Biomedical subjects

C H Wu

Publications and source records attributed to C H Wu.

At least 145 records · Page 8Linked to original sources

PubMed1998

A population-based study of the prevalence and associated factors of diabetes mellitus in southern Taiwan.

Diabetes mellitus is one of the major health care problems in Taiwan, since the mortality rate has increased from 7.91 per 100,000 in 1980 to 35.1 per 100,000 in 1996. To determine the prevalence of diabetes in southern Taiwan and to investigate possible associated factors, a stratified systematic cluster sampling of 1638 subjects (780 men and 858 women) aged > or =20 years living in Tainan city was investigated with a standard 75-g oral glucose tolerance test. The crude prevalence of diabetes in Tainan was 9.0% (10.3% men and 7.9% women) and the age-adjusted prevalence was 9.2% (10.4% men and 8.1% women). The crude prevalence of IGT was 14.0% (13.8% men and 14.1% women), and the age-adjusted prevalence was 15.5% (15.0% men and 15.9% women). The prevalence of diabetes by using the revised new diagnostic criteria was 7.5%. The prevalence of diabetes and IGT increased significantly with age for both genders, although the rises in prevalence of IGT in women was less consistent. Diabetic and IGT subjects were older and had higher levels of BMI, triglyceride, systolic and diastolic blood pressure, and higher prevalence of obesity, hypertension, and dyslipidemia but indulged in less physical activity than non-diabetic subjects. The significant factors associated with the newly diagnosed diabetes were age, family history of DM, BMI, systolic blood pressure, physical activity, and serum triglyceride levels.

Adult↗

PubMed1998

Somatosensory evoked potentials in subclinical portosystemic encephalopathy: a comparison with psychometric tests.

We prospectively studied the role of somatosensory evoked potentials (SEPs) and psychometric tests in the assessment of subclinical portosystemic encephalopathy (PSE) in 61 cirrhotic patients with grade 0 PSE and 20 controls. Six additional uneducated controls underwent only psychometric tests. Median nerve-evoked cortical responses were recorded for N20-N65 interpeak latencies (IPLs). Psychometric tests were conducted within 4 hours of SEP testing. Seven (26.9%) controls and 30 (49.2%) cirrhotic patients had abnormal psychometric test results (writing sample tests, 20; five-point star tests, 17; number-connection tests, 19; and following-a-track tests, 18); seven controls and 25 cirrhotic patients had 6 or fewer years of education; 7 controls and 28 cirrhotics were older than 50 years of age. Cirrhotic patients (47.6 +/- 8.3 milliseconds) had higher N20-N65 IPLs than controls (40.2 +/- 3.0 milliseconds; P < .001). Twenty-nine (47.5%) cirrhotic patients had abnormal N20-N65 IPLs. Of the 26 cirrhotic patients with more than 6 years of education, 15 (57.7%) had abnormal N20-N65 IPLs and 5 (19.2%) had abnormal psychometric test results (P = .005). Our data show that N20-N65 IPLs of SEPs are helpful in the assessment of subclinical PSE; 47.5% of cirrhotic patients had subclinical PSE. Poorly educated and older subjects tended to have abnormal psychometric test results. SEPs were not affected by education and age and were more sensitive than psychometric tests in the assessment of subclinical PSE in better-educated cirrhotic patients.

Adult↗

PubMed1998

DNA ribonucleases that are active against intracellular hepatitis B viral RNA targets.

DNA ribonucleases directed against direct repeat 1 (DR1) and polyadenylation signal regions of hepatitis B virus (HBV) messages were prepared with phosphorothioate modifications and varying arm lengths. DNA ribonucleases modified throughout the entire molecule and in the target binding arms were completely protected from degradation after incubation with serum. DNA ribonuclease modified only at the 5' and 3' termini remained 92.9% intact after incubation. Molecules with no modification were degraded to 67.6% under the same conditions. However, modification of the entire molecule and in the recognition arms resulted in 99.8% and 98.4% inactivation of cleavage activity, respectively. Modification of only the termini resulted in retention of 20% to 40% of original activity. Lengthening each terminally modified arm from 9 to 11 nucleotides increased cleavage efficiency almost 10-fold. In Huh 7 cells, DR1-directed DNA ribonucleases with terminal modifications significantly suppressed HBV-luciferase fusion gene expression up to 48% of control. In contrast, DNA ribonucleases had no effect on a control construct lacking any HBV target sequences. Moreover, inactivated mutant and HCV-directed DNA ribonucleases had no significant effects on the HBV target. We conclude that resistance of DNA ribonucleases to degradation can be enhanced through phosphorothioate modification. Cleavage activity can be retained by limiting modification to the termini and lengthening the recognition arms. Such DNA ribonucleases can be made to specifically cleave target HBV RNA and substantially inhibit intracellular viral gene expression.

