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W Gao

Publications and source records attributed to W Gao.

At least 55 records · Page 3Linked to original sources
PubMed2001

Importance of ICOS-B7RP-1 costimulation in acute and chronic allograft rejection.

Primary T cell activation requires B7-CD28 and CD40-CD154 costimulation, but effector T cell functions are considered to be largely independent of these costimulatory pathways. Although blockade of costimulation with cytolytic T lymphocyte-associated antigen 4-immunoglobulin (CTLA-4-Ig) or monoclonal antibody (mAb) to CD154 prolongs allograft survival, chronic rejection follows, which suggests that additional key costimulatory pathways are active in vivo. We found that both antibody to inducible costimulator (anti-ICOS) and an ICOS-Ig fusion protein suppressed intragraft T cell activation and cytokine expression and prolonged allograft survival in a manner similar to that in ICOS-/- allograft recipients. The combination of anti-ICOS therapy and cyclosporin A led to permanent engraftment. In addition, ICOS-B7RP-1 costimulation was required for the development of chronic rejection after CD40-CD154 blockade. These data demonstrate a key role for the ICOS-B7RP-1 pathway in acute and chronic rejection and highlight the benefits of targeting this pathway in combination with the use of conventional immunosuppressive agent.

Animals↗
PubMed2001

Raw oyster consumption and outbreaks of viral gastroenteritis in New Zealand: evidence for risk to the public's health.

OBJECTIVE: To investigate the relationship between consumption of raw Pacific half shell oysters and outbreaks of Norwalk-like virus (NLV) gastroenteritis in Auckland in the last third of 1999. METHOD: Ten outbreaks were investigated as retrospective cohorts using standardised questionnaires relating to food and drink exposures. Trace back of oysters and site inspections of implicated commercial growing areas were performed. Virological analyses compared oysters linked to outbreaks and faecal samples from cases. RESULTS: Eighty-six cases were identified, of whom 32 (37.2%) were confirmed NLV positive on faecal analysis. The summary risk estimate for illness among oyster consumers for all outbreaks was RR 8.23 (95% CI 4.55-14.90; p< 0.001) and in five of seven outbreaks permitting statistical analysis, the risk for those consuming raw oysters was greater than five-fold that of non-consumers. NLVs were identified in two batches of oysters from different growing areas, implicated in four outbreaks. In both the strain (Genogroup II/3 'Mexico-like virus') from cases matched that in the oysters from the same harvest batch. CONCLUSION: The epidemiological and virological evidence implicates oysters as the source of a number of outbreaks of NLV gastroenteritis. This is the first time NLVs have been identified in commercially farmed Pacific oysters in New Zealand. Sewage effluent from recreational boats was the likely source of faecal contamination of growing waters in one site. IMPLICATIONS: Combined use of virological and epidemiological methods have proved invaluable in investigating NLV outbreaks. Further research is needed into enteric viral contamination of commercial oyster farms.

Animals↗
PubMed2001

On the character of acoustic waves at the interface between hard and soft solids and liquids.

Laser ultrasonics is used to optically excite and detect acoustic waves at the interface between a liquid and a solid or coated solid. Several case studies show that this technique is feasible to investigate experimentally the theoretically predicted fundamental properties of different aspects of interface waves at liquid-solid interfaces and to characterize the elastic properties of soft solids. The theoretical prediction that the leaky Rayleigh (LR)-type root of the characteristic determinant becomes forbidden when the shear velocity of the solid lies below the bulk velocity of the liquid was experimentally confirmed. The depth profiling and nondestructive testing potential of Scholte waves was experimentally illustrated and explained by the properties of the wave displacement profile.

Journal Article↗
PubMed2001

Targeted deletion of CX(3)CR1 reveals a role for fractalkine in cardiac allograft rejection.

