3,101 research outputs found
The use of axial loaded MRI in place of radiographs for surveillance of Adolescent Idiopathic Scoliosis: one practice's experience and recommendations
P16-10. IL-2 therapy mediates expansion of Treg cells, maintains IL-17 expressing CD4+ T-cells and selectively suppresses HIV specific T-cell responses
The effect of the systemic inflammatory response on plasma vitamin 25 (OH) D concentrations adjusted for albumin
<b>Aim</b><p></p>
To examine the relationship between plasma 25(OH)D, CRP and albumin concentrations in two patient cohorts.<p></p>
<b>Methods</b><p></p>
5327 patients referred for nutritional assessment and 117 patients with critical illness were examined. Plasma 25 (OH) D concentrations were measured using standard methods. Intra and between assay imprecision was <10%.<p></p>
<b>Result</b><p></p>
In the large cohort, plasma 25 (OH) D was significantly associated with CRP (rs = −0.113, p<0.001) and albumin (rs = 0.192, p<0.001). 3711 patients had CRP concentrations ≤10 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 35 to 28 to 14 nmol/l (p<0.001). This decrease was significant when albumin concentrations were reduced between 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 1271 patients had CRP concentrations between 11–80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 31 to 24 to 19 nmol/l (p<0.001). This decrease was significant when albumin concentration were 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 345 patients had CRP concentrations >80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were not significantly altered varying from 19 to 23 to 23 nmol/l. Similar relationships were also obtained in the cohort of patients with critical illness.<p></p>
<b>Conclusion</b><p></p>
Plasma concentrations of 25(OH) D were independently associated with both CRP and albumin and consistent with the systemic inflammatory response as a major confounding factor in determining vitamin D status.<p></p>
Haptoglobin Phenotype, Preeclampsia Risk and the Efficacy of Vitamin C and E Supplementation to Prevent Preeclampsia in a Racially Diverse Population
Haptoglobin's (Hp) antioxidant and pro-angiogenic properties differ between the 1-1, 2-1, and 2-2 phenotypes. Hp phenotype affects cardiovascular disease risk and treatment response to antioxidant vitamins in some non-pregnant populations. We previously demonstrated that preeclampsia risk was doubled in white Hp 2-1 women, compared to Hp 1-1 women. Our objectives were to determine whether we could reproduce this finding in a larger cohort, and to determine whether Hp phenotype influences lack of efficacy of antioxidant vitamins in preventing preeclampsia and serious complications of pregnancy-associated hypertension (PAH). This is a secondary analysis of a randomized controlled trial in which 10,154 low-risk women received daily vitamin C and E, or placebo, from 9-16 weeks gestation until delivery. Hp phenotype was determined in the study prediction cohort (n = 2,393) and a case-control cohort (703 cases, 1,406 controls). The primary outcome was severe PAH, or mild or severe PAH with elevated liver enzymes, elevated serum creatinine, thrombocytopenia, eclampsia, fetal growth restriction, medically indicated preterm birth or perinatal death. Preeclampsia was a secondary outcome. Odds ratios were estimated by logistic regression. Sampling weights were used to reduce bias from an overrepresentation of women with preeclampsia or the primary outcome. There was no relationship between Hp phenotype and the primary outcome or preeclampsia in Hispanic, white/other or black women. Vitamin supplementation did not reduce the risk of the primary outcome or preeclampsia in women of any phenotype. Supplementation increased preeclampsia risk (odds ratio 3.30; 95% confidence interval 1.61-6.82, p<0.01) in Hispanic Hp 2-2 women. Hp phenotype does not influence preeclampsia risk, or identify a subset of women who may benefit from vitamin C and E supplementation to prevent preeclampsia
Variation in surgical demand and time to hip fracture repair: a Canadian database study.
