate A-binding peptide (plCSA-BP) derived from the malarial protein VAR2CSA, which binds a distinct type of chondroitin sulfate A (CSA) exclusively expressed by placental trophoblasts. Liposomes are a type of nanoparticle already approved for use in humans by the Food and Drug Administration (FDA) and used successfully for the treatment of a wide range of diseases. Here, we present a detailed method to create plCSA-BP-decorated liposomes that can be used to deliver drugs specifically to placental trophoblasts. Liposomes are first generated by the standard film method and then conjugated to plCSA-BPs using the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysulfosuccinimide (EDC/NHS) bioconjugate technique. This protocol may facilitate bench-to-bedside translation of drug discovery for the treatment of pregnancy disorders by reducing risks of side effects, and enabling rapid and scalable production., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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8. Variable Cre Recombination Efficiency in Placentas of Cyp19-Cre ROSA mT/mG Transgenic Mice.
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Anamthathmakula P, Shallie PD, Nayak N, Dhal S, Vivian JL, Mor G, Soares MJ, and Nayak NR
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- Female, Pregnancy, Male, Mice, Animals, Mice, Transgenic, Aromatase genetics, Pilot Projects, Placenta, Plant Breeding, Mosaicism
- Abstract
The aromatase-Cre recombinase (Cyp19-Cre) transgenic mouse model has been extensively used for placenta-specific gene inactivation. In a pilot study, we observed unexpected phenotypes using this mouse strain, which prompted an extensive characterization of Cyp19-Cre placental phenotypes using ROSA
mT/mG transgenic reporter mice. The two strains were mated to generate bi-transgenic Cyp19-Cre;ROSAmT/mG mice following a standard transgenic breeding scheme, and placental and fetal tissues were analyzed on embryonic day 17.5. Both maternal and paternal Cre inheritance were analyzed by mating the respective Cyp19-Cre and ROSAmT/mG males and females. The genotype results showed the expected percentage of Cyp19-Cre;ROSAmT/mG fetuses (73%) and Cre mRNA was expressed in all of the Cyp19-Cre placentas. However, surprisingly, only about 50% of the Cyp19-Cre;ROSAmT/mG placentas showed Cre-mediated recombinase activity as demonstrated by placental enhanced green fluorescent protein (EGFP) expression. Further genetic excision analysis of the placentas revealed consistent results showing the absence of excision of the tdTomato in all of the Cyp19-Cre;ROSAmT/mG placentas lacking EGFP expression. Moreover, among the EGFP-expressing placentas, there was wide variability in recombination efficiency, even in placentas from the same litter, leading to a mosaic pattern of EGFP expression in different zones and cell types of the placentas. In addition, we observed a significantly higher percentage of Cre recombination activity in placentas with maternal Cre inheritance. Our results show frequent mosaicism, inconsistent recombination activity, and parent-of-origin effects in placentas from Cyp19-Cre;ROSAmT/mG mice, suggesting that tail-biopsy genotype results may not necessarily indicate the excision of floxed genes in Cyp19-Cre positive placentas. Thus, placenta-specific mutagenesis studies using the Cyp19-Cre model require extensive characterization and careful interpretation of the placental phenotypes for each floxed allele.- Published
- 2023
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9. Gene polymorphisms within regions of complement component C1q in HIV associated preeclampsia.
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Govender S, Nayak NR, Nandlal L, and Naicker T
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- Humans, Female, Pregnancy, Complement C1q genetics, Polymorphism, Single Nucleotide, Case-Control Studies, HIV Infections genetics, HIV Infections complications, Pre-Eclampsia
- Abstract
Objective: This study investigates the association of C1q gene (rs292001 and rs294183) polymorphisms in HIV infected and uninfected preeclamptic women of African ancestry., Materials and Methods: The study population consisted of 325 pregnant women of African ancestry grouped into 145 normotensive pregnant women (72 HIV uninfected normotensive, 73 HIV infected normotensive) and 180 preeclamptic pregnant women (103 HIV uninfected preeclamptics, 77 HIV infected preeclamptics). Preeclamptic pregnant women were further sub-grouped into 79 early-onset preeclampsia (EOPE) (40 HIV uninfected EOPE, 39 HIV infected EOPE) and 101 late-onset preeclampsia (LOPE) (63 HIV uninfected LOPE, 38 HIV infected LOPE). Genotyping of complement C1q gene polymorphisms (rs292001 and rs294183) was detected using a TaqMan® SNP Genotyping assay from purified DNA., Results: No significant differences in allelic and genotype frequencies of rs292001 and rs294183 between preeclamptic and normotensive women were observed. Likewise, there were no significant differences in allelic and genotype frequencies between HIV infected normotensive vs HIV infected preeclampsia and HIV uninfected normotensive vs HIV uninfected preeclampsia for both SNPs. However, the odds ratio of preeclamptic women having the GA genotype was 1:2., Conclusion: We demonstrate that SNPs of the C1q gene (rs292001 and rs294183) are not associated with the pathogenesis of PE development in women of African ancestry. The role ofC1qrs292001 heterozygous GA is highlighted (with and without HIV infection) may affect susceptibility to PE development. Notably, this dysregulation may affect C1q translation and protein output thus influencing the downstream role of the complement system and functional immunology in HIV infection comorbid with PE., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
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- 2023
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10. Molecular Mechanisms of Pregnancy-Related Vascular Remodeling and Pregnancy Complications.
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Stevenson DK, Wong RJ, and Nayak NR
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- Pregnancy, Female, Humans, Vascular Remodeling, Pregnancy Complications
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The purpose of this editorial is to highlight the various observations made in this Special Issue in the International Journal of Molecular Sciences [...].
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- 2023
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11. Stress-Sensitive Regulators of Fetal Neurodevelopment in HIV and Preeclampsia: An Immunocytochemical Appraisal of Placental OGT and T4 Levels.
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Shallie PD, Naicker T, and Nayak NR
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- Female, Pregnancy, Humans, Placenta, South Africa epidemiology, HIV Infections, Pre-Eclampsia metabolism
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Preeclampsia and HIV are a significant burden to maternal health globally, especially in low-middle income countries such as South Africa. In the KwaZulu-Natal province, SA antenatal HIV prevalence is 41.1%, while PE is 12%. PE and HIV infections are maternal stress and inflammation that impact placental function and fetal development. Therefore, this study investigated the impact of the comorbidity of PE and HIV on placental stress and neurodevelopment. Placentae were obtained from four cohorts of pregnant women: normotensive HIV negative, normotensive HIV positive, preeclamptic HIV negative, and preeclamptic HIV positive. The placental tissue sections were immunostained for OGT and T4. Our findings showed that the maternal weight, diastolic, and systolic blood pressures (BP) were higher in PE vs. the normotensive groups, irrespective of HIV status. In addition, significant changes were noticed in the placental weight, fetoplacental ratio, and placental efficiency coefficient. Our findings showed that the maternal weight, diastolic, and systolic blood pressures (BP) were statistically higher in the PE compared to the normotensive. No significant differences were observed between HIV positive and HIV negative groups. In addition, significant changes were noticed in the placental weight, fetoplacental ratio, and placental coefficient. Furthermore, considerable upregulation in the placental expression of OGT in both the conducting and exchange villi of PE and concomitant downregulation in HIV-positive patients compared with Normotensive and HIV-negative individuals, respectively. Our results provide inferential evidence on the dysregulation of OGT in the comorbidity of PE and HIV. This may mediate a compromised programmed outcome of an adverse maternal environment during pregnancy and consequently affect fetal development., (© 2023. L. Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.)
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- 2023
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12. Preserving the Privacy of Healthcare Data over Social Networks Using Machine Learning.
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Veeramakali T, Shobanadevi A, Nayak NR, Kumar S, Singhal S, and Subramanian M
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- Algorithms, Delivery of Health Care, Humans, Social Networking, Machine Learning, Privacy
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A key challenge in clinical recommendation systems is the problem of aberrant patient profiles in social networks. As a result of a person's abnormal profile, numerous vests might be used to make fake remarks about them, cyber bullying, or cyber-attacks. Many clinical researchers have done extensive study on this topic. The most recent studies on this topic are summarized, and an overarching framework is provided. When it comes to the methods and datasets that make up the data collection, the feature presentation and algorithm selection layers provide an overview of the various types of algorithm selections available. The categorization and evaluation of diseases and disorders has been one of the major advantages of machine learning in medical. Because it was harder to predict, it rendered it more controllable. It might range from difficult-to-find cancers in the early stages to certain other illnesses spread through the bloodstream. In healthcare, we may pick methods in machine learning depending on reliable outcomes. To do so, we must run the findings through each method. The major issue arises during information training and validation. Because the dataset is so large, eliminating mistakes might be difficult. The providers, other characteristics, various algorithms, data labelling techniques, and assessment criteria are all presented and contrasted in depth. Detecting anomalous users in medical social networks, on the other hand, is a work in progress. The result evaluation layer provides an explanation of how to evaluate and mark up the results of the various algorithm selection layers. Finally, it looks forward to more study in this area., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 T. Veeramakali et al.)
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- 2022
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13. Proteomic Profiling and Pathway Analysis of Acid Stress-Induced Vasorelaxation of Mesenteric Arteries In Vitro.
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Mohanty I, Banerjee S, Mahanty A, Mohanty S, Nayak NR, Parija SC, and Mohanty BP
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- Actins metabolism, Adenosine Triphosphate metabolism, Animals, Chromatography, Liquid, Desmin metabolism, Mesenteric Arteries metabolism, Nitric Oxide Synthase, Proteomics, Tandem Mass Spectrometry, Acidosis metabolism, Vasodilation
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Although metabolic acidosis is associated with numerous pathophysiological conditions and its vasorelaxation effects have been well described in different animal and culture models, the molecular mechanisms of acidosis-induced vasorelaxation are not fully understood. Mesenteric artery models have been used extensively to examine the vascular response to various pathophysiological conditions. Our previous studies and several other reports have suggested the vascular responses of goat mesenteric arteries and human arteries to various stimuli, including acidic stress, are highly similar. In this study, to further identify the signaling molecules responsible for altered vasoreactivity in response to acidic pH, we examined the proteomic profile of acid stress-induced vasorelaxation using a goat mesenteric artery model. The vascular proteomes under acidic pH were compared using 2D-GE with 7 cm IPG strips and mini gels, LC-MS/MS, and MALDI TOF MS. The unique proteins identified by mass spectroscopy were actin, transgelin, WD repeat-containing protein 1, desmin, tropomyosin, ATP synthase β, Hsp27, aldehyde dehydrogenase, pyruvate kinase, and vitamin K epoxide reductase complex subunit 1-like protein. Out of five protein spots identified as actin, three were upregulated > 2-fold. ATP synthase β was also upregulated (2.14-fold) under acid stress. Other actin-associated proteins upregulated were transgelin, desmin, and WD repeat-containing protein 1. Isometric contraction studies revealed that both receptor-mediated (histamine) and non-receptor-mediated (KCl) vasocontraction were attenuated, whereas acetylcholine-induced vasorelaxation was augmented under acidosis. Overall, the altered vasoreactivity under acidosis observed in the functional studies could possibly be attributed to the increase in expression of actin and ATP synthase β.
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- 2022
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14. Glutamate Uptake Is Not Impaired by Hypoxia in a Culture Model of Human Fetal Neural Stem Cell-Derived Astrocytes.
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Shrivastava V, Dey D, Singal CMS, Jaiswal P, Singh A, Sharma JB, Chattopadhyay P, Nayak NR, Palanichamy JK, Sinha S, Seth P, and Sen S
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- Cell Hypoxia, Cells, Cultured, Excitatory Amino Acid Transporter 1 genetics, Excitatory Amino Acid Transporter 1 metabolism, Humans, Astrocytes metabolism, Glutamic Acid metabolism, Neural Stem Cells metabolism
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Hypoxic ischemic injury to the fetal and neonatal brain is a leading cause of death and disability worldwide. Although animal and culture studies suggest that glutamate excitotoxicity is a primary contributor to neuronal death following hypoxia, the molecular mechanisms, and roles of various neural cells in the development of glutamate excitotoxicity in humans, is not fully understood. In this study, we developed a culture model of human fetal neural stem cell (FNSC)-derived astrocytes and examined their glutamate uptake in response to hypoxia. We isolated, established, and characterized cultures of FNSCs from aborted fetal brains and differentiated them into astrocytes, characterized by increased expression of the astrocyte markers glial fibrillary acidic protein (GFAP), excitatory amino acid transporter 1 (EAAT1) and EAAT2, and decreased expression of neural stem cell marker Nestin. Differentiated astrocytes were exposed to various oxygen concentrations mimicking normoxia (20% and 6%), moderate and severe hypoxia (2% and 0.2%, respectively). Interestingly, no change was observed in the expression of the glutamate transporter EAAT2 or glutamate uptake by astrocytes, even after exposure to severe hypoxia for 48 h. These results together suggest that human FNSC-derived astrocytes can maintain glutamate uptake after hypoxic injury and thus provide evidence for the possible neuroprotective role of astrocytes in hypoxic conditions.
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- 2022
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15. Feature extraction with capsule network for the COVID-19 disease prediction though X-ray images.
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Darji PA, Nayak NR, Ganavdiya S, Batra N, and Guhathakurta R
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Past couple of years, the world is going through one of the biggest pandemic named COVID-19. In the mid of year 2019, it is a very difficult process to predict the COVID-19 just by viewing the images. Later on AI based technology has done a significant role in the prediction of COVID-19 through biomedical images such as CT scan, X ray etc. This study also implemented the deep learning model for the prediction of COVID-19 through X-ray images. The implemented model is termed as XR-CAPS which consist of two models such as U-Net model and the capsule network. The U Net model is used for performing the segmentation of the images and the capsule networks are applied for performing the feature extraction. The XR-CAPS model is applied on the X-ray images for the prediction of COVID-19 and the evaluation of the model is done by three parameters that are accuracy, sensitivity and specificity. The model is compared with other existing models like ResNet50, DenseNet121 and DenseCapsNet, this has achieved an accuracy of 93.2%, sensitivity of 94% and specificity of 97.1% which is better than other states of the art algorithms., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the First International Conference on Design and Materials (ICDM)-2021.)
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- 2022
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16. VEGF Maintains Maternal Vascular Space Homeostasis in the Mouse Placenta through Modulation of Trophoblast Giant Cell Functions.
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Fan X, Muruganandan S, Shallie PD, Dhal S, Petitt M, and Nayak NR
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- Animals, Cell Differentiation, Endometrium metabolism, Female, Giant Cells, Homeostasis, Male, Mice, Inbred Strains, Pregnancy, Trophoblasts cytology, Vascular Endothelial Growth Factor Receptor-1 genetics, Vascular Endothelial Growth Factor Receptor-1 metabolism, Mice, Placenta blood supply, Placenta cytology, Trophoblasts physiology, Vascular Endothelial Growth Factor A metabolism
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Vascular endothelial growth factor (VEGF) is an angiogenic growth factor that acts primarily on endothelial cells, but numerous studies suggest that VEGF also acts on non-endothelial cells, including trophoblast cells. Inhibition of VEGF signaling by excess production of the endogenous soluble VEGF receptor sFlt1 in trophoblast cells has been implicated in several pregnancy complications. Our previous studies and other reports have shown that VEGF directly regulates placental vascular development and functions and that excess VEGF production adversely affects placental vascular development. Trophoblast giant cells (TGCs) line the maternal side of the placental vasculature in mice and function like endothelial cells. In this study, we specifically examined the effect of excess VEGF signaling on TGC development associated with defective placental vascular development using two mouse models an endometrial VEGF overexpression model and a placenta-specific sFlt1 knockdown model. Placentas of endometrial VEGF-overexpressing dams at embryonic days (E) 11.5 and 14.5 showed dramatic enlargement of the venous maternal spaces in junctional zones. The size and number of the parietal TGCs that line these venous spaces in the placenta were also significantly increased. Although junctional zone venous blood spaces from control and VEGF-overexpressing dams were not markedly different in size at E17.5, the number and size of P-TGCs were both significantly increased in the placentas from VEGF-overexpressing dams. In sFlt1 knockdown placentas, however, there was a significant increase in the size of the sinusoidal TGC-lined, alkaline phosphatase-positive maternal blood spaces in the labyrinth. These results suggest that VEGF signaling plays an important role in maintaining the homeostasis of the maternal vascular space in the mouse placenta through modulation of TGC development and differentiation, similar to the effect of VEGF on endothelial cells in other vascular beds.
- Published
- 2021
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17. Contribution of macrophages to fetomaternal immunological tolerance.
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Parasar P, Guru N, and Nayak NR
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- Animals, Female, Histocompatibility, Maternal-Fetal, Humans, Pregnancy, Th1-Th2 Balance, Decidua immunology, Immune Tolerance immunology, Macrophages immunology, Pregnancy Complications immunology
- Abstract
The semi-allogeneic fetus develops in a uniquely immune tolerant environment within the uterus. For successful pregnancy, both the innate and adaptive immune systems must favor acceptance of the fetal allograft. Macrophages are the second most abundant immune cells after natural killer (NK) cells in the decidua. In coordination with decidual NK cells and dendritic cells, macrophages aid in implantation, vascular remodeling, placental development, immune tolerance to placental cells, and maintenance of tissue homeostasis at the maternal-fetal interface. Decidual macrophages show the classical activated (M1) and alternatively activated (M2) phenotypes under the influence of the local milieu of growth factors and cytokines, and appropriate temporal regulation of the M1/M2 switch is vital for successful pregnancy. Disturbances in the mechanisms that control the M1/M2 balance and associated functions during pregnancy can trigger a spectrum of pregnancy complications ranging from preeclampsia and fetal growth restriction to preterm delivery. This review addresses various mechanisms of tolerance, focusing on the basic biology of macrophages, their plasticity and polarization, and their protective roles at the immune-privileged maternal-fetal interface, including direct and indirect roles in promoting fetomaternal immune tolerance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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18. Pathogenesis of Preeclampsia and Therapeutic Approaches Targeting the Placenta.
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Jena MK, Sharma NR, Petitt M, Maulik D, and Nayak NR
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- Female, Humans, Placenta metabolism, Pre-Eclampsia metabolism, Pregnancy, Vascular Endothelial Growth Factor Receptor-1 metabolism, Placenta drug effects, Placenta pathology, Pre-Eclampsia drug therapy, Pre-Eclampsia pathology
- Abstract
Preeclampsia (PE) is a serious pregnancy complication, affecting about 5-7% of pregnancies worldwide and is characterized by hypertension and damage to multiple maternal organs, primarily the liver and kidneys. PE usually begins after 20 weeks' gestation and, if left untreated, can lead to serious complications and lifelong disabilities-even death-in both the mother and the infant. As delivery is the only cure for the disease, treatment is primarily focused on the management of blood pressure and other clinical symptoms. The pathogenesis of PE is still not clear. Abnormal spiral artery remodeling, placental ischemia and a resulting increase in the circulating levels of vascular endothelial growth factor receptor-1 (VEGFR-1), also called soluble fms-like tyrosine kinase-1 (sFlt-1), are believed to be among the primary pathologies associated with PE. sFlt-1 is produced mainly in the placenta during pregnancy and acts as a decoy receptor, binding to free VEGF (VEGF-A) and placental growth factor (PlGF), resulting in the decreased bioavailability of each to target cells. Despite the pathogenic effects of increased sFlt-1 on the maternal vasculature, recent studies from our laboratory and others have strongly indicated that the increase in sFlt-1 in PE may fulfill critical protective functions in preeclamptic pregnancies. Thus, further studies on the roles of sFlt-1 in normal and preeclamptic pregnancies are warranted for the development of therapeutic strategies targeting VEGF signaling for the treatment of PE. Another impediment to the treatment of PE is the lack of suitable methods for delivery of cargo to placental cells, as PE is believed to be of placental origin and most available therapies for PE adversely impact both the mother and the fetus. The present review discusses the pathogenesis of PE, the complex role of sFlt-1 in maternal disease and fetal protection, and the recently developed placenta-targeted drug delivery system for the potential treatment of PE with candidate therapeutic agents.
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- 2020
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19. Development of A 3D Tissue Slice Culture Model for the Study of Human Endometrial Repair and Regeneration.
