Biomedical subjects

Y Ruan

Publications and source records attributed to Y Ruan.

At least 19 recordsLinked to original sources

PubMed2003

Association study of neuregulin 1 gene with schizophrenia.

A number of studies have indicated that 8p22-p12 is likely to harbor schizophrenia susceptibility loci. In this region, the candidate gene of interest, neuregulin 1 (NRG1), may play a role in the pathogenesis of schizophrenia. Then in the present study, we performed the linkage disequilibrium to determine the association between three genetic variants (SNPs: rs3924999, rs2954041, SNP8NRG221533) on NRG1 gene and schizophrenia in 246 Chinese Han schizophrenic family trios using PCR-based restriction fragment length polymorphism method and denaturing high-performance liquid chromatography. The transmission disequilibrium test analysis for each variant showed a significant difference between two transmitted alleles even after Bonferroni correction (rs3924999, P=0.007752; rs2954041, P=0.0009309; SNP8NRG221533, P=0.012606). The global chi(2) test for haplotype transmission also revealed a strong association (chi(2)=46.068, df=7, P&<0.000001). Our results suggest that the NRG1 gene may play a role in conferring susceptibility to the disease.

Adult↗

PubMed2001

A monoclonal antibody that induces neuronal apoptosis binds a metastasis marker.

The cell surface molecules controlling apoptosis in cortical neurons are largely unknown. A monoclonal antibody was derived that induces cultured neocortical neurons to undergo apoptosis. A Fab fragment of the antibody, however, lacked the ability to induce cell death. The antigen was purified, and characterized by compositional analysis, fast atom bombardment (FAB) mass spectrometry, sequential exoglycosidase treatments, methylation analysis, and (1)H-nuclear magnetic resonance spectroscopy, proving to be isoglobotetraosylceramide (IsoGb4). IsoGb4 has been shown previously to be a metastasis marker, antibodies against which block metastases in a mammary adenocarcinoma model (S. A. Carlsen et al., Cancer Res., 53: 2906-2911, 1993). Addition of the purified antigen to cells lacking this glycolipid demonstrated that it is capable of functioning as a portable apoptosis-transducing molecule. Intracellular ceramide levels were increased after the treatment with the apoptosis-inducing antibody, but the membrane sphingomyelin level remained unchanged. Fumonisin B1 inhibited both the ceramide increase and the apoptosis induced via IsoGb4, which indicated that the ceramide synthase pathway is likely to be involved in apoptosis induction by IsoGb4.

Animals↗

PubMed2001

Ethanol hypersensitivity and olfactory discrimination defect in mice lacking a homolog of Drosophila neuralized.

Neurogenic genes in the Notch receptor-mediated signaling pathway play important roles in neuronal cell fate specification as well as neuronal differentiation. The Drosophila neuralized gene is one of the neurogenic genes. We have cloned a mouse homolog of Drosophila neuralized, m-neu1, and found that the m-neu1 transcript is expressed in differentiated neurons. Mice deficient for m-neu1 are viable and morphologically normal, but exhibit specific defects in olfactory discrimination and hypersensitivity to ethanol. These findings reveal an essential role of m-neu1 in ensuring proper processing of certain information in the adult brain.

Amino Acid Sequence↗

PubMed2001

Model TJ-IV computer-assisted vectorcardiogram analysis system.

During last 16 years we have successfully developed the computer-assisted vectorcardiogram analysis systems: model TJ-I, TJ-II, and TJ-III, but some technical problems remained unresolved, such as the recognition accuracy for vectorcardiograms, measurement of the parameters of complicated QRS waves, the ratio of T loop length to width, and the area of spatial vectors etc. A new system, model TJ-IV was designed to resolve these technical problems. The system was equipped with a 586 computer with a CPU of 120 MHz. Special new low-noise amplifier was employed and C language was used for programming. Three graph recognition techniques were used to enhance the accuracy of VCG recognition. 32 orthogonal electrocardiograms and vectorcardiograms were displayed and printed, and 566 parameters of vectorcardiograms were calculated. Our results with 150 cases showed that the system had high accuracy of graph recognition, and parameter calculation and the results were essentially consistent with those of manipulative methods. We were led to concluded when compared with TJ-III system, the new version has higher accuracy of processing and measurement for vectorcardiograms, is able to process more vectorcardiographic parameters, with higher processing speed.

Adult↗

PubMed2001

Short-coupled variant of torsade de pointes.

