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1.
There is a complex association among genetic, metabolic, and environmental factors in determining the risk of metabolic syndrome (MetS). The aim of this study was to investigate the role of the association between the dietary intake of iron, copper, zinc, manganese, selenium, and iodine (assessed by 24 recall) with vascular endothelial growth factor variants (rs6921438, rs4416670, rs6993770, and rs10738760), on the risk of MetS. Two-hundred and forty-eight individuals with MetS and 100 individuals without MetS were recruited. The dietary intake and the daily average of energy and nutrient intake were obtained by a questionnaire and quantified using Diet Plan 6 software. DNA was extracted from EDTA anticoagulated whole blood. The SNPs were assessed using using a Sequenom iPLEX Gold assay. Data analysis was undertaken using the Student t test, χ2 test and logistic regression using SPSS 11.5 software. There was a significant association between low dietary iron intake and rs6993770 (β = .10, P < .05), and a low dietary zinc and a high manganese intake with rs6921438 in relation to the presence of MetS (β = −.17, P < .05, β = −.30, P < .05, respectively). Our data showed the association of rs6993770 with iron intake and rs6921438 with zinc and manganese intake, indicating further investigation in a larger population to evaluate their values.  相似文献   
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Spermatogonial cells (SCs) are key cells for spermatogenesis. These cells are affected by paracrine signals originated from nearby somatic cells, among them Leydig cells have receptors for osteocalcin, a hormone known for exerting positive roles in the promotion of spermatogenesis. The aim of this study was to evaluate roles for osteocalcin on SCs proliferative and differentiation features after coculture with Leydig cells. SCs and Leydig cells were isolated from neonate NMRI offspring mice and adult NMRI mice, respectively. SCs population were then enriched in a differential attachment technique and assessed for morphological features and identity. Then, SCs were cocultured with Leydig cells and incubated with osteocalcin for 4 weeks. Evaluation of proliferation and differentiation-related factors were surveyed using immunocytochemistry (ICC), Western blot, and quantitative real-time polymerase chain reaction (PCR). Finally, the rate of testosterone release to the culture media was measured at the end of 4th week. Morphological and flow cytometry results showed that the SCs were the population of cells able to form colonies and to express ID4, α6-, and β1-integrin markers, respectively. Leydig cells were also able to express Gprc6α as a specific marker for the cells. Incubation of SCs/Leydig coculture with osteocalcin has resulted in an increase in the rate of expressions for differentiation-related markers. Levels of testosterone in the culture media of SCs/Leydig was positively influenced by osteocalcin. It could be concluded that osteocalcin acts as a positive inducer of SCs in coculture with Leydig cells probably through stimulation of testosterone release from Leydig cells and associated signaling.  相似文献   
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In this research, kinetics of Cr(VI) reduction by iron filings was investigated through a batch study in seven different soils. Chromate reduction experiments were carried out for initial Cr(VI) concentrations ranging from 20 to 100 mgkg?1 and iron filings dosage of 0 to 5% w/w. The experimental data were analyzed using various kinetic models including zero-order, pseudo first-order, power function, Elovich, and diffusion parabolic. Results showed that the Cr(VI) reduction efficiency in the presence of all studied soils increased with increasing iron filings dosage and decreased with increasing the initial Cr(VI) concentration. The reaction rates considerably depended on pH and were higher in acidic soils. The diffusion parabolic model was the best kinetic model as evidenced by the highest determination coefficient (r2) and the lowest standard error of the estimate (SE). The rate-limiting step(s) may be transport of chromate anions across a liquid film at the interface of soil-liquid, transport in liquid-filled macropores of iron filings aggregates, or diffusion in micropores and along the particle's surface.  相似文献   
5.

Purpose

The MUYU Collaboration is a partnership between Mulago Hospital-Makerere University College of Health Sciences (M-MakCHS), in Kampala, Uganda, and the Yale University School of Medicine. The program allows Ugandan junior faculty to receive up to 1 year of subspecialty training within the Yale hospital system. The authors performed a qualitative study to assess the effects of this program on participants, as well as on M-MakCHS as an institution.

