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Biomedical subjects

W Chiang

Publications and source records attributed to W Chiang.

At least 19 recordsLinked to original sources
PubMed2003

In vitro antiviral activities of Caesalpinia pulcherrima and its related flavonoids.

The aim of this study was to search for new antiviral agents from Chinese herbal medicine. Pure flavonoids and aqueous extracts of Caesalpinia pulcherrima Swartz were used in experiments to test their influence on a series of viruses, namely herpesviruses (HSV-1, HSV-2) and adenoviruses (ADV-3, ADV-8, ADV-11). The EC50 was defined as the concentration required to achieve 50% protection against virus-induced cytopathic effects, and the selectivity index (SI) was determined as the ratio of CC50 (concentration of 50% cellular cytotoxicity) to EC50. Results showed that aqueous extracts of C. pulcherrima and its related quercetin possessed a broad-spectrum antiviral activity. Among them, the strongest activities against ADV-8 were fruit and seed (EC50 = 41.2 mg/l, SI = 83.2), stem and leaf (EC50 = 61.8 mg/l, SI = 52.1) and flower (EC50 = 177.9 mg/l, SI = 15.5), whereas quercetin possessed the strongest anti-ADV-3 activity (EC50 = 24.3 mg/l, SI = 20.4). In conclusion, some compounds of C. pulcherrima which possess antiviral activities may be derived from the flavonoid of quercetin. The mode of action of quercetin against HSV-1 and ADV-3 was found to be at the early stage of multiplication and with SI values greater than 20, suggesting the potential use of this compound for treatment of the infection caused by these two viruses.

Antiviral Agents↗
PubMed2002

Antiviral activity of Plantago major extracts and related compounds in vitro.

Plantago major L., a popular traditional Chinese medicine, has long been used for treating various diseases varying from cold to viral hepatitis. The aim of present study was to examine the antiviral activity of aqueous extract and pure compounds of P. major. Studies were conducted on a series of viruses, namely herpesviruses (HSV-1, HSV-2) and adenoviruses (ADV-3, ADV-8, ADV-11). The antiviral activity of EC50 was defined as the concentration achieved 50% cyto-protection against virus infection and the selectivity index (SI) was determined by the ratio of CC50 (concentration of 50% cellular cytotoxicity) to EC50. Results showed that aqueous extract of P. major possessed only a slight anti-herpes virus activity. In contrast, certain pure compounds belonging to the five different classes of chemicals found in extracts of this plant exhibited potent antiviral activity. Among them, caffeic acid exhibited the strongest activity against HSV-1 (EC50=15.3 microg/ml, SI=671), HSV-2 (EC50=87.3 microg/ml, SI=118) and ADV-3 (EC50=14.2 microg/ml, SI=727), whereas chlorogenic acid possessed the strongest anti-ADV-11 (EC50=13.3 microg/ml, SI=301) activity. The present study concludes that pure compounds of P. major, which possess antiviral activities are mainly derived from the phenolic compounds, especially caffeic acid. Its mode of action against HSV-2 and ADV-3 was found to be at multiplication stages (postinfection of HSV-1: 0-12 h; ADV-3: 0-2 h), and with SI values greater than 400, suggesting the potential use of this compound for treatment of the infection by these two viruses.

Adenoviridae↗
PubMed2001

GAD65 antibody prevalence and association with thyroid antibodies, HLA-DR in Chinese children with type 1 diabetes mellitus.

Persistent humoral autoimmunity to the enzyme glutamic acid decarboxylase (GAD) has been described in a substantial proportion of patients with type 1 diabetes mellitus. Higher prevalence of GAD antibody in diabetes patients using a new radioligand-binding assay with recombinant human GAD65 antibodies (GAD65Ab) has been seen in several studies. Using this method, we have reassessed the prevalence of GAD65Ab and investigated the association of GAD65Ab with HbA1C values, C-peptide values, HLA-DR typing and thyroid autoimmune antibody in 70 Chinese children with type 1 diabetes mellitus (mean age of onset 8.21+/-3.84 years, mean duration 3.39+/-2.54 years). Our result revealed that GAD65 antibodies were present in 54.3% (38/70) of diabetes children. There was no significant difference in gender, diabetes onset and duration, HbA1c, C-peptide concentration and frequencies of HLA DR3, DR4, DR9, DR3/DR4, DR3/DR9 and DR4/DR9 genotypes between GAD65Ab+ and GAD65Ab- groups. There was no negative correlation between GAD65Ab values and duration of diabetes in those with GAD65Ab positivity (r=-0.239, P>0.05). The frequencies of antimicrosomal and anti-thyroglobulin antibodies in GAD65Ab+ (13.5,8.1%, respectively) were not different from GAD65- patients (9.4,12.5%, respectively).

