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131.
Acute monocytic leukemia is a type of myeloid leukemia that develops in monocytes. The current clinical therapies for leukemia are unsatisfactory due to their side effects and nonspecificity toward target cells. Some lectins display antitumor activity and may specifically recognize cancer cells by binding to carbohydrate structures on their surface. Therefore, this study evaluated the response of the human monocytic leukemia cell lines THP-1 to the Olneya tesota PF2 lectin. The induction of apoptosis and reactive oxygen species production in PF2-treated cells was evaluated by flow cytometry, and the lectin-THP-1 cell interaction and mitochondrial membrane potential were evaluated by confocal fluorescence microscopy. PF2 genotoxicity was evaluated by DNA fragmentation analysis via gel electrophoresis. The results showed that PF2 binds to THP-1 cells, triggers apoptosis and DNA degradation, changes the mitochondrial membrane potential, and increases reactive oxygen species levels in PF2-treated THP-1 cells. These results suggest the potential use of PF2 for developing alternative anticancer treatments with enhanced specificity.  相似文献   
132.
《Reproductive biology》2023,23(1):100724
Fluoride is a common environmental contaminant that has harmful effects on human health when it is present in high concentrations. Fluoride enters the bloodstream after being absorbed by the gastrointestinal system when fluoride-contaminated groundwater is consumed by people. The aim of the present study was to determine whether polyphenol-rich nano Moringa oleifera (NMO) could protect rat testicles from sodium fluoride (NaF) damage by evaluating sperm quality, sex hormones, testicular oxidative status, histopathology, and StAR gene expression. Twenty-eight adult Wistar rats were divided equally and randomly into four groups: group one received distilled water; group two received NMO at a dosage of 250 mg/kg/body weight; group three received NaF at a dosage of 10 mg/kg/body weight; and group four received NaF and NMO. The rats were orally administrated daily for a duration of eight weeks. The study's findings demonstrated that, in comparison to rats exposed to NaF alone, co-administration of NMO and NaF enhanced sperm motility and viability, decreased sperm morphological changes, restored the balance between oxidant and antioxidant status, improved testosterone and dehydroepiandrosterone, improved testicular histology, raised the Johnson score, and upregulated the StAR gene in testicular tissue. These findings show that NMO is promise as a prophylactic medication against sodium fluoride-induced testicular damage because administration of NMO had no adverse effects and enhanced reproductive health.  相似文献   
133.
摘要 目的:观察重症急性胰腺炎(SAP)合并腹腔感染(IAI)患者病原菌分布,分析药物敏感性,同时探讨其院内死亡的危险因素。方法:本研究纳入2017年1月~2022年1月期间来解放军联勤保障部队第九二二医院接受治疗并确诊的SAP合并IAI患者100例,采集患者腹水标本,观察其病原菌分布,分析药物敏感性。入院后收集患者人口学特征、实验室检查等资料,探讨患者院内死亡的危险因素。结果:100例SAP合并IAI患者腹水标本中,分离出186株病原菌,其中革兰阴性菌有108株,占比58.06%。革兰阳性菌51株,占比27.42%。真菌27株,占比14.52%。鲍曼不动杆菌对不同抗菌药物的敏感性均较低,大肠埃希菌对厄他培南、亚胺培南、哌拉西林/他唑巴坦、庆大霉素、美罗培南的敏感性较高,肺炎克雷伯菌对亚胺培南、美罗培南的敏感性较高,葡萄球菌属对替加环素、万古霉素、利奈唑胺的敏感性较高,屎肠球菌对替加环素、利奈唑胺的敏感性较高,粪肠球菌对氨苄西林、万古霉素、环丙沙星、替加环素的敏感性较高。单因素分析显示,SAP合并IAI患者院内死亡与器官障碍数目、膀胱压、入院时急性生理学与慢性健康状况评分(APACHE II)评分、白细胞计数(WBC)、血钙、红细胞压积(HCT)、总胆固醇(TC)、甘油三醋(TG)、降钙素原(PCT)、C反应蛋白(CRP)、动脉二氧化碳分压(PaCO2)、动脉氧分压(PaO2)有关(P<0.05)。多因素Logistic回归分析结果显示:器官障碍数目偏多、血钙偏低、CRP偏高、APACHE II评分偏高、膀胱压偏高、PaO2偏低、WBC偏高是导致SAP合并IAI患者院内死亡的危险因素(P<0.05)。结论:SAP合并IAI患者病原菌分布以革兰阴性菌为主,主要的革兰阴性菌、革兰阳性菌耐药率高。此外,器官障碍数目偏多、血钙偏低、CRP偏高、APACHE II评分偏高、膀胱压偏高、PaO2偏低、WBC偏高是影响SAP合并IAI患者院内死亡的危险因素。  相似文献   
134.
135.
Avoidance thresholds and 96-h LC50 values were determined for golden shiners, Noiemigonus crysoleucas , for five individual elements: chromium, Cr; copper, Cu; cadmium, Cd; arsenic, As; selenium, Se. The avoidance concentrations were 73, 26 and 28 μgl-1 for Cr-VI, Cu and As-III, respectively. Cadmium and Se were not avoided at experimental concentrations up to 68 and 3489 μg1-1, respectively. Acute flow-through 96-h LC50 values were Cr-VI 55·0, Cu 84·6, and As-III 12·5 mg 1-1, which were more than two orders of magnitude above avoidance concentrations. The acute flow-through 96-h LC50 values for Cd and Se were 2·8 and 11·2 mg 1-1, respectively. These concentrations are 31 and 2·2 times the highest concentration employed in the avoidance tests, neither of which were avoided by the test organisms. Thus, simple toxicity tests do not identify the environmental hazard of some elements, and the most toxic elements may not elicit a behavioural response. When used in concert with tests of organism function, more realistic indicators of environmental hazard or safety may be determined.  相似文献   
136.
