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Biomedical subjects

Wei Gao

Publications and source records attributed to Wei Gao.

At least 73 records · Page 4Linked to original sources
PubMed2005

[Recombinant adeno-associated viral vector 2-mediated gene transfer of VEGF165 improved porcine chronic myocardial ischemia].

OBJECTIVE: Vectors commonly used for therapeutic angiogenesis such as adenovirus and plasmid had their own limitations. Adenovirus-associated virus (AAV) is a relatively new but probably more ideal vector as it is safe and efficient. We will study the efficiency of recombinant AAV-2 mediated vascular endothelial growth factor165 gene transfer in inducing angiogenesis and arteriogenesis, in improving blood flow and myocardium function in a porcine chronic myocardial ischemic model. METHODS: Chinese experimental minipigs underwent placement of a left circumflex artery aneroid constrictor. Five weeks later, electrocardiogram, coronary angiography and magnetic resonance imaging were performed to confirm occlusion of LCX or ischemia of myocardium in LCX territory. Coronary blood flow, myocardium perfusion and left ventricular wall function were also evaluated. Then the animals were randomized to treatment with rAAV2-VEGF(165) (1 x 10(12) virus genome) or administration of PBS, both by direct myocardial injection. Three and six months after therapy, the animals were evaluated with regard to expression of VEGF(165) Capillary density and arteriole density of the ischemic myocardium, coronary angiography, myocardial perfusion and left ventricular function were also assessed six months after therapy. RESULTS: Five weeks after aneroid occluder implantation, all the animals demonstrated complete or nearly complete occlusion of LCX and perfusion deficiency in LCX territory. Three months after therapy, expression of VEGF(165) mRNA and protein were higher in the VEGF than control group. The difference between the two groups diminished after six months. There was significant increase in capillary density (1404.06 +/- 250.48/mm(2) vs 976.88 +/- 344.79/mm(2), P < 0.05) and arteriole density (167.81 +/- 36.29/mm(2) vs 116.56 +/- 34.48/mm(2), P < 0.05) in VEGF group compared with control. Comparison of myocardial perfusion demonstrated marked differences between the two groups with significant improvement in animals treated with rAAV2-VEGF(165). No significant improvement in left ventricular function was seen in either the VEGF or control group. CONCLUSIONS: Transmyocardial delivery of rAAV2-VEGF(165) resulted in VEGF gene expression for at least three months and stimulated angiogenesis and arteriogenesis in porcine model of chronic myocardial ischemia. Myocardial perfusion was also improved after VEGF gene delivery.

Adenoviridae↗
PubMed2005

[Molecular epidemiology of penicillin-nonsusceptible Streptococcus pneumoniae in Beijing, China, 2000-2002].

OBJECTIVE: To investigate the molecular epidemiology of the penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) in Beijing, China. METHODS: The resistant profile of 63 PNSP strains isolated from children with upper respiratory infection in the outpatient department from 2000 to 2002 was analyzed. The isolates were compared by detecting restriction fragment length polymorphism (RFLP) of the penicillin-binding protein (PBP) genes pbp1a, pbp2b and pbp2x and by applying chromosomal macrorestriction patterns detected by pulsed-field gel electrophoresis (PFGE). RESULTS: Sixty-one (96.8%) out of the 63 PNSP strains were multidrug-resistant Streptococcus pneumoniae (Sp). Overall, 16 resistance profiles were found, 14 of which were multidrug resistant profiles. Seven (33.3%), 6 (24.0%) and 8 (47.1%) strains resistant to one of cephalosporins were respectively isolated in 2000, 2001 and 2002, indicating an increasing trend but without any statistical significance (chi(2) = 2.42, P > 0.05). The RFLP results showed 8, 9 and 18 genotypes of pbp1a, pbp2b and pbp2x, respectively. A total of 30 patterns were found according to the three pbps types. And clearly, the most common 5 patterns had main resistant profiles. In the mean time, 35 different PFGE types were elucidated and the 9 PFGE types, with each consisting of more than 2 strains, covered 59% (37/63) of all isolates. One of the 9 PFGE type included 2 strains, both possibly related to each other, but one of them was detected to be the same PFGE pattern with clones prevalent in Asia, Vietnam-19 serogroup, Singapore-19 serogroup, Taiwan-19 serogroup, and the other was the same as that in Korea-19 serogroup. CONCLUSION: Multidrug resistance is very common among PNSP isolates in Beijing. The spread of a few multidrug resistant clones is an important factor for the prevalence of PNSP. It deserves the concern that the resistant clones spread in Asia have been found in Beijing.