Adolescent↗
PubMed2001

Antagonism of free-radical-induced damage of adlay seed and its antiproliferative effect in human histolytic lymphoma U937 monocytic cells.

The goal of our current research was to investigate the antioxidative effects of methanolic extracts from different parts of adlay seed and their antiproliferative activity in malignant human cells. The methanolic extracts from different parts of adlay seeds were from the hull (AHM), testa (ATM), bran (ABM), and polished adlay (PAM). AHM exhibited greater capacity to scavenge superoxide anion radicals in the PMS-NADH system than ATM, ABM, or PAM. The scavenging capacities of AHM and ATM on hydrogen peroxides were about 20% at a dose of 250 microg/mL. Using the method of deoxyribose degradation to assess damage caused by hydroxyl radicals, AHM was found to inhibit damage in deoxyribose at a higher concentration. However, ATM, ABM, and PAM exhibited prooxidative activity at the same concentration. The inhibitory effect on enzymatic oxidation of xanthine to uric acid was found to follow the order AHM > ATM =. ABM. However, PAM was inactive. All test samples were positive for inhibition of TPA-induced free radical formation on neutrophil-like leukocytes and were found to follow the order AHM > ATM > ABM > PAM. When human histolytic lymphoma U937 monocytic cells were exposed to tert-butyl hydroperoxide, AHM protected the cells against the cytotoxicity caused by tert-butyl hydroperoxide. In addition, AHM exhibited antiproliferative activity against human histolytic lymphoma U937 monocytic cells in a dose-dependent manner. The antiproliferative properties of AHM appear to be attributable to its induction of apoptotic cell death as determined by flow cytometry. These results show that AHM displays multiple antioxidant effects and induces apoptosis of malignant human cells.

Antineoplastic Agents↗
PubMed2001

The epidemiology of the homeless population and its impact on an urban emergency department.

OBJECTIVES: To characterize the homeless adult population of an urban emergency department (ED) and study the medical, psychiatric, and social factors that contribute to homelessness. METHODS: A prospective, case-control survey of all homeless adult patients presenting to an urban, tertiary care ED and a random set of non-homeless controls over an eight-week period during summer 1999. Research assistants administered a 50-item questionnaire and were trained in assessing dentition and triceps skin-fold thickness. INCLUSION CRITERIA: all homeless adults who consented to participate. Homelessness was defined as being present for any person not residing at a private address, group home, or drug treatment program. Randomly selected controls were concurrently enrolled with a 3:1 homeless:control rate. EXCLUSION CRITERIA: critically ill, injured, or incapacitated patients, or patients <21 years of age. Univariate analysis with appropriate statistical tests was used. The Mantel-Haenszel test was used to adjust for population differences. RESULTS: Two hundred fifty-two homeless subjects and 88 controls were enrolled. Data are presented for homeless vs control patients, and all p-values were <0.01. Odds ratios (ORs) with 95% confidence intervals (95% CIs) are given where appropriate: mean age (+/-SD) = 42 +/- 10 vs 48 +/- 13; male gender 95% vs 54% (OR = 17; 95% CI = 8 to 37); history of (hx) tuberculosis 49% vs 15% (OR = 2.5; 95% CI = 1.2 to 3); hx HIV infection 35% vs 13% (OR = 3.8; 95% CI = 1.8 to 8); hx penetrating trauma 62% vs 16% (OR = 8.62; 95% CI = 4.4 to 17.1); hx depression 70% vs 15% (OR = 13.4; 95% CI = 6.7 to 27); hx schizophrenia 27% vs 7% (OR = 5.1; 95% CI = 2.0 to 14); hx alcoholism 81% vs 15% (OR = 24; 95% CI = 12 to 49); significant tooth loss (>3) 43% vs 18% (OR = 3.3; 95% CI = 1.8 to 6.4); percentage of body fat 16.5% vs 19.7%; hx social isolation (no weekly social contacts) 81% vs 11% (OR = 33.3; 95% CI = 14 to 100); mean number of ED visits/year 6.0 vs 1.6. CONCLUSIONS: In the study population homelessness was associated with a history of significantly higher rates of infectious disease, ethanol and substance use, psychiatric illness, social isolation, and rates of ED utilization.

