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991.
Hongxia Che Xueyuan Fu Lingyu Zhang Xiang Gao Min Wen Lei Du Changhu Xue Jie Xu Yuming Wang 《Cellular and molecular neurobiology》2018,38(3):657-668
Neurodegenerative diseases are defined by progressive loss of specific neuronal cell populations and are associated with protein aggregates. Oxidative stress has been implicated in their pathological processes. Previous studies revealed that docosahexaenoic acid (DHA) is beneficial in neurodegenerative diseases. Phospholipids (PLs) derived from marine products are rich in DHA and eicosapentaenoic acid (EPA). In the present study, we investigated the neuroprotective effects of DHA-enriched and unenriched phosphatidylcholine (PC) and phosphatidylserine (PS) on oxidative stress induced by hydrogen peroxide (H2O2) and tert-butylhydroperoxide in PC12 cells. Cell viability and leakage of lactate dehydrogenase results showed that the neuroprotective effect of PS was superior to that of PC. DHA- and EPA-enriched PC and PS were superior to that without DHA or EPA; in addition, the improvement with n-3 polyunsaturated fatty acid-enriched PS (n-3 PS) was dose dependent. Acridine orange/ethidium bromide staining showed that DHA- and EPA-enriched PS (DHA/EPA-PS) could significantly inhibit apoptosis. Mechanistic studies revealed that EPA-PS and DHA-PS were effective to increase superoxide dismutase (SOD) levels by 48.4 and 58.2 % and total antioxidant capacity (T-AOC) level by 51 and 94 %, respectively, in the H2O2 model. Similar results for SOD and T-AOC levels were shown in the t-BHP model. EPA/DHA-PS could downregulate the messenger RNA level of Caspase-3, Caspase-9, and Bax, upregulate Bcl-2, inhibit Bax, and increase Bcl-2 at protein level. In conclusion, EPA/DHA-PS could protect PC12 cells from oxidative stress and prevent mitochondrial-mediated apoptosis. Our findings indicate that the neuroprotective effects of DHA/EPA-PLs depend on the molecular form. Further studies are necessary to reveal detailed mechanisms and structure–effect relationships. 相似文献
992.
Piotr Golinski Stanisław Wnuk Jerzy Chełkowski Małgorzata Schollenberger 《Mycotoxin Research》1987,3(1):49-52
Eighteen isolates ofFusarium avenaceum Fries Sacc. originating from cereals, potato and carrot from Poland synthesized Avenacein Y in amounts ranging from 0.01 to 2.0 g/kg of wheat grain. The compound was produced in 1 kg of corn kernels by isolate KF-58, isolated, identified and used to test for antibiotic activity against plant pathogenic fungi of 11 genera. Application of Avenacein Y caused slight decrease of mycelium growth in four species only. 相似文献
993.
S. Mori H. Hasegawa R. Che H. Nakanishi M. Murakami 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,77(1):44-48
Summary In four rice (Oryza sativa L.) mutants resistant to hydroxy-L-proline (Hyp), HYP101, HYP203, HYP205 and HYP210, and in their original variety, Nipponbare, free proline and Hyp contents in the seeds and in the 14-day-old seedlings have been determined. The four mutants can be divided into two groups: HYP101 and HYP203 are classified as to recessive gene and the levels of free proline are similar to that of the original variety; the second group includes mutants HYP205 and HYP210 where the Hyp resistance is transmitted heterozygously and, both in the seeds and in the seedlings, a remarkable increase in free proline content is observed. In particular, free proline contents in the seeds of HYP205 and HYP210 are, respectively, 24 and 12 times that of the original variety. Hyp is detected only in the seedlings cultured with Hyp solution. In the Hyp resistant seedlings of HYP205 and HYP210, Hyp contents are twice that of the original variety and less than half in the seedlings of HYP101 and HYP203. Hyp resistance and differential proline levels are also evident in the callus initiated from the mutants. This suggests that the Hyp resistant mutants are good genetic markers both in planta and in vitro. The Hyp mutants are also discussed with regard to stress resistance. 相似文献
994.
Zili Kong Wenshan Lv Yunyang Wang Yajing Huang Kui Che Huiqi Nan Yu Xin Jiaxuan Wang Jintao Chen Yangang Wang Jingwei Chi 《Journal of biochemical and molecular toxicology》2023,37(10):e23445
Diabetic nephropathy (DN) affects around 40% of people with diabetes, the final outcome of which is end-stage renal disease. The deficiency of autophagy and excessive oxidative stress have been found to participate in the pathogenesis of DN. Sinensetin (SIN) has been proven to have strong antioxidant capability. However, the effect of SIN on DN has not been studied. We examined the effect of SIN on cell viability and autophagy in the podocyte cell line, MPC5 cells, treated with high glucose (HG). For in vivo studies, DN mice models were established by intraperitoneal injected with streptozotocin (40 mg/kg) for 5 consecutive days and fed with a 60% high-fat diet, and SIN was given (10, 20, and 40 mg/kg) for 8 weeks via intraperitoneal injection. The results showed that SIN could protect MPC5 cells against HG-induced damage and significantly improve the renal function of DN mice. Moreover, SIN remarkably restored the autophagy activity of MPC5 cells which was inhibited under HG conditions. Consistent with this, SIN efficiently improved autophagy in the kidney tissue of DN mice. In brief, our findings demonstrated the protective effect of SIN on DN via restoring the autophagic function, which might provide a basis for drug development. 相似文献
995.
