41 research outputs found

    Vitamin D status of 6- to 7-year-old children living in Isfahan, Iran

    Get PDF
    Wstęp: Witamina D ma podstawowe znaczenie dla utrzymania dobrego zdrowia. O niedoborach witaminy D donoszą autorzy z wielu krajów, również tych o dużym stopniu nasłonecznienia. Niniejsze badanie przeprowadzono w celu dokonania oceny stężenia witaminy D u zdrowych dzieci w wieku 6-7 lat, zamieszkałych w Isfahanie, Iran. Materiał i metody: Do badania włączono 513 zdrowych dzieci. Zmierzono u nich stężenie PTH i 25-hydroksywitaminy D (25-OHD) w surowicy. Określono spożycie witaminy D w diecie, czas ekspozycji na słońce w ciągu doby i odsetek powierzchni ciała wystawionej na działanie słońca. Przyjęto, że stężenia 25-OHD wynoszące < 20 ng/ml i 10 ng/ml odpowiadają odpowiednio łagodnemu i ciężkiemu niedoborowi witaminy D. Do ustalenia lokalnych punktów odcięcia dla niedoborów witaminy D użyto krzywych ROC. Wyniki: U 3% dzieci stężenie witaminy 25-OHD wynosiło < 20 ng/ml, a u 26% wynosiło < 33 ng/ml (lokalny punkt odcięcia dla niedoboru witaminy D). Czas ekspozycji na słońce i dzienne spożycie witaminy D w diecie miały istotny wpływ na stężenie witaminy D w surowicy. Wnioski: W omawianym badaniu wykazano częste występowanie niedoboru witaminy D u dzieci zamieszkałych w Isfahanie. Wydłużenie czasu ekspozycji na słońce i zwiększenie dziennego spożycia witaminy D w diecie może zapobiec niedoborom witaminy D u tych dzieci. (Endokrynol Pol 2010; 61 (4): 377-382)Introduction: Vitamin D is essential for the maintenance of good health, and vitamin D deficiency has been reported from many countries, including those with a lot of sunshine. This study was conducted to evaluate the vitamin D status in healthy 6- to 7-year-old children in Isfahan, Iran. Material and methods: Five hundred and thirteen healthy children were enrolled. Serum PTH and 25-hydroxyvitamin D (25-OHD) were measured. Dietary vitamin D intake, duration of daily sunlight exposure, and percentage of exposed body surface area were determined. 25-OHD levels < 20 ng/mL and < 10 ng/mL were defined as mild and severe vitamin D deficiency, respectively. The ROC curve was utilized to obtain a local cut-off point of vitamin D deficiency. Results: 25-OHD was < 20 ng/mL in 3% and < 33 ng/mL (local cut-off point of vitamin D deficiency) in 26% of subjects. Duration of sunlight exposure and daily intake of vitamin D had significant effects on serum level of vitamin D. Conclusions: A high prevalence of vitamin D deficiency in Isfahan children was observed in this study. Improvements in duration of sunlight exposure and daily intake of vitamin D can prevent vitamin D deficiency in these children. (Pol J Endocrinol 2010; 61 (4): 377-382

    Effects of Pulsation to the Mean Field and Vortex Development in a Backward-Facing Step Flow

    Get PDF
    This work is concerned with the behavior of pulsatile flows over a backward-facing step geometry. The paper mainly focuses on the effects of the pulsation frequency on the vortex development of a 2:1 backward-facing step for mean Reynolds number of 100 and for 0.035 St 2.19. The dependence of the flow field on the Reynolds number (Re ¼ 100 and 200) was also examined for a constant Strouhal number, St of 1. A literature survey was carried out and it was found that the pulsation modifies the behavior of the flow pattern compared to the steady flow. It was shown in the present work that the inlet pulsation generally leads to differences in the mean flow compared to the steady field although the inlet bulk velocity is the same due to energy redistribution of the large-scale vortices, which result in nonlinear effects. The particle-image velocimetry results show that the formation of coherent structures, dynamical shedding, and transport procedure are very sensitive to the level of pulsation frequencies. For low and moderate inlet frequencies, 0.4 St 1, strong vortices are formed and these vortices are periodically advected downstream in an alternate pattern. For very low inlet frequency, St ¼ 0.035, stronger vortices are generated due to an extended formation time, however, the slow formation process causes the forming vortices to decay before shedding can happen. For high inlet frequencies, St ! 2.19, primary vortex is weak while no secondary vortex is formed. Flow downstream of the expansion recovers quickly. For Re ¼ 200, the pattern of vortex formation is similar to Re ¼ 100. However, the primary and secondary vortices decay more slowly and the vortices remain stronger for Re ¼ 200. The strength and structure of the vortical regions depends highly on St, but Re effects are not negligible