Base Sequence↗

PubMed1998

Targeted inhibition of hepatitis C virus-directed gene expression in human hepatoma cell lines.

BACKGROUND & AIMS: The 5'-nontranslated region (NTR) of hepatitis C virus (HCV) contains important elements that control HCV translation. The aim of this study was to determine whether antisense oligonucleotides against the NTR of the HCV genome can be targeted to inhibit HCV gene expression. METHODS: Antisense oligonucleotides directed against a sequence in the internal ribosomal binding site of the NTR (anti-III) and a portion of the NTR overlapping the core protein translational start site of HCV (anti-IV) were prepared. In transient transfections of a plasmid containing a luciferase gene immediately downstream from an HCV NTR insert, oligonucleotides anti-III and anti-IV in the form of asialoglycoprotein-polylysine complexes were administered to Huh7 cells, and luciferase activity generated by cytomegalovirus (CMV) HCVluc was measured. RESULTS: Anti-III inhibited luciferase activity by 75% and 99% at 0.01 mumol/L and 0.1 mumol/L, respectively. Similarly, anti-IV inhibited luciferase activity 88% and 99% at 0.01 mumol/L and 0.1 mumol/L, respectively. In cell lines stably transfected with CMV HCVluc plasmid, complexed anti-III inhibited luciferase activity in Huh7 cells by 20% at 10 mumol/L and 85% at 60 mumol/L, and was competable by an excess of asialoglycoprotein. CONCLUSIONS: Antisense oligonucleotides that bind to the NTR of HCV can be targeted by receptor-mediated endocytosis, and they specifically inhibit HCV-directed protein synthesis under intracellular conditions.

Carcinoma, Hepatocellular↗

PubMed1998

Detection of human papillomavirus types in cervical adenocarcinoma by the polymerase chain reaction.

OBJECTIVE: To determine the human papillomavirus (HPV) types in cervical adenocarcinoma of patients from Taiwan. METHODS: DNA was extracted from fixed tissues and polymerase chain reaction was performed in conjunction with a unique probe, pRSA I, allowing simultaneous detection of HPV types 6, 11, 16, 18, 31 and 33 from amplified HPV DNAs after endonuclease, RsaI, digestion. RESULTS: Of 69 tissues examined, 31.9% (22/69) were found to contain HPV DNA. Among 22 HPV-positive specimens, no HPV types 6, 11, 31 and 33 were detected. On the other hand, HPV 16 and HPV 18 were found in 11 (15.9%) and 10 (14.5%) of HPV-positive specimens, respectively. One specimen (1.5%) was found to contain both HPV 16 and 18 DNAs. CONCLUSIONS: Our findings support that HPV 18, along with HPV 16, may play a certain role in the adenocarcinoma pathogenesis of the uterine cervix.

Adenocarcinoma↗

PubMed1998

Relationship between glycosylated hemoglobin, blood pressure, serum lipid profiles and body fat distribution in healthy Chinese.

