ELISA assay for the quantification of ipilimumab in human serum, plasma, milk, and cerebrospinal fluid.

Ipilimumab is an immune checkpoint inhibitor of the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). Ipilimumab has become part of the standard of care for different types of cancer. The efficacy of these treatments is limited due to immune-related toxicity and high economic costs. Dose rationalization studies based on pharmacokinetic data may help to address these limitations. For this purpose, more sensitive analytical methods are needed. We report the development and validation of the first enzyme-linked immunosorbent assay (ELISA) for sensitive determination of ipilimumab concentrations in human serum, plasma, cerebrospinal fluid (CSF), and milk. Our assay is based on the specific capture of ipilimumab by immobilized CTLA-4. The lower limit of quantifications of ipilimumab in serum, plasma, and milk are 50 ng/mL and 10 ng/mL in CSF. The ELISA method showed long-term storage stability for at least one year at -80°C and was successfully cross-validated with ultraperformance liquid chromatography coupled with tandem mass spectrometry. The ELISA method is reliable, relatively inexpensive, and can be used in serum, plasma, CSF, and milk from patients treated with ipilimumab, as evidenced by the analysis of real clinical samples.

Mobilizing community-driven health promotion through community granting programs: a rapid systematic review.

BACKGROUND: Effective health promotion responds to the unique needs of communities. Community granting programs that fund community-driven health promotion initiatives are a potential mechanism to meet those unique needs. While numerous community health-focused programs are available, the various strategies used by granting programs to foster engagement, administer grants and support awardees have not been systematically evaluated. This rapid systematic review explores the administration of community granting programs and how various program components impact process and population health outcomes. METHODS: A systematic search was conducted across three databases: Medline, SocINDEX, and Political Science Database. Single reviewers completed screening, consistent with a rapid review protocol. Studies describing or evaluating community granting programs for health or public health initiatives were included. Data regarding program characteristics were extracted and studies were evaluated for quality. A convergent integrated approach was used to analyze quantitative and qualitative findings. RESULTS: Thirty-five community granting programs, described in 36 studies, were included. Most were descriptive reports or qualitative studies conducted in the USA. Program support for grant awardees included technical assistance, workshops and training, program websites, and networking facilitation. While most programs reported on process outcomes, few reported on community or health outcomes; such outcomes were positive when reported. Programs reported that many funded projects were likely sustainable beyond program funding, due to the development of awardee skills, new partnerships, and securing additional funding. From the perspectives of program staff and awardees, facilitators included the technical assistance and workshops provided by the programs, networking amongst awardees, and the involvement of community members. Barriers included short timelines to develop proposals and allocate funds. CONCLUSIONS: This review provides a comprehensive overview of health-related community granting programs. Grant awardees benefit from technical assistance, workshops, and networking with other awardees. Project sustainability is enhanced by the development of new community partnerships and grant-writing training for awardees. Community granting programs can be a valuable strategy to drive community health, with several key elements that enhance community mobilization. REGISTRATION: PROSPERO #CRD42023399364.

A multiplex UPLC-MS/MS method for the quantification of three PD-L1 checkpoint inhibitors, atezolizumab, avelumab, and durvalumab, in human serum.

BACKGROUND AND AIM: To support pharmacokinetic studies, a multiplex UPLC-MS/MS assay was developed and validated to quantify PD-L1 checkpoint inhibitors atezolizumab, avelumab, and durvalumab in serum. METHODS: A bottom-up sample pre-treatment procedure was developed to determine atezolizumab, avelumab, and durvalumab in serum. This procedure consisted of (1) precipitation of the monoclonal antibody with ammonium sulfate, (2) reduction with dithiothreitol, (3) denaturation with methanol, and (4) tryptic digestion of the protein. The unique signature peptides resulting after sample pre-treatment of the antibodies were measured using UPLC-MS/MS with a total run time of 11 minutes. The clinical application was evaluated by analyzing 114 atezolizumab patient samples. RESULTS: The developed method was found to be accurate and precise for all three analytes over a concentration range of 3.00-150 µg/mL. No endogenous interference was present in serum samples. Cross-interference experiments showed no cross-analyte interference and acceptable cross-internal standard interference. In addition, no substantial carry-over was observed. The stable isotopically labeled signature peptides were most effective in compensating for matrix effects. Recovery based on back-calculated concentrations of calibration standards and quality control samples was found to be high. The analytes were stable for at least three freeze-thaw cycles, for 42 hours at processing conditions, for at least two days at 2-8°C in the final extract, for five days before re-injection analysis at 4°C, and long-term for at least 11 months at -70°C. The assay was tested for its applicability in clinical practice. For this purpose, 114 atezolizumab patient samples were measured. CONCLUSION: A multiplex UPLC-MS/MS assay was developed and validated to quantify atezolizumab, avelumab, and durvalumab in human serum. The applicability of this method was demonstrated by the analysis of clinical atezolizumab samples. The method is suitable to support clinical pharmacokinetic studies involving atezolizumab, avelumab, or durvalumab.