Fractalkine (Fk) is a structurally unusual member of the chemokine family. To determine its role in vivo, we generated mice with a targeted disruption of CX(3)CR1, the receptor for Fk. CX(3)CR1(-/-) mice were phenotypically indistinguishable from wild-type mice in a pathogen-free environment. In response to antibody-induced glomerulonephritis, CX(3)CR1(-/-) and CX(3)CR1(+/+) mice had similar levels of proteinuria and injury. CX(3)CR1(-/-) and CX(3)CR1(+/+) mice also developed similar levels of disease in myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis. We performed heterotopic MHC class I/II cardiac transplants from BALB/c mice into C57BL/6 mice. In the absence of cyclosporin A (CsA), there was no difference in graft survival time between CX(3)CR1(-/-) and CX(3)CR1(+/+) recipient mice. However, in the presence of subtherapeutic levels of CsA, graft survival time was significantly increased in the CX(3)CR1(-/-) mice. Characterization of cells infiltrating the grafts revealed a selective reduction in natural killer cells in the CX(3)CR1(-/-) recipients in the absence of CsA and a reduction in macrophages, natural killer cells, and other leukocytes in the presence of CsA. We conclude that Fk plays an important role in graft rejection. The development of CX(3)CR1 antagonists may allow reductions in the doses of immunosuppressive drugs used in transplantation.

Animals↗
PubMed2001

Temporal relationship between cytochrome c release and mitochondrial swelling during UV-induced apoptosis in living HeLa cells.

During apoptosis, cytochrome c is released from mitochondria to the cytosol to activate a caspase cascade, which commits the cell to the death process. It has been proposed that the release of cytochrome c is caused by a swelling of the mitochondrial matrix triggered by the apoptotic stimuli. To test this theory, we measured directly the dynamic re-distribution of green fluorescence protein (GFP)-tagged cytochrome c and morphological change of mitochondria within living HeLa cells during u.v.-induced apoptosis. We observed that mitochondria did not swell when cytochrome c was released from mitochondria to cytosol during apoptosis. Instead, mitochondria swelled to spherical shapes within 10 minutes of cytochrome c release. This finding strongly suggests that cytochrome c release in apoptosis was not caused by mitochondrial swelling. This conclusion was further supported in two separated experiments using an immunostaining method and carbonyl cyanide m-chlorophenyl-hydrazone (CCCP) treatment. In addition, we found evidence that cytochrome c was also released before mitochondrial swelling in apoptosis induced by other cell death-inducing treatments, including tumor necrosis factor (TNF) and actinomycin D.

Amino Acid Chloromethyl Ketones↗
PubMed2001

[A study of phenylketonuria heterozygotes screening in married population of Tianjin area].

OBJECTIVE: To find out a method that is simple and reliable for screening phenylketonuria(PKU) heterozygotes. METHODS: Detecting and analyzing plasma phenylalanine(Phe) and tyrosine(Tyr) from 101 known-PKU heterozygotes and 2023 married people by means of a high performance liquid chromatograph. RESULTS: Significant differences were observed between known- PKU heterozygotes and screening population in plasma Phe, Phe/Tyr and Phe(2)/Tyr. The values of plasma Phe, Phe/Tyr and Phe(2)/ Tyr from 94.1% known-PKU heterozygotes were higher than mean+2s of those values from screening population. According to the limits of mean+2s, 81 cases were screened out from the 2023 married people. It was the first time to get the actual heterozygote frequency of 4% from population. CONCLUSION: The biochemical method mentioned above is available for use in screening PKU heterozygotes.

Adult↗
PubMed2001

[Study on the awareness, treatment and control of hypertension in Qingdao rural residents].

In order to study the awareness, treatment and control rates and the risk factors of hypertension in Qingdao rural residents, a cluster random sampling method was used. Blood pressure measurement and questionnaire regarding risk factors for hypertension were applied to 3700 residents aged over 18. The standardized prevalence of hypertension in selected Qingdao rural residents was 19.5%. The awareness rate of hypertension was 31.5%. The main factors affecting awareness included age, cultural level, family income, family history of hypertension, and knowing the criteria for normal blood pressure (BP). The rate of taking regular treatment for hypertension was 35.7%. The factors affecting treatment for hypertension were age, culture level, times of measuring blood pressure (BP), suffering from complications of hypertension and family income. The awareness, treatment and control of hypertension should be improved and a comprehensive measure should be taken to prevent hypertension in Qingdao rural residents.

Adult↗
PubMed2001

[Intravesical instillation of cytotoxic T-lymphocytes induced by soluble tumor antigen in the prophylaxis of recurrence of bladder cancer].