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Muruganandan S, Fan X, Dhal S, and Nayak NR
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- Cell Differentiation, Cell Survival, Endometrium cytology, Endometrium ultrastructure, Equipment Design, Female, Humans, Regeneration, Tissue Culture Techniques instrumentation, Endometrium physiology, Tissue Culture Techniques methods
- Abstract
The human endometrium undergoes sequential phases of shedding of the upper functionalis zone during menstruation, followed by regeneration of the functionalis zone from the remaining basalis zone cells, and secretory differentiation under the influence of the ovarian steroid hormones estradiol (E2) and progesterone (P4). This massive tissue regeneration after menstruation is believed to arise from endometrial stromal and epithelial stem cells residing in the basal layer of the endometrium. Although many endometrial pathologies are thought to be associated with defects in these stem cells, studies on their identification and regulation are limited, primarily due to lack of easily accessible animal models, as these processes are unique to primates. Here we describe a robust new method to study endometrial regeneration and differentiation processes using human endometrial tissue slice cultures incorporating an air-liquid interface into a 3D matrix scaffold of type I collagen gel, allowing sustained tissue viability over three weeks. The 3D collagen gel-embedded endometrial tissue slices in a double-dish culture system responded to ovarian steroid hormones, mimicking the endometrial changes that occur in vivo during the menstrual cycle. These changes included the E2-induced upregulation of Ki-67, estrogen receptor (ER), and progesterone receptor (PR) in all endometrial compartments and were markedly suppressed by both P4 and E2 plus P4 treatments. There were also distinct changes in endometrial morphology after E2 and P4 treatments, including subnuclear vacuolation and luminal secretions in glands as well as decidualization of stromal cells, typical characteristics of a progestational endometrium in vivo . This long-term slice culture method provides a unique in vivo-like microenvironment for the study of human endometrial functions and remodeling during early pregnancy and experiments on stem cell populations involved in endometrial regeneration and remodeling. Furthermore, this model has the potential to enable studies on several endometrial diseases, including endometrial cancers and pregnancy complications associated with defects in endometrial remodeling., Competing Interests: The authors declare no conflict of interest.
- Published
- 2020
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20. Role of Macrophages in Pregnancy and Related Complications.
- Author
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Jena MK, Nayak N, Chen K, and Nayak NR
- Subjects
- Animals, Embryo Implantation immunology, Female, Humans, Immune Tolerance, Macrophages immunology, Macrophages pathology, Pregnancy Complications pathology, Vascular Endothelial Growth Factors metabolism, Decidua immunology, Macrophages physiology, Pregnancy immunology, Pregnancy Complications immunology
- Abstract
Macrophages (MФs) are the leukocytes produced from differentiation of monocytes and are located in almost all tissues of human body. They are involved in various processes, such as phagocytosis, innate and adaptive immunity, proinflammatory (M1) and anti-inflammatory (M2) activity, depending on the tissue microenvironment. They play a crucial role in pregnancy, and their dysfunction or alteration of polarity is involved in pregnancy disorders, like preeclampsia, recurrent spontaneous abortion, infertility, intrauterine growth restriction, and preterm labor. About 50-60% of decidual leukocytes are natural killer (NK) cells followed by MФs (the second largest population). MФs are actively involved in trophoblast invasion, tissue and vascular remodeling during early pregnancy, besides their role as major antigen-presenting cells in the decidua. These cells have different phenotypes and polarities in different stages of pregnancy. They have also been observed to enhance tumor growth by their anti-inflammatory activity (M2 type) and prevent immunogenic rejection. Targeted alteration of polarity (M1-M2 or vice versa) could be a major focus in the future treatment of pregnancy complications. This review is focused on the role of MФs in pregnancy, their involvement in pregnancy disorders, and decidual MФs as possible therapeutic targets for the treatment of pregnancy complications.
- Published
- 2019
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21. Mumps outbreak investigation in Jaisalmer, Rajasthan, India, June-September 2016.
- Author
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Moghe CS, Goel P, Singh J, Nayak NR, Dhuria M, Jain R, Yadav R, Saroha E, Sodha SV, Aggarwal CS, and Venkatesh S
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Female, Humans, Immunoglobulin M blood, Incidence, India epidemiology, Infant, Male, Mumps blood, Mumps virus immunology, Vaccination statistics & numerical data, Young Adult, Antibodies, Viral blood, Disease Outbreaks, Mumps epidemiology
- Abstract
Mumps, a vaccine-preventable disease, cause inflammation of salivary glands and may cause severe complications, such as encephalitis, meningitis, deafness, and orchitis/oophoritis. In India, mumps vaccine is not included in the universal immunization program and during 2009 to 2014, 72 outbreaks with greater than 1500 cases were reported. In August 2016, a suspected mumps outbreak was reported in Jaisalmer block, Rajasthan. We investigated to confirm the etiology, describe the epidemiology, and recommend prevention and control measures. We defined a case as swelling in the parotid region in a Jaisalmer block resident between 23 June 2016 and 10 September 2016. We searched for cases in health facilities and house-to-house in affected villages and hamlets. We tested blood samples of cases for mumps immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA). We found 162 cases (60% males) with a median age of 9.4 years (range: 7 month-38 years) and 65 (40%) were females. Symptoms included fever (70%) and bilateral swelling in neck (65%). None of them were vaccinated against mumps. Most (84%) cases were school-going children (3-16 years old). The overall attack rate was 2%. Village A, with two hamlets, had the highest attack rate (hamlet 1 = 13% and hamlet 2 = 12%). School A of village A, hamlet 1, which accommodated 200 children in two classrooms, had an attack rate of 55%. Of 18 blood samples from cases, 11 tested positive for mumps IgM ELISA. This was a confirmed mumps outbreak in Jaisalmer block that disproportionately affected school-going children. We recommended continued surveillance, 5-day absence from school, and vaccination., (© 2018 Wiley Periodicals, Inc.)
- Published
- 2019
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22. Quality of Life in Patients Undergoing Spine Surgery: Systematic Review and Meta-Analysis.
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Nayak NR, Stephen JH, Piazza MA, Obayemi AA, Stein SC, and Malhotra NR
- Abstract
Study Design: Meta-analysis., Objective: Despite the increasing importance of tracking clinical outcomes using valid patient-reported outcome measures, most providers do not routinely obtain baseline preoperative health-related quality of life (HRQoL) data in patients undergoing spine surgery, precluding objective outcomes analysis in individual practices. We conducted a meta-analysis of pre- and postoperative HRQoL data obtained from the most commonly published instruments to use as reference values., Methods: We searched PubMed, EMBASE, and an institutional registry for studies reporting EQ-5D, SF-6D, and Short Form-36 Physical Component Summary scores in patients undergoing surgery for degenerative cervical and lumbar spinal conditions published between 2000 and 2014. Observational data was pooled meta-analytically using an inverse variance-weighted, random-effects model, and statistical comparisons were performed., Results: Ninety-nine articles were included in the final analysis. Baseline HRQoL scores varied by diagnosis for each of the 3 instruments. On average, postoperative HRQoL scores significantly improved following surgical intervention for each diagnosis using each instrument. There were statistically significant differences in baseline utility values between the EQ-5D and SF-6D instruments for all lumbar diagnoses., Conclusions: The pooled HRQoL values presented in this study may be used by practitioners who would otherwise be precluded from quantifying their surgical outcomes due to a lack of baseline data. The results highlight differences in HRQoL between different degenerative spinal diagnoses, as well as the discrepancy between 2 common utility-based instruments. These findings emphasize the need to be cognizant of the specific instruments used when comparing the results of outcome studies., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2019
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23. Pravastatin improves fetal survival in mice with a partial deficiency of heme oxygenase-1.
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Tsur A, Kalish F, Burgess J, Nayak NR, Zhao H, Casey KM, Druzin ML, Wong RJ, and Stevenson DK
- Subjects
- Animals, Drug Evaluation, Preclinical, Female, Hydroxymethylglutaryl-CoA Reductase Inhibitors pharmacology, Liver drug effects, Liver enzymology, Mice, Pravastatin pharmacology, Pregnancy, Random Allocation, Heme Oxygenase-1 metabolism, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Membrane Proteins metabolism, Placentation drug effects, Pravastatin therapeutic use, Pre-Eclampsia prevention & control
- Abstract
Introduction: Statins induce heme oxygenase-1 (HO-1) expression in vitro and in vivo. Low HO-1 expression is associated with pregnancy complications, e.g. preeclampsia and recurrent miscarriages. Here, we investigated the effects of pravastatin on HO-1 expression, placental development, and fetal survival in mice with a partial HO-1 deficiency., Methods: At E14.5, untreated pregnant wild-type (WT, n=13-18), untreated HO-1
+/- (Het, n=6-9), and Het mice treated with pravastatin (Het+Pravastatin, n=12-14) were sacrificed. Numbers of viable fetuses/resorbed concepti were recorded. Maternal livers and placentas were harvested for HO activity. Hematoxylin and eosin (H&E) and CD31 immunohistochemical staining were performed on whole placentas., Results: Compared with WT, HO activity in Het livers (65±18%, P<0.001) and placentas (74±7%, P<0.001) were significantly decreased. Number of viable fetuses per dam was significantly lower in Untreated Het dams (6.0±2.2) compared with WT (9.1±1.4, P<0.01), accompanied by a higher relative risk (RR) for concepti resorption (17.1, 95% CI 4.0-73.2). In Hets treated with pravastatin, maternal liver and placental HO activity increased, approaching levels of WT controls (to 83±7% and 87±14%, respectively). The number of viable fetuses per dam increased to 7.7±2.5 with a decreased RR for concepti resorption (2.7, 95% CI 1.2-5.9). In some surviving Untreated Het placentas, there were focal losses of cellular architecture and changes suggestive of reduced blood flow in the labyrinth. These findings were absent in Het+Pravastatin placentas., Discussion: Pravastatin induces maternal liver and placental HO activity, may affect placental function and improve fetal survival in the context of a partial deficiency of HO-1., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2019
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24. Comprehensive Evaluation of the Effectiveness and Safety of Placenta-Targeted Drug Delivery Using Three Complementary Methods.
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Zhang B, Chen Z, Han J, Li M, Nayak NR, and Fan X
- Subjects
- Chondroitin Sulfates metabolism, Drug Carriers chemistry, Female, Humans, Methotrexate metabolism, Nanoparticles chemistry, Peptides chemistry, Peptides metabolism, Pregnancy, Drug Delivery Systems adverse effects, Drug Delivery Systems methods, Placenta metabolism, Safety
- Abstract
No effective treatments currently exist for placenta-associated pregnancy complications, and developing strategies for the targeted delivery of drugs to the placenta while minimizing fetal and maternal side effects remains challenging. Targeted nanoparticle carriers provide new opportunities to treat placental disorders. We recently demonstrated that a synthetic placental chondroitin sulfate A binding peptide (plCSA-BP) could be used to guide nanoparticles to deliver drugs to the placenta. In this protocol, we describe in detail a system for assessing the efficiency of drug delivery to the placenta by plCSA-BP that employs three separate methods used in combination: in vivo imaging, high-frequency ultrasound (HFUS), and high-performance liquid chromatography (HPLC). Using in vivo imaging, plCSA-BP-guided nanoparticles were visualized in the placentas of live animals, while HFUS and HPLC demonstrated that plCSA-BP-conjugated nanoparticles efficiently and specifically delivered methotrexate to the placenta. Thus, a combination of these methods can be used as an effective tool for the targeted delivery of drugs to the placenta and development of new treatment strategies for several pregnancy complications.
