Biomedical subjects

Y H Yang

Publications and source records attributed to Y H Yang.

At least 19 recordsLinked to original sources

PubMed2006

High prevalence of albuminuria in population-based patients diagnosed with type 2 diabetes in the Shanghai downtown.

OBJECTIVE: The prevalence of albuminuria and the risk factors associated with albuminuria were evaluated among the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown. We also evaluated the variability of urinary albumin-to-creatinine ratio (ACR) among the three measurements and the relationship between diabetic retinopathy (DR) and albuminuria. METHODS: The 1039 Chinese patients diagnosed with type 2 diabetes aged over 30 were investigated by randomized cluster sampling in the Shanghai downtown and 1018 patients were analyzed in this study. Body mass measurements including height, weight, waist circumference and hip circumference, resting blood pressure, fasting blood measures, urinary ACR and the digitally stored fundus images were investigated. The prevalence of albuminuria was calculated and the risk factors associated with albuminuria were evaluated by stepwise logistic regression. The concordance of urinary ACR was evaluated by observed agreement. The relationship between albuminuria and DR was also evaluated. RESULTS: (1) The mean age of all patients was 66.10+/-11.54 years and the duration of diabetes was 7.89+/-7.16 years. (2) The prevalence of albuminuria was 49.6% among the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown, 41.4% with microalbuminuria and 8.2% with macroalbuminuria. (3) Microalbuminuria was significantly associated with systolic blood pressure, gender and waist circumference. Macroalbuminuria was significantly associated with systolic blood pressure and duration of diabetes. (4) Observed agreement among the three urinary ACR measurement for albuminuria staging was 73.3% (first versus second), 64.5% (first versus third) and 77.5% (second versus third). Observed agreement in the albuminuria staging between the single urinary ACR measurement and all three urinary ACR measurements was 85.8% (first versus all three), 87.6% (second versus all three) and 81.9% (third versus all three). (5) The percentage of DR in the macroalbuminuric group (59.2%) was significantly higher than that in the normalbuminuria group (16.1%) and microalbuminuria group (24.6%). (6) The macroalbuminuric patients with DR had significantly increased fasting blood glucose and HbA1c compared with the macroalbuminuric patients without DR. CONCLUSION: The prevalence of microalbuminuria observed in the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown reached up to 41.4% though the observations in our study might be representative of the diabetic patients of the Shanghai downtown. We agreed that at least two of the three urinary collections were done in a 3- to 6-month period because of the day-to-day variability in albumin excretion. The percentage of DR among the patients with macroalbuminuria was 59.2%, and the macroalbuminuric patients with the significantly high plasma glucose and DR were prone to diagnose DN.

Adult↗

PubMed2006

Involvement of norepinephrine in the hyperglycemic responses of the freshwater giant prawn, Macrobrachium rosenbergii, under cold shock.

Hyperglycemic response of freshwater giant prawn, Macrobrachium rosenbergii, under acute cold shock was investigated, and the involvement and stimulatory pathways of norepinephrine (NE) on induced-glycemia were further examined. Remarkable elevations in hemolymph glucose at comparable magnitude were observed in both intact and eyestalkless prawn under cold treatments, suggesting that hyperglycemic response of this species is not solely mediated through the actions of crustacean hyperglycemic hormone released from X-organ sinus gland complex on the target tissues, but NE is involved. Positive and significant correlations were noted between the hemolymph glucose titers and NE contents in both thoracic ganglia and the hemolymph, suggesting that NE plays a significant role in the hyperglycemic responses of this species under cold. Depressive effects of various adrenoceptor antagonists monitored in vivo and in vitro further suggest that the action of NE is primarily mediated through both alpha1- and beta1-adrenoceptors.

Amines↗

PubMed2006

Adjacent location of the bac gene and two-component regulatory system genes within the putative Streptococcus agalactiae pathogenicity island.