Etrolizumab-s fails to control E-Cadherin-dependent co-stimulation of highly activated cytotoxic T cells.

Despite promising preclinical and earlier clinical data, a recent phase III trial on the anti-ß7 integrin antibody etrolizumab in Crohn's disease (CD) did not reach its primary endpoint. The mechanisms leading to this outcome are not well understood. Here we characterize the ß7+ T cell compartment from patients with CD in comparison to cells from individuals without inflammatory bowel disease. By flow cytometric, transcriptomic and functional profiling of circulating T cells, we find that triple-integrin-expressing (α4+ß7+ß1hi) T cells have the potential to home to the gut despite α4ß7 blockade and have a specific cytotoxic signature. A subset of triple-integrin-expressing cells readily acquires αE expression and could be co-stimulated via E-Cadherin-αEß7 interactions in vitro. Etrolizumab-s fails to block such αEß7 signalling at high levels of T cell stimulation. Consistently, in CD patients treated with etrolizumab, T cell activation correlates with cytotoxic signatures. Collectively, our findings might add one important piece to the puzzle to explain phase III trial results with etrolizumab, while they also highlight that αEß7 remains an interesting target for future therapeutic approaches in inflammatory bowel disease.

Estimating the completeness of physician billing claims for diabetes case ascertainment: a multiprovince investigation. / Estimation de l'exhaustivité des demandes de remboursement des médecins dans une optique de détermination des cas de diabète : étude menée dans plusieurs provinces.

INTRODUCTION: Previous research has suggested that how physicians are paid may affect the completeness of billing claims for estimating chronic disease. The purpose of this study is to estimate the completeness of physician billings for diabetes case ascertainment. METHODS: We used administrative data from eight Canadian provinces covering the period 1 April 2014 to 31 March 2016. The patient cohort was stratified into two mutually exclusive groups based on their physician remuneration type: fee-for-service (FFS), for those paid only on that basis; and non-fee-for-service (NFFS). Using diabetes prescription drug data as our reference data source, we evaluated whether completeness of disease case ascertainment varied with payment type. Diabetes incidence rates were then adjusted for completeness of ascertainment. RESULTS: The cohort comprised 86 110 patients. Overall, equal proportions received their diabetes medications from FFS and NFFS physicians. Overall, physician payment method had little impact upon the percentage of missed diabetes cases (FFS, 14.8%; NFFS, 12.2%). However, the difference in missed cases between FFS and NFFS varied widely by province, ranging from -1.0% in Nova Scotia to 29.9% in Newfoundland and Labrador. The difference between the observed and adjusted disease incidence rates also varied by province, ranging from 22% in Prince Edward Island to 4% in Nova Scotia. CONCLUSION: The difference in the loss of cases by physician remuneration method varied across jurisdictions. This loss may contribute to an underestimation of disease incidence. The method we used could be applied to other chronic diseases for which drug therapy could serve as reference data source.

Differential Effects of Ontamalimab Versus Vedolizumab on Immune Cell Trafficking in Intestinal Inflammation and Inflammatory Bowel Disease.

