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1.
To study the gene expression profiles between immunologically injured liver cell and normal liver cell of mice and to screen
on a large scale the differentially expressed genes associated with the formation of liver injury, the experimental mice were
randomly divided into the normal group for controlling and the immunologically liver-injured group induced by BCG and LPS.
The liver mRNA of the two groups were extracted respectively and reversely-transcribed to cDNA with the incorporation of different
fluorescence (Cy3, Cy5) labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarray
chips. The fluorescent signal results were acquired by scanner ScanArray 4000 and analyzed with software GenePix Pro 3.0.
Among the 14112 target genes, 293 genes were found to be significantly differentially expressed, in which 188 genes were up-regulated
and 105 genes were down-regulated. Based on the analysis of biological functions of those differentially expressed genes,
it was indicated that the occurrence and development of mouse liver damage induced by BCG and LPS were highly correlated with
the processes of immune reactions, cell synthesis, metabolism, apoptosis and transportation in liver cell, which might be
quite important for elucidating the regulatory network of gene expression associated with the liver damage, also important
for finally discovering the pathogenic mechanisms of immunological liver damage. 相似文献
2.
3.
Liang A Sha J Lu W Chen M Li L Jin D Yan Y Wang J Ping S Zhang W Wang Y Lin M 《Biotechnology letters》2008,30(8):1397-1401
A novel class II 5-enoylpyruvylshikimate-3-phosphate synthase (EPSPS) was identified from Pseudomonas stutzeri A1501 by complementation of an Escherichia coli auxotrophic aroA mutant. The single amino acid substitution of serine (Ser) for asparagine (Asn)-130 of the A1501 EPSPS enhanced resistance to 200 mM glyphosate. The mutated EPSPS had a 2.5-fold increase for IC(50) [glyphosate] value, a 2-fold increase for K (i) [glyphosate] value, but a K (m) [PEP] value similar to that of wild type. The effect of the single residue mutation on glyphosate resistance was also analyzed using a computer-based three-dimensional model. 相似文献
4.
Li Ming Wei Fuwen Huang Chengming Pan Ruliang de Ruiter Johannes 《International journal of primatology》2004,25(4):861-873
Snub-nosed monkeys (Rhinopithecus spp.) are confined to isolated mountainous regions in China and North Vietnam. Their systematic classification and phylogenetic relationship has been controversial. The structures of mitochondrial DNA cytochrome b and 12S rRNA show that the 4 species of Rhinopithecus are quite different from other colobines. It is reasonable to regard them as an independent genus, as determined by external features, morphometric characters and behavior. However, whether or not there should be a subdivision between the Vietnamese and Chinese species at the subgeneric level remains to be clarified; more evidence from a large range of Asian colobine species is needed. The Guizhou species, Rhinopithecus brelichi, is a valid species, which is more closely related to Pygathrix than the other species ( R. roxellana, R. bieti and R. avunculus) are. Results also indicate that 3 species—Rhinopithecus roxellana, R. bieti and R. avunculus—might have diverged from R. brelichi, but the phylogenetic relationship of R. avunculus is not clear. 相似文献
5.
The present study was designed to characterize pharmacological, biophysical and electrophysiological properties of the recombinant
human cardiac I
Ks (KCNQ1/KCNE1) channels at physiological temperature. Human cardiac KCNQ1 and KCNE1 genes were cotransfected into HEK 293 cells, and a cell clone stably expressing both genes was selected. Membrane currents
were recorded using a perforated patch-clamp technique. The typical I
Ks was slowly activated upon depolarization voltages in HEK 293 cells stably expressing human cardiac KCNQ1 and KCNE1 genes, and the current was inhibited by I
Ks blockers HMR 1556 and chromanol 293B, with 50% inhibitory concentrations (IC50s) of 83.8 nM and 9.2 μM, respectively. I
Ks showed a significant temperature-dependent increase in its magnitude upon elevating bath temperature to 36°C from room temperature
(21°C). The current was upregulated by the β-adrenoceptor agonist isoproterenol, and the effect was reversed by H89. In addition,
I
Ks was inhibited by Ba2+ in a concentration-dependent manner (IC50 = 1.4 mM). Action potential clamp revealed a “bell-shaped” time course of I
Ks during the action potential, and maximal peak current was seen at the plateau of the action potential. A significant use-
and frequency-dependent increase of I
Ks was observed during a train of action potential clamp. These results indicate that the recombinant human cardiac I
Ks stably expressed in HEK 293 cells is similar to native I
Ks in drug sensitivity and regulated by Ba2+ and β-adrenoceptor via the cyclic adenosine monophosphate/protein kinase A pathway. Importantly, the current exhibits significant
temperature dependence, a bell-shaped time course during action potential and prominent use- or frequency-dependent accumulation
during a train of action potentials. 相似文献
6.
7.
