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131.
132.
Gheisari Y Ahmadbeigi N Naderi M Nassiri SM Nadri S Soleimani M 《Cell biology international》2011,35(3):209-213
Paracrine secretion of mediators may be the main route by which stem cells protect against injuries. Stem cells commonly secrete different bioactive molecules. In this study, we examined the hypothesis that administration of conditioned media of stem cells can diminish the burden of kidney injury. A mouse model of cisplatin-induced nephropathy was developed to test the putative renoprotective effects of conditioned media of human umbilical cord blood USSCs (unrestricted somatic stem cells) as well as mouse bone marrow MSCs (mesenchymal stem cells). None of these two types of conditioned medium could protect against kidney failure in terms of serum urea and creatinine, histopathologic examinations and physical activity score. Neither MSC- nor USSC-conditioned media were effective in protecting against kidney injury in our study. Possible explanations for our observations are offered, and related literature is reviewed. 相似文献
133.
Sedigheh Esmaeilzadeh Bahabadi Mozafar Sharifi Naser Safaie Jun Murata Tohru Yamagaki Honoo Satake 《Plant biotechnology reports》2011,5(4):367-373
Linum album accumulates anti-tumor podophyllotoxin (PTOX) and its related lignans, which were originally isolated from an endangered
species Podophyllum. In the present study, we examined the effects of five fungal extracts on the production of lignans in L. album cell cultures. Fusarium graminearum extract induced the highest increase of PTOX [143 μg g−1 dry weight (DW) of the L. album cell culture], while Rhizopus stolonifer extract enhanced the accumulation of lariciresinol up to 364 μg g−1 DW, instead of PTOX. Typical elicitors, such as chitin, chitosan, or methyl jasmonate (MeJA), were shown to be less effective
in lignan production in L. album cell cultures. These results verified the advantages of fungal extracts to increase lignan production in L. album cell culture, and suggested potential on-demand metabolic engineering of lignan biosynthesis using differential fungal extracts. 相似文献
134.
The C terminus of the anaphylatoxin C3a generated upon complement activation represents a neoantigenic determinant with diagnostic potential 总被引:4,自引:0,他引:4
R Burger G Zilow A Bader A Friedlein W Naser 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(2):553-558
Activation of the C component C3 results in generation of the anaphylatoxin C3a. The C3a polypeptide chain consists of 77 amino acids. The active site of this potent mediator, which also has immunoregulatory function resides in its C terminus. This report demonstrates that the C terminus of C3a (C3a-desArg) exposed by proteolytic cleavage from C3 represents a neoantigenic determinant. Two mAb specific for this epitope were obtained after immunization with the synthetic octapeptide (OP) Arg-Ala-Ser-His-Leu-Gly-Leu-Ala [C3a(69-76)] coupled to the carrier keyhole limpet hemocyanin (KLH). These anti-C3a(69-76) antibodies (H453 and H454) reacted in an ELISA system with C3a and KLH-OP but not with C3 or with KLH alone. Free OP efficiently blocked binding of the antibodies to C3a, whereas binding of another anti-C3a mAb (H13) remained unaffected. In immunoblotting analysis, the anti-C3a(69-76) mAb reacted with purified C3a but failed to react with the denatured, noncleaved C3. A novel quantitative C3a-ELISA was established with the anti-C3a(69-76) mAb. It had a sensitivity in the nanogram range (1 to 5 ng/ml). The C3a determination was not impaired by the presence of high concentrations of C3. Therefore, C3 removal was not required in contrast to the previously described C3a assays. This C3a ELISA might facilitate clinical C3a quantitation, e.g., in samples from patients with adult respiratory distress syndrome. In these patients, C3a determination in the early phase of the disease is of diagnostic relevance and has prognostic value. 相似文献
135.
Ali Shahi-Gharahlar Zabihollah Zamani Reza Fatahi Naser Bouzari 《Biochemical Systematics and Ecology》2011,39(4-6):826-833
As Iran is one of the main origins of Prunus germplasm. In this study, ISSR markers were used for genetic diversity evaluation of 39 accessions of subgenus Cerasus belonging to six species i.e. Prunus avium L., Prunus cerasus L., Prunus mahaleb L., Prunus incana Pall., Prunus microcarpa Boiss., and Prunus brachypetala Boiss.. With 12 ISSR primers, 151 polymorphic bands were detected with polymorphism ratio range of 81.8%–100%. The lowest similarity (0.04) was found between P. avium and P. microcarpa genotypes and the mean of similarity between all genotypes was 0.28. Cluster analysis separated improved cultivars from wild accessions. Improved cherry cultivars and rootstocks were placed closer to the P. avium than the other species. The principal coordinate analysis (PCoA) supported the cluster analysis results. The wild accessions were separated according to their species and collection sites. ISSR markers are useful techniques for genetic diversity evaluation in Prunus subgenus Cerasus. 相似文献
136.
