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<p><b>OBJECTIVE</b>To study the effect of the polymorphism F279Y of the growth hormone receptor (GHR) gene on milk yield and composition in Chinese Holstein cattle.</p><p><b>METHODS</b>Hundred thirty two Chinese Holstein cattle were selected as study materials, according to DHI production performance method to get the data of milk yield and composition; PCR- SSCP and sequencing method were used to detect the genotypes; least square method was used to acquire correlation analysis.</p><p><b>RESULTS</b>Chinese Holstein cattle F279Y of GHR gene loci A and T allele frequency were 0.68 and 0.32, respectively, the experimental group significantly deviated from Hardy Weinberg equilibrium (P < 0.01); 305 d milk yield of AA genotype was significantly higher than AT type (P < 0.05), 305 d milk fat yield, 305 d milk protein yield and 305 d lactose of AT type had better trend than those of AA type in numeric; Therefore, allele A was dominant gene of high milk yield, allele T has positive effect on milk composition.</p><p><b>CONCLUSION</b>Mutation F279Y of GHR gene can be used as genetic markers in Chinese Holstein milk production traits of marker assisted selection (MAS) breeding.</p>
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Animaux , Bovins , Femelle , Génétique , Génotype , Lait , Sécrétions corporelles , Mutation ponctuelle , Récepteur STH , GénétiqueRésumé
Objective To observe the mechanical allodynia of affected extremity and the leakage of Evans blue when performing thermal stimulation on the threshold, and explore the efficacy of microwave on rats models of neuropathic pain and the optimum temperature and other ideal parameters for this treatment by performing microwave coagulation treatment under different temperatures to them.Methods Forty-two SD rats were induced the models of spared nerve injury (SNI) on sciatic nerves,then were equally randomized into 3 groups: control group (only inserting microwave coagulation needle but not heating), 42℃ microwave coagulation treatment group and 60℃ microwave coagulation treatment group (n=14). The 50% paw withdrawal threshold of the affected extremity was measured 1 d before and 1, 2, 4, and 6 weeks after treatment. The leakage of Evans blue in injured tissue of the affected extremity when performing thermal stimulation on the threshold was observed 2 weeks after treatment and compared between each 2 groups. Results The 50% paw withdrawal threshold was stable in control group, 42℃ microwave coagulation treatment group and 60℃ microwave coagulation treatment group 1 d before treatment; no significant differences were noted between each 2 groups (P>0.05). The 50% paw withdrawal threshold of 60℃ microwave coagulation treatment group 1, 2, 4, 6weeks after treatment was significantly increased as compared with that in the control group and 42℃microwave coagulation treatment group (P<0.05). The concentrations of leakage of Evans blue in the 42℃ microwave coagulation treatment group ([9.96±1.01] g/g) and 60℃ microwave coagulation treatment group ([7.41±1.37] g/g) were significantiy decreased as compared with those in the control group ([14.8±2.88] g/g, P<0.05). Conclusion Microwave coagulation can improve the mechanical hyperalgesia of in rats with neuropathic pain induced by SNI, and 60℃ is the proper temperature.Inflammation is inhibited by microwave coagulation and this might be one of the mechanisms to alleviate the pain.
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<p><b>OBJECTIVE</b>To study the effects of implantation brachytherapy with delayed-release particles of 32P-chromic phosphate-poly (L-lactide) (32P-CP-PLLA) on prostate cancer (PCa) in nude mice.</p><p><b>METHODS</b>We established a subcutaneous transplantable PCa model in nude mice, and randomly divided them into six groups, Groups A, B and C implanted intratumorally with 32P-CP-PLLA delayed-release particles at 3.7, 7.4 and 14.8 MBq, Groups D, E and F with 125I particles at the same doses as the former three, and another six nude mice were included in Group G as the blank control. Then we killed the mice at 21 days after the treatment, observed the effects of the particles on the morphology of the tumor and their inhibition of tumor growth, counted WBCs and platelets (PLTs) in the peripheral blood, and detected the toxic reaction of the blood.</p><p><b>RESULTS</b>At 21 days after the treatment, the solid tumor tissues exhibited bleeding and necrotic changes, and the rates of tumor inhibition were positively correlated with the doses of administration. Groups A, B and C showed statistically significant differences from Groups D, E, F and G in the rate of tumor inhibition ([ 65.72 +/- 6.95]%, [77.58 +/- 4.32]% and [82.64 +/- 4.03]% versus [35.61 +/- 5.61]%, [43.30 +/- 6.94]% and [69.01 +/- 4.98]%), WBC count ([1.72 +/- 0.37] x 10(9)/L, [1.23 +/- 0.27] x 10(9)/L and [0.86 +/- 0.25] x 10(9)/L versus [1.45 +/- 0.40] x 10(9)/L, [0.51 +/- 0.24] x 10(9)/L, [0.37 +/- 0.26] x 10(9)/L and [3.96 +/- 0.26] x 10(9)/L), PLT count ([1.18 +/- 0.11] x 10(11)/L, [0.97 +/- 0.10] x 10(11)/L and [0.72 +/- 0.11] x 10(11)/L versus [0.97 +/- 0.15] x 10(11)/L, [0.76 +/- 0.16] x 10(11)/L, [0.64 +/- 0.12] x 10(11)/L and [2.89 +/- 0.21] x 10(11)/L) and body weight ([18.60 +/- 0.66] g, [17.60 +/- 0.39] g and [16.90 +/- 0.68] g versus [17.86 +/- 0.60] g, [15.56 +/- 0.39] g, [14.61 +/- 0.65] g and [19.95 +/- 0.73] g) (P < 0.01).</p><p><b>CONCLUSION</b>Intratumoral implantation of 32P-CP-PL-LA is a safe, simple and effective radionuclide interventional therapy for prostate cancer.</p>