Presented in this paper were 3 cases of a special kind of polymorphic ventricular tachycardia (VT). The clinical manifestation was recurrent syncope without organic heart disease. The electrocardiogram (ECG) was characterized by normal QT intervals with short-coupled variant of torsade de pointes. The efficacy of treatment with class I, II, III antiarrhythmic drugs was not apparent but verapamil had an excellent therapeutic effect for it. This kind of VT had a high incidence of sudden death, so it was very important for physicians to identify and treat it promptly with long-term verapamil. The mechanism of short-coupled variant of torsade de pointes was unclear. It probably had some relationship with triggered activity or imbalance of autonomic nervous system.

Adult↗

PubMed2001

Suppressive effect of locally produced interleukin-10 on respiratory syncytial virus infection.

Interleukin (IL)-10 is known to be a multifunctional cytokine. This study was designed to evaluate the role of IL-10 during respiratory syncytial virus (RSV) infection using a C57BL/6 transgenic (TG) mouse model in which the expression of murine IL-10 cDNA was regulated by a human salivary amylase promoter (IL-10 TG mice). These mice expressed a large amount of IL-10 in the nasal mucosa and in salivary glands. Viral replication in the respiratory tract after intranasal infection with RSV was suppressed significantly in IL-10 TG mice compared to non-transgenic controls. This suppression was IL-10 specific, because it was prevented by treating mice with neutralizing anti-IL-10 antibodies. We also found that IL-10-stimulated T cells displayed cytotoxic activity against infected murine nasal epithelial cells. Previous data indicated that IL-10 induces Fas ligand (L) expression on mouse T cells. Taken together, these data suggest that Fas/Fas L mediated cytotoxicity is involved in the suppression of RSV replication observed in IL-10 TG mice after intranasal infection.

Animals↗

PubMed2001

[Comparative study on antibody levels of vaccination group and control group after 4 years of immunized with type B inactivated vaccine against hemorrhagic fever with renal syndrome].

OBJECTIVE: To compare the antibody level of vaccine group and control group in a randomized, controlled trial of type B inactivated vaccine against hemorrhagic fever with renal syndrome(HFRS) in Jiande County of Zhejiang Province and to find out if there is enhancement of subclinical infection about type B inactivated vaccine against HFRS. METHODS: The number of sera collected (July 1994-July 1998) in vaccine group immunized type B inactivated vaccine against HFRS and control group were 305 and 283 persons in Jiande County respectively, and indirect immunofluorescent antibody method(IFAT) was used for testing the titer of HFRS IgG in sera. The cut-off values were determined on IFA titer of the second sera in control group with positive and negative IFA before vaccine was given respectively, and the subclinical infection of positive and negative IFA of the first sera in vaccine group was evaluated. RESULTS: When taking different cut-off values of subclinical infection, there were no statistical differences in HFRS IFA positive rates between vaccine group and control group of positive IFA in the first sera. In vaccine group and control group of negative IFA before vaccine given, also the IFA positive rates were not statistically different in these groups. There were no statistical differences of IFA GMT and IFA sero-negative rate between vaccine group and control group. CONCLUSIONS: The investigation showed there was no statistical difference in antibody level between vaccine group and control group, so there could not be enhancement of subclinical infection of vaccine group receiving type B inactivated vaccine against HFRS.

Adolescent↗

PubMed2001

[Experiences of surgical treatment with cicatricial laryngotracheal atresia: report of 48 cases].

OBJECTIVE: In order to improve the treatment methods of laryngotracheal atresia, several improved surgical procedures were used. METHOD: From 1986, the 48 patients with laryngotracheal atresia accepted surgical treatment in our hospital. Laryngo-fissure with laser cauterization of the glottis, laryngotracheal reconstruction using surgical flaps with or without particles, laryngo-tracheal reconstruction using itself's cicatrices, tracheal end-to-end anastomosis, two-stage laryngotracheal reconstruction using aqueduct method, bronchotracheal reconstruction through the chest. RESULT: 46/48 cases were cured breathing without tracheal cannula. Following-up survey is 1-12 years. CONCLUSION: The treatment of cicatricial laryngotracheal atresia was difficult, but if the surgical methods were selected carefully according to the situation of each patient, we also can get a good result.

Adolescent↗

PubMed2000

Folic acid protects SWV/Fnn embryo fibroblasts against arsenic toxicity.