BACKGROUND AND AIMS: The anti-MAdCAM-1 antibody ontamalimab demonstrated efficacy in a phase II trial in ulcerative colitis and results of early terminated phase III trials are pending, but its precise mechanisms of action are still unclear. Thus, we explored the mechanisms of action of ontamalimab and compared it to the anti-α4ß7 antibody vedolizumab. METHODS: We studied MAdCAM-1 expression with RNA sequencing and immunohistochemistry. The mechanisms of action of ontamalimab were assessed with fluorescence microscopy, dynamic adhesion and rolling assays. We performed in vivo cell trafficking studies in mice and compared ontamalimab and vedolizumab surrogate [-s] antibodies in experimental models of colitis and wound healing. We analysed immune cell infiltration under anti-MAdCAM-1 and anti-α4ß7 treatment by single-cell transcriptomics and studied compensatory trafficking pathways. RESULTS: MAdCAM-1 expression was increased in active inflammatory bowel disease. Binding of ontamalimab to MAdCAM-1 induced the internalization of the complex. Functionally, ontamalimab blocked T cell adhesion similar to vedolizumab, but also inhibited L-selectin-dependent rolling of innate and adaptive immune cells. Despite conserved mechanisms in mice, the impact of ontamalimab-s and vedolizumab-s on experimental colitis and wound healing was similar. Single-cell RNA sequencing demonstrated enrichment of ontamalimab-s-treated lamina propria cells in specific clusters, and in vitro experiments indicated that redundant adhesion pathways are active in these cells. CONCLUSIONS: Ontamalimab has unique and broader mechanisms of action compared to vedolizumab. However, this seems to be compensated for by redundant cell trafficking circuits and leads to similar preclinical efficacy of anti-α4ß7 and anti-MAdCAM-1 treatment. These results will be important for the interpretation of pending phase III data.

Limited Dose-Dependent Effects of Vedolizumab on Various Leukocyte Subsets.

OBJECTIVES: The anti-α4ß7 integrin antibody vedolizumab (VDZ) is successfully used for the treatment of inflammatory bowel diseases. However, only a subgroup of patients respond to therapy. VDZ is administered at a fixed dose, leading to a wide range of serum concentrations in patients. Previous work from our group showed a dose-dependent preferential binding of VDZ to effector compared with regulatory CD4 + T cells. Therefore, we aimed to determine the dose-dependent binding profile of VDZ to other leukocyte subsets. METHODS: We characterized α4ß7 integrin expression on CD8 + T cells, CD19 + B cells, CD14 + monocytes, natural killer cells, and eosinophils from patients with inflammatory bowel disease and healthy controls. We studied the binding of VDZ to these cells at different concentrations and investigated the functional consequences for dynamic adhesion and transmigration in vitro . RESULTS: The expression of α4ß7 differed between the analyzed leukocyte subsets and was significantly higher on eosinophils from inflammatory bowel disease patients compared with controls. Almost all α4ß7-expressing cells from these subsets were bound by VDZ at a concentration of 10 µg/mL. Dynamic cell adhesion was significantly impaired in all subsets, but there were no dose-dependent differences in the inhibition of adhesion. DISCUSSION: Our data suggest that α4ß7-expressing CD8 + T cells, CD19 + B cells, CD14 + monocytes, natural killer cells, and eosinophils are a target of VDZ. However, there do not seem to be concentration-dependent differences, regarding the effects on these cells in the clinically relevant range. Thus, the reported exposure-efficacy characteristic of VDZ can probably mainly be attributed to CD4 + T-cell subsets.

Optimized sample pre-treatment procedure for the simultaneous UPLC-MS/MS quantification of ipilimumab, nivolumab, and pembrolizumab in human serum.

Ipilimumab, nivolumab, and pembrolizumab are immune checkpoint inhibiting monoclonal antibodies. Their efficacy has been proven to be correlated with clearance, and hence, bioanalytical assays to study their pharmacokinetics are of pivotal importance. We present the first kit-free sample pre-treatment procedure of only three hours for the Ultra-Performance Liquid Chromatography - tandem Mass Spectrometry (UPLC-MS/MS) simultaneous quantification of ipilimumab, nivolumab, and pembrolizumab in human serum. The conventional bottom-up sample pre-treatment steps for protein MS bioanalysis including pre-digestion purification, denaturation, reduction, alkylation, and digestion were optimized in terms of sensitivity and reproducibility. In the final, optimal sample pre-treatment procedure, samples were purified by protein precipitation with saturated ammonium sulfate solution, reduced with dithiothreitol, denatured with methanol, and digested with trypsin. The method was then validated according to European Medicines Agency (EMA) and the United States Food and Drug Administration (FDA) guidelines for bioanalytical method validation, and 4-6-20 acceptance criteria were applied. This method was selective, accurate, and precise within the range of 3-200 µg/mL for all analytes. The validated developed assay was applied to determine ipilimumab, nivolumab, and pembrolizumab concentrations in patient serum, and the results were compared to enzyme-linked immunosorbent assay (ELISA) results.

