Biomedical subjects

W C Hsieh

Publications and source records attributed to W C Hsieh.

At least 73 records · Page 4Linked to original sources

PubMed1992

In vitro antibacterial activities of ticarcillin alone and ticarcillin plus clavulanic acid against beta-lactamase producing and non-producing microorganisms.

A total of 818 clinical bacterial isolates were tested for the production of beta-lactamase by rapid chromogenic cephalosporin method and for the susceptibility to ticarcillin alone and in combination with clavulanic acid (2 micrograms/mL) by agar dilution method. These included 83 strains of methicillin-sensitive Staphylococcus aureus (MSSA), 31 of methicillin-resistant S. aureus (MRSA), 49 of Neisseria gonorrhoeae, 58 of Haemophilus influenzae, 112 of Escherichia coli, 118 of Klebsiella pneumoniae, 58 of Proteus mirabilis, 30 of Proteus vulgaris, 60 of Serratia marcescens, 113 of Enterobacter cloacae, 60 of Pseudomonas aeruginosa and 46 of Bacteroides fragilis. The results revealed that 46.6% of P. mirabilis, 53.4% of H. influenzae, 57.1% of N. gonorrhoeae, 80% of P. vulgaris, 83.9% of MRSA, 85.6% of MSSA, 87.5% of E. coli, 91.7% of S. marcescens, 95.7% of B. fragilis, 98.2% of E. cloacae, and 100% of K. pneumoniae and P. aeruginosa strains produced beta-lactamase. In general, beta-lactamase nonproducers were more susceptible to ticarcillin than beta-lactamase producers. The ranges of minimum inhibitory concentrations (MICs) of ticarcillin for beta-lactamase nonproducers of MSSA, MRSA, H. influenzae, E. coli, P. vulgaris, S. marcescens, E. cloacae, B. fragilis and beta-lactamase producers of MSSA, H. influenzae strains were all within the in vitro susceptible range. The presence of clavulanic acid resulted in a significant enhancement of the antibacterial activity of ticarcillin against beta-lactamase producers of MRSA, N. gonorrhoeae, E. coli, K. pneumoniae, P. mirabilis, P. vulgaris and B. fragilis strains. Clavulanic acid had no synergistic activity for ticarcillin against S. marcescens, P. aeruginosa and E. cloacae.

Bacteria↗

PubMed1992

Streptococcus bovis endocarditis associated with colonic adenocarcinoma: report of a case.

Streptococcus bovis (S. bovis) endocarditis has been increasing over recent decades, especially among the senile population. A 74-year-old man presented with intermittent fever for two months. He had a past history of aortic dissection and underwent a Bentall operation one year before admission. A Janeway lesion was noted on his right hand and six blood cultures grew S. bovis. He was treated with penicillin-G, 3 microU intravenously, every six hours, and became afebrile three days later. A colonofiberoscopy was carried out despite the absence of any gastrointestinal symptoms, and a 2 x 2 cm mass was found at the cecum, with pathologic proof of adenocarcinoma. The patient died from a massive intracranial hemorrhage on the 23rd hospital day. Review of the literature revealed an intimate association between S. bovis bacteremia (or endocarditis) and underlying colonic neoplasia. Failure to be aware of the possible consequences of this combination may lead to detrimental patient prognosis. We strongly advise that every patient presenting with bacteremia or endocarditis due to this organism, even if they are free from gastrointestinal symptoms, should undergo a thorough lower gastrointestinal investigation to rule out colonic neoplasia.

Adenocarcinoma↗

PubMed1992

Epidemiologic investigation of nosocomial outbreak of methicillin-resistant Staphylococcus aureus by plasmid pattern analysis.

