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11.
Multiplex Pyrosequencing   总被引:5,自引:2,他引:3       下载免费PDF全文
We describe here the development of a new and simple single-tube multiplex Pyrosequencing assay. Genomic DNA or cDNA was employed to PCR amplify region(s) using biotinylated and normal primer(s). Subsequent to capture of PCR products on streptavidin-coated beads, single-stranded DNA separation and hybridization of multiple sequencing primers, Pyrosequencing was performed. The obtained pyrogram resulted in a unique pattern in which the intensity of the signal determined the number of incorporated nucleotide(s). Here, we demonstrate the use of this multiplex Pyrosequencing for single nucleotide polymorphisms genotyping and microbial typing.  相似文献   
12.
Prostate cancer (PCa) is the second most common cancer in men. Androgen deprivation therapy (ADT) leads to tumor involution and reduction of tumor burden. However, tumors eventually reemerge that have overcome the absence of gonadal androgens, termed castration resistant PCa (CRPC). Theories underlying the development of CRPC include androgen receptor (AR) mutation allowing for promiscuous activation by non-androgens, AR amplification and overexpression leading to hypersensitivity to low androgen levels, and/or tumoral uptake and conversion of adrenally derived androgens. More recently it has been proposed that prostate tumor cells synthesize their own androgens through de novo steroidogenesis, which involves the step-wise synthesis of androgens from cholesterol. Using the in vivo LNCaP PCa xenograft model, previous data from our group demonstrated that a hypercholesterolemia diet potentiates prostatic tumor growth via induction of angiogenesis. Using this same model we now demonstrate that circulating cholesterol levels are significantly associated with tumor size (R = 0.3957, p = 0.0049) and intratumoral levels of testosterone (R = 0.41, p = 0.0023) in LNCaP tumors grown in hormonally intact mice. We demonstrate tumoral expression of cholesterol uptake genes as well as the spectrum of steroidogenic enzymes necessary for androgen biosynthesis from cholesterol. Moreover, we show that circulating cholesterol levels are directly correlated with tumoral expression of CYP17A, the critical enzyme required for de novo synthesis of androgens from cholesterol (R = 0.4073, p = 0.025) Since hypercholesterolemia does not raise circulating androgen levels and the adrenal gland of the mouse synthesizes minimal androgens, this study provides evidence that hypercholesterolemia increases intratumoral de novo steroidogenesis. Our results are consistent with the hypothesis that cholesterol-fueled intratumoral androgen synthesis may accelerate the growth of prostate tumors, and suggest that treatment of CRPC may be optimized by inclusion of cholesterol reduction therapies in conjunction with therapies targeting androgen synthesis and the AR.  相似文献   
13.

Background

Erythropoiesis is regulated by a range of intrinsic and extrinsic factors, including different cytokines. Recently, the role of catecholamines has been highlighted in the development of erythroid cell lineages.

Objective

This study focuses on the biological links interconnecting erythroid development and the sympathetic nervous system. The emerging evidence that underscores the role of catecholamines in the regulation of erythropoietin and other erythropoiesis cytokines are thoroughly reviewed, in addition to elements such as iron and the leptin hormone that are involved in erythropoiesis.

Methods

Relevant English-language studies were identified and retrieved from the PubMed search engine (1981–2017) using the following keywords: “Erythropoiesis”, “Catecholamines”, “Nervous system”, and “Cytokines.”

Results

Chronic social stress alters and suppresses erythroid development. However, the physiological release of catecholamines is an additional stimulator of erythropoiesis in the setting of anemia. Therefore, the severity and timing of catecholamine secretion might distinctly regulate erythroid homeostasis.

Conclusion

Understanding the relationship of catecholamines with different elements of the erythroid islands will be essential to find the tightly regulated production of red blood cells (RBCs) in both chronic and physiological catecholamine activation.
  相似文献   
14.
Diarrhea is considered as an important cause of morbidity and mortality, even though one of the main reasons of death following diarrhea is initiated by dysentery. In recent years, the consumption of probiotics has been proposed for the treatment of infectious diarrhea. Despite most of the studies on probiotics have focused on acute watery diarrhea, few studies in the field of dysentery have found beneficial effects of probiotics. This study is a randomized double-blind clinical trial. The patients were randomly placed into control and case groups. In the intervention group, the patients received probiotics in the form of Kidilact® sachet, which contained high amounts of 7-strain friendly bacteria strains of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium infantis, Bifidobacterium breve, and Streptococcus thermophiles. On the other hand, the patients in the control group received placebo sachets on a daily basis for 5 days. It is notable that the treatment protocol of acute dysentery was done on both groups. The results of this study showed significant differences in the duration of blood in diarrhea between probiotic consumers (2.62 days) and the control group (3.16 days) (P value = 0.05). Additionally, significant differences in the average length of hospitalization in probiotic consumers (3.16 days) and control (3.66 days), (P value = 0.02) could be claimed that the consumption of probiotics is effective in reducing the duration of dysentery and diarrhea. The results of this study suggest that the use of probiotics can be effective in reducing the duration of blood in diarrhea. This study was also recorded in the Iran center of clinical trials registration database (IRCT2014060617985N1).  相似文献   
15.

