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Anxiety disorders are psychiatric conditions characterized by prolonged and generalized anxiety experienced by individuals in response to various events or situations. At present, anxiety disorders are regarded as the most widespread psychiatric disorders globally. Medication and different types of psychotherapies are employed as the primary therapeutic modalities in clinical practice for the treatment of anxiety disorders. However, combining these two approaches is known to yield more significant benefits than medication alone. Nevertheless, there is a lack of resources and a limited availability of psychotherapy options in underdeveloped areas. Psychotherapy methods encompass relaxation techniques, controlled breathing exercises, visualization exercises, controlled exposure exercises, and cognitive interventions such as challenging negative thoughts. These methods are vital in the treatment of anxiety disorders, but executing them proficiently can be demanding. Moreover, individuals with distinct anxiety disorders are prescribed medications that may cause withdrawal symptoms in some instances. Additionally, there is inadequate availability of face-to-face psychotherapy and a restricted capacity to predict and monitor the health, behavioral, and environmental aspects of individuals with anxiety disorders during the initial phases. In recent years, there has been notable progress in developing and utilizing artificial intelligence (AI) based applications and environments to improve the precision and sensitivity of diagnosing and treating various categories of anxiety disorders. As a result, this study aims to establish the efficacy of AI-enabled environments in addressing the existing challenges in managing anxiety disorders, reducing reliance on medication, and investigating the potential advantages, issues, and opportunities of integrating AI-assisted healthcare for anxiety disorders and enabling personalized therapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Das and Gavade.)

Phosphorus to an optimum extent is an essential nutrient for all living organisms and its scarcity may cause food security, and environmental preservation issues vis-à-vis agroeconomic hurdles. Undesirably excess phosphorus intensifies the eutrophication problem in non-marine water bodies and disrupts the natural nutrient balance of the ecosystem. To overcome such dichotomy, biodegradable polymer-based adsorbents have emerged as a cost-effective and implementable approach in striking a "desired optimum-undesired excess" balance pertaining to phosphate in a sustainable manner. So far, the reports on adopting such adsorbent-approach for wastewater remediation remained largely scattered, unstructured, and poorly correlated. In this background, the contextual review comprehensively discusses the current state-of-the-art in utilizing biodegradable polymeric frameworks as an adsorbent system for phosphate removal and its efficient recovery from the aquatic ecosystem, while highlighting their characteristics-specific functional efficiency vis-à-vis easiness of synthetic and commercial viability. The overview further delves into the sources and environmental ramifications of excessive phosphorus in water bodies and associated mechanistic pathways of phosphorus removal via adsorption, precipitation, and membrane filtration enabled by biodegradable (natural and synthetic) polymeric substrates. Finally, functionality optimization, degradability tuning, and adsorption selectivity of biodegradable polymers are highlighted, while aiming to strike a balance in "removal-recovery-reuse" dynamics of phosphate. Thus, the current review not only paves the way for future exploration of biodegradable polymers in sustainable cost-effective adsorbents for phosphorus removal but also can serve as a guide for researchers dealing with this critical issue., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Forecasting stock market indices is challenging because stock prices are usually nonlinear and non- stationary. COVID-19 has had a significant impact on stock market volatility, which makes forecasting more challenging. Since the number of confirmed cases significantly impacted the stock price index; hence, it has been considered a covariate in this analysis. The primary focus of this study is to address the challenge of forecasting volatile stock indices during Covid-19 by employing time series analysis. In particular, the goal is to find the best method to predict future stock price indices in relation to the number of COVID-19 infection rates. In this study, the effect of covariates has been analyzed for three stock indices: S & P 500, Morgan Stanley Capital International (MSCI) world stock index, and the Chicago Board Options Exchange (CBOE) Volatility Index (VIX). Results show that parametric approaches can be good forecasting models for the S & P 500 index and the VIX index. On the other hand, a random walk model can be adopted to forecast the MSCI index. Moreover, among the three random walk forecasting methods for the MSCI index, the naïve method provides the best forecasting model., Competing Interests: Kumer P. Das is an Academic Editor for PeerJ., (©2023 Patwary and Das.)

Brachial plexus injury is not uncommon in our country like Bangladesh and it causes functional damage and physical disability of the upper limbs. Most of the cases were caused by motor vehicle accident. We have conducted a prospective study for the operative treatment of 105 adult traumatic brachial plexus injury cases in Hand unit in the department of Orthopaedics, Bangabandhu Sheikh Mujib Medial University (BSMMU) during January 2012 to July 2019. The main surgical options for brachial plexus injury include primary reconstructive surgery such as neurolysis, direct repair, nerve graft, nerve transfer (neurotization) and possibly free functioning (gracilis) muscle transfer and secondary reconstructive procedure such as tendon transfer, arthrodesis, FFMT and bony procedure. Each of these procedures is used either alone or in combination for particular clinical scenarios. Aims and objectives of this study was to restoration of shoulder abduction and external rotation, elbow flexion and hand function are goal of treatment of adult traumatic brachial plexus injury. Age range was from 14 years to 55 years (mean age 26 years). Male were 95 and female were 10 cases. Time from trauma to surgery was valid 3 months to 9 months. Motor cycle accident was most common mechanism of injury. Upper plexus (C5, C6) injury was 52 cases, extended upper plexus (C5, C6 & C7) injury was 19 cases and global brachial plexus injury was 34 cases. When there is high suspicion of root avulsions, early exploration and reconstruction is indicated. Operate these patients 2-3 months after their injury. In other patients without high suspicion of root avulsion, we routinely perform exploration between 3 to 6 months after injury when no adequate sign of recovery are present. Common reconstructive options are any injury with neuroma in continuity with conductive nerve action potential (NAP): only neurolysis or any injury with nerve rupture or postganglionic neuroma not conducting nerve Action potential (NAP) and good proximal nerve: Direct repair or repair with nerve graft or nerve transfer if possible. Follow up period from 6 months to 6 years. The best results were obtained in C5, C6 and C5, C6 & C7 brachial plexus injury cases. SAN to SSN, Oberlin II and long head triceps motor branch to anterior division of axillary nerve transfer for C5 & C6 injury or upper plexus injury and in addition intercostals nerve to anterior division of axillary nerve and AIN branch of median nerve to ECRB for C5, C6 & C7 (extended upper plexus injury). Extra-plexus and intra-plexus neurotization was done in global brachial plexus injury cases and 5 cases by contra-lateral C7 to median nerve by vascularised ulnar nerve graft and only 2 cases contra-lateral C7 to lower trunk through pre spinal or pre tracheal route were done and only one case by FFMT. Few cases gain shoulder abduction and elbow flexion but no improvement of hand function and most cases even by FFMT still in follow up. Results of surgical treatment of upper and extended upper brachial plexus injury cases were satisfactory on the other hand recovery of shoulder abduction and elbow flexion was acceptable and comparable to other study in global brachial plexus injury and recovery of hand function were poor.

Cancer is a life-threatening disease, resulting in nearly 10 million deaths worldwide. There are various causes of cancer, and the prognostic information varies in each patient because of unique molecular signatures in the human body. However, genetic heterogeneity occurs due to different cancer types and changes in the neoplasms, which complicates the diagnosis and treatment. Targeted drug delivery is considered a pivotal contributor to precision medicine for cancer treatments as this method helps deliver medication to patients by systematically increasing the drug concentration on the targeted body parts. In such cases, nanoparticle-mediated drug delivery and the integration of artificial intelligence (AI) can help bridge the gap and enhance localized drug delivery systems capable of biomarker sensing. Diagnostic assays using nanoparticles (NPs) enable biomarker identification by accumulating in the specific cancer sites and ensuring accurate drug delivery planning. Integrating NPs for cancer targeting and AI can help devise sophisticated systems that further classify cancer types and understand complex disease patterns. Advanced AI algorithms can also help in biomarker detection, predicting different NP interactions of the targeted drug, and evaluating drug efficacy. Considering the advantages of the convergence of NPs and AI for targeted drug delivery, there has been significantly limited research focusing on the specific research theme, with most of the research being proposed on AI and drug discovery. Thus, the study's primary objective is to highlight the recent advances in drug delivery using NPs, and their impact on personalized treatment plans for cancer patients. In addition, a focal point of the study is also to highlight how integrating AI, and NPs can help address some of the existing challenges in drug delivery by conducting a collective survey., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Das and J.)

