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排序方式: 共有202条查询结果,搜索用时 15 毫秒
1.
Doxorubicin (DOX) is an anthracycline drug used for cancer treatment. However, its treatment is contiguous with toxic effects. We examined the nephroprotective potential of A. hydaspica polyphenol-rich ethyl acetate extract (AHE) against DOX persuaded nephrotoxicity. 36 male Sprague Dawley rats were randomly assorted into 6 groups. Control group received saline; DOX group: 3 mg/kg b.w. dosage of DOX intraperitoneally for 6 weeks (single dose/week). In co-treatment groups, 200 and 400 mg/kg b.w AHE was given orally for 6 weeks in concomitant with DOX (3 mg/kg b.w, i.p. injection per week) respectively. Standard group received silymarin 400 mg/kg b.w daily + DOX (single dose/week). Biochemical kidney function tests, oxidative stress markers, genotoxicity, antioxidant enzyme status, and histopathological changes were examined. DOX caused significant body weight loss and decrease kidney weight. DOX-induced marked deterioration in renal function indicators in both urine and serum, i.e., PH, specific gravity, total protein, albumin, urea, creatinine, uric acid, globulin, blood urea nitrogen, etc. Also, DOX treatment increases renal tissue oxidative stress markers, while lower antioxidant enzymes in tissue along with degenerative alterations in the renal tissue compared to control rats. AHE co-treatment ameliorates DOX-prompted changes in serum and urine chemistry. Likewise, AHE treatment decreases sensitive markers of oxidative stress and prevented DNA damages by enhancing antioxidant enzyme levels. DOX induction in rats also caused DNA fragmentation which was restored by AHE co-treatment. Moreover, the histological observations evidenced that AHE effectively rescued the kidney tissue from DOX interceded oxidative damage. Our results suggest that co-treatment of AHE markedly improve DOX-induced deleterious effects in a dose-dependent manner. The potency of AHE co-treatment at 400 mg/kg dose is similar to silymarin. These outcomes revealed that A. hydaspica AHE extract might serve as a potential adjuvant that avoids DOX-induced nephrotoxicity.  相似文献   
2.
《Fungal biology》2020,124(1):44-53
Alternaria blight is one of the most devastating diseases of rapeseed-mustard caused by a necrotrophic fungus Alternaria brassicae. Lack of satisfactory resistance resource in Brassica is still a main obstruction for developing resistance against Alternaria. In this study, we have selected Brassica juncea, Sinapis alba and Camelina sativa to understand and unravel the mechanism of disease resistance against Alternaria. Histopathological studies showed early onset of necrosis in B. juncea (1 dpi) and delayed in S. alba (2 dpi) and C. sativa (3 dpi) respectively. Early and enhanced production of hydrogen peroxide (H2O2) was observed in C. sativa and S. alba (6 hpi) when compared to B. juncea (12 hpi). An increase in catalase activity was observed in both C. sativa (36 % at 6 hpi) and S. alba (15 % at 12 hpi), whereas it significantly decreased in B. juncea at 6 hpi (23 %), 12 hpi (30 %) and 24 hpi (8 %). Gene expression analysis showed induction of PR-3 and PR-12 genes only in C. sativa and S. alba when compared to B. juncea suggesting their vital role for Alternaria resistance. In contrast, SA marker genes were significantly expressed in B. juncea only which provides evidence of hormonal cross talk in B. juncea during Alternaria infection thereby increasing its susceptibility.  相似文献   
3.
微囊藻细胞抽提液对小鼠血液的亚慢性毒性   总被引:1,自引:1,他引:0  
本文研究了注射含微囊藻毒素的微囊藻细胞抽提掖对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8 和 9.6 μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d 染毒后,小鼠的肝体比和脾体比都明显增大(p < 0.05), 同时在9.6 μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6 μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。  相似文献   
4.
In this research, we characterized the histopathological impact of dengue virus (serotype DENV-2) infection in livers of BALB/c mice. The mice were infected with different doses of DENV-2 via intraperitoneal injection and liver tissues were processed for histological analyses and variation was documented. In the BALB/c mouse model, typical liver tissues showed regular hepatocyte architecture, with normal endothelial cells surrounding sinusoid capillary. Based on histopathological observations, the liver sections of BALB/c mice infected by DENV-2 exhibited a loss of cell integrity, with a widening of the sinusoidal spaces. There were marked increases in the infiltration of mononuclear cells. The areas of hemorrhage and micro- and macrovesicular steatosis were noted. Necrosis and apoptosis were abundantly present. The hallmark of viral infection, i.e., cytopathic effects, included intracellular edema and vacuole formation, cumulatively led to sinusoidal and lobular collapse in the liver. The histopathological studies on autopsy specimens of fatal human DENV cases are important to shed light on tissue damage for preventive and treatment modalities, in order to manage future DENV infections. In this framework, the method present here on BALB/c mouse model may be used to study not only the effects of infections by other DENV serotypes, but also to investigate the effects of novel drugs, such as recently developed nano-formulations, and the relative recovery ability with intact immune functions of host.  相似文献   
5.