Nosocomial infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have become an important problem with increasing frequency. In order to learn if plasmid pattern analysis can be used in epidemiologic investigations of MRSA infections, the authors did plasmid extractions of 70 MRSA stock isolates using a rapid lysostaphin lysis method. All isolates carried at least one plasmid. Most of the isolates had one large plasmid of 24-28 megadaltons (Md). Many also carried one or two small plasmids. Accordingly, 12 different patterns were identified. From these background results, we applied this method to the investigation of two small nosocomial outbreaks of MRSA infection. It was found that the analysis of plasmid pattern and restriction endonuclease analysis are more discriminative than antibiograms. Strains with the same antibiograms can be different by plasmid analysis. It is concluded that the plasmid pattern with a restriction endonuclease analysis study is a reliable method for epidemiologic study of MRSA infections.

Cross Infection↗

PubMed1992

Effect of food on pharmacokinetics of cefuroxime axetil in Chinese subjects.

The effect of food on the pharmacokinetics of cefuroxime axetil was studied. Twelve healthy male subjects were included in this study. They were given single oral 500 mg doses of cefuroxime axetil alone or with food based on a balanced two-way crossover design. Plasma cefuroxime concentrations were assayed by the high performance liquid chromatographic method. When the drug was given alone, the area under the curve (AUC) was 15.77 +/- 4.12 mg*h/L, Cmax was 4.20 +/- 1.05 mg/L, Tmax was 2.36 +/- 0.84 h, T1/2 was 1.56 +/- 0.26 h, and Clp/F was 34.13 +/- 10.39 L/h; 45.12 +/- 9.59% of the dose was recovered in the urine within 24 hours, and the renal clearance was 12.58 +/- 4.41 L/h. When the drug was given with food, the corresponding AUC was 23.46 +/- 4.57 mg*h/L, Cmax was 7.10 +/- 1.41 mg/L, Tmax was 2.04 +/- 1.32 h, T1/2 was 1.40 +/- 0.23 h, and Clp/F was 21.93 +/- 5.18 L/h; the 24-hour urinary recovery was 69.33 +/- 6.13% and the renal clearance was 12.58 +/- 2.99 L/h. The above pharmacokinetic parameters obtained from the two regimens were compared by two-way ANOVA corrected for the change-over effect. No significant difference was found for Tmax, T1/2 or renal clearance (p > 0.05). Higher AUC, Cmax, urinary recovery and lower Clp/F values were observed for the regimen with food (p < 0.05). The plasma drug concentrations resulting from the regimen with food were higher throughout the 12-hour sampling period when compared to the regimen without food.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Status and trend of HIV-1 infection and AIDS in Taiwan, December, 1991.

From May 1, 1985 to December 31, 1991, a total of 4,962,707 serum samples from 8 population groups in Taiwan were tested for anti-human immunodeficiency virus type 1 (anti-HIV-1). In total, 256 samples were seropositive; of these individuals, 43 developed acquired immunodeficiency syndrome (AIDS): 29 were homosexuals; 5 were hemophiliacs; 8 were heterosexuals and 1 was of unknown risk. Although the prevalence of HIV-1 infection and AIDS remains low compared with other countries, since 1988 the increase has been rapid. Before 1977 the majority were homosexuals and hemophiliacs; thereafter the risk groups diversified, with a trend away from homosexuals and hemophiliacs towards heterosexuals and intravenous drug abusers (IVDAs). A few patients have caused serious social problems for the public, health care workers and families. Active community efforts are needed to achieve future success in the control of HIV-1 infection and AIDS in Taiwan.

Acquired Immunodeficiency Syndrome↗

PubMed1992

[Identification and typing of Pseudomonas pickettii during an episode of nosocomial outbreak].