- Published
- 2018
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25. A Retrospective Propensity Score-Matched Early Thromboembolic Event Analysis of Prothrombin Complex Concentrate vs Fresh Frozen Plasma for Warfarin Reversal Prior to Emergency Neurosurgical Procedures.
- Author
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Agarwal P, Abdullah KG, Ramayya AG, Nayak NR, and Lucas TH
- Subjects
- Aged, Anticoagulants therapeutic use, Female, Humans, Incidence, Male, Middle Aged, Neurosurgical Procedures methods, Propensity Score, Retrospective Studies, Trauma Centers, Blood Coagulation Factors therapeutic use, Intracranial Hemorrhages surgery, Plasma, Thromboembolism epidemiology, Warfarin antagonists & inhibitors
- Abstract
Background: Reversal of therapeutic anticoagulation prior to emergency neurosurgical procedures is required in the setting of intracranial hemorrhage. Multifactor prothrombin complex concentrate (PCC) promises rapid efficacy but may increase the probability of thrombotic complications compared to fresh frozen plasma (FFP)., Objective: To compare the rate of thrombotic complications in patients treated with PCC or FFP to reverse therapeutic anticoagulation prior to emergency neurosurgical procedures in the setting of intracranial hemorrhage at a level I trauma center., Methods: Sixty-three consecutive patients on warfarin therapy presenting with intracranial hemorrhage who received anticoagulation reversal prior to emergency neurosurgical procedures were retrospectively identified between 2007 and 2016. They were divided into 2 cohorts based on reversal agent, either PCC (n = 28) or FFP (n = 35). The thrombotic complications rates within 72 h of reversal were compared using the χ2 test. A multivariate propensity score matching analysis was used to limit the threat to interval validity from selection bias arising from differences in demographics, laboratory values, history, and clinical status., Results: Thrombotic complications were uncommon in this neurosurgical population, occurring in 1.59% (1/63) of treated patients. There was no significant difference in the thrombotic complication rate between groups, 3.57% (1/28; PCC group) vs 0% (0/35; FFP group). Propensity score matching analysis validated this finding after controlling for any selection bias., Conclusion: In this limited sample, thrombotic complication rates were similar between use of PCC and FFP for anticoagulation reversal in the management of intracranial hemorrhage prior to emergency neurosurgical procedures.
- Published
- 2018
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26. KELCH F-BOX protein positively influences Arabidopsis seed germination by targeting PHYTOCHROME-INTERACTING FACTOR1.
- Author
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Majee M, Kumar S, Kathare PK, Wu S, Gingerich D, Nayak NR, Salaita L, Dinkins R, Martin K, Goodin M, Dirk LMA, Lloyd TD, Zhu L, Chappell J, Hunt AG, Vierstra R, Huq E, and Downie AB
- Subjects
- Arabidopsis genetics, Arabidopsis Proteins genetics, Basic Helix-Loop-Helix Transcription Factors genetics, Kelch Repeat, Seeds genetics, Arabidopsis metabolism, Arabidopsis Proteins metabolism, Basic Helix-Loop-Helix Transcription Factors metabolism, Germination physiology, Seeds metabolism
- Abstract
Seeds employ sensory systems that assess various environmental cues over time to maximize the successful transition from embryo to seedling. Here we show that the Arabidopsis F-BOX protein COLD TEMPERATURE-GERMINATING (CTG)-10, identified by activation tagging, is a positive regulator of this process. When overexpressed (OE), CTG10 hastens aspects of seed germination. CTG10 is expressed predominantly in the hypocotyl, and the protein is localized to the nucleus. CTG10 interacts with PHYTOCHROME-INTERACTING FACTOR 1 (PIF1) and helps regulate its abundance in planta CTG10-OE accelerates the loss of PIF1 in light, increasing germination efficiency, while PIF1-OE lines fail to complete germination in darkness, which is reversed by concurrent CTG10 - OE Double-mutant ( pif1 ctg10 ) lines demonstrated that PIF1 is epistatic to CTG10. Both CTG10 and PIF1 amounts decline during seed germination in the light but reaccumulate in the dark. PIF1 in turn down-regulates CTG10 transcription, suggesting a feedback loop of CTG10/PIF1 control. The genetic, physiological, and biochemical evidence, when taken together, leads us to propose that PIF1 and CTG10 coexist, and even accumulate, in the nucleus in darkness, but that, following illumination, CTG10 assists in reducing PIF1 amounts, thus promoting the completion of seed germination and subsequent seedling development., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)
- Published
- 2018
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27. Placenta-specific drug delivery by trophoblast-targeted nanoparticles in mice.
- Author
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Zhang B, Tan L, Yu Y, Wang B, Chen Z, Han J, Li M, Chen J, Xiao T, Ambati BK, Cai L, Yang Q, Nayak NR, Zhang J, and Fan X
- Subjects
- Animals, Antigens, Protozoan metabolism, Enzyme Inhibitors administration & dosage, Enzyme Inhibitors pharmacokinetics, Female, Humans, Methotrexate administration & dosage, Methotrexate pharmacokinetics, Mice, Nanoparticles adverse effects, Pregnancy, Nanoparticles metabolism, Trophoblasts metabolism
- Abstract
Rationale: The availability of therapeutics to treat pregnancy complications is severely lacking, mainly due to the risk of harm to the fetus. In placental malaria, Plasmodium falciparum- infected erythrocytes (IEs) accumulate in the placenta by adhering to chondroitin sulfate A (CSA) on the surfaces of trophoblasts. Based on this principle, we have developed a method for targeted delivery of payloads to the placenta using a synthetic placental CSA-binding peptide (plCSA-BP) derived from VAR2CSA, a CSA-binding protein expressed on IEs. Methods: A biotinylated plCSA-BP was used to examine the specificity of plCSA-BP binding to mouse and human placental tissue in tissue sections in vitro . Different nanoparticles, including plCSA-BP-conjugated nanoparticles loaded with indocyanine green (plCSA-INPs) or methotrexate (plCSA-MNPs), were administered intravenously to pregnant mice to test their efficiency at drug delivery to the placenta in vivo . The tissue distribution and localization of the plCSA-INPs were monitored in live animals using an IVIS imaging system. The effect of plCSA-MNPs on fetal and placental development and pregnancy outcome were examined using a small-animal high-frequency ultrasound (HFUS) imaging system, and the concentrations of methotrexate in fetal and placental tissues were measured using high-performance liquid chromatography (HPLC). Results: plCSA-BP binds specifically to trophoblasts and not to other cell types in the placenta or to CSA-expressing cells in other tissues. Moreover, we found that intravenously administered plCSA-INPs accumulate in the mouse placenta, and ex vivo analysis of the fetuses and placentas confirmed placenta-specific delivery of these nanoparticles. We also demonstrate successful delivery of methotrexate specifically to placental cells by plCSA-BP-conjugated nanoparticles, resulting in dramatic impairment of placental and fetal development. Importantly, plCSA-MNPs treatment had no apparent adverse effects on maternal tissues. Conclusion: These results demonstrate that plCSA-BP-guided nanoparticles could be used for the targeted delivery of payloads to the placenta and serve as a novel placenta-specific drug delivery option., Competing Interests: Competing Interests: X.F., B.Z., and J.Z. are inventors on patent application PCT/CN2017/108646 submitted by SIAT that covers a placenta-specific drug delivery method and its application. All other authors declare that they have no competing interests.
- Published
- 2018
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28. Surgical Approaches for the Treatment of Multilevel Cervical Ossification of the Posterior Longitudinal Ligament: Results of a Decision Analysis.
- Author
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Nayak NR, Piazza M, Milby A, Thawani JP, Smith LJ, Stein SC, and Malhotra NR
- Subjects
- Decision Support Techniques, Humans, Middle Aged, Quality of Life, Treatment Outcome, Cervical Vertebrae surgery, Decompression, Surgical methods, Laminectomy methods, Ossification of Posterior Longitudinal Ligament surgery, Spinal Fusion methods
- Abstract
Background: Ossification of the posterior longitudinal ligament (OPLL) often leads to cervical myelopathy. Although multiple procedures have been shown to be effective in the treatment of OPLL, outcomes are less predictable than in degenerative cervical myelopathy, and surgery is associated with high rates of complications and reoperation, which affect quality of life. In this study, we performed a decision analysis using postoperative complication data and health-related quality of life (HRQoL) utility scores to assess the average expected health utility and 5-year quality-adjusted life years (QALYs) associated with the most common surgical approaches for multilevel cervical OPLL., Methods: We searched Medline, EMBASE, and the Cochrane Library for relevant articles published between 1990 and October 2017. Meta-analytically pooled complication data and HRQoL utility scores associated with each complication were evaluated in a long-term model., Results: The overall incidence of perioperative complications ranged from 6.2% for laminectomy alone to 11.0% for anterior decompression and fusion. Revision surgery for hardware/fusion failure or progression was highest for laminectomy alone (3.0%) and lowest for laminectomy and fusion (1.6%). Laminoplasty resulted in the highest 5-year QALYs gained, compared with laminectomy and anterior approaches (P < 0.001). There was no significant difference in QALY gained between laminectomy-fusion and laminoplasty., Conclusion: The results suggest that owing to the higher rates of complications associated with anterior cervical approaches, laminoplasty may result in improved long-term outcomes from an HRQoL standpoint. These findings may guide surgeons in cases where either procedure is a reasonable option., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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29. VEGF may contribute to macrophage recruitment and M2 polarization in the decidua.