Schistosomiasis is still one of the main parasitic diseases that affect human health in tropical regions. Whilst praziquantel (PZQ) is the main classic antischistosomal drug, the need for new drugs is still a must due to the low effectiveness of the drug on the schistosome young worms, and the evolving of PZQ resistant strains. Nanotechnology is one of the most important recent and current methods used to treat human diseases including parasitic ones. Therefore, the present study aimed to examine the curative role of gold nanoparticles (GNPs) on splenic tissue of mice infected with Schistosoma mansoni Sambon, 1907. High-resolution transmission electron microscopy was used for characterization of nanoparticles (NP). GNPs of 1 mg/kg mice body weight were inoculated into mice infected with S. mansoni. The parasite caused deteriorations in histological architecture of the spleen tissue, and splenomegaly. Additionally, the parasite induced a significant reduction in splenic tissue glutathione levels; however, the concentrations of nitric oxide and malondialdehyde were significantly increased. Treatment of mice with GNPs reduced the extent of histological impairment and oxidative stress in spleen tissue. Therefore, our results demonstrate the protective role of GNPs against splenic damage in mice infected with S. mansoni.  相似文献   
6.
7.
Mussels (Mytilus edulis) were exposed to cultures of the toxic dinoflagellate Alexandrium fundyense or the non-toxic alga Rhodomonas sp. to evaluate the effects of the harmful alga on the mussels and to study recovery after discontinuation of the A. fundyense exposure. Mussels were exposed for 9 days to the different algae and then all were fed Rhodomonas sp. for 6 more days. Samples of hemolymph for hemocyte analyses and tissues for histology were collected before the exposure and periodically during exposure and recovery periods.Mussels filtered and ingested both microalgal cultures, producing fecal pellets containing degraded, partially degraded, and intact cells of both algae. Mussels exposed to A. fundyense had an inflammatory response consisting of degranulation and diapedesis of hemocytes into the alimentary canal and, as the exposure continued, hemocyte migration into the connective tissue between the gonadal follicles. Evidence of lipid peroxidation, similar to the detoxification pathway described for various xenobiotics, was found; insoluble lipofuchsin granules formed (ceroidosis), and hemocytes carried the granules to the alimentary canal, thus eliminating putative dinoflagellate toxins in feces. As the number of circulating hemocytes in A. fundyense-exposed mussels became depleted, mussels were immunocompromised, and pathological changes followed, i.e., increased prevalences of ceroidosis and trematodes after 9 days of exposure. Moreover, the total number of pathological changes increased from the beginning of the exposure until the last day (day 9). After 6 days of the exposure, mussels in one of the three tanks exposed to A. fundyense mass spawned; these mussels showed more severe effects of the toxic algae than non-spawning mussels exposed to A. fundyense.No significant differences were found between the two treatments during the recovery period, indicating rapid homeostatic processes in tissues and circulating hemocytes.  相似文献   
8.
The aim of this study is to determine the effects of magnetic field via cell phones on some blood parameters and neurons in the brain of rats. Animals have been classified into three groups: control, Magnetic Field (MF), and F2 groups. Throughout this study, cell phones were placed on the wall of the cages. Rats were exposed to the effects of cell phones during prenatal and postnatal periods until they were 80 days old. During the study, the exposure procedure of rats was that the phone was in standby mode for a whole day and in talking mode for 30 min per day. The waves of cell phones caused an increased blood glucose level from 96.52 ± 5.64 mg/dl to 132.14 ± 5.93 mg/dl and an increased serum protein level from 131.14 ± 6.19 mg/dl to 319.29 ± 6.73 mg/dl compared to control. Statistically, significant differences wasn't observed in the blood cholesterol concentration between the groups compared to the control. Weekly weight gain decreased in all groups compared to the control. MF exposure decreased pyramidal neuron numbers 51.15% and increased ischemic neuron numbers 73% at cortex region of brain. In addition, vascular dilatations have increased clearly in group F2.Whereas the procedure of MF did not have any effects on hippocampal pyramidal cell numbers, magnetic fields increased the amount of ischemic neurons three-fold compared to the control. In conclusion, MF affected some biochemical parameters, especially the cortex region of the brain.  相似文献   
9.
A study of neurological diseases in farmed deer, with emphasis on chronic wasting disease, was conducted during 2 years in Switzerland. Deer breeders were asked to submit the heads of all deer at least 2 years of age, found dead or slaughtered, for examination. A complete histological examination of the brain and immunohistochemical detection of the prion protein on selected regions of the brain and lymphoid tissues were performed on 120 apparently healthy and 40 diseased animals. In a number of cases, a full necropsy was performed. Significant inflammatory and/or degenerative changes were seen in 25% of the brains. No evidence for a transmissible spongiform encephalopathy was established.  相似文献   
10.
目的探讨大剂量电离辐射对小鼠肺的影响。方法 60Coγ照射小鼠,HE染色观察小鼠肺组织损伤,免疫组化检测小鼠肺转化生长因子β1(TGFβ1)和细胞间粘附因子1(ICAM1)的表达。结果大剂量照射后3d,小鼠肺发生明显异常病变,TGFβ1和ICAM1表达量明显增加。结论肺内皮细胞损伤和血管内物质外漏可能是急性放射性肺损伤的早期重要事件,早期检测ICAM1有助于预测急性放射性肺损伤的发生程度。  相似文献   
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