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61.
International Journal of Diabetes in Developing Countries - This study was aimed at determining the levels of serum zonulin during the first trimester in pregnant women and to examine the...  相似文献   
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Human exposure to sodium fluoride through its daily usage is almost inevitable. Cardiovascular and renal dysfunction has been associated with fluoride toxicity. Therefore, this study investigated the mechanism of action of sodium fluoride (NaF) induced hypertension and cardiovascular complications Forty male albino rats of an average of 10 rats per group were used. Group A received clean tap water. Toxicity was induced in Group B to D by administering graded doses of NaF through drinking water ad libitum for 10 days at 150 ppm, 300 ppm, and 600 ppm concentration respectively. Following administration of NaF, there was significant increase in systolic pressure, diastolic pressure and mean arterial pressure. Markers of oxidative stress; malondialdehyde, hydrogen peroxide, advance oxidation protein products, and protein carbonyl were significantly increased in dose‐dependent pattern in the cardiac and renal tissues of rats together with significant decrease in the GST activity in NaF‐treated rats compared to the control. Also serum markers of inflammation, cardiac, and renal damage including myeloperoxidase, xanthine oxidase, blood urea nitrogen, creatinine, Lactate dehydrogenase (LDH), and Creatinine kinase myocardial band (CK‐MB) significantly increased indicating induction of oxidative stress, renal, and cardiac damage after exposure. Histopathology of the kidney and heart revealed aberrations in the histological architecture in NaF‐treated rats. Also, immunohistochemistry showed higher expression of nuclear factor kappa beta (NF‐kB) in the cardiac and renal tissues of rats administered NaF. Combining all, these results indicate NaF‐induced hypertension through generation of reactive oxygen species and activation of renal and cardiac NF‐kB expressions. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1089–1101, 2017.  相似文献   
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This study is a systematic review and meta-analysis of studies using nucleic acid-based techniques to detect Mycobacterium avium paratuberculosis (MAP) in patients with Crohn's disease (CD) compared with controls. Database searches were conducted and risk difference estimates were calculated using meta-analysis. Fifty-eight studies were reviewed, 47 of which were included in the analysis. The pooled estimate of risk difference from all studies was 0.23 (95% confidence interval [CI], 0.14-0.32) using a random effects model. Similarly, MAP was detected more frequently from patients with CD compared with those with ulcerative colitis (risk difference 0.19, 95% CI, 0.10-0.28). Year of study, assay type, and inclusion of children explained some but not all of the observed heterogeneity. The data confirms the observation that MAP is detected more frequently among CD patients compared with controls. However, the pathogenic role of this bacterium in the gut remains uncertain. Our analysis demonstrates that there is an association between MAP and CD, across many sites, by many investigators, and controlling for a number of factors; however, this association remains controversial and inconclusive. Future studies should determine whether there is a pathogenic role.  相似文献   
65.
Uca tangeri is a marine fiddler crab found commonly in the West African coast and is often exposed to Gram-negative pathogens upon injury. The aim of this study was to document the patterns of endotoxin-induced protein coagulation and phenoloxidase (PO) activity in hemolymph fractions of Uca tangeri. Hemolymph from live crabs was obtained by carapace puncture, pooled. and then separated into plasma, hemocyte Lysate (HL), hemocyte lysate supernatant (HLS) and hemocyte lysate debris (HLD). The effect of Escherichia coli (O1111:B4) endotoxin and calcium ion (Ca2+) on protein coagulation in the presence/absence of endotoxin and the endotoxin dose-dependence of coagulation and PO activity were each studied in the plasma, HL, HLS and HLD. The results showed Ca2+ was required to induce coagulation, and was endotoxin concentration-dependent in the plasma. PO activity was highest in the HLS but PO specific activity was highest in HLD. PO activity remained relatively constant with increased LPS concentration in the range studied 0–10 EU/ml. From the data we conclude that endotoxin-induced protein coagulation occurs in the plasma alone and might be mediated by trans-glutaminases, while PO activity is localized inside hemocytes and cell membranes in Uca tangeri.  相似文献   
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Sex hormone‐dependent vascular reactivity is an underlying factor contributing to sex differences in salt‐dependent hypertension. This study evaluated the role of androgens (testosterone) in high salt‐induced increase in blood pressure (BP) and altered vascular reactivity in renal blood flow and perfused hind limb preparation. Weanling male rats (8 weeks old, 180–200 g) were bilaterally orchidectomised or sham operated with or without testosterone replacement (Sustanon 250, 10 mg/kg intramuscularly once in 3 weeks) and placed on a normal (0.3%) or high (4.0%) NaCl diet for 6 weeks. The high‐salt diet (HSD) increased arterial BP, renal vascular resistance (RVR) and positive fluid balance (FB). These changes were accompanied by decreased plasma nitric oxide levels. The increased BP, RVR and FB observed in the rats fed a HSD were reversed by orchidectomy while testosterone replacement prevented the reversal. Phenylephrine (PE)‐induced increased vascular resistance in the perfused hind limb vascular bed was enhanced by HSD, the enhanced vascular resistance was prevented by orchidectomy and testosterone replacement reversed orchidectomy effect. Vasorelaxation responses to acetylcholine (ACh) and sodium nitroprusside (SNP) were impaired in HSD groups, orchidectomy attenuated the impairment, while testosterone replacement prevented the orchidectomy attenuation. These data suggested that eNOS‐dependent and independently‐mediated pathways were equally affected by HSD in vascular function impairment and this effect is testosterone‐dependent in male Sprague‐Dawley rats.  相似文献   
67.