Tumors in the hand are relatively uncommon but 95% are benign. Tumors occurring in the hand, forearm and arm often have unique growth patterns and potential for metastasis that may be different from those seen elsewhere in the body. Secondary metastatic tumors in the hand are very rare (0.1%). Diagnosis is mainly clinical, but X-ray, USG and MRI help as a diagnostic aid. The aim of the study was to early diagnosis, see the pattern and proper management of the hand tumor and ensure good hand function. This prospective study was done from January 2004 to July 2019. We found 220 hand tumors in the hand unit, Department of Orthopaedic Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka Bangladesh. Among 220 patients, male were 114(51.81%) and female were 106 (48.19%). Out of 220 patients we found 190(86.36%) benign tumor and tumor like lesions and 30(13.64%) was malignant hand tumors. Out of 190 benign lesions, benign tumor was 158(83.15%) and 32(16.85%) was tumor like lesions. Among 158 benign tumor, bone tumors were 40(25.31%) and soft tissue tumours were 138(74.69%). Out of soft tissue tumor, peripheral nerve tumor was 20(12.66%). Enchondroma and Giant cell tumors are the most common among the benign bone tumors, on the other hand giant cell tumors of tendon sheath, Glomus tumor, haemangioma, neurofibroma, schwanoma are the common soft tissue tumors. Compound palmar ganglion, fibromatosis and tuberculosis of phalanx are the most common tumor like lesions. Synovial sarcoma 10(33.33%), osteosarcoma 03(10%), chondrosarcoma 03(10%), ewings sarcoma 02(6.66%), fibrosarcoma 04 (13.33%), Malignant fibrous histocytoma 01(3.33%), soft tissue sarcoma 01(3.33%), Merkel cell tumor 01(3.33%), pleomorphic Rabdomyosarcoma 01(3.33%), malignant melanoma 01(3.33%), clear cell sarcoma of tendon and aponeurosis 01(3.33%), undifferentiated carcinoma 01(3.33%) and extra skeletal chondro sarcoma 01(3.33%) were the malignant tumors. Most of the benign lesions recovered fully after excision except neurofibroma and malignant tumors were treated with excision (including amputation) and chemo-radiotherapy successfully, but 4 patients were refereed to higher center due to recurrence and deteriation of hand function and one patient died due to metastasis. Malignant hand tumor management is very difficult even after amputation with multidisciplinary approach. Hand tumor is uncommon and malignant tumors are rare but any abnormal lump or bump in the hand or wrist is considered as tumor. Early detection and intervention are essential for better prognosis and survival for malignant tumors of hands and upper limbs.

Avascular necrosis (AVN) of femoral head is an increasingly common cause of musculoskeletal disability. Most of the cases caused by steroid induced and traumatic but idiopathic cause are not also uncommon. Almost all the patients presented with pain at the hip, limping gait, restricted movement and difficulty in waking and squatting and becomes disabled. Core decompression and muscle pedicle bone graft at stage IIA, IIB and III provides painless and mobile life. Core decompression supplemented with bone graft to enhance mechanical support and augment healing. We have started a prospective study for the treatment of AVN of Femoral head at stage IIA, IIB and III by core decompression and Tensor fascia lata muscle pedicle bone graft in the department of Orthopaedic surgery Bangabandhu Seikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2009 to December 2019. Aim of the study was to assess the effectiveness of core decompression and tensor fascia lata muscle pedicle bone graft in the treatment of AVN of femoral head at stage IIA, IIB and III. A total 48 patients and 65 hips were operated. Out of 48 patients, male was 30(62.50%) and female was 18(37.5%). Male-Female ratio was 1.66:1. Age of the patients ranging from 20 years to 50 years, mean age 36±4.65 years. According to aetiology corticosteroid induced was 47/65 (72.31%), idiopathic was 8(12.31%), post traumatic was 4(6.15%), ITP was 2(3.08%), ALL was 2(3.08%), and alcohol induced was 2(3.08%) of femoral head involvement. According to Ficat and Arlet's staging, stage IIA hip involvement was 28/65(43.08%), stage IIB was 32(49.23%) and stage III was 5(07.69%). All patients were treated with core decompression along with tensor fascia lata (TFL) muscle pedicle bone graft. All patients were followed clinically and radiologically at regular interval. Follow up period was 6 months to 10 years. Harris hip score (HHS) was used for evaluation of clinical outcome. Among the 65 hips, 24(36.92%) was excellent outcome (HHS >90), 30(46.15%) was good outcome (HHS: 80-90), 7(10.78%) was fair outcome (HHS: 70-79) and 4(6.15%) was poor outcome. For valid statistical analysis excellent and good results were grouped as satisfactory that was 54(83.07%) and fair and poor results were grouped as unsatisfactory that was11(16.93%), p value is <0.001 that is significant. It has been concluded that core decompression and TFL muscle pedicle bone graft is a pain relieving, head preserving procedure and improve hip function for the management of AVN of femoral head in stage IIA, IIB and III.

COVID-19 caused by SARS-CoV-2 virus has had profound impact on the world in the past two years. Intense research is going on to find effective drugs to combat the disease. Over the past year several vaccines were approved for immunization. But SARS-CoV-2 being an RNA virus is continuously mutating to generate new variants, some of which develop features of immune escape. This raised serious doubts over the long-term efficacy of the vaccines. We have identified a unique mannose binding plant lectin from Narcissus tazetta bulb, NTL-125, which effectively inhibits SARS-CoV-2 replication in Vero-E6 cell line. In silico docking studies revealed that NTL-125 has strong affinity to viral Spike RBD protein, preventing it from attaching to hACE2 receptor, the gateway to cellular entry. Binding analyses revealed that all the mutant variants of Spike protein also have stronger affinity for NTL-125 than hACE2. The unique α-helical tail of NTL-125 plays most important role in binding to RBD of Spike. NTL-125 also interacts effectively with some glycan moieties of S-protein in addition to amino acid residues adding to the binding strength. Thus, NTL-125 is a highly potential antiviral compound of natural origin against SARS-CoV-2 and may serve as an important therapeutic for management of COVID-19., (Copyright © 2022. Published by Elsevier B.V.)

We develop a novel temporal complex network approach to quantify the US county level spread dynamics of COVID-19. We use both conventional econometric and Machine Learning (ML) models that incorporate the local spread dynamics, COVID-19 cases and death, and Google search activities to assess if incorporating information about local spreads improves the predictive accuracy of models for the US stock market. The results suggest that COVID-19 cases and deaths, its local spread, and Google searches have impacts on abnormal stock prices between January 2020 to May 2020. Furthermore, incorporating information about local spread significantly improves the performance of forecasting models of the abnormal stock prices at longer forecasting horizons., 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., (© 2021 Published by Elsevier B.V.)

This paper provides an analysis of the effect of the COVID-19 outbreak on the crude oil price. Using a newly developed air mobility index and Apple's driving trends index, we assess the effect of human mobility restrictions and social distancing during the COVID-19 pandemic on the crude oil price. We apply a quantile regression model, which evaluates different quantiles of the crude oil price. We also conduct an extreme value modeling, which examines the lower tail of the crude oil price distribution. We find that both the air mobility index and driving trends index significantly influence lower and upper quantiles of the WTI crude oil price. The extreme value models suggest that there is a potential risk of a negative crude oil price for a sudden extreme fall of air mobility., (© Grace Scientific Publishing 2022.)