137.
The paper presents integrated measurements of N fixation, net mineralisation, pasture yield and change in soil mineral N over a 12 month period for dairy pastures on a sandy loam soil in the South East of South Australia. The two adjacent pastures studied were an irrigated perennial white clover-ryegrass and an annual non-irrigated subterranean clover with mixed annual grasses. This produced the most comprehensive mineral N balance reported for grazed pastures, to the authors' knowledge, allowing calculation of gaseous and leaching losses of N (210 kg ha–1 in the irrigated and paddock and 81 kg ha–1 in the non irrigated paddock) primarily from urine patches. In both paddocks these losses were about three times the N yield in milk (61 and 28 kg N ha–1 respectively) and were replenished by biological N fixation (294 and 100 kg N ha–1). However, mineralisation of soil organic N, excretal N and pasture residues (687 and 438 kg N ha–1) was the major source of mineral N for cycling and losses. The results demonstrate the enormous impact of pasture management on N fluxes and reinforce the importance of livestock urine on the magnitude of N fluxes including gaseous and leaching losses. 相似文献
138.
Fatemeh Aliabadi Marjan Ajami Hamidreza Pazoki–Toroudi 《BioEssays : news and reviews in molecular, cellular and developmental biology》2020,42(12):2000198
The outbreak of a new, potentially fatal virus, SARS-COV-2, which started in December 2019 in Wuhan, China, and since developed into a pandemic has stimulated research for an effective treatment and vaccine. For this research to be successful, it is necessary to understand the pathology of the virus. So far, we know that this virus can harm different organs of the body. Although the exact mechanisms are still unknown, this phenomenon may result from the body's secretion of prostaglandin E2 (PGE2), which is involved in several inflammation and immunity pathways. Noticeably, the expression of this molecule can lead to a cytokine storm causing a variety of side effects. In this paper, we discuss those side effects in SARS-COV-2 infection separately to determine whether PGE2 is, indeed, an important causative factor. Lastly, we propose a mechanism by which PGE2 production increases in response to COVID-19 disease and suggest the possible direct relation between PGE2 levels and the severity of this disease. Also see the video abstract here: https://youtu.be/SnPFAcjxxKw. 相似文献
139.
Soheila Mirzaei Ebrahim Mohammadi Goltapeh Masoud Shams-Bakhsh Naser Safaie Mehrdad Chaichi 《Journal of Phytopathology》2009,157(7-8):474-482
Forty-four Botrytis cinerea isolates from different hosts and geographical regions were studied for colony morphology, mycelial growth rate at different temperatures, pathogenicity and molecular diversity. Botrytis cinerea isolates had temperature optima of 20–25°C and isolates showed variation in growth rate at different temperatures. Two morphological types were identified among tested isolates: mycelial and sclerotial. The pathogenicity of isolates was tested on grapevine leaves, and it was revealed that nine of 44 isolates were non-pathogenic and among them seven were of mycelial type. There was no correlation between mycelium growth rate and pathogenicity. Genetic diversity was investigated using nine arbitrary decaprimers. No relationship was found between molecular clusters and geographical region or sampling time; whereas isolates from the same plant host tended to cluster with each other. Seven of nine non-pathogenic isolates were separated from pathogenic ones. 相似文献
140.
Tarek K. Motawi Hebatallah A. Darwish Manal A. Hamed Nagy S. El-Rigal Asmaa F. Aboul Naser 《Molecular neurobiology》2017,54(3):1601-1611
Diabetes mellitus (DM) is characterized by hyperglycemia due to insulin inactivity or insufficiency with increasing risk of developing specific complications, including retinopathy, nephropathy, neuropathy, and atherosclerosis. The aim of the present study is to evaluate the efficacy of coenzyme Q10 (CoQ10), niacin, as well as their combination in ameliorating brain disorders associated with streptozotocin (STZ)-induced diabetes in rats. Glibenclamide, a reference diabetic drug, and donepezil, an acetylcholine inhibitor drug, were also evaluated. Diabetes was induced by single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). One-month diabetic rats were treated with the selected drugs daily for another two consecutive weeks. The evaluation was done through the estimation of the levels of blood glucose, serum insulin, and oxidative stress markers: malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH); neurotransmitters: acetylcholine (Ach) and dopamine (DA); vasoconstrictor indices: intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1(VCAM-1), and angiotensin II (Ang II); and apoptosis markers: tumor necrosis factor-α (TNF-α) and caspase-3 as well as the histopathological picture of the cerebellum region of the brain. The results revealed that the combination of niacin and CoQ10 improved most of the measured parameters with variable degrees. In conclusion, niacin and CoQ10 are promising dietary supplements in the management of diabetic encephalopathy. 相似文献