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Wheeler KC, Jena MK, Pradhan BS, Nayak N, Das S, Hsu CD, Wheeler DS, Chen K, and Nayak NR
- Subjects
- Adult, Cell Line, Female, Humans, Real-Time Polymerase Chain Reaction, Cell Polarity, Decidua cytology, Macrophages cytology, Vascular Endothelial Growth Factor A physiology
- Abstract
It is increasingly evident that cytokines and growth factors produced in the decidua play a pivotal role in the regulation of the local immune microenvironment and the establishment of pregnancy. One of the major growth factors produced in the decidua is vascular endothelial growth factor (VEGF), which acts not only on endothelial cells, but also on multiple other cell types, including macrophages. We sought to determine whether decidua-derived VEGF affects macrophage recruitment and polarization using human endometrial/decidual tissue samples, primary human endometrial stromal cells (ESCs), and the human monocyte cell line THP1. In situ hybridization was used for assessment of local VEGF expression and immunohistochemistry was used for identification and localization of CD68-positive endometrial macrophages. Macrophage migration in culture was assessed using a transwell migration assay, and the various M1/M2 phenotypic markers and VEGF expression were assessed using quantitative real-time PCR (qRT-PCR). We found dramatic increases in both VEGF levels and macrophage numbers in the decidua during early pregnancy compared to the secretory phase endometrium (non-pregnant), with a significant increase in M2 macrophage markers, suggesting that M2 is the predominant macrophage phenotype in the decidua. However, decidual samples from preeclamptic pregnancies showed a significant shift in macrophage phenotype markers, with upregulation of M1 and downregulation of M2 markers. In THP1 cultures, VEGF treatment significantly enhanced macrophage migration and induced M1 macrophages to shift to an M2 phenotype. Moreover, treatment with conditioned media from decidualized ESCs induced changes in macrophage migration and polarization similar to that of VEGF treatment. These effects were abrogated by the addition of a potent VEGF inhibitor. Together these results suggest that decidual VEGF plays a significant role in macrophage recruitment and M2 polarization, and that inhibition of VEGF signaling may contribute to the shift in macrophage polarity observed in different pregnancy disorders, including preeclampsia.
- Published
- 2018
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30. Suitable reference gene for quantitative real-time PCR analysis of gene expression in gonadal tissues of minnow Puntius sophore under high-temperature stress.
- Author
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Mahanty A, Purohit GK, Mohanty S, Nayak NR, and Mohanty BP
- Subjects
- Animals, Cyprinidae physiology, Female, Male, Reference Standards, Reproduction genetics, Cyprinidae genetics, Gene Expression Profiling standards, Heat-Shock Response genetics, Ovary metabolism, Real-Time Polymerase Chain Reaction standards, Testis metabolism
- Abstract
Background: High ambient temperature is known to affect fish gonadal development and physiology in a variety of ways depending on the severity and duration of exposure; however, the underlying molecular mechanisms are poorly understood. Gonadal gene expression influence the gonadal development, physiology and the quality of egg/sperm produced in teleosts and the mechanistic understanding of spatio-temporal changes in the gonadal gene expression could be instrumental in controlling the fate of egg/sperm and the quality of seed produced. Real time-quantititative polymerase chain reaction (RT-qCR), is a high throughput, sensitive and reproducible methodology used for understanding gene expression patterns by measuring the relative abundance of mRNA transcripts. However, its accuracy relies upon a suitable reference gene whose expression levels remain stable across various experimental conditions. In the present study, we evaluated the suitability of ten potential reference genes to be used as internal controls in RT-qPCR analysis in gonadal tissues (ovary and testis) of minnow Puntius sophore exposed to high temperature stress for different time periods (7 days, 60 days). Expression analysis of ten different constitutively expressed genes viz. 18S ribosomal RNA (18S rRNA), beta actin (βactin), β-2 microglobulin (b2mg), eukaryotic elongation factor-1 (eef1), glyceraldehyde-3phosphate dehydrogenase (gapdh), glucose-6-phosphate dehydrogenase (g6pd), ribosomal binding protein L13 (rpl13), tubulin (tub), tata box binding protein (tbp), ubiquitin (ubi) was carried out by using RT-qPCR and the stability in their expressions were evaluated by using four different algorithms; namely, delta Ct, BestKeeper, geNorm and NormFinder., Results: In ovary, eef1 was found to be the most suitable reference gene in all the algorithms used. In testis, b2mg was found to be the most suitable reference gene in delta Ct, BestKeeper, NormFinder analysis while tbp and eef1 were found to be the most suitable reference genes in geNorm analysis., Conclusions: In conclusion, eef1 and b2mg were found to be the most suitable reference genes in ovary and testis, respectively, of Puntius sophore exposed to high temperature stress, and could be used as internal controls for gene expression analysis in gonadal tissues of Puntius sophore.
- Published
- 2017
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31. Surgical Approaches for the Treatment of Thoracic Disk Herniation: Results of a Decision Analysis.
- Author
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Nayak NR, Bauman JA, Stein SC, Thawani JP, and Malhotra NR
- Subjects
- Humans, Postoperative Complications etiology, Quality of Life, Reoperation, Treatment Outcome, Decision Support Techniques, Intervertebral Disc Displacement surgery, Thoracic Vertebrae surgery
- Abstract
Study Design: A decision analysis., Objective: To perform a decision analysis utilizing postoperative complication data, in conjunction with health-related quality of life (HRQoL) utility scores, to rank order the average health utility associated with various surgical approaches used to treat symptomatic thoracic disk herniation (TDH)., Summary of Background Data: Symptomatic TDH is an uncommon entity accounting for <1% of all symptomatic herniated disks. A variety of surgical approaches have been developed for its treatment, which may be classified into 4 major categories: open anterolateral transthoracic, minimally invasive anterolateral thoracoscopic, posterior, and lateral. These treatments have varying risk/benefit profiles, but there is still no set algorithm for choosing an approach in cases with multiple surgical options., Methods: We searched Medline, EMBASE, and the Cochrane Library for relevant articles on surgical approaches for TDHs published between 1990 and August 2014. Pooled complication data and HRQoL utility scores associated with each complication were evaluated using standard meta-analytic techniques to determine which surgical approach resulted in the highest average HRQoL., Results: Posterior surgical approaches resulted in the highest average HRQoL, followed by thoracoscopic, lateral, and finally open anterolateral transthoracic procedures. The higher average HRQoL associated with posterior approaches over all others was highly significant (P<0.001); conversely, the open anterolateral approach resulted in a lower average postoperative utility compared with all other approaches (P<0.001)., Conclusions: The results of this decision analysis favor posterior over lateral approaches, and thoracoscopic over open anterolateral approaches for the treatment of symptomatic TDHs, which may guide surgeons in cases where multiple surgical options are feasible. Future studies, such as randomized clinical trials, are necessary to ascertain whether novel surgical strategies have risk/benefit profiles that ultimately supersede those of traditional approaches, and whether enough cases are encountered by the average surgeon to justify their adoption.
- Published
- 2017
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32. Evaluation of efficient glucose release using sodium hydroxide and phosphoric acid as pretreating agents from the biomass of Sesbania grandiflora (L.) Pers.: A fast growing tree legume.
- Author
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Mund NK, Dash D, Barik CR, Goud VV, Sahoo L, Mishra P, and Nayak NR
- Subjects
- Cellulase, Cellulose chemistry, Fabaceae, Glucose, Hydrolysis, Lignin chemistry, Phosphoric Acids, Sesbania, Spectroscopy, Fourier Transform Infrared, Biomass, Sodium Hydroxide chemistry
- Abstract
Sesbania grandiflora (L.) Pers. is one of the fast growing tree legumes having the efficiency to produce around 50tha
-1 above ground dry matters in a year. In this study, biomass of 2years old S. grandiflora was selected for the chemical composition, pretreatments and enzymatic hydrolysis studies. The stem biomass with a wood density of 3.89±0.01gmcm-3 contains about 38% cellulose, 12% hemicellulose and 28% lignin. Enzymatic hydrolysis of pretreated biomass revealed that phosphoric acid (H3 PO4 ) pretreated samples even at lower cellulase loadings [1 Filter Paper Units (FPU)], could efficiently convert about 86% glucose, while, even at higher cellulase loadings (60FPU) alkali pretreated biomass could convert only about 58% glucose. The effectiveness of phosphoric acid pretreatment was also supported by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR) analysis., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
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33. Long-term utility and complication profile of open craniotomy for biopsy in patients with idiopathic encephalitis.
- Author
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Abdullah KG, Li Y, Agarwal P, Nayak NR, Thawani JP, Balu R, and Lucas TH
- Subjects
- Adult, Aged, Aged, 80 and over, Biopsy adverse effects, Biopsy methods, Brain surgery, Craniotomy methods, Encephalitis pathology, Female, Humans, Male, Middle Aged, Brain pathology, Craniotomy adverse effects, Encephalitis surgery, Postoperative Complications
- Abstract
Neurosurgeons are often asked to perform open biopsy for diagnosis of encephalitis after medical investigations are non-diagnostic. These patients may be critically ill with multiple comorbidities. Patients and their families often request data regarding the success rates and complication profile of biopsy, but minimal literature exists in this area. Retrospective chart review of all patients undergoing open brain biopsy (burr hole or craniotomy) for encephalitis refractory to medical diagnosis between January 2009 and December 2013 was undertaken. Pathology records and outpatient follow-up were reviewed to determine most recent clinical status of each patient. A total of 59 patients were included with mean follow up of 20months. The average age at biopsy was 55years. The most common unconfirmed diagnoses leading to biopsy were vasculitis (44%), neoplasm (27%), infection (12%), autoimmune (12%), amyloidosis (5%). Tissue pathology was diagnostic in 42% of all cases. Overall, biopsy confirmed the preoperative diagnosis in 46% of cases and refuted the preoperative leading diagnosis in 25% of cases. At last follow-up, the tissue pathology resulted in a medical treatment change in 25% of cases. There was a 14% major neurological complication rate (postoperative stroke, hemorrhage, or neurological deficit) and 9% cardiopulmonary complication rate (delayed extubation and re-intubation) attributable to surgical intervention. In this limited series, diagnostic utility of biopsy in patients with idiopathic encephalitis is less than 50% and the major complication rate is 23%. Patients and providers must be counseled accordingly and weigh the risks and benefits of open biopsy for encephalitis cautiously., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
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34. Synovial-type giant cell tumors of the axial spine.
