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991.
通过优化Percoll密度梯度离心技术,从大黄鱼 (Larmichthys crocea) 头肾组织中分离纯化巨噬细胞,并优化细胞培养条件。对所分离细胞进行形态学分析、普通光镜和电镜超微结构观察以及细胞功能验证实验。实验结果表明:细胞单层置于22℃无CO2恒温培养箱中,于L15培养基中培养5d后仍保持较高的活力。普通光镜和电镜观察到大黄鱼头肾巨噬细胞具有伪足发生和较强的吞噬能力、胞浆中富含线粒体以及吞噬小泡。巨噬细胞与不同浓度(0、0.1、1、20 μg/mL)的脂多糖(LPS,Escherichia coli 055:B5)分别孵育3h和24h。施加LPS刺激后,细胞呼吸暴发活性随LPS浓度以及孵育时间变化而变化。孵育3h后,0.1 μg/mL LPS协同PMA可显著诱导巨噬细胞活性氧中间体(ROI)的产生。孵育24h后,所有处理组LPS协同PMA显著抑制细胞ROI的生成(P 0.05)。未添加PMA时, 经1 μg/mL LPS孵育3h和24h后的巨噬细胞细胞ROI的生成量显著降低(P 0.05), 其他LPS处理组间细胞ROI的生成量无显著差异。    相似文献   
992.
To date, it is well-established that mitochondrial dysfunction does not only play a vital role in cancer but also in other pathological conditions such as neurodegenerative diseases and inflammation. An important tool for the analysis of cellular metabolism is the application of stable isotope labeled substrates, which allow for the tracing of atoms throughout metabolic networks. While such analyses yield very detailed information about intracellular fluxes, the determination of compartment specific fluxes is far more challenging. Most approaches for the deconvolution of compartmented metabolism use computational models whereas experimental methods are rare. Here, we developed an experimental setup based on selective permeabilization of the cytosolic membrane that allows for the administration of stable isotope labeled substrates directly to mitochondria. We demonstrate how this approach can be used to infer metabolic changes in mitochondria induced by either chemical or genetic perturbations and give an outlook on its potential applications.  相似文献   
993.
The growing prevalence of metabolic diseases including fatty liver disease and Type 2 diabetes has increased the emphasis on understanding metabolism at the mechanistic level and how it is perturbed in disease. Metabolomics is a continually expanding field that seeks to measure metabolites in biological systems during a physiological stimulus or a genetic alteration. Typically, metabolomics studies provide total pool sizes of metabolites rather than dynamic flux measurements. More recently there has been a resurgence in approaches that use stable isotopes (e.g. 2H and 13C) for the unambiguous tracking of individual atoms through compartmentalised metabolic networks in humans to determine underlying mechanisms. This is known as metabolic flux analysis and enables the capture of a dynamic picture of the metabolome and its interactions with the genome and proteome. In this review, we describe current approaches using stable isotope labelling in the field of metabolomics and provide examples of studies that led to an improved understanding of glucose, fatty acid and amino acid metabolism in humans, particularly in relation to metabolic disease. Examples include the use of stable isotopes of glucose to study tumour bioenergetics as well as brain metabolism during traumatic brain injury. Lipid tracers have also been used to measure non-esterified fatty acid production whilst amino acid tracers have been used to study the rate of protein digestion on whole body postprandial protein metabolism. In addition, we illustrate the use of stable isotopes for measuring flux in human physiology by providing examples of breath tests to measure insulin resistance and gastric emptying rates.  相似文献   
994.
Extractive fermentation with nonionic surfactants is a potential method for producing Monascus pigments. In this study, the correlation between mycelium morphology and pigment production was investigated in extractive fermentation of Monascus anka GIM 3.592. The results demonstrated that pigment biosynthesis was associated with mycelial morphology and the accumulation of granular inclusions in cells. The physiological status in terms of hyphal and pellet diameters exhibited an excellent correlation with pigment accumulation, especially the yield of extracellular pigment in extractive fermentation (r > 0.85, p < 0.05). Nonionic surfactants could reduce pigment yield by influencing the morphology of hyphae and mycelium pellets. High yields of both intracellular and extracellular pigments could be achieved by controlling variations in hyphal diameters in two-stage extractive fermentation. Moreover, continuous extractive fermentation led to stable pigment production, with a relatively high productivity of total pigments reaching 72.3 AU/day. This study proposed a simple method for monitoring pigment biosynthesis in extractive fermentation using mycelium morphology as an indicating factor.  相似文献   
995.
The increasing prevalence of infections involving intracellular apicomplexan parasites such as Plasmodium, Toxoplasma, and Cryptosporidium (the causative agents of malaria, toxoplasmosis, and cryptosporidiosis, respectively) represent a significant global healthcare burden. Despite their significance, few treatments are available; a situation that is likely to deteriorate with the emergence of new resistant strains of parasites. To lay the foundation for programs of drug discovery and vaccine development, genome sequences for many of these organisms have been generated, together with large-scale expression and proteomic datasets. Comparative analyses of these datasets are beginning to identify the molecular innovations supporting both conserved processes mediating fundamental roles in parasite survival and persistence, as well as lineage-specific adaptations associated with divergent life-cycle strategies. The challenge is how best to exploit these data to derive insights into parasite virulence and identify those genes representing the most amenable targets. In this review, we outline genomic datasets currently available for apicomplexans and discuss biological insights that have emerged as a consequence of their analysis. Of particular interest are systems-based resources, focusing on areas of metabolism and host invasion that are opening up opportunities for discovering new therapeutic targets.  相似文献   
996.
