Background The domestic and international researches discovered that many proteins and enzymes of the extracellular matrix (ECM) participate in the sclera remodeling by affecting the collagen typeⅠand fibronectin.Objective This study was to investigate the effect of matrixmetalloproteinase-2 (TIMP-2) on expression of collagen typeⅠand fibronectin of ECM in the posterior sclera by injecting liposomes containing tissue inhibitor of TIMP-2 gene into suprachoroidal space of the form-deprivation myopia in guinea pig.Methods Form-deprivation myopia was induced by translucent goggles in 36 clean guinea pig for 2 weeks.Then the animals were randomly assigned to TIMP-2 group,empty plasmid group,saline group and 12 for each group.Liposomes of 5μl containing TIMP-2 gene,empty plasmid and saline were suprachoroidally injected in the right eye respectively,and the left eyes without any treatment were used as self-control group.Other 12 matched guinea pigs only covered the right eyes through out the experimental duration as model control group.The guinea pigs were sacrificed and the posterior sclera tissue of the eyeballs were collected at 2,7 and 14 days after injection of drug.The expressions of collagen typeⅠmRNA and fibronectin mRNA were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR).This study followed the Regulation for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission.Results The expression level of collagen type Ⅰ mRNA in the posterior sclera of guinea pig was lower but that of fibronectin mRNA was higher in TIMP-2 group than self-control group,showing significant differences between them (P＜0.05).The expression level of collagen type Ⅰ mRNA in the posterior scleral tissue began to increase from the 2nd day after drug injection and was obviously elevated at the 7th day and then gradually decreased at the 14th day.However,the expression level of fibronectin mRNA in the posterior scleral tissue showed the opposite pattern.The expression levels of collagen typeⅠmRNA and fibronectin mRNA at the 7th after drug injection were significantly lower than that at the 2nd day or 14th day (P＜0.01).Conclusion Suprachoroidal injection of TIMP-2 in form-deprivation myopia could up-regulate the expression of collagen typeⅠmRNA and down-regulate the expression of fibronectin mRNA in the posterior scleral tissue.It may slow down the sclera remodeling of form-deprivation myopia in guinea pig in the early stage.

OBJECTIVELong time exhaled oxygen will induced oxygen toxicity. Some studies had found that different pathology may exised in normobaric and hyperbaric pulmonary oxygen toxicity, and nitric oxide synthase (NOS) may play a role. In this study, we discussed the change of NOS in normobaric and hyperbaric pulmonary oxygen toxicity.

METHODSSixty male SD rats were randomly divided into 6 groups (n = 10), exposed to 1 ATA (atmosphere absolute), 1.5 ATA, 2 ATA, 2.5 ATA and 3 ATA, 100% oxygen for 56, 20, 10, 8, 6 hours respectively. Rats were exposed to air as control. After exposure, the protein in bronchoalveolar lavage fluid (BALF), the wet/dry weight of lung and the expression of eNOS, nNOS in lung were defined.

RESULTSAs compared to air group, the protein in BALF, the wet/dry of lung were significantly elevated in 1.0 ATA group, while these changes were not so obviously in the other groups, and these changes in hyperbaric oxygen group (approximately 1.0 ATA) were significantly decreased as compared with nonnrmobaric oxygen group (1.0 ATA). The expression of nNOS were not changed in normobaric and hyperbaric pulmonary oxygen toxicity, while the expression of eNOS was significantly decreased in 2 ATA group, and significantly elevated in 2.5 ATA and 3 ATA group.

CONCLUSIONThe expression of eNOS can change when exposed to different pressures of oxygen.

Animals ; Disease Models, Animal ; Lung ; metabolism ; Male ; Nitric Oxide Synthase Type I ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Oxygen ; poisoning ; Pressure ; Rats ; Rats, Sprague-Dawley

In the etiology study of epidemiology, selection bias will lead to the fact that the research sample cannot represent the general population, the association between exposure and outcome among those selected for analysis differs from the association among those eligible, and the true causal association cannot be inferred. Directed acyclic graphs (DAGs) could visualize complex causality, introduce the Collider-stratification bias using simple graphics language, provide a simple and intuitive way to identify Selection bias, different types of selection bias are verified by the graphic structure of the Collider-stratification bias. In practical studies, there may be multiple biases at the same time, improper adjustment of the collider will lead to Collider-stratification bias, open a backdoor path, even change the size and direction of the confounding bias. In order to obtain an unbiased estimate of the exposure to the outcome, it is necessary to identify the collider and avoid the adjustment to prevent the occurrence of Collider-stratification bias by using DAGs.