From January to April 1989, Pseudomonas pickettii was isolated from clinical specimens of 24 hospitalized patients at the National Taiwan University Hospital in Taipei. The source of the organism was the 0.9% NaCl solution prepared by the hospital pharmacy. A total of 39 isolates of P. pickettii were collected, including 28 from clinical specimens and 11 from 0.9% saline and distilled water during the outbreak. These microorganisms were studied by using four methods, namely, conventional biochemical method, Vitek Auto-Microbic System (Vitek AMS), gas-liquid chromatographic analysis of cellular fatty acids composition and determination of the minimum inhibitory concentrations of 10 different antimicrobial agents. By conventional biochemical method, 16 isolates were typed as biovar 1 and 23 strains were biovar 3. Strains of both biovars were recovered from clinical specimens and 0.9% saline. Vitek AMS was able to identify P. pickettii correctly, but the result of biotyping was not satisfactory. Analysis of cellular fatty acids could rapidly identify P. pickettii to the species level, but could not distinguish the different biovars. By determination of the MICs, the antibiogram could be classified into 9 patterns. Of 16 isolates of P. pickettii biovar 1, 7 (44%) belonged to pattern I, and 9 (56%) pattern II. Strains of both patterns were found in cultures of clinical specimens and 0.9% saline. Of 23 isolates of P. pickettii biovar 3, 11 (48%) belonged to pattern III, 4 (17%) pattern IV and 8 (35%) pattern V to IX. Pattern III and pattern IV were seen in isolates from clinical specimens and 0.9% saline, while pattern V to IX were only seen in isolates from clinical specimens.(ABSTRACT TRUNCATED AT 250 WORDS)

Cross Infection↗

PubMed1991

In vitro activities of 36 antimicrobial agents against clinically isolated Bacteroides fragilis.

Thirty-six antimicrobial agents were evaluated for in vitro activities against 100 clinical isolates of Bacteroides fragilis. The minimal inhibitory concentration (MIC) of each agent for each isolate was determined by the agar dilution method. Among 25 beta-lactam antibiotics, the most active agent was imipenem with an MIC90 and a geometric mean of 1 and 0.15 micrograms/ml, respectively; followed by ticarcillin-clavulanic acid, and amoxicillin-clavulanic acid. Ampicillin-sulbactam, piperacillin-tazobactam, moxalactam, and flomoxef were the next most active agents. Piperacillin, ticarcillin, ceftizoxime, cefotaxime, cefuzonam, cefoxitin, and cefmetazole were equally active with the MIC50s ranging from 4 to 16 micrograms/ml, and MIC90s ranging from 32 to greater than or equal to 256 micrograms/ml. The remaining 10 beta-lactam antibiotics, ampicillin, amoxicillin, cefazolin, cefuroxime, cefoperazone, cefmenoxime, ceftazidime, cefpirome, aztreonam, and carumonam were less active. All isolates were resistant to cefotiam at a low breakpoint. Among 6 quinolones, ciprofloxacin was the most active agent with an MIC50 and an MIC90 of 4 and 16 micrograms/ml, respectively. All isolates were resistant to nalidixic acid, pipemidic acid, cinoxacin, enoxacin, and norfloxacin. Among 5 frequently used agents, chloramphenicol, ornidazole, and metronidazole were the most effective agents which inhibited 100% of the isolates at 8, 2, and 2 micrograms/ml, respectively; while clindamycin and minocycline had less activity.

4-Quinolones↗

PubMed1991

Antimicrobial activities of piperacillin alone and in combination with tazobactam against beta-lactamase-producing bacteria.

Tazobactam (YTR 830), a new beta-lactamase inhibitor, was evaluated for its effect in combination with piperacillin, a broad spectrum, but beta-lactamase sensitive, penicillin, against 14 common bacteria. A total of 1,086 clinical isolates from different clinical specimens were tested for beta-lactamase production by the rapid chromogenic cephalosporin method. Their susceptibilities to piperacillin alone and in combination with tazobactam in a ratio of 8:1 by the agar dilution method were evaluated. The percentage of beta-lactamase producing strains ranged from 14.5% to 100% in these tested species. In general, the beta-lactamase producers were more resistant to piperacillin than the beta-lactamase nonproducers with higher minimal inhibitory concentrations (MICs). For the beta-lactamase producers, tazobactam decreased the MICs of piperacillin prominently in methicillin-resistant Staphylococcus aureus, Neisseria gonorrhoeae, Haemophilus influenzae, Escherichia coli, Proteus mirabilis, Morganella morganii, Salmonella species and Bacteroides fragilis, with a 4-fold or greater decrease in MIC50, MIC90 and the geometric mean of MIC. For Serratia marcescens and Pseudomonas aeruginosa, the MICs did not change after adding tazobactam. For other species, there was a moderate decrease in MICs. We conclude that tazobactam is an effective beta-lactamase inhibitor for increasing the antimicrobial activity of piperacillin against beta-lactamase producing strains of many species of bacteria.