The aim of this study is to synthesize Titania nanotubes (TNTs) on the 3D-printed Ti-6Al-4V surface and investigate the loading of antibacterial vancomycin drug dose of 200 ppm for local drug treatment application for 24 h. The antibacterial drug release from synthesized nanotubes evaluated via the chemical surface measurement and the linear fitting of Korsmeyer–Peppas model was also assessed. The TNTs were synthesized on the Ti-6Al-4V surface through the anodization process at different anodization time. The TNTs morphology was characterized using field emission scanning electron microscope (FESEM). The wettability and the chemical composition of the Ti-6Al-4V surface and the TNTs were assessed using the contact angle meter, Fourier transform infrared spectrophotometer (FTIR) and the X-ray photoelectron spectroscopy (XPS). The vancomycin of 200 ppm release behavior under controlled atmosphere was measured by the high-performance liquid chromatography (HPLC) and hence, the position for retention time at 2.5 min was ascertained. The FESEM analysis confirmed the formation of nanostructured TNTs with vertically oriented, closely packed, smooth and unperforated walls. The maximum cumulative vancomycin release of 34.7% (69.5 ppm) was recorded at 24 h. The wetting angle of both Ti-6Al-4V implant and the TNTs were found below 90 degrees. This confirmed their excellent wettability.  相似文献   
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Several agro-waste materials have been utilized for sustainable engineering and environmental application over the past decades, showing different degrees of effectiveness. However, information concerning the wider use of palm oil clinker (POC) and its performance is still lacking. Therefore, as a solid waste byproduct produced in one of the oil palm processing stages, generating a huge quantity of waste mostly dumped into the landfill, the waste-to-resource potential of POC should be thoroughly discussed in a review. Thus, this paper provides a systematic review of the current research articles on the several advances made from 2005 to 2021 regarding palm oil clinker physical properties and performances, with a particular emphasis on their commitments to cost savings during environmental and engineering applications. The review begins by identifying the potential of POC application in conventional and geopolymer structural elements such as beams, slabs, and columns made of concrete, mortar, or paste for coarse aggregates, sand, and cement replacement. Aspects such as performance of POC in wastewater treatment processes, fine aggregate and cement replacement in asphaltic and bituminous mixtures during highway construction, a bio-filler in coatings for steel manufacturing processes, and a catalyst during energy generation are also discussed. This review further describes the effectiveness of POC in soil stabilization and the effect of POC pretreatment for performance enhancement. The present review can inspire researchers to find research gaps that will aid the sustainable use of agroindustry wastes. The fundamental knowledge contained in this review can also serve as a wake-up call for researchers that will motivate them to explore the high potential of utilizing POC for greater environmental benefits associated with less cost when compared with conventional materials.  相似文献   
70.
Kang D  Liao M  Jiang Z  Zhang X  Mao W  Zhang N  Tao X  Huang T  Bi Z  Aliyu M  Wu P  Jiang B  Jia Y 《AIDS care》2011,23(Z1):26-36
The objective of this study was to assess the factors associated with methamphetamine (MA) use, syphilis, and unprotected sex among female sex workers from different type of venues in Qingdao City, Shandong Province of China. Three consecutive cross-sectional surveys provided information on demographics, sexual and drug use behaviors, and HIV-related services. Of 1187 participants, 3.0% were infected with syphilis; 30.2% ever used MA; 58.3% ever had unprotected commercial sex in the past month. The prevalence rates of syphilis and MA use were 2.5% and 33.0% for participants recruited from saunas, night clubs, bars or hotels; 2.7% and 28.3% for hair/beauty salon-based participants; and 4.5% and 15.8% for street-based participants. Street-based MA users were more likely to be single, non-Shandong residents, have first lifetime sex act at younger age, and recruited in 2008 (vs. 2006). Saunas, night clubs, bars, or hotels-based MA users were more likely to be younger, sex debut at younger age, have longer duration of sex work, have unprotected commercial sex, and be syphilis-infected. Hair/beauty salon-based MA users were more likely to be non-Shandong residents, younger, and to have unprotected commercial sex. Syphilis among the sauna-, night club-, bar-, or hotel-based participants was associated with MA use and ever receipt of HIV testing. Syphilis among the hair/beauty salon-based participants was associated with longer duration of sex work. MA users who frequent commercial sex venues are engaging in high-risk behaviors and are at risk for syphilis/other sexually transmitted diseases. Better-targeted intervention efforts to curtail the epidemics of MA use and HIV/syphilis should therefore take cognizance of the role of commercial sex venues as focal points of MA use and syphilis/sexually transmitted disease transmission.  相似文献   
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