Methods

Data was collected via semi-structured interviews with exchange participants. Eight participants (67% of those eligible as of 4/2012) completed interviews. Study authors performed data analysis using standard qualitative data analysis techniques.

Results

Analysis revealed themes addressing the benefits, difficulties, and opportunities for improvement of the program. Interviewees described the main benefit of the program as its effect on their fund of knowledge. Participants also described positive effects on their clinical practice and on medical education at M-MakCHS. Most respondents cited financial issues as the primary difficulty of participation. Post-participation difficulties included resource limitations and confronting longstanding institutional and cultural habits. Suggestions for programmatic improvement included expansion of the program, ensuring appropriate management of pre-departure expectations, and refinement of program mentoring structures. Participants also voiced interest in expanding post-exchange programming to ensure both the use of and the maintenance of new capacity.

Conclusions

The MUYU Collaboration has benefitted both program participants and M-MakCHS, though these benefits remain difficult to quantify. This study supports the assertion that resource-poor to resource-rich exchanges have the potential to provide significant benefits to the resource-poor partner.  相似文献   
6.
Genetic and environmental factors are important for the development of nonalcoholic fatty liver disease (NAFLD). The aim of the present study was to examine the single nucleotide polymorphism (SNP) -129C/T (rs17883901) in glutamate-cysteine ligase catalytic subunit (GCLC) and SNPs I128T (rs3816873) and Q95H (rs61733139) in microsomal triglyceride transfer protein (MTTP) in NAFLD. Eighty-three patients with a diagnosis of NAFLD and 93 healthy subjects were included in the study. Tetra amplification refractory mutation system-polymerase chain reaction was designed to detect the SNPs. There were no significant differences in the polymorphism of -129C/T (rs17883901) of the GCLC gene among NAFLD and control groups (p?>?0.05). A significant difference was observed between NAFLD and control group regarding the SNP I128T (rs3816873) in the coding region of the MTTP gene (p?相似文献   
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This study investigates the modification of UV-A radiation for enhancing the growth rate of Synechococcus species in a simulated photobioreactor made of UV-stabilized polycarbonate (PC) plates. Uvitex OB as was dissolved in a poly(methyl methacrylate) (PMMA)-based resin and the mixture was applied as a coating to shift the UV-A radiation to photosynthetically active radiation (PAR). The feasibility of applying the Uvitex OB in a PMMA-based resin, which was used as fluorescent layer to shift UV-A to PAR range, was explored. For this purpose, a variety of concentrations of Uvitex OB in resin were prepared and coated on PC sheets which were placed between the radiation source and the culture flask. Compared to the uncoated PC sheet, the PC panels coated with a few number of the wavelength shifter layer caused an approximately 4-fold increase in cell number during the same culture period.  相似文献   
10.
The existence of long-lasting (15–18 h) alterations of neurotrasmitter amino acid levels following a single or repeated acoustic stimulations in audiogenic seizure-prone Rb1 and Rb2 mice and suizure-resistant Rb3 mice were investigated. The levels of glutamate, aspartate, glycine, taurine, and of some of their precursors: glutamine and serine were determined. Fourteen brain areas were examined. Alterations were found only in 6 brain areas (pons, olfactory bulbs, superior colliculus, inferior colliculus, olfactory tubercles and raphe). Most frequent occuring changes were observed in pons and olfactory tubercles. These changes concerned mainly the excitatory amino acids, glutamate, and aspartate. Alterations of taurine, glycine and serine were also recorded.Abbreviations GABA 4-aminobutyrate - Tau taurine - Gly glycine - Asp aspertate - Glu glutamate - Gln glutamine - Ser serine - OB olfactory bulbs - OT olfactory tubercles - Sr striatum - Se septum - Hy hypothalamus - Th thalamus - Hi hippocampus - A amygdala - SC superior colliculus - IC inferior colliculus - FC frontal cortex - C cerebellum - P pons medulla - Ra raphe - AA neurotransmitter amino acids - I inhibitory - E excitatory - SSL steady-state level Plesant memories of Lawrence Austin's sojourn in my group at Strasbourg gather upon me when I dedicate this article on this occasion for the contribution that Lawrence Austin has made for the cause of neurochemical researchers.  相似文献   
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