A chromosomal DNA fragment of 8992 bp in size that has not been previously identified in Streptococcus agalactiae, was cloned and sequenced from strain 98-D60C. In particular, this 8992-bp fragment contained genes homologous to the sensor histidine kinase gene and the DNA-binding response-regulator gene of Streptococcus pneumoniae, and S. agalactiae bac gene. Structural and genetic features of the 8992-bp fragment were highly similar to those specific for bacterial pathogenicity islands. Analysis of epidemiologically unrelated S. agalactiae strains revealed that this fragment was present only in bac gene-positive strains. The possible origin of the 8992-bp fragment in S. agalactiae and its significance for molecular mechanisms of "bacteria-host" interactions are discussed.

Antigens, Bacterial↗

PubMed2006

Craniofacial morphometric analysis of mandibular prognathism.

The purpose of this study was to provide more information about the morphological characteristics of the craniofacial complex in mandibular prognathism. Forty young adult males having mandibular prognathism were compared with 40 having normal occlusion. This was conducted to carry out geometric morphometric assessments to localize alterations, using Procrustes analysis and thin-plate spline analysis, in addition to conventional cephalometric techniques. Procrustes analysis indicated that the mean craniofacial, midfacial and mandibular morphology was significantly different in prognathic subjects compared with normal controls. This finding was corroborated by the multivariate Hotelling T(2)-test of cephalometric variables. Mandibular prognathism demonstrated a shorter and slightly retropositioned maxilla, a greater total length and anterior positioning of the mandible. Thin-plate spline analysis revealed a developmental diminution of the palatomaxillary region anteroposteriorly and a developmental elongation of the mandible anteroposteriorly, leading to the appearance of a prognathic mandibular profile. In conclusion, thin-plate spline analysis seems to provide a valuable supplement for conventional cephalometric analysis because the complex patterns of craniofacial shape change are visualized suggestive by means of grid deformations.

Adult↗

PubMed2006

Neuropsychiatric manifestations in pediatric systemic lupus erythematosus: a 20-year study.

The objective of this study was to investigate the manifestations, treatment and outcome of neuropsychiatric (NP) involvement in pediatric systemic lupus erythematosus (SLE) patients. The charts of 185 pediatric patients with SLE diagnosed between 1985 and 2005 in a tertiary referral hospital were retrospectively reviewed. NPSLE were defined using the American College of Rheumatology NPSLE case definitions. NPSLE developed in 34.6% (64/185) of the patients. The mean onset age was 15.2 years. Fourteen patients (21.9%) had NP manifestations on initial diagnosis of SLE. The median duration from the onset of SLE to NP manifestation was 11 months. The most frequent NP manifestations were seizure disorder (84.4%), ischemic stroke (28.1%) and psychosis (21.9%). However, the prevalence of manifestations of NPSLE might be underestimated by the retrospective design of our study. Higher mean C3/C4 levels, less percentage of anti-dsDNA antibodies elevation and higher percentage of elevated anticardiolipin antibodies were observed in NPSLE events than in non-NPSLE events (P < 0.05). The mortality rate of NPSLE patients decreased from 52.2% in 1985-1994 cohort to 27.8% in 1995-2005 cohort. In the past 10 years, the leading cause of death in NPSLE patients was NPSLE itself. NPSLE is common in pediatric SLE patients. It has diverse manifestations and a high mortality.

Adolescent↗

PubMed2005

CYP2K6 from zebrafish (Danio rerio): cloning, mapping, developmental/tissue expression, and aflatoxin B1 activation by baculovirus expressed enzyme.