OBJECTIVE: To explore a new method for preventing the recurrence of bladder cancer. METHODS: With the adjuvant of BCG, cytotoxic T-lymphocytes (CTLs) were induced from human peripheral blood mononuclear cells (PBMC) by bladder tumor soluble antigen which was extracted through salt-infiltrating biochemical procedures from autologous bladder tumor. Intravesical instillation of CTLs together with their supernatants after culture for 8 to 10 days was performed in 37 patients with superficial bladder cancer after surgery. The effects of the treatment were evaluated by endocytoscopy, pathological examinations and ELISA assays for the levels of cytokines IL-2, TNF-alpha and IFN-gamma in the patients' serum and urine. The distribution of T-lymphocyte subpopulations was also monitored by SAP immuno-histochemical techniques. RESULTS: The proportion of CD3+ and CD4+ T-lymphocyte subpopulations increased significantly while CD8+ T-lymphocyte subpopulation was stable. The ratio of CD4+ to CD8+ increased to 1.60 +/- 0.29. The levels of cytokines IL-2, TNF-alpha and IFN-gamma in serum and urine increased significantly, especially the level of TNF-alpha in urine. Pathological studies revealed that non-specific inflammation is the major change in the bladder mucosa after therapy. Follow-up for 6-26 months showed that 1 patient havd moderate heterogeneity in bladder mucosa. The recurrence rate was 2.7%. Side effects were not found except transient lower fever or hematuria. CONCLUSION: Intravesical insitillation of CTLs could effectively prevent the recurrence of superficial bladder cancer after the improvement of immunological reactivity in the whole body.

Administration, Intravesical↗
PubMed2001

[Effect of forest patch size and isolation on reproductive success of Great Tit in fragmented secondary-forests].

The effect of forest patch size and isolation on reproductive success of Great Tit (Parus major) in fragmented secondary-forests was studied in Zuojia Natural Protection Area of Jilin Province by collecting data on breeding success, clutch-size, laying date, egg weight, brood-size and number fledged of Great Tit in 18 large (20-30 hm2), medium (10-20 hm2), and small (6-10 hm2) patches, and two extensive forests (> 100 hm2). All the forest patches were GPS tested. The results showed that isolation had no effect on reproductive success of Great Tit, and Great Tit laid 7.2 days earlier in extensive forests than in all forest patches. Clutches in extensive forests and large forest patches were slightly larger than those in medium and small forest patches, and eggs were heavier in extensive forests than in the patches. Patch size had no effect on brood-size and number fledged. The lost rate of the nests was high in medium and small forest patches because of intense competition.

Animals↗
PubMed2001

[Spatial pattern and temporal dynamics of Atylotus pallitarsis population in Songnen Plain].

The spatial pattern and its time series dynamics of Atylotus pallitarsis population were examined in this paper. The results showed that the amount of this population was closely related to temperature and humidity, and its blood peak time appeared at about 14:00 o'clock in the afternoon. The population cattle was aggregated distribution and emigration throughout the day, the aggregated distribution pattern was loose mass community, the distribution of insects in the community was at random.

Animals↗
PubMed2001

[The dynamic change in the expression of interleukin 18 mRNA in the tissue of scalded rats after delayed resuscitation].

OBJECTIVE: To explore the dynamic change in the expression of interleukin 18 (IL-18) mRNA in the tissue of scalded rats after delayed resuscitation. METHODS: Wistar rats inflicted by 30% TBSA III degree scalding were employed as the model. Fifty-four rats were randomly divided into normal control (C), scalding and delayed resuscitation group (SD) and preventive group of selective decontamination of digestive tract (SDD) group. The RT-PCR was applied to determine the tissue contents of IL-18 mRNA in intestine, lungs, liver and kidneys at 2, 8, 16 and 24 PBHs. RESULTS: Plasma level of LPS increased significantly and reached summit level at 8 and 24 PBHs after delayed resuscitation after scalding (P < 0.01), but decreased obviously (P < 0.05) after the preventive application of SDD. Furthermore, the expression of tissue IL-18 mRNA in lungs, liver and kidneys since 2 PBHs increased evidently when compared to that before scalding and reached peak value at 8 PBH (P < 0.01) and lasted up to 24 PBHs. The expression of IL-18 mRNA could be inhibited to varying degrees by preventive application of SDD (P < 0.05-0.01). It was indicated by correlative analysis that plasma level of LPS was positively correlated to the expression of tissue IL-18 mRNA in intestine, lungs and liver (r = 0.298, 0.290 and 0.365 respectively with P < 0.05-0.01). CONCLUSION: The expression of tissue IL-18 mRNA in intestine, lungs, liver and kidneys increased significantly during early postburn stage and progressively enhanced thereafter. And the expression of tissue IL-18 mRNA in a variety of body tissue was significantly affected by post-traumatic endotoxemia.