- Author
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Nayak NR, Richard CE, Martinez-Lage M, Smith H, and Malhotra NR
- Subjects
- Aged, Diffusion Magnetic Resonance Imaging methods, Female, Giant Cell Tumors diagnosis, Humans, Male, Spinal Neoplasms diagnosis, Treatment Outcome, Giant Cell Tumors pathology, Giant Cell Tumors surgery, Spinal Neoplasms pathology, Spinal Neoplasms surgery, Spine surgery
- Published
- 2017
35. Interleukin-33-induced expression of PIBF1 by decidual B cells protects against preterm labor.
- Author
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Huang B, Faucette AN, Pawlitz MD, Pei B, Goyert JW, Zhou JZ, El-Hage NG, Deng J, Lin J, Yao F, Dewar RS 3rd, Jassal JS, Sandberg ML, Dai J, Cols M, Shen C, Polin LA, Nichols RA, Jones TB, Bluth MH, Puder KS, Gonik B, Nayak NR, Puscheck E, Wei WZ, Cerutti A, Colonna M, and Chen K
- Subjects
- Adult, Animals, B-Lymphocytes immunology, Blotting, Western, Decidua cytology, Decidua immunology, Disease Models, Animal, Enzyme-Linked Immunosorbent Assay, Female, Flow Cytometry, Fluorescent Antibody Technique, Humans, Immunohistochemistry, Interleukin-1 Receptor-Like 1 Protein immunology, Interleukin-1 Receptor-Like 1 Protein metabolism, Interleukin-33 immunology, Mice, Obstetric Labor, Premature immunology, Pregnancy, Pregnancy Proteins immunology, Young Adult, B-Lymphocytes metabolism, Decidua metabolism, Interleukin-33 metabolism, Obstetric Labor, Premature metabolism, Pregnancy Proteins metabolism
- Abstract
Preterm birth (PTB) is a leading cause of neonatal death worldwide. Intrauterine and systemic infection and inflammation cause 30-40% of spontaneous preterm labor (PTL), which precedes PTB. Although antibody production is a major immune defense mechanism against infection, and B cell dysfunction has been implicated in pregnancy complications associated with PTL, the functions of B cells in pregnancy are not well known. We found that choriodecidua of women undergoing spontaneous PTL harbored functionally altered B cell populations. B cell-deficient mice were markedly more susceptible than wild-type (WT) mice to PTL after inflammation, but B cells conferred interleukin (IL)-10-independent protection against PTL. B cell deficiency in mice resulted in a lower uterine level of active progesterone-induced blocking factor 1 (PIBF1), and therapeutic administration of PIBF1 mitigated PTL and uterine inflammation in B cell-deficient mice. B cells are a significant producer of PIBF1 in human choriodecidua and mouse uterus in late gestation. PIBF1 expression by B cells is induced by the mucosal alarmin IL-33 (ref. 9). Human PTL was associated with diminished expression of the α-chain of IL-33 receptor on choriodecidual B cells and a lower level of active PIBF1 in late gestation choriodecidua. These results define a vital regulatory cascade involving IL-33, decidual B cells and PIBF1 in safeguarding term pregnancy and suggest new therapeutic approaches based on IL-33 and PIBF1 to prevent human PTL.
- Published
- 2017
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36. Navigated odontoid screw placement using the O-arm: technical note and case series.
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Pisapia JM, Nayak NR, Salinas RD, Macyszyn L, Lee JY, Lucas TH, Malhotra NR, Isaac Chen H, and Schuster JM
- Subjects
- Accidental Falls, Adolescent, Adult, Aged, Aged, 80 and over, Female, Fluoroscopy instrumentation, Fluoroscopy methods, Follow-Up Studies, Fracture Fixation, Internal adverse effects, Fracture Fixation, Internal instrumentation, Humans, Imaging, Three-Dimensional instrumentation, Male, Middle Aged, Odontoid Process diagnostic imaging, Odontoid Process injuries, Prospective Studies, Retrospective Studies, Spinal Fractures diagnostic imaging, Spinal Fractures etiology, Spinal Fractures surgery, Surgery, Computer-Assisted adverse effects, Surgery, Computer-Assisted instrumentation, Time Factors, Treatment Outcome, Bone Screws, Fracture Fixation, Internal methods, Imaging, Three-Dimensional methods, Odontoid Process surgery, Surgery, Computer-Assisted methods
- Abstract
OBJECTIVE As odontoid process fractures become increasingly common in the aging population, a technical understanding of treatment approaches is critical. 3D image guidance can improve the safety of posterior cervical hardware placement, but few studies have explored its utility in anterior approaches. The authors present in a stepwise fashion the technique of odontoid screw placement using the Medtronic O-arm navigation system and describe their initial institutional experience with this surgical approach. METHODS The authors retrospectively reviewed all cases of anterior odontoid screw fixation for Type II fractures at an academic medical center between 2006 and 2015. Patients were identified from a prospectively collected institutional database of patients who had suffered spine trauma. A standardized protocol for navigated odontoid screw placement was generated from the collective experience at the authors' institution. Secondarily, the authors compared collected variables, including presenting symptoms, injury mechanism, surgical complications, blood loss, operative time, radiographically demonstrated nonunion rate, and clinical outcome at most recent follow-up, between navigated and nonnavigated cases. RESULTS Ten patients (three female; mean age 61) underwent odontoid screw placement. Most patients presented with neck pain without a neurological deficit after a fall. O-arm navigation was used in 8 patients. An acute neck hematoma and screw retraction, each requiring surgery, occurred in 2 patients in whom navigation was used. Partial vocal cord paralysis occurred after surgery in one patient in whom no navigation was used. There was no difference in blood loss or operative time with or without navigation. One patient from each group had radiographic nonunion. No patient reported a worsening of symptoms at follow-up (mean duration 9 months). CONCLUSIONS The authors provide a detailed step-by-step guide to the navigated placement of an odontoid screw. Their surgical experience suggests that O-arm-assisted odontoid screw fixation is a viable approach. Future studies will be needed to rigorously compare the accuracy and efficiency of navigated versus nonnavigated odontoid screw placement.
- Published
- 2017
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37. A longitudinal study of placental perfusion using dynamic contrast enhanced magnetic resonance imaging in murine pregnancy.
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Yadav BK, Neelavalli J, Krishnamurthy U, Szalai G, Shen Y, Nayak NR, Chaiworapongsa T, Hernandez-Andrade E, Than NG, Haacke EM, and Romero R
- Subjects
- Animals, Female, Mice, Placenta blood supply, Pregnancy, Magnetic Resonance Imaging, Placenta diagnostic imaging, Placental Circulation physiology
- Abstract
Introduction: To evaluate changes in placental perfusion with advancing gestation in normal murine pregnancy using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI)., Methods: Seven timed-pregnant CD-1 mice underwent DCE-MRI scanning longitudinally on gestational days (GD) 13, 15 and 17. Placentas were segmented into high (HPZ) and low perfusion zones (LPZ) using tissue similarity mapping. Blood perfusion of the respective regions and the whole placenta was quantified using the steepest slope method. The diameter of the maternal central canal (CC) was also measured., Results: An increase in perfusion was observed between GD13 and GD17 in the overall placenta (p = 0.04) and in the HPZ (p = 0.02). Although perfusion in the LPZ showed a slight increasing trend, it was not significant (p = 0.07). Perfusion, in units of ml/min/100 ml, in the overall placenta and the HPZ was respectively 61.2 ± 31.2 and 106.2 ± 56.3 at GD13 (n = 19 placentas); 90.3 ± 43.7 and 139 ± 55.4 at GD15 (n = 20); and 104.9 ± 76.1 and 172.2 ± 85.6 at GD17 (n = 14). The size of the CC increased with advancing gestation (p < 0.05)., Discussion: Using longitudinal DCE-MRI, the gestational age-dependent perfusion change in the normal murine placenta and in its regional compartments was quantified. In mid and late gestations, placental constituent regions differ significantly in their perfusion rates. The CC diameter also showed increase with advancing gestation, which may be playing an important role toward the gestational age-dependent increase in placental perfusion., (Copyright © 2016. Published by Elsevier Ltd.)
- Published
- 2016
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38. Chemical composition, pretreatments and saccharification of Senna siamea (Lam.) H.S. Irwin & Barneby: An efficient biomass producing tree legume.
- Author
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Mund NK, Dash D, Barik CR, Goud VV, Sahoo L, Mishra P, and Nayak NR
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- Cellulase metabolism, Cellulose metabolism, Chemical Fractionation methods, Fabaceae drug effects, Glucans metabolism, Glucose metabolism, Hydrolysis, Lignin metabolism, Particle Size, Phosphoric Acids pharmacology, Solvents, Time Factors, beta-Glucosidase metabolism, Biomass, Carbohydrate Metabolism drug effects, Fabaceae chemistry, Fabaceae metabolism
- Abstract
Protocols were developed for efficient release of glucose from the biomass of Senna siamea, one of the highly efficient biomass producing tree legumes. Composition of mature, 1year and 2years coppice biomass were analysed. For the hydrolysis of the glucan, two pretreatments, cellulose solvent- and organic solvent-based lignocellulose fractionation (COSLIF) and alkali (sodium hydroxide) were used; COSLIF (85% phosphoric acid, 45min incubation at 50°C) pretreated mature biomass exhibited best result in which 88.90% glucose released after 72h of incubation with the use of 5 filter paper units (FPU) of cellulase and 10 international units (IU) of β-glucosidase per gram of glucan. Of the biomass of different particle sizes (40-200mesh) used for saccharification, 40-60mesh shown the maximum glucose release. COSLIF pretreated mature, 1year and 2years coppice biomass showed equivalent glucose release profiles., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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39. Comparing Utility Scores in Common Spinal Radiculopathies: Results of a Prospective Valuation Study.
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Nayak NR, Stephen JH, Abdullah KG, Stein SC, and Malhotra NR
- Abstract
Study Design Prospective observational study. Objective To determine whether preference-based health utility scores for common spinal radiculopathies vary by specific spinal level. Methods We employed a standard gamble study using the general public to calculate individual preference-based quality of life for four common radiculopathies: C6, C7, L5, and S1. We compared utility scores obtained for each level of radiculopathy with analysis of variance and t test. Multivariable regression was used to test the effects of the covariates age, sex, and years of education. We also reviewed the literature for publications reporting EuroQol-5 Dimensions (EQ-5D) scores for patients with radiculopathy. Results Two hundred participants were included in the study. Average utility for the four spinal levels fell within a narrow range (0.748 to 0.796). There were no statistically significant differences between lumbar and cervical radiculopathies, nor were there significant differences among the different spinal levels (F = 0.0850, p = 0.086). Age and sex had no significant effect on utility scores. There was a significant correlation between years of education and utility values for S1 radiculopathy (p = 0.037). On review of the literature, no study separated utility values by specific spinal level. EQ-5D utilities for both cervical and lumbar radiculopathy were considerably lower than the results of our study. Conclusions Utility values associated with the most common levels of cervical and lumbar radiculopathy do not significantly differ from each other, validating the current practice of grouping utility by spinal segment rather than by specific root levels. The discrepancy in average utility values between our study and the EQ-5D highlights the need to be mindful of the underlying instruments used when assessing outcomes studies from different sources.
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- 2016
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40. Microsurgical treatment of sacral perineural (Tarlov) cysts: case series and review of the literature.