    Methicillin resistant Staphylococcus aureus adhesion to human umbilical vein endothelial cells demonstrates wall shear stress dependent behaviour

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) is an increasingly prevalent pathogen capable of causing severe vascular infections. The goal of this work was to investigate the role of shear stress in early adhesion events.</p> <p>Methods</p> <p>Human umbilical vein endothelial cells (HUVEC) were exposed to MRSA for 15-60 minutes and shear stresses of 0-1.2 Pa in a parallel plate flow chamber system. Confocal microscopy stacks were captured and analyzed to assess the number of MRSA. Flow chamber parameters were validated using micro-particle image velocimetry (PIV) and computational fluid dynamics modelling (CFD).</p> <p>Results</p> <p>Under static conditions, MRSA adhered to, and were internalized by, more than 80% of HUVEC at 15 minutes, and almost 100% of the cells at 1 hour. At 30 minutes, there was no change in the percent HUVEC infected between static and low flow (0.24 Pa), but a 15% decrease was seen at 1.2 Pa. The average number of MRSA per HUVEC decreased 22% between static and 0.24 Pa, and 37% between 0.24 Pa and 1.2 Pa. However, when corrected for changes in bacterial concentration near the surface due to flow, bacteria per area was shown to increase at 0.24 Pa compared to static, with a subsequent decline at 1.2 Pa.</p> <p>Conclusions</p> <p>This study demonstrates that MRSA adhesion to endothelial cells is strongly influenced by flow conditions and time, and that MSRA adhere in greater numbers to regions of low shear stress. These areas are common in arterial bifurcations, locations also susceptible to generation of atherosclerosis.</p

    A pulsatile flow system to engineer aneurysm and atherosclerosis mimetic extracellular matrix

    Full text link
    Alterations of blood flow patterns strongly correlate with arterial wall diseases such as atherosclerosis and aneurysm. Here, a simple, pumpless, close-loop, easy-to-replicate, and miniaturized flow device is introduced to concurrently expose 3D engineered vascular smooth muscle tissues to high-velocity pulsatile flow versus low-velocity disturbed flow conditions. Two flow regimes are distinguished, one that promotes elastin and impairs collagen I assembly, while the other impairs elastin and promotes collagen assembly. This latter extracellular matrix (ECM) composition shares characteristics with aneurysmal or atherosclerotic tissue phenotypes, thus recapitulating crucial hallmarks of flow-induced tissue morphogenesis in vessel walls. It is shown that the mRNA levels of ECM of collagens and elastin are not affected by the differential flow conditions. Instead, the differential gene expression of matrix metalloproteinase (MMP) and their inhibitors (TIMPs) is flow-dependent, and thus drives the alterations in ECM composition. In further support, treatment with doxycycline, an MMP inhibitor and a clinically used drug to treat vascular diseases, halts the effect of low-velocity flow on the ECM remodeling. This illustrates how the platform can be exploited for drug efficacy studies by providing crucial mechanistic insights into how different therapeutic interventions may affect tissue growth and ECM assembly

    The global, regional, and national burden of adult lip, oral, and pharyngeal cancer in 204 countries and territories:A systematic analysis for the Global Burden of Disease Study 2019

