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51.
Current knowledge of resistance (R) genes and their use for genetic improvement in buffalograss (Buchloe dactyloides [Nutt.] Engelm.) lag behind most crop plants. This study was conducted to clone and characterize cDNA encoding R gene-like (RGL) sequences in buffalograss. This report is the first to clone and characterize of buffalograss RGLs. Degenerate primers designed from the conserved motifs of known R genes were used to amplify RGLs and fragments of expected size were isolated and cloned. Sequence analysis of cDNA clones and analysis of putative translation products revealed that most encoded amino acid sequences shared the similar conserved motifs found in the cloned plant disease resistance genes PRS2, MLA6, L6, RPMI, and Xa1. These results indicated diversity of the R gene candidate sequences in buffalograss. Analysis of 5′ rapid amplification of cDNA ends (RACE), applied to investigate upstream of RGLs, indicated that regulatory sequences such as TATA box were conserved among the RGLs identified. The cloned RGL in this study will further enhance our knowledge on organization, function, and evolution of R gene family in buffalo grass. With the sequences of the primers and sizes of the markers provided, these RGL markers are readily available for use in a genomics-assisted selection in buffalograss.  相似文献   
52.
ABSTRACT: BACKGROUND: Aggregation of alpha-synuclein (alphasyn) and resulting cytotoxicity is a hallmark of sporadic and familial Parkinson's disease (PD) as well as dementia with Lewy bodies, with recent evidence implicating oligomeric and pre-fibrillar forms of alphasyn as the pathogenic species. Recent in vitro studies support the idea of transcellular spread of extracellular, secreted alphasyn across membranes. The aim of this study is to characterize the transcellular spread of alphasyn oligomers and determine their extracellular location. RESULTS: Using a novel protein fragment complementation assay where alphasyn is fused to non-bioluminescent amino-or carboxy-terminus fragments of humanized Gaussia Luciferase we demonstrate here that alphasyn oligomers can be found in at least two extracellular fractions: either associated with exosomes or free. Exosome-associated alphasyn oligomers are more likely to be taken up by recipient cells and can induce more toxicity compared to free alphasyn oligomers. Specifically, we determine that alphasyn oligomers are present on both the outside as well as inside of exosomes. Notably, the pathway of secretion of alphasyn oligomers is strongly influenced by autophagic activity. CONCLUSIONS: Our data suggest that alphasyn may be secreted via different secretory pathways. We hypothesize that exosome-mediated release of alphasyn oligomers is a mechanism whereby cells clear toxic alphasyn oligomers when autophagic mechanisms fail to be sufficient. Preventing the early events in alphasyn exosomal release and uptake by inducing autophagy may be a novel approach to halt disease spreading in PD and other synucleinopathies.  相似文献   
53.
In this study, to identify mercury (Hg) toxicity and whether selenium (Se) has any role in alleviation of this toxicity, it was investigated the changes in hematological and serum biochemical parameters of Oreochromis niloticus. Fish were exposed to 0.01 and 0.1 mg/L Hg and 0.01 mg/L Hg + 0.1 mg/L Se and 0.1 mg/L Hg + 1.0 mg/L Se for 7 and 14 days. The exposure of O. niloticus to Hg alone resulted in decreases in red blood cell, white blood cell, hemoglobin, hematocrit values, and cholinesterase activity while it increased in alanine aminotransferase and aspartate aminotransferase activities and cortisol and glucose levels. Se, in combination with Hg, partially or totally caused an alleviation for the toxic effect of Hg on the above mentioned hematological and biochemical parameters. The results of our study showed that Se has a protective effect against toxicity induced by Hg.  相似文献   
54.

Background

In the management of malignant pleural mesothelioma, radiotherapy has been used for the purpose of prophylaxis to reduce the incidence of recurrence at surgical insertion sites or palliate the symptoms.

Aim

The purpose of the study was to evaluate the techniques and effectiveness of radiotherapy in malignant pleural mesothelioma.

Materials and methods

Forty-four (18 female, 26 male) patients diagnosed with malignant pleural mesothelioma were retrospectively evaluated. All patients had surgery or thoracoscopic biopsy for diagnosis, staging or treatment and all received palliative or prophylactic radiotherapy. Fifty-seven percent of the patients received chemotherapy.

Results

Prophylactic radiation was applied to 27 patients with 4–15 MeV electron energies. The median radiotherapy dose was 30 Gy with 3 Gy daily fraction dose. During treatment, 12 patients had grade 1 erythema according to the RTOG scale. In 3 (12%) patients, a local failure at treatment field was observed. Palliative radiotherapy was applied to 17 patients for pain palliation. The median radiation dose was 40 Gy with 2 Gy daily fraction dose by using 6–18 MV photon and/or 4–12 MeV electron energies. Two patients had grade 1 erythema and one patient had grade 2 odynophagy according to the RTOG scale. For 10 (59%) patients, palliation of chest pain was delivered. No late toxicity was observed for all cases.