Animals↗
PubMed2001

Confirmation of susceptibility gene loci on chromosome 1 in northern China Han families with type 2 diabetes.

OBJECTIVE: To confirm previous effort to identify type 2 diabetes susceptibility genes in a Northern Chinese population by conducting a new genome scan with both an increased number of type 2 diabetes families and a new set of microsatellite markers within the previously localized regions. METHODS: A genome scan method was applied. After multiplexed PCR, electrophoreses, genescan and genotyping analysis, we obtained size information for all loci, and then a further study was done by both parametric and non-parametric linkage analysis to investigate the P values and Z values of these loci. RESULTS: We surveyed 34 microsatellite markers which distributed within 5 regions along chromosome 1, and a total of 12,000 genotypes were screened. Evidence of linkage with diabetes was identified for 8 of the 34 loci. All P values of the 8 loci were lower than 0.05, and the highest Z value was 2.17. A very interesting finding is that all 5 markers at the p- terminal 1p36.3-1p36.23 region, spanning a long range of 16.9 cM, were identified to have a low P value of less than 0.05, which suggests that this region may contain multiple susceptibility genes. Regions 4 and 5 also confirmed the previous findings, and we narrowed these two regions to a 2.7 cM and 2.5 cM regions, respectively. CONCLUSIONS: We further confirmed the results gained in the previous genome-wide scan using an increased number of NIDDM families and a new set of microsatellite markers lying within the initially localized regions. The fact that all 5 loci at the p- terminal region displayed a low P value of less than 0.05 suggests that more than 1 susceptibility gene may reside in this region.

Chromosomes, Human, Pair 1↗
PubMed2001

Percutaneous balloon aortic valvuloplasty in the treatment of congenital valvular aortic stenosis in children.

OBJECTIVE: To assess the effect of the balloon valvuloplasty for for congenital valvular aortic stenosis (AS) in children. METHODS: A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV). The ratios of balloon/valve were 0.95 +/- 0.08 for 19 cases of typical AS and 1.00 +/- 0.11 for 8 cases of hypoplastic AS. The patients were evaluated by the gradients across aortic valves in pre- and post-PBAV and by echocardiogram during the follow-up period. RESULTS: Fifteen of 19 (78.9%) cases of typical AS had a better outcome and the gradient of the remaining 4 cases (26.7%) had increased after follow-up (delta P > 50 mm Hg). Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose. There was no moderate to severe aortic insufficiency (AI). CONCLUSION: The balloon aortic valvuloplasty provides safe and significant hemodynamic and clinical improvement in pediatric patients. The outcome of PBAV for typical AS is better than for hypoplastic AS.

Adolescent↗
PubMed2001

Percutaneous balloon angioplasty of coarctation of the aorta in children: 12-year follow-up results.

OBJECTIVE: To evaluate the efficiency of percutaneous balloon angioplasty of coarctation of the aorta in children and discuss its risk factors that can lead to poor long-term results. METHODS: From September 1987 to August 1999, 24 patients underwent 27 balloon angioplasty procedures for native or recurrent coarctation of the aorta at our institution. There were 19 patients with discrete (membranous) coarctation, 4 patients with long-segment and aortic arch hypoplasia, and 1 patient with postoperative recurrence. The balloon diameter was chosen not to exceed the diameter of the aorta proximal to the stenotic site (11.06 +/- 2.80 mm vs 11.78 +/- 3.18 mm), with the chosen diameter two to four times that of the stenotic segment (2.57 +/- 0.68 times). The patients have been followed up for half to twelve years (mean 6.2 +/- 2.8 years). Satisfactory result was defined as a reduction in the pressure gradient across the site of coarctation to < or = 20 mm Hg. RESULTS: The systolic pressure gradient across the coarctation site decreased from 48.17 +/- 14.68 mm Hg to 14.96 +/- 13.12 mm Hg (P < 0.01) and the diameter of the coarctation site increased from 4.66 +/- 2.43 mm to 8.80 +/- 3.32 mm (P < 0.01). Immediate satisfactory results were obtained in 19 patients (79%). Of the 5 patients with unsatisfactory results, 4 had aortic arch hypoplasia and 1 had membranous coarctation. Of the 19 patients with satisfactory results, 18 patients had membranous coarctation and 1 patient had recurrent postoperative coarctation. No aneurysm and other complications had occurred in any patients at the follow-ups. CONCLUSION: Percutaneous balloon angioplasty is an effective treatment alternative to surgery in most patients with recurrent postoperative or native membranous coarctation of the aorta. It should not be recommended for the coarctation of aortic arch hypoplasia.