The unforeseen outbreak of the COVID-19 epidemic has significantly stipulated the use of plastics to minimize the exposure and spread of the novel coronavirus. With the onset of the vaccination drive, the issue draws even more attention due to additional demand for vaccine packaging, transport, disposable syringes, and other allied devices scaling up to many million tonnes of plastic. Plastic materials in personal protective equipment (PPE), disposable pharmaceutical devices, and packaging for e-commerce facilities are perceived to be a lifesaver for the frontline healthcare personnel and the general public amidst recurring waves of the pandemic. However, the same material poses a threat as an evil environmental polluter when attributed to its indiscriminate and improper littering as well as mismanagement. The review not only highlights the environmental consequences due to the excessive use of disposable plastics amidst COVID-19 but also recommends mixed approaches to its management by adopting the combined and step-by-step methodology of adequate segregation, sterilization, sanitization activities, technological intervention, and process optimization measures. The overview finally concludes with some crucial way-forward measures and recommendations like the development of bioplastics and focusing on biodegradable/bio-compostable material alternatives to holistically deal with future pandemics., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Per- and polyfluoroalkyl substances (PFAS) are organic chemicals with wide industrial and consumer uses. They are found ubiquitously at low levels in the environment and are detectable in humans and wildlife. Perfluorobutane Sulfonate (PFBS) is a short-chained PFAS used to replace perfluorooctane sulfonate in commerce. In general, the rate of clearance for the short-chained PFAS is faster than that for the long-chained congeners. This study evaluated the pharmacokinetic properties of PFBS and its hepatic transcriptional responses in CD-1 mice. Males and females were given PFBS by oral gavage at 30 or 300 mg/kg; controls received 0.5 % Tween-20 vehicle. Trunk blood was collected at 0.5, 1, 2, 4, 8, 16 and 24 h thereafter; liver and kidney were also harvested. Serum and tissue concentrations of PFBS were determined by HPLC-MS-MS. Expression of several hepatic nuclear receptor target genes was determined by qPCR. The half-life of PFBS was estimated as 5.8 h in the males and 4.5 h in the females. Tmax was reached within 1-2 h. Volume of distribution was similar between the two sexes (0.32-0.40 L/kg). The rate of PFBS clearance was linear with exposure doses. Within 24 h, serum PFBS declined to less than 5 % of Cmax. PFBS was detected in liver or kidney, although tissue levels of the chemical were only a fraction of those in serum. At 24 h after administration of 300 mg/kg PFBS, elevated expression of several hepatic genes targeted for PPARα, PPARy, and PXR but not by AhR, LXR or CAR was observed, with responses indistinguishable between males and females. Little to no transcriptional response was seen with the 30 mg/kg dose. The short serum half-lives of PFBS (4-5 h) in mice were comparable to those reported in rats. Although detection of PFBS in liver was low compared to that in serum even at the 300 mg/kg dose, the tissue level was sufficient to activate several hepatic nuclear receptors, which may represent an acute response to the chemical at a high dose., 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 © 2020. Published by Elsevier B.V.)

Osteoarticular allografts have provided the chance of limb-sparing trial in tumor surgery. Several authors have reported 50-75% long term (>10 years) successful use of these types of grafts, and large well recognized series provide confirmation that limb reconstruction following extensive resection of bone and joints has been possible with their use. Infection has been a major problem, affecting up to 12 per cent of recipients and often resulting in re-operations and infrequently amputations. This prospective Interventional study was conducted in the Department of Orthopaedic Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU) and Biomedical Research division, Atomic Energy Centre, Savar, Dhaka, Bangladesh from January 2008 to December 2017. In this study patients' age were 20-50 years and male was 12(60%) & female was 8(40%). We assessed the results of 20 limb-salvage procedures (Resection-Arthrodesis Procedure) using 11-18cm of distal femur or proximal tibial osteoarticular allografts after wide resection of aggressive or malignant Giant Cell Tumour (GCT) around the knee joint, Campanacci Grade III or recurrent case of Campanacci Grade II. At the ten-year follow-up, two patients had died, one due to infection and tumor metastasis to the lungs and one due to medical causes. The allografts survived for more than five years was twelve patients (60%) all of whom had good function, ranging from 73% to 90% of normal. The allografts were removed because of fracture in two patients and infection in two patients. Remaining three patients allograft was survived with satisfactory function but follow up was 3 years. All postoperative problems related to the allograft reconstruction were documented. Functional outcome was evaluated using the Musculoskeletal Tumour Society Scoring System and at least more than 3 years follow up should be taken for categorization of the results. Among the 20 patients, satisfactory result was 15(75%) patients and unsatisfactory result was 5(25%) patients. P value was <0.001.

Background: Cleft palate (CP) is a common birth defect, occurring in an estimated 1 in 1,000 births worldwide. The secondary palate is formed by paired palatal shelves, consisting of a mesenchymal core with an outer layer of epithelial cells that grow toward each other, attach, and fuse. One of the mechanisms that can cause CP is failure of fusion, that is, failure to remove the epithelial seam between the palatal shelves to allow the mesenchyme confluence. Epidermal growth factor (EGF) plays an important role in palate growth and differentiation, while it may impede fusion., Methods: We developed a 3D organotypic model using human mesenchymal and epithelial stem cells to mimic human embryonic palatal shelves, and tested the effects of human EGF (hEGF) on proliferation and fusion. Spheroids were generated from human umbilical-derived mesenchymal stem cells (hMSCs) directed down an osteogenic lineage. Heterotypic spheroids, or organoids, were constructed by coating hMSC spheroids with extracellular matrix solution followed by a layer of human progenitor epithelial keratinocytes (hPEKs). Organoids were incubated in co-culture medium with or without hEGF and assessed for cell proliferation and time to fusion., Results: Osteogenic differentiation in hMSC spheroids was highest by Day 13. hEGF delayed fusion of organoids after 12 and 18 hr of contact. hEGF increased proliferation in organoids at 4 ng/ml, and proliferation was detected in hPEKs alone., Conclusion: Our results show that this model of human palatal fusion appropriately mimics the morphology of the developing human palate and responds to hEGF as expected., (Published 2018. This article is a U.S. Government work and is in the public domain in the USA.)

Background: αA- and αB- crystallin are members of small heat shock protein family with chaperone property. Their interactions with Cu2+ ions are reported in neurodegenerative diseases. We have been studying the effect of small ionic molecules on the stability of α-crystallin. Cu2+ is co-ordinated with αB-crystallin involving three histidine residues and one aspartic acid residue as potential binding sites. However, copper binding sites for the oligomeric native protein αA-crystallin protein is not known., Objective: The objective of this study was to study oligomerization and stability of αA- and αBcrystallin in presence and absence of Cu2+ ions and to find binding sites of Cu2+ on αA-crystallin., Methods: The recombinant Human αA- and αB-crystallin proteins were purified after overexpression from the E. coli BL21DE3 cell lysate by a combination of ion-exchange and gel filtration chromatography. Mass analysis of αA- and αB-crystallin in absence and presence of Cu2+ were carried out by MALDI TOF MS. Stability of αA-crystallin in presence and absence of Cu2+ was determined by equilibrium urea denaturation experiments. The equilibrium urea unfolding profiles of the αA-crystallin in absence and presence of different Cu2+ concentrations were fitted according to the three state model of protein unfolding. Dynamic Light Scattering (DLS) measurements were carried out to detect the oligomeric size of αA-crystallin in presence and absence of Cu2+ during urea unfolding. Histidine residues were modified by DEPC (Diethyl pyro carbonate). Chemically modified and unmodified αA-crystallin was digested by trypsin prior to MALDI MS analysis. Cu2+ pre-incubation was done before the chemical modification., Results: Mass spectrometric detection of intact protein allows direct measurement of Cu2+ ions bound to the protein. Thus the average numbers of Cu2+ bound to αA- and αB-crystallin were 4.2 and 3.6 respectively per subunit. It is seen that in presence of Cu2+ ions the free energy (ΔG) of unfolding of αA-crystallin almost doubled. The size analysis by dynamic light scattering data clearly indicated that in presence of Cu2+ ions the oligomeric size remain unchanged with increasing urea solutions. Mass spectrometric detection with chemical modification of histidine residues of αA-crystallin in presence and absence of Cu2+ indicated that amino acid residues H107, H100, H115 of αA-crystallin are involved in Cu2+ binding., Conclusion: Our results indicated that Cu2+ helped in increasing stability of αA-crystallin and three histidine residues H100, H107 and H115 of αA-crystallin are Cu2+ binding residues., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Perfluoroalkyl acids (PFAAs) are ubiquitous and persistent environmental contaminants. Compounds such as perfluoroocanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS) are readily found in the tissues of humans and wildlife. While PFOA and PFOS have been the subject of numerous studies since they were first described over a decade ago, less is known about the biological activity of PFHxS and PFNA. Most PFAAs are activators of peroxisome proliferator-activated receptor α (PPARα), although the biological effects of these compounds are likely mediated by other factors in addition to PPARα. To evaluate the effects of PFHxS and PFNA, male wild-type and Pparα-null mice were dosed by oral gavage with PFHxS (3 or 10mg/kg/day), PFNA (1 or 3mg/kg/day), or vehicle for 7days, and liver gene expression was evaluated by full-genome microarrays. Gene expression patterns were then compared to historical in-house data for PFOA and PFOS in addition to the experimental hypolipidemic agent, WY-14,643. While WY-14,643 altered most genes in a PPARα-dependent manner, approximately 11-24% of regulated genes in PFAA-treated mice were independent of PPARα. The possibility that PFAAs regulate gene expression through other molecular pathways was evaluated. Using data available through a microarray database, PFAA gene expression profiles were found to exhibit significant similarity to profiles from mouse tissues exposed to agonists of the constitutive activated receptor (CAR), estrogen receptor α (ERα), and PPARγ. Human PPARγ and ERα were activated by all four PFAAs in trans-activation assays from the ToxCast screening program. Predictive gene expression biomarkers showed that PFAAs activate CAR in both genotypes and cause feminization of the liver transcriptome through suppression of signal transducer and activator of transcription 5B (STAT5B). These results indicate that, in addition to activating PPARα as a primary target, PFAAs also have the potential to activate CAR, PPARγ, and ERα as well as suppress STAT5B., (Published by Elsevier B.V.)