Population coverage of the Canadian Chronic Disease Surveillance System: a survey of the contents of health insurance registries across Canada. / Couverture de la population dans le Système canadien de surveillance des maladies chroniques : enquête sur le contenu des registres d'assurance-maladie au Canada.

INTRODUCTION: Health insurance registries, which capture insurance coverage and demographic information for entire populations, are a critical component of population health surveillance and research when using administrative data. Lack of standardization of registry information across Canada's provinces and territories could affect the comparability of surveillance measures. We assessed the contents of health insurance registries across Canada to describe the populations covered and document registry similarities and differences. METHODS: A survey about the data and population identifiers in health insurance registries was developed by the study team and representatives from the Public Health Agency of Canada. The survey was completed by key informants from most provinces and territories and then descriptively analyzed. RESULTS: Responses were received from all provinces; partial responses were received from the Northwest Territories. Demographic information in health insurance registries, such as primary address, date of birth and sex, were captured in all jurisdictions. Data captured on familial relationships, ethnicity and socioeconomic status varied among jurisdictions, as did start and end dates of coverage and frequency of registry updates. Identifiers for specific populations, such as First Nations individuals, were captured in some, but not all jurisdictions. CONCLUSION: Health insurance registries are a rich source of information about the insured populations of the provinces and territories. However, data heterogeneity may affect who is included and excluded in population surveillance estimates produced using administrative health data. Development of a harmonized data framework could support timely and comparable population health research and surveillance results from multi-jurisdiction studies.

Quantification of anti-SARS-CoV-2 antibodies in human serum with LC-QTOF-MS.

The aim of this study was to develop the first quantitative serological test for anti-SARS-CoV-2 antibodies in human serum with liquid chromatography - quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Other assays, mostly immunoassays, are only qualitative or semi-quantitative, and hence, actual antibody concentrations after SARS-CoV-2 infection are unknown. In our assay, anti-SARS-CoV-2 antibodies were isolated with spike protein subunit 1 (S1) coupled to magnetic beads. IgG1 signature peptide GPSVFPLAPSSK was selected for quantification using ipilimumab calibration standards and SILuMAb K1 as the stable-isotope labeled internal standard. The anti-SARS-CoV-2 IgG1 calibration range was from 1.35 to 135 nM. Inter-assay accuracies were between 98.8%- 107% with inter-assay precisions between 8.37%- 13.5% measured at 3 concentration levels on three separate occasions. Anti-SARS-CoV-2 IgG1 antibodies were quantified in PCR-positive patients with mild to severe symptoms. IgM signature peptide DGFFGVPR was detected in patients that recently recovered from COVID-19. A unique and quantitative LC-QTOF-MS method to quantify anti-SARS-CoV-2 IgG1 in serum was successfully developed and its clinical applicability has been demonstrated.

Simultaneous quantification of abemaciclib and its active metabolites in human and mouse plasma by UHPLC-MS/MS.