Ampicillin Resistance↗

PubMed1991

Acinetobacter calcoaceticus bacteremia: analysis of 48 cases.

The medical records of 48 patients with Acinetobacter calcoaceticus bacteremia over a recent two-year period were reviewed retrospectively to determine the epidemiologic and clinical features. There were 34 males and 14 females with a median age of 51 years. Forty-six of the cases were hospital-acquired. The characteristics of these patients included residence in the intensive care unit, intubation and ventilatory support, preceding antibiotic therapy and intravascular catheterization. In vitro susceptibility testing for the isolated organisms revealed that 32% of these strains were resistant to gentamicin and 90% were aztreonam-resistant. Minocycline, amikacin, ceftazidime, ticarcillin, imipenem, and the new quinolones retained good activity. Although A. calcoaceticus causes septic pictures as do other aerobic Gram-negative bacilli and part of these isolates are multiple drug-resistant, the infection did not seem to be difficult to control. Twenty-six (54%) of these patients survived, including 9 patients without appropriate antimicrobial therapy initiated within 48 hours of blood sampling. The mortality was rarely due to bacteremia per se; most often, it resulted from the underlying diseases.

Acinetobacter Infections↗

PubMed1991

Actinobacillus actinomycetemcomitans endocarditis: a report of four cases and review of the literature.

Four patients with infective endocarditis caused by Actinobacillus actinomycetemcomitans seen at the National Taiwan University Hospital between January 1985 and December 1990 are reported. There were two men and two women with a mean age of 40 years. Three had had a xenograft replacement, the other one had prolapse of mitral valve. Carious teeth were noted in two. The most common presenting symptoms were fever, cough, dyspnoea, and weight loss and the duration of symptoms before diagnosis varied from 2 weeks to 2 months. Peripheral stigmata of endocarditis were not present in any patient. Laboratory investigation revealed haematuria and anaemia in three patients, and elevated erythrocyte sedimentation rates in all four. None had leucocytosis. Echocardiography was performed more than once for each patient and vegetation was demonstrated in only one. Blood culture became positive after 7-10 days of incubation. One of the isolates was resistant to penicillin. The diagnosis was delayed due to the indolent clinical course, non-specific presentation, and the slow growth of the organism. However, all patients were cured clinically and bacteriologically after 6 weeks of intravenous antibiotic therapy which included penicillin, cefamandole, chloramphenicol, or aztreonam, with or without an aminoglycoside. All patients were free of evidence of recurrence after 6-25 months of follow-up.

Actinobacillus Infections↗

PubMed1991

Antibacterial activities of amoxicillin alone and in combination with clavulanic acid correlated with beta-lactamase production.

Amoxicillin, a beta-lactam antibiotic, was tested for its effect in combination with clavulanic acid, a beta-lactamase inhibitor, against 9 species of bacteria isolated from clinical specimens. A total of 698 strains of bacteria were tested for beta-lactamase production by the rapid chromogenic cephalosporin method. Their susceptibilities to amoxicillin alone and in combination with clavulanic acid were tested by the agar dilution method. The percentage of beta-lactamase producing strains ranged from 46.6% in Proteus mirabilis to 100% in Klebsiella pneumoniac. In general, beta-lactamase nonproducers were more susceptible to amoxicillin than beta-lactamase producers. For beta-lactamase producers, clavulanic acid decreased the MICs of amoxicillin prominently in strains of Neisseria gonorrhoeae, Haemophilus influenzae, Escherichia coli, K. pneumoniae, P. mirabilis, Enterobacter cloacae and Bacteroides fragilis, when combining clavulanic acid with amoxicillin in the ratio of 1:2. Their MIC50s, MIC90s and geometric means of MICs all decreased 4 folds or greater. For beta-lactamase non-producing strains, the MICs did not show significant differences by adding clavulanic acid in most species we tested, including methicillin-sensitive Staphylococcus aureus, N. gonorrhoeae, H. influenzae, Proteus vulgaris and E. cloacae.

