BACKGROUND:Retinoid X receptor (RXR) plays a central role in the regulation of intracellular receptor signaling pathways. The activation of RXR has protective effect on H2O2-induced apoptosis of H9c2 ventricular cells in rats. But the protective effect and mechanism of activating RXR in cardiomyocytes against hypoxia/reoxygenation (H/R)-induced oxidative iniury are stillunclear. METHODS:The model of H/R injury was established through hypoxia for 2 hours and reoxygenation for 4 hours in H9c2 cardiomyocytes of rats. 9-cis-retinoic acid (9-cis RA) was obtained as an RXR agonist, and HX531 as an RXR antagonist. Cultured cardiomyocytes were randomly divided into four groups:sham group, H/R group, H/R+9-cis RA -pretreated group (100 nmol/L 9-cis RA), and H/R+9-cis RA+HX531-pretreated group (2.5 μmol/L HX531). The cellviability was measured by MTT, apoptosis rate of cardiomyocytes by flow cytometry analysis, and mitochondrial membrane potential (ΔΨm) by JC-1 fluorescent probe, and protein expressions of Bcl-2, Bax and cleaved caspase-9 with Western blotting. Allmeasurement data were expressed as mean±standard deviation, and analyzed using one-way ANOVA and the Dunnett test. Differences were considered significant whenP was <0.05. RESULTS:Pretreatment with RXR agonist enhanced cellviability, reduced apoptosis ratio, and stabled ΔΨm. Dot blotting experiments showed that under H/R stress conditions, Bcl-2 protein level decreased, while Bax and cleaved caspase-9 were increased. 9-cis RA administration before H/R stress prevented these effects, but the protective effects of activating RXR on cardiomyocytes against H/R induced oxidative injury were abolished when pretreated with RXR pan-antagonist HX531. CONCLUSION:The activation of RXR has protective effects against H/R injury in H9c2 cardiomyocytes of rats through attenuating signaling pathway of mitochondria apoptosis.

Objective:To establish a method for measuring the activity of cornea epithelium quantitatively. Methods:Rabbit corneas were burnt either by alkali or by CO2 laser. The lamellar cornea was cut at the end of 1,2 and 3 weeks and cultured in 2 ml DMEM with 5% CO2, 37℃ for 1 h.Then 200 μl of MTT was added to the culture followed by incubation for another 4 h. The supernatant was discarded and 4 ml of DMSO was added into each culturedish for dissolving MTT completely under the condition of room temperature.200 μl of DMSO sample was added to each well of 96-well plate and each sample was triplicated. The absorbance of the plate was measured at 490 nm ultraviolet. Results:The D value of the burnt corneas was obviously lower than that of the normal ones(P<0.01). Conclusion:MTT method can be used to measure the activity of cornea epithelium quantitatively.

Objective To investigate plasma glutathione S-transferase(GSTs) activity and GSTP1 gene Ile105Val polymorphism in Bijie City, Guizhou Province, a coal-burning fluorosis endemic area. Methods One hundred and sixty villagers from Yachi Twon using non-improved cooking stoves were selected as the non-intervened group in Bijie City, Guizhou Province where coal-burning fluorosis was prevailing; 153 villagers as the intervented group were chosen from Changchun Twon, where cooking stoves were improved; 151 villagers were served as the control group from Baiyunshan Twon, Changshun County without endemic fluorosis. The activity of GSTs was tested by colorimetric analysis with spectrophotometer. The genotype of the GSTP1 gene Ile105Val polymorphism, presenting as either homozygous wild-type (AA), or heterozygous mutation type (AG), or homozygous mutation type (GG), was detected through the PCR-RFLP procedure. Results The activity of GSTs in plasma of non-intervened group [(12.44±4.97) kU/L]was significantly lower than that of intervened group (P < 0.05), and that of intervened group[(20.78±6.20)kU/L]was significantly lower than that of control group[(24.30±6.27)kU/L, P< 0.05]. The difference of the enzyme activity of three groups were statistically significant (F = 51.71, P < 0.05), but this enzyme activity did not vary significantly in each sex of each grnup(P > 0.05). Compared intervened group [AA:67.3%(103/153), AG:29.4%(45/153),GG:3.3%(5/153)]and non-intervened group[AA:66.9%(107/160), AG:30%(48/160), GG:3.1%(5/160)]with control group[AA:74.8%(113/151), AG:25.2%(38/151), GG:0 (0/151)], the Ile105Val polymorphism site of GSTP1 gene had significant difference(χ2= 6.04,6.07, both P< 0.05), but not significant between intervened and non-intervened groups(χ2 = 0.02, P>0.05). Conclusions Fluorosis can decrease the activity of GSTs and introduce the GSTP1 gene Ile105Val polymorphism, intervention with the fluorine intake will improve the effect of fluoride on the body.