Abemaciclib is the third cyclin-dependent kinase 4 and 6 inhibitor approved for the treatment of advanced or metastatic breast cancer. In humans, abemaciclib is extensively metabolized by CYP3A4 with the formation of three active metabolites: N-desethylabemaciclib (M2), hydroxyabemaciclib (M20) and hydroxy-N-desethylabemaciclib (M18). These metabolites showed similar potency compared to the parent drug and were significantly abundant in plasma circulation. Thus, M2, M20, and M18 may contribute to the clinical activity of abemaciclib. For this reason, an UHPLC-MS/MS method for the simultaneous quantification of abemaciclib and its active metabolites in human and mouse plasma was developed and validated to support further clinical or preclinical investigations on this drug. Samples were processed by protein precipitation with acetonitrile, followed by supernatant dilution and filtration. Chromatographic separation was performed on a Kinetex C18 column (150 × 2.1 mm ID, 2.6 µm) using gradient elution with 10 mM ammonium bicarbonate in water (eluent A) and in methanol-water (9:1, v/v, eluent B). This method was selective, linear, accurate and precise within the range of 1-600 ng/mL for abemaciclib, 0.5-300 ng/mL for M2 and M20, and 0.2-120 ng/mL for M18. Furthermore, stability of the analytes in human and mouse plasma samples in several conditions was demonstrated. Finally, this assay was successfully used in a preclinical pharmacokinetic study, where abemaciclib and its active metabolites were identified and quantified. Inter-species differences between human and mouse samples were encountered, especially in the formation of M20, where isomers of this compound were detected in mouse plasma, but not in human plasma. This was confirmed by high resolution-mass spectrometry (HR-MS) measurements.

Trained Immunity-Promoting Nanobiologic Therapy Suppresses Tumor Growth and Potentiates Checkpoint Inhibition.

Trained immunity, a functional state of myeloid cells, has been proposed as a compelling immune-oncological target. Its efficient induction requires direct engagement of myeloid progenitors in the bone marrow. For this purpose, we developed a bone marrow-avid nanobiologic platform designed specifically to induce trained immunity. We established the potent anti-tumor capabilities of our lead candidate MTP10-HDL in a B16F10 mouse melanoma model. These anti-tumor effects result from trained immunity-induced myelopoiesis caused by epigenetic rewiring of multipotent progenitors in the bone marrow, which overcomes the immunosuppressive tumor microenvironment. Furthermore, MTP10-HDL nanotherapy potentiates checkpoint inhibition in this melanoma model refractory to anti-PD-1 and anti-CTLA-4 therapy. Finally, we determined MTP10-HDL's favorable biodistribution and safety profile in non-human primates. In conclusion, we show that rationally designed nanobiologics can promote trained immunity and elicit a durable anti-tumor response either as a monotherapy or in combination with checkpoint inhibitor drugs.

Immunology of IL-12: An update on functional activities and implications for disease.

As its first identified member, Interleukin-12 (IL-12) named a whole family of cytokines. In response to pathogens, the heterodimeric protein, consisting of the two subunits p35 and p40, is secreted by phagocytic cells. Binding of IL-12 to the IL-12 receptor (IL-12R) on T and natural killer (NK) cells leads to signaling via signal transducer and activator of transcription 4 (STAT4) and subsequent interferon gamma (IFN-γ) production and secretion. Signaling downstream of IFN-γ includes activation of T-box transcription factor TBX21 (Tbet) and induces pro-inflammatory functions of T helper 1 (TH1) cells, thereby linking innate and adaptive immune responses. Initial views on the role of IL-12 and clinical efforts to translate them into therapeutic approaches had to be re-interpreted following the discovery of other members of the IL-12 family, such as IL-23, sharing a subunit with IL-12. However, the importance of IL-12 with regard to immune processes in the context of infection and (auto-) inflammation is still beyond doubt. In this review, we will provide an update on functional activities of IL-12 and their implications for disease. We will begin with a summary on structure and function of the cytokine itself as well as its receptor and outline the signal transduction and the transcriptional regulation of IL-12 secretion. In the second part of the review, we will depict the involvement of IL-12 in immune-mediated diseases and relevant experimental disease models, while also providing an outlook on potential translational approaches.

Trends in chronic disease incidence rates from the Canadian Chronic Disease Surveillance System. / Tendances des taux d'incidence des maladies chroniques d'après le Système canadien de surveillance des maladies chroniques.