The paper presents 21Fusarium species occurring in Poland on the field crops /mostly on cereals, maize, potato and Papilionaceae plants/, woody plants, grasses, vegetables and ornamentals as well as on kernels or seeds of these hosts and soils. Additionally the commonly observed symptoms on above-mentioned plants and the informations about regions of the highest disease occurrence are added.However the paper results mainly from authors’ investigation on theFusarium species occurrence in Poland, it encloses also the available, post-war literature data on the fusariosis in Poland in the past.Majority ofFusarium species cited had been identified according to Nelson et al, taxonomic system. Comparative listing of the monographs / 1,11, 21/ is presented. 相似文献
996.
Fusarium graminearum KF-376 isolate was found to be able to form simultaneously three toxic metabolites: zearalenone (FF-2), deoxynivalenol (DON) and 15-acetyldeoxynivalenol (15-AcDON). Toxins were extracted with methanol — water 3:1 (v/v) and purified by liquid chromatography on charcoal — Kieselgel 60 column (preliminary) and Aluminiumoxid 90 column. Final separation of the metabolites was achived on Kieselgel 60 — Aluminiumoxid 90 column. 相似文献
997.
E Buschman R J Arceci J M Croop M Che I M Arias D E Housman P Gros 《The Journal of biological chemistry》1992,267(25):18093-18099
We have produced antibodies specific for the three P-glycoprotein (P-gp) isoforms encoded by the mouse mdr1, mdr2, and mdr3 genes. The anti-Mdr2 and anti-Mdr3 antibodies were generated against synthetic peptides derived from the "linker" region, whereas the anti-Mdr1 antibody was raised against a fusion protein containing the amino terminus of Mdr1. Western blot analysis showed that the three antibodies could discriminate between the three isoforms in membrane fractions from Hamster cells transfected with the corresponding full-length or chimeric mdr cDNAs. Immunocytochemistry studies of mdr-transfected cells showed that the three antibodies specifically recognized each P-gp isoform expressed in whole cells. Immunoblotting of normal mouse tissues revealed that the Mdr2 isoform was expressed at very high levels in liver canalicular membrane vesicles (CMV) but not in membrane vesicles prepared from the basolateral (sinusoidal) domain (SMV). Mdr3 was detected in intestinal brush border membrane vesicles and also in CMV, although at levels much lower than Mdr2. Mdr1 was not detected in CMV or SMV but was detected in endometrial tissue from the gravid uterus. Photolabeling experiments with [125I]iodoarylazidoprazosin followed by immunoprecipitation with isoform-specific antibodies indicated that, in CMV, Mdr3 but not Mdr2 could bind the drug analogue. 相似文献
998.
J Sroczyński E Che?mecka J Piotrowski M Snit 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(14-16):262-265
The study was aimed at analysing the epidemiological structure of patients with liver cirrhosis without HBsAg treated in 1980-1988. There were 231 of such cases in this period of time. The most frequent cause of liver cirrhosis in patients under 60 years of life was chronic alcoholism whereas 40% of the diagnosed liver cirrhosis in older persons was of unclear etiology. Patients complaints, clinical examinations, and results of the laboratory tests were analysed. The course of the disease was more severe in alcohol-produced liver cirrhosis leading to the haemorrhage from esophageal varices in 36%, and coma in 8% of cases. Alcohol-produced liver cirrhosis promoted other complications such as: cancer of the liver, hepato-renal syndrome or encephalopathy. Liver cirrhosis of unclear etiology in the elderly may be a consequence of the prolonged exposition to environmental pollutants. More severe course of alcohol-produced liver cirrhosis may depend on simultaneous action of two harmful factors: alcohol and environmental pollutants. 相似文献
999.
The distal aspect of the housefly ommatidium was surveyed by the scanning electron microscope. Attention was directed to the somal eminence of the superior central cell and the lens to large pigment cell junction. The underside of each lens facet exhibits six hexagonally arranged incisures. Into each of these indentations are fitted several large pigment cells. This hexagonal indentation appears to be a tenacious anchorage. Two corneal pigment cells laterally encircle the pseudocone and at their proximal extension they enclose the Semper cells and neck of the retinula. The somal eminence of the superior central cell is about 10 mum from the base of the corneal pigment cell enclosure. Micrographs were used to construct a diagram of the ommatidium above the basement membrane. Suggestions are made as to the functional correlates of the observed ommatidial structures. 相似文献
1000.
Considerable progress has been made in understanding the influence of physical and genetic factors on the patterns of cell division in various model systems. However, how each of these factors directs changes in subcellular structures has remained unclear. Generic machineries for the execution of cell expansion and division have been characterized, but how these are influenced by genetic regulators and physical cell properties remains an open question. To a large degree, the complexity of growing post‐embryonic tissues and a lack of precise predictability have prevented the extraction of rigid correlations between subcellular structures and future orientation of cell division. The Arabidopsis embryo offers an exquisitely predictable and simple model for studying such correlations, but so far the tools and methodology for studying subcellular structures in the early embryo have been lacking. Here, we describe a set of markers to visualize a range of subcellular structures in the early Arabidopsis embryo. We have designed a series of fluorescent cellular reporters optimized for embryos, and demonstrate the effectiveness of using these ‘ACE’ reporters with simple three‐dimensional imaging procedures that preserve delicate cellular structures. We describe the ontogeny of subcellular structures in the early embryo and find that central/peripheral cell polarity is established much earlier than suspected. In addition, we show that the actin and microtubule cytoskeleton has distinct topologies in the embryo. These tools and methods will allow detailed analysis of the events of cellular reorganization that underlie morphogenesis in the Arabidopsis embryo. 相似文献