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J D Wang

Publications and source records attributed to J D Wang.

At least 19 recordsLinked to original sources
PubMed2006

Assessment of soil lead exposure in children in Shenyang, China.

Soil lead pollution is serious in Shenyang, China. The paper brings together the soil work, the bioaccessibility, and the blood lead data to assess the soil lead exposure in children in Shenyang, China. Approximately 15.25% of the samples were above China Environment Protection Agency guideline concentration for soil Pb to protect human from health risk (350 mgkg(-1)). Pb concentrations varied among use scenarios. The main lead contamination sources are industry emission and automobile exhaust. Bioaccessibility also varied among use scenarios. Children, who ingested soil from industrial area, public parks, kindergarten playground, and commercial area, are more susceptible to soil lead toxicity. The industrial area soil samples presented higher bioaccessibility compared to the other use scenario soil samples contaminated by automobile exhaust. The result also suggested a most significant linear relationship between the level of Pb contamination and the amount of Pb mobilized from soil into ingestion juice. Soil pH seemed to have insignificant influence on bioaccessibility in the present study. Bioaccessibility was mainly controlled by other factors that are not investigated in this study. A linear relationship between children blood lead and soil intestinal bioaccessibility was present in the study. Children who are 4-5 years old are more likely to demonstrate the significant relationship between soil lead bioaccessibility and blood lead as their behaviors place them at greatest risk of soil lead toxicity, and their blood lead levels are more likely to represent recent exposure.

Age Factors↗
PubMed2006

Update on clarithromycin resistance in Helicobacter pylori in Hong Kong and its effect on clarithromycin-based triple therapy.

AIM: To determine the antibiotic susceptibility of Helicobacter pylori and evaluate the efficacy of a clarithromycin-based triple therapy in relation to antibiotic resistance. METHODS: Consecutive patients referred for upper endoscopy due to dyspeptic symptoms were recruited. Gastric biopsies were obtained for the CLO test, histology and culture. Antibiotic susceptibility was assessed by the E-test. Patients with H. pylori infection received rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily for 7 days. RESULTS: Of 234 patients recruited, 124 were H. pylori-positive and culture was successful in 102 patients. The updated prevalences of resistance to clarithromycin, amoxicillin and metronidazole were 7.8, 0 and 39.2%, respectively. A total of 86 patients received 1-week triple therapy with rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1,000 mg, all twice daily, and 81 patients attended the follow-up test. Eradication rates by per-protocol and intention-to-treat analysis were 92.6 and 87.2%, respectively. The eradication rate by per protocol was significantly higher in patients with clarithromycin-susceptible strains than in those with clarithromycin-resistant strains (98.6 vs. 28.6%, p < 0.001). CONCLUSION: Clarithromycin resistance reduces the clinical efficacy of clarithromycin-based triple therapy. However, due to the low prevalence of clarithromycin resistance, clarithromycin-based therapy is still the first choice for clinical use.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2004

Effect of cyclo-oxygenase inhibitors on Helicobacter pylori susceptibility to metronidazole and clarithromycin.

BACKGROUND: We previously reported that aspirin inhibited Helicobacter pylori growth and suppressed the mutagenic effect of metronidazole. AIM: To determine the effects of a cyclo-oxygenase (COX)-2-specific inhibitor, SC-236, and a non-selective COX inhibitor, indometacin, on the growth, urease activity and antimicrobial susceptibility of H. pylori. METHODS: Three H. pylori reference strains, and 18 clinical isolates were treated with SC-236 or indometacin for 24 and 48 h. Growth, urease activity and susceptibility to clarithromycin and metronidazole of the bacteria were assessed by viable colony counting, spectrophotometry and E-test respectively. RESULTS: SC-236 and indometacin inhibited H. pylori growth in a dose-dependent manner with the lowest inhibitory concentrations of 0.03 and 0.1 mm, and the lethal concentrations of 0.09 and 0.3 mm, respectively. The numbers of CFU/mL in Brucella broth containing 0.09 mm SC-236 were 2 log lower at 24 h, and even 3 log lower at 48 h than that at 0 h (P = 0.035, compared with the vehicle control). Treatment of 0.3 mm indometacin reduced the number of CFU/mL by 1 log at 24 h compared with that at 0 h (P = 0.037 compared with the vehicle control). Helicobacter pylori urease activity began to decrease with 0.06 mm SC-236 at 24 h (P = 0.016), and 0.3 mm indometacin at 48 h (P = 0.025). MICs of metronidazole and clarithromycin against H. pylori were decreased significantly in the presence of 0.03 mm SC-236 or 0.1 mm indometacin (all P < 0.001). CONCLUSION: Both SC-236 and indometacin suppressed the growth and urease activity of H. pylori in a dose-dependent manner, and increased its susceptibility to the antibiotics.