AIMTo investigate the effects of shivering on airway rewarming.

METHODSThe hypothermic dog model without shivering was established by immersing an anesthetized dog in cold water and administering atracurium to inhibit the dog shivering. The model dog respired warm fully humidified (40-45 degrees C, RH 99.9%) air and room temperature air(19 +/- 1 degrees C, RH 30% - 75%) to rewarm each for 2 hours, the priority of different temperature air respired was arranged randomly. After rewarming for 4 hours, the relaxed dog breathed warm humidified air by positive pressure ventilation in order to restore its spontaneous respiratory. Then the dog continued to respire warm humidified air spontaneously until the esophageal (Te) and rectal temperature (Tr) of the dog achieved the same degrees as the dog was immersed in the water. The metabolic heat production was detected by indirect calorimetry during the experiment.

RESULTS(1) When the shivering was inhibited, inhaling warm humidified air for 2 hours made the Tr and Te of the dogs increase 0.26-0.39 degrees C and 0.44-1.11 degrees C per hour respectively, inhaling air at room temperature for 2 hours made Tr and Te of the dogs decrease 0.24-0.51 degrees C and 0.58-0.67 degrees C per hour, respectively. And the changes in Tr and Te of the dogs were unrelated to the priority of inhaling air at different temperature. (2) When the dog with shivering respired spontaneously warm humidified air, the rewarming rates of Tr and Te were 2.26-2.33 degrees C/h and 1.96-2.38 degrees C/h respectively, quicker than those of the dogs whose shivering was inhibited. (3) Compared with metabolic heat production of the unshivering dog respiring warm humidified air by positive pressure ventilation, that of the shivering dog respiring warm humidified air spontaneously increased outstandingly, shivering thermogenesis made the rewarming rates increased obviously.

CONCLUSIONAirway rewarming is a method conducive to rewarming of hypothermia. When the body is shivering, the metabolic heat production increases obviously, that makes the rewarming rate increase markedly. So the shivering must be inhibited in order to eliminate the interference of shivering thermogenesis when the effects of airway rewarming are detected.

Animals ; Body Temperature Regulation ; Cold Temperature ; Dogs ; Hypothermia ; physiopathology ; therapy ; Hypothermia, Induced ; Male ; Respiratory Physiological Phenomena ; Shivering

This study is to evaluate the therapeutic effect of fibroblast growth factor 21 (FGF21) on type 2 diabetic mice model and to provide mechanistic insights into its therapeutic effect. Type 2 diabetic animal model was established with high calorie fat diet and low dose streptozotocin (STZ) injection. Mice were then randomized into 5 groups: model control, FGF21 0.25 and 0.05 μmol x kg(-1) x d(-1) groups, insulin treatment group. Ten age-matched normal KM mouse administered with saline were used as normal controls. Serum glucose, insulin, lipid products and the change of serum and liver tissue inflammation factor levels between five groups of mouse were determined. The results showed that blood glucose, insulin, free fatty acids (FFAs), triglycerides, and inflammatory factor average FGF-21 of type 2 diabetes model group and normal control group were significantly higher (P < 0.01), while compared with insulin group, no difference was significant. Average blood glucose, insulin, blood lipid and inflammatory factor of FGF-21 treatment group compared with type 2 diabetes group was significantly lower (P < 0.01) and insulin group has no difference with the model control group. The results of OGTT and HOMA-IR showed that insulin resistance state was significantly relieved in a dose-dependent manner. Thus, this study demonstrates that FGF-21 significantly remits type 2 diabetic mice model's insulin resistance state and participates in the regulation of inflammatory factor levels and type 2 diabetes metabolic disorders.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental ; drug therapy ; Diabetes Mellitus, Type 2 ; drug therapy ; Diet, High-Fat ; Fatty Acids, Nonesterified ; blood ; Fibroblast Growth Factors ; pharmacology ; Insulin ; blood ; Insulin Resistance ; Mice ; Streptozocin ; Triglycerides ; blood

OBJECTIVETo investigate the effect of enhanced nutritional therapy on wound healing after endoscopic therapy in patients with liver cirrhosis and esophageal varices.

METHODSFifty patients with liver cirrhosis and esophageal varices were randomly divided into an enhanced nutritional therapy group (n = 25) and a control group (n = 25). The enhanced nutritional therapy group received one week of enhanced nutritional supplementation, including liver nutritional elements, prior to routine endoscopic therapy. The routine without any change to their diet. The rate of transformation and status of wound healing of esophageal varices were compared between the two groups.