Amoxicillin↗

PubMed1991

Diagnostic value of measuring BCG sonicate antigen and anti-BCG antibodies in the cerebrospinal fluid and blood of patients with tuberculous meningitis.

Fourteen cerebrospinal fluid (CSF) and paired blood samples were obtained from patients with tuberculous meningitis, seven with positive culture and seven clinical/laboratory diagnosis. Another 14 paired specimens served as control, including 7 infectious meningitis and 7 non-inflammatory neurological diseases. Four groups were thus classified, including confirmed and suspected patients, and controls with infectious meningitis and neurological diseases. Measurements of Bacillus Calmette-Guérin (BCG) sonicate antigen and IgG antibody were performed using enzyme-linked immunosorbent assay. Generally, CSF BCG sonicate antigen level and anti-BCG sonicate antibody of patients with tuberculosis meningitis were higher than in control groups; greater antigen levels were found in confirmed patients than in non-inflammatory subjects (p less than 0.05), and in suspected patients than in infectious and non-inflammatory subjects (p less than 0.05 and p less than 0.01). For serum anti-BCG sonicate levels, confirmed patients had higher antibody value than non-inflammatory subjects (p less than 0.05). To conclude, detection of high levels of both BCG sonicate antigen and antibody in CSF and blood samples shows great value in the diagnosis of tuberculous meningitis. However, given the limited samples of the current research, more data are needed to elucidate the sensitivity and specificity of such tests.

Adolescent↗

PubMed1990

[Utilization and medical cost of patients with different insurance coverage among group practice centers].

In order to explore the utilization and medical cost of patients with different insurance coverage in group practice centers, we collected patient data in three centers from September 1, 1987 to February 28, 1988. We classified the payments as self-payment,partial-reimbursement and total-reimbursement. There were 42,234 visits by 8,111 patients. The average frequency of visits within 6 months was 6.1 in total-reimbursement patients, 5.2 in partial-reimbursement patients and 2.6 in self-payment patients. We found that the frequency of visits increased with age in patients with total-reimbursement and partial-reimbursement. On the other hand, the frequency decreased after the age of 65 in patients with self-payment; whether it was related to the economic problems of the elderly needs further study. The highest medical cost per visit was NT$. 343 in total reimbursement patients, followed by NT$. 281 in partial-reimbursement patients. The lowest cost was NT$. 208 in self-payment patients. Yet, the highest ratio of total drug cost by total medical cost per visit was 73.7% in partial-reimbursement patients followed by 63.6% in total-reimbursement patients. The lowest ratio was 56.7% in self-payment patients. Although the partial-reimbursement system could not decrease the ratio of total drug cost by total medical cost per visit, it would be beneficial in group practice centers to decrease the patients' visits and the medical cost per visit. Therefore, this system should be executed in the future.

Adolescent↗

PubMed1990

Antimicrobial activities of six new oral cephem antibiotics.

Six newly developed oral cephem antibiotics, which included 5 with an aminothiazolyl side chain, viz., cefixime, cefotiam hexetil, cefpodoxime proxetil, cefteram pivoxil, ceftibuten, and one with a conventional side chain design, BMY 28100, were tested for their antimicrobial activities. Three traditional oral beta-lactam antibiotics, ampicillin, cephalexin, and cefaclor, were used as reference antibiotics. The 5 aminothiazolyl cephems were more active than the reference drugs against clinical isolates of Escherichia coli, Klebsiella pneumoniae and Haemophilus influenzae. All 6 new drugs showed poor activity against clinical isolates of Enterobacter cloacae, Pseudomonas aeruginosa, and enterococci. They were better than cephalexin and cefaclor, but slightly poorer than or the same as ampicillin in activities against Streptococcus pyogenes and Streptococcus pneumoniae. Cefotiam hexetil, BMY 28100, and cefpodoxime proxetil were also more active than cephalexin against Staphylococcus aureus. Although the 6 tested new oral cephems demonstrated little difference in their activities against different bacteria, they all showed greater antimicrobial activity than the traditional oral antibiotics now in clinical use.