A full-length zebrafish (Danio rerio) cytochrome P450 (CYP) 2K6 cDNA, was obtained (GenBank accession No. AF283813) through polymerase chain reaction cloning using degenerated primers based on a consensus CYP2 sequence and the heme-binding domain. This first CYP2K family member cloned from zebrafish had 1861 bp which contained 27 bp of 5'-untranslated region (5'-UTR), an open reading frame (ORF) of 1518 bp, and a 300 bp 3'-UTR with a poly A tail. The deduced 506 amino acid sequence of CYP2K6 had 63%, 62% and 59% identity with rainbow trout CYP2K1, CYP2K4 and CYP2K3, respectively; and 45%, 42%, and 42% identity with rabbit CYP2C1, human CYP2C19 and mouse CYP2C39, respectively. CYP2K6 mapped to 107.49cR on LG3 using the LN54 radiation hybrid panel. Its mRNA was detected at 5 days post-fertilization and in the adult liver and ovary among nine tissues examined. The ORF, including the 27 bp of the 5'-UTR, was cloned into pFastBac donor vector and then transferred into the baculovirus genome (bacmid DNA) in DH10Bac competent cells. The recombinant bacmid DNA was used to infect Spodoptera frugiperda insect cells to express the CYP2K6 protein (Bv-2K6). As its ortholog, rainbow trout Bv-2K1 [Yang, Y.H., Miranda, C.L., Henderson, M.C., Wang-Buhler, J.-L., Buhler, D.R., 2000. Heterologous expression of CYP2K1 and identification of the expressed protein (Bv-2K1) as lauric acid (omega-1)-hydroxylase and aflatoxin B1 exo-epoxidase. Drug Metab. Disp. 28,1279-83.], Bv-2K6 also catalyzed the conversion of aflatoxin B1 (AFB1) to its exo-8,9-epoxide as assessed by the trapping of a glutathione (GSH) adduct in the presence of a specific mouse alpha class glutathione S-transferase. The identity of the AFB1-GSH adduct was verified by liquid chromatography-mass spectrometry (LC-MS) and mass spectrometry-mass spectrometry (MS-MS) analysis. Although rainbow trout Bv-2K1 was capable of oxidizing lauric acid, zebrafish Bv-2K6 protein showed no activity against this substrate.

Aflatoxin B1↗

PubMed2004

Thermodynamics of diamond nucleation on the nanoscale.

To have a clear insight into the diamond nucleation upon the hydrothermal synthesis and the reduction of carbide (HSRC), we performed the thermodynamic approach on the nanoscale to elucidate the diamond nucleation taking place in HSRC supercritical-fluid systems taking into account the capillary effect of the nanosized curvature of the diamond critical nuclei, based on the carbon thermodynamic equilibrium phase diagram. These theoretical analyses showed that the nanosize-induced interior pressure of diamond nuclei could drive the metastable phase region of the diamond nucleation in HSRC into the new stable phase region of diamond in the carbon phase diagram. Accordingly, the diamond nucleation is preferable to the graphite phase formation in the competing growth between diamond and graphite upon HSRC. Meanwhile, we predicted that 400 MPa should be the threshold pressure for the diamond synthesis by HSRC in the metastable phase region of diamond, based on the proposed thermodynamic nucleation on the nanoscale.

Journal Article↗

PubMed2004

Research on solid-state fermentation on rice chaff with a microbial consortium.

A microbial consortium of Trichoderma reesei AS3.3711, Aspergillus niger 3.316 and Saccharomyces cerevisiaes AS2.399 was constructed to decomposed rice chaff on the basis of the characters of each microorganism and the mechanism of cellulases. In this experiment, rice chaff was pretreated before fermentation with NaOH so that the lignin structure of rice chaff was degraded and hemicellulose was dissolved partly, which remove the protection of lignin and hemicellulose on cellulose and demolish its special crystal structure. After pretreatment, rice chaff can be degraded more easily with the microbial consortium. The optimal technical paths and technological methods were achieved for intenerating rice chaff with the microbial consortium perfectly through orthogonal experiment. According to the technological methods, some experiments were done at 30 degrees C with pH 4.5. It was found that the highest filter paper enzyme activity (FPA) was 5.64 U/g and the ratio of cellulose degradation (RCD) was 28.05%.

Aspergillus niger↗

PubMed2004

Elevated serum levels of a c-erbB-2 oncogene product in oral squamous cell carcinoma patients.

