Search

The physical properties of perovskite-type materials are sensitive to their chemical composition and crystallographic structure, which makes them highly versatile for various advanced technological applications. In this theoretical study, density functional theory (DFT) is employed to investigate the electronic properties of the perovskite-like material CaTiO3, focusing on the substitution of Ti4+ with the magnetic transition metal Cr4+. The results reveal a systematic increase in the effective magnetic moment and a gradual decrease in the bandgap with increasing Cr4+ content in the CaTi1−xCrxO3 system (x = 0.0, 0.25, 0.5, 0.75, 1.0). The interactions between electronic orbitals associated with Ti-O-Cr inter-octahedral bonds modify the magnetic response of the material, leading to hybridizations between valence and conduction states that alter its semiconductor character. This tunability in electronic and magnetic properties underscores the potential of these materials for applications in spintronics. This study offers novel insights into the design of new magnetic semiconductor materials with tailored functionalities, contributing to the development of next-generation spintronic devices. [ABSTRACT FROM AUTHOR]

Copyright of Prosperitas is the property of Budapest Business School / Budapesti Gazdasagi Egyetem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tooth agenesis is the most common anomaly of craniofacial development. The purpose of this report is to present a brief review of literature about tooth agenesis, which includes: terminology, etiology, prevalence, associated syndromes and dental anomalies. Two clinical cases are presented. In Colombia there are no studies which allow us to determine the genetic causes of this anomaly, more research is needed in this area in order to clarify its etiology.

Financial pyramids commonly collapse. The literature has employed various mathematical methods to explain that behavior. This article uses a different methodology to explain their rise and crisis. The methodology integrates two disciplines: systems dynamics and an epidemic analysis method called SIR. The article's main objective is to develop a system dynamics model to determine the threshold of a pyramid scheme. The conclusion is that the decrease in potential customers and, therefore, the decrease in new customers entering the business is the primary explanation for the collapse of these pyramids. [ABSTRACT FROM AUTHOR]

Infants with biallelic IL7R loss-of-function variants have severe combined immune deficiency (SCID) characterized by the absence of autologous T lymphocytes, but normal counts of circulating B and NK cells (T-B+NK+ SCID). We report 6 adults (aged 22 to 59 years) from 4 kindreds and 3 ancestries (Colombian, Israeli Arab, Japanese) carrying homozygous IL7 loss-of-function variants resulting in combined immunodeficiency (CID). Deep immunophenotyping revealed relatively normal counts and/or proportions of myeloid, B, NK, and innate lymphoid cells. By contrast, the patients had profound T cell lymphopenia, with low proportions of innate-like adaptive mucosal-associated invariant T and invariant NK T cells. They also had low blood counts of T cell receptor (TCR) excision circles, recent thymic emigrant T cells and naive CD4+ T cells, and low overall TCR repertoire diversity, collectively indicating impaired thymic output. The proportions of effector memory CD4+ and CD8+ T cells were high, indicating IL-7-independent homeostatic T cell proliferation in the periphery. Intriguingly, the proportions of other T cell subsets, including TCRγδ+ T cells and some TCRαβ+ T cell subsets (including Th1, Tfh, and Treg) were little affected. Peripheral CD4+ T cells displayed poor proliferation, but normal cytokine production upon stimulation with mitogens in vitro. Thus, inherited IL-7 deficiency impairs T cell development less severely and in a more subset-specific manner than IL-7R deficiency. These findings suggest that another IL-7R-binding cytokine, possibly thymic stromal lymphopoietin, governs an IL-7-independent pathway of human T cell development.

Introduction: Von Willebrand factor (VWF) plays a pathophysiological role in hemostatic disorders. Partial inhibition of the VWF gene through small interfering RNA (siRNA)-mediated allele-selective silencing could be a promising therapeutic strategy. For von Willebrand disease, allele-selectively inhibiting dominant-negative VWF-alleles might ameliorate the phenotype. For thrombotic disorders, partial VWF reduction can lower thrombotic risk, while avoiding bleeding. Previously, we demonstrated the feasibility of Vwf-silencing in homozygous C57BL/6J (B6) or 129S1/SvImJ (129S) mice. The present study investigated allele-selective Vwf-silencing in a complex heterozygous setting of crossed B6 and 129S mice and its subsequent hemostatic impact., Materials and Methods: Heterozygous B6.129S mice were treated with siRNAs targeting Vwf expressed from either B6- (siVwf.B6) or 129S-alleles (siVwf.129S). Plasma VWF and lung Vwf mRNA were determined. siVwf.B6-treated B6.129S mice were subjected to ferric chloride-induced mesenteric vessel thrombosis and tail-bleeding., Results: In B6.129S mice, siVwf.B6 reduced Vwf mRNA of the targeted B6-allele by 72% vs. only 12% of the non-targeted 129S-allele (41% total mRNA reduction), lowering plasma VWF by 46%. Oppositely, siVwf.129S reduced Vwf mRNA by 45%, now selectively inhibiting the 129S-allele over the B6-allele (58% vs. 9%), decreasing plasma VWF by 43%. The allele-selective VWF reduction by siVwf.B6 coincided with decreased thrombus formation in mesenteric arterioles, without prolonging tail-bleeding times., Conclusions: This study demonstrates the feasibility of allele-selective Vwf-silencing in a heterozygous setting, achieving a controlled close to 50% reduction of plasma VWF. The observed thromboprotection and absence of prolonged bleeding times underline the potential of allele-selective Vwf-silencing as a therapeutic strategy in hemostatic disorders., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: YKJ and JCJE – Dutch Thrombosis Foundation (TSN) grant #2018-01. NAL and JCJE – Netherlands Organization for Scientific Research (NWO) NWO-AES grant #18712. SNJL and JCJE – Netherlands Organization for Scientific Research (NWO) NWA-ORC grant #1160.18.038. JCJE – CSL Behring research funding. RJD, ESE, JED, BJMvV, CVD declare they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

An imbalance in von Willebrand factor (VWF) may either lead to bleeding (von Willebrand disease, VWD) or thrombosis. Both disorders have shortcomings in the currently available treatments. VWF itself could be a potential therapeutic target because of its role in both bleeding and thrombosis. Inhibiting VWF gene expression through allele-selective silencing of VWF with small interfering RNAs (siRNAs) could be a personalized approach to specifically inhibit mutant VWF in VWD or to normalize increased VWF levels in thrombotic disorders without complete VWF knockdown. Therefore, we investigated a method to allele-selectively silence the VWF gene in mice as a therapeutic strategy. Fourteen candidate siRNAs targeting murine Vwf of either the C57BL/6J (B6) or the 129S1/SvImJ (129S) strain were tested in vitro in cells expressing B6- and 129S-Vwf for inhibitory effect and allele-selective potential. Together with a nonselective siVwf, 2 lead candidate siRNAs, siVwf.B6 and siVwf.129S, were further tested in vivo in B6 and 129S mice. Efficient endothelial siRNA delivery was achieved by siRNA encapsulation into 7C1 oligomeric lipid nanoparticles. Treatment with the nonselective siVwf resulted in dose-dependent inhibition of up to 80% of both lung messenger RNA and plasma VWF protein in both mouse strains. In contrast, the allele-selective siVwf.B6 and siVwf.129S were shown to be effective in and selective solely for their corresponding mouse strain. To conclude, we showed efficient endothelial delivery of siRNAs that are highly effective in allele-selective inhibition of Vwf in mice, which constitutes an in vivo proof of principle of allele-selective VWF silencing as a therapeutic approach., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Silicon nitride (SiN) coatings may reduce unwanted release of metal ions from metallic implants. However, as SiN slowly dissolves in aqueous solutions, additives that reduce this dissolution rate would likely increase the lifetime and functionality of implants. Adding iron (Fe) and carbon (C) permits tuning of the SiN coatings' mechanical properties, but their effect on SiN dissolution rates, and their capacity to reduce metal ion release from metallic implant substrates, have yet to be investigated. Such coatings have recently been proposed for use in spinal implants; therefore, it is relevant to assess their impact on the viability of cells expected at the implant site, such as microglia, the resident macrophages of the central nervous system (CNS). To study the effects of Fe and C on the dissolution rate of SiN coatings, compositional gradients of Si, Fe and C in combination with N were generated by physical vapor deposition onto CoCrMo discs. Differences in composition did not affect the surface roughness or the release of Si, Fe or Co ions (the latter from the CoCrMo substrate). Adding Fe and C reduced ion release compared to a SiN reference coating, which was attributed to altered reactivity due to an increase in the fraction of stabilizing Si-C or Fe-C bonds. Extracts from the SiN coatings containing Fe and C were compatible with microglial viability in 2D cultures and 3D collagen hydrogels, to a similar degree as CoCrMo and SiN coated CoCrMo reference extracts. As Fe and C reduced the dissolution rate of SiN-coatings and did not compromise microglial viability, the capacity of these additives to extend the lifetime and functionality of SiN-coated metallic implants warrants further investigation.

Background: Hereditary actin-related protein 2/3 complex subunit 1B deficiency is characterized clinically by ear, skin, and lung infections, bleeding, eczema, food allergy, asthma, skin vasculitis, colitis, arthritis, short stature, and lymphadenopathy., Objective: We aimed to describe the clinical, laboratory, and genetic features of six patients from four Mexican families., Methods: We performed exome sequencing in patients of four families with suspected actinopathy, collected their data from medical records, and reviewed the literature for reports of other patients with actin-related protein 2/3 complex subunit 1B deficiency., Results: Six patients from four families were included. All had recurrent infections, mainly bacterial pneumonia, and cellulitis. A total of 67% had eczema whereas 50% had food allergies, failure to thrive, hepatomegaly, and bleeding. Eosinophilia was found in all; 84% had thrombocytopenia, 67% had abnormal-size platelets and anemia. Serum levels of IgG, IgA, and IgE were highly increased in most; IgM was normal or low. T cells were decreased in 67% of patients, whereas B and NK cells were increased in half of patients. Two of the four probands had compound heterozygous variants. One patient was successfully transplanted. We identified 28 other patients whose most prevalent features were eczema, recurrent infections, failure to thrive, bleeding, diarrhea, allergies, vasculitis, eosinophilia, platelet abnormalities, high IgE/IgA, low T cells, and high B cells., Conclusion: Actin-related protein 2/3 complex subunit 1B deficiency has a variable and heterogeneous clinical spectrum, expanded by these cases to include keloid scars and Epstein-Barr virus chronic hepatitis. A novel deletion in exon 8 was shared by three unrelated families and might be the result of a founder effect., (Copyright © 2023 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Lipid nanoparticles (LNPs) have delivered RNA to hepatocytes in patients, underscoring the potential impact of nonliver delivery. Scientists can shift LNP tropism to the lung by adding cationic helper lipids; however, the biological response to these LNPs remains understudied. To evaluate the hypothesis that charged LNPs lead to differential cellular responses, we quantified how 137 LNPs delivered mRNA to 19 cell types in vivo . Consistent with previous studies, we observed helper lipid-dependent tropism. After identifying and individually characterizing three LNPs that targeted different tissues, we studied the in vivo transcriptomic response to these using single-cell RNA sequencing. Out of 835 potential pathways, 27 were upregulated in the lung, and of these 27, 19 were related to either RNA or protein metabolism. These data suggest that endogenous cellular RNA and protein machinery affects mRNA delivery to the lung in vivo .

Cells that were previously described as homogeneous are composed of subsets with distinct transcriptional states. However, it remains unclear whether this cell heterogeneity influences the efficiency with which lipid nanoparticles (LNPs) deliver messenger RNA therapies in vivo. To test the hypothesis that cell heterogeneity influences LNP-mediated mRNA delivery, we report here a new multiomic nanoparticle delivery system called single-cell nanoparticle targeting-sequencing (SENT-seq). SENT-seq quantifies how dozens of LNPs deliver DNA barcodes and mRNA into cells, the subsequent protein production and the transcriptome, with single-cell resolution. Using SENT-seq, we have identified cell subtypes that exhibit particularly high or low LNP uptake as well as genes associated with those subtypes. The data suggest that cell subsets have distinct responses to LNPs that may affect mRNA therapies., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Ceramic coatings have been widely investigated as a means to reduce wear and metallic ion release from joint implants. Silicon nitride-based coatings have been a topic of interest specifically due to their solubility in aqueous solutions. This could imply a reduced adverse immune response since the generated debris would dissolve. However, there are concerns regarding the dissolution rate and adhesion of these silicon nitride-based coatings. This study attempts to address the concern of dissolution rate as well as coating adhesion of silicon nitride coatings. We hypothesized that alloying with chromium and niobium would affect the adhesion, dissolution rate, and the resulting ion release and cell response to the coatings. A combinatorial approach was used to deposit sputtered coatings with compositional gradients both with and without a CrN interlayer. Compositional gradients were achieved for all the investigated elements: Si (38.6-46.9 at%), Nb (2.2-4.6 at%) and Cr (1.9-6.0 at%). However, while the presence of an interlayer reduced the delamination during adhesion testing, the differences in composition in the top coating did not affect the adhesion. Nor did the top coating's composition affect the surface roughness or the coatings' inherent mechanical properties (elastic modulus and hardness). All coating compositions were associated with a low Co release from the underlying metal and points with a higher Cr content (4.3-6.0 at%) gave an overall lower release of Si, Cr and Nb ions, possibly due to the formation of a stable oxide, which reduced the dissolution rate of the coating. Optimum chromium contents were furthermore found to give an enhanced in vitro fibroblast cell viability. In conclusion, the results indicate a possibility to tailor the ion release rate, which lends promise to further investigations such as tribocorrosive tests towards a future biomedical application.

Introduction: Common variable immunodeficiency (CVID) is the most prevalent symptomatic humoral deficiency; however, its heterogeneous presentation makes the diagnosis difficult. The present study is aimed to verify the CVID diagnostic criteria as established by the European Society for Immunodeficiencies in 42 CVID patients from our outpatient clinic., Methods: Information was collected from their medical records and when needed, lymphocyte subpopulations in peripheral blood (PB) were performed by flow cytometry., Results: All the patients fulfilled the clinical working definition for CVID and showed decreased serum IgG and IgA at diagnosis. Over two-thirds of the patients had decreased memory B cell percentages. However, the remaining patients exhibited other quantitative B cell defects in PB. Evaluation of vaccination responses was only found in 13 records and 69% were not responsive. None of the patients were subjected to vaccination studies to both, T-cell dependent and independent antigens. The two required tests to evaluate T cell responses were performed in 84.2% of the patients and reported normal. Without the support of third-party payers, only 34.2% of our patients would have completed the required evaluations., Conclusions: Further efforts are needed to speed up CVID diagnosis in low-resourced settings, increasing the availability of the required resources and optimizing the healthcare supply chain., Competing Interests: The authors declare no potential conflicts of interest with respect to research, authorship, and/or publication of this article.

Scleral photocrosslinking is increasingly investigated for treatment of myopia and glaucoma. In this study a computational model was developed to predict crosslinking efficiency of visible/near infrared photosensitizers in the sclera. Photocrosslinking was validated against riboflavin corneal crosslinking experimental studies and subsequently modeled for the sensitizer, methylene blue, administered by retrobulbar injection to the posterior sclera and irradiated with a transpupillary light beam. Optimal ranges were determined for treatment parameters including light intensity, methylene blue concentration, injection volume, and inspired oxygen concentration. Additionally, sensitivity of crosslinking to various parameters was quantified. The most sensitive parameters were oxygen concentration in the injection solution, scleral thickness, and injection reservoir thickness (i.e., injection volume)., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Purpose: Scleral stiffening may protect against glaucomatous retinal ganglion cell (RGC) loss or dysfunction associated with ocular hypertension. Here, we assess the potential neuroprotective effects of two treatments designed to stiffen either the entire posterior sclera or only the sclera adjacent to the peripapillary sclera in an experimental model of glaucoma., Methods: Rat sclerae were stiffened in vivo using either genipin (crosslinking the entire posterior sclera) or a regionally selective photosensitizer, methylene blue (stiffening only the juxtaperipapillary region surrounding the optic nerve). Ocular hypertension was induced using magnetic microbeads delivered to the anterior chamber. Morphological and functional outcomes, including optic nerve axon count and appearance, retinal thickness measured by optical coherence tomography, optomotor response, and electroretinography traces, were assessed., Results: Both local (juxtaperipapillary) and global (whole posterior) scleral stiffening treatments were successful at increasing scleral stiffness, but neither provided demonstrable neuroprotection in hypertensive eyes as assessed by RGC axon counts and appearance, optomotor response, or electroretinography. There was a weak indication that scleral crosslinking protected against retinal thinning as assessed by optical coherence tomography., Conclusions: Scleral stiffening was not demonstrated to be neuroprotective in ocular hypertensive rats. We hypothesize that the absence of benefit may in part be due to RGC loss associated with the scleral stiffening agents themselves (mild in the case of genipin, and moderate in the case of methylene blue), negating any potential benefit of scleral stiffening., Translational Relevance: The development of scleral stiffening as a neuroprotective treatment will require the identification of better tolerated stiffening protocols and further preclinical testing.

Introduction: Patients with inborn errors of immunity (IEI) have a compromised or inappropriate immune response. Although they might be considered a high-risk group for severe SARS-CoV-2 infection, the reported impact of COVID-19 in these patients has been reassuring, while the differential susceptibility of distinct types of IEI remains unclear., Objective: We aimed to describe the findings and outcomes of our known patients with IEI who were diagnosed with COVID-19., Methods: In a retrospective study from March 2020 to February 2021, four centers in Mexico collected clinical, laboratory, and genetic data from pediatric and adult patients with known diagnoses of IEI who presented with COVID-19, based on compatible symptoms and positive SARS-CoV-2 testing or known household exposure., Results: We report 31 patients with known IEI from Mexico who presented with SARS-CoV-2 infection. Seventy-four percent were male, 52% were pediatric, and 81% survived. Their ages ranged from 5 months to 56 years, with a median of 17 years. Sixty-five percent had predominant antibody deficiencies, 48% were hospitalized, and 26% required ICU. Pediatric patients had a higher hospital admission rate than adults. Inpatient mortality was 40%, and ICU mortality rate was 63%. Forty-eight percent developed pneumonia, while 36% had evidence of hyperinflammation (4 adults and 7 children). Predominant laboratory features were lymphopenia and thrombocytopenia, seen in 70 and 44% of patients, respectively. The serum D-dimer median value was 2.6 (0.5-20.6) μg/mL, and the median highest ferritin value was 1015 (32-10,303) ng/mL. Intravenous immunoglobulin was used in 80% of patients. Other treatments included macrolides (39%) and corticosteroids (29%). Six patients died from secondary infection or uncontrolled systemic inflammation., Discussion: Although impaired immunity due to IEI may be a predisposing factor for severe COVID-19, most of our patients with IEI who acquired the SARS-CoV-2 infection developed a well-tolerated infection and survived, as have more than 80% of worldwide reported patients to date. An impaired immune or inflammatory response may be a predisposing factor for some and a protective factor for others. A systematic review of the literature could help identify those patients at risk of severe disease and complications. Healthcare-associated infections should be aggressively prevented., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The coronavirus (COVID-19) pandemic has challenged the dental health profession in an unprecedented manner. Suspension of elective dental care across the United States during the initial phase of the pandemic was necessary to prevent viral transmission. The emergency dental care that was provided had to be tailored to minimize the generation of aerosols. With the suspension of elective care, over time, the proportion of dental emergencies was anticipated to rise. Dentists who care for children have continued to provide emergency dental treatment to this vulnerable population. Treatment decisions for pediatric dental emergencies had to be tailored to principles of public health that best mitigated risk of viral transmission. Decisions needed to balance the benefits of chosen treatment modality for the individual child with the risk of viral transmission to dental professionals and their staff, patients, and community. The paucity of reliable research for dentists to aid in clinical decision making may have left careproviders feeling ethically and morally insecure in shifting from a patient-centered to a community-centered paradigm. We present analysis of four pediatric emergency case scenarios that are representative of those likely to present to a private practice, academic setting, or emergency department during the COVID-19 pandemic. This analysis aims to empower dentists who care for children to implement the American Dental Association's Principles of Ethics and Code of Professional Conduct within the context of a global health crisis., (Copyright 2021 The Journal of Clinical Ethics. All rights reserved.)

Domino liver transplantation (DLT) has been used widely in patients with hereditary amyloid transthyretin (ATTR) amyloidosis. New-onset polyneuropathy in recipients of DLT has been reported, but there are few cases of cardiac involvement reported. We aimed to perform a cross-sectional study for ATTR amyloidosis with cardiomyopathy (ATTR-CM) in DLT recipients. We evaluated 23 living DLT recipients a median of 9 years since DLT at 2 referral centers with a systematic cardiac evaluation, including bone scintigraphy. Median age was 72 years, 91% had hypertension, 35% had diabetes mellitus, 67% had chronic renal failure, and 8 patients (35%) developed new-onset polyneuropathy. Only 13% had a normal electrocardiogram and a normal echocardiography, and most of them showed some conduction disturbance or increase in left ventricular wall thickness, but only 1 patient with a Glu89Lys mutation developed ATTR-CM diagnosed by bone scintigraphy and endomyocardial biopsy. None of the recipients of a DLT with Val30Met mutation showed cardiac involvement by bone scintigraphy. In conclusion, DLT from Val30Met donors seems to be safe regarding the development of ATTR-CM. Evaluation of cardiomyopathy in DLT recipients is challenging due to concomitant comorbidities and in this context, bone scintigraphy can be helpful to evaluate ATTR-CM., (© 2020 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Unlabelled: Patients with acute and chronic liver disease often require admission to intensive care unit (ICU) and mechanical ventilation support before liver transplantation (LT). Rapid disease progression and high mortality on LT waiting lists makes live donor LT (LDLT) an attractive option for this patient population., Methods: During 2000 to 2011, all ICU-bound and mechanically ventilated patients receiving an LDLT (n = 7) were compared to patients receiving a deceased donor LT (DDLT) (n = 38)., Results: Both groups were comparable regarding length of pretransplant ICU stay (DDLT: 2 [1-31] days vs LDLT: 2 [1-8] days; P = 0.2), days under mechanical ventilation (DDLT: 2 [1-31] days vs LDLT: 2 [1-5] days; P = 0.2), pretransplant dialysis (DDLT: 45% vs LDLT: 43%; P = 1) and model for end-stage liver disease score (DDLT: 33 ± 8 vs LDLT: 33 ± 10; P = 0.911). Live donors median evaluation time was 24 hours (18-561 hours). As expected, median time on waiting list was significantly lower in the LDLT group (DDLT: 13 [0-1704] days vs LDLT: 10 [1-33] days; P = 0.008). Incidence of postoperative complications was numerically, albeit not significantly higher in the DDLT versus LDLT (68% vs 29%; P = 0.08). No difference was detected between LDLT and DDLT patients regarding 1-year (DDLT: 76% vs LDLT: 85%), 3-year (DDLT: 68% vs LDLT: 85%), and 5-year (DDLT: 68% vs LDLT: 85%) graft and patient survivals (P = 0.41). No severe donor complication occurred after live donation., Conclusions: The LDLT may provide a faster access to transplantation and therefore, offers an alternative treatment option for critically ill patients requiring ICU care and mechanical ventilation support at the time of transplantation.

Introduction: Specific developmental language disorder (SDLD) is a diagnostic entity in which language is expected to be the only cognitive function that is affected. Nevertheless, difficulties in other cognitive functions may also appear, either because the language disorder is an expression of an underlying condition or because the retarded language development gives rise to cognitive deficits in general., Aim: To determine whether there are any differences in the cognitive performance of children with SDLD and that of children who have developed normally., Subjects and Methods: The study involved a sample of 51 children with SDLD, aged between 6 and 16 years, and 49 children in a control group, who were paired by chronological age, sex and socioeconomic level. Verbal cognitive capacity, attention, memory, visual-constructional and executive functioning were all evaluated., Results: Statistically and clinically significant differences were found in the verbal-type skills, such as language comprehension and verbal cognitive capacity, which showed effect sizes of -1.31 and -1.33, respectively. In the other functions that were assessed, the performance of the SDLD group was slightly lower than that of the control group, but with no clinically significant differences., Conclusion: These findings show that the group of children with SDLD was well selected, since the only differences between the two groups involve linguistic aspects; moreover, this evidence supports the idea that language and other cognitive functions are relatively independent and that a language disorder would only generate an unspecific general effect in the other cognitive functions.

Unlabelled: Freezing ovarian tissue is acquiring a greater significance due to the increase in oocyte long term survival rates, which provides young women with malignancies an alternative to preserve their fertility., Objectives: 1. Assessing the physiological viability of ovarian tissue auto-transplants. 2. Determining possible differences between the two cryoprotectors that were used: dimethyl sulfoxide (DMSO) and propanediol (PROH)., Design: Experimental and prospective study assessing ovarian tissue viability after freezing and auto-transplantation in eight female sheep., Materials and Methods: A bilateral oophorectomy was performed on the sheep under general anesthesia. The ovarian cortex was dissected and frozen using either DMSO (1.5 M) or PROH (1.5) with saccharose. The thawed tissue was auto-transplanted within the following one to six months, and weekly progesterone measurements were carried out in order to assess ovarian tissue functionality. Once ovulation levels were obtained, the female sheep were continuously exposed to the male in order to obtain the gestation process., Results: Ovulation activity was recovered in seven of the eight female sheep (87.5%) submitted to auto-transplants within an average period of time of 62.8 +/- 9.1 days, as evidenced by serum progesterone levels. These findings were obtained regardless of the cryoprotector used. Two gestations were obtained, and these are evolving normally, as assessed by ultrasonic methods., Conclusions: The present study shows that ovarian function is adequately restored in oophorectomized sheep using ovarian tissue auto-transplantation, and produced the first pregnancies obtained through this technique in Latin America. It is possible to assume that these results can be reproduced in women.

Purpose: Radiographs play an important role in the diagnosis of anomalies and pathology of the oral structures of young children as well as in the interception and management of developmental problems in the dentition. The occlusal film, commonly indicated in the young child, is a helpful tool in establishing a baseline and in revealing certain region-specific dental concerns in a timely fashion. The purpose of this retrospective study was to perform a comprehensive examination of maxillary occlusal radiographs in a clinical pediatric population and to determine the prevalence of dental anomalies and pathology in the premaxilla in children between 3 and 5 years of age., Methods: Radiographs of healthy preschool children (236 males and 264 females), who received their initial examination at the University of Texas-Houston Pediatric Dentistry Graduate Clinic during 1997 and 1998, were reviewed independently by two pediatric dentists, using a 2X magnifying lens and a standard dental light box. Interexaminer discrepancies were resolved by consultation and mutual agreement., Results: Ninety-two (18%) showed no evidence of dental caries, restorations, current pathological conditions, or other anomalies. Frequencies of anomalies such as congenitally missing and supernumerary teeth were consistent with other reports., Conclusions: These observations emphasize the importance of obtaining intraoral radiographs on preschool children who are in apparent good dental health.

Objectives: To assess the oral health status, preventive practices and mutans streptococci (MS) levels among the children of National Guard personnel living in Riyadh, Saudi Arabia., Design: Cross-sectional study of schoolchildren., Setting: Dental Clinic of the National Guard Hospital in Riyadh, Saudi Arabia., Sample and Methods: A sample of 272 5-12-year-old children, 154 males and 118 females (95% Bedouin), were selected from approximately 35 National Guard schools in the Riyadh area. An examination was performed in the dental clinic in the National Guard hospital. Oral hygiene was assessed using the Simplified Debris Index (DI-S); Gingival Index (GI) was used to measure gingival health; dental fluorosis was recorded according to the criteria of Dean. Dental caries (dmft, dmfs, DMFT and DMFS) was recorded according to the recommendations of Haugejorden. Concentration of MS in saline rinse samples was assessed by routine laboratory methods and expressed as colony forming units (CFU) per ml (log10)., Results: There was a high level of dental caries (mean dmft = 3.8 +/- 3.2; mean dmfs = 21.5 +/- 15.7; mean DMFT = 2.0 +/- 1.9; mean DMFS = 3.1 +/- 3.7). Only 0.7% of the children had no caries experience (dmft + DMFT). MS levels ranged from 0 to 7.5 x 10(5) CFU per ml (mean MS = 4.10 +/- 0.90 log10 CFU per ml). A significant relationship between MS and caries experience was observed (P = 0.003). Mild fluorosis was observed in 14% of the children. Oral hygiene scores indicated that most of the examined tooth surfaces had detectable plaque (mean DI-S = 1.78). Gingivitis was present in 100% of the children and was considered moderate to severe in 14% (mean GI = 1.18)., Conclusions: The study revealed a high level of oral diseases and poor oral hygiene in the study population and a need for therapeutic and preventive measures.

The general objective of this study was to investigate the relationship between parental awareness, habits, and social factors in a particular parent population and the occurrence of baby bottle tooth decay (BBTD) in their children. The sample consisted of Hispanic, Black, and White families and included 100 parents with 100 children from the Pediatric Clinic and the Pediatric Dentistry Clinic at Houston Medical Center, University of Texas, Houston. Questionnaires including information related to demographic data, educational level, marital status, baby care, and knowledge and beliefs about BBTD were completed by the parents. Each child was examined with mouth mirror and tongue blade to determine the presence of BBTD. Overall, 19 of the children were found to have BBTD. The racial distribution of the children with and without BBTD was statistically significant (P = 0.03) with the Hispanic population being over-represented in the BBTD group (72.2% versus 37.0%) and Blacks under-represented (16.2% versus 50.6%). The ages at which babies with BBTD were weaned from the bottle were significantly (P < 0.001) higher than those with no BBTD, and those weaned after 14 months of age were more likely to have BBTD. The percentage of babies with BBTD weaned from the bottle after 14 months old was higher (36.8%) than babies without the condition (26.5%). Awareness of BBTD was generally lower among parents of the BBTD children than parents of children without BBTD, as reflected by the feeding patterns of their children and their responses to questions dealing with their knowledge of BBTD.