Obesity-related metabolic disorders have not been adequately addressed due to a failure to distinguish the importance of general obesity or body fat distribution in relation to atherosclerotic risk factors, especially in the less obese populations. To assess the relationship between general obesity (reflected by BMI, total body fat percentage and total adiposity), body fat distribution (reflected by WHR, default regions and ROIs of DEXA) and atherosclerotic risk factors in the Chinese population, a total of 872 healthy subjects (477 male and 395 female) were enrolled in the study. The results indicated that the android pattern of fat distribution, independent of general obesity, was positively correlated with blood pressure, atherogenic indices, fasting and OGTT 2-h plasma glucose, glycosylated hemoglobin (HbA1c), serum concentration of cholesterol, triglyceride, LDL cholesterol and negatively correlated with HDL cholesterol in both genders. The gender differences in patterns of body fat distribution and atherosclerotic risk factors remained significant after adjustments were made for age, BMI and total adiposity, although diminished after further adjustments for body fat distribution. In conclusion, body fat distribution, rather than general obesity, is more correlated with obesity-related atherosclerotic risk factors and sex-associated differences. ROIs measured by DEXA may be a useful method to evaluate sex-associated changes in body fat distribution and atherosclerotic risk factors in the healthy Chinese population.

Adipose Tissue↗

PubMed1998

Antenatal depiction of the fetal ear with three-dimensional ultrasonography.

OBJECTIVE: To evaluate the feasibility of examining the fetal ear with three-dimensional ultrasound. METHODS: In 125 pregnancies between 19 and 38 weeks of gestation, fetal ears were evaluated by three-dimensional ultrasound. The volume images with surface rendering were analyzed to depict the morphology, lying axis, orientation, and cranial location of the fetal ears. RESULTS: Three-dimensional images of one or both ears were successfully reconstructed in 105 fetuses. Among them, 18 fetuses had anomalous ears. The anomalous ears, including microtia, low-set ear with slope axis, abnormal ear orientation, and edematous ear, were confirmed after delivery. Three-dimensional ultrasound consistently displayed fetal ear abnormalities with greater accuracy and clarity. CONCLUSION: Because anomalous ears may be a part of complex fetal malformations, it is important to recognize ear abnormalities. Due to the complexity of the fetal ear, three-dimensional ultrasound offers more important information than two-dimensional ultrasound, which simply gives auricular geometry. We suggest that three-dimensional ultrasound can be used better to examine the fetal ear and may prove to be useful for prenatal diagnosis and genetic counseling.

Ear, External↗

PubMed1998

Toxicity and anaerobic biodegradability of pyridine and its derivatives under sulfidogenic conditions.

Attempts were made to correlate the chemical structure of pyridine and 15 pyridine derivatives with both their biodegradability by estuarine sediment microorganisms under anaerobic conditions and also with their toxicity to the marine bacterium Vibrio fischeri Beijerinck 1889 by using the Microtox bacterial assay. Among monosubstituted pyridines, comparisons of different substituents at positions C-2, C-3, or C-4 atom of the pyridine ring showed that isomers of carboxylpyridine (COOHPYR), hydroxypyridine (OHPYR), and cyanopyridine (CNPYR) were more susceptible to biotransformation than isomers of chloropyridine (ClPYR) and methylpyridine (CH3PYR) in anoxic estuarine sediment slurries under sulfidogenic conditions. Isomers with the functional group at the C-2 or C-3 atom of the pyridine ring were biotransformed faster than those with the same functional group at C-4. The only exception was 4-ClPYR, which was biotransformed within 130 days, while 2- and 3-ClPYR continued to persist in the anoxic sediment slurries. Median effect concentrations (EC50) of pyridine and pyridine derivatives were in the range of 0.027 to 49.1 mmol/L. Pyridine derivatives with -CN and -OH functional groups tended to be less toxic, while pyridine derivatives with -CH3, -Cl, and -COOH functional groups tended to be more toxic. Isomers with the substituent at C-2 were less toxic than the C-3 or C-4 isomers. There was no clear correlation between the pseudo-first-order rate constants for the microbial transformation of pyridine and its derivatives and their toxicity to the marine bacterium.

Anaerobiosis↗

PubMed1998

Cloning of the American cockroach Cr-PII allergens: evidence for the existence of cross-reactive allergens between species.

