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61.
Iron is an indispensable element for vital activities in almost all living organisms. It is also a cofactor for many proteins, enzymes, and other essential complex biochemical processes. Therefore, iron trafficking is firmly regulated by Hepcidin (Hamp), which is regarded as the marker for iron accumulation. The disruption of iron homeostasis leads to oxidative stress that causes various human diseases, but this mechanism is still unclear. The aim of this study is to provide a better in vivo and in vitro understanding of how long‐term iron overload affects the gene expression and activities of some antioxidant enzymes, such as glucose 6‐phosphate dehydrogenase (G6PD), 6‐phosphogluconate dehydrogenase (6PGD), and glutathione reductase (GR) in the spleen. The findings of this study show that iron overload reduces the gene expression of G6pd, 6pgd, and Gr, but its actual effect was on the protein level.  相似文献   
62.
Synthesis of dechlorinase in Streptomyces sp. M7 was induced when the microorganism was grown in the presence of lindane (γ-hexachlorocyclohexane) as the only carbon source. Activity of cells grown with lindane was about four and half times higher compared to cells grown with glucose. Maximum dechlorinase activity was observed at 30°C in alkaline conditions pH (7.9) and the enzyme did not show cation dependency. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed one differential band with a molecular weight similar to serum albumin (M r 66,200), which corresponded to polynucleotide phosphorylase, an enzyme that plays an important role in the regulation system and could be involved in the regulation of the dechlorinase gene. Detected in cell-free extracts were γ-pentachlorocyclohexene and 1,3,4,6-tetrachloro-1,4-cyclohexadiene, both being products of the dechlorinase activity. This is the first time that the presence of an enzyme with dechlorinase activity has been demonstrated in an actinomycete strain isolated in Tucumán, Argentina. Characteristics of this enzyme revealed that Streptomyces sp. M7 could be useful in the future in bioremediation of soil or as a biosensor.  相似文献   
63.
Mixed cultures of Bacillus amyloliquefaciens MIR-41 and Zymomonas mobilis Flo-B3 showed a 2.5 fold increase in -amylase production, and a 20 times fold decrease in ethanol production compared with pure cultures. Enhanced -amylase production by B. amyloliquefaciens in mixed cultures after 24 h could be attributed to the lack of repression in the synthesis of -amylase by ethanol and protease inhibition by the pH of the culture medium.  相似文献   
64.
Interleukin-1 plays a role in normal homeostasis and in the inflammatory response which is deemed to be responsible for the development of major chronic diseases that are highly prevalent in the elderly. Aim of this study is to evaluate the factors influencing the serum levels of Interleukin-1 beta, in a large and representative population. Data were from the InCHIANTI project, a study of factors contributing to the decline of mobility in late life, which sampled people living in two sites in the surroundings of Florence. Blood samples were obtained from 1,292 participants and frozen aliquots were stored at -80 degrees C. The serum levels of several cytokines were measured by enzyme linked immunosorbent assay using an ultrasensitive commercial kit. Interleukin-1 beta serum levels were associated with congestive heart failure (p > 0.001) and angina (p = 0.02), with Ca2+ serum levels (p = 0.02), and with a history of dyslipidemia (p = 0.05). We found no association between serum IL-1beta level and age, sex, consumption of cardioactive drugs and serum levels of IL-1Ra, IL-6, sIL-6R, IL-10 and TNF-alpha. Our data could lend support to the hypothesis that IL-1beta is mainly involved in the functional alterations of cardiomyocytes under conditions marked by mononuclear cell infiltration and by downregulation of calcium.  相似文献   
65.
A comparison of the nematode-destroying capability of two nematophagous Arthrobotrys spp. (coded ART-1 and ART-2), isolated from soil samples, showed that ART-1 (LD50=290conidia/ml) was more efficient than ART-2 (LD50=725conidia/ml). The two isolates produce extracellular proteases in liquid culture. The proteases from both isolates had a temperature optimum of 50°C. The optimum pH for protease activity was in the range of 7.5–8 for ART-1 and 7.5–9 for ART-2. ART-1 produced more protease activity (13.3±0.72U/ml) than ART-2 (10.9±0.375U/ml). The proteases from ART-1 were more efficient in degrading nematodes than those of ART-2 by virtue of being produced in a larger quantity. We suggest that the difference in the nematode-destroying capability between the two strains is solely the result of the difference in the amount of extracellular proteases they produce.  相似文献   
66.