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Burke JF, Thawani JP, Berger I, Nayak NR, Stephen JH, Farkas T, Aschyan HJ, Pierce J, Kanchwala S, Long DM, and Welch WC
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- Adult, Female, Humans, Low Back Pain diagnostic imaging, Lumbosacral Region diagnostic imaging, Lumbosacral Region surgery, Magnetic Resonance Imaging, Male, Middle Aged, Paraspinal Muscles diagnostic imaging, Retrospective Studies, Tarlov Cysts diagnostic imaging, Treatment Outcome, Laminectomy methods, Low Back Pain surgery, Microsurgery methods, Paraspinal Muscles surgery, Tarlov Cysts surgery
- Abstract
OBJECTIVE Tarlov cysts (TCs) occur most commonly on extradural components of the sacral and coccygeal nerve roots. These lesions are often found incidentally, with an estimated prevalence of 4%-9%. Given the low estimated rates of symptomatic TC and the fact that symptoms can overlap with other common causes of low-back pain, optimal management of this entity is a matter of ongoing debate. Here, the authors investigate the effects of surgical intervention on symptomatic TCs and aim to solidify the surgical criteria for this disease process. METHODS The authors performed a retrospective review of data from consecutive patients who were surgically treated for symptomatic TCs from September 2011 to March 2013. Clinical evaluations and results from surveying pain and overall health were used. Univariate statistical analyses were performed. RESULTS Twenty-three adults (4 males, 19 females) who had been symptomatic for a mean of 47.4 months were treated with laminectomy, microsurgical exposure and/or imbrication, and paraspinous muscle flap closure. Eighteen patients (78.3%) had undergone prior interventions without sustained improvement. Thirteen patients (56.5%) underwent lumbar drainage for an average of 8.7 days following surgery. The mean follow-up was 14.4 months. Univariate analyses demonstrated that an advanced age (p = 0.045), the number of noted perineural cysts on preoperative imaging (p = 0.02), and the duration of preoperative symptoms (p = 0.03) were associated with a poor postoperative outcome. Although 47.8% of the patients were able to return to normal activities, 93.8% of those surveyed reported that they would undergo the operation again if given the choice. CONCLUSIONS This is one of the largest published studies on patients with TCs treated microsurgically. The data suggest that patients with symptomatic TCs may benefit from open microsurgical treatment. Although outcomes seem related to patient age, duration of symptoms, and extent of disease demonstrated on imaging, further study is warranted and underway.
- Published
- 2016
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41. Tracking patient-reported outcomes in spinal disorders.
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Nayak NR, Coats JM, Abdullah KG, Stein SC, and Malhotra NR
- Abstract
Background: Patient-reported outcome measures (PROMs) quantify health status from the patient's point of view. While the number of published outcomes studies grows each year, so too has the number of instruments being reported, leading to confusion on which instruments are appropriate to use for various spinal conditions., Methods: A broad search was conducted to identify commonly used PROMs in patients undergoing spinal surgery. We searched PubMed for combinations of terms related to anatomic location and a measure of patient-reported outcome in the title or text. We supplemented the search using the "related articles" feature of PubMed and by manually searching the bibliographies of selected articles., Results: Major categories of PROMs in spine surgery include health-related quality-of-life, pain, and disease-specific disability, for which several different instrument options were identified and detailed. The minimal clinically important difference varies between instruments and differentiates statistical significance from clinical significance. In addition, the accurate estimation of costs has become a challenging but intrinsically linked variable to outcomes as increased attention is paid to the relative value of surgical interventions., Conclusion: While a number of PROMs are available for tracking outcomes in spine surgery, only a handful appear to be widely used. At least one instrument from each category should be measured pre- and post-operatively to quantify treatment effect. In addition, while the primary goal is to select the most appropriate instruments for the patient's condition, one should keep in mind sustainability of efforts with regard to patient and administrative burden.
- Published
- 2015
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42. Aneurysmal vasculopathy in human-acquired immunodeficiency virus-infected adults: Imaging case series and review of the literature.
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Thawani JP, Nayak NR, Pisapia JM, Petrov D, Pukenas BA, Hurst RW, and Smith MJ
- Subjects
- Adult, Angiography, Digital Subtraction, CD4 Lymphocyte Count, Cerebral Angiography, Constriction, Pathologic, Female, Humans, Intracranial Aneurysm surgery, Male, Meningism etiology, Middle Aged, Muscle Weakness etiology, Neurosurgical Procedures methods, Prognosis, Retrospective Studies, Stents, HIV Infections complications, Intracranial Aneurysm diagnostic imaging, Intracranial Aneurysm etiology
- Abstract
Background: Intracranial vasculopathy in adult patients with human-acquired immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) is a rare but increasingly recognized disease entity., Objective: We aimed to contribute to and summarize the adult literature describing patients with HIV/AIDS who have intracranial vasculopathy., Methods: A retrospective review of adult patients with HIV/AIDS undergoing diagnostic cerebral angiography at our institution from 2007-2013 was performed. A literature review of relevant existing studies was performed., Results: Five adult patients with HIV-related aneurysmal and occlusive vasculopathy were diagnosed and/or treated at our institution. A comprehensive review of the literature yielded data from 17 series describing 28 adult patients with HIV/AIDS and intracranial vasculopathy. Our review suggests that low CD4 count, motor weakness, and meningismus may be associated with the sequelae of intracranial vasculopathy/vasculitis in patients with HIV/AIDS., Conclusion: Patients with HIV/AIDS who have aneurysmal and stenotic vascular disease may benefit from earlier surveillance with the onset of neurological symptoms. The roles of medical, open surgical, and endovascular therapy in this unique entity will be further defined as the pathological basis of the disease is better understood., (© The Author(s) 2015.)
- Published
- 2015
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43. Minimally Invasive Surgery for Traumatic Fractures in Ankylosing Spinal Diseases.
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Nayak NR, Pisapia JM, Abdullah KG, and Schuster JM
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Study Design Retrospective case series. Objective Ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH) are two related diseases that significantly increase the risk of unstable spinal fractures from seemingly trivial trauma. Given the older age and higher surgical risk profile of most of these patients, minimally invasive (MIS) approaches to the treatment of such fractures may reduce operative risk and physiologic stress. Methods Eleven consecutive patients with hyperextension thoracolumbar injuries and a diagnosis of AS or DISH admitted to a single level I trauma center between June 2009 and June 2014 were retrospectively reviewed. All patients were treated with MIS stabilization. In addition, the patients were administered the Oswestry Disability Index and EuroQol-5D surveys to evaluate patient-reported outcomes regarding disability and health-related quality of life, respectively. Results Of the 11 patients, 10 were alive at the time of review. The mean follow-up time was 28 months. The average age was 77 years old with a mean body mass index of 34. All patients had severe systemic disease, American Society of Anesthesiologists grade III, with multiple medical comorbidities. Seven segments on average were included in the operative construct. There were no instrumentation failures or nonunions requiring revision surgery. The average postoperative Oswestry disability index was 21.5% (range: 0 to 34%), corresponding to low to moderate disability, and the average EuroQol-5D utility score was 0.77 (range: 0.60 to 1), a similar average postoperative utility value to those published in the literature on elective surgery for degenerative lumbar conditions. Conclusions MIS stabilization, when used on patients with good preoperative neurologic status, can successfully manage spinal fractures in patients with AS and DISH and preserve a favorable postoperative quality of life with limited disability.
- Published
- 2015
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44. Advanced Multi-Axis Spine Testing: Clinical Relevance and Research Recommendations.
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Holsgrove TP, Nayak NR, Welch WC, and Winkelstein BA
- Abstract
Back pain and spinal degeneration affect a large proportion of the general population. The economic burden of spinal degeneration is significant, and the treatment of spinal degeneration represents a large proportion of healthcare costs. However, spinal surgery does not always provide improved clinical outcomes compared to non-surgical alternatives, and modern interventions, such as total disc replacement, may not offer clinically relevant improvements over more established procedures. Although psychological and socioeconomic factors play an important role in the development and response to back pain, the variation in clinical success is also related to the complexity of the spine, and the multi-faceted manner by which spinal degeneration often occurs. The successful surgical treatment of degenerative spinal conditions requires collaboration between surgeons, engineers, and scientists in order to provide a multi-disciplinary approach to managing the complete condition. In this review, we provide relevant background from both the clinical and the basic research perspectives, which is synthesized into several examples and recommendations for consideration in increasing translational research between communities with the goal of providing improved knowledge and care. Current clinical imaging, and multi-axis testing machines, offer great promise for future research by combining invivo kinematics and loading with in-vitro testing in six degrees of freedom to offer more accurate predictions of the performance of new spinal instrumentation. Upon synthesis of the literature, it is recommended that in-vitro tests strive to recreate as many aspects of the in-vivo environment as possible, and that a physiological preload is a critical factor in assessing spinal biomechanics in the laboratory. A greater link between surgical procedures, and the outcomes in all three anatomical planes should be considered in both the in-vivo and in-vitro settings, to provide data relevant to quality of motion, and stability.
- Published
- 2015
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45. Expression of interleukin-22 in decidua of patients with early pregnancy and unexplained recurrent pregnancy loss.
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O'Hern Perfetto C, Fan X, Dahl S, Krieg S, Westphal LM, Bunker Lathi R, and Nayak NR
- Subjects
- Adult, Female, Homeostasis, Humans, Killer Cells, Natural metabolism, Real-Time Polymerase Chain Reaction, Interleukin-22, Abortion, Habitual metabolism, Abortion, Spontaneous metabolism, Decidua metabolism, Interleukins metabolism
- Abstract
Purpose: Researchers have hypothesized that an imbalance of immune cells in the uterine decidua and a dysfunction in cytokines they produce may contribute to recurrent pregnancy loss (RPL). The objective of this study was to determine if IL-22, IL-23 and IL-17 are expressed abnormally in the decidua of patients with RPL compared to those women with a normal pregnancy. We also sought to confirm that uterine natural killer (uNK) cells are lower in the decidua of patients with RPL, as well as identify IL-22 expression by uNK cells., Methods: After meeting strict inclusion criteria, maternal decidua of nine patients with unexplained RPL and a confirmed euploid fetal loss, and 11 gestational age-matched patients undergoing elective pregnancy termination were included in our analysis. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed to quantify RNA expression, Western blot was performed to quantify protein expression and immunohistochemistry (IHC) was performed to identify IL-22 and uNK cells., Results: We found that women with unexplained RPL and a euploid fetal loss had significantly less gene and protein expression of IL-22 in the decidua. Additionally, we found that IL-22 is primarily expressed by uNK cells in the decidua., Conclusions: In conclusion, our results suggest that lower levels of IL-22 in the uterine decidua in patients with unexplained RPL may contribute to a disruption of decidual homeostasis and ultimately lead to early pregnancy loss.