Objective To examine the association between tea drinking and the risk of lung cancer in Chinese population.Methods All relevant published articles in Chinese and English literature database were identified.Meta-analysis was conducted.Combined odds ratio (OR) and 95％ confidence interval (CI) were calculated to estimate the associations and dose-response relationship between tea drinking and the risk of lung cancer.Results Twelve studies were included.An inverse association with lung cancer was observed on tea drinkers when compared to non-tea drinkers (OR=0.66,95％CI:0.49-0.89).Conclusion Tea drinking might serve as a protective factor on lung cancer in the Chinese population.

Abdominal Wall ; Adenocarcinoma ; diagnosis ; Colonic Neoplasms ; diagnosis ; Female ; Histiocytoma, Malignant Fibrous ; diagnosis ; Humans ; Ileal Neoplasms ; diagnosis ; Ileocecal Valve ; Leiomyoma ; diagnosis ; Middle Aged ; Neoplasms, Multiple Primary ; diagnosis ; Soft Tissue Neoplasms ; diagnosis ; Uterine Neoplasms ; diagnosis

OBJECTIVE: To improve DNA extraction from bloodstain on the filter paper and to establish a rapid, simple, and cost-effective method for DNA extraction suitable for database construction. METHODS: Seven hundred and fifty two aged bloodstains on filter paper were randomly divided into four groups. The four different DNA extraction methods were compared with each other, and two DNA extraction methods used for 63 fresh bloodstains on filter paper were also compared with each other. RESULTS: There were no statistically significant differences observed among the four DNA extraction methods (P > 0.05) for aged bloodstains on filter paper; But the difference between the two DNA extraction methods for fresh bloodstains on filter paper was obviously (P < 0.05). CONCLUSION Extraction of DNA samples from aged bloodstains on filter paper can be accomplished by using Chlex-100 methodology directly with no need to wash the bloodstains.
Blood Stains ; Chelating Agents ; DNA/isolation & purification* ; Endopeptidase K ; Forensic Medicine/methods* ; Humans ; Indicators and Reagents/chemistry* ; Polymerase Chain Reaction ; Resins, Synthetic ; Specimen Handling/methods* ; Water

Objective By sequenceing the Cj1136,Cj1138 and Cj1139 gene of Campylobacter jejuni(C. Jejuni) strains associated with Guillain-Barre Syndrome(GBS),features of Cj1136,Cj1138 and Cj1139 gene were studied.Results were compared with the C.jejuni strain NCTC11168, to find the mutations in sequence of C.jejuni which inducing GBS and their polygenetic relationship was analyzed.Methotis Three GBS-associated C.jejuni strains were isolated from stools of GBS patients from Hebei province who had been diagnosed as clinical AMAN pattern and electrophysiological tests were performed.After distilling and sequencing Cj1136,Cj1138 and Cj1139 genes,results were spliced and assembled into a complete sequence by the terminals overlapped with each other.Sequences of Cj1136,Cj1138 and Cj1139 genes were compared with NCTC11168,to find the mutations and gene feature.Results The Cj1136,Cj1138 and Cj1139 gene of the three GBS-associated C.jejuni strains were composed by 1173 base pairs,1170 base pairs,912 base pairs respectively. The alignment with the related sequence of NCTC11168 showed that there were two same mutations in the Cj1138 gene of the three C.jejuni stains.Data from phylogenetic analysis demonstrated that the three C.jejuni strains were genetically closed to NCTC11168,with the biggest phylogenetic distance between the three of them as 2.1%.Conclusion When compared with NCTC11168 the Cj1138 gene of the three GBS-associated C.jejuni strains had the same mutations which might be related to the development of GBS.Relation between the variation and GBS-pathogenesis remained to be confirmed.The mutations found in the three C.jejuni strains established the foundation for exploring the biological characteristics of GBS-associated C.jejuni strains and demonstrated that the GBS-associated C.jejuni strains of Hebei province having its regional features.

OBJECTIVETo apply pulse-field gel electrophoresis analysis(PFGE) in analysing a case of food poisoning caused by Vibrio parahaemolyticus.

METHODSPFGE using restriction enzyme Not I was employed in molecular subtyping of thirty strains of V. parahaemolyticus isolated from a case of food poisoning in Guangzhou city and PFGE patterns were analyzed by using BioNumerics Version 4.0 software to perform cluster analysis. Pattern profiles were compared by using the Dice coefficient and unweighted pair group method with arithmetic averages (UPGMA).