Persistent presence of perfluoroalkyl acids (PFAAs) in the environment is due to their extensive use in industrial and consumer products, and their slow decay. Biochemical tests in rodent demonstrated that these chemicals are potent modifiers of lipid metabolism and cause hepatocellular steatosis. However, the molecular mechanism of PFAAs interference with lipid metabolism remains to be elucidated. Currently, two major hypotheses are that PFAAs interfere with mitochondrial beta-oxidation of fatty acids and/or they affect the transcriptional activity of peroxisome proliferator-activated receptor α (PPARα) in liver. To determine the ability of structurally-diverse PFAAs to cause steatosis, as well as to understand the underlying molecular mechanisms, wild-type (WT) and PPARα-null mice were treated with perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), or perfluorohexane sulfonate (PFHxS), by oral gavage for 7days, and their effects were compared to that of PPARα agonist WY-14643 (WY), which does not cause steatosis. Increases in liver weight and cell size, and decreases in DNA content per mg of liver, were observed for all compounds in WT mice, and were also seen in PPARα-null mice for PFOA, PFNA, and PFHxS, but not for WY. In Oil Red O stained sections, WT liver showed increased lipid accumulation in all treatment groups, whereas in PPARα-null livers, accumulation was observed after PFNA and PFHxS treatment, adding to the burden of steatosis observed in control (untreated) PPARα-null mice. Liver triglyceride (TG) levels were elevated in WT mice by all PFAAs and in PPARα-null mice only by PFNA. In vitro β-oxidation of palmitoyl carnitine by isolated rat liver mitochondria was not inhibited by any of the 7 PFAAs tested. Likewise, neither PFOA nor PFOS inhibited palmitate oxidation by HepG2/C3A human liver cell cultures. Microarray analysis of livers from PFAAs-treated mice indicated that the PFAAs induce the expression of the lipid catabolism genes, as well as those involved in fatty acid and triglyceride synthesis, in WT mice and, to a lesser extent, in PPARα-null mice. These results indicate that most of the PFAAs increase liver TG load and promote steatosis in mice We hypothesize that PFAAs increase steatosis because the balance of fatty acid accumulation/synthesis and oxidation is disrupted to favor accumulation., (Published by Elsevier B.V.)

Abscisic acid (ABA) acts as an important plant hormone in regulating various aspects of plant growth and developmental processes particularly under abiotic stress conditions. An increased ABA level in plant cells inhibits DNA replication and cell division, causing plant growth retardation. In this study, we have investigated the effects of ABA on the growth responses of some major loss-of-function mutants of DNA double-stand break (DSB) repair genes in Arabidopsis during seed germination and early stages of seedling growth for understanding the role of ABA in the induction of genome instability in plants. A comparative analysis of ABA sensitivity of wild-type Arabidopsis and the knockout mutant lines related to DSB sensors, including atatm, atatr, the non-homologous end joining (NHEJ) pathway genes, and mutants related to homologous recombination (HR) pathway genes showed relatively enhanced sensitivity of atatr and HR-related mutants to ABA treatment. The expression levels of HR-related genes were increased in wild-type Arabidopsis (Col-0) during seed germination and early stages of seedling growth. Immunoblotting experiments detected phosphorylation of histone H2AX in wild-type (Col-0) and DSB repair gene mutants after ABA treatment, indicating the activation of DNA damage response due to ABA treatment. Analyses of DSB repair kinetics using comet assay under neutral condition have revealed comparatively slower DSB repair activity in HR mutants. Overall, our results have provided comprehensive information on the possible effect of ABA on DNA repair machinery in plants and also indicated potential functional involvement of HR pathway in repairing ABA induced DNA damage in Arabidopsis., Competing Interests: The authors have declared that no competing interests exist.

The aggregation of insulin into amyloid fibers has been a limiting factor in the development of fast acting insulin analogues, creating a demand for excipients that limit aggregation. Despite the potential demand, inhibitors specifically targeting insulin have been few in number. Here we report a non-toxic and serum stable-designed heptapeptide, KR7 (KPWWPRR-NH 2 ), that differs significantly from the primarily hydrophobic sequences that have been previously used to interfere with insulin amyloid fibrillation. Thioflavin T fluorescence assays, circular dichroism spectroscopy, and one-dimensional proton NMR experiments suggest KR7 primarily targets the fiber elongation step with little effect on the early oligomerization steps in the lag time period. From confocal fluorescence and atomic force microscopy experiments, the net result appears to be the arrest of aggregation in an early, non-fibrillar aggregation stage. This mechanism is noticeably different from previous peptide-based inhibitors, which have primarily shifted the lag time with little effect on later stages of aggregation. As insulin is an important model system for understanding protein aggregation, the new peptide may be an important tool for understanding peptide-based inhibition of amyloid formation., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

The aim of this study is to assess the optimum rehabilitation and the functional outcome of open repaired Achilles tendon ruptures. This study was conducted for the 18 consecutive patients of complete ruptures at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from 2012 to 2013. Two groups were considered during 6 to 18 months post-operative observation and each group consist 9 patients. In the Group I, modified Teuffer's and in Group II, Lindholm operative methods were employed for the open repair of Achille tendon. The post operative outcomes were assessed for both of the groups through the modified Thermann's scores. In this study the patients median age was seen 39 years with 72.2% male and 27.8% female. The Thompson test was found positive in pre-operative and negative in post-operative outcome. The results shown that Achilles tendon ruptures occurred in 4 to 6cm rupture site, where the rupture side was 61.1% left and 38.9% right. The subjective overall assessment of total Thermann's scores were found very good (91 to 96) in 4 cases and (90 to 98) in 3 cases for Group I and Group II, respectively. Both of the operative techniques were found accountable results for rehabilitation. Therefore, based on the further statistical evidence of higher correlations and errors it may be concluded that Achilles tendon ruptures can be treated by modified Teuffer's or Lindholm technique.

Fracture of tibial shaft is the commonest site of long bone fractures due to its superficial location involving young or middle-age people. Proper management is an important issue regarding the future effective movements. In this study patients were grouped in closed Intra medullary interlocking nailing and locking compression plating. Post-operative follow up at 2 weeks, 6 weeks, 12 weeks and 3 months thereafter up to 6 months were done. Each of the patients was evaluated clinically and radiologically by tucker criteria of Tuker et al. Patients were assessed for pain on full weight bearing and kneeling, shortening and range of motion of knee and ankle joints. Radiological assessment for union of fracture, alignment of fracture and angulations and position of nail and screws and infection were observed during follow up. A total number of 32 patients were selected but only 27 patients were available for follow up for a period of 6 months. They were grouped into Group A, consisting of 15 patients who took the treatment in the form of closed intramedullary interlocking nailing and Group B, consisting of 12 patients those underwent ORIF with locking compression plating. In both of the groups Motor Vehicle Accident was the main mechanism of trauma. Fracture involving the middle 3rd of the tibia is common in both the groups. During post-operative follow up, four patients in Group A complained anterior knee pain, one patient in Group B had superficial infection, most of the patients had no restriction of movement in the ankle and knee joints and a single patient in Group B showed 1.5cm shortening of the lower limb. Period of hospital stay and fracture union time were less in Group A, which was statistically significant. Both groups showed excellent result with minimum complications. So this study permits to conclude that close IM interlocking nailing and open reduction and internal fixation by locking compression plating is equally effective for the management of close fracture shaft of the tibia.