Anti-Bacterial Agents↗
PubMed2003

Comparative evaluation of the BACTEC MGIT 960 system with solid medium for isolation of mycobacteria.

SETTING: The utilisation of new, rapid methods of diagnosis of tuberculosis is currently of great interest for tuberculosis control. This study was carried out in a teaching hospital in the eastern region of Taiwan. OBJECTIVE: The BACTEC MGIT 960 system was evaluated and compared with Lowenstein-Jensen (LJ) medium and Middlebrook 7H11 plate for recovery rate and time to detection of mycobacteria. DESIGN: A total of 1396 sputum samples were tested for the presence of mycobacteria. Specimens were processed and inoculated separately in the BACTEC MGIT 960 system, on LJ medium and 7H11 for comparative study. RESULTS: The BACTEC MGIT 960 detected 235 isolates (100%), followed by LJ with 205 isolates (87.2%) and 7H11 with 178 isolates (75.7%). The mean time to detection of Mycobacterium tuberculosis complex was 11.6 days with MGIT 960, 20.1 days with LJ, and 18.7 days with 7H11. The contamination rates were 15.1% with MGIT 960, 10.1% with LJ and 9.7% with 7H11. CONCLUSION: The BACTEC MGIT 960 system is a sensitive, rapid mycobacterial culturing system. However, the high contamination rate is a concern that should be carefully evaluated in the clinical setting.

Cell Culture Techniques↗
PubMed2002

An alternative method to enhance vagal activities and suppress sympathetic activities in humans.

Vagal withdrawal and/or sympathetic overactivity is always accompanied by various kinds of stress and is dangerous to the body. We proposed that mild acupuncture on the Sishencong points may effectively enhance vagal activities but suppress sympathetic regulations of the heart in humans. Experiments were carried out on nine healthy male volunteers, while they were lying in a quiet room during 2-4 P.M. Acupuncture was applied 2 mm deep into the skin using standard stainless acupuncture needles at the Sishencong points, which are located on the vertex of the head, each 1 cm away from Baihui (GV 20) in four directions. Four points around the temporal area were selected as control points. Forty minutes of precordial ECG signals before, during, and after acupuncture were recorded continuously. Frequency-domain analysis of the stationary RR intervals was performed to evaluate the total variance, high-frequency power (HF, 0.15-0.40 Hz) and low-frequency power (LF, 0.04-0.15 Hz) in normalized units (LF%). Acupuncture on the Sishencong points resulted in an increased HF but a decreased LF% compared with the before acupuncture stage. Such effects did not occur when manual acupuncture was applied to the control points. The differences in the heart rate dynamics between Sishencong and the control groups took place 10 min after initiation of acupuncture and persisted even after the removal of the needles. Based on these results, we concluded that manual acupuncture on the Sishencong points enhanced cardiac vagal and suppressed sympathetic activities in humans. The underlying mechanisms and potential applications warrant further investigations.

Acupuncture↗
PubMed2002

Validation of the World Health Organization quality of life instrument in patients with HIV infection.

We studied the reliability and validity of the World Health Organization quality of life (WHOQOL) assessment instrument in patients with human immunodeficiency virus (HIV) infection. WHOQOL-BREF was used to assess 136 HIV-infected outpatients. The results were analyzed and compared with data from 213 healthy persons. The Cronbach's alpha for internal consistency ranged from 0.74 to 0.85 across domains in HIV-infected patients. The test-retest reliability ranged from 0.64 to 0.79 across domains at average 4-week retest interval. Factor analysis identified four major factors: social, psychological, environment, and physical, consistent with the four domains of the instrument. The scores of all four domains correlated positively with self-evaluated health status and happiness (r range: 0.52-0.60 and 0.55-0.73 across domains, respectively), and correlated negatively with the number and severity of symptoms (r range: -0.40 to -0.47 and -0.41 to -0.52, respectively). The scores of physical, psychological and social domains, but not the environment domain, discriminated between healthy persons and HIV-infected patients (all p < 0.01). We conclude that the WHOQOL-BREF can be a useful quality-of-life instrument in patients with HIV infection.

Adult↗
PubMed2001

Rapid and simultaneous determination of mycophenolic acid and its glucuronide conjugate in human plasma by ion-pair reversed-phase high-performance liquid chromatography using isocratic elution.

