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W L Huang

Publications and source records attributed to W L Huang.

At least 37 records · Page 2Linked to original sources
PubMed1994

Analysis of T-lymphocyte subpopulations in inflammatory bowel diseases by three-color flow cytometry.

In order to better define changes in the relative proportion of peripheral blood T-lymphocyte subpopulations in patients with inflammatory diseases of the bowel, we performed simultaneous three-color fluorescence-activated cytometric (FACS) analysis using fluorophore-conjugated monoclonal antibodies with specificity for CD4, CD8, Leu 8, and CD45RA on 22 normal control subjects, 28 patients with Crohn's disease (CD), 15 patients with ulcerative colitis (UC), and 11 patients with intestinal inflammation secondary to etiologies other than inflammatory bowel disease (NIBD). This staining combination allowed enumeration of distinct T-cell subpopulations as follows: virgin CD4+, recall antigen helper T cells, nonspecific B-cell helper T cell, virgin CD8+, cytotoxic effector and suppressor effector and recall antigen cytotoxic T cells based on a synthesis of published functional analyses. No differences in the proportion of CD4+ or CD8+ cells or in the CD4+/CD8+ ratios were evident when UC and NIBD patients were compared to normal subjects. A significant reduction in the proportion of CD4+ cells and an increase in CD8+ cells was observed, however, in the CD group. When two-color analysis was performed, several significant differences in the proportions of circulating lymphocytes were seen. Specifically, these included significant increases in the number of CD4+, Leu 8- (P < 0.01) cells in all disease groups and an increase in CD4+, CD45RA+ cells in the NIBD group. Conversely, significant decreases in the proportions of CD8+, Leu 8+ (P < 0.01) cells were evident in the Crohn's disease group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[The effects of exercise on the arterial potassium and ventilatory response under hyperoxic, normoxic, and hypoxic conditions].

BACKGROUND: Exercise leads to an increase in plasma potassium, the animal experiments showed that potassium infusion stimulated ventilation and abolished by peripheral chemodenervation and also showed that combined effects of potassium and hypoxia were greater than the sum of the individual effects. This study proposed to investigate plasma potassium and its correlation with exercise, and to investigate the effects of hypoxia and hyperoxia on potassium and ventilation during steady state exercise. METHODS: Ten male subjects exercised on a cycle ergometer. Each performed (1) incremental exercise test; (2) steady state exercise test with a work rate of about 75% of anaerobic threshold under hyperoxic (FiO2 100%), normoxic (FiO2 21%) and hypoxic (FiO2 12%) conditions, respectively. RESULTS: Arterial plasma potassium concentration rose from a pre-exercise level of 3.97 +/- 0.40 mEq/L to the post-exercise level of 5.11 +/- 0.49 mEq/L. The increase in plasma potassium during exercise correlated well with the increase in lactate (r = 0.72, p < 0.05) and the decrease in pH (r = 0.69, p < 0.05). During the steady state exercise test, switching the subject from room air to hypoxic (12% O2) conditions led to a significant rise in both plasma potassium (p < 0.05) and ventilation (p < 0.05) with good correlation between the potassium increase and the increase in ventilation (r = 0.85, p < 0.05). Switching the subject from room air to hyperoxic (100% O2) condition resulted in a significant decrease in ventilation (p < 0.05) without significant change in plasma potassium (p > 0.01). CONCLUSIONS: It was concluded that (1) exercise can lead to an increase in arterial potassium, hydrogen ion, lactate in men; (2) hypoxia can stimulate the peripheral chemoreceptor and increase plasma potassium level. Potassium may, therefore, be an important factor by which the magnitude of the peripheral chemoreflex response is augmented during exercise.

Aged↗
PubMed1994

Study on some biological and antigenic characteristics of CA24v isolates in Taiwan in 1985-1989.

In order to understand the relationship between the CA24v isolates which caused two epidemics of acute hemorrhagic conjunctivitis (AHC) in 1985-1986 and 1988-1989 in Taiwan, biological and antigenic characteristics were studied with four CA24v strains, L077/85, V116/86, 590/88 and 722/89, which were isolated during the epidemics. The prototype strain, EH24/70, was used for comparison. In terms of cross neutralization, kinetic neutralization, plaque assay and protein electrophoresis, no obvious differences were found between the isolates from the two epidemics though differences were found between these isolates and the prototype.

