Biomedical subjects

J-J Wu

Publications and source records attributed to J-J Wu.

13 recordsLinked to original sources

PubMed2006

Articular cartilage collagen: an irreplaceable framework?

Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia syndromes. Here we review what is known of the collagen assembly and present new evidence that collagen type III becomes covalently added to the polymeric fabric of adult human articular cartilage, perhaps as part of a matrix repair or remodelling process.

Amino Acid Sequence↗

PubMed2006

Changes in macrolide resistance among respiratory pathogens after decreased erythromycin consumption in Taiwan.

Measures to alleviate the growing problem of macrolide resistance in Taiwan resulted in a decrease in macrolide consumption, from 0.629 defined daily doses/1000 inhabitants per day (DIDs) in 1999 to 0.301 DIDs in 2003 (a reduction of 52%). A linear relationship was observed between the decline in erythromycin consumption and the decline in erythromycin resistance in Streptococcus pyogenes (46% in 1999 vs. 17% in 2003; p < 0.001) and azithromycin resistance in Haemophilus influenzae (31% in 2000 vs. 0% in 2003; p < 0.001). However, the rate of erythromycin resistance in Streptococcus pneumoniae showed a continued increase, from 80.2% in 1999 to 92% in 2003.

Anti-Bacterial Agents↗

PubMed2006

A rapid enzyme-linked assay for ADAMTS-13.

BACKGROUND: A deficiency in the plasma metalloprotease ADAMTS-13 is associated with deposition of microvascular thrombi that cause thrombotic thrombocytopenic purpura. Current assays for ADAMTS-13 are technically complex and time-consuming. The objective of this study is to devise a rapid and sensitive assay for ADAMTS-13 activity in plasma and verify the site of cleavage. METHOD: A new enzyme-linked substrate, which contains a core ADAMTS-13-specific peptide conjugated to horseradish peroxidase (HRP) at the N-terminus, and labeled with biotin at the C-terminus, was constructed. After cleavage of this substrate by plasma ADAMTS-13 and removal of uncleaved substrate by adsorption with streptavidin-agarose, ADAMTS-13 activity was quantitated by determining the unadsorbed HRP activity remaining in solution. Levels of inhibitory antibodies in test plasma were also determined by measuring the residual ADAMTS-13 activity after varying amounts of test plasma were incubated with a known amount of ADAMTS-13. RESULTS: Plasma ADAMTS-13 activity was readily determined in approximately 60 min (coefficient of variation 5.8%) using 1 microL of test plasma. Amino acid sequencing of the cleavage product confirmed that cleavage occurred at the Tyr1605-Met1606 bond in the substrate. ADAMTS-13 activities in the plasma of five TTP patients were below 2%. Inhibitory antibody titers in these samples varied from undetectable to 81 BU mL(-1). CONCLUSION: The HRP-linked substrate provides a rapid, sensitive, and reproducible way of determining the levels of ADAMTS-13 activity and inhibitory antibodies in plasma.

ADAM Proteins↗

PubMed2005

Esomeprazole 40 mg twice daily in triple therapy and the efficacy of Helicobacter pylori eradication related to CYP2C19 metabolism.

AIM: To determine whether an increased dosage of esomeprazole 40 mg twice daily in triple therapy improved the Helicobacter pylori eradication rate for patients with different genotypes of S-mephenytoin 4'-hydroxylase (CYP2C19). METHODS: Two hundred H. pylori-infected dyspeptic patients were randomized to receive clarithromycin 500 mg twice daily and amoxicillin 1 g twice daily plus either omeprazole 20 mg or esomeprazole 40 mg twice daily for 1 week. Six weeks later, the success of H. pylori eradication was defined. The genotyping of CYP2C19 in each patient was defined as homologous, heterologous extensive metabolizer or poor metabolizer. RESULTS: The age, gender, drug compliance and proportion of CYP2C19 genotypes were similar between the two groups. The H. pylori eradication rates were also similar between the omeprazole group and the esomeprazole group (intention-to-treat analysis: 79% vs. 86%, P > 0.05; per-protocol analysis: 85% vs. 94%, P > 0.05). For patients classified as homologous extensive metabolizers, the per-protocol H. pylori eradication rate was significantly higher in the esomeprazole group than in the omeprazole group (93% vs. 76%, P < 0.05). CONCLUSION: Esomeprazole 40 mg twice daily for triple therapy may improve the H. pylori eradication compared to omeprazole-based therapy, but only for homologous extensive metabolizers of CYP2C19.

Adult↗

PubMed2005

Coagulase-negative staphylococcal meningitis in adults: clinical characteristics and therapeutic outcomes.

BACKGROUND: We wanted to analyze the clinical characteristics and therapeutic outcomