1,185 research outputs found
Altering HIF-1α through 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure affects coronary vessel development.
Differential tissue hypoxia drives normal cardiogenic events including coronary vessel development. This requirement renders cardiogenic processes potentially susceptible to teratogens that activate a transcriptional pathway that intersects with the hypoxia-inducible factor (HIF-1) pathway. The potent toxin 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is known to cause cardiovascular defects by way of reduced myocardial hypoxia, inhibition of angiogenic stimuli, and alterations in responsiveness of endothelial cells to those stimuli. Our working hypothesis is that HIF-1 levels and thus HIF-1 signaling in the developing myocardium will be reduced by TCDD treatment in vivo during a critical stage and in particularly sensitive sites during heart morphogenesis. This inadequate HIF-1 signaling will subsequently result in outflow tract (OFT) and coronary vasculature defects. Our current data using the chicken embryo model showed a marked decrease in the intensity of immunostaining for HIF-1α nuclear expression in the OFT myocardium of TCDD-treated embryos. This area at the base of the OFT is particularly hypoxic during normal development; where endothelial cells initially form a concentrated anastomosing network known as the peritruncal ring; and where the left and right coronary arteries eventually connect to the aortic lumen. Consistent with this finding, anomalies of the proximal coronaries were detected after TCDD treatment and HIF-1α protein levels decreased in a TCDD dose-dependent manner
Horses with equine recurrent uveitis have an activated CD4+ T-cell phenotype that can be modulated by mesenchymal stem cells in vitro.
Equine recurrent uveitis (ERU) is an immune-mediated disease causing repeated or persistent inflammatory episodes which can lead to blindness. Currently, there is no cure for horses with this disease. Mesenchymal stem cells (MSCs) are effective at reducing immune cell activation in vitro in many species, making them a potential therapeutic option for ERU. The objectives of this study were to define the lymphocyte phenotype of horses with ERU and to determine how MSCs alter T-cell phenotype in vitro. Whole blood was taken from 7 horses with ERU and 10 healthy horses and peripheral blood mononuclear cells were isolated. The markers CD21, CD3, CD4, and CD8 were used to identify lymphocyte subsets while CD25, CD62L, Foxp3, IFNÎł, and IL10 were used to identify T-cell phenotype. Adipose-derived MSCs were expanded, irradiated (to control proliferation), and incubated with CD4+ T-cells from healthy horses, after which lymphocytes were collected and analyzed via flow cytometry. The percentages of T-cells and B-cells in horses with ERU were similar to normal horses. However, CD4+ T-cells from horses with ERU expressed higher amounts of IFNÎł indicating a pro-inflammatory Th1 phenotype. When co-incubated with MSCs, activated CD4+ T-cells reduced expression of CD25, CD62L, Foxp3, and IFNÎł. MSCs had a lesser ability to decrease activation when cell-cell contact or prostaglandin signaling was blocked. MSCs continue to show promise as a treatment for ERU as they decreased the CD4+ T-cell activation phenotype through a combination of cell-cell contact and prostaglandin signaling
Vaccine-preventable haemophilus influenza type B disease burden and cost-effectiveness of infant vaccination in Indonesia.
BACKGROUND: Most of Asia, including Indonesia, does not use Haemophilus influenzae type b (Hib) conjugate vaccines. We estimated total vaccine-preventable disease burden and the cost-effectiveness of Hib conjugate vaccine in Indonesia. METHODS: Hib pneumonia and meningitis incidences for children with access to health care were derived from a randomized vaccine probe study on Lombok Island, Indonesia during 1998-2002. Incidences were adjusted for limited access to care. Health system and patient out-of-pocket treatment cost data were collected concurrent with the probe study. For Hib vaccine in monovalent and combined (with DTP-HepB) presentations, we used 2007 UNICEF vaccine prices of US3.75 per dose. RESULTS: For the 2007 Indonesian birth cohort, Hib vaccine would prevent meningitis in 1 of every 179 children, pneumonia in 1 of every 18 children, and 4.9% of mortality among those younger than 5 years. The total incremental societal costs of introducing Hib vaccine in monovalent and pentavalent presentations were, respectively, US8.93 per child vaccinated. Annual discounted treatment costs averted amounted to 20% of pentavalent vaccine costs. For the pentavalent vaccine, the incremental costs per discounted death and disability adjusted life-year averted amounted to US74, respectively, versus 102 for monovalent vaccine. CONCLUSIONS: Routine infant Hib vaccination would prevent a large burden of pediatric illness and death in Indonesia. Even without external funding support, Hib vaccine will be a highly cost-effective intervention in either a monovalent or pentavalent presentation based on commonly used benchmarks
IntĂ©rĂȘt dâun score de la qualitĂ© de l'Ă©valuation pour l'apprentissage pour Ă©valuer la rĂ©troaction Ă©crite dans la formation postdoctorale en anesthĂ©siologie : Ă©tude de gĂ©nĂ©ralisabilitĂ© et de dĂ©cision
Background: Competency based residency programs depend on high quality feedback from the assessment of entrustable professional activities (EPA). The Quality of Assessment for Learning (QuAL) score is a tool developed to rate the quality of narrative comments in workplace-based assessments; it has validity evidence for scoring the quality of narrative feedback provided to emergency medicine residents, but it is unknown whether the QuAL score is reliable in the assessment of narrative feedback in other postgraduate programs.
Methods: Fifty sets of EPA narratives from a single academic year at our competency based medical education post-graduate anesthesia program were selected by stratified sampling within defined parameters [e.g. resident gender and stage of training, assessor gender, Competency By Design training level, and word count (â„17 or <17 words)]. Two competency committee members and two medical students rated the quality of narrative feedback using a utility score and QuAL score. We used Kendallâs tau-b co-efficient to compare the perceived utility of the written feedback to the quality assessed with the QuAL score. The authors used generalizability and decision studies to estimate the reliability and generalizability coefficients.
Results: Both the facultyâs utility scores and QuAL scores (r = 0.646, p < 0.001) and the traineesâ utility scores and QuAL scores (r = 0.667, p < 0.001) were moderately correlated. Results from the generalizability studies showed that utility scores were reliable with two raters for both faculty (Epsilon=0.87, Phi=0.86) and trainees (Epsilon=0.88, Phi=0.88).
Conclusions: The QuAL score is correlated with faculty- and trainee-rated utility of anesthesia EPA feedback. Both faculty and trainees can reliability apply the QuAL score to anesthesia EPA narrative feedback. This tool has the potential to be used for faculty development and program evaluation in Competency Based Medical Education. Other programs could consider replicating our study in their specialty.Contexte : La qualitĂ© de la rĂ©troaction Ă la suite de lâĂ©valuation dâactivitĂ©s professionnelles confiables (APC) est dâune importance capitale dans les programmes de rĂ©sidence fondĂ©s sur les compĂ©tences. Le score QuAL (Quality of Assessment for Learning) est un outil dĂ©veloppĂ© pour Ă©valuer la qualitĂ© de la rĂ©troaction narrative dans les Ă©valuations en milieu de travail. Sa validitĂ© a Ă©tĂ© dĂ©montrĂ©e dans le cas des commentaires narratifs fournis aux rĂ©sidents en mĂ©decine d'urgence, mais sa fiabilitĂ© nâa pas Ă©tĂ© Ă©valuĂ©e dans d'autres programmes de formation postdoctorale.
MĂ©thodes : Cinquante ensembles de commentaires portant sur des APC d'une seule annĂ©e universitaire dans notre programme postdoctoral en anesthĂ©siologie â un programme fondĂ© sur les compĂ©tences â ont Ă©tĂ© sĂ©lectionnĂ©s par Ă©chantillonnage stratifiĂ© selon des paramĂštres prĂ©Ă©tablis [par exemple, le sexe du rĂ©sident et son niveau de formation, le sexe de l'Ă©valuateur, le niveau de formation en CompĂ©tence par conception, et le nombre de mots (â„17 ou <17 mots)]. Deux membres du comitĂ© de compĂ©tence et deux Ă©tudiants en mĂ©decine ont Ă©valuĂ© la qualitĂ© de la rĂ©troaction narrative Ă l'aide d'un score d'utilitĂ© et d'un score QuAL. Nous avons utilisĂ© le coefficient tau-b de Kendall pour comparer l'utilitĂ© perçue de la rĂ©troaction Ă©crite et sa qualitĂ© Ă©valuĂ©e Ă lâaide du score QuAL. Les auteurs ont utilisĂ© des Ă©tudes de gĂ©nĂ©ralisabilitĂ© et de dĂ©cision pour estimer les coefficients de fiabilitĂ© et de gĂ©nĂ©ralisabilitĂ©.
RĂ©sultats : Les scores d'utilitĂ© et les scores QuAL des enseignants (r = 0,646, p < 0,001) et ceux des Ă©tudiants (r = 0,667, p < 0,001) Ă©taient modĂ©rĂ©ment corrĂ©lĂ©s. Les rĂ©sultats des Ă©tudes de gĂ©nĂ©ralisabilitĂ© ont montrĂ© quâavec deux Ă©valuateurs les scores d'utilitĂ© Ă©taient fiables tant pour les enseignants (Epsilon=0,87, Phi=0,86) que pour les Ă©tudiants (Epsilon=0,88, Phi=0,88).
Conclusions : Le score QuAL est en corrĂ©lation avec l'utilitĂ© de la rĂ©troaction sur les APC en anesthĂ©siologie Ă©valuĂ©e par les enseignants et les Ă©tudiants. Les uns et les autres peuvent appliquer de maniĂšre fiable le score QuAL aux commentaires narratifs sur les APC en anesthĂ©siologie. Cet outil pourrait ĂȘtre utilisĂ© pour le perfectionnement professoral et l'Ă©valuation des programmes dans le cadre dâune formation mĂ©dicale fondĂ©e sur les compĂ©tences. D'autres programmes pourraient envisager de reproduire notre Ă©tude dans leur spĂ©cialitĂ©
T Cells Contain an RNase-Insensitive Inhibitor of APOBEC3G Deaminase Activity
The deoxycytidine deaminase APOBEC3G (A3G) is expressed in human T cells and inhibits HIV-1 replication. When transfected into A3G-deficient epithelial cell lines, A3G induces catastrophic hypermutation by deaminating the HIV-1 genome. Interestingly, studies suggest that endogenous A3G in T cells induces less hypermutation than would be expected. However, to date, the specific deaminase activity of endogenous A3G in human CD4+ T cells has not been examined directly. Here, we compared deaminase activity of endogenous and exogenous A3G in various human cell lines using a standard assay and a novel, quantitative, high-throughput assay. Exogenous A3G in epithelial cell lysates displayed deaminase activity only following RNase treatment, as expected given that A3G is known to form an enzymatically inactive RNA-containing complex. Surprisingly, comparable amounts of endogenous A3G from T cell lines or from resting or activated primary CD4+ T cells exhibited minimal deaminase activity, despite RNase treatment. Specific deaminase activity of endogenous A3G in H9, CEM, and other T cell lines was up to 36-fold lower than specific activity of exogenous A3G in epithelial-derived cell lines. Furthermore, RNase-treated T cell lysates conferred a dose-dependent inhibition to epithelial cell lysates expressing enzymatically active A3G. These studies suggest that T cells, unlike epithelial-derived cell lines, express an unidentified RNase-resistant factor that inhibits A3G deaminase activity. This factor could be responsible for reduced levels of hypermutation in T cells, and its identification and blockade could offer a means for increasing antiretroviral intrinsic immunity of T cells
Implementation and Evaluation of Iron Deficiency Anemia Content in Prenatal Education Classes
Purpose/Background
The purpose of this quality improvement project is to provide and increase educational awareness and knowledge regarding iron deficiency anemia (IDA) in pregnant patients at an urban primary care clinic in Memphis, TN. This project is intended to decrease the number of individuals with IDA in pregnancy while decreasing the occurrence of IDA-related complications in pregnancy. The study aimed to introduce a cost-effective approach to help decrease or eradicate complications related to IDA during pregnancy.
The World Health Organization (WHO) estimates the prevalence of anemia-complicating pregnancies to be more than 40 percent. Pregnant women with IDA residing in low and middle-income countries are at a higher risk of low birth weight, preterm birth, perinatal mortality, and neonatal mortality. Memphis is known as an urban, predominantly Black city, in which studies have shown that the prevalence of Black gravidas was \u3e15 percent in the first trimester, around 20 percent in the second trimester, and close to 50 percent in the third trimester. Introducing IDA educational sessions can beneficially impact Memphis maternal and infant mortality rates and the number of complications and interventions related to IDA.