BackgroundAnthrax is a disease that affects humans and animals. In Ethiopia, anthrax is a reportable disease and assumed to be endemic, although laboratory confirmation has not been routinely performed until recently. We describe the findings from the investigation of two outbreaks in Amhara region.MethodsFollowing reports of suspected outbreaks in Wag Hamra zone (Outbreak 1) and South Gondar zone (Outbreak 2), multi-sectoral teams involving both animal and public health officials were deployed to investigate and establish control programs. A suspect case was defined as: sudden death with rapid bloating or bleeding from orifice(s) with unclotted blood (animals); and signs compatible with cutaneous, ingestion, or inhalation anthrax ≤7 days after exposure to a suspect animal (humans). Suspect human cases were interviewed using a standard questionnaire. Samples were collected from humans with suspected anthrax (Outbreak 1 and Outbreak 2) as well as dried meat of suspect animal cases (Outbreak 2). A case was confirmed if a positive test was returned using real-time polymerase chain reaction (qPCR).ResultsIn Outbreak 1, a total of 49 cows died due to suspected anthrax and 22 humans developed symptoms consistent with cutaneous anthrax (40% attack rate), two of whom died due to suspected ingestion anthrax. Three people were confirmed to have anthrax by qPCR. In Outbreak 2, anthrax was suspected to have caused the deaths of two livestock animals and one human. Subsequent investigation revealed 18 suspected cases of cutaneous anthrax in humans (27% attack rate). None of the 12 human samples collected tested positive, however, a swab taken from the dried meat of one animal case (goat) was positive by qPCR.ConclusionWe report the first qPCR-confirmed outbreaks of anthrax in Ethiopia. Both outbreaks were controlled through active case finding, carcass management, ring vaccination of livestock, training of health professionals and outreach with livestock owners. Human and animal health authorities should work together using a One Health approach to improve case reporting and vaccine coverage.  相似文献   
67.
Citrobacter spp., Enterobacter hormaechei subsp., Klebsiella variicola and Proteae tribe members are rarely isolated Enterobacterales increasingly implicated in nosocomial infections. Herein, we show that these species contain multiple genes encoding resistance to important antibiotics and are widely and globally distributed, being isolated from human, animal, plant, and environmental sources in 67 countries. Certain clones and clades of these species were internationally disseminated, serving as reservoirs and mediums for the global dissemination of antibiotic resistance genes. As they can easily transmit these genes to more pathogenic species, additional molecular surveillance studies should be undertaken to identify and contain these antibiotic-resistant species.  相似文献   
68.
In this study the effect of diabetes mellitus on atrial natriuretic peptide (ANP) receptors in streptozotocin- (STZ-) induced diabetic rat kidneys was studied. Moreover, plasma ANP concentration was evaluated in diabetic and control rats by using radioimmunoassay. In addition, the expression of ANP in the kidneys of control and diabetic rats was evaluated by immunohistochemistry. Body-weight loss and increased glucose levels were used as indices of diabetes mellitus in the STZ-induced rats. There was a significant loss in the body weight of the diabetic rats compared to controls. The efficacy of STZ administration was confirmed by rising blood glucose levels, which were significantly higher in diabetic rats compared to controls. Plasma ANP concentration was significantly greater in the diabetic rats in comparison with controls. Moreover, our immunohistochemical results show that the expression of ANP in diabetic rats was higher than that in age-matched controls. ANP was observed in the cells lining the proximal convoluted tubules in the cortex. The distribution and levels of ANP receptors in the kidneys of diabetic rats and age-matched controls were investigated using quantitative receptor autoradiography. Our results demonstrate significant decrease in ANP receptors in the kidneys of the diabetic rats compared to controls. The significant decrease was found in the juxtaglomerular medulla, inner medulla, and the papillae. The decrease in ANP receptors observed in the diabetic kidneys could have pathological consequences resulting in renal resistance to ANP in diabetes.  相似文献   
69.
Glutamate excitotoxicity plays a key role in inducing neuronal cell death in many neurological diseases. In mice, intranasal administration of kainic acid (KA), an analogue of the excitotoxin glutamate, results in hippocampal cell death and provides a well-characterized model for studies of human neurodegenerative diseases. In this study, we describe neurodegeneration and gliosis following intranasal administration of KA in C57BL/6 mice. By using Nissl's staining, neurodegeneration was found in area CA3 of hippocampus, and neuronal apoptosis was demonstrated by enhanced FAS(CD95/APO-1) expression detected by immunohistochemistry and Western blotting. Astrogliosis was exhibited by increased glial fibrillary acidic protein (GFAP) expression in the hippocampus and cortex. We also studied the profile of molecular expression on microglia in C57BL/6 mice. One and 3 days after KA administration, CD45, F4/80, CD86, MHCII, iNOS but not CD40 expression was enhanced or induced on microglia. In summary, KA administration results in an early microglial activation and a prolonged astrogliosis in C57BL/6 mice.  相似文献   
70.
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