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921.
Mercury is a toxic, environmentally heavy metal that can cause severe damage to all organs, including the nervous system. The functions of puerarin include antioxidant, anti-inflammatory, nerve cell repair, regulation of autophagy, and so forth. But because of the limited oral absorption of puerarin, it affects the protective effect on brain tissue. The nano-encapsulation of Pue can improve its limitation. Therefore, this study investigated the protective effect of Pue drug-loaded PLGA nanoparticles (Pue-PLGA-nps) on brain injury induced by mercuric chloride (HgCl2) in mice. The mice were divided into normal saline (NS) group, HgCl2 (4 mg/kg) group, Pue-PLGA-nps (50 mg/kg) group, HgCl2 + Pue (4 mg/kg + 30 mg/kg) group, and HgCl2 + Pue-PLGA-nps (4 mg/kg + 50 mg/kg) group. After 28 days of treatment, the mice were observed for behavioral changes, antioxidant capacity, autophagy and inflammatory response, and mercury levels in the brain, blood, and urine were measured. The results showed that HgCl2 toxicity caused learning and memory dysfunction in mice, increased mercury content in brain and blood, and increased serum levels of interleukin (IL-6), IL-1β, and tumor necrosis factor-α in the mice. HgCl2 exposure decreased the activity of T-AOC, superoxide dismutase, and glutathione peroxidase, and increased the expression of malondialdehyde in the brain of mice. Moreover, the expression levels of TRIM32, toll-like receptor 4 (TLR4), and LC3 proteins were upregulated. Both Pue and Pue-PLGA-nps interventions mitigated the changes caused by HgCl2 exposure, and Pue-PLGA-nps further enhanced this effect. Our results suggest that Pue-PLGA-nps can ameliorate HgCl2-induced brain injury and reduce Hg accumulation, which is associated with inhibition of oxidative stress, inflammatory response, and TLR4/TRIM32/LC3 signaling pathway.  相似文献   
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Background

Aortocaval fistula (AV) in rat is a unique model of volume-overload congestive heart failure and cardiac hypertrophy. Living donor kidney transplantation is regarded as beneficial to allograft recipients and not particularly detrimental to the donors. Impact of AV on animals with mild renal dysfunction is not fully understood. In this study, we explored the effects of AV in unilateral nephrectomized (UNX) rats.

Methods

Adult male Sprague-Dawley (SD) rats were divided into Sham (n = 10), UNX (right kidney remove, n = 10), AV (AV established between the levels of renal arteries and iliac bifurcation, n = 18) and UNX+AV (AV at one week after UNX, n = 22), respectively. Renal outcome was measured by glomerular filtration rate, effective renal plasma flow, fractional excretion of sodium, albuminuria, plasma creatinine, and cystatin C. Focal glomerulosclerosis (FGS) incidence was evaluated by renal histology. Cardiac function was measured by echocardiography and hemodynamic measurements.

Results

UNX alone induced compensatory left kidney enlargement, increased plasma creatinine and cystatin C levels, and slightly reduced glomerular filtration rate and increased FGS. AV induced significant cardiac enlargement and hypertrophy and reduced cardiac function and increased FGS, these changes were aggravated in UNX+AV rats.

Conclusions

Although UNX only induces minor renal dysfunction, additional chronic volume overload placement during the adaptation phase of the remaining kidney is associated with aggravated cardiac dysfunction and remodeling in UNX rats, suggesting special medical care is required for UNX or congenital monokidney subjects in case of chronic volume overload as in the case of pregnancy and hyperthyroidism to prevent further adverse cardiorenal events in these individuals.  相似文献   
926.
正DEAR EDITOR,Genetically improved farmed tilapia (GIFT) and GIFT-derived strains account for the majority of farmed tilapia worldwide. As male tilapias grow much faster than females, they are often considered more desirable in the aquacultural industry. Sex reversal of females to males using the male sex hormone17-α-methyltestosterone (MT) is generally used to induce phenotypic males during large-scale production of all male fingerlings. However, the widespread use of large quantities  相似文献   
927.
Journal of Plant Growth Regulation - Constituting the last stage of leaf development, leaf senescence is a complicated process that involves many senescence-associated genes, and numerous factors...  相似文献   
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Melanin concentrating hormone (MCH) plays an important role in the regulation of food intake and energy balance in mammals. MCH-1 receptor (MCH1R) deficient mice are lean and resistant to diet-induced obesity. As such, MCH1R antagonists are believed to have potential as possible treatments for obesity. The discovery of a novel class of tetralin ureas as potent MCH1R antagonists is described herein.  相似文献   
929.
In the course of an automated screening for small molecules presenting cytotoxic activity, eight new cyclophanes named kermadecins A-H (1-8), have been isolated from the bark of a New Caledonian plant, Kermadecia elliptica, Proteaceae. A LC/APCI-MS study performed on kermadecins A, B and C, provided a reliable method for the detection of other analogues existing in small quantities in the extract. This led to the isolation of five other members of this chemical series. The structures were elucidated by extensive mono- and bi-dimensional spectroscopy and mass spectrometry. The cytotoxic activity of four of them was evaluated on various cell lines.  相似文献   
930.
Valle LG  White MM  Cafaro MJ 《Mycologia》2008,100(1):149-162
This is the first report of Harpellales (Zygomycota) from Mexico, including herein only the endosymbiotic species of gut fungi in the digestive tracts or shed exuviae of Plecopteran and Ephemeropteran nymphs. Four new species are described: Allantomyces zopilotei, Bojamyces olmecensis, Gauthier-omyces viviparus and Graminella ophiuroidea. Among previously known Harpellales, Lancisporomyces nemouridarum and Zygopolaris ephemeridarum are southern range extremes and new records for Mexico. All species are illustrated and discussed relating to biogeographic implications of the new reports from Mexico, as well as the particular environmental circumstances of the Harpellales in the tropics.  相似文献   
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