A high-performance liquid chromatographic method has been developed for the simultaneous determination of mycophenolic acid (MPA) and its glucuronide conjugate (MPAG) in human plasma. The method involves protein precipitation with acetonitrile, followed by ion-pair reversed-phase chromatography on C18 column, with a 40 mM tetrabutyl ammonium bromide (TBA)-acetonitrile (65:35, v/v) mobile phase. A 20-microl volume of clear supernatant was injected after centrifugation, and the eluent was monitored at 304 nm. No interference was found either with endogenous substances or with many concurrently used drugs, indicating a good selectivity for the procedure. Calibration curves were linear over a concentration range of 0.5-20.0 microg/ml for MPA and 5-200 microg/ml for MPAG. The accuracy of the method is good, that is, the relative error is below 5%. The intra- and inter-day reproducibility of the analytical method is adequate with relative statistical deviations of 6% or below. The limits of quantification for MPA and MPAG were lower than 0.5 and 5.0 microg/ml, respectively, using 50 microl of plasma. The method was used to determine the pharmacokinetic parameters of MPA and MPAG following oral administration in a patient with renal transplantation.

Calibration↗
PubMed2001

Changes in lipid metabolism and effect of simvastatin in renal transplant recipients induced by cyclosporine or tacrolimus.

Hyperlipidemia is frequently developed following renal transplantation and results in worsening of the patient's prognosis. In study 1, the effects of immunosuppressants, cyclosporine (CsA) and tacrolimus on serum lipids were compared in-patients undergoing renal transplantation. The study included 32 cases of renal transplantation recipients who randomized to the CsA treatment group (15 patients) and the tacrolimus group (17 patients). Before and 1 month after the transplantation, we assessed the serum lipid levels, apolipoprotein levels, the concentrations of cholesterol in the respective lipoprotein fractions and the enzyme activities related to lipid-metabolism. The serum lipid levels in both groups were significantly increased at 1 month after renal transplantation. In the CsA group, there were significant increases in cholesterol contents in very-low-density lipoprotein (VLDL), LDL2 and HDL2 fractions, whereas, in the tacrolimus group, cholesterol content was increased in VLDL and HDL2 fractions. In study 2, 1 month after renal transplantation, 19 patients with hypercholesterolemia (total cholesterol (TC) >200 mg/dl) and hypertriglyceridemia (triglyceride (TG) >150 mg/dl) were treated with simvastatin 5-10 mg/day for 6 months. Simvastatin treatment significantly decreased serum TC (240+/-29-200+/-22 mg/dl, P<0.001), low-density lipoprotein cholesterol (LDL-C; 114+/-20-99+/-17 mg/dl, P<0.05) and TG levels (217+/-103-130+/-38 mg/dl, P<0.01). In addition, there were significant decreases in very-low-density lipoprotein cholesterol (VLDL-C; 53+/-20-34+/-15 mg/dl, P<0.001). The Cmax and AUC of simvastatin were increased about eight-fold, when simvastatin was given in combination with CsA. In contrast, no significant changes in simvastatin levels were observed when combination with tacrolimus. Although simvastatin levels were increased with CsA, there were no abnormal changes in renal and liver functions, creatinine phosphokinase (CPK) levels or in incidence of adverse effects.

Adult↗
PubMed2001

Rapid and simple determination of mycophenolic acid in human plasma by ion-pair RP-LC with fluorescence detection.

Mycophenolic acid (MPA) is an immunosuppressive drug given as the prodrug of mycophenolate mofetil (MMF). In order to investigate the pharmacokinetics of MPA, a simple, specific, sensitive and reliable method has been established for the quantitative determination of MPA in plasma from renal transplant recipients. The method involves a single-step protein precipitation procedure and a specific determination by ion-pair reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection. Separation was achieved on a C18 column (150 x 4.6 mm, 5 microm) with a mobile phase composed of borate buffer (pH 10.0; 50 mM)--acetonitrile--tetrabutylammonium bromide (200 mM) (75:25:1, v/v/v). The fluorescence detector was set at 310 (excitation) and 430 nm (emission). Following protein precipitation with ice-cold acetonitrile, clear supernatants (50 microl) were injected into the HPLC system. The retention time of MPA was approximately 4.5 min. The HPLC run time was 8 min. The assay was linear in concentration range 0.2-20.0 microg/ml for MPA in human plasma. Precision of the assay in the concentration range examined was from 0.89 to 3.21% for the intra-assay run and from 3.01 to 4.35% for the inter-assay run. A limit of detection was 0.05 microg/ml at a signal-to-noise ratio of 3. This validated method was then applied to the determination of MPA concentrations in renal transplant recipients after oral administration of 0.75 g of MMF.