Administration, Oral↗

PubMed1989

Evaluation of clinical diagnosis and stressful life events in patients at a rural family practice centre.

The occurrence of stressful life events in patients might be used as a cue for the diagnosis of psychosocial illness at a consultation where a physical symptom has been presented. In this study 555 patients attending a rural family practice clinic were interviewed about their stressful life events using a questionnaire. Stressful life events had occurred in 44.7% of patients and the total number of events recorded was 624. More life events were found in patients who were female, older and of lower social class. Three types of clinical diagnoses were recognized: simple physical diseases (55.1%) and psychosocial illness with and without physical diseases (36.8% and 8.1% respectively). Patients who were female, older and of lower socioeconomic status and who had experienced more life events had more psychosocial problems than the rest of the group (P less than 0.001). The diagnosis of psychosocial illness could be predicted by the variables of stressful life event and age up to 66%.

Adult↗

PubMed1989

Branhamella keratoconjunctivitis.

A young male complained of monocular diplopia for over a year. Ophthalmic evaluation revealed gross corneal pannus in both eyes and clinical findings precipitated treatment for chronic chlamydial eye disease. The definitive pathogen isolated from both eyes was Branhamella catarrhalis. A cause of otitis media, sinusitis, and lower respiratory infections, Branhamella is a rare, opportunistic ocular pathogen which may be associated with meibomian gland dysfunction.

Adult↗

PubMed1989

A preliminary study of clinical staging in clonorchiasis.

Antibody responses to infection with metacercaria of Clonorchis sinensis were studied in triplet cats. Elevated IgM antibody first appeared seven days after infection, followed by elevation of IgA and IgG. The peak titers of IgM and IgA antibodies were found at 3 weeks and 11 weeks, respectively. IgG antibody was elevated at 3 weeks and reached a peak, then a plateau at 13 weeks. Duration of antibody detection after infection was 1 week to 5 weeks for IgM, and 2 weeks to 28 weeks for IgA. IgM and IgA antibody titers decreased to normal level spontaneously without significant effect by the treatment. Using the animal model, the three clinical stages were classified according to the antibody patterns: i.e. acute stage, IgM(+) IgA(+) IgG(+); subacute stage, IgM(-) IgA(+) IgG(+); Chronic stage, IgM(-) IgA(-) IgG(+). Of 77 human patients with clonorchiasis, there were 3 (3.9%) patients who had subacute infection and 74 (96.1%) patients were in chronic stage.

Animals↗

PubMed1989

Retrospective analysis of 97 patients with infective endocarditis seen over the past 8 years.

The medical records of 97 consecutive patients (101 episodes) of infective endocarditis seen from January 1979 through January 1987 were reviewed. Only 30% of the patients were over 50 years of age and the majority (69%) of infecting organisms were streptococci (mainly of the viridans group), which were similar to those reported from the West in the early antibiotic era. Pseudomonas organisms and enterococci accounted for 6% and 5%, respectively. Fungal infections were noted in 2 patients. There was a high incidence (38%) of predisposing rheumatic valvular disease; approximately half of these patients had prosthetic valve infections. Mitral valve prolapse was also an important predisposing disease (11%). One-third (34%) of the patients had febrile illness for longer than 8 weeks before the diagnosis was established. The hospital morality rate was 22%; cerebral embolism and ruptured mycotic aneurysm, congestive heart failure, and sudden death were the major causes of death. Echocardiography disclosed vegetations on the cardiac valves and preexisting lesions in 75% of the episodes. Early recognition and proper treatment should be the focus of efforts to reduce mortality from infective endocarditis.

Adolescent↗