OBJECTIVES: Amplification of the proto-oncogene c-erbB-2 (HER-2/neu) has been shown to be a prognostic marker in many kinds of cancer including oral squamous cell carcinoma (OSCC). In order to obtain further information on the c-erbB-2 gene product p185, it is necessary to quantify expression levels. In this study we used an enzyme-linked immunosorbent assay (ELISA) for the extracellular domain of p185 to determine whether a soluble oncoprotein fragment can be detected in the serum of OSCC patients. METHOD: Sera from 84 OSCC patients, 51 breast cancer patients (as positive controls), and 15 healthy controls were assayed in an ELISA. To study c-erbB-2 overexpression in OSCC, and breast cancer tissue samples we used an immunohistochemical technique. RESULTS: The mean serum value (ng/ml, mean/SD) for the normal controls was 8.46/1.29. We chose the 95% level of normal controls as a cut-off to distinguish individuals with elevated levels. The breast cancer patients' and OSCC patients' serum values were 13.83/6.82 and 13.1/4.56, respectively. Significant differences (P < 0.0001) were observed between normal control and OSCC, normal control and the breast cancer group. Immunohistochemically detectable p185 (intermediate to high) was noted in 30 of 61 OSCC, and 24 of 51 breast cancer patients. There was a trend of association of serum oncoprotein fragment levels with tumor stages, but not with tumor sizes, nodal stages, metastases, and oral habits including betel quid chewing, alcohol drinking and smoking in the OSCC group. CONCLUSION: The results of the present study raise the possibility that soluble c-erbB-2 protein levels in serum is a useful parameter for monitoring the disease status as well as the effect of therapy on patients with OSCC.

Adult↗

PubMed2004

Sera from children with active Henoch-Schönlein purpura can enhance the production of interleukin 8 by human umbilical venous endothelial cells.

OBJECTIVE: To investigate the ability of sera from children with active Henoch-Schonlein purpura (HSP) to enhance endothelial interleukin (IL) 8 production and intercellular adhesion molecule (ICAM)-1 expression. METHODS: Nine children with active HSP and nine normal healthy children were enrolled. IL8 serum levels of patients and controls at different stages were analysed. Production of IL8 and expression of ICAM-1 by human umbilical venous endothelial cells were detected (ELISA for IL8, flow cytometry for ICAM-1) and compared under various stimuli, including sera of patients at different stages, sera of controls, and medium alone. RESULTS: Serum levels of IL8 were increased at the acute stage. Levels of IL8 in supernatants from human umbilical venous endothelial cells (HUVEC) co-cultured with sera from children with active HSP were significantly higher than those from HUVEC without any treatment (p = 0.001), HUVEC treated with inactive sera (p = 0.004), and HUVEC treated with sera from healthy controls (p = 0.004). Sera from patients and from controls did not enhance the expression of ICAM-1 on HUVEC. CONCLUSIONS: Some factors may be present in sera from children with active HSP that could activate endothelial cells to produce IL8. This process may account, in part, for the mechanisms of perivascular neutrophil infiltration and leucocytosis in HSP.

Acute Disease↗

PubMed2004

Clinical diagnosis of group B streptococci by scpB gene based PCR.

BACKGROUND & OBJECTIVES: The goal of the present study was to improve and simplify the diagnosis of Streptococcus agalactiae (group B Streptococcus, GBS) infection for routine clinical practice. METHODS: A total of 71 clinical samples were tested by microbiologic culture, counter immunoelectrophoresis (CIE) and PCR described in the literature. Southern hybridization was accomplished with the Enzo(TM) "DNA Labeling and Detection Kit", Roche (Germany). The computer techniques were used for selection of the specific primers and for analysis of the sizes of PCR products. RESULTS: The primers for the regions around the 51 bp deletion in C5a peptidase gene (scpB) of GBS were selected. PCR analysis revealed the 255 bp amplification fragment in GBS, 306 bp fragment in groups A and G streptococci (GAS, GGS) and did not reveal any fragments in other bacterial species. Among 71 urine and serum clinical samples tested, none were found to be GBS positive by microbiologic culture, 16 samples by CIE, 36 by PCR. The specificity of amplification was confirmed by Southern hybridization. INTERPRETATION & CONCLUSION: The 51 bp deletion in scpB gene in comparison with scpA and scpG genes can be used as a diagnostic tool for identification of GBS. The 51 bp deletion based PCR proved to be faster and more reliable test than microbiologic culture or CIE.

Adhesins, Bacterial↗

PubMed2003

The presence of insertion elements IS861 and IS1548 in group B streptococci.

