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Y H Hsieh

Publications and source records attributed to Y H Hsieh.

35 records · Page 2Linked to original sources
PubMed1998

Development of a monoclonal antibody specific to cooked mammalian meats.

Detection of species adulteration in ground meat products is important for consumer protection and food-labeling law enforcement. This study was conducted to develop monoclonal antibodies (MAbs) that can be used in an enzyme-linked immunosorbent assay (ELISA) for rapid detection of any cooked mammalian meats in cooked poultry products. Soluble muscle proteins extracted from cooked pork (heated at 100 degrees C for 15 min) were used as the antigen to immunized mice for developing the MAb. One that was developed, MAb 2F8 (IgG2b class), strongly reacted with cooked meat of five mammalian species (beef cattle, hogs, sheep, horse, and deer) but did not react with any cooked poultry (chicken, turkey, and duck) or raw meats. At least 0.5% by weight of pork, beef, lamb, and horse meats in a chicken-based mixture could not detect using the indirect ELISA with MAb 2F8. The MAb 2F8 is useful in a single initial screening test to detect the presence of five nonpoultry meat adulterants in cooked poultry products.

Animals↗
PubMed1998

Recurrent spontaneous bacterial empyema in cirrhosis: a case report.

Spontaneous bacterial empyema occurs in about 0.4% of cirrhotic patients, but recurrent attack has rarely been reported. Herein we report a case of repeat episodes of spontaneous bacterial empyema. The patient presented with fever, shortness of breath and three episodes of spontaneous bacterial empyema (accompanied by septic shock in two episodes) within six months. Chest roentgenography showed massive right-side pleural effusion. Thoracentesis yielded pleural effusion containing a neutrophil count of more than 500/microliter. A blood culture grew non-O1 Vibrio cholerae in one episode and the pleural effusion culture grew Aeromonas hydrophila. A chest-tube was inserted during the latest episode due to a low pH and glucose concentration in the pleural fluid. The patient recovered well after medical treatment. The etiology, diagnosis and management of spontaneous bacterial empyema are discussed.

4-Quinolones↗
PubMed1997

Severe disease in children with trachoma is associated with persistent Chlamydia trachomatis infection.

The immediate study objective was to determine if variable disease severity in children with trachoma could be attributable in part to host variation in the ability to clear Chlamydia trachomatis infection. Identification of sibling cohorts with these variant phenotypes would be useful for immunogenetic studies. A weekly survey for 3 months in a trachoma-hyperendemic village using detection of chlamydial DNA and grading of disease severity indicated that 62% (33/53) of children had at least one infection episode. Of those, 64% (21/33) who were persistently infected had both significantly higher mean chlamydial DNA loads and more severe trachoma than did sporadically infected children. Of importance, duration of infection differed between siblings in 60% (6/10) of families. The results suggest that chlamydial load and duration of infection determine the chronic nature of severe disease in trachoma and that host variable efficiency for chlamydial clearance between siblings is in part determined by host variation.

Adenoviruses, Human↗
PubMed1997

Esophageal reflux after total or proximal gastrectomy in patients with adenocarcinoma of the gastric cardia.

OBJECTIVES: To demonstrate gastroesophageal reflux induced by proximal gastrectomy and to report preventive measures, such as total gastrectomy followed by Roux-en-Y esophagojejunostomy. METHODS: Thirteen patients underwent proximal gastrectomy (PG), and six patients underwent total gastrectomy (TG). Two of the 13 patients who received PG later underwent completion total gastrectomy. All patients were followed with endoscopy, radionuclide scintigraphy, and 24-h pH monitoring. RESULTS: Endoscopic examination revealed evidence of esophagitis in all PG group patients; however, none of the TG group had esophagitis. Prolonged esophageal transit was observed in 11 patients (10 in the PG group, one in the TG group). Increased residual fraction was found in 10 patients (nine in the PG group, one in the TG group). An increase in the retrograde index was found in 14 cases (11 in the PG group, three in the TG group). Positive enterogastroesophageal reflux was identified in 11 patients (eight in the PG group, three in the TG group). Twenty-four hour pH monitoring resulted in 10 positives (10 in the PG group, none in the TG group). CONCLUSIONS: Frequently, proximal gastrectomy will lead to significant gastroesophageal reflux and, subsequently, to varying degrees of esophagitis. The clinical symptoms are usually characteristic. However, the severity of esophagitis and the mechanism of reflux can be determined only by integrated interpretation of a reflux study. The study should include endoscopy, radionuclide scintigraphy, and 24-h pH monitoring. Although a total gastrectomy with Roux-en-Y diversion can reduce the incidence of acid reflux, neutral enteroesophageal reflux may be observed during a radioactive isotope study. Fortunately, neutral refluxes rarely cause esophagitis. A proximal gastrectomy should be avoided in adenocarcinoma of the gastric cardia, except in early cancer. Symptomatic palliation can be relieved by medication. However, completion total gastrectomy is the only effective method for eradicating unrelenting symptoms.

Adenocarcinoma↗
PubMed1996

A two-sex model for treatment of HIV/AIDS and behaviour change in a population of varying size.