Adult↗
PubMed2000

Filamin isogene expression during mouse myogenesis.

The developmental pattern of filamin gene expression has been studied in mouse embryos by using in situ hybridization. The probes used were isoform specific, (35)S-labeled antisense complementary ribonucleic acids (cRNAs) to the 3; untranslated region (3; UTR) of muscle-specific and nonmuscle-specific filamin genes. Northern blot and in situ hybridization results showed that nonmuscle-specific filamin transcripts had a size of 9.5 kb and were expressed in all nonmuscle tissues. Labeling was most intense in tissues containing a substantial proportion of epithelial and smooth muscle cells. Muscle-specific filamin transcripts had a size of 10 kb and were expressed primarily in cardiac and skeletal muscle. The expression of muscle-specific filamin messenger ribonucleicacids (mRNAs) was detected in heart at 8.0 days after coitum, whereas that in the myotomes of somites was not detected until 10.5 days after coitum. The expression of muscle-specific filamin mRNAs in heart and in skeletal muscle continued through the subsequent days of myogenesis. The results showed that muscle-specific filamin gene transcripts are detected before the formation of myotubes in vivo. This is the first study of filamin gene expression at the early stages of skeletal muscle development. Dev Dyn 2000;217:99-108.

Animals↗
PubMed2000

Effects of dehulled adlay on the culture count of some microbiota and their metabolism in the gastrointestinal tract of rats.

Experiments were conducted to study the effect of a dietary supplement of dehulled adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) on the culture counts of some important groups of intestinal bacteria and their metabolism in the gastrointestinal (GI) tract of Sprague-Dawley rats. Rats were divided into four groups, and each group was fed a diet containing different levels of dehulled adlay for 30 days as follows: 0% (control), 5%, 20%, and 40%. All animals fed with adlay had normal healthy intestinal walls and no pathogenic signs whatsoever. There were no significant differences in body weight gain or the cecal pH between different groups of rats. Both the 20% and 40% groups had lower culture counts of enterics in their feces than the 5% and control groups, whereas the culture counts of fecal lactic acid bacteria were higher in feces of rats fed with adlay than in the control group. Cecal total short-chain fatty acid (SCFA) content and fecal SCFA were significantly higher in the 20% and 40% groups than in the control and 5% groups. All the adlay-fed rats had a higher fecal butyric acid concentration than the control rats. It is concluded that adlay has a significant influence on the growth of intestinal bacteria, which may ultimately affect the physiology and other functions of GI tracts of rats.

Animals↗
PubMed2000

Binding of filamin isoforms to myofibrils.

Two filamin isoforms were purified from bovine tissues and characterized. Muscle filamin and nonmuscle filamin had different SDS gel mobilities, proteolytic digestion patterns, myofibrillar binding distributions and myofibril binding affinities. The muscle specific filamin had an apparent molecular weight of 265 kDa and bound primarily to the Z-lines of myofibrils but also to the I-bands near the Z-lines. The nonmuscle specific filamin had an apparent molecular weight of 275 kDa and bound exclusively to the Z-lines of myofibrils. The filamin myofibril binding was studied quantitatively. Plotting bound fraction (mg filamin/mg myofibril) vs. equilibrium concentration of free filamin yielded a biphasic binding curve. The first hyperbolic binding phase described the binding of filamin to myofibrils but the second phase appeared to be nonspecific due to filamin aggregation. The muscle filamin had a significantly lower (P < 0.05) apparent binding affinity to myofibrils than nonmuscle filamin. However, the muscle filamin showed a significantly higher (P < 0.05) saturation value for myofibrils than nonmuscle filamin. The binding of phosphorylated filamin to myofibrils was significantly lower (P < 0.05) than the corresponding native proteins for both filamin isoforms.

Animals↗
PubMed2000

Toxicology of nutmeg abuse.