INTRODUCTION: The Public Health Agency of Canada's Canadian Chronic Disease Surveillance System (CCDSS) produces population-based estimates of chronic disease prevalence and incidence using administrative health data. Our aim was to assess trends in incidence rates over time, trends are essential to understand changes in population risk and to inform policy development. METHODS: Incident cases of diagnosed asthma, chronic obstructive pulmonary disease (COPD), diabetes, hypertension, ischemic heart disease (IHD), and stroke were obtained from the CCDSS online infobase for 1999 to 2012. Trends in national and regional incidence estimates were tested using a negative binomial regression model with year as a linear predictor. Subsequently, models with year as a restricted cubic spline were used to test for departures from linearity using the likelihood ratio test. Age and sex were covariates in all models. RESULTS: Based on the models with year as a linear predictor, national incidence rates were estimated to have decreased over time for all diseases, except diabetes; regional incidence rates for most diseases and regions were also estimated to have decreased. However, likelihood ratio tests revealed statistically significant departures from a linear year effect for many diseases and regions, particularly for hypertension. CONCLUSION: Chronic disease incidence estimates based on CCDSS data are decreasing over time, but not at a constant rate. Further investigations are needed to assess if this decrease is associated with changes in health status, data quality, or physician practices. As well, population characteristics that may influence changing incidence trends also require exploration.

The Canadian Chronic Disease Surveillance System: A model for collaborative surveillance.

Chronic diseases have a major impact on populations and healthcare systems worldwide. Administrative health data are an ideal resource for chronic disease surveillance because they are population-based and routinely collected. For multi-jurisdictional surveillance, a distributed model is advantageous because it does not require individual-level data to be shared across jurisdictional boundaries. Our objective is to describe the process, structure, benefits, and challenges of a distributed model for chronic disease surveillance across all Canadian provinces and territories (P/Ts) using linked administrative data. The Public Health Agency of Canada (PHAC) established the Canadian Chronic Disease Surveillance System (CCDSS) in 2009 to facilitate standardized, national estimates of chronic disease prevalence, incidence, and outcomes. The CCDSS primarily relies on linked health insurance registration files, physician billing claims, and hospital discharge abstracts. Standardized case definitions and common analytic protocols are applied to the data for each P/T; aggregate data are shared with PHAC and summarized for reports and open access data initiatives. Advantages of this distributed model include: it uses the rich data resources available in all P/Ts; it supports chronic disease surveillance capacity building in all P/Ts; and changes in surveillance methodology can be easily developed by PHAC and implemented by the P/Ts. However, there are challenges: heterogeneity in administrative databases across jurisdictions and changes in data quality over time threaten the production of standardized disease estimates; a limited set of databases are common to all P/Ts, which hinders potential CCDSS expansion; and there is a need to balance comprehensive reporting with P/T disclosure requirements to protect privacy. The CCDSS distributed model for chronic disease surveillance has been successfully implemented and sustained by PHAC and its P/T partners. Many lessons have been learned about national surveillance involving jurisdictions that are heterogeneous with respect to healthcare databases, expertise and analytical capacity, population characteristics, and priorities.

An Assessment of the Influence of the Industry Distribution Chain on the Oxygen Levels in Commercial Modified Atmosphere Packaged Cheddar Cheese Using Non-Destructive Oxygen Sensor Technology.

The establishment and control of oxygen levels in packs of oxygen-sensitive food products such as cheese is imperative in order to maintain product quality over a determined shelf life. Oxygen sensors quantify oxygen concentrations within packaging using a reversible optical measurement process, and this non-destructive nature ensures the entire supply chain can be monitored and can assist in pinpointing negative issues pertaining to product packaging. This study was carried out in a commercial cheese packaging plant and involved the insertion of 768 sensors into 384 flow-wrapped cheese packs (two sensors per pack) that were flushed with 100% carbon dioxide prior to sealing. The cheese blocks were randomly assigned to two different storage groups to assess the effects of package quality, packaging process efficiency, and handling and distribution on package containment. Results demonstrated that oxygen levels increased in both experimental groups examined over the 30-day assessment period. The group subjected to a simulated industrial distribution route and handling procedures of commercial retailed cheese exhibited the highest level of oxygen detected on every day examined and experienced the highest rate of package failure. The study concluded that fluctuating storage conditions, product movement associated with distribution activities, and the possible presence of cheese-derived contaminants such as calcium lactate crystals were chief contributors to package failure.

Dual oxidase maturation factor 1 (DUOXA1) overexpression increases reactive oxygen species production and inhibits murine muscle satellite cell differentiation.