Background  

Complex networks are studied across many fields of science and are particularly important to understand biological processes. Motifs in networks are small connected sub-graphs that occur significantly in higher frequencies than in random networks. They have recently gathered much attention as a useful concept to uncover structural design principles of complex networks. Existing algorithms for finding network motifs are extremely costly in CPU time and memory consumption and have practically restrictions on the size of motifs.  相似文献   
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In this study Saccharomyces cerevisiae yeast cells was used as a novel vehicle for encapsulation of vitamin D3. The effects of initial cholecalciferol concentration (100,000 and 500,000 IU/g yeast), yeast cell pretreatment (plasmolysis with NaCl) and drying method (spray or freeze drying) on microcapsules properties were investigated. It was found that the vitamin concentration and drying method had significant influence on encapsulation efficiency (EE) and size of yeast microcapsules. Furthermore, EE values were more increased by the plasmolysis treatment. The highest EE was obtained for plasmolysed and spray dried yeast cells prepared using initial cholecalciferol concentration of 2.5 mg per gram of yeast cells (76.10?±?6.92%). The values of mean particle size were 3.43–7.91 μm. The presence of cholecalciferol in yeast microcapsules was confirmed by X-ray diffraction (XRD) and Fourier transform-infrared (FT-IR) analyses. The in vitro cholecalciferol release from yeast microcapsules in phosphate buffer saline solution (PBS) followed a controlled release manner consistent with a Fickian diffusion mechanism. In addition, the release studies in simulated gastrointestinal tract showed sustained release of cholecalciferol in the stomach condition and significant release in intestinal medium.  相似文献   
18.
This study comparatively investigated the effectiveness of calcium and other well‐known inducers such as isobutylmethylxanthine (IBMX) and insulin in differentiating human adipose‐derived stem cells (ADSCs) into neuronal‐like cells. ADSCs were immunophenotyped and differentiated into neuron‐like cells with different combinations of calcium, IBMX, and insulin. Calcium mobilization across the membrane was determined. Differentiated cells were characterized by cell cycle profiling, staining of Nissl bodies, detecting the gene expression level of markers such as neuronal nuclear antigen (NeuN), microtubule associated protein 2 (MAP2), neuron‐specific enolase (NSE), doublecortin, synapsin I, glial fibrillary acidic protein (GFAP), and myelin basic protein (MBP) by quantitative real‐time polymerase chain reaction (quantitative real‐time polymerase chain reaction (qRT‐PCR) and protein level by the immunofluorescence technique. Treatment with Ca + IBMX + Ins induced neuronal appearance and projection of neurite‐like processes in the cells, accompanied with inhibition of proliferation and halt in the cell cycle. A significantly higher expression of MBP, GFAP, NeuN, NSE, synapsin 1, doublecortin, and MAP2 was detected in differentiated cells, confirming the advantages of Ca + IBMX + Ins to the other combinations of inducers. Here, we showed an efficient protocol for neuronal differentiation of ADSCs, and calcium fostered differentiation by augmenting the number of neuron‐like cells and instantaneous increase in the expression of neuronal markers.  相似文献   
19.
Scaffold‐based tissue engineering is considered as a promising approach in the regenerative medicine. Graft instability of collagen, by causing poor mechanical properties and rapid degradation, and their hard handling remains major challenges to be addressed. In this research, a composite structured nano‐/microfibrous scaffold, made from a mixture of chitosan–ß‐glycerol phosphate–gelatin (chitosan–GP–gelatin) using a standard electrospinning set‐up was developed. Gelatin–acid acetic and chitosan ß‐glycerol phosphate–HCL solutions were prepared at ratios of 30/70, 50/50, 70/30 (w/w) and their mechanical and biological properties were engineered. Furthermore, the pore structure of the fabricated nanofibrous scaffolds was investigated and predicted using a theoretical model. Higher gelatin concentrations in the polymer blend resulted in significant increase in mean pore size and its distribution. Interaction between the scaffold and the contained cells was also monitored and compared in the test and control groups. Scaffolds with higher chitosan concentrations showed higher rate of cell attachment with better proliferation property, compared with gelatin‐only scaffolds. The fabricated scaffolds, unlike many other natural polymers, also exhibit non‐toxic and biodegradable properties in the grafted tissues. In conclusion, the data clearly showed that the fabricated biomaterial is a biologically compatible scaffold with potential to serve as a proper platform for retaining the cultured cells for further application in cell‐based tissue engineering, especially in wound healing practices. These results suggested the potential of using mesoporous composite chitosan–GP–gelatin fibrous scaffolds for engineering three‐dimensional tissues with different inherent cell characteristics. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 163–175, 2016.  相似文献   
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