Background: α-Crystallin acts like a molecular chaperone by interacting with its substrate proteins and thus prevents their aggregation. It also interacts with various kinds of small molecules that affect its structure and function., Scope of Review: In this article we will present a review of work done with respect to the interaction of ATP, peptide generated from lens crystallin and other proteins and some bivalent metal ions with α-crystallin and discuss the role of these interactions on its structure and function and cataract formation. We will also discuss the interaction of some hydrophobic fluorescence probes and surface active agents with α-crystallin., Major Conclusions: Small molecule interaction controls the structure and function of α-crystallin. ATP and Zn+2 stabilize its structure and enhance chaperone function. Therefore the depletion of these small molecules can be detrimental to maintenance of lens transparency. However, the accumulation of small peptides due to protease activity in the lens can also be harmful as the interaction of these peptides with α-crystallin and other crystallin proteins in the lens promotes aggregation and loss of lens transparency. The use of hydrophobic probe has led to a wealth of information regarding the location of substrate binding site and nature of chaperone-substrate interaction. Interaction of surface active agents with α-crystallin has helped us to understand the structural stability and oligomeric dissociation in α-crystallin., General Significance: These interactions are very helpful in understanding the mechanistic details of the structural changes and chaperone function of α-crystallin. This article is part of a Special Issue entitled Crystallin Biochemistry in Health and Disease., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Here, we have investigated the physical and molecular basis of stability of Arabidopsis DNA Pol λ, the sole X family DNA polymerase member in plant genome, under UV-B and salinity stress in connection with the function of the N-terminal BRCT (breast cancer-associated C terminus) domain and Ser-Pro rich region in the regulation of the overall structure of this protein. Tryptophan fluorescence studies, fluorescence quenching and Bis-ANS binding experiments using purified recombinant full length Pol λ and its N-terminal deletion forms have revealed UV-B induced conformational change in BRCT domain deficient Pol λ. On the other hand, the highly conserved C-terminal catalytic core PolX domain maintained its tertiary folds under similar condition. Circular dichroism (CD) and fourier transform infrared (FT-IR) spectral studies have indicated appreciable change in the secondary structural elements in UV-B exposed BRCT domain deficient Pol λ. Increased thermodynamic stability of the C-terminal catalytic core domain suggested destabilizing effect of the N-terminal Ser-Pro rich region on the protein structure. Urea-induced equilibrium unfolding studies have revealed increased stability of Pol λ and its N-terminal deletion mutants at high NaCl concentration. In vivo aggregation studies using transient expression systems in Arabidopsis and tobacco indicated possible aggregation of Pol λ lacking the BRCT domain. Immunoprecipitation assays revealed interaction of Pol λ with the eukaryotic molecular chaperone HSP90, suggesting the possibility of regulation of Pol λ stability by HSP90 in plant cell. Overall, our results have provided one of the first comprehensive information on the biophysical characteristics of Pol λ and indicated the importance of both BRCT and Ser-Pro rich modules in regulating the stability of this protein under genotoxic stress in plants.

Perfluorononanoic acid (PFNA) is a ubiquitous and persistent environmental contaminant. Although its levels in the environment and in humans are lower than those of perfluorooctane sulfonate (PFOS) or perfluorooctanoic acid (PFOA), a steady trend of increases in the general population in recent years has drawn considerable interest and concern. Previous studies with PFOS and PFOA have indicated developmental toxicity in laboratory rodent models. The current study extends the evaluation of these adverse outcomes to PFNA in mice. PFNA was given to timed-pregnant CD-1 mice by oral gavage daily on gestational day 1-17 at 1, 3, 5 or 10mg/kg; controls received water vehicle. Dams given 10mg/kg PFNA could not carry their pregnancy successfully and effects of this dose group were not followed. Similar to PFOS and PFOA, PFNA at 5mg/kg or lower doses produced hepatomegaly in the pregnant dams, but did not affect the number of implantations, fetal viability, or fetal weight. Mouse pups were born alive and postnatal survival in the 1 and 3mg/kg PFNA groups was not different from that in controls. In contrast, although most of the pups were also born alive in the 5mg/kg PFNA group, 80% of these neonates died in the first 10 days of life. The pattern of PFNA-induced neonatal death differed somewhat from those elicited by PFOS or PFOA. A majority of the PFNA-exposed pups survived a few days longer after birth than those exposed to PFOS or PFOA, which typically died within the first 2 days of postnatal life. Surviving neonates exposed to PFNA exhibited dose-dependent delays in eye opening and onset of puberty. In addition, increased liver weight seen in PFNA-exposed offspring persisted into adulthood and was likely related to the persistence of the chemical in the tissue. Evaluation of gene expression in fetal and neonatal livers revealed robust activation of peroxisome proliferator-activated receptor-alpha (PPARα) target genes by PFNA that resembled the responses of PFOA. Our results indicate that developmental toxicity of PFNA in mice is comparable to that of PFOS and PFOA, and that these adverse effects are likely common to perfluoroalkyl acids that persist in the body., (Published by Elsevier Inc.)

Osteoid osteoma is a benign bone tumour usually found in the lower extremities of children and young adults. This tiny bone tumour causes pain out of all proportion to its size and hinders the daily activities. This Quasi-experimental study conducted in the department of Orthopaedic surgery of BSMMU from January 2008 to December 2009. Twenty one patients were included in the study where purposive sampling technique was used on the basis of inclusion and exclusion criteria and all the ethical conditions were fulfilled. Diagnosis was almost obtained by taking history, clinical examination, and relevant investigations. Clinical variables were age, sex, site, pain, swelling, deformity and outcome variables were painless active life, removal of swelling, prevention of deformity, rate of recurrence. After localization of the tumour with the help of C arm, the nidus was excised in a small block of bone. The outcome is categorized by consensus, as clinically successful, only if the patient was free of pain and was taking no medication. The treatment was considered to have failed if a subsequent procedure had been performed to remove tumour. Among 21 cases, 14(66.7%) were male and 7(33.7%) were female. Maximum number of patients 15(71.4%) was between 10 years to 20 years. Most of the patients (76.2%) affected by osteoid osteoma were young students and most of the patients (95.2%) experienced moderate aching pain, usually aggravating at night which was typically relieved by aspirin or other NSAIDs (71.4%). Lower limbs (76.2%) particularly femur and tibia were commonly affected. Out of 21 patients, 19(90.5%) patients have got immediate pain relief or required no medication. In only 2 patients (9.5%), subsequent procedure has been performed to relief pain. So, successful outcome (in 19 out of 21) was significantly (p<0.001) higher in comparison to failed. Surgical excision of the nidus is a simple and easy procedure and does not require extensive resection of bone. If localization is done properly success rate is high and patients can return to normal daily activities.

Early controlled motion programs after flexor tendon repair in zone II of hand are designed to minimize adhesion formation by promoting the excursion of repaired tendons. The flexor tendon surgery especially in zone II is complicated. It is simplest in the newly injured and unscarred digit and the results of correctly rehabilitated primary repair are likely to be the best attainable. We conducted a study including 18 patients with 52 digits involving 80 flexor tendons in zone II to observe and record the result of the primary or delayed primary repair with early active mobilization protocol. Thirteen (72.22%) patients were below 30 years of age. Sixteen cases (88.89%) were sustained injury by sharp instrument either accidentally or by assault. Ring and little finger were involved in 50% instances. The repair was done with the modified Kessler core suture technique with locking epitendinous sutures with a knot inside the repair site, using polypropylene 4-0 and 6-0 sutures. The final assessment was done at 6 months post repair using the Louisville system of Lister et al. 61.54% (n=32) digits were shown excellent result whereas good results were seen in 23% (n=12) digits. Fair was shown 7.69% (n=4) digits and 7.69% (n=4) digits were shown poor results. P value was <0.001 by Z test which is significant. Complications included tendon rupture in 3(5.77%) cases (one thumb, one ring and one little finger) and contracture in 4(7.69%) cases whereas superficial infection and flap necrosis was seen in one (1.92%) case each. The primary or delayed primary repair of cut flexor tendons in zone II using the modified Kessler core suture and epitendinous suture with early active mobilization protocol has been given good result, with minimal complications.