Child, Preschool↗
PubMed2005

[Genotyping of ampicillin-resistant Haemophilus influenzae].

OBJECTIVE: Haemophilus (H.) influenzae is a gram-negative bacillus that is a common commensal organism of the human upper respiratory tract and an important cause of human diseases such as pneumonia, meningitis, septicemia, epiglottitis and cellulitis. Strains of H. influenzae are classified according to their capsular polysaccharide. There are six serotypes, designated as a through f. In addition, there are nonencapsulated strains. Although the type of infectious diseases caused by H. influenzae has changed considerably in recent years because of the widespread and routine immunization of children against type b H. influenzae (Hib), Hib remains an important pathogen. Ampicillin is the drug of choice for treating many infections caused by H. influenzae, but its usefulness has been compromised by the increasing prevalence of ampicillin-resistant strains. The continued monitoring of resistant strains by using genotyping methods may provide insights into the epidemiology of transmission. A molecular epidemiological study of ampicillin-resistant H. influenzae derived from nasopharyngeal swabs specimens of children less than 5 years of age with respiratory tract infection were investigated in this study. METHODS: A total of 899 isolates were collected from Beijing, Shanghai, and Guangzhou during 2000-2003. Susceptibility to ampicillin was determined by using E-test. Ampicillin-resistant H. influenzae strains were selected according to National Committee for Clinical Laboratory Standards (NCCLS) 2002 breakpoints. Nested PCR method with primers specific for bexA gene and b capsulate type-specific gene was established. Genotyping by pulsed-field gel electrophoresis (PFGE) and multiplex PCR assay was performed for all ampicillin-resistant H. influenzae strains. RESULTS: Seventy-four ampicillin-resistant H. influenzae strains were obtained. Two strains were positive by nested PCR, characterized as b genotype. The incidence of Hib in ampicillin-resistant H. influenzae strains was 2.7%; 38 genotypes were detected by PFGE. Detection of five types strains of clonal dissemination by PFGE accounted for 55.4% in all ampicillin-resistant H. influenzae strains. Among them eighteen H. influenzae strains belonged to one type, accounted for 24.3% in all ampicillin-resistant H. influenzae strains. Thirty one genotypes were identified by multiplex PCR assay for ampicillin-resistant H. influenzae. The identity ratio of PFGE and multiplex PCR was 63.5%. CONCLUSION: In Beijing, Shanghai and Guangzhou areas 55.4% of ampicillin-resistant H. influenzae strains had clonal dissemination during the 4 years.

Ampicillin Resistance↗
PubMed2005

[Risk factors for arrhythmia early after transcatheter closure of perimembranous ventricular septal defects].

OBJECTIVE: Perimembranous ventricular septal defects (PMVSDs) is the most common type of congenital ventricular septal defects (VSD), which accounts for 70% approximately 80% of VSD. The structure of PMVSDs is very complex, it is close to tricuspid valve, mitral valve and aortic valve. The atrioventricular (AV) node is located in the posterior upper membranous ventricular septum and branches into left and right bundle in the posterior lower margin. This increases the risk of transcatheter closure of PMVSDs. Arrhythmias is the common complication after transcatheter closure of PMVSDs. The present study aimed to identify the risk factors resulting in arrhythmias after transcatheter closure of PMVSDs in patients under 18 years of age to decrease the incidence of arrhythmias after the interventional catheterization. METHODS: A retrospective analysis was performed on the patients treated with transcatheter intervention from June 2002 to June 2004. Transcatheter closure of PMVSDs with Amplatzer membranous septal occluder and a domestic product was performed in 89 cases after obtaining consent themselves and/or their guardian or parents, 47 cases were males and 42 females. The age of the cases ranged from 3 to 18 years (mean 8.2 years) and the body weight ranged from 13 to 55 kg (mean 26.7 kg). They were all diagnosed as having PMVSDs with trans-thoracic echocardiography (TTE) before the interventional catheterization, the electrocardiographic (ECG) and chest X-ray (CXR) findings were recorded. A simultaneous care ECG and TTE were performed during operation in order to identify the effect of the transcatheter closure, the heart structure and functional changes and whether or not arrhythmias occurred, respectively. In 80 cases AGA Amplatzer membranous septal occluder was used and in 9 cases a domestic product was used. Follow-up was performed based on the echocardiography and ECG. RESULTS: The devices were successfully implanted in 89 cases; 11 cases (12%) developed various block of heart conduction within 5 days, which included first degree AV block in 1 patient, third degree AV block in 1, left anterior bundle branch block in 5, partial right bundle branch block in 4, complete right bundle branch block in 3, and 3 patients had two kinds of heart block. Eight patients were treated with corticosteroids, 6 of them recovered within 14 days, 1 patient within 1 month and in 1 case the problem shifted from first degree block and left anterior bundle branch block to left anterior bundle branch block 5 days later and that persisted for 6 months. It was found that the distance from upper margin of defects to the aortic valve < 3 mm, the diameter of ventricular septal defect > or = 8 mm, the diameter of device > or = 10 mm, blood pH < 7.35 and arteriovenous track building time after the success of the Seldinger technique > or = 60 min were independent predictors of post-closure arrhythmias. CONCLUSION: Arrhythmias remain the severe early complications after interventional catheterization for PMVSDs in patients under 18 years of age. Shortening of operation time, prevention of acidosis and strict selection of indications may be the most effective measures to prevent arrhythmias after transcatheter closure of PMVSDs in patients under 18 years of age.