RESULTSThirty strains were of the same type of pulsotype.

CONCLUSIONSMolecular subtyping by PFGE might disclose the epidemiological relationships of the strains from humans, food and the environment, giving a strong molecular epidemiological evidence and a support for the source-tracking of outbreak events.

Bacterial Typing Techniques ; methods ; China ; Electrophoresis, Gel, Pulsed-Field ; methods ; Foodborne Diseases ; microbiology ; Humans ; Vibrio parahaemolyticus ; classification ; genetics ; isolation & purification

BACKGROUNDCardiac troponin-I (cTnI) is one of the three regulatory subunits of the cardiac troponin which has the high sensibility and specificity of responding to myocardial injury. Studies have demonstrated that cTnI is released into the blood stream within hours following acute myocardial reperfusion injury. The clinical utility of cTnI for the assessment of myocardial damage is that it is more specific than creatine kinase MB (CKMB). This study investigated cTnI as a sensitive marker of myocardial reperfusion injury and its clinical value on beating heart surgery with right sub-axiliary incision.

METHODSFrom December 2002 through December 2004, 100 patients with atrial septal defect (ASD), ventricular septal defect (VSD), atrial septal defect and ventricular septal defect (ASD + VSD), and tetralogy of Fallot were randomly divided into two groups: the treatment group (n = 50) was operated on with a beating heart under extracorporeal circulation (ECC), and the control group (n = 50) on an conventional arresting heart under ECC. The two groups both used a right sub-axillary incision. Blood samples from a central venous catheter (CVC) were collected before, at the end of aortic clamping, immediately after discontinue cardiopulmonary bypass (CPB), 3, 6, 24, and 48 hours after operation. The Abbott Axsym system with hol-automation fluorescent immunity analyzer was used for the quantitative determination of cTnI. cTnI was detected to investigate the effect of myocardial ischemia reperfusion injury and the clinical value of beating heart surgery with right sub-axillary incision.

RESULTSThere were no significant differences between the two groups before operation. At the end of aortic clamping and thereafter, cTnI significantly increased in both groups, and reached the peak point at 6 hours after operation. At all the tested points, cTnI was significantly higher in the control group than the beating heart group (P < 0.05), especially at 6 hours post operation (P < 0.01). The operating time and ECC duration were shortened and the dosage of dopamine was decreased, when compared with the control group.

CONCLUSIONSThere was less cTnI measured in the beating heart group than in the control group after CPB, demonstrating that beating heart surgery may significantly reduce myocardial reperfusion injury.

Adolescent ; Adult ; Child ; Child, Preschool ; Coronary Artery Bypass, Off-Pump ; methods ; Creatine Kinase, MB Form ; blood ; Fatty Acid Binding Protein 3 ; Fatty Acid-Binding Proteins ; blood ; Female ; Heart Defects, Congenital ; blood ; surgery ; Heart Valve Diseases ; blood ; surgery ; Humans ; Male ; Troponin I ; blood ; Young Adult

OBJECTIVETo investigate the incidence of complications of canalith repositioning procedure (CRP) for benign paroxysmal positional vertigo (BPPV) in order to recognize and intervene the complication.

METHODSTotally 430 cases of BPPV were treated by CRP between Jan., 2005 and Nov., 2007. The patients with complication were retreated with CRP according to the new canals otolith falling into.

RESULTSThere were 313 patients with posterior canal BPPV, among which 5 had complications during CRP for posterior canal BPPV and 3 for horizontal canal BPPV. And 1 patient transformed from cupulolithiasis to canalithiasis during Semont CRP, which made CRP possible. Three patients had horizontal BPPV during CRP for posterior canal BPPV. Horizontal BPPV emerged during CRP for anterior canal BPPV in 1 patient. CRP for the posterior BPPV had more patients with complication than that of CRP for the anterior BPPV, but the percentage was on the contrary, and they were 1.9% (8/313) and 28.6% (2/7) respectively. The rate of complication during CRP was 3.3% (14/430) and all of them recovered well with CRP.

CONCLUSIONSThere are possibility for canal otolith transferred from one canal to another. Careful observation of nystagmus and reevaluation of the patients with BPPV in case of unsuccessful treatments are crucial to determine the complications.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Male ; Middle Aged ; Otolithic Membrane ; Semicircular Canals ; Vertigo ; diagnosis ; therapy ; Young Adult