BACKGROUND: Previously, we have identified the 28 and 32 kd proteins as additional important allergens from the American cockroach (Periplaneta americana) Cr-PII allergenic fraction. OBJECTIVE: The aim of this study was the cloning of P. americana Cr-PII allergens. METHODS: A lambdagt22A cDNA library constructed from P. americana mRNA was packaged into Escherichia coli Y1090 (r-), and clones recognized by murine anti-Cr-PII monoclonal antibodies and human IgE antibodies were isolated, sequenced, and subcloned into pET 21 and expressed in E. coli BL21(DE3). RESULTS: Six Cr-PII-positive clones recognized by human IgE antibodies were isolated. Two clones, C6 and C17, were sequenced, and we found encoding proteins of 228 and 274 amino acids with no cysteine or any potential N-glycosylation site, with predicted masses of 25.8 and 31.14 kd, respectively. Both molecules contain internal repeated sequences with a 94% identity between them. C6 and C17 showed 59% and 77.3% skin reactivities, respectively, on 22 cockroach-sensitive atopic patients. Both clones were found to have 28.9% to 31.8% identities to ANG12 protein, a precursor of the African malaria mosquito (Anopheles gambiae) and 82.7% to 85.1% identity to a nucleotide sequence of the German cockroach (Blattella germanica) Bla g Bd90K allergen. The anti-C6 and anti-C17 antibodies were able to recognize Cr-PII, recombinant proteins, five commercial American extracts, and two German cockroach extracts. Moreover, the binding of anti-C6 and anti-C17 antibodies to recombinant protein can be inhibited by B. germanica crude extract. Furthermore, Northern blot analyses have shown that B. germanica mRNAs could be detected by both cDNA probes. CONCLUSION: Our findings provide the first evidence of antigenic cross-reactivity between P. americana and B. germanica allergens on molecular levels. The results will be a great aid in facilitating the epitope mapping and improving diagnostic and therapeutic reagents for both cockroach species.

Allergens↗

PubMed1998

Human portal serum stimulates cell proliferation in immature Schistosoma mansoni.

Schistosomula of Schistosoma mansoni were incubated in RPMI 1640 medium containing 10% fetal calf serum, 10% human portal venous or 10% human peripheral venous sera in the presence of bromodeoxyuridine (BrdU) in order to measure differences in cell proliferation. The rates of cell proliferation as expressed by BrdU labelling indices (BLI) were determined as a function of time of incubation by immunohistochemistry using monoclonal antibody to BrdU. Compared to schistosomula cultured in the presence of RPMI plus 10% fetal calf serum, BLIs were increased by 60% in the presence of human portal, but not in peripheral serum. This stimulatory effect was substantially reproduced by a fraction of portal serum with a molecular weight range between 1 and 50 kDa. However, in the presence of human peripheral venous serum, either whole or fractionated, schistosomula showed no significant difference compared to RPMI plus 10% fetal calf serum alone. Furthermore, human portal serum fractions of molecular weight greater than 50 kDa also revealed no significant difference relative to control. The results indicate that portal venous serum component(s) of a molecular weight range higher than most simple nutrients can greatly stimulate the rate of cell proliferation of Schistosoma mansoni schistosomula.

Animals↗

PubMed1998

Autologous CD34-selected blood progenitor cell transplants for patients with advanced multiple myeloma.

Fifty-five patients with advanced multiple myeloma received purified CD34-selected peripheral blood progenitor cell transplants following myeloablative chemotherapy. A median of 4.1 x 10(6) CD34 cells/kg (range 1.2-30.7) were infused after busulfan (14 mg/kg) and cyclophosphamide (120 mg/kg); granulocyte-macrophage colony-stimulating factor was used until hematopoietic recovery. Median time to neutrophils >0.5 x 10(9)/l and platelets >20 x 10(9)/l were 12 days (range 10-16 and 8-184 days, respectively). Median follow-up of survivors from the time of transplantation is 33 months (range 7 to 44 months). Thirty-one patients are alive, 19 progression-free. Median progression-free survival is 14 months. Actuarial 3-year progression-free and overall survival are 29+/-14% and 47+/-17%. CD34-selection of peripheral blood progenitor cells provides effective hematopoietic support with significant progression-free and overall survival.

Adult↗

PubMed1998

GeneFIND web server for protein family identification and information retrieval.