Chromatography, High Pressure Liquid↗
PubMed2001

The differences between late graft loss group and long-term graft survival group in renal transplantation.

In renal transplantation, the long-term graft survival rate has not been improved. Until now, the differences between late graft loss and long-term graft survival have still not been estimated thoroughly. We have attempted to define clinical risk factors and parameters for late graft loss by comparing the differences in these two groups. Data from the Osaka University Database were assessed on 156 renal allografts during a 7-yr period. Thirty-six patients comprised the late graft loss group (patients in this group had graft function without need for dialysis for more than 3 yr post-transplantation, afterwards lost the allograft: 'loss group'). One hundred and twenty patients comprised the long-term graft survival group (patients in this group had graft function without need for dialysis until 31 December 1999: 'survival group'). Various immunological and non-immunological parameters were included in an univariate regression analysis. This analysis showed that donor age (P < 0.01), HLA mismatch number (P < 0.01) and a repeat of acute rejection (P < 0.01) were significant factors. Serum creatinine levels at 3 months (P = 0.01), proteinuria at 1 yr (P < 0.01) and antihypertensive treatment at 2 yr (P = 0.03) after transplantation were predictive of the risk of late graft loss. CsA trough concentration at 3-6 months (P < 0.05) and body mass index increase at 1 yr (P = 0.046) were elevated in the loss group. These results from a single centre suggest that immunological as well as non-immunological factors are associated with the pathogenesis of late graft loss.

Adult↗
PubMed2001

Impact of age on the injury pattern and survival of people with cervical cord injuries.

STUDY DESIGN: A retrospective, follow-up study. OBJECTIVES: To differentiate the injury pattern and survival of people with cervical cord injuries with onset at different ages. SETTING: Rehabilitation wards of a university hospital that is a tertiary referral center in Taipei, Taiwan. METHODS: The records of acute and traumatic cervical cord injury patients hospitalized from 1989 to 1997 were reviewed. All subjects received comprehensive rehabilitation programs during hospitalization. Their survival status at the end of follow-up was studied. RESULTS: Forty-seven of 109 (43.1%) people with cervical cord injuries were 50 years or older at onset. Older patients were more frequently injured by minor falls, resulting in more incomplete quadriplegia. They also showed fewer spinal fractures, and more demonstrated associated spondylosis and ossification of the posterior longitudinal ligament. Eleven (10.2%) subjects were deceased, found by a linkage to a death registration database at the end of follow-up. The significant predictor of survival status at follow-up was older age at injury using Cox proportional hazards model. CONCLUSION: Spinal cord injured patients had different injury patterns, demanding different preventative strategies. Those injured at older ages were at higher risk of mortality according to our study. SPONSORSHIP: This study was supported in part by grants from the National Taiwan University Hospital (89S2005), Taipei, Taiwan.

Adolescent↗
PubMed2001

Chronic cyclosporin-induced nephropathy.

AIMS: There is still no consensus about the prognostic influence of chronic nephropathy induced by low-dose maintenance therapy with cyclosporin. Our aim was to investigate the prognostic effect of cyclosporin nephropathy in Japanese renal transplant recipients. MATERIAL: We retrospectively investigated the clinical records of 1,323 kidney transplant recipients who received cyclosporin at 65 institutions in Japan from 1982 to 1991. METHOD: Renal biopsy was performed in 461 patients. RESULTS: At 5 years and 9 years after transplantation, the patients who had cyclosporin nephropathy associated with immunological rejection, glomerulonephritis, or both showed a significantly worse prognosis than those with cyclosporin nephropathy alone (p < 0.01). There was no significant difference in the loss of renal function at 9 years after transplantation between patients showing no abnormalities and patients with cyclosporin nephropathy alone. Even when cyclosporin nephropathy was absent, the long-term prognosis was unfavorable in recipients with immunological rejection or glomerulonephritis. CONCLUSIONS: These results suggest that cyclosporin nephropathy does not influence the prognosis of renal transplantation in patients on low-dose maintenance therapy with cyclosporin.

Chronic Disease↗
PubMed2001

[Sensitive and rapid analysis of nitrophenols and herbicides by capillary zone electrophoresis (CZE)].