In this work, we propose a model for heterosexual transmission of HIV/AIDS incorporating a community-wide screening and treatment programme. We will investigate various consistency assumptions about the conservation of heterosexual contacts, which will enable us to reduce this two-sex model to a simpler one-sex formulation. In all cases analytical results will be given with threshold parameters obtained for the persistence of disease, the persistence of total populations, and the persistence of infective populations. By comparing the theoretical results for the different variations of our model, we hope to shed some light on the effectiveness of the prevention and control measures that are needed to deal with the emerging AIDS epidemic in Third World communities with growing populations.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Community treatment of HIV-1: initial stage and asymptotic dynamics.

Treatment with antiviral drugs (zidovudine and ddI) has been reported to delay progression to AIDS, and may even possibly lower the infectiousness of the infectives. However, its effect on the community level is still uncertain. The latter is important since a successful community treatment program must meet both public health and individual health goals. Our study will focus on the effect of a community-wide treatment program initiated at the early stages of the disease as well as the long-term effect of the program. Using a simple mathematical model, we demonstrate that a community-wide treatment program could be instrumental in decreasing HIV incidence rate and eradicating the disease in the future if certain conditions on the parameters are met. On the other hand, when the above mentioned conditions on the parameters are not satisfied, we show that even if the treatment does improve survival in AIDS patients and decrease the rate at which HIV infection spreads in the community, it is still possible for the treatment program to have an adverse effect on the spread of AIDS in the population in the long run. Hence, a public health policy maker must exercise caution in order to design an effective treatment program for HIV/AIDS.

Community Health Services↗
PubMed1994

Modelling the effect of treatment and behavioral change in HIV transmission dynamics.

In this paper we analyze a model for the HIV-infection transmission in a male homosexual population. In the model we consider two types of infected individuals. Those that are infected but do not know their serological status and/or are not under any sort of clinical/therapeutical treatment, and those who are. The two groups of infectives differ in their incubation time, contact rate with susceptible individuals, and probability of disease transmission. The aim of this article is to study the roles played by detection and changes in sexual behavior in the incidence and prevalence of HIV. The analytical results show that there exists a unique endemic equilibrium which is globally asymptotically stable under a range of parameter values whenever a detection/treatment rate and an indirect measure of the level of infection risk are sufficiently large. However, any level of detection/treatment rate coupled with a decrease of the transmission probability lowers the incidence rate and prevalence level in the population. In general, only significant reductions in the transmission probability (achieved through, for example, the adoption of safe sexual practices) can contain effectively the spread of the disease.

HIV Infections↗
PubMed1979

Theory of the dependence of population levels on environmental history for semelparous species with short reproductive seasons.

A population that is strongly self-regulating through density-dependent effects is expected to be such that, if many generations have elapsed since its establishment, its present size should not be sensitive to its initial size but should instead be determined by the history of the variables that describe the influence of the environment on fecundity, mortality, and dispersal. Here we discuss the dependence of abundance on environmental history for a semelparous population in which reproduction is synchronous. It is assumed that at each instant t: (i) the rate of loss of members of age a by mortality and dispersal is given by a function rho of t, a, and the present number x = x(a,t) of such members; and (ii) the number x(0,t) of members born in the population is given by a function F of t and the number of x(a(f),t) at a specified age a(f) of fecundity. It is further assumed that the functions rho and F have the forms rho(x,a,t) = pi(1)(a,t)x + pi(2)(a,t)x(2) and F(x(a(f),t),t) = nu(t)x(a(f),t). For such a population, a change in the environment is significant only if it results in a change in nu(t) pi(1)(a,t), or pi(2)(a,t), and, hence, the history of the environment up to time t is described by giving nu(tau), pi(1)(a,tau), and pi(2)(a,tau) for each tau </= t and all a in [0, a(f)]. We show that the dependence of x on the history of the environment can be calculated explicitly and has certain properties of "fading memory"; i.e., environmental events that occurred in the remote past have less effect upon the present abundance than comparable events in the recent past.

Animals↗
PubMedDate not supplied

A model for HIV in Asia.

A model is proposed in which the spread of HIV/AIDS in the community is mainly due to the sexual interaction between a core group of female prostitutes and young unmarried males. Several threshold parameters are obtained that determine persistence of endemic proportions, persistence of total population, and the persistence of infective population given the extinction of endemic proportions in a population tending to infinity. Conditions are given for the existence of multiple endemic equilibria as well as the existence of multiple stable equilibria with separatrix and their asymptotic behavior and biological significance are discussed. In all cases, global analysis is accompanied by bifurcation diagrams, and numerical examples are provided for some particular cases of interest. This model was proposed with the recent rapid growth of the HIV/AIDS epidemic in Asia in mind.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Detection of pork in heat-processed meat products by monoclonal antibody-based ELISA.

An enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody to a porcine thermal-stable muscle protein was developed for detection of pork in cooked meat products. The assay specifically detects porcine skeletal muscle, but not cardiac muscle, smooth muscle, blood, and nonmuscle organs. No cross-reactivity was observed with common food proteins. Validity of the assay was evaluated with laboratory formulated and commercial meat samples. The detection limit was determined as 0.5% (w/w) pork in heterologous meat mixtures. Overall, intra- and inter-assay coefficients of variation were 5.8 and 7.9%, respectively. The accuracy in analyzing market samples was 100% as verified by product labeling and confirmed by a commercial polycolonal antibody test kit.

Animals↗
PubMedDate not supplied

Determination of carbon dioxide evolution rates using a novel noninstrumental microrespirometer.

A novel noninstrumental microrespirometer was developed to determine carbon dioxide evolution rates of solid or liquid samples at microL/h levels accurately and rapidly. The respirometer is based on the simple principle of acid-base titration at a steady-state of carbon dioxide absorption/evolution. The structure and operation of the microrespirometer are simple and the cost is modest in comparison to instrumental methods. The microrespirometer is suitable for laboratory studies and field routine examinations of food, agricultural, and environmental samples.

Absorption↗
PubMedDate not supplied

A 3-day anti-Helicobacter pylori therapy is a good alternative for bleeding peptic ulcer patients with Helicobacter pylori infection.

BACKGROUND/AIMS: One-week triple therapy has been recommended as a standard regimen for eradicating Helicobacter pylori infection. The emergence of antibiotic-resistant strains, adverse drug effects, poor compliance and high cost of therapy add problems to the management of these patients. In this study, we assessed whether a 3-day triple therapy could be effective in eradicating Helicobacter pylori infection in bleeding peptic ulcer patients. METHODOLOGY: Peptic ulcer patients with Helicobacter pylori infection were enrolled in this study. Patients enrolled at the outpatient department (group A) received a 7-day oral regimen: bismuth subcitrate colloid 300 mg + amoxicillin 500 mg + metronidazole 250 mg four times per day. Patients who were admitted to the wards due to peptic ulcer bleeding (group B) received a 3-day regimen including omeprazole 40 mg intravenously every 6 hours, amoxicillin 500 mg + metronidazole 250 mg orally four times daily after hemostasis had been achieved. Patients of both groups received omeprazole 20 mg once per day or cimetidine 400 mg twice daily per os for at least-one month after anti-Helicobacter pylori therapy. We followed every patient endoscopically two months after anti-Helicobacter pylori therapy. RESULTS: From June 1997 to April 1999, a total of 57 patients (30 in group A and 27 in group B) with gastric or duodenal ulcer and Helicobacter pylori infection completed anti-Helicobacter pylori therapy. Two months after anti-Helicobacter pylori therapy, peptic ulcer was found to be healed with a scar in 26 (86.7%) of group A and 23 (85.2%) of group B (P > 0.1). The eradication rates of Helicobacter pylori in the two groups were not significantly different in an intention-to-treat analysis [group A: 78.8% (26/33), 95% CI: 64.9-92.7%; group B: 80% (24/30), 95% CI: 65.7-94.3%, P > 0.1] and in a per protocol analysis [group A: 86.7% (26/30), 95% CI: 74.5-98.9%, group B: 88.9% (24/27), 95% CI: 77.1-100.7%, P > 0.1]. Fewer side effects occurred in group B (3/30) than those in group A (7/33) (P > 0.1). CONCLUSIONS: In patients with peptic ulcer bleeding a 3-day anti-Helicobacter pylori therapy is a good alternative for eradicating Helicobacter pylori infection.

Adult↗
PubMedDate not supplied

Is submucosal epinephrine injection necessary before polypectomy? A prospective, comparative study.

BACKGROUND/AIMS: Polyps of the gastrointestinal tract are usually removed due to their link to bleeding, obstruction and malignancy. However, complications may occur following polypectomy. The aim of this study was to assess whether submucosal epinephrine injection before polypectomy could reduce the incidence of bleeding and perforation. METHODOLOGY: Between June 1997 and November 1999, patients with sessile polyps of the gastrointestinal tract found in our endoscopic unit were randomized to receive submucosal epinephrine injection (epinephrine group) or no injection (control group) before polypectomy. In the epinephrine group, epinephrine (1:10,000) was injected surrounding the stalk of the polyp until the mucosa was blanched and bulged. The patients were observed for complications in the following month. RESULTS: A total of 120 patients with 151 sessile polyps were enrolled in this study. In the epinephrine group, 75 polyps (n = 68) were randomized to receive epinephrine injection before polypectomy. In the control group, 76 polyps (n = 61) underwent polypectomy without epinephrine injection. In both groups, there was no significant difference in clinical features including the sizes of the polyps and their stalks, the location of polyps and the pathological diagnosis. There were a total of nine episodes of post-polypectomy hemorrhage, two in the epinephrine group and seven in the control group (2/75 vs. 7/76) (P = 0.07). One case in the epinephrine group experienced delayed bleeding (4 days later). Immediate hemorrhage occurred less in the epinephrine group than that in the control group (1/75 vs. 7/76, P = 0.03). There was one case of perforation in each group. CONCLUSIONS: Epinephrine injection prior to polypectomy is effective in preventing immediate bleeding.

Adult↗