Conjunctivitis, Acute Hemorrhagic↗
PubMed1993

Platelet derived growth factor (PDGF), androgens and inflammation: possible etiologic factors in the development of prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) is characterized by varying degrees of epithelial and stromal hyperplasia in association with inflammation. Although androgens are known to be important for the growth and function of the prostate, their role in the development of BPH is unclear. The release of platelet-derived growth factor (PDGF) in response to inflammation suggests that PDGF may participate in the development of BPH. Cultured prostate cells derived from patients with BPH were examined for the presence of functional PDGF and androgen receptors. The cells expressed PDGF receptors and responded to PDGF stimulation by the activation of the PDGF signal transduction pathway and a dose-dependent stimulation of cell proliferation. Even though the cells expressed androgen receptors, dihydrotestosterone failed to elicit a mitogenic response. While the role of androgens in BPH remains unclear, these results suggest that inflammation and, specifically, PDGF may be important etiologic factors in the development of BPH.

Aged↗
PubMed1993

Molecular epidemiology of a variant of coxsackievirus A24 in Taiwan: two epidemics caused by phylogenetically distinct viruses from 1985 to 1989.

In order to know the phylogenetic relationship and the route of transmission of a variant of coxsackievirus A24 (CA24v), an agent that caused four sequential outbreaks of acute hemorrhagic conjunctivitis from 1985 to 1989 in Taiwan, the nucleotide sequence variations in the virus-encoded proteinase 3C region (549 nucleotides) were studied with 19 isolates. The prototype strain (EH24/70), four isolates from Japan, and two isolates from Hong Kong were used for comparison. The nucleotide sequences of the Taiwan strains from the 1985-1986 and 1988-1989 epidemics were closely related within each epidemic, while they were more distantly related between strains from two epidemics. Phylogenetic analysis by the unweighted pairwise grouping method of the arithmetic average revealed that the 19 Taiwan isolates had diverged into two groups, 1985-1986 and 1988-1989 groups. The time at which these two groups diverged was estimated to be around May 1982, more than 3 years prior to the first appearance of the CA24v epidemic in Taiwan. On each occasion, the viruses caused a 2-year epidemic and then disappeared. The Taiwan isolates from 1985 to 1986 were closely related to the Japan isolates from 1985 to 1986 and the Taiwan isolates from 1988 to 1989 were phylogenetically close to the 1989 Japan isolates, indicating that Taiwan and Japan had two common-source outbreaks. However, none of the 1988 Taiwan isolates were phylogenetically close to the 1988 Japan or Hong Kong isolates. The evidence revealed that Taiwan has had two repeated but discontinuous introductions of CA24v since its first appearance in Taiwan in 1985. None of the other CA24v strains have been detected so far.

Base Sequence↗
PubMed1993

[Polarographic determination of carbamazepine in the presence of sodium lauryl sulfate].

The electrochemical characteristics of carbamazepine (CBZ) have been studied. In a solution containing 0.40 mol.L-1 NaOH, 0.15 mol.L-1 KNO3 and 0.0020% sodium lauryl sulfate (SLS) CBZ gives a sensitive polarographic wave which can be used to determine trace amounts of the drug, the detection limit being 1.0 x 10(-6) mol.L-1. The cyclic voltammetric data show that SLS promotes adsorption of CBZ at the mercury electrode.

Carbamazepine↗
PubMed1992

Interaction of berbamine compound E6 and calmodulin-dependent myosin light chain kinase.

The interaction of the berbamine compound E6 and calmodulin (CaM)-dependent myosin light chain kinase (MLCK) has been studied. The experimental results showed that the inhibition of MLCK activity was increased with increasing amounts of E6 and was overcome completely by the addition of excessive CaM. The stimulatory activity of MLCK induced by CaM was gradually inhibited by the increasing concentrations of compound E6, showing that the inhibition of MLCK activity by compound E6 was concentration dependent; and the Ki was 0.95 microM. Compound E6 diminished the fluorescence intensity of dansyl-labeled CaM and the intensity was increased gradually by the addition of different amounts of CaM. Compound E6 had no effect on the activity of MLCK fragments produced by limited trypsinization, and it is a novel and considerably potent calmodulin antagonist.

Alkaloids↗
PubMed1992

CD5+ B cells are decreased in peripheral blood of patients with Crohn's disease.