It has been proposed that arsenic exerts its toxic effects, in part, by perturbing cellular methyl metabolism. Based on the hypothesis that folic acid treatment will attenuate the cytotoxic and growth inhibitory effects of arsenic, SWV/Fnn embryo fibroblasts were cultured in media supplemented with various concentrations of folic acid during treatment with sodium arsenite or dimethylarsinic acid (DMA). It was found that folic acid protects SWV/Fnn embryo fibroblasts from sodium arsenite and DMA cytotoxicity in a dose-dependent manner. In contrast, folic acid supplementation has no effect on toxicity resulting from treatment with ethanol or staurosporine, suggesting that folic acid is not generally protective against necrosis and apoptosis. Although folic acid protects against acute arsenic toxicity, this agent shows a modest and delayed ability to attenuate the growth inhibitory effect of arsenic on these cells. These results support a model in which perturbations of methyl metabolism contribute to the acute cytotoxicity of arsenic.

Animals↗

PubMed2000

Pulmonary artery perfusion with protective solution reduces lung injury after cardiopulmonary bypass.

BACKGROUND: The inflammatory response and higher temperature of lung tissue during cardiopulmonary bypass can result in lung injury. This study was to evaluate the protective effect of pulmonary perfusion with hypothermic antiinflammatory solution on lung function after cardiopulmonary bypass. METHODS: Twelve adult mongrel dogs were randomly divided into two groups. The procedure was carried out through a midline sternotomy, cardiopulmonary bypass was established using cannulas placed in the ascending aorta, superior vena cava, and right atrium near the entrance of the inferior vena cava. After the ascending aorta was clamped and cardioplegic solution infused, the right lung was perfused through a cannula placed in the right pulmonary artery with 4 degrees C lactated Ringer's solution in the control group (n = 6) and with 4 degrees C protective solution in the antiinflammation group (n = 6). Antiinflammatory solution consisted of anisodamine, L-arginine, aprotinin, glucose-insulin-potassium, and phosphate buffer. Plasma malondialdehyde, white blood cell counts, and lung function were measured at different time point before and after cardiopulmonary bypass; lung biopsies were also taken. RESULTS: Peak airway pressure increased dramatically in the control group after cardiopulmonary bypass when compared with the antiinflammation group at four different time points (24 +/- 1, 25 +/- 2, 26 +/- 2, 27 +/- 2 cm H2O versus 17 +/- 2, 18 +/- 1, 17 +/- 1, 18 +/- 1 cm H2O; all p < 0.01). Pulmonary vascular resistance increased significantly in the control group than in the antiinflammation group at 5 and 60 minutes after cardiopulmonary bypass (1,282 +/- 62 dynes x s x cm(-5) versus 845 +/- 86 dynes x s x cm(-5) and 1,269 +/- 124 dynes x s x cm(-5) versus 852 +/- 149 dynes x s x cm(-5), p < 0.05). Right pulmonary venous oxygen tension (PvO2) in the antiinflammation group was higher than in the control group at 60 minutes after cardiopulmonary bypass (628 +/- 33.3 mm Hg versus 393 +/- 85.9 mm Hg, p < 0.05). The ratio of white blood cells in the right atrial and the right pulmonary venous blood was lower in the antiinflammation group than in the control group at 5 minutes after the clamp was removed (p < 0.05). Malondialdehyde were lower in the antiinflammation group at 5 and 90 minutes after the clamp was removed (p < 0.01 and p < 0.05, respectively). Histologic examination revealed that the left lung from both groups had marked intraalveolar edema and abundant intraalveolar neutrophils, whereas the right lung in the control group showed moderate injury and the antiinflammation group had normal pulmonary parenchyma. CONCLUSIONS: Pulmonary artery perfusion using hypothermic protective solution can reduce lung injury after cardiopulmonary bypass.

Animals↗

PubMed2000

Estrogen receptors and the activity of nitric oxide synthase in the artery of female rats receiving hormone replacement therapy.

OBJECTIVE: To observe the expression of estrogen receptor and the activity of NOS in the arteries of female rats receiving estrogen replacement therapy. METHODS: Seventy-two female rats were randomly divided into four groups: group A: sham-ovariectomy; group B: ovariectomy; group C: ovariectomy with estrogen replacement therapy (benzoate estradiol, 5 microg i.m. once in 2 days); group D: ovariectomy with estrogen and progesterone replacement therapy (benzoate estradiol, 5 microg i.m. once in 2 days and progesterone, 1 mg i.m. once in 2 days). The rats were killed after 2 months. The receptor-binding assay was adopted to measure the estrogen receptors in the arteries of the rats, and the activity of NOS in the arteries was assessed by the hemoglobin reductase method. RESULTS: The ER number and NOS activity in the arteries of the ovariectomized group are less than those in sham-ovariectomy group (p<0.05). The ER number and NOS activity in the arteries of groups C and D are larger and higher than those in the ovariectomized group (p<0.05). No significant differences in the ER number and NOS activity were observed between groups C and D. CONCLUSION: The ER number and NOS activity in the rat artery significantly decrease after ovariectomy, while hormone replacement therapy can significantly increase the artery NOS activity and retain the ER number in the artery of the ovariectomized rats to normal level. The result may contribute to explaining the beneficial effect of estrogen in the prevention of coronary artery diseases in postmenopausal women.