UNLABELLED: An integrated database and search system has been developed for protein family identification and information retrieval, as an approach to undertake the highly complex, genomic-scale problem of molecular sequence database search and organization. AVAILABILITY: http://diana.uthct.edu CONTACT: wu@uthct.edu

Amino Acid Sequence↗

PubMed1998

Cyclosporin inhibits nitric oxide production in medullary ascending limb cultured cells.

BACKGROUND: Nitric oxide (NO) has been shown to play a role in cyclosporin (CsA) nephrotoxicity, but its mechanism of action is still unclear. As inducible NO synthase (iNOS) mRNA has been found to be expressed in rat medullary thick ascending limb (mTAL) cells, we investigated the effects of CsA on NO production in a model of mouse cultured mTAL cells. MATERIALS AND METHODS: The experiments were carried out on sub-cultured cells derived from isolated mTAL microdissected from the kidney of C57BL/6 mice. The identification of the iNOS mRNA in mTAL microdissected segment and cultured cell was confirmed by RT PCR and RsaI digestion. Nitrite (NO2) released by mTAL cells was determined using the modified Griess reagent method and taken as an index of nitric oxide production. The cultured cells were treated with various concentrations of CsA and different signal transduction regulators to assess the effect and possible pathway(s) of action of CsA on NO production in mTAL cells. RESULTS: The basal production of NO by mTAL cells increased by 1.8-fold following incubation with bacterial lipopolysaccaride (LPS). Both aminoguanidine and L-NAME inhibited NO production. CsA (10-300 ng/ml) also inhibited NO production in a dose-dependent manner and prevented its increase induced by LPS. Phorbol 12-myristate 13-acetate (PMA), a PKC stimulator, enhanced slightly the production of NO under basal conditions and prevented the inhibitory action of CsA on NO production. These results suggest that the NO secreted by mouse cultured mTAL cells is dependent on the PKC pathway. CONCLUSION: These results show that CsA may down-regulate the production of NO by cultured mTAL cells expressing iNOS mRNA and that the PKC pathway is involved in this process.

Animals↗

PubMed1998

Integrated analyzer and classifier of glottographic signals.

Electroglottography (EGG) and photoglottography (PGG) are two plausible methods to study voice production for monitoring the patterns of laryngeal vibrations. It has been suggested that measures such as open quotient and speed quotient calculated from glottographic signals can provide useful information regarding pathological phonation. In this paper, an integrated analyzer and classifier of glottographic signals was implemented. The system makes it possible to calculate the measures from digitized EGG and PGG signals automatically in order to examine vocal fold abnormality. The system developed several techniques to extract features from glottographic signals and proposed a statistical classification method that can possibly aid the diagnosis process. To check the reliability of the system, a training set and a test set of glottographic signals from normal people and patients with recurrent/superior laryngeal paralysis were analyzed and classified by the system. The results showed that the system is a useful tool for quantitative study of phonatory pathophysiology and can be used by the examiner who is interested in the clinical examination of glottographic signals. Moreover, glottographic techniques may have some clinical applications in the quantitative documentation of phonatory function in patients with voice disorders but requires further evaluation before clinical application.

Electrodiagnosis↗

PubMed1998

Case report: Spontaneous isolated mesenteric fibromatosis presenting as megaduodenum.

A case of spontaneous isolated mesenteric fibromatosis presenting as megaduodenum is reported. The lesion was small, only 2 cm in its greatest diameter. However, because of its location near the ligament of Treitz and because of its characteristic infiltrative growth pattern, the tumour involved the distal duodenum and resulted in acute angulation and obstruction early in its course. We successfully resected the mass and the patient is in fair physical condition 6 months after operation.

Adult↗

PubMed1998

Hypersensitivity of bronchial asthmatics to cockroach in Taiwan. comparative study between American and German cockroaches.