Unicameral bone cyst is a common benign bone tumor and most frequent cause of the pathological fracture in children. We have started a prospective study for that treatment of unicameral bone cyst by using freeze dried radiation sterilized bone allograft impregnated with autogenous bone marrow in the department of Orthopaedics, Bangabandhu Sheikh Mujib Medical University (BSMMU) during May 1999 to April 2012. Aim of this study was to see Freeze dried radiation sterilized bone allograft impregnate with autogenous bone marrow a satisfactory graft material in the treatment of unicameral bone cyst as well as factors such as patients age, sex, cyst size and site of lesion influence on cyst healing. A total 35 patients of unicameral bone cyst were operated. In this study out of 35 patients, male were 22(62.86%) and female were 13(37.14). Male Female ratio 22:13(1.70:1) Age of the patients ranging from 2 years 6 month to 20 years, mean age 12.18 years more common 11 years to 20 years 29(82.86%) patients. Common bones sites involvements are proximal end of Humerus 20(57.14%), proximal end of Femur 7(20 %), proximal end of Tibia 3(8.57%), Calcanium 2(5.71%), proximal end of Ulna 1(2.86%), shaft of Radius 1(2.86%) and Phalanx 1(2.86%). Final clinical outcome of unicameral bone cyst treated by thorough curettage of cavity and tightly filled with freeze dried radiation sterilized bone allograft impregnate with autogenous bone marrow in which healed (success rate) 88.57% (31) and recurrence rate is 11.43% (4). P value is <0.001. Follow up period was 6 month to 11 years. From our study it was realized that freeze dried radiation sterilized bone allograft impregnated with autogenous bone marrow is useful graft material for healing of the lesional area as well as restoring structural integrity for the treatment of unicameral bone cyst.

The insecticidal potential of Galanthus nivalis agglutinin-related lectins against hemipterans has been experimentally proven. However, the basis behind the toxicity of these lectins against hemipterans remains elusive. The present study elucidates the molecular basis behind insecticidal efficacy of Colocasia esculenta tuber agglutinin (CEA) against Bemisia tabaci and Lipaphis erysimi. Confocal microscopic analyses highlighted the binding of 25 kDa stable homodimeric lectin to insect midgut. Ligand blots followed by LC MS/MS analyses identified binding partners of CEA as vacuolar ATP synthase and sarcoplasmic endoplasmic reticulum type Ca(2+) ATPase from B. tabaci, and ATP synthase, heat shock protein 70 and clathrin heavy chain assembly protein from L. erysimi. Internalization of CEA into hemolymph was confirmed by Western blotting. Glycoprotein nature of the receptors was identified through glycospecific staining. Deglycosylation assay indicated the interaction of CEA with its receptors to be probably glycan mediated. Surface plasmon resonance analysis revealed the interaction kinetics between ATP synthase of B. tabaci with CEA. Pathway prediction study based on Drosophila homologs suggested the interaction of CEA with insect receptors that probably led to disruption of cellular processes causing growth retardation and loss of fecundity of target insects. Thus, the present findings strengthen our current understanding of the entomotoxic potentiality of CEA, which will facilitate its future biotechnological applications., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

α-Crystallin is a multimeric eye lens protein having molecular chaperone-like function which is crucial for lens transparency. The stability and unfolding-refolding properties of α-crystallin plays important roles for its function. We undertook a multi probe based fluorescence spectroscopic approach to explore the changes in the various levels of organization of this protein at different urea concentration. Steady state fluorescence studies reveal that at 0.6M urea a compact structural intermediate is formed which has a native-like secondary structure with enhanced surface exposure of hydrophobic groups. At 2.8M urea the tertiary interactions are largely collapsed with partial collapse of secondary and quaternary structure. The surface solvation probed by picosecond time resolved fluorescence of acrylodan labeled α-crystallin revealed dry native-like core of α-crystallin at 0.6M urea compared to enhanced water penetration at 2.8M urea and extensive solvation at 6M urea. Activation energy for the subunit exchange decreased by 22 kJ mol(-1) on changing urea concentration from 0 to 0.6M compared with over 75 kJ mol(-1) on changing urea concentration from 0 to 2.8M. Light scattering and analytical ultracentrifugation techniques were used to determine size and oligomerization of the unfolding intermediates. The data indicated swelling but no oligomer breakdown at 0.6M urea. At 2.8M urea the oligomeric size is considerably reduced and a monomer is produced at 6M urea. The data clearly reveals that structural breakdown of α-crystallin does not follow hierarchical sequence as tertiary structure dissolution takes place before complete oligomeric dissociation., (Copyright © 2013 Wiley Periodicals, Inc.)

Proteins adsorb onto a nanoparticle surface to form a protein-nanoparticle corona which becomes the identity of the nanoparticle in the cellular environment. Conformation of the protein at the interface influences the cellular uptake of the nanoparticle. Hence, interaction of proteins with nanomaterials is of special significance in the field of biotechnology. Adsorption of protein on the nanoparticle surface is a complex process that depends on the dielectric properties and pH of the medium, surface morphology and surface heterogeneity of the nanoparticle, and the quaternary structure of the protein. Thus, interaction of a large multimeric protein with a nanoparticle will be different from that of small oligomeric proteins. In this article we report the conformational and functional properties of a large oligomeric protein αA-Crystallin, a major constituent of the mammalian eye lens, adsorbed onto silver nanoparticle surface. Selective alkylation of the two cysteine residues at the α-Crystallin domain, followed by ITC study showed that these residues play crucial roles in the interaction process. The chaperone function and the refolding capacity of the protein, which is primarily governed by the α-Crystallin domain, are lost to a significant extent when adsorbed onto AgNP surface. The protein in the interface also shows loss of oligomerization that is linked to the biological activity of the protein. Nonetheless, the protein at bio-nano interface shows resistance to urea unfolding process as compared to protein in the solution phase. This might be due to the coordination of AgNP with two cysteine residues of β8 and β9 region of the α-Crystallin domain that imparts extra stability. The compactness in the structure of the adsorbed protein reduces the dynamics of the subunit exchange, which was confirmed by the FRET study. The secondary structure of αA-Crystallin bound to AgNP at substoichiometric ratio remained native-like.

Glutamyl-queuosine-tRNA(Asp) synthetase (Glu-Q-RS) and glutamyl-tRNA synthetase (GluRS), differ widely by their function although they share close structural resemblance within their catalytic core of GluRS. In particular both Escherichia coli GluRS and Glu-Q-RS contain a single zinc-binding site in their putative tRNA acceptor stem-binding domain. It has been shown that the zinc is crucial for correct positioning of the tRNA(Glu) acceptor-end in the active site of E. coli GluRS. To address the role of zinc ion in Glu-Q-RS, the C101S/C103S Glu-Q-RS variant is constructed. Energy dispersive X-ray fluorescence show that the zinc ion still remained coordinated but the variant became structurally labile and acquired aggregation capacity. The extent of aggregation of the protein is significantly decreased in presence of the small substrates and more particularly by adenosine triphosphate. Addition of zinc increased significantly the solubility of the variant. The aminoacylation assay reveals a decrease in activity of the variant even after addition of zinc as compared to the wild-type, although the secondary structure of the protein is not altered as shown by the Fourier transform infrared spectroscopy study.