Conclusion

Our experience showed that prophylactic and palliative radiotherapy are effective and safe therapy modalities in malignant pleural mesothelioma in preventing seeding metastasis at intervention sites or relieving pain. Prospective randomized studies are still needed to determine the benefits of radiotherapy application and to indicate optimum dose schemes.  相似文献   
55.
In this study, wheat straw was pretreated with a microfluidizer to improve its enzymatic hydrolysis and ethanol yields. The pretreatment was performed at various pressures (500, 1000, and 1500 bar) and solid loadings (1, 2, and 3%). The microfluidized biomass was then subjected to hydrolysis and simultaneous saccharification and co-fermentation (SSCF) experiments at different enzyme loadings (5, 10, and 15 FPU/g dry wheat straw) using a mutant yeast. The results indicated that the microfluidization method alters the structure of biomass and leads to a reduction in lignin content. The samples pretreated at 1% solid loading contained the minimum lignin concentration and provided the maximum sugar and ethanol yields. These results signified that the microfluidization method is more effective on biomass at low solid loadings. The process conditions were optimized for higher ethanol and sugar yields using response surface methodology (RSM). The optimum pressure and solid and enzyme loadings were found as 1500 bar, 1%, and 15 FPU/g dry wheat straw, respectively. The yields obtained at this condition were 82%, 94%, and 65% for glucose, xylose, and ethanol, respectively. High sugar yields implied that microfluidization is an effective pretreatment method for cellulosic ethanol production. On the other hand, low ethanol yield may indicate that the microorganism was sensitive to inhibitory compounds present in the fermentation medium.  相似文献   
56.
Existing inference methods for estimating the strength of balancing selection in multi-locus genotypes rely on the assumption that there are no epistatic interactions between loci. Complex systems in which balancing selection is prevalent, such as sets of human immune system genes, are known to contain components that interact epistatically. Therefore, current methods may not produce reliable inference on the strength of selection at these loci. In this paper, we address this problem by presenting statistical methods that can account for epistatic interactions in making inference about balancing selection. A theoretical result due to Fearnhead (2006) is used to build a multi-locus Wright-Fisher model of balancing selection, allowing for epistatic interactions among loci. Antagonistic and synergistic types of interactions are examined. The joint posterior distribution of the selection and mutation parameters is sampled by Markov chain Monte Carlo methods, and the plausibility of models is assessed via Bayes factors. As a component of the inference process, an algorithm to generate multi-locus allele frequencies under balancing selection models with epistasis is also presented. Recent evidence on interactions among a set of human immune system genes is introduced as a motivating biological system for the epistatic model, and data on these genes are used to demonstrate the methods.  相似文献   
57.
Stem cell markers are utilized to isolate or identify stem cells. So far, many stem-cell-specific markers have been described, although some of them turned out to be not as specific as it was originally proposed. In this study, we sought to search for a specific stem cell marker that would be phenotypically helpful, characteristically specific, economically affordable and easy to use. Because organelles are one of the major characteristics of eukaryotic cells, we asked the question of whether organelle characteristics might be a useful tool for stem cell characterization. We studied distribution and characteristics of the endoplasmic reticulum, the mitochondria and the Golgi apparatus in human dental-pulp-derived mesenchymal stem cells before and during osteogenic differentiation. Although it was not possible to find a useful macromolecular marker for stem cell characterization, we found that during osteogenic differentiation, the stem cells changed their Golgi characteristics and displayed a unique in vivo pattern. We analysed these unique Golgi structures and proposed a potential osteogenic differentiation marker for human dental-pulp-derived mesenchymal stem cells. This pattern may be used in the evaluation of osteogenic differentiation.  相似文献   
58.
59.
Molecular Biology Reports - Magnesium sulfide nanoparticles (MgS NPs) is a nanomaterial that has an important place in diagnosis, treatment, diagnosis, and drug delivery systems. Neuroblastoma, a...  相似文献   
60.
Neuroblastoma is one of the most widely seen under the age of 15 tumors that occur in the adrenal medulla and sympathetic ganglia. Cisplatin, an antineoplastic drug, is a Platinum-based compound and is known to inhibit the proliferation of neuroblastoma cells. Effective applications of nanoparticles in biomedical areas such as biomolecular, antimicrobial detection and diagnosis, tissue engineering, theranostics, biomarking, drug delivery, and anti-cancer have been investigated in many studies. This study aims to prepare the bioconjugates of CoS (cobalt sulfide) nanoparticles (NPs) with cisplatin combination groups and to evaluate their effects on the neuroblastoma cell line. Nanoparticle synthesis was done using the green synthesis technique using Punica granatum plant extract. The size and shape of CoS NPs were characterized by SEM, FT-IR, and XRD. Zeta potential was confirmed by the DLS study. For this purpose, the SH-SY5Y neuroblastoma cell line was cultured in a suitable cell culture medium. Cisplatin 5 µg and different concentrations (Cisplatin + CoS NPs bioconjugates (5, 10, 25, 50, 75 μg) doses were applied to SH-SY5Y neuroblastoma cell lines for 24 h. TAC, TOS and MTT tests were performed 24 h after the application. According to the MTT test results, cisplatin and CoS NP combinations reduced the proliferation of neuroblastoma cells by 78 to 57% compared to the cisplatin control. From the findings obtained; the most effective Bio-conjugate group was Cisplatin 5 μg/mL + CoS 75 μg/mL.  相似文献   
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