BACKGROUND: Competing demands for operative resources may affect time to hip fracture surgery. We sought to determine the time to hip fracture surgery by variation in demand in Canadian hospitals. METHODS: We obtained discharge abstracts of 151,952 patients aged 65 years or older who underwent surgery for a hip fracture between January, 2004 and December, 2012 in nine Canadian provinces. We compared median time to surgery (in days) when demand could be met within a two-day benchmark and when demand required more days, i.e. clearance time, to provide surgery, overall and stratified by presence of medical reasons for delay. RESULTS: For persons admitted when demand corresponded to a 2-day clearance time, 68% of patients underwent surgery within the 2-day benchmark. When demand corresponded to a clearance time of one week, 51% of patients underwent surgery within 2 days. Compared to demand that could be served within the two-day benchmark, adjusted median time to surgery was 5.1% (95% confidence interval [CI] 4.1-6.1), 12.2% (95% CI 10.3-14.2), and 22.0% (95% CI 17.7-26.2) longer, when demand required 4, 6, and 7 or more days to clear the backlog, respectively. After adjustment, delays in median time to surgery were similar for those with and without medical reasons for delay. CONCLUSION: Increases in demand for operative resources were associated with dose-response increases in the time needed for half of hip fracture patients to undergo surgery. Such delays may be mitigated through better anticipation of day-to-day supply and demand and increased response capability
Risk of congenital anomalies in pregnant users of statin drugs
What is already known about this subjectCholesterol is known to be essential for fetal development.Statins, which inhibit cholesterol production, have therefore been considered as potential teratogens and are contraindicated in pregnancy.Data available thus far on the risks of congenital anomalies associated with statin therapy have come from non-analytic postmarketing surveillance studies.Given the increasing use of statins in women of childbearing age, there is a need for a population-based study on the risks of congenital anomalies associated with gestational statin use.What this study addsIn this pharmacoepidemiological study, we determined the risk of congenital anomalies in women who filled prescriptions for statins during the first trimester of pregnancy, compared with women who had stopped statins before pregnancy or those who used fibrates during pregnancy.We found no evidence of an increased risk of fetal anomalies among first-trimester statin users, or any discernable pattern of congenital anomalies among live births.However, in the absence of outcome data on nonlive births, conclusions remain uncertain
The AFLOW Fleet for Materials Discovery
The traditional paradigm for materials discovery has been recently expanded
to incorporate substantial data driven research. With the intent to accelerate
the development and the deployment of new technologies, the AFLOW Fleet for
computational materials design automates high-throughput first principles
calculations, and provides tools for data verification and dissemination for a
broad community of users. AFLOW incorporates different computational modules to
robustly determine thermodynamic stability, electronic band structures,
vibrational dispersions, thermo-mechanical properties and more. The AFLOW data
repository is publicly accessible online at aflow.org, with more than 1.7
million materials entries and a panoply of queryable computed properties. Tools
to programmatically search and process the data, as well as to perform online
machine learning predictions, are also available.Comment: 14 pages, 8 figure
Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model
BACKGROUND: Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel(®)) to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model. METHODS: Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC) viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs. RESULTS: Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye). In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected) compared to saline (12 of 12 infected) and a control gel (5 of 7 infected). CONCLUSION: These results suggest that physiologic or microbicide-induced acid immobilization and killing of infected white blood cells may be effective in preventing sexual transmission of cell-associated HIV
Characteristics of non-randomised studies using comparisons with external controls submitted for regulatory approval in the USA and Europe: a systematic review
Objectives: Non-randomised clinical trial designs involving comparisons against external controls or specific standards can be used to support regulatory submissions for indications in diseases that are rare, with high unmet need, without approved therapies and/or where placebo is considered unethical. The objective of this review was to summarise the characteristics of non-randomised trials submitted to the European Medicines Agency (EMA) or Food and Drug Administration (FDA) for indications in haematological cancers, haematological non-malignant conditions, stem cell transplants or rare metabolic diseases. //
Methods: We conducted systematic searches of EMA databases of conditional approvals, exceptional circumstances, or orphan drug designations and FDA inventories of orphan drug designations, accelerated approvals, breakthrough therapy, fast-track and priority approvals. Products were included if reviewed by at least one agency between 2005 and 2017, the primary evidence base was non-randomised trial(s) and the indication was for haematological cancers, stem cell transplantation, haematological conditions or rare metabolic conditions. //
Results: We identified 43 eligible indication-specific products using non-randomised study designs involving comparisons with external controls, submitted to the EMA (n=34) and/or FDA (n=41). Of the 43 indication-specific products, 4 involved matching external controls to the population of a non-randomised interventional study using individual patient-level data (IPD), 12 referred to external controls without IPD and 27 did not explicitly reference external controls. The FDA approved 98% of submissions, with 56% accelerated approvals; most required postapproval confirmatory randomised controlled trials (RCT). The EMA approved 79% of submissions, with a quarter of approvals conditional on completion of a postapproval RCT or additional non-randomised trials. //
Conclusions: There has been a large increase in submissions to the EMA and FDA using non-randomised study designs involving comparisons with external controls in recent years. This study demonstrated that regulators may be willing to approve such submissions, although approvals are often conditional on further confirmatory evidence from postapproval studies
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