Methods
Researchers collaborated with the Midwives at Regional One Health Centerâs (ROH) Hollywood Primary Care Clinic in Memphis, TN, to educate 25 pregnant women. The participants were administered a pretest before reviewing the IDA content. After completion of the pretest, an infographic was given to and reviewed with the patient during a 10-minute session. After reviewing the infographic, the participant took a post-test. All women gave consent to participate in this study in their first trimester (before 13 weeks gestation), were 18 or older, and had no known blood disorders or medical conditions that interfere with liver function.
Results
The pretest/post-test showed a significant correlation between IDA educational sessions and increased awareness. The results show the benefits of education in increasing awareness to help prevent pregnant women in Memphis, TN, from developing IDA and related complications.
IDA educational sessions will continue to increase awareness amongst pregnant women. The likelihood of pregnant women complying with iron supplement regimens will steadily increase, thus decreasing the risk of IDA-related complications. Therefore, the results show that providing short educational sessions to mothers in their first trimester are not only cost-effective, but will also improve maternal and infant mortality rates, especially in underserved communities like Memphis, TN.
Implication in Nursing Practice
Pre- and post-tests will be administered before and after the iron deficiency anemia education session. The pre- and post-tests will be used to collect data regarding patient education on iron deficiency anemia in pregnancy before and after the education. This information will help determine if there is a correlation between patients receiving one-on-one education on iron deficiency anemia and their knowledge of patient compliance with iron supplementation. Once the education and data collection is completed, strengths and weaknesses should be identified for improvement throughout the project for more organized and efficient education
Progenitor Cell Therapy for the Treatment of Central Nervous System Injury: A Review of the State of Current Clinical Trials
Recent preclinical work investigating the role of progenitor cell therapies for central nervous system (CNS) injuries has shown potential neuroprotection in the setting of traumatic brain injury (TBI), spinal cord injury (SCI), and ischemic stroke. Mechanisms currently under investigation include engraftment and transdifferentiation, modulation of the locoregional inflammatory milieu, and modulation of the systemic immunologic/inflammatory response. While the exact mechanism of action remains controversial, the growing amount of preclinical data demonstrating the potential benefit associated with progenitor cell therapy for neurological injury warrants the development of well-controlled clinical trials to investigate therapeutic safety and efficacy. In this paper, we review the currently active or recently completed clinical trials investigating the safety and potential efficacy of bone marrow-derived progenitor cell therapies for the treatment of TBI, SCI, and ischemic stroke. Our review of the literature shows that while the preliminary clinical trials reviewed in this paper offer novel data supporting the potential efficacy of stem/progenitor cell therapies for CNS injury, a great deal of additional work is needed to ensure the safety, efficacy, and mechanisms of progenitor cell therapy prior to widespread clinical trials
Protease-activated receptor 4 variant p.Tyr157Cys reduces platelet functional responses and alters receptor trafficking
OBJECTIVEâ: Protease-activated receptor 4 (PAR4) is a key regulator of platelet reactivity and is encoded by F2RL3, which has abundant rare missense variants. We aimed to provide proof of principle that rare F2LR3 variants potentially affect on platelet reactivity and responsiveness to PAR1 antagonist drugs and to explore underlying molecular mechanisms. APPROACH AND RESULTSâ: We identified 6 rare F2RL3 missense variants in 236 cardiac patients, of which the variant causing a tyrosine 157 to cysteine substitution (Y157C) was predicted computationally to affect most on PAR4 structure. Y157C platelets from 3 cases showed reduced responses to PAR4-activating peptide and to α-thrombin compared with controls, but no reduction in responses to PAR1-activating peptide. Pretreatment with the PAR1 antagonist vorapaxar caused lower residual α-thrombin responses in Y157C platelets than in controls, indicating greater platelet inhibition. HEK293 cells transfected with a PAR4 Y157C expression construct had reduced PAR4 functional responses, unchanged total PAR4 expression but reduced surface expression. PAR4 Y157C was partially retained in the endoplasmic reticulum and displayed an expression pattern consistent with defective N-glycosylation. Mutagenesis of Y322, which is the putative hydrogen bond partner of Y157, also reduced PAR4 surface expression in HEK293 cells. CONCLUSIONSâ: Reduced PAR4 responses associated with Y157C result from aberrant anterograde surface receptor trafficking, in part, because of disrupted intramolecular hydrogen bonding. Characterization of PAR4 Y157C establishes that rare F2RL3 variants have the potential to markedly alter platelet PAR4 reactivity particularly after exposure to therapeutic PAR1 antagonists
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