Animals↗

PubMed2000

Plasma endothelin-1 levels and circulating endothelial cells in patients with aortoarteritis.

To investigate the correlation between plasma endothelin-1 (ET-1), circulating endothelial cells (CECs), and the disease activity in patients with aortoarteritis. In this study, radioimmunoassay was used to measure plasma levels of ET-1 in 56 patients with aortoarteritis. Circulating endothelial cell counts were also carried out as an indicator of vessel wall lesions. The plasma levels of ET-1 and CECs in the active disease patient group were significantly higher than those in inactive patient group (p<0.001). A significant positive correlation was found between plasma ET-1 levels and erythrocyte sedimentation rates (ESRs) in patients with aortoarteritis (r=0.645, p<0.001), as well as CECs (r=0.876, p<0.001). These results suggested that the ET-1 secreted during the active stages of aortoarteritis may cause constriction and proliferation of vascular smooth muscle cells, thus contributing to the pathogenesis of luminal narrowing. The increased CECs might serve as a marker of disease activity.

Adult↗

PubMed2000

[Construction of linkage map and mapping resistance gene of Scterotinia scterotiorum in Brassica napus].

Scterotinia scterotiorum (Lib.) de by is a world-wide disease, which seriously decreases the yield and the quality of oil of rapeseed. Mapping resistance genes of S. scterotiorum is of vital effect to breed new elite cultivars resisting the disease. In this paper, we reported that a RAPD linkage map was constructed, including 193 RAPD markers, 19 linkage groups and covering 1,324 cM, by using Mapmaker 3.0. On the basis of map, and resistance genes, Sc1, Sc2 and Sc3, were located in 4th, 8th and 18th linkage groups. Among three QTLs, Sc2 has the characteristics of major gene with explained 29%. The three QTLs together explained about 56% of phenotypic variation.

Brassica↗

PubMed2000

[Correlation study of TGF beta expression in diethylnitrosamine-induced rat liver cancer and mast cells in its vicinity].

OBJECTIVE: To study the correlation between tumor cell expression of TGF beta and the amount of surrounding mast cells in hepatocarcinogenesis. METHODS: Hepatocarcinoma was induced by diethylnitrosamine (DENA) in rats. The expression of TGF beta was examined immunohistochemically, and mast cells were identified by Alcian blue staining. The results were undergone cell imaging analysis. RESULTS: Positive expression of TGF beta was observed in the cytoplasm of the hepatocarcinoma cells. The intensity of expression differd in various groups of experiment. There was a positive correlation between the intensity of the TGF beta expression in hepatocarcinoma cells and the amount of mast cells surrounding the tumor nodules (P < 0.01). CONCLUSION: Mast cell infiltration in DENA-induced rat hepatoma may be due to the chemotactic effect of TGF beta expressed in tumor cells.

Animals↗

PubMed2000

[A case-control study on the risk factors of epidemic hemorrhagic fever].

OBJECTIVE: To study the risk factors of epidemic hemorrhagic fever (EHF). METHODS: A 1:1 matched case-control study was conducted to analyse EHF risk factors. RESULTS: One hundred and eighty-five matched pairs were investigated. Five factors were associated with risks of the disease, including rodent activity in house, farm working, travel, annual average income of an individual and ground material of the house, when chi(2) test and logistic regression model were processed respectively. The coefficients of rodent activity in house, farm working, travel, annual average income of an individual and ground material of the house in multivariable Logistic regression model were 1.377, 1.687, 1.630, -1.216 and -0.888, respectively, when P value < 0.05 was observed. CONCLUSIONS: Factors as high average income of individuals, brick or cement used as material of the ground in the house, seemed to be protective factors of EHF, which were important to the control and prevention of EHF.

Adult↗

PubMed2000

[Safety and immunogenicity of inactivated bivalent EHF vaccine in humans].