BACKGROUND: Unpleasant and frightening side effects associated with the abuse of nutmeg occasionally generate emergency department referrals. We report a young patient's first-time experience with nutmeg and review the mechanisms of its toxicity. CASE REPORT: A 13-year-old female ingested 15-24 g of nutmeg over a 3-hour period and smoked and shared 2 joints of marijuana. To facilitate ingestion, the nutmeg was put into 00-000 gelatin capsules. Bizarre behavior and visual, auditory, and tactile hallucinations developed. She also experienced nausea, gagging, hot/cold sensations, and blurred vision followed by numbness, double, and "triple" vision, headache, and drowsiness. Nystagmus, muscle weakness, and ataxia were present. Her vital signs and laboratory tests were normal. She received 50 g of activated charcoal and except for complaints of dizziness and visual changes, her 2-day admission was uneventful. The central nervous system activity of nutmeg is often postulated to result from biotransformation of its chemical components to amphetamine-like compounds, but this has not been proven. Nutmeg contains several compounds with structural similarities to substances with known central nervous system neuromodulatory activity.

Adolescent↗
PubMed2000

The influence of age and gender on HLA-DR in Chinese child-onset type 1 diabetes mellitus patients.

To further clarify the association of HLA DR alleles with type 1 diabetes mellitus and the influence of age-onset and gender on type 1 diabetes, we investigated HLA-DR in 76 child onset Chinese (36 males) type 1 diabetes patients and 154 normal controls by using PCR-SSP (sequence specific primer). The mean age of onset of diabetes patients was 8.43 +/- 3.96 year-old. Our results revealed that the frequencies of DR3, DR4 and DR9 in diabetes patients were significantly higher than those in control group (all P < 0.01). The susceptible alleles were DR3, DR4, DR9, with relative risks of 8.25, 2.57 and 2.67, respectively. The protective alleles to type 1 diabetes were DR 2, DR8, DR11 and DR12 with relative risk of 0.24, 0.15, 0.16 and 0.39, respectively. There were no significant differences between the frequencies of HLA DR 3, DR4, DR9, DR3/4, DR3/9 and DR4/9 in male and female diabetic children. We divided the diabetes patients into three groups according to their age of onset (1-5 years old, 6-10 years old and 11-17 years old). There was a trend that the frequencies of DR9 decreased with the increase of age at onset, but there was no significant difference of DR3, DR4, DR9, DR3/4, DR3/9 and DR4/9 frequencies between diabetes children with age onset 0-10 years and 11-17 years. As to the influence of gender on the HLA genotypes, the frequency of DR3/4 decreased with the increase of age at onset for male patients and the frequency of DR3/4 increased with the increase of age at onset for female patients.

Adolescent↗
PubMed1999

Subthalamic nucleus lesions induce deficits as well as benefits in the hemiparkinsonian rat.

Lesions of the subthalamic nucleus can restore some imbalances in motor output of the basal ganglia induced by nigrostriatal dopamine depletion, and have been proposed as a potential therapy for Parkinson's disease. Although there is substantial supporting evidence from experimental studies in both rats and primates, there is less information on the effects of subthalamic lesions alone. In order to characterize potential side effects, the present study evaluates the behavioural effects of unilateral excitotoxic lesions of the subthalamic nucleus in rats that have previously received either unilateral saline or 6-hydroxydopamine injections into the nigrostriatal bundle on the same side. The 6-hydroxydopamine lesions induced ipsilateral orientation asymmetries in head position and body axis bias, rotational asymmetries following injections of direct or indirect dopamine agonists, neglect of contralateral stimuli, and a reduction in the numbers of pellets retrieved with the contralateral paw in a skilled reaching task. Subsequent excitotoxic lesions of the subthalamic nucleus reduced (but did not abolish) rotational asymmetries, had no effects on the measures of neglect and skilled paw-reaching, and produced contralateral orientation biases in head turning and body axis curling. Rats that received subthalamic lesions alone exhibited de novo impairments comprising contralateral biases in the orientation tests. These results support a neuromodulatory role of the subthalamic nucleus in regulating motor outputs of the basal ganglia, and caution that there may be distinct side effects of the lesion by itself. Whereas some impairments attributable to dopamine depletion may be alleviated by subthalamic manipulations, other symptoms are not, or may even be aggravated.

Animals↗
PubMed1997

The TNF2 allele does not contribute towards susceptibility to systemic lupus erythematosus.