This study was performed to test the hypersensitivity of asthmatics to American and German cockroaches, which are both common in Taiwan. A total of 236 asthmatic patients received skin prick test using allergen extracts from both American and German cockroaches, and 596 sera from asthmatic patients were analyzed for their specific IgE against German cockroach extract. The results of skin test showed that 39.4 and 36.4% asthmatic patients were hypersensitive to American and German cockroaches. Fifteen among 236 patients were only allergic to American cockroaches and 8 were only allergic to German cockroaches. Using the Pharmacia CAP system, 36% of the sera were found to contain the specific IgE to German cockroach extract. Eighty-nine sera positive for German cockroach extract were then tested for their reactivity to American cockroach extract using the fluoroallergosorbent test (FAST). Sixty among 89 (68%) of their sera contained American cockroach-specific IgE. The correlation coefficient between both parameters was r = 0.45. Immunoblot and immunoblot inhibition studies were performed to analyze the IgE-binding components and the cross-reactivity between American and German cockroaches. The results showed that there are different IgE-binding components between American and German cockroaches. Sera containing specific IgE to both species of cockroach were absorbed with both species of cockroach extracts. The specific IgE to German cockroaches can be absorbed by American cockroach extract in all selected sera and the specific IgE to American cockroaches can only partially be absorbed by German cockroaches. The nonabsorbed allergens in American cockroaches had molecular weights of 33 and 50 kD. In conclusion, one-third of the asthmatic population tested was allergic to cockroaches. Although most cockroach-hypersensitive patients were allergic to both American and German cockroaches, more asthmatic patients were allergic to American cockroaches in Taiwan. The use of non-crossreacting allergen in detecting American cockroach-specific IgE might be important not only for the diagnosis and treatment of cockroach hypersensitivity in asthmatics but also for the differentiation between German and American cockroach hypersensitivity.

Adolescent↗

PubMed1998

Usefulness of Doppler spectral analysis and power Doppler sonography in the differentiation of cervical lymphadenopathies.

OBJECTIVE: Our purpose was to depict the characteristics of the global vasculature of cervical lymphadenopathies and to clarify the efficiency of Doppler spectral analysis and power Doppler sonography in the differential diagnosis. SUBJECTS AND METHODS: Prospectively, 289 lymph node lesions underwent Doppler flow studies and were grouped as metastasis, lymphoma, tuberculosis, and benign lymphadenopathies. Sonographic assessments included vascular pattern and vascular density (presented as vascularity index) as revealed by power Doppler sonography. Vascular resistive index and pulsatility index were assessed by at least three flow samplings. Values of both the highest and the lowest resistance were analyzed. Vascularity index, resistive index, pulsatility index, nodal size, and age were correlated. RESULTS: Most benign lymphadenopathies (87%), tuberculous lymphadenopathies (72%), and lymphomas (71%) revealed an avascular or hilar vascular pattern. Vascular patterns of most metastatic lymphadenopathies (90%) were of spotted (26%), peripheral (11%), or mixed (53%) type. The vascularity indexes of metastatic lymphadenopathy (mean, 0.176) and lymphoma (mean, 0.122) were significantly higher than those of tuberculous and benign lymphadenopathy (mean, 0.054 and 0.042, respectively). In vascular resistance studies, the highest pulsatility index and resistive index in metastatic lymphadenopathy statistically exceeded those of benign lymphadenopathy, whereas no difference was found in the lowest values. Negative correlation was found between the vascularity index of metastatic lesions and their lowest vascular resistance, and positive correlation was found between vascularity index and nodal size in benign lymphadenopathies. CONCLUSION: In addition to vascular resistance assessed traditionally with Doppler spectral analysis, vascular pattern and vascular density assessed with power Doppler sonography can better differentiate the nature of lymphadenopathies.

Adolescent↗

PubMed1998

Preliminary use of endoluminal ultrasonography in assessment of middle ear with effusion.

Endoluminal ultrasonography with small-caliber and high-frequency transducer is suitable for transcanal assessment of middle ear with effusion. An endoluminal ultrasound transducer (size 6 French, 20 MHz) with a side-viewing scanning plane was used to image 12 ears of six children suspected of having effusion in the middle ear. Sonographic findings were compatible with those of operation in 10 diseased ears. One false-negative result was obtained, and one trial was aborted owing to trauma to the canal wall. The present study proves utility in demonstrating fluid behind the tympanic membrane. A promising use of endoluminal ultrasonography for middle ear evaluation might be expected if some modification could be made to the transducer.

Child↗