The presence of insertion elements (IS) IS861 and IS1548 in the collection of 211 Streptococcus agalactiae strains isolated from pregnant women and dairy cows was assayed. IS861 was found in 67 human strains (59%) and 36 bovine strains (37%), IS1548 in 13 human strains (12%) and 16 bovine strains (16%). Two combinations, IS861+ IS1548- and IS861- IS1548-, were widely distributed in both human and bovine strains. The copy number and the restriction fragment length polymorphism (RFLP) of the two IS were determined in human group B streptococcus (GBS) strains. A minimum of 8 copies of IS1548 were detected in GBS strains while the copy number of IS861 varied from 1 to 9. The number of different hybridizing patterns with IS861 and IS1548 probes was 9 and 6, respectively. These hybridization patterns were divided into several clusters. All strains with IS were also clustered according to pulsed field-gel electrophoresis (PFGE) patterns. A correlation was found between the results of PFGE- and IS-based clustering.

Animals↗

PubMed2003

Apolipoprotein E in Taiwan Chinese patients with dementia.

To clarify whether Alzheimer's disease (AD) and vascular dementia (VaD) share the same risk factors in Taiwan Chinese patients. Using the criteria of the NINCDS- ADRDA and NINDS-AIREN, 154 AD patients, 30 VaD patients, and 112 controls were enrolled. Their apolipoprotein E (ApoE) genes, extracted from peripheral blood leukocytes, were analyzed. The epsilon4 allele frequency was significantly higher in AD patients than in the control group. The odds ratio of carrying at least one copy of the epsilon4 allele in AD patients is 2.7 compared with control subjects. There was no significant difference between the VaD patients and the control subjects in their ApoE epsilon4 or epsilon2 allele frequency. The present study demonstrates a strong association between the ApoE epsilon4 allele and AD, but not between the ApoE epsilon4 allele and VaD. This suggests that AD and VaD do not share the same pathogenesis and deserve further investigation.

Aged↗

PubMed2002

Chromosomal analysis of group B streptococcal clinical strains; bac gene-positive strains are genetically homogenous.

A collection of 45 epidemiologically unrelated Streptococcus agalactiae strains (group B Streptococcus, GBS), belonging to different serotypes, isolated from pregnant women in China and Russia was studied. Strains were characterized by pulsed-field gel electrophoresis (PFGE) employing hybridization with nine genes potentially involved in virulence. Molecular sizes of GBS genomes varied from 2030 to 2290 kb. Location of the genes under study bac, bca, glnA, scpB, cyl, hylB, lmb, scaA and cfb on the GBS genomes was found to be conserved irrelevant to the serotype. Potential virulence genes scpB, hylB, lmb were located on a 91-kb SmaI fragment that is equal to 4.5% of total genome. Ribotyping of the strains under study revealed three different HindIII, nine EcoRI and 12 PvuII ribotypes among 45 strains. A strong correlation between the PvuII ribotype and the presence of the bac gene was observed, with 21 of 22 bac-positive strains belonging to the same PvuII ribotype P1. PFGE patterns of bac-positive strains were also similar. The possibility of close genetic relatedness of all bac-positive strains is discussed.

Antigens, Bacterial↗

PubMed2002

Genetic diversity of Cheju horses (Equus caballus) determined by using mitochondrial DNA D-loop polymorphism.

We used sequence polymorphism of the mitochondrial DNA D-loop (968 bp excluding the tandem repeat region) to determine genetic diversity of horses inhabiting Cheju (a southern island of Korea). Seventeen haplotypes with frequencies from 1.5 to 21.5% were found among 65 Cheju horse samples. Genetic diversity (h) of the 17 haplotypes was calculated to be 0.91, indicating that the extant Cheju horse population consists of diverse genetic groups in their maternal lineage. Phylogenetic analysis showed that 17 types of Cheju (D-loop sequences determined), 5 Mongolian, 6 Arabian, 3 Belgian, 2 Tsushima, 2 Yunnan, 1 Przewalskii, and 3 Thoroughbred horses (published sequences for the latter seven breeds) showed that Cheju horses were distributed into many different clusters in the tree. Four Mongolian horses clustered with separate Cheju horse groups, showing that some Cheju horses are clearly of Mongolian origin. The analysis of partial sequences (284 bp) of the D-loop of 109 horses showed that Thoroughbred, Mongolian, Lipizzan, and Arabian breeds are as diverse as Cheju horses. Our data together with others suggest that most horse breeds tested with reasonably sufficient numbers of samples are diverse in their maternal lineages and also are not uniquely different from each other.