Adolescent↗
PubMed2005

[Protective effect of the pretreatment with Chuanxiong-phthalide A on the vascular endothelial cells impaired by the ischemia and reperfusion in isolated rats hearts].

OBJECTIVE: The aim of this study was to investigate the protective effect of Chuanxiong-pathalide A on the injury of endothelial cell induced by ischemia and reperfusion in isolated rat hearts. METHOD: The isolated rat hearts were perfused under constant pressure with Chuanxiong-pathalide A at the concentrations of 0.012 5 mg x mL(-1), 0.025 mg x mL(-1) and 0.05 mg x mL(-1) within 10 min followed by a 10-min washout period before the induction of a 30-min normothermic global ischemia and 60 min reperfusion. RESULT: Pretreatment with Chuanxiong-pathalide A produced a reduction in the incidence of reperfusion-induced ventricular fibrillation (VF) and ventricular tachycardia (VT). Pretreatment of the hearts with high dose of Chuanxiong-pathalide A (0.05 mg x mL(-1)) prior to the ischemia and reperfusion, reduced the incidence of reperfusion-induced VF and VT to 37.5% as compared with non-pretreated control group (P < 0.05). The duration of occurrence of VF and VT in the group pretreated with Chuanxiong-pathalide A at dosages of 0.012 5 mg x mL(-1), 0.025 mg x mL(-1) and 0.05 mg x mL(-1) were (7.50 +/- 1.61), (1.64 +/- 0.67) and (1.06 +/- 0.70) min respectively, which were significantly shorter than (23.51 +/- 3.99) min in non-pretreated control group; 0.05 mg x mL(-1) of Chuanxiong-pathalide A increased coronary flow in comparison with the control group. The content of SOD in the group pretreated with 0.05 mg x mL(-1) of Chuanxiong-pathalide A was (59.6 +/- 18.7) U x mg(-1), significant lower than (92.3 +/- 19.0) U x mg(-1) in the non-pretreated group. The contents of LDH and MDA were (2 378.0 +/- 196.3) U x g(-1) and (12.1 +/- 1.3) nmol x mg(-1) in the non-pretreated group, which were much higher than the values of (1 669.4 +/- 192.5) U x g(-1) and (6.9 +/- 0.8) nmol x mg(-1) in the group pretreated with Chuanxiong-pathalide A respectively. In addition, enzymeimmunoassays showed an decreased production of IL-1beta and the ratio of TXB2/6-Keto-PGF1alpha. CONCLUSION: Our results show that chuanxiong-pathalide A pretreatment can protect the endothelial function from the injury caused by ischemia and reperfusion.

Animals↗
PubMed2005

[Study on Haemophilus influenzae type b: data from autopsy of community acquired pneumonia among children].