- Published
- 2015
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46. Endoscopic approaches to brainstem cavernous malformations: Case series and review of the literature.
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Nayak NR, Thawani JP, Sanborn MR, Storm PB, and Lee JY
- Abstract
Background: Symptomatic cavernous malformations involving the brainstem are frequently difficult to access via traditional methods. Conventional skull-base approaches require significant brain retraction or bone removal to provide an adequate operative corridor. While there has been a trend toward limited employment of the most invasive surgical approaches, recent advances in endoscopic technology may complement existing methods to access these difficult to reach areas., Case Descriptions: Four consecutive patients were treated for symptomatic, hemorrhagic brainstem cavernous malformations via fully endoscopic approaches (endonasal, transclival; retrosigmoid; lateral supracerebellar, infratentorial; endonasal, transclival). Together, these lesions encompassed all three segments of the brainstem. Three of the patients had complete resection of the cavernous malformation, while one patient had stable residual at long-term follow up. Associated developmental venous anomalies were preserved in the two patients where one was identified preoperatively. Three of the four patients maintained stable or improved neurological examinations following surgery, while one patient experienced ipsilateral palsies of cranial nerves VII and VIII. The first transclival approach resulted in a symptomatic cerebrospinal fluid leak requiring re-operation, but the second did not. Although there are challenges associated with endoscopic approaches, relative to our prior microsurgical experience with similar cases, visualization and illumination of the surgical corridors were superior without significant limitations on operative mobility., Conclusion: The endoscope is a promising adjunct to the neurosurgeon's ability to approach difficult to access brainstem cavernous malformations. It allows the surgeon to achieve well-illuminated, panoramic views, and by combining approaches, can provide minimally invasive access to most regions of the brainstem.
- Published
- 2015
- Full Text
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47. Myofascial Closure of Intradural Inclusion Cysts following in utero Myelomeningocele Repair.
- Author
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Thawani JP, Nayak NR, Pisapia JM, Tahiri Y, Gebbia J, Adzick NS, Sutton LN, Taylor JA, and Heuer GG
- Subjects
- Dermoid Cyst etiology, Epidermal Cyst etiology, Female, Fetal Therapies adverse effects, Humans, Infant, Laminectomy, Lumbosacral Region pathology, Lumbosacral Region surgery, Neurosurgical Procedures adverse effects, Pregnancy, Spinal Cord Neoplasms etiology, Dermoid Cyst surgery, Epidermal Cyst surgery, Fetal Diseases surgery, Fetal Therapies methods, Meningomyelocele surgery, Neurosurgical Procedures methods, Paraspinal Muscles surgery, Postoperative Complications surgery, Spinal Cord Neoplasms surgery
- Abstract
Myelomeningocele is one of the most common congenital malformations. A randomized controlled trial, known as the Management of Myelomeningocele Study (MOMS), demonstrated that closure during the fetal period can be performed relatively safely and be of significant benefit to patients. However, postnatally, patients can develop resultant symptoms from a tethered cord and inclusion cysts; this often requires surgical treatment. Repeat surgery in this population can be challenging due to the age of the patients, the extent of surgical exposure needed and the need for resection of dermal and epidermal tissues in the midline. We describe our approach for closure of these complex defects using lateral fasciocutaneous flaps with relaxing incisions made in the posterior axillary line, in order to minimize tension and maximize soft tissue coverage of the midline., (© 2015 S. Karger AG, Basel.)
- Published
- 2015
- Full Text
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48. Endometrial VEGF induces placental sFLT1 and leads to pregnancy complications.
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Fan X, Rai A, Kambham N, Sung JF, Singh N, Petitt M, Dhal S, Agrawal R, Sutton RE, Druzin ML, Gambhir SS, Ambati BK, Cross JC, and Nayak NR
- Subjects
- Animals, Case-Control Studies, Enzyme Induction, Female, Gene Expression, Male, Mice, Pregnancy, Vascular Endothelial Growth Factor Receptor-1 genetics, Endometrium enzymology, Placenta enzymology, Pre-Eclampsia enzymology, Vascular Endothelial Growth Factor A physiology, Vascular Endothelial Growth Factor Receptor-1 metabolism
- Abstract
There is strong evidence that overproduction of soluble fms-like tyrosine kinase-1 (sFLT1) in the placenta is a major cause of vascular dysfunction in preeclampsia through sFLT1-dependent antagonism of VEGF. However, the cause of placental sFLT1 upregulation is not known. Here we demonstrated that in women with preeclampsia, sFLT1 is upregulated in placental trophoblasts, while VEGF is upregulated in adjacent maternal decidual cells. In response to VEGF, expression of sFlt1 mRNA, but not full-length Flt1 mRNA, increased in cultured murine trophoblast stem cells. We developed a method for transgene expression specifically in mouse endometrium and found that endometrial-specific VEGF overexpression induced placental sFLT1 production and elevated sFLT1 levels in maternal serum. This led to pregnancy losses, placental vascular defects, and preeclampsia-like symptoms, including hypertension, proteinuria, and glomerular endotheliosis in the mother. Knockdown of placental sFlt1 with a trophoblast-specific transgene caused placental vascular changes that were consistent with excess VEGF activity. Moreover, sFlt1 knockdown in VEGF-overexpressing animals enhanced symptoms produced by VEGF overexpression alone. These findings indicate that sFLT1 plays an essential role in maintaining vascular integrity in the placenta by sequestering excess maternal VEGF and suggest that a local increase in VEGF can trigger placental overexpression of sFLT1, potentially contributing to the development of preeclampsia and other pregnancy complications.
- Published
- 2014
- Full Text
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49. An Arabidopsis ATP-dependent, DEAD-box RNA helicase loses activity upon IsoAsp formation but is restored by PROTEIN ISOASPARTYL METHYLTRANSFERASE.
- Author
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Nayak NR, Putnam AA, Addepalli B, Lowenson JD, Chen T, Jankowsky E, Perry SE, Dinkins RD, Limbach PA, Clarke SG, and Downie AB
- Subjects
- Adenosine Triphosphate metabolism, Amino Acid Sequence, Arabidopsis genetics, Arabidopsis growth & development, Arabidopsis metabolism, Arabidopsis Proteins chemistry, Arabidopsis Proteins genetics, Circular Dichroism, DEAD-box RNA Helicases chemistry, DEAD-box RNA Helicases genetics, Enzyme Stability, Genetic Complementation Test, Hot Temperature, Humans, Isoaspartic Acid genetics, Mass Spectrometry, Molecular Sequence Data, Mutation, Nucleic Acid Denaturation, Plants, Genetically Modified, Protein Conformation, RNA chemistry, RNA genetics, RNA metabolism, Seeds genetics, Seeds metabolism, Sequence Homology, Amino Acid, Substrate Specificity, Arabidopsis Proteins metabolism, DEAD-box RNA Helicases metabolism, Isoaspartic Acid metabolism, Protein D-Aspartate-L-Isoaspartate Methyltransferase metabolism
- Abstract
Orthodox seeds are capable of withstanding severe dehydration. However, in the dehydrated state, Asn and Asp residues in proteins can convert to succinimide residues that can further react to predominantly form isomerized isoAsp residues upon rehydration (imbibition). IsoAsp residues can impair protein function and can render seeds nonviable, but PROTEIN ISOASPARTYL METHYLTRANSFERASE (PIMT) can initiate isoAsp conversion to Asp residues. The proteins necessary for translation upon imbibition in orthodox seeds may be particularly important to maintain in an active state. One such protein is the large, multidomain protein, Arabidopsis thaliana PLANT RNA HELICASE75 (PRH75), a DEAD-box helicase known to be susceptible to isoAsp residue accumulation. However, the consequences of such isomerization on PRH75 catalysis and for the plant are unknown. Here, it is demonstrated that PRH75 is necessary for successful seed development. It acquires isoAsp rapidly during heat stress, which eliminates RNA unwinding (but not rewinding) competence. The repair by PIMT is able to restore PRH75's complex biochemical activity provided isoAsp formation has not led to subsequent, destabilizing conformational alterations. For PRH75, an important enzymatic activity associated with translation would be eliminated unless rapidly repaired by PIMT prior to additional, deleterious conformational changes that would compromise seed vitality and germination.
- Published
- 2013
- Full Text
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50. Transient, inducible, placenta-specific gene expression in mice.
- Author
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Fan X, Petitt M, Gamboa M, Huang M, Dhal S, Druzin ML, Wu JC, Chen-Tsai Y, and Nayak NR
- Subjects
- Animals, Female, Luminescent Measurements, Mice, Mice, Transgenic, Pregnancy, Promoter Regions, Genetic, Gene Expression, Gene Transfer Techniques, Genes, Reporter, Placenta metabolism, Transgenes
- Abstract
Molecular understanding of placental functions and pregnancy disorders is limited by the absence of methods for placenta-specific gene manipulation. Although persistent placenta-specific gene expression has been achieved by lentivirus-based gene delivery methods, developmentally and physiologically important placental genes have highly stage-specific functions, requiring controllable, transient expression systems for functional analysis. Here, we describe an inducible, placenta-specific gene expression system that enables high-level, transient transgene expression and monitoring of gene expression by live bioluminescence imaging in mouse placenta at different stages of pregnancy. We used the third generation tetracycline-responsive tranactivator protein Tet-On 3G, with 10- to 100-fold increased sensitivity to doxycycline (Dox) compared with previous versions, enabling unusually sensitive on-off control of gene expression in vivo. Transgenic mice expressing Tet-On 3G were created using a new integrase-based, site-specific approach, yielding high-level transgene expression driven by a ubiquitous promoter. Blastocysts from these mice were transduced with the Tet-On 3G-response element promoter-driving firefly luciferase using lentivirus-mediated placenta-specific gene delivery and transferred into wild-type pseudopregnant recipients for placenta-specific, Dox-inducible gene expression. Systemic Dox administration at various time points during pregnancy led to transient, placenta-specific firefly luciferase expression as early as d 5 of pregnancy in a Dox dose-dependent manner. This system enables, for the first time, reliable pregnancy stage-specific induction of gene expression in the placenta and live monitoring of gene expression during pregnancy. It will be widely applicable to studies of both placental development and pregnancy, and the site-specific Tet-On G3 mouse will be valuable for studies in a broad range of tissues.
- Published
- 2012
- Full Text
- View/download PDF
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