Animals↗

PubMed2002

Antimicrobial susceptibility of Haemophilus influenzae among children in Beijing, China, 1999-2000.

UNLABELLED: A study on the nasopharyngeal carriage and antimicrobial susceptibility of Haemophilus influenza among children was conducted in Beijing Children's Hospital from April to May 2000. The study included 292 children between 1 and 60 mo of age with acute upper respiratory tract infection. Nasopharyngeal swabs from these patients were cultured, and 105 Haemophilus influenzae strains were isolated, 3 of which were type b. Antibiotic susceptibility of the strains was determined using disk diffusion and E-tests and the results compared with those of isolates from children with pneumonia in 1999. The carriage rate of Haemophilus influenzae was 36.0% (105/292). It was found that 4.8% and 1.0% of isolates were resistant to ampicillin and cefaclor, respectively, and 5.7%, 16.2% and 77.1% were resistant to chloramphenicol, tetracycline, and sulphamethoxazole/trimethoprim, respectively. Amoxicillin/clavulanic acid, cefuroxime, ceftriaxone, azithromycin, and clarithromycin were uniformly active to all strains. Compared with the data from 1999, there was a significant increase in resistance to tetracycline (from 12.7% in 1999 to 16.2%) and sulphamethoxazole/trimethoprim (from 40.5% in 1999 to 77.1%). CONCLUSION: H. influenzae isolates from outpatients in Beijing Children's Hospital had low ampicillin resistance and were sensitive to amoxicillin/clavulanic acid. Sulphamethoxazole/ trimethoprim resistance rates increased rapidly compared with those in the 1999 data. Further surveillance investigations are important for the choice of empiric therapy of acute respiratory tract infection.

Ampicillin Resistance↗

PubMed2001

Enhanced IL-18 expression in common skin tumors.

Interleukin-18 (IL-18) has been found to have multiple effects upon various cells involved in inflammatory response. Recently we reported that B16 murine melanoma cells are able to produce IL-18, which is involved in the regulation of intracellular reactive oxygen intermediates (ROI) and Fas-ligand expression, indicating that IL-18 plays key role in the tumor activity of melanoma. In this study, we investigated the pattern of IL-18 expression in the human system. IL-18 production was tested by enzyme linked immunosorbent assay (ELISA) assay in various tumor cell lines, including Raji (Burkitt's lymphoma), IM-9 (B lymphoblast), Jurkat (acute T cell leukemia), SK-MES-1 (squamous cell carcinoma (SCC) cell line), SK-MEL-2, G-361, DM-4, and DX-3 (melanoma cell lines). ELISA tests showed that IL-18 was highly expressed in malignant skin tumors such as SK-MES-1, SK-MEL-2, G-361, DM-4, and DX-3 cell lines, thus suggesting that IL-18 production may be associated with the malignancy of skin tumors. Here, we report that enhanced IL-18 expression is positively correlated with malignant skin tumors such as SCC and melanoma, suggesting the importance role of IL-18 in malignancy of skin tumors. Taken together, expression of IL-18 by tumor cells in human skin tissue may provide an important clue to understand the pathogenesis of malignant skin tumors.

Basal Cell Carcinoma↗

PubMed2001

Tissue-type plasminogen activator deficiency exacerbates arthritis.

Fibrin deposition, cell migration, and tissue remodeling are key components in the lesions of inflammatory joint diseases, such as rheumatoid arthritis. The plasminogen activators (PAs), namely, tissue-type PA (t-PA) and urokinase PA, are implicated in these aspects of an inflammatory response, although their precise roles are yet to be defined. We therefore used gene-deficient mice to explore their role in a two-stage arthritis model involving intraarticular methylated BSA injection, followed by systemic IL-1 treatment. We report in this study that both t-PA and urokinase PA are protective for the mild arthritis induced by intraarticular methylated BSA injection alone, since absence of either of them exacerbates the response; following s.c. IL-1 injection, t-PA(-/-) mice had particularly severe disease. Fibrin deposition appeared to parallel disease severity under the various conditions, suggesting that PA-mediated fibrinolysis may be normally playing a protective role in inflammatory joint disease.

Animals↗