OBJECTIVE: To evaluate the status of Haemophilus influenza type b(Hib) on death cases of children from community-acquired pneumonia (CAP) and to estimate the value of direct in-situ polymerase chain reaction (ISPCR) on diagnosis of children CAP, pathogenically. METHODS: Ordinary PCR, Southern blot and direct ISPCR were applied and compared in detecting Hib in 100 paraffin-embedded lung tissues of autopsy children died of CAP. RESULTS: No major difference on the detection rate of Hib between 50-60s and 80s-2002 was found. The detection rate of Hib by direct ISPCR was higher than the other two methods. By Southern blot, Hib was identified from 8 out of 100 samples (8%), including 4 out of 56 in 1950-60s (7.1%) and 4 out of 44 (9.1%) (chi2 = 0.084, P>0.05) in 1980s-2002. By ISPCR, Hib was identified from 17 out of 100 samples (17%), including 8 out of 56 in 1950-60s (14.3%) and 9 out of 44 (20.5%) with chi2 = 0.665, P > 0.05, in 1980s-2002. Positive cases diagnosed by both Southern blot and ISPCR were 7%. CONCLUSION: Hib was one of the main bacterial pathogens causing CAP and deaths among children. Direct ISPCR was prefertable to be used in pathogenic diagnosis on children pneumonia, in terms of its sensitivity, specificity and localization.

Age Factors↗
PubMed2005

Changes of Cu, Zn, and Cd speciation in sewage sludge during connposting.

The potential toxicity risks from heavy metals depend on their chemical speciation. The four stages of the Tessier sequential extraction method were employed to investigate changes in heavy metal speciation (Cu, Zn, and Cd) of sewage sludge during forced aeration composting, and then to identify whether the composting process would reduce or enhance their toxicities. Throughout the composting process, the exchangeable, carbonate-bound, Fe-Mn oxide-bound, and organic matter-bound fractions of Cu were converted to the residual Cu fraction. The organic matter-bound Cu fraction greatly contributed to this transformation. Residual Zn fraction was transformed to the Fe-Mn oxide-bound and organic matter-bound fractions after composting. The residual Zn fraction was a major contributor to the organic matter-bound Zn fraction. The availability of Cu and Zn was reduced by composting such that the risk of heavy metal toxicity decreased with prolonged treatment times. Additionally, attention should be paid to the increased availability of Cd in sewage sludge after composting treatment.

Hydrogen-Ion Concentration↗
PubMed2004

Herpes zoster in women with and at risk for HIV: data from the Women's Interagency HIV Study.

BACKGROUND: Herpes zoster occurs at all CD4 cell counts in HIV-infected adults. It was hypothesized that even in the era of highly active antiretroviral therapy (HAART), zoster risk is higher in HIV-infected than uninfected women. METHODS: Generalized estimating equations modeled self-reported occurrence of zoster between semiannual visits among 1832 HIV-infected and 489 HIV-uninfected women in the Women's Interagency HIV Study followed for up to 7.5 years. RESULTS: A total of 337 (18.4%) HIV-infected and 7 (1.4%) HIV-uninfected women reported zoster at some time during follow-up. Using HIV-infected women with CD4 >750 cells/microL as the reference category, the odds ratios for reporting zoster since the prior visit were: 1.43 (95% CI 0.86-2.37) for CD4 500-749 cells/microL, 2.07 (95% CI 1.27-3.38) for CD4 350-499 cells/microL, 2.72 (95% CI 1.66-4.46) for CD4 200-349 cells/microL, and 3.16 (95% CI 1.92-5.18) for CD4 <200 cells/microL, compared with 0.11 (95% CI 0.046-0.26) for HIV-uninfected women. In multivariate analyses using visits from all HIV-infected women and only those who initiated HAART, lower CD4 cell count was more strongly associated with zoster incidence than were other clinical indicators. CONCLUSIONS: Herpes zoster is associated with degree of immunosuppression in HIV-infected women, but even women with high CD4 counts are at greater risk of zoster than HIV-uninfected women.

Adult↗
PubMed2004

Tissue inhibitor of metalloproteinases-4 suppresses vascular smooth muscle cell migration and induces cell apoptosis.