Evidence is mounting for a relationship between human semen quality and environmental/lifestyle/socioeconomic factors including long term health outcomes such as mortality. The relationship between pre-freeze and post-thaw semen quality in cancer patients and these factors are unknown. Frozen semen from 217 cancer patients was thawed and analysed using a validated CASA method. Post-thaw quality was matched and compared with WHO semen analysis performed prior to storage. The English Indices of Deprivation 2010 were matched with patients and then examined for relationships with pre-freeze and post-thaw semen quality. There is a relationship between semen quality and deprivation in cancer patients. Compared with pre-freeze semen quality, post-thaw semen quality has a stronger relationship with deprivation. Sperm cryopreservation may have potential as a systemic health diagnostic test and is predictive of cancer patient mortality.  相似文献   
997.
In order to evaluate the anti-influenza virus activity of the effective monomer from Folium Isatidis (FI) in vivo, we established mice model with viral pneumonia and divided them into 3 different dose groups, then observed their lung indexes, pulmonary pathological changes, pulmonary virus hemagglitination titers, living time and death rates. The results showed that the monomer could reduce the pulmonary index from 2.64 to 1.93, 1.63 and 1.40 (P<0.01) and decrease the hemagglitination titer from 1.15 to 0.84, 0.70 and 0.59 (P<0.01). In addition, different groups of FI could significantly lessen the mortality rate from 100% to 30%, 25% and 15%, and prolong the living time from 5.1d to 6.5d, 8.4d and 8.9d respectively(P<0.01). The high dose (75 mg/kg/d) has the similar effect with 100 mg/kg/d dose of virazole(P>0.05), and more effective than 200 mg/kg/d dose of antiviral liquor (P<0.05).  相似文献   
998.
Resistin, a small secretory molecule, has been implicated to play an important role in the development of insulin resistance under obese condition. For the past few decades, it has been linked to various cellular and metabolic functions. It has been associated with diseases like metabolic disorders, cardiovascular diseases and cancers. Numerous clinical studies have indicated an increased serum resistin level in pathological disorders which have been reported to increase mortality rate in comparison to low resistin expressing subjects. Various molecular studies suggest resistin plays a pivotal role in proliferation, metastasis, angiogenesis, inflammation as well as in regulating metabolism in cancer cells. Therefore, understanding the role of resistin and elucidating its’ associated molecular mechanism will give a better insight into the management of these disorders. In this article, we summarize the diverse roles of resistin in pathological disorders based on the available literature, clinicopathological data, and a compiled study from various databases. The article mainly provides comprehensive information of its role as a target in different treatment modalities in pre as well as post-clinical studies.  相似文献   
999.
Gut microbiome, as the largest and most important micro-ecosystem, plays a critical role in health. The purpose of this study was to evaluate whether heat stress modulates the composition and diversity of the gut microbiome in rats. The heat stress model was prepared in rats with the heating temperature maintained at 35–38°C. Cecum contents were collected after heat stress for 3 h and days 1, 3 and 7. Total DNA was extracted for 16 S rRNA sequencing and analysis of intestinal microbiome composition and diversity. The study showed that the composition of the intestinal microbiome of heat stress group was changed. And the heat stress modulated key phylotypes of gut microbiota at the level of phylum and genus. In particular, the genus of Lactobacillus and Bacteroides were significantly reduced, whereas the Oscillospira and Clostridium were increased by heat stress. Meanwhile, the rats under the heat stress encountered the change in carbohydrate metabolism, amino acid metabolism, and membrane transport to defense against stress. Taken together, the composition and structure of gut microbiome were affected by heat stress and some key phylotypes were also significantly altered. We conclude that the heat stress could impact multiple biological functions, via altering the gut microbiome.  相似文献   
1000.
Sex chromosome aberrations are known to cause congenital abnormalities and unexplained infertility in horses. Most of these anomalies remain undiagnosed because of the complexity of the horse karyotype and the lack of specialized laboratories that can perform such diagnoses. On the other hand, the utilization of microsatellite markers is a technique widely spread in horse breeding, mostly because of their usage in parentage tests. We studied the usage of a novel combination of diagnostic approaches in the evaluation of a very uncommon case of chromosomal abnormalities in a Spanish purebred colt, primarily detected using a commercial panel of short tandem repeat (STR) makers. Based on these results, we performed a full cytogenetic analysis using conventional and fluorescent in situ hybridization techniques with individual Equus caballus chromosome X and Equus caballus chromosome Y painting probes. We also tested the presence of two genes associated with the sexual development in horses and an extra novel panel of eight microsatellite markers specifically located in the sex chromosome pair. This is the first case report of a leukocyte chimerism between chromosomally normal (64,XY) and abnormal (63,X0) cell lines in horses. Our results indicate that the use of the short tandem repeat markers as a screening technique and as a confirmation utilizing cytogenetic techniques can be used as a very interesting, easy, and nonexpensive diagnostic approach to detect chromosomal abnormalities in the domestic horse.  相似文献   
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