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Animaux , Mâle , Souris , Curiethérapie , Souris de lignée BALB C , Souris nude , Radio-isotopes du phosphore , Utilisations thérapeutiques , Tumeurs de la prostate , RadiothérapieRésumé
<p><b>OBJECTIVE</b>SK3, one of the small conductance calcium-activated potassium channels, is the key substance of the endothelium-derived hyperpolarizing factor (EDHF) passway. This study aimed to investigate the expression of SK3 in the cavernous tissue of rats with diabetes mellitus (DM).</p><p><b>METHODS</b>Twenty-six DM models were made by injection of streptozocin (STZ) out of 50 male Sprague-Dawley rats, and another 15 that failed to be modeled were included in an STZ group. Ten healthy male rats were taken as blank controls. Eight weeks later, the penile erectile function of the rats was detected by injection of apomorphine (APO) at 80 microg/kg, and the expression of SK3 in the cavernous tissue was determined by RT-PCR and Western blot.</p><p><b>RESULTS</b>Penile erection was observed in 14 (54%) of the 26 DM rat models and in all the rats of the STZ and blank control groups. Both the mRNA and protein expressions of SK3 were significantly lower in the DM (0.50 +/- 0.09 and 0.65 +/- 0.06) than in the STZ (1.15 +/- 0.03 and 1.28 +/- 0.04) and blank control groups (1.21 +/- 0.04 and 1.34 +/- 0.05) (P < 0.05). There were no significant differences between the STZ and blank control groups in either penile erection or mRNA and protein expressions of SK3 (P > 0.05).</p><p><b>CONCLUSION</b>Diabetes mellitus can significantly reduce erectile function in rats, which may be related to the decreased expression of SK3 in the corpus cavernosum.</p>
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Animaux , Mâle , Rats , Diabète expérimental , Métabolisme , Dysfonctionnement érectile , Métabolisme , Pénis , Métabolisme , Canaux potassiques calcium-dépendants , Métabolisme , ARN messager , Génétique , Rat Sprague-Dawley , Canaux potassiques calcium-dépendants de petite conductanceRésumé
<p><b>BACKGROUND</b>The relationship between signal transduction and tumors has become one of the foci in cancer research. Signal transducer and activator of the transcription 6 (STAT6) signaling pathway is found to be activated in some cancer cells. But the function of the pathway in cancer cells is unknown. This study was undertaken to investigate the effect of the Stat6 signaling pathway on apoptosis in human colon cancer cells (HT-29 cells) and the possible mechanism of Stat6 by RNA interference techniques.</p><p><b>METHODS</b>Four eukaryotic expression plasmid vectors of short hairpin RNA (shRNA) specific for the STAT6 gene were designed and generated by molecular biological technology. The plasmid vectors were transfected into HT-29 cells by cation liposomes to block the Stat6 signaling pathway. The expressions of STAT6 mRNA and phosph-Stat6 protein were detected by the reverse transcriptase polymerase chain reaction (RT-PCR) method and flow cytometry respectively to screen the most effective shRNA at 72 hours after transfection. The apoptosis condition of the cells in which the expression of the STAT6 gene had been interfered was analyzed by flow cytometry and confocal microscopy. Both mRNA and protein expression of B cell lymphoma-2 (Bcl-2) and Bax were detected by RT-PCR and western blotting.</p><p><b>RESULTS</b>Two effective eukaryotic expression plasmid vectors of shRNA specific for the STAT6 gene were generated successfully. One can reduce the expression of the STAT6 gene by 82.4% and the other by 56.8% (P < 0.01). The apoptotic rate of colon cancer cells in which STAT6 gene expression had been interfered was significantly higher than that in controlled colon cancer cells (P < 0.01). In the cells in which the Stat6 signaling pathway was blocked, the levels of mRNA and protein Bcl-2 were significantly decreased, whereas those of Bax were significantly increased (P < 0.01).</p><p><b>CONCLUSIONS</b>The Stat6 signaling pathway can inhibit apoptosis in human colon cancer cells. The subsequent disorder of Bcl-2/Bax expression may play an important part in that process. The STAT6 gene may serve as a potential target in cancer therapy.</p>
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Humains , Apoptose , Extinction de l'expression des gènes , Cellules HT29 , Plasmides , Protéines proto-oncogènes c-bcl-2 , Génétique , ARN messager , Petit ARN interférent , Pharmacologie , Facteur de transcription STAT-6 , Génétique , Transduction du signal , Protéine Bax , GénétiqueRésumé
96%).There are 14 nucleotide mutations between yak and cattle and 3 of that were predicted to alter the protein sequence,both of which occurred in the domain III.Construction of molecular phylogenetic tree shows:The cluster results coincided with the traditional taxonomy.