In a previous study, we have demonstrated that overexpression of the tissue inhibitors of metalloproteinases-4 (TIMP-4) can inhibit the neointima formation in the rat carotid model. To define the functions of tissue inhibitor of metalloproteinases-4 (TIMP-4) in SMCs, we transduced human TIMP-4 cDNA into rat aortic SMCs by using adenoviral vector. Overexpression of TIMP-4 blocked the conversion of pro-MMP-2 to the active form and inhibited basic fibroblast growth factor-induced migration by 56.7% (p < 0.01). Overexpression of TIMP-4 markedly increased apoptotic cell death without changing their proliferation. Importantly, overexpression of human TIMP-4 in the wall of balloon-injured rat carotid artery also increased SMC apoptosis. The percentages of TUNEL-positive cells of total cells increased significantly in AdTIMP-4 infected group compared with AdGFP infected group. These findings demonstrate that TIMP-4 can inhibit SMCs migration and induce apoptosis in vitro and in vivo, which may generate new targets for prevention and treatment of vascular diseases.

Angioplasty, Balloon↗
PubMed2004

Association between renal disease and outcomes among HIV-infected women receiving or not receiving antiretroviral therapy.

BACKGROUND: The associations of proteinuria and an elevated creatinine level with progression to acquired immunodeficiency syndrome (AIDS) and death in the era of highly antiretroviral therapy (HAART) have not been fully described. METHODS: This analysis includes 2038 human immunodeficiency virus (HIV)-infected women from the Women's Interagency HIV Study. Time to the development of a new AIDS-defining illness (ADI) and death was modeled using proportional hazards regression before the widespread availability of HAART and after initiation of HAART. RESULTS: Of the 2038 subjects, the 14.1% of women with proteinuria had lower CD4 lymphocyte counts and higher viral loads (P<.0001 for all) at baseline and before initiation of HAART. Before the widespread availability of HAART, proteinuria was associated with an increased risk for development of ADI (hazard ratio [HR], 1.37; P=.005), and proteinuria and an elevated creatinine level were both associated with an increased risk of death (for proteinuria: HR, 1.35 [P=.04]; for creatinine: HR, 1.72 per decrease in the inverse unit [P=.02]). Among women initiating HAART, an elevated creatinine level remained associated with an increased risk of development of ADI (HR, 1.54 per decrease in the inverse unit; P=.03), and proteinuria and an elevated creatinine level were associated with an increased risk of death (for proteinuria: HR, 2.07 [P=.005]; for creatinine: HR, 1.96 per decrease in the inverse unit [P=.04]). CONCLUSIONS: Proteinuria and an elevated creatinine level were associated with an increased risk of death and development of ADI. These associations may reflect the direct role of the kidney in modulating HIV disease, or they may act as markers of greater comorbidity.

Adult↗
PubMed2004

Association between female breast cancer and cutaneous melanoma.

Epidemiologic studies have provided suggestive evidence of a link between cutaneous melanoma (CM) and breast cancer (BC). Moreover, carriers of mutations in the breast cancer predisposition gene, BRCA2, have an increased risk of melanoma while carriers of mutations in the melanoma susceptibility gene, CDKN2A, exhibit a higher than expected risk of breast cancer. These findings raise the possibility that pathways involved in the development of CM and BC overlap and that survivors of one cancer may be prone to develop the other. To this end, we set out to determine if survivors of female BC in the Surveillance, Epidemiology and End Result (SEER) database are at increased risk for CM and vice versa. We followed female BC patients registered in the 1973-1999 SEER database for development of a second CM and female CM patients for the development of a second BC. The expected number of cases was then compared to the observed number of cases using standardized incidence ratios. Overall, we found a modest but statistically significant increased risk of CM among female BC survivors and vice versa. Among young BC patients, we observed a 46% elevated risk of a second CM. Women who underwent radiation therapy exhibited a 42% increased risk for CM. The risks of BC among female CM survivors and CM among BC survivors were also elevated, albeit to a much lesser degree (overall, 11% and 16%, respectively). We found a mutual association between female BC and CM. The elevated risk for CM, especially among younger BC patients, suggests that the genetic observations from high-risk groups may also be operative at a much lower level in the general BC population.

Adult↗
PubMed2004

Supramolecular assemblies of a naturally derived sophorolipid.

