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

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.

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.

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 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.

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.

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 analyzed the characteristics of migrainous vertigo (MV), a kind of paroxysmal vertigo, in order to demonstrate the extent of damage and dysfunction in MV and to judge whether MV is peripheral or central vertigo.

METHODSTwenty-two cases of acute (5 cases) or subacute (17 cases) MV were examined with oto-neurological tests, spontaneous nystagmus, positional nystagmus and auditory tests.

RESULTSThere were 6 males and 16 females. Among those patients, 15 had migraine, 17 motion sickness, 15 family history of migraine or motion sickness, 1 visual aura, 7 motion intolerance (vertigo from head movement and body movement), 4 photophobia, 6 phonophobia and 5 vertigo from insomnia and emotion. There were likely to have vertigo in menstrual period in 2 cases. The duration of vertigo lasted from minutes to days. For pure-tone audiometric, 9 were normal which from mild to moderate hearing loss. Three cases had abnormal high frequency ABR bilaterally and 10 abnormal unilaterally. Subjective visual vertical were normal in all of the cases. Vestibular evoked myogenic potentials were abnormal in 14 cases (13 had low amplitude and 1 had longer latency of P13 wave). Bithermal caloric test was abnormal in 3 cases and 11 had abnormal ocular movement (9 with low gain of optokinetic nystagmus, 1 with overshoot in saccade and 1 with vertical nystagmus after head shaking), in which 10 had abnormal high frequency ABR and 1 was normal.

CONCLUSIONSMV could be peripheral or central vertigo and MV should be included in the differentiation of peripheral and central vertigo.

Adolescent ; Adult ; Child ; Electronystagmography ; Evoked Potentials, Auditory, Brain Stem ; Female ; Humans ; Male ; Middle Aged ; Migraine Disorders ; complications ; physiopathology ; Vertigo ; etiology ; physiopathology ; Young Adult

OBJECTIVEThe acute toxic effects of Aristolochia manshuriensis (GMT) and the total aristolochic acids (TA) were compared in mice with aristolochic acid A (AA) as the dose standard. The dose relationship of the renal toxicity induced by Aristolochia manshuriensis was determined.

METHODA single dose of GMT extract or TA was given intragastrically to mice at different doses. LD50 values, the blood levels of BUN, Cr and ALT were measured. A histomorphological study was also performed in livers and kidneys of mice.

RESULTLD50 value of GMT extract was 4.4 g x kg(-1) which was equivalent to 40 mg x kg(-1) as calculated by the content of AA in GMT extract, and this value was comparable with LD50 obtained from TA given intragastrically in mice (equivalent to 33 mg x kg(-1) of AA for male and 37 mg x kg(-1) for female). GMT extract caused a significant increase in blood BUN and Cr and an obvious morphological change in kidney in a dose-dependent manner at doses of AA 4.5 mg x kg(-1) and above. Liver damage, characterized by both an increase in blood level of AST and histomorphological change, was observed at doses of AA 25 mg x kg(-1) and above. All changes were in proportion to the doses of AA.

CONCLUSIONGMT causes both renal and liver toxicity. The dose leading to nephrotoxicity is much lower than that inducing hepatatoxicity. Aristolochic acids existed in GMT are the main toxic components to cause renal toxicity which is a crucial cause to result in death. The lethality and nephrotoxicity of GMT is in proportion to the doses of AA.

Alanine Transaminase ; blood ; Animals ; Aristolochia ; chemistry ; Aristolochic Acids ; administration & dosage ; isolation & purification ; toxicity ; Aspartate Aminotransferases ; blood ; Blood Urea Nitrogen ; Creatinine ; blood ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; toxicity ; Female ; Kidney ; pathology ; Lethal Dose 50 ; Liver ; pathology ; Male ; Mice ; Mice, Inbred ICR ; Random Allocation