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<p><b>OBJECTIVE</b>Data on traffic accident from year 2000 to 2002 were collected and testified. Epidemiological study was carried out to find the main risk factors of traffic accident.</p><p><b>METHODS</b>The spatial distribution was conducted by means of Geographic Information System (GIS) and were marked on Shanghai digitalized map with different layers by different colors.</p><p><b>RESULTS</b>Results showed that during 2000, 2001 and 2002, 69,669 , 68,894, and 47,088 traffic accident episodes occurred in Shanghai, resulting in 1747, 1724, 1557 deaths respectively with direct economic lost: 2.1, 2.4, 3.0 billion RMB. The main risk factors causing traffic accident deaths would include drinking alcohol before driving, fatigue and speeding. The leading causes of death were head injury and complex injury of body. GIS showed that there was a homocentric circle with more traffic accidents in downtown city, but more deaths in the urban city. Disease burden caused by traffic accident was very heavy.</p><p><b>CONCLUSION</b>In Shanghai, traffic accident has great impact on social and economic issues thus should be controlled effectively. Focus should be layed on control of traffic accident in downtown area and to decrease the number of deaths related to traffic accident in the urban area.</p>
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Femelle , Humains , Mâle , Accidents de la route , Facteurs âges , Chine , Épidémiologie , Facteurs de risque , Facteurs sexuels , Plaies et blessures , ÉpidémiologieRésumé
(R)-chlorprenaline, a selective activator of beta2 receptor and an effective drug for bronchitis and asthma, is industrially prepared from (R)-2'-chloro-1-phenyl-ethanol. In this communication, we describe (1) the identification of Saccharomyces cerevisiae B5 as an effective host for stereoselective reduction of 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol; (2) the presence of ethanol enhances the conversion; and (3) the biochemical factors that effect the yield of the product. Among the four yeast strains capable of reduction 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol we screened, Saccharomyces cerevisiae B5 showed the highest activity and stereoselectivity, and was used for the subsequent study. The effect of the presence of methanol, ethanol, 2-propanol, 1-butanol, glucose, glycerol and lactic acid was first investigated, as it was previously reported that they increased the yield and stereoselectivity of the reaction. The addition of the co-substrate methanol, ethanol, 2-propanol, 1-butanol, glucose and glycerol favored the formation of the 2'-chloroacetophenone to (R)-2'-chloro-1-phenyl-ethanol. Lactic acid inhibited the enzyme activity. Ethanol is the best co-substrate among the seven co-substrates and under the optimum concentration of 5% , the yield of (R)-2'-chloro-1-phenyl-ethanol was increased from 17% to 74%. The oxidation of ethanol regenerates NADH required for the reduction. The effects of the reaction time, pH, cell concentration, substrate concentration and temperature on the reduction were investigated next. The enantiometric excess of (R)-2'-chloro-1-phenyl-ethanol reached 100% under the optimal condition: pH8.0, 25 degrees C and 5% ethanol. The product yield went up with the increasing Saccharomyces cerevisiae B5 concentration and reached 100% when the cell dry weight was 10.75 mg/mL and 2'-chloroacetophenone was 6.47 mmol/L. The yield of (R)-2'-chloro-1-phenyl-ethanol decreased sharply with the increase of substrate concentration, as the high concentration of substrates is toxic to the cell and inhibits the activity of reductases. The aerobic cultivation of the yeast and shaking during the reaction increased the yield of (R)-2'-chloro-1-phenyl-ethanol. The yeast can be reused up to 15 times. This research paves the way for economical preparation of chiral 2'-chloroacetophenone to R-2'-chloro-1-phenylethanol.