Acidic sophorolipid (SL) molecules derived from yeasts represent a novel type of asymmetrical bolaamphiphiles due to their unique structural features that include an asymmetrical polar head size (disaccharide vs COOH), a kinked hydrophobic core (cis-9-octadecenoic chain), and a non-amide polar-nonpolar linkage. Light microscopy, small- and wide-angle X-ray scattering, FT-IR spectroscopy, and dynamic laser light scattering were used to investigate the supramolecular structures of the self-assembled aggregates of SL molecules at different pH values. In acidic conditions (pH < 5.5), giant twisted and helical ribbons of 5-11 microm width and several hundreds of micrometers length were observed for the first time. Increase in solution pH values slowed ribbon formation, decreased ribbon yield, and increased the helicity and entanglements of the giant ribbons. An interdigitated lamellar packing model of acidic SL-COOH molecules with a long period of 2.78 nm, stabilized by both the strong hydrophobic association between the cis-9-octadecenoic chains and strong disaccharide-disaccharide hydrogen bonding, is proposed. The neutralization of SL-COOH in water to SL-COONa produced clear solutions with the formation of short-range ordered aggregates. At concentrations below 1.0 mg/mL, the size of self-assembled aggregates increased as the concentration increased. At concentrations above 1.0 mg/mL, narrowly distributed micellar aggregates with a constant hydrodynamic radius (R(h)) of about 100 nm are formed. The large micelles show strong angular dependence with the fast mode appearing at scattering angle theta >/= 60 degrees.

Glycolipids↗
PubMed2004

[The protective effect of interleukin-1 receptor antagonist on postischemic reperfused myocardium and its possible mechanism].

OBJECTIVE: To observe the dynamic changes of plasma inflammatory cytokine interleukin-1 beta (IL-1 beta) in patients with acute myocardiac infarction (AMI) before and after recanalization of the infarct related artery (IRA) and to observe the effect of recombinant human IL-1 receptor antagonist (rhIL-1ra) on the postischemic reperfused myocardium in experimental rabbits. METHODS: (1) ELISA was used to measure the plasma IL-1 beta of 22 AMI patients, 20 males and 2 females, aged 64 +/- 12, before emergency percutaneous coronary intervention (PCI), and 12 hours and 24 hours after-intervention, and measure the plasma IL-1 beta of 8 healthy controls, 6 males and 2 females, aged 56 +/- 9. (2) Forty rabbits underwent ligation of the left circumflex branch of coronary artery (LCX) for 50 minutes and reperfusion for 4 hours after the ligatures were untied. The rabbits were randomly divided into 4 groups of 10 rabbits to be injected into the left ventricle immediately before the reperfusion with rhIL-1ra 10 mg/kg (group A), 20 mg/kg (group B), or 40 mg/kg (group C), and normal saline (control group) respectively. After reperfusion of 4 hours, the LCX was re-ligated. Evans blue was injected into the left ventricle. 15% KCl was injected intravenously to kill the rabbits. Their hearts were taken out to weigh the non-ischemic, ischemic, and necrotic cardiac muscles so as to calculate the infarct size. The myoperoxidase (MPO) activity was measured by colorimetry. Sections of myocardium were made. The number of apoptotic cardiomyocytes was evaluated by TUNEL method. The apoptotic rate of cardiomyocyte was measured by annexin V method. The DNA expression of myocardium was detected by DNA laddering method. The expressions of Bcl-2 and Bax apoptosis genes were assessed. RESULTS: (1) The average plasma IL-1 beta level of the 22 AMI patients before emergency PCI was significantly higher than that of the controls (28 pg/ml +/- 9 pg/ml vs. 20 pg/ml +/- 11 pg/ml, P < 0.05), and became the highest 12 hours after the intervention (86 pg/ml +/- 14 pg/ml), and the high level lasted to 24 hours after emergency PCI. (2) In the ischemia-reperfusion rabbit model, the infarct size was 47% +/- 7% in the group A, 34% +/- 8% in the group B, 31% +/- 6% in the group C, and 61% +/- 11% in the control group (P < 0.05, 0.01, and 0.01 respectively). The activity of myocardial MPO was 16.6 +/- 3.6 min(-1).g.w.w(-1) in the group A, 10.9 min(-1).g.w.w(-1) +/- 1.9 min(-1).g.w.w(-1) in the group B, 7.8 min(-1).g.w.w(-1) +/- 2.2 min(-1).g.w.w(-1) in the group C, and 20.5 min(-1).g.w.w(-1) +/- 4.5 min(-1).g.w.w(-1) in the control group (P < 0.05, 0.01, and 0.01 respectively). The cardiomyocyte apoptosis evaluated by TUNEL was 38.3 n/HP +/- 7.4 n/HP in the group A, 25.6 n/HP +/- 6.8 n/HP in the group B, 12.2 n/HP +/- 3.3 n/HP in the group C, and 44.4 n/HP +/- 9.5 n/HP in the control group (P < 0.05, and P < 0.01 respectively in comparison between the group B and the control group and between the group C and the control group). The apoptotic rate by annexin V method was 11.6% +/- 2.7% in the group A; 7.7% +/- 2.4% in the group B, 4.7% +/- 1.4% in the group C, and 15.6% +/- 3.5% in the control group (P < 0.05, 0.01, and 0.01 respectively). DNA electrophoresis showed scaling ladder pattern only in the control group. The fluorescent density of the apoptosis gene Bax in myocardium was 24.9 +/- 8.2 in the group A; 15.5 +/- 3.4 in the group B, 10.6 +/- 2.5 in the group C, and 33.3 +/- 9.4 in the control group (P = 0.0298, 0091, and 0052 respectively) and no significant difference in the expression of Bcl-2 was shown among the 4 groups. Myocardial MPO was correlated with cardiomyocyte apoptosis (r = 0.86 by TUNEL, P < 0.01; r = 0.75 by Annexin V method, P < 0.05). CONCLUSION: Inflammatory cytokine IL-1 beta is involved in myocardial ischemia-reperfusion injury. With potential therapeutic value in prevention and treatment of ischemia-reperfusion injury to myocardium, rhIL-1ra may reduce myocardial ischemia-reperfusion injury by suppression of cardiomyocytes apoptosis mediated by IL-als; 0.86 by TUNEL, P < 0.01; r = 0.75 by Annexin V method, P < 0.05). CONCLUSION: Inflammatory cytokine IL-1 beta is involved in myocardial ischemia-reperfusion injury. With potential therapeutic value in prevention and treatment of ischemia-reperfusion injury to myocardium, rhIL-1ra may reduce myocardial ischemia-reperfusion injury by suppression of cardiomyocytes apoptosis mediated by IL-1.