The uncommon allele (TNF2) of a polymorphism in the promoter region of the tumor necrosis factor-alpha (TNF-alpha) gene has been reported to be increased in Caucasian systemic lupus erythematosus (SLE) patients (associated with HLA-DR3). To investigate whether TNF2 contributes towards susceptibility to Chinese SLE patients (not associated with HLA-DR3), 100 patients with SLE and 107 controls were studied. The frequency of TNF2 allele in controls was 0.140. There was a strong association between TNF2 allele and HLA-DR3 (P < 10(-8)) in controls. The frequency of TNF2 allele in SLE patients was 0.15. There was no difference in frequencies of TNF2 allele between patients and controls. This finding strongly suggests that TNF2 does not play a direct role in the susceptibility of SLE.

Alleles↗
PubMed1996

High seroprevalence of IgG against Helicobacter pylori among endoscopists in Taiwan.

A prospective survey to investigate the seroprevalence of IgG against Helicobacter pylori among endoscopists in Taiwan was conducted by analyzing blood samples of 70 study subjects and 64 nonendoscopist physicians with quantitative ELISA. Personal information and the practices of infection control related to gastroscopy examination were obtained by a self-administered questionnaire. Significant differences were detected in the IgG prevalence between study and control subjects (80.0% vs 51.6%; P < 0.05). The serum level of antibody in endoscopists (385.2 +/- 36.1 unit/ml) was significantly higher than that of nonedoscopists (211.8 +/- 33.0 unit/ml; P = 0.018). Endoscopists performing 30 or more sessions of gastroscopy per week had higher seroprevalence than those performing less than 30 sessions (90.9% vs 70.3%; P = 0.0126). In conclusion, endoscopists in Taiwan had a high prevalence of H. pylori infection. The cause might be related to the frequency of gastroscopies performed.

Adult↗
PubMed1996

[The investigation of the immunomodulatory effect of san-hwang-sei-sin-tang].

San-Hwang-Sei-Sin-Tang is a famous ancient Kampo. In order to investigate the immunomodulatory effect of this Kampo, we can stimulate lymphocytes with PHA to study the lymphocyte transformation and IL-2 production as indicators of effect. In this study, we found that the extract of San-Hwang-Sei-Sin-Tang at the concentration of 0.1 mg/ml and 1 mg/ml could effectively inhibit the index of lymphocyte transformation. San-Hwang-Sei-Sin-Tang at the concentration of 0.01 mg/ml, 0.1 mg/ml and 1 mg/ml also have the tendency of inhibition of IL-2 production. In the future, San-Hwang-Sei-Sin-Tang may be developed as an effective immunosuppressant.

Dose-Response Relationship, Drug↗
PubMed1996

Characterization of a new human transitional cell carcinoma cell line from the renal pelvis, RTCC-1/KMC.

Tumors of the renal pelvis and ureter are relatively common malignancies in Taiwan. Studying the genetic or biochemical aberrations is a feasible pursuit that has great potential to further our understanding of urothelial cancer and may provide clinically valuable information. We now report a new long-term culture (RTCC-1/KMC) of human TCC derived from the renal pelvis, which is aimed to be used as a target for those studying in this field. The cultured cells exhibited anchorage independence and loss of contact inhibition. Chromosomal analysis revealed an aneuploidy line with a modal number of 50. Population doubling time was about 36 hours at the third passage. Expression of keratin proteins confirmed its epithelial origin. The genetic markers of the RTCC -1/KMC cell line were HLA-A11, B46, B60, Cw1, Cw7, DRw12 and DRw16. The human papillomavirus and herpes simplex virus genomes were not found in this cell line.

Aged↗
PubMed1995

Chronic neutrophilic leukemia--a case report.

We describe a 77-year-old patient with chronic neutrophilic leukemia (CNL). Diagnosis of CNL was made by marked increase of mature neutrophils without increased immature granulocytes, splenomegaly and elevated serum vitamin B12 level and by ruling out any infection or occult malignancy. The chromosome analysis showed one abnormal karyotype out of 14 metaphases. The neutrophilic function with nitroblue tetrazolium test revealed impaired phagocytic function in this patient. The neutrophil count became normal gradually after hydroxyurea treatment. However, it still maintained a high percentage of mature neutrophils. Background literature and the prognosis of CNL are discussed.

Aged↗