    Get PDF
    Importance Lip, oral, and pharyngeal cancers are important contributors to cancer burden worldwide, and a comprehensive evaluation of their burden globally, regionally, and nationally is crucial for effective policy planning.Objective To analyze the total and risk-attributable burden of lip and oral cavity cancer (LOC) and other pharyngeal cancer (OPC) for 204 countries and territories and by Socio-demographic Index (SDI) using 2019 Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study estimates.Evidence Review The incidence, mortality, and disability-adjusted life years (DALYs) due to LOC and OPC from 1990 to 2019 were estimated using GBD 2019 methods. The GBD 2019 comparative risk assessment framework was used to estimate the proportion of deaths and DALYs for LOC and OPC attributable to smoking, tobacco, and alcohol consumption in 2019.Findings In 2019, 370 000 (95% uncertainty interval [UI], 338 000-401 000) cases and 199 000 (95% UI, 181 000-217 000) deaths for LOC and 167 000 (95% UI, 153 000-180 000) cases and 114 000 (95% UI, 103 000-126 000) deaths for OPC were estimated to occur globally, contributing 5.5 million (95% UI, 5.0-6.0 million) and 3.2 million (95% UI, 2.9-3.6 million) DALYs, respectively. From 1990 to 2019, low-middle and low SDI regions consistently showed the highest age-standardized mortality rates due to LOC and OPC, while the high SDI strata exhibited age-standardized incidence rates decreasing for LOC and increasing for OPC. Globally in 2019, smoking had the greatest contribution to risk-attributable OPC deaths for both sexes (55.8% [95% UI, 49.2%-62.0%] of all OPC deaths in male individuals and 17.4% [95% UI, 13.8%-21.2%] of all OPC deaths in female individuals). Smoking and alcohol both contributed to substantial LOC deaths globally among male individuals (42.3% [95% UI, 35.2%-48.6%] and 40.2% [95% UI, 33.3%-46.8%] of all risk-attributable cancer deaths, respectively), while chewing tobacco contributed to the greatest attributable LOC deaths among female individuals (27.6% [95% UI, 21.5%-33.8%]), driven by high risk-attributable burden in South and Southeast Asia.Conclusions and Relevance In this systematic analysis, disparities in LOC and OPC burden existed across the SDI spectrum, and a considerable percentage of burden was attributable to tobacco and alcohol use. These estimates can contribute to an understanding of the distribution and disparities in LOC and OPC burden globally and support cancer control planning efforts

    Global, regional, and national burden of colorectal cancer and its risk factors, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

    Get PDF
    Funding: F Carvalho and E Fernandes acknowledge support from Fundação para a Ciência e a Tecnologia, I.P. (FCT), in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy i4HB; FCT/MCTES through the project UIDB/50006/2020. J Conde acknowledges the European Research Council Starting Grant (ERC-StG-2019-848325). V M Costa acknowledges the grant SFRH/BHD/110001/2015, received by Portuguese national funds through Fundação para a Ciência e Tecnologia (FCT), IP, under the Norma Transitória DL57/2016/CP1334/CT0006.proofepub_ahead_of_prin

    Effects of vitamin D supplementation on insulin resistance and cardiometabolic risk factors in children with metabolic syndrome: a triple-masked controlled trial

    Get PDF
    OBJECTIVE: this triple-masked controlled trial aimed to assess the effects of vitamin D supplementation on insulin resistance and cardiometabolic risk factors in obese children and adolescents. METHODS: the study comprised 50 participants, aged 10 to16 years, who were randomly assigned into two groups of equal number. In this 12-week trial, one group received oral vitamin D (300,000 IU) and the other group received placebo. Cardiometabolic risk factors, insulin resistance, and a continuous value of metabolic syndrome (cMetS) were determined. Statistical analysis was conducted after adjustment for covariate interactions. RESULTS: overall, 21 patients in the vitamin D group and 22 in the placebo group completed the trial. No significant difference was observed in the baseline characteristics of the two groups. After the trial, in the vitamin D group, serum insulin and triglyceride concentrations, as well as HOM -IR and C-MetS decreased significantly, both when compared with the baseline and with the placebo group. No significant difference was observed when comparing total cholesterol, LDL-C, HDL-C, fasting blood glucose, and blood pressure. CONCLUSION: the present findings support the favorable effects of vitamin D supplementation on reducing insulin resistance and cardiometabolic risk factors in obese children

    Torsion of epididymal Cyst as a cause of acute Scrotum in a child

    No full text
    Epididymal cyst is commonly seen in adults and sometimes in children. In most cases of the epididymal cyst, there are no symptoms and the diagnosis is made incidentally during ultrasonography. However, in rare circumstances, such as infection, trauma, or torsion, an epididymal cyst could become painful and require surgical or medical intervention. We report the case of an 11-year-old boy admitted to our hospital with acute right scrotal pain and treated surgically for epidydimal cyst torsion. Torsed epididymal cysts may cause symptoms exactly like testicular torsion. Therefore, It should be considered a differential diagnosis of testicular torsion in pediatrics
    corecore