Acute Disease↗
PubMed2004

Biocompatibility of sorbitol-containing polyesters. Part I: Synthesis, surface analysis and cell response in vitro.

A series of sorbitol-containing polyesters were synthesized via a one-pot lipase-catalyzed condensation polymerization. Thin films were prepared by spin coating on silicon wafers and surfaces were analyzed by tapping mode atomic force microscopy and contact angle measurements. Surface morphologies and surface energies across the series of polyester films, including a poly(epsilon-caprolactone) (PCL) control were nearly indistinguishable. Biocompatibility of the sorbitol-containing polyester series was evaluated against a PCL control by measuring cell spreading and proliferation of a mouse fibroblast 3T3 cell line in vitro. Results confirmed that the sorbitol-containing polyester surfaces elicited cell behavior similar to the PCL control. These results establish the sorbitol-containing polyester series as a promising material for tissue engineering research and development.

3T3 Cells↗
PubMed2004

Leaf and canopy photosynthetic characteristics of cotton (Gossypium hirsutum) under elevated CO2 concentration and UV-B radiation.

Increases in both atmospheric CO2 concentration ([CO2]) and ultraviolet-B (UV-B) radiation on the Earth's surface are features of current climate change patterns. An experiment was conducted in sunlit, controlled environment chambers known as Soil-Plant-Atmosphere-Research (SPAR) units to determine interactive effects of elevated [CO2] and UV-B radiation on leaf and canopy photosynthetic characteristics of cotton. Six treatments were comprised of two CO2 levels of 360 (ambient) and 720 (elevated) microL L(-1) and three levels of 0 (control), 8, and 16 kJ m(-2) d(-1) biologically effective UV-B radiation. Treatments were imposed for 66 days from crop emergence through three weeks after the first flower stage. Plants grown in elevated [CO2] had significantly greater leaf area, higher leaf and canopy net photosynthetic rates (PN), lower dark respiration rate (Rd), and lower light compensation point (LCP) than plants grown in ambient [CO2]. There was no difference in CO2 compensation point (gamma), maximum rate of Rubisco activity (Vcmax), or light-saturated rate of electron transport (Jmax) between ambient and elevated CO2 treatments. When plants were grown in 8 kJ m(-2) d(-1) UV-B radiation, most of the measured photosynthetic parameters did not differ from control plants. High UV-B (16 kJ) radiation, however, caused 47-50% smaller leaf area, 38-44% lower leaf PN, 72-74% lower Vcmax, and 61-66% lower Jmax compared to the control. There were no interactive effects of [CO2] and UV-B radiation on most of the photosynthetic parameters measured. From the results, it is concluded that decreased canopy photosynthesis due to enhanced UV-B radiation in cotton is associated with both smaller leaf area and lower leaf PN, and loss of Rubisco activity and electron transport are two major factors in UV-B inhibition of leaf PN.