OBJECTIVE: Safety and immunogenicity of inactivated bivalent EHF vaccine in humans were evaluated in the epidemic area of Zhejiang province, China. METHODS: Susceptible persons with negative anti-EHF were selected in Jiande county, Zhejiang province to receive 3 doses of inactivated bivalent EHF vaccine at 0, 7, 28 days. A booster injection was given one year after the primary immunization. Antibody responses were measured in human volunteers by IFA and MCPENT. Local and general reactions were recorded within 72 hours after each vaccination by physicians. RESULTS: Two weeks after the primary vaccination, 99.04% of the subjects developed significant hantavirus antibody titre measured by IFA which had a 37.34% drop one year after the primary vaccination. Seroconversion rate increased to 100% two weeks after the booster dose. Neutralising antibody titres paralleled this trend with 100% of vaccine recipients producing neutralising antibody two weeks after the primary doses. However, it dropped to 80% one year after the primary vaccination. One hundred percent of the vaccine recipients started to respond two weeks after boosting. The geometric mean titre (GMT) of neutralising antibody against 76 - 118 and UR were 18.27 +/- 2.21 and 12.47 +/- 2.16 respectively after the primary injections, but it increased to 37.09 +/- 2.24 and 32.61 +/- 2.05 respectively after the secondary immunization. General and local reaction rates were 0.46% and 1.98%, with no severe side effects observed in the vaccinees. CONCLUSION: The vaccine was well tolerated and could induce good humoral immune response.

Antibodies, Viral↗

PubMed2000

[Drinking water types, microcystins and colorectal cancer].

OBJECTIVE: To assess the relationship between microcystins (a blue-green algal toxin) in drinking water and colorectal cancer. METHODS: Eight townships were randomly selected as study sites in Haining city of Zhejiang province, China. Four hundred and eight colon and rectum carcinoma cases diagnosed from 1977 to 1996 were identified from cancer registry in the study sites. A retrospective survey on types of drinking water of all 408 cases was conducted. Population data and drinking water sources data were provided by local household registration and local health institution, respectively. Water samples from different sources (well, tap-water, river and pond) were collected and microcystins concentrations were measured by an indirect competitive ELISA method. RESULTS: The incidence rates of colorectal cancer were significantly higher among people drinking river or pond water than those who drank well water or tap-water in both males and females. And comparing with other sources to well water, the relative risks (RR) were much higher for people using river water (7.94) and pond water (7.70). The positive detection rates (> 50 pg/ml) of microcystin in well, tap-water, river and pond water were 0.00%, 0.00%, 36.23% and 17.14% respectively. The highest concentrations of microcystins were 1 083.43 pg/ml (river) and 1 937.94 pg/ml (pond) in the positive samples. Microcystins concentrations in river and pond were significantly higher than the concentrations in well and tap water (P < 0.01). The Spearman rank correlation analysis showed that in the study sites, the microcystins concentrations of river and pond water were positively correlated with the incidence of colorectal cancer (r = 0.881, P < 0.01). CONCLUSION: Drinking surface water (river or pond) is one of the risk factors for colorectal cancer. Microcystins may be associated with incidence of colorectal cancer. It is suggested that further study should be carried out to clarify the relationship between colorectal cancer and microcystin in drinking water.

Bacterial Toxins↗

PubMed2000

[Changes of surfactant A and B in alveolar type II cells in hamster with elastase-induced emphysema].

OBJECTIVE: To observe the changes of surfactant A and B (SP-A and SP-B) in alveolar type II cells of lungs in hamsters with elastase-induced emphysema. METHODS: After intratracheal instilling of elastase, hamsters were killed at the 30th, 60th and 90th day of the experiment respectively. Slides of lung tissue were examined under light microscope and measured by calculating the mean linear intercepts. Then the slides were stained under immunohistochemistry procedures and measured by using a morphometric analysis system. Meanwhile, slides were also checked by electron microscopy. RESULTS: In comparison with the normal group, MLI of the elastase group was significantly increased (P < 0.01). Immunohistochemistry showed that the percentage of both SP-A and SP-B positive cells was significantly decreased 30 days after the intratracheal instilling of elastase (from 48.0% +/- 3.0% to 9.5% +/- 4.0% and from 28.0% +/- 4.0% to 13.3% +/- 4.1%, respectively; P < 0.01), however, a time-dependent recovery 90 days after instilling was seen. Electron microscopy showed a significantly decrease of the number of lamellae. CONCLUSION: The decrease of SP-A and SP-B in alveolar type II cells seems to play an important role in the development of emphysema.

Animals↗