B cells bearing the CD5 surface marker comprise a substantial minority of the circulating lymphocyte population in healthy individuals. These recently described cells have been implicated in T-independent humoral responses, immunoregulation, and autoimmunity. We undertook to enumerate circulating CD5+ B cells by three-color fluorescence activated flow cytometry in 28 patients with Crohn's disease (CD). None of the CD patients were using immunosuppressive medication. The CD patients were subdivided into "inactive" and "active" groups based upon their Crohn's disease activity index (CDAI). Thirty-two normal subjects served as a control population. The percentage of CD19+ B cells was significantly reduced in both active and inactive CD patients as compared with normal controls (P less than or equal to 0.01). CD5+ B cells were likewise found to be significantly decreased in both inactive and active CD patients (P less than or equal to 0.01) as compared with normal controls. The proportion of CD5+ B cells was significantly lower in the peripheral blood of active as compared with inactive CD patients (P less than or equal to 0.05). The finding that CD5+ B cells are reduced in CD may provide an important clue to immunological dysfunction in inflammatory bowel disease and merits further study.

Adult↗
PubMed1992

Cardiovascular effects of substituted tetrahydroisoquinolines in rats.

1. A series of substituted tetrahydroisoquinolins derived from the cleavage products of tetrandrine were found to inhibit [3H]-nitrendipine binding to rat cerebral cortical membranes. Those compounds which displaced [3H]-nitrendipine binding were also able to inhibit high KCl-induced contraction of rat aorta in vitro. 2. There was a significant correlation between the ability of these tetrahydroisoquinolines to inhibit [3H]-nitrendipine binding and KCl-induced contraction (r = 0.99, P less than 0.001). 3. CPU-23 (1-(1-[(6-methoxy)-naphth-2-yl])-propyl-2-(1-piperidine)-acetyl- 6,7- dimethoxy-1,2,3,4-tetrahydroisoquinoline), one of the most potent compounds identified in this series, behaved as a simple competitive inhibitor at the [3H]-nitrendipine binding site and reduced the apparent affinity but not the maximal number of binding sites in saturation analysis. 4. In contrast to nifedipine which caused hypotension and tachycardia, CPU-23 induced both hypotension and bradycardia in a dose-dependent manner in pentobarbitone-anaesthetized Sprague-Dawley rats, spontaneously hypertensive and age-matched normotensive WKY rats. 5. It is suggested that CPU-23 may exert its cardiovascular effects via interaction with the dihydropyridine binding site on the L-type calcium channel.

Alkaloids↗
PubMed1992

Impalpable thoracic bony lesions diagnosed by sonographically guided needle aspiration biopsy.

Impalpable osteolytic lesions may be detected and diagnosed by ultrasonography and sonographically guided needle aspiration biopsy. Eleven cases with bone destruction found on chest radiographs were proved to be malignant by sonographically guided needle aspiration biopsy. The bony lesions were all hypoechoic and could be demonstrated easily. No complications or discomfort occurred after needle aspiration. Bony lesions can be detected by ultrasonography only when pathologic changes have occurred. Ultrasonography and sonographically guided needle aspiration biopsy provide a simple, convenient, and non-invasive method for detecting and diagnosing impalpable osteolytic lesions.

Aged↗
PubMed1992

An evaluation of long-term nasal CPAP therapy for sleep apnea.

Nasal continuous positive airway pressure (CPAP) is an effective therapy for sleep apnea. Little is known about long-term patient compliance and side effects with this therapeutic modality in the Chinese. In order to evaluate this, we collected 8 obstructive sleep apnea patients who received home nasal CPAP therapy between January 1990 and July 1991. Each received two sets of nap polysomnographic studies. The initial set was performed to diagnose and evaluate patient response to CPAP as well as defining the CPAP pressure the patient would be using at home. The second set of studies were conducted for follow up and re-evaluation. Seven of these patients reported using nasal CPAP during sleep at night, and one did not use it all. Nasal CPAP improved clinical symptoms, particularly daytime sleepiness, and 7 patients were generally satisfied with nasal CPAP. Initially the side effects were a dry throat and nose. After 5 to 15 months of CPAP treatment, the follow-up nap sleep studies showed no significant change in the apnea/hypopnea index, duration of apnea, or oxygen desaturation between the diagnostic and follow-up (without CPAP) studies. However the amount of nasal CPAP pressure setting declined in 4 of 7 patients. Our own experience indicates that long-term nasal CPAP is an important new means of treatment for sleep apnea and allows a normal daytime life. It was well-tolerated by most sleep apnea patients. However, it is necessary to further evaluate of morbidity and the amount of pressure setting relative to long-term home nasal CPAP.

Adult↗
PubMed1992

[Blood lactate changes during incremental exercise in chronic obstructive pulmonary disease].