Carbon Dioxide↗
PubMed2004

Senescence and hyperspectral reflectance of cotton leaves exposed to ultraviolet-B radiation and carbon dioxide.

The objectives of this study were to determine the effects of UV-B radiation and atmospheric carbon dioxide concentrations ([CO(2)]) on leaf senescence of cotton by measuring leaf photosynthesis and chlorophyll content and to identify changes in leaf hyperspectral reflectance occurring due to senescence and UV-B radiation. Plants were grown in controlled-environment growth chambers at two [CO(2)] (360 and 720 micro mol mol(-1)) and three levels of UV-B radiation (0, 7.7 and 15.1 kJ m(-2) day(-1)). Photosynthesis, chlorophyll, carotenoids and phenolic compounds along with leaf hyperspectral reflectance were measured on three leaves aged 12, 21 and 30 days in each of the treatments. No interaction was detected between [CO(2)] and UV-B for any of the measured parameters. Significant interactions were observed between UV-B and leaf age for photosynthesis and stomatal conductance. Elevated [CO(2)] enhanced leaf photosynthesis by 32%. On exposure to 0, 7.7 and 15.1 kJ of UV-B, the photosynthetic rates of 30-day-old leaves compared with 12-day-old leaves were reduced by 52, 76 and 86%, respectively. Chlorophyll pigments were not affected by leaf age at UV-B radiation of 0 and 7.7 kJ, but UV-B of 15.1 kJ reduced the chlorophylls by 20, 60 and 80% in 12, 21 and 30-day-old leaves, respectively. The hyperspectral reflectance between 726 and 1142 nm showed interaction for UV-B radiation and leaf age. In cotton, leaf photosynthesis can be used as an indicator of leaf senescence, as it is more sensitive than photosynthetic pigments on exposure to UV-B radiation. This study revealed that, cotton leaves senesced early on exposure to UV-B radiation as indicated by leaf photosynthesis, and leaf hyperspectral reflectance can be used to detect changes caused by UV-B and leaf ageing.

Journal Article↗
PubMed2004

Interactive effects of ultraviolet-B radiation and temperature on cotton physiology, growth, development and hyperspectral reflectance.

Current conditions of 2-11 kJ m(-2) day(-1) of UV-B radiation and temperatures of >30 degrees C during flowering in cotton cultivated regions are projected to increase in the future. A controlled environment study was conducted in sunlit growth chambers to determine the effects of UV-B radiation and temperature on physiology, growth, development and leaf hyperspectral reflectance of cotton. Plants were grown in the growth chambers at three day/night temperatures (24/16 degrees C, 30/22 degrees C and 36/28 degrees C) and three levels of UV-B radiation (0, 7 and 14 kJ m(-2) day(-1)) at each temperature from emergence to 79 days under optimum nutrient and water conditions. Increases in main stem node number and the node of first fruiting branch and decrease in duration to first flower bud (square) and flower were recorded with increase in temperature. Main effects of temperature and UV-B radiation were significant for net photosynthetic rates, stomatal conductance, total chlorophyll and carotenoid concentrations of uppermost, fully expanded leaves during squaring and flowering. A significant interaction between temperature and UV-B radiation was detected for total biomass and its components. The UV-B radiation of 7 kJ m(-2) day(-1) reduced boll yield by 68% and 97% at 30/22 degrees C and 36/28 degrees C, respectively, compared with yield at 0 kJ m(-2) day(-1) and 30/22 degrees C. No bolls were produced in the three temperature treatments under 14 kJ m(-2) day(-1) UV-B radiation. The first-order interactions between temperature, UV-B radiation and leaf age were significant for leaf reflectance. This study suggests a growth- and process-related temperature dependence of sensitivity to UV-B radiation.

Carbon Dioxide↗