Silver nanoparticles are finding increasing applications in biological systems, for example as antimicrobial agents and potential candidates for control drug release systems. In all such applications, silver nanoparticles interact with proteins and other biomolecules. Hence, the study of such interactions is of considerable importance. While BSA has been extensively used as a model protein for the study of interaction with the silver nanoparticles, studies using other proteins are rather limited. The interaction of silver nanoparticles with light leads to collective oscillation of the conducting electrons giving rise to surface plasmon resonance (SPR). Here, we have studied the protein concentration dependence of the SPR band profiles for a number of proteins. We found that for all the proteins, with increase in concentration, the SPR band intensity initially decreased, reaching minima and then increased again leading to a characteristic "dip and rise" pattern. Minimum point of the pattern appeared to be related to the isoelectric point of the proteins. Detailed dynamic light scattering and transmission electron microscopy studies revealed that the consistency of SPR profile was dependent on the average particle size and state of association of the silver nanoparticles with the change in the protein concentration. Fluorescence spectroscopic studies showed the binding constants of the proteins with the silver nanoparticles were in the nano molar range with more than one nanoparticle binding to protein molecule. Structural studies demonstrate that protein retains its native-like structure on the nanoparticle surface unless the molar ratio of silver nanoparticles to protein exceeds 10. Our study reveals that nature of the protein concentration dependent profile of SPR signal is a general phenomena and mostly independent of the size and structure of the proteins., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A non-toxic, nine residue peptide, NIVNVSLVK is shown to interfere with insulin fibrillation by various biophysical methods. Insulin undergoes conformational changes under certain stress conditions leading to amyloid fibrils. Fibrillation of insulin poses a problem in its long-term storage, reducing its efficacy in treating type II diabetes. The dissociation of insulin oligomer to monomer is the key step for the onset of fibrillation. The time course of insulin fibrillation at 62°C using Thioflavin T fluorescence shows an increase in the lag time from 120 min without peptide to 236 min with peptide. Transmission electron micrographs show branched insulin fibrils in its absence and less inter-fibril association in its presence. Upon incubation at 62°C and pH 2.6, insulin lost some α-helical structure as seen by Fourier transformed infra-red spectroscopy (FT-IR), but if the peptide is added, secondary structure is almost fully maintained for 3 h, though lost partially at 4 h. FT-IR spectroscopy also shows that insulin forms the cross beta structure indicative of fibrils beyond 2 h, but in the presence of the peptide, α-helix retention is seen till 4 h. Both size exclusion chromatography and dynamic light scattering show that insulin primarily exists as trimer, whose conversion to a monomer is resisted by the peptide. Saturation transfer difference nuclear magnetic resonance confirms that the hydrophobic residues in the peptide are in close contact with an insulin hydrophobic groove. Molecular dynamics simulations in conjunction with principal component analyses reveal how the peptide interrupts insulin fibrillation. In vitro hemolytic activity of the peptide showed insignificant cytotoxicity against HT1080 cells. The insulin aggregation is probed due to the inter play of two key residues, Phe(B24) and Tyr(B26) monitored from molecular dynamics simulations studies. Further new peptide based leads may be developed from this nine residue peptide.

While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) detected in the environment. Using a transient transfection assay developed in COS-1 cells, our group has previously evaluated a variety of PFAAs for activity associated with activation of peroxisome proliferator-activated receptor alpha (PPARα). Here we use primary heptatocytes to further assess the biological activity of a similar group of PFAAs using custom designed Taqman Low Density Arrays. Primary mouse and human hepatoyctes were cultured for 48h in the presence of varying concentrations of 12 different PFAAs or Wy14,643, a known activator of PPARα. Total RNA was collected and the expression of 48 mouse or human genes evaluated. Gene selection was based on either in-house liver microarray data (mouse) or published data using primary hepatocytes (human). Gene expression in primary mouse hepatocytes was more restricted than expected. Genes typically regulated in whole tissue by PPARα agonists were not altered in mouse cells including Acox1, Me1, Acaa1a, Hmgcs1, and Slc27a1. Cyp2b10, a gene regulated by the constitutive androstane receptor and a transcript normally up-regulated by in vivo exposure to PFAAs, was also unchanged in cultured mouse hepatocytes. Cyp4a14, Ehhadh, Pdk4, Cpt1b, and Fabp1 were regulated as expected in mouse cells. A larger group of genes were differentially expressed in human primary hepatocytes, however, little consistency was observed across compounds with respect to which genes produced a significant dose response making the determination of relative biological activity difficult. This likely reflects weaker activation of PPARα in human versus rodent cells as well as variation among individual cell donors. Unlike mouse cells, CYP2B6 was up-regulated in human hepatocytes by a number of PFAAs as was PPARδ. Rankings were conducted on the limited dataset. In mouse hepatocytes, the pattern was similar to that previously observed in the COS-1 reporter cell assay. With the exception of PFHxA, longer chain PFAA carboxylates were the most active. The pattern was similar in human hepatocytes, although PFDA and PFOS showed higher activity than previously observed while PFOA showed somewhat less activity. These data reflect inherent challenges in using primary hepatocytes to predict toxicological response., (Published by Elsevier Ireland Ltd.)

DNA polymerase λ (Pol λ) is the sole member of family X DNA polymerase in plants and plays a crucial role in nuclear DNA damage repair. Here, we report the transcriptional up-regulation of Arabidopsis (Arabidopsis thaliana) AtPolλ in response to abiotic and genotoxic stress, including salinity and the DNA cross-linking agent mitomycin C (MMC). The increased sensitivity of atpolλ knockout mutants toward high salinity and MMC treatments, with higher levels of accumulation of double strand breaks (DSBs) than wild-type plants and delayed repair of DSBs, has suggested the requirement of Pol λ in DSB repair in plants. AtPolλ overexpression moderately complemented the deficiency of DSB repair capacity in atpolλ mutants. Transcriptional up-regulation of major nonhomologous end joining (NHEJ) pathway genes KU80, X-RAY CROSS COMPLEMENTATION PROTEIN4 (XRCC4), and DNA Ligase4 (Lig4) along with AtPolλ in Arabidopsis seedlings, and the increased sensitivity of atpolλ-2/atxrcc4 and atpolλ-2/atlig4 double mutants toward high salinity and MMC treatments, indicated the involvement of NHEJ-mediated repair of salinity- and MMC-induced DSBs. The suppressed expression of NHEJ genes in atpolλ mutants suggested complex transcriptional regulation of NHEJ genes. Pol λ interacted directly with XRCC4 and Lig4 via its N-terminal breast cancer-associated C terminus (BRCT) domain in a yeast two-hybrid system, while increased sensitivity of BRCT-deficient Pol λ-expressing transgenic atpolλ-2 mutants toward genotoxins indicated the importance of the BRCT domain of AtPolλ in mediating the interactions for processing DSBs. Our findings provide evidence for the direct involvement of DNA Pol λ in the repair of DSBs in a plant genome.

α-Crystallin, a member of the small heat shock protein family is the major protein of mammalian eye lens and is a molecular chaperone. As there is no protein turn over in the lens, stability of α-crystallin is one of the most crucial factors for its survival and function. We previously reported that the molecular chaperone-like activity and stability of α-crystallin dramatically increased in the presence of Zn(2+) (Biochemistry, 2008). We also reported that each subunit of α-crystallin could bind multiple zinc ions through inter-subunit bridging giving rise to enhanced stability (Biopolymers, 2011). The amino acid residues involved in zinc binding were not known. Since cysteine residues were not responsible for binding to Zn(2+), we tried to identify the histidine residues bound to zinc ions. We modified recombinant αA- and αB-crystallin with diethylpyrocarbonate (DEPC) a histidine modifying reagent, in presence and absence of Zn(2+) followed by tryptic digestion. The residues modified by DEPC were identified through peptide mass matching by MALDI mass spectrometry. We have clearly identified H79, H107 and H115 of αA-crystallin and H104, H111 and H119 of αB-crystallin as the Zn(2+) binding residues. The significance of the histidine rich sequence region of α-crystallin for its stability is discussed.

Background: In 2002 and 2009, two consensus statements-one from a symposium in Canada and one from England-were issued that recommended that the first-choice standard of care for an edentulous mandible should be the two implant-retained mandibular overdenture (IRMOD). The authors conducted a survey to determine if, in 2011, U.S. academic prosthodontic experts' opinions were aligned with those in the two consensus statements., Methods: The authors administered a Delphi method survey to an expert panel of 16 nationally representative academic prosthodontists to determine if there is consensus on the first-choice standard of care for an edentulous mandible between the IRMOD and a conventional mandibular complete denture (CD). Consensus agreement was defined as a 70 percent agreement level among the panelists., Results: The panel attained consensus favoring the IRMOD for nine of the 10 parameters assessed-retention, stability, speech, masticatory efficiency, comfort while eating soft foods and hard foods, confidence in intimate situations, satisfaction and self-esteem. The exception was esthetics for which only a majority (51-69 percent) favored the IRMOD., Conclusions: The panelists reached consensus that they would recommend an IRMOD instead of a CD as the first-choice standard of care for patients who are healthy or have mild systemic disease, but not for patients with severe systemic disease., Clinical Implications: Surveyed academic prosthodontists recommend an IRMOD as the first choice standard of care when restoring an edentulous mandible of a healthy patient or a patient with mild systemic disease.