11 Nitrophenols and some acidic herbicides have been separated by modified CZE. Good separation of such compounds can be achieved in less than 10 min by simply modifying the run buffer with organic solvents such as methanol, acetonitrile in a concentration of 40% (V/V). The limits of detection (LODs) for nitrophenols by UV-absorption at 215 nm were 0.5 mg/L-1.1 mg/L. Solid phase extraction was used to preconcentrate nitrophenols and some herbicides to reach an LOD at microgram/L levels. Typical samples have been analyzed.

Electrophoresis, Capillary↗
PubMed2001

[Purification of proteins in human plasma with new nylon affinity membranes].

A series of affinity membranes were prepared by using microporous nylon membrane as matrix and activation method with s-triazine and 1,4-butanediol diglycidyl ether, separately. Three proteins with clinic value, gamma-globulin, plasminogen and thrombin, were purified from human plasma by one step with affinity membrane chromatography. The purities of gamma-globulin purified were higher than 83%, and purification folds were higher than 5. The purity of gamma-globulin obtained was higher than that of standard human gamma-globulin. The efficiencies of gamma-globulin purification with affinity membranes prepared by two activation methods were equal. Plasminogen purified with affinity membranes prepared by s-triazine activation was higher than that by 1,4-butanediol diglycidyl ether activation. And SDS-PAGE analysis showed that the purities of gamma-globulin and plasminogen obtained were higher than that of the commercial product. In addition, the purification of thrombin from human plasma by one step with trypsin activation column and affinity membrane was studied. Thrombin with specific activity of 42 NIH unit/mg and 42.5 NIH unit/mg could be obtained from human plasma through affinity membranes prepared by s-triazine and 1,4-butanediol diglycidyl ether methods, respectively.

Blood Proteins↗
PubMed2001

[Preparation and evaluation of alkyl ether-bonded phase for reversed-phase high performance liquid chromatography].

A new silane coupling agent, beta-(3,4-epoxycyclohexyl)ethyltrimethoxy silane, was for the firsty time used to react with octanol, then the intermediate product was coupled onto porous silica to obtain a novel bonded phase for reversed-phase high performance liquid chromatography (RP-HPLC). Characterization of prepared packing was carried out with elemental analysis, solid-state 13C nuclear magnetic resonance spectrometry (NMR), Fourier transform infrared(FT-IR) spectroscopy. Chromatographic evaluations were carried out by using a mixture of organic compounds and methanol-water as the binary mobile phase. The results showed that the stationary phase has excellent chromatographic properties and resist to hydrolysis at a pH value between 2.5 and 7.5. The silanophilic activity of the OEBP was weakened because of the existence of the cyclohexyl group in the packing. It can be efficiently used for the separation of basic compounds.

Aminophylline↗
PubMed2001

[Preparation and evaluation of amide-octyl-bonded phase for the separation of basic substances in reversed-phase liquid chromatography].

A new bonded-phase, amide-octyl-bonded phase (AOBP), with an internal polar functional group-amide was firstly prepared in domestic by two-step reaction process. The amino phase was formed in the first step and further modified in the second step by attaching an alkyl chain via reaction of an acid chloride with the amino ligand. Characterization of prepared packing was carried out with elemental analysis and Fourier transform infrared (FTIR) spectrometry. Hydrophobicity, selectivity and silanophilic activity of AOBP were evaluated by using organic components including acidic, bascic and neutral analytes and methanol-water as binary mobile phase. The applicable ranges of pH and stability of AOBP were also evaluated. The results showed that AOBP has excellent chromatographic properties and resistance to hydrolysis between pH = 2.5-7.5, It can be used for the separation of basic solutes efficiently.

1-Octanol↗
PubMed2001

Epithelial maturation and extracellular matrix in reduced enamel epithelium.

OBJECTIVE: To evaluate epithelial-mesenchymal interactions in morphological homeostasis through histologically orientated observations on the reduced enamel in epithelium. STUDY DESIGN: Specimens were taken from impacted molar sites in 20 patients using the surgery. These were processed using standard histological, pathological and biochemical techniques. Slides were observed with a Nikon Eclipse E-600, Plan Apo piece, Microscopy, and photography was done using a Nikon Coolpix 990 digital camera. RESULTS: Radiolucent lesions displayed the supporting fibrous connective tissue wall with stratified squamous epithelium lining mostly. None of the specimens displayed prominent CAM 5.2, and anti-human K7 reacuvity, and PAS positive staining. CONCLUSION: While the results of this study suggest that the reduced enamel epithelium showed a lower tendency in cell cycle, it does indicate that a histologically oriented study of reduced enamel epithelium is needed for the understanding of epithelial-mesenchymal interactions in morphogenesis.

Dental Enamel↗