RESULTSThe ratio of ulcers occurring at the injection site was lower in the enhanced nutrition group than in the control group (16/25 vs. 23/25; x2 = 5.711, P = 0.017). The enhanced nutrition group had only one case of minimal bleeding occurring during endoscopy as compared to the seven cases of bleeding in the control group (x2 = 5.357, P = 0.021). On average, the enhanced nutrition group required less sessions of endoscopic treatment to achieve eradication of esophageal varices than the control group (3.8 vs. 4.1; t = 2.069, P = 0.044).

CONCLUSIONPre-endoscopic enhanced nutritional therapy may benefit patients with liver cirrhosis and esophageal varices by promoting recovery of procedure-related local tissue injury and occlusion of varices.

Adult ; Endoscopy ; Esophageal and Gastric Varices ; etiology ; therapy ; Female ; Humans ; Liver Cirrhosis ; complications ; therapy ; Male ; Middle Aged ; Nutritional Support ; Wound Healing

BACKGROUNDThe long-term effects of bone marrow-derived cells (BMC) transplantation in patients with acute myocardial infarction (AMI) have not been established. The present meta-analysis of randomized controlled trials with follow-up ≥ 2 years was performed to investigate the long-term effects of BMC therapy in patients after AMI.

METHODSSpecific terms were used to conduct a systematic literature search of MEDLINE, EMBASE, the Cochrane Library and the Cochrane Central Register of Controlled Trials, and the China Biological Medicine Disk database from their inception to March 2012. A standardized protocol was used to extract information, and random effect model was used to analyze all data except major adverse events.

RESULTSFive trials comprising 510 patients were included. Compared with controls, BMC therapy significantly improved left ventricular ejection fraction (LVEF) (4.18%, 95%CI: 2.02% to 6.35%, P = 0.0002), while mildly but not significantly reduced left ventricular end-systolic volume (-4.47 ml, 95%CI: -10.92 to 1.99, P = 0.17) and left ventricular end-diastolic volume (-2.29 ml, 95%CI: -9.96 to 5.39, P = 0.56). Subgroup analysis revealed that significant improvement of LVEF induced by BMC therapy could be observed in patients with baseline LVEF ≤ 42%, but disappeared in those with baseline LVEF > 42%. There were trends in favor of BMC therapy for most major clinical adverse events, though most differences were not significant.

CONCLUSIONSIntracoronary BMC infusion in patients with AMI seems to be safe and may further improve LVEF on top of standard therapy; especially the beneficial effects could last for long term. The findings need to be validated in the future.

Acute Disease ; Bone Marrow Transplantation ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; physiopathology ; surgery ; Randomized Controlled Trials as Topic ; Ventricular Function, Left

OBJECTIVEUsing chitosan (CS)/beta-tricalcium phosphate (TCP)/recombinant human bone morphogenetic protein (rhBMP)-2 for the reconstruction of rabbits' mandible defect, to prove the feasibility of CS/beta-TCP as an injectable bone tissue engineering scaffold material.

METHODSTwenty-four New Zealand white rabbits were randomized into 4 groups on average: Experimental group 1 embedding CS/beta-TCP/rhBMP-2, experimental group 2 embedding CS/ beta-TCP, control group 1 embedding autograft bone group, control group 2 embedding nothing. At 2, 4 and 8 weeks after surgery, all rabbits were executed group by group. The new bone growth situations were observed with hematoxylin-eosin staining and immunofluorescence microscopy, the bone mineral density was detected by bone sonometers.

RESULTSAfter 2, 4, 8 weeks, there was significant difference among the areas of bone regeneration of all groups. The effect of experimental group 1 was better than experimental group 2. There was significant difference at different times, the areas of bone regeneration was gradually increased with time. The area of stained yellow in experimental group 1 was larger, the area of stained red was smaller. The quantities of bone density in experimental group 1 at every time after surgery were significantly higher than experimental group 1 and control group 2, but had no statistical significance with control group 1.

CONCLUSIONCS/beta-TCP/rhBMP-2 has good biocompatibility, degradability and the capacity of guided and inducing osteogenesis. CS/beta-TCP as a good injection of carrier could become a promising carrier for rhBMP-2 and potential new degradable biological material for repairing bone defect in clinical application.

Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; Bone Regeneration ; Bone Transplantation ; Bone and Bones ; Calcium Phosphates ; Chitosan ; Humans ; Osteogenesis ; Rabbits ; Recombinant Proteins ; Tissue Engineering ; Tissue Scaffolds ; Transforming Growth Factor beta

Objective To explore the relationship between -262C/T and -21A/T polymorphisms of catalase(CAT) gene and coal-burning borne fluorosis. Methods In 2007, 150 villagers were taken as a nonintervention group in Bijie city from the village of coal-burning borne fluorosis areas with unchanged cooking stoves;150 villagers were taken as the intervention group from the town of Changchun county where cooking stoves changed; 150 villagers were taken as control from non-endemic fluorosis areas in Baiyun town of Changshun county.PCR-restriction fragment length polymorphism were employed to detect genotypes of CAT-262C/T and CAT-21A/T polymorphism of CAT gene. Results The genotypic frequencies of CAT-262C/T and CAT-21A/T in nonintervention group,intervention group and control group were in line with Hardy-Weinberg equilibrium law (P＞ 0.05 ).The genotypes of CC and CT were detected while no TT were detected for CAT-262C/T polymorphism; the genotypes of AA, AT and TT were detected for CAT-21A/T. The genotype frequencies of CAT-262 CC, CT in control group, intervention group and non-intervention group were (89.33%(134/150), 10.67%(16/150); 88.67%(133/150), 11.33% (17/150),93.33% (140/150),6.67% (10/150), respectively. The gene frequency of C in control group, intervention group and non-intervention group were (94.67% (284/300), 94.33% (283/300),96.67%(290/300), respectively. The gene frequency of T in control group, intervention group and non-intervention group were 5.33%(16/300), 5.67%(17/300), 3.33%(10/300), respectively. The genotype frequencies of CAT-21 AA,AT and TT in control group, intervention group and non-intervention group were 48.67%(73/150),46.00%(69/150),5.33%(8/150) ,52.67%(79/150) ,38.00%(57/150) ,9.33% (14/150) ,51.33%(77/150) ,38.00%(57/150), 10.67%(16/150), respectively. The gene frequency of A in control group, intervention group and non-intervention group were 71.67%(215/300),71.67%(215/300),70.33%(211/300), respectively. The gene frequency of T in control group, intervention group and non-intervention group were 28.33% (85/300),28.33% (85/300),29.67% (89/300),respectively. CAT-262C/T and CAT-21A/T genotype and allele frequencies in the control group, the intervention group and non-intervention group showed no significant differences in the distribution(x2= 0.331,0.336, all P ＞0.05 ). Conclusion CAT-262C/T and CAT-21A/T polymorphism is not associated with coal-burning borne fluorosis.

ObjectiveTo observe the distribution of vitamin D receptor(VDR) gene polymorphisms in coal-burning borne fluorosis in Guizhou province and investigate the relationship between VDR gene polymorphisms and the susceptibility to coal-burning borne fluorosis.MethodsOne hundred and fifty villagers from non-improving cooking stove villages were selected as a non-intervention group in Bijie area,Guizhou province where coal-burning borne fluorosis was prevailing; 150 villagers were chosen from cooking stove improved villages as a intervention group; 150 villagers were selected from non-endemic area Changshun county as a control group.DNA was extracted from peripheral blood samples of these people.Genotype of VDR gene Bsm Ⅰ and Fok Ⅰ loci were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).ResultsDistribution of Bsm Ⅰ polymorphism site of VDR gene of control group [AA:19.3％ (29/150),AG:39.3％ (59/150),GG:41.3％(62/150)],was compared with that[AA:4.7％(7/150),AG:14.0％(21/150),GG:81.3％(122/150)] of the non-intervention group and that[AA:7.3％(11/150),AG:23.3％(35/150),GG:69.3％(104/150)] of intervention group,and the difference was statistically significant(X2 =56.6,P ＜ 0.05).The frequency of VDR-Fok Ⅰ loci in non-intervention group [TT:29.3％(44/150),TC:55.3％(83/150),CC:15.3％(23/150)] and intervention group [TT:32.7％(49/150),TC:55.3％(83/150),CC:12.0％(18/150)] was compared with that [TT:45.3％(68/150),TC:48.7％(73/150),CC:6.0％(9/150)] of control group,and the difference was statistically significant(X2 =11.9,P ＜ 0.05).Univariate analysis showed that individuals carrying the GG genotype had increased risk of suffering fluorosis than individuals carrying the AA and AG genotypes(OR values were 6.2,3.2,all P ＜ 0.05),while carrying the TC and CC genotype had increased risk of suffering fluorosis than individuals carrying the TT genotype (OR values were 1.3,2.8,1.3,2.1,all P ＜ 0.05).ConclusionVDR gene polymorphisms may be one of the predisposing factors of coal-burning borne fluorosis.