PPARs regulate metabolism and can be activated by environmental contaminants such as perfluorooctanoic acid (PFOA). PFOA induces neonatal mortality, developmental delay, and growth deficits in mice. Studies in genetically altered mice showed that PPARα is required for PFOA-induced developmental toxicity. In this study, pregnant CD-1 mice were dosed orally from GD1 to 17 with water or 5mg PFOA/kg to examine PPARα, PPARβ, and PPARγ expression and profile the effects of PFOA on PPAR-regulated genes. Prenatal and postnatal liver, heart, adrenal, kidney, intestine, stomach, lung, spleen, and thymus were collected at various developmental ages. RNA and protein were examined using qPCR and Western blot analysis. PPAR expression varied with age in all tissues, and in liver PPARα and PPARγ expression correlated with nutritional changes as the pups matured. As early as GD14, PFOA affected expression of genes involved in lipid and glucose homeostatic control. The metabolic disruption produced by PFOA may contribute to poor postnatal survival and persistent weight deficits of CD-1 mouse neonates., (Published by Elsevier Inc.)

Structure and dynamics of acrylodan labeled αA-crystallin tetramer formed in the presence of a bile salt (sodium deoxycholate, NaDC) has been studied using fluorescence correlation spectroscopy (FCS) and femtosecond up-conversion techniques. Using FCS it is shown that, the diffusion constant (D(t)) of the αA-crystallin oligomer (mass ~800 kDa) increases from ~35 μm(2) s(-1) to ~68 μm(2) s(-1). This corresponds to a decrease in hydrodynamic radius (r(h)) from ~6.9 nm to ~3.3 nm. This corresponds to about 10-fold decrease in molecular mass to ~80 kDa and suggests formation of a tetramer (since mass of αA-crystallin monomer is ~20 kDa). The steady state emission maximum and average solvation time (<τ(s)>) of acrylodan labeled at cysteine 131 position of αA-crystallin is markedly affected on addition of NaDC, while the tryptophan (trp-9) becomes more exposed. This suggests that NaDC binds near the cys-131 and makes the terminal region of αA-crystallin exposed. This may explain the enhanced auto-phosphorylation activity of αA-crystallin near the terminus of the 173 amino acid protein (e.g., at the threonine 13, serine 45, or serine 169 and 172) and suggests that phosphorylation at ser-122 (close to cys-131) is relatively less important.

Many proteins form ordered irreversible structural aggregates called amyloid fibrils, which are associated with numerous neurodegenerative diseases. Insulin, a largely α-helical protein associated with type II diabetes, self-assembles to form amyloid fibrils in vitro. Insulin fibrillation goes through a number of intermediate phases that includes a soluble oligomeric phase believed to be the most toxic phase. Small molecules may play a very important role in modulating the fibrillation pathways. It is possible to induce and stabilize helix structures in proteins by a fluorinated alcohol 2,2,2-trifluoro ethanol (TFE). Since fibrillation process of many proteins is associated with conversion of α-helical structures into β-sheet configuration, we thought it would be interesting to study the effect of TFE on the fibrillation of insulin. In absence of TFE, soluble protofibrillar oligomeric intermediates formed directly from the insulin trimer. The protofibrillar aggregates transformed into mature fibrils over time. We demonstrated that although TFE did not prevent the appearance of matured amyloid fibrils, it prevented the appearance of soluble aggregates of insulin. TFE converted the insulin trimer into monomers and fibril formation proceeded from the monomeric state in a cooperative way avoiding the soluble oligomeric phase. At 25% TFE, distinct morphological changes resulting in more discrete fibrils were visible. The effect of the small molecule TFE on the avoidance of the formation soluble oligomeric state during fibrillation may have considerable implications in reducing cellular toxicity., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Genetic and molecular analyses mainly in Arabidopsis and in some other plants have demonstrated involvement of light signaling in cell cycle regulation. In this report, we show light-mediated activation of the promoter of AtPolλ gene, a homolog of mammalian DNA polymerase λ in Arabidopsis thaliana and an important component of DNA damage repair/recombination machinery in plants. Analyses of the light-mediated promoter activity using various deletion versions of AtPolλ promoter in transformed Arabidopsis and tobacco (Nicotiana tabaccum) plants indicate that a 130-bp promoter region between -536 and -408 of AtPolλ promoter is essential for light-induced regulation of AtPolλ expression. DNA-protein interaction studies reveal that an ATCT-motif and AE-box light-responsive elements in the light-regulated promoter region confer light responsiveness of AtPolλ promoter. DNA-binding analysis has identified a 63-kDa trans-acting protein factor which showed specific binding to ATCT-motif, while another trans-acting factor of ~52 kDa was found to bind specifically to both ATCT and AE-box sequences. The 52-kDa protein has been identified as B3-domain transcription factor by MALDI-TOF/MS analysis. Overall, our results provide novel information on the role of light signaling in regulation of expression of an important component of DNA repair machinery in plants.

Epidermoid cyst of the neck or auricular area are relatively more common than that of the oral cavity. In most cases about 80% they remain asymptomatic. But in about 20% cases it becomes painful because of secondary infection seeking treatment. Here we present a case report of biopsy proved Epidermoid cyst with life threatening infection.

Perfluorononanoic acid (PFNA) is a fluorinated organic chemical found at low levels in the environment, but is detectable in humans and wildlife. The present study compared the pharmacokinetic properties of PFNA in two laboratory rodent species. Male and female Sprague-Dawley rats were given a single dose of PFNA by oral gavage at 1, 3, or 10mg/kg, and blood was collected from the tail vein at 1, 2, 3, 4, 7, 16, 21, 28, 35, 42 and 50 days after treatment. In addition, livers and kidneys were collected for PFNA analysis at the terminal time point. CD-1 mice were given a single oral dose of PFNA of 1 or 10mg/kg, and 4 males and 4 females were killed at similar time intervals; trunk blood, liver and kidney were collected. Serum and tissue concentrations of PFNA were determined by LC-MS/MS. Serum elimination of PFNA is by and large linear with exposure doses in the rat; however, like PFOA, a major sex difference in the rate of elimination is observed, with an estimated half-life of 30.6 days for males and 1.4 days for females. PFNA is stored preferentially in the liver but not in the kidneys. In the mouse, the rates of PFNA serum elimination are non-linear with exposure dose and are slightly faster in females than males, with terminal estimated serum half-life of 25.8-68.4 days and 34.3-68.9 days, respectively. PFNA is also stored preferentially in the mouse liver but not in the kidneys. Hepatic uptake appears to be more efficient and storage capacity greater in male mice than in females. These data suggest that (1) PFNA is more persistent in the mouse than in the rat; (2) there is a major sex difference in the serum elimination of PFNA in the rat, but much less so in the mouse; and (3) there is a significantly higher hepatic accumulation of PFNA in male mice than in females., (Published by Elsevier Ireland Ltd.)

α-Crystallin, the major protein of mammalian eye lens, is a member of the small heat shock protein family and is a molecular chaperone. We previously reported that its molecular chaperone function as well as stability increased in presence of Zn+². Despite the effect of Zn+² on the structure and function of α-crystallin, evidence for direct interaction between them remained elusive. We now present the MALDI mass spectrometric data that shows direct evidence of Zn+² binding to recombinant αA- and αB-crystallin. The binding stoichiometry was over three Zn+² per subunit of α-crystallin at zinc/protein molar ratio of 20. Observation of multiple Zn+² binding is consistent with the large increase in thermodynamic stability. Sequence-based analysis of αA- and αB-crystallin predicted both proteins to be nonzinc binding proteins. Our dynamic light scattering data shows that Zn+² stabilizes the oligomeric structure of α-crystallin by bridging neighboring subunits in multiple centers. Despite the low affinity binding, the intersubunit bridging by multiple Zn+² makes the oligomer so stable that oligomer breakdown does not occur even at 6M urea. The subunit bridging has been supported by our FRET data that showed absence of subunit exchange in presence of zinc. MALDI data also showed that the interaction of α-crystallin with Zn+² is quite different from other bivalent metal ions. Bound Zn+² could be easily removed by dialysis of the complex. The relevance of such weak interaction on the stability of the oligomeric structure of α-crystallin and its function in the eye lens has been discussed., (© 2010 Wiley Periodicals, Inc.)