Adolescent↗
PubMed2001

[Study of C807T polymorphism of the platelet collagen receptor alpha2 gene coding sequence in Suzhou Han population].

OBJECTIVE: To study the C807T polymorphism of the platelet collagen receptor alpha(2) gene coding sequence in Suzhou Han population. This polymorphism was associated with the expression density of integrin alpha(2)beta(1) on the platelet surface. METHODS: An amplified 1332 bp fragment of human alpha(2) gene from 110 unrelated individuals was analyzed by Bgl II and Ase I restriction assay. The resulting products were electrophoresed in 8% polyacrylamide gels and stained with ethidium bromide. RESULTS: The allelic frequencies were 0.291:0.709 for T807 allele: C807 allele in Suzhou Han population. The total theoretical heterozygous rate was 41%. The genotypic frequencies were 0.018:0.546:0.436 for homozygous 807T allele: heterozygous 807C/T allele: homozygous 807C allele. CONCLUSION: The C807T polymorphism of the platelet collagen receptor alpha2 gene in Suzhou Han population was different from that observed in other populations.

Asian People↗
PubMed2001

[Diagnostic significance of measurement of the receptor for urokinase-type plasminogen activator on granulocytes and in plasma from patients with paroxysmal nocturnal hemoglobinuria].

OBJECTIVE: To investigate the expression levels of the receptor for urokinase-type plasminogen activator (uPAR) on granulocytes and the soluble uPAR (suPAR) level in plasma from patients with paroxysmal nocturnal hemoglobinuria (PNH) and its clinical application in the diagnosis of this disorder. METHODS: Expression of uPAR, CD55 and CD59 was measured on granulocytes by using flow cytometry (FCM) and the level of suPAR in plasma by using immunoradiometric assay (IRMA) in 20 patients with PNH, 59 anemic patients with diagnoses other than PNH (18 with autoimmune hemolytic anemia, 6 with other hemolytic anemias, 26 with aplastic anemia and 9 with iron deficiency anemia) and 21 healthy individuals. RESULTS: In PNH patients, both the mean fluorescence intensity and percentage of positive fluorescence-activated granulocytes of uPAR, CD55 and CD59 were remarkably decreased, while in anemic patients with diagnoses other than PNH the results were not different when compared with those of the healthy individuals. The expression level of uPAR was reduced to the same extent as that of CD55 and CD59 on the PNH-affected granulocytes. In addition, some peak shape abnormalities (double peaks and/or peak tailing) in the histogram of fluorescence intensity were also found in PNH patients. The suPAR concentration of PNH plasma was (4.04 +/- 2.47) micrograms/L, being higher than that of the healthy individuals (1.73 +/- 0.96) micrograms/L (P < 0.01). And the percentage of positive fluorescence-activated granulocytes was inversely associated with the plasma suPAR level in PNH patients (r = -0.79, P < 0.01). CONCLUSION: It is suggested that measurement of expression level of uPAR on granulocytes with FCM and suPAR in plasma with IRMA would be alteanative specific techniques for the diagnosis of PNH.

Adolescent↗
PubMed2001

[Cytokine expression in effusions of secretory otitis media].

OBJECTIVE: To assess the cytokine level in effusions of secretary otitis media and it's relationship with clinical index. To further study the inflammatory mechanism of otitis media with effusion. METHOD: The concentration of TNF-alpha and TNFsolR II was quantitatively determined using enzyme-linked immunosorbent assay and it was correlated with clinical index in otitis media with effusion using stepwise regression analysis. RESULT: TNF-alpha and TNFsolR II was found in 100% effusions. Mean values of TNF-alpha were (3.42 +/- 2.25) ng/g total protein. Mean values of TNFsolR II were (405.80 +/- 216.53) ng/g total protein. Mean values of TNFsolR II index was (154.18 +/- 90.45) U. There was a significant decrease of TNFsolR II and TNFsolR II index in patients who recurred (P < 0.05). CONCLUSION: Cytokine TNF-alpha and TNFsolR II are important inflammatory medium which exist in all otitis media effusions. The decrease of the level of TNFsolR II and TNFsolR II index present significantly in middle ear effusions with recurrence, but there is no any relation of TNF-alpha in middle ear effusions with recurrence.

Adult↗