An important goal in pediatric dentistry is to decrease the prevalence of dental decay from a very early stage. One factor that increases that rate is the presence of a high number of mutans streptococci (MS) in a child's mouth. Since it is generally known that a child's first contact with the environment is made with family members, specifically the mother, we studied the interrelationships between MS and dental caries experience among a group of children and their parents representing different racial groups. Both clinical and microbiological data were obtained to determine correlations between parent or grandparent and child caries experience and MS. Intragroup and intergroup comparisons between black, white, and Hispanic families were made with respect to caries and microbiological parameters. The Hispanic adults and children tended to have higher caries experience than in the black and white groups. Significant correlations between MS levels and most measures of caries experience (P < 0.05) were observed in children and adults. Although mother-child correlations for caries experience were highly significant (P < 0.01), the mother-child correlation for MS infection levels was low and not statistically significant (P > 0.05).

Dens evaginatus is a disturbance in tooth formation that appears clinically as an accessory occlusal tuberculated cusp composed of enamel and dentin, usually enclosing pulp tissue. The tubercle often fractures or is worn away, with subsequent pulp exposure leading to pulpal inflammation, necrosis, and periapical inflammation. When this happens to an immature tooth, diagnosis may be complicated by the similarity in radiographic appearance of the periapical lesion and the dental follicle. The management of such teeth may be complicated because of their immaturity. A case report of multiple abraded dens evaginatus with pulp necrosis is presented that illustrates 1) the difficulty of diagnosing otherwise apparently healthy teeth associated with periapical lesions and sinus tracts, and 2) their management and treatment complications including recurrent infections and root fractures.

This study compared the sedative effectiveness of orally administered ketamine to a combination of oral meperidine/promethazine (Demerol/Phenergan) in two groups of children. One group received ketamine at a dose of 6 mg/kg and the other group received meperidine/promethazine combination at a dose of 2 mg/kg and 0.5 mg/kg, respectively. All children received nitrous oxide 30-50% titrated to effect. A four-point modification of the Houpt et al. rating scale for the overall behavior was used in the evaluations. The quality of sedation, as rated by subjective measurement of overall behavior (sleep, crying, body movement), was higher in the ketamine group (borderline significance; P = 0.07). Mean onset time was significantly shorter (P < 0.001) for ketamine (20.5 min) than meperidine/promethazine (42.4 min) and postoperative sleep time (recovery) was also shorter (borderline significance; P = 0.08) for ketamine (55.6 min) than meperidine/promethazine (106.8 min). Operative times were similar, but the placement of rubber dam and local anesthetic were slightly better tolerated in the ketamine group. Vomiting was significantly more prevalent (P = 0.05) among those who received oral ketamine. Vital signs were consistent for the two groups with no oxygen desaturation below 95%.

The purpose of this investigation was to compare the rate of absorption and clearance time of midazolam (Versed) when administered by the submucosal (SM) route), and the intramuscular (IM) route in ten healthy adult volunteers, ranging in age from 25 to 35 years. Each subject received midazolam 0.08 mg/kg, to a maximum of 5 mg, by the SM and IM routes at two week intervals. Vital signs and arterial oxygen saturation levels were monitored every five minutes throughout the 180 minute study period. Blood samples (3 ml) were collected via an intravenous line, prior to midazolam administration and at 2, 5, 10, 20, 30, 45, 60, 90, 120, 150 and 180 minutes, centrifuged and analyzed by gas-liquid chromatography. The mean absorption rates and the mean elimination times of the two routes were not significantly different. The mean peak absorption was reached at 10 minutes by the SM route (80.4 ng/ml) and at 20 minutes (92.0 ng/ml) by the IM route, with considerable individual variability. Vital signs were stable throughout the study period in all subjects with both routes. All subjects reported pain at the injection site during SM injection which continued for up to 48 hours. No pain related to the IM injection was reported.