The toxicity of a commercial formulation of the insecticide parathion‐methyl to the N2‐fixing filamentous cyanobacterium (blue‐green alga) Cylindrospermum, sp. was studied. A concentration of parathion‐methyl of 0.5 ppm caused growth increase in liquid growth media. The minimum inhibitory concentration of parathion‐methyl for both types (N2, fixing and nitrate supplemented) of liquid and solid media was 1.0 ppm. LC50 values were: 4.4 ppm (liquid, N2, fixing), 5.5 ppm (liquid, nitrate supplemented), 3.3 ppm (agar, N2‐fixing) and 4.0 ppm (agar, nitrate supplemented). LC100 values for N2‐fixing liquid and both types of agar media were 10.0 ppm, while for the liquid nitrate supplemented medium the LC100 was 12.0 ppm. Both akinete (spore) formation and germination were inhibited below the highest permissive concentration of 8.0 ppm, with the insecticide incorporated in the agar media. In soil, the LC50 and LC100 values for parathion‐methyl were 13.6 and 30 ppm, respectively. Both the dehydrogenase activity of heterocysts (monitored by 2,3,5‐triphenyl tetrazolium chloride reduction) and the nitrogen concentration of cultures (estimated by the micro‐Kjeldahl method) were affected by the insecticide, but the latter (N2‐fixation) was more sensitive. The Kruskal‐Wallis H test on the numbers of vegetative cells in the filaments revealed that the insecticide significantly affected the division of vegetative cells. The cyanobacterium could detoxify the growth medium containing high levels (30 and 40 ppm) of the insecticide in short‐term exposures at the expense of cell viability.  相似文献   
137.
The effects on mitochondrial respiratory parameters of heavy metals, such as Cu, Ni, Pb, Cd, Zn, Ag, Hg, were recorded by using thein vitro response of submitochondrial particles (SMP) from beef heart mitochondria.The toxicity of these elements was estimated by determining their effects on the energy-coupled reverse electron transfer (RET), which is induced by ATP and succinate at first site level of the respiratory chain in SMP.The RET rate was easily monitored by recording spectrophotometrically at 340 nm the production of NADH, arising from the reduction of exogenous NAD+ by RET.The toxicity values were expressed as the toxicant molar concentration which decreases the rate of reduction of NAD+ to an extent of 50 percent (EC50). The toxicity increased in the following order: Ni2+2+2+< Cd2+2+2++.The SMP data were compared with the toxicity values obtained from a variety of biological systems currently used for toxicity testing. The results obtained demonstrate that the SMP test generally provides a good estimate of metal toxicity for several fish and invertebrate species. This is demonstrated by the statistical parameters obtained in the regression analysis. The broadened 95% confidence intervals and, in particular, the poor correlations obtained for some aquatic organisms can be ascribed to the more complex metabolic interactions and competing toxic pathways in aquatic organisms, when compared to SMP.  相似文献   
138.
榄香烯对急性血瘀模型大鼠血液流变性的影响   总被引:1,自引:0,他引:1  
本文观察了榄香烯对急性血瘀模型大鼠血液流变性的影响。实验结果表明:榄香烯6.25-25mg/kg/d,ip×7d,可使血瘀模型鼠的高低切变率全血粘度和还原粘度、血浆粘度、血沉、红细胞聚集指数、纤维蛋白原及红细胞电泳时间等显著降低(P<0.05、P<0.01)。提示榄香烯有活血化瘀作用  相似文献   
139.
Copper-Putrescine-Pyridine (Cu-PuPy) is a membrane-permeable complex which efficiently dismutates superoxide. In excess of 0.1 mM it is highly cytotoxic and oxidizes cellular GSH with concomitant production of H2O2. Here we show that treatment of CHO cells with 0.2 mM Cu-PuPy (0-200 min) leads to an accumulation of H2O2. Organic hydroperoxides which are also formed at low levels in the presence of Cu-PuPy, increase significantly after removal of the copper complex. We conclude that Cu-PuPy acts as an oxidant until cellular GSH is depleted. However, by interfering with radical chain propagation reactions, it suppresses lipid peroxidation and thus substitutes for consumed physiological antioxidants in a later stage of treatment. This consistently explains our previous, seemingly paradox, finding that longer Cu-PuPy treatments may be significantly less toxic than shorter ones.  相似文献   
140.
Summary Iron tolerance of rice (Oryza sativa L.) was investigated using an oxygen depleted hydroculture system. Treatment with high concentrations of Fe2+ induced yellowing and bronzing symptoms as well as iron coatings at the root surface. Root and shoot growth were inhibited by increasing iron concentration in the medium. All symptoms were more pronounced in an iron sensitive cultivar (IR 64) compared to an iron tolerant one (IR 9764-45-2). Superoxide dismutase and peroxidase activity of root extracts of IR 97 were about twice that of IR 64 in untreated control plants. No significant increase of peroxidase activity was detected with increasing iron concentration in the medium. Catalase activity of IR 64 was slightly higher than that of IR 97, independent of iron concentration.Abbreviations SOD Superoxide dismutase (EC 1.15.1.1) - POD peroxidase (EC 1.11.1.7) - EDTA ethylenediamintetraacetic acid - fwt fresh weight - Hepes (N-[2-hydroxyethyl]piperazine-N-[2-ethanesulfonic acid]) - BSA bovine serum albumin - IR 97 IR 9764-45-2 an iron tolerant rice cultivar - IR 64 iron sensitive rice cultivar - PM plasma membrane  相似文献   
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