In order to evaluate whether the lactic acidosis is developed during incremental exercise test in COPD. 12 untrained subjects with COPD performed incremental maximal cycle ergometer tests. Ventilation (VE); O2 uptake (VO2), CO2 output (VCO2); and end-tidal CO2 fraction (FETCO2) were measured. Arterial lactate concentration and blood gas analysis were measured at rest, maximal exercise and recovery of exercise from an indwelling arterial catheter. of the degree of airway obstruction. (2) T40 and BEecf correlated well with lactate change (r = 0.83; 0.84, P < 0.05). (3) The change of VE, and RQ correlated with the lactate change (r = 0.81; 0.83, 0.72, P < 0.05), but not the VE/VO2, VE/VCO2, nor FETCO2, (r = 0.24; 0.06; 0.46, P > 0.05). We concluded that the blood lactate increased markedly in patients of COPD during increment exercise, and it was well corrected with the change of VE, VCO2 and RQ. The increased lactate could be indicated by the concomitant change of T40 and BEecf.

Aged↗
PubMed1992

Detection of mass lesions in the collapsed lung by ultrasonography.

Ultrasonography is useful in the detection of mass lesions in the collapsed lung, using the collapsed lungs as a "sonic window". Twenty-four patients suspected of having a tumor causing lung collapse, as shown on their chest radiographs, were examined by ultrasonography. Eighteen out of 24 patients were found to have mass lesions in their collapsed lungs. Thoracic computed tomography (CT) was also performed in 12 of these 18 patients; of those, 11 showed compatibility with sonographic findings in the detection of mass lesions in their collapsed lungs. The remaining six of these 24 patients with no mass lesions detected by ultrasonography were proven to have collapsed lung due to sputum impaction (n = 2) and lung cancer (n = 4). The fact that four patients had lung cancer that was not detectable by ultrasonography, might have been due to relatively small mass lesions at deep locations (main or intermediate bronchus) and narrowing of the "sonic window" (partial lung collapse). Though it has some limitations, ultrasonography is helpful in detecting mass lesions in collapsed lungs. Sono-guided fine needle aspiration biopsy (SGFNAB) can also be performed simultaneously, smoothly and without any major complications. In our series, SGFNAB was performed in eight out of 18 patients to make a cytopathologic diagnosis. We recommend this safe, convenient, and noninvasive method to screen for lesions in the collapsed lung, especially when bronchoscopic examination is impossible.

Aged↗
PubMed1991

A new device of incentive spirometry.

Incentive spirometry is a feedback system to encourage patients to take a deep breath and produce a sustained maximal inspiration (SMI) for the primary purpose of opening and stabilizing atelectatic areas of the lung. However, currently available incentive devices are not reusable, expensive, and emphasize inspiratory effort only. We have designed a new device of incentive spirometer based on pursed-lip breathing technique. The device consists of a piece of paper hanging on a frame. The patient is instructed to take a deep and slow inspiration followed by holding the breath for 5 seconds. Then, using pursed-lip technique, the patient generates a flow to keep the paper attached to a bar as long as possible. The duration of paper blowing is recorded and is compared with vital capacity. In the present study 96 cases were recorded. Vital capacity was correlated well with paper blowing time (multiple regression test r = 0.87, p less than 0.0001). The advantages of our device include (1) reusibility and less cost, (2) equal emphasis of both inspiration and expiration, and (3) being especially helpful for patients with chronic obstructive lung disease (COPD). This is a preliminary result and further clinical study is needed.

Breathing Exercises↗
PubMed1991

Anti-arrhythmic activities of six indole derivatives of changrolin.

The indole-derived compounds, which possessed side chains resembling those of changrolin (4-[3',5'-bis[(N-pyrrolidinyl)methyl]-4'-hydroxyaniline]-quinazoline) showed potent anti-arrhythmic activity by restoration of sinus rhythm from ouabain-induced tachycardia in guinea pigs. The potency was assessed by comparison of the maintenance time of sinus rhythm recovered from tachyarrhythmias induced by ouabain. The promising compound was MI2 with piperidyl residue on position 3 & 5 of phenol moiety. There was no difference in anti-arrhythmic activities resulting from substitutions between a benzene ring and methyl residue at position 2 of indole, but the latter had weaker parasympatholytic activity. The anti-arrhythmic activity of MI2 (greater than 60 min) was 2.4 times more potent then changrolin (25 min), but its anti-cholinergic activity was only half of the latter. To compare the suppressive effect on reperfusion-induced arrhythmias by iv MI2 at different time in relation to the ligation-reperfusion protocol, it was the most effective when administered either 30 min prior to coronary occlusion or at the moment of reperfusion. The compound MI might belong to the Ic group shown by the slowing impulse conduction within the heart.

Animals↗