Zhang M Xu YJ Saini HK Turan B Liu PP Dhalla NS 《American journal of physiology. Heart and circulatory physiology》2005,289(2):H832-H839
Although pentoxifylline (PTXF), a phosphodiesterase inhibitor, has been reported to exert beneficial effects in cardiac bypass surgery, its effect and mechanisms against ischemia-reperfusion (I/R) injury in heart are poorly understood. Because I/R is known to increase the level of tumor necrosis factor (TNF)-alpha in myocardium and PTXF has been shown to depress the production of TNF-alpha in failing heart, this study examined the hypothesis that PTXF may attenuate cardiac dysfunction and reduce TNF-alpha content in I/R heart. For this purpose, isolated rat hearts were subjected to global ischemia for 30 min followed by reperfusion for 2-30 min. Although cardiac dysfunction due to ischemia was not affected, the recovery of heart function upon reperfusion was markedly improved by PTXF treatment. This cardioprotective effect of PTXF was dose dependent; maximal effect was seen at a concentration of 125 microM. TNF-alpha, nuclear factor-kappaB (NF-kappaB), and phosphorylated NF-kappaB contents were decreased in ischemic heart but were markedly increased within 2 min of starting reperfusion. The ratio of cytosolic-to-homogenate NF-kappaB was decreased, whereas the ratio of particulate-to-homogenate NF-kappaB was increased in I/R hearts. These changes in TNF-alpha and NF-kappaB protein contents as well as in NF-kappaB redistribution due to I/R were significantly attenuated by PTXF treatment. The results of this study indicate that the cardioprotective effects of PTXF against I/R injury may be due to reductions in the activation of NF-kappaB and the production of TNF-alpha content. 相似文献
8.
This study evaluates the effect of control factors on cryopreservation of articular cartilage chondrocytes using the Taguchi method. Freeze-thaw experiments based on the L8(27) two-level orthogonal array of the Taguchi method are conducted, and ANOVA (analysis of variables) is adopted to determine the statistically significant control factors that affect the viability of the cell. Results show that the type of cryoprotectant, freezing rate, thawing rate, and concentration of cryoprotectant (listed in the order of influence) are the statistically significant control factors that affect the post-thaw viability. The end temperature and durations of the first and second stages of freezing do not affect the post-thaw viability. Within the ranges of the control factors studied in this work, the optimal test condition is found to be a freezing rate of 0.61 ± 0.03 °C/min, a thawing rate of 126.84 ± 5.57 °C/min, Me2SO cryoprotectant, and a cryoprotectant concentration of 10% (v/v) for maximum cell viability. In addition, this study also explores the effect of cryopreservation on the expression of type II collagen using immunocytochemical staining and digital image processing. The results show that the ability of cryopreserved chondrocytes to express type II collagen is reduced within the first five days of monolayer culture. 相似文献
9.
The objective was to develop a high-throughput method of identifying sex in both Coturnix chinensis and Gallus gallus, which would be useful for biomedical research and hatcheries. Because chromo-helicase-DNA binding protein (CHD)-based Griffiths P2/P8 primers do not produce polymerase chain reaction (PCR) products with distinguishable sex-specific curves in melting curve analysis (MCA), these primers are unsuitable for high throughput application in either species. Conserved regions were identified by basic local alignment search tool (BLAST) analyses of cloned CHD-Z and CHD-W genes of C. chinensis. Based on sequence alignment, a female-specific CHD-W primer (W-cot-F1) and a female/male (or CHD-W/CHD-Z)-common primer (ZW-cot-F1) were redesigned for use in combination with the Griffiths P2 primer for MCA-based PCR reaction. In C. chinensis and G. gallus, W-cot-F1/P2 and ZW-cot-F1/P2 had amplicon lengths of 315/318 and 114 base pairs and melting temperatures (Tm) of approximately 79.5 °C to 80 °C and approximately 78.5 °C to 79°C, respectively. Thus, MCA distinguished sex based on two distinct Tm peaks in females versus only one Tm peak in males. The MCA-based real-time PCR combined with the proposed primer redesign provided a high-throughput method of identifying sex in C. chinensis and G. gallus. 相似文献
10.
Bilal Chughtai Richard Lee Jaspreet Sandhu Alexis Te Steven Kaplan 《Reviews in urology》2013,15(2):61-66
Postprostatectomy incontinence (PPI) is a bothersome complication of radical prostatectomy. Although most men recover from PPI, some men continue to have persistent urinary incontinence. The initial management of persistent PPI usually consists of conservative measures such as pelvic floor muscle exercises. Surgical treatments are usually not entertained for men with urinary incontinence until conservative treatments have failed. This article discusses risk factors for PPI and various options for its treatment, including biofeedback and pharmacotherapy.Key words: Postprostatectomy incontinence, Radical prostatectomy, Pelvic floor muscle training, Pelvic floor stimulationPostprostatectomy incontinence (PPI) is a bothersome complication of radical prostatectomy (RP). Although most men recover from PPI, some men continue to have persistent urinary incontinence and roughly half of these men seek treatment.1 It is important to understand the natural history of postprostatectomy urinary dysfunction prior to initiating treatment. Generally, the initial management of persistent PPI consists of conservative measures such as pelvic floor muscle exercises. 相似文献