BACKGROUND: Dual oxidase maturation factor 1 (DUOXA1) has been associated with the maturation of the reactive oxygen species (ROS) producing enzyme, dual oxidase 1 (DUOX1) in the adult thyroid. However, ROS have also been implicated in the development of several tissues. We found that activated muscle satellite cells and primary myoblasts isolated from mice express robust levels of DUOXA1 and that its levels are altered as cells differentiate. RESULTS: To determine whether DUOXA1 levels affect muscle differentiation, we used an adenoviral construct (pCMV5-DUOXA1-GFP) to drive constitutive overexpression of this protein in primary myoblasts. High levels of DUOXA1 throughout myogenesis resulted in enhanced H2O2 production, fusion defects, reduced expression of early (myogenin) and late (myosin heavy chain) markers of differentiation, and elevated levels of apoptosis compared to control cells infected with an empty adenoviral vector (pCMV5-GFP). DUOXA1 knockdown (using a DUOXA1 shRNA construct) resulted in enhanced differentiation compared to cells subjected to a control shRNA, and subjecting DUOXA1 overexpressing cells to siRNAs targeting DUOX1 or apoptosis signal-regulating kinase 1 (ASK1) rescued the phenotype. CONCLUSIONS: This study represents the first to demonstrate the importance of DUOXA1 in skeletal muscle myoblasts and that DUOXA1 overexpression in muscle stem cells induces apoptosis and inhibits differentiation through DUOX1 and ASK1.

Automedicação em acadêmicos do curso de medicina / Self-medication in academics from medical school

Objetivo: Avaliar a automedicação em estudantes do curso de Medicina da Universidade de RibeirãoPreto (UNAERP) no ano de 2008. Métodos: Estudo transversal quantitativo, realizado no ano de 2008, no qual 200 alunos do curso de Medicina da UNAERP responderam a um questionário autoaplicado, contendo questões de múltipla escolha sobre a prática da automedicação, no intuito de conhecer aspectos do consumo de medicamentos. Para análise estatística foi empregado o teste de correlação de Pearson. Considerou-se como base o intervalo de confiança de 95%. O estudo foi aprovado pelo Comitê de Ética da UNAERP. Resultados: Observaram-se 58,5% de participantes do sexo feminino. A média de idade foi de 21,5 anos. A prevalência da automedicação foi de 92,0%. As prevalências entre os alunos das diferentes etapas do curso não foram significativamente diferentes: 86,6%, 90,0%, 93,3%,94,4% e 97,1%, respectivamente, entre os alunos do 1º ao 4º ano e internato. A aquisição de medicamentos controlados, sem apresentação da prescrição, ocorreu entre 6,5% dos alunos e 69,5% responderam já terem indicado medicamentos para outras pessoas...

Objective: Evaluate the self-medication by students of University of Medicine of Ribeirão Preto (UNAERP) in 2008. Methods: A quantitative cross-sectional study conducted throughout 2008 in with 200 medicine students, who answered a self-administered questionnaire containing multiple choice questions regarding self-medication and consumption of medicines. Statistical analysis was employed to test Pearson correlation. The confidence interval considered was of 95%. The study was approved by UNAERP Ethics Committee. Results: There were 58.5% of female participants. The age average was 21.5 years old. The prevalence of self-medication was 92.0%. The prevalence among students from different stages of the course was not significantly different: 86.6%, 90.0%, 93.3%, 94.4% and 97.1%, among the students from, respectively, the 1st to 4th year and from the internship...

Reactive oxygen species and the neuronal fate.

Aberrant or elevated levels of reactive oxygen species (ROS) can mediate deleterious cellular effects, including neuronal toxicity and degeneration observed in the etiology of a number of pathological conditions, including Alzheimer's and Parkinson's diseases. Nevertheless, ROS can be generated in a controlled manner and can regulate redox sensitive transcription factors such as NFκB, AP-1 and NFAT. Moreover, ROS can modulate the redox state of tyrosine phosphorylated proteins, thereby having an impact on many transcriptional networks and signaling cascades important for neurogenesis. A large body of literature links the controlled generation of ROS at low-to-moderate levels with the stimulation of differentiation in certain developmental programs such as neurogenesis. In this regard, ROS are involved in governing the acquisition of the neural fate-from neural induction to the elaboration of axons. Here, we summarize and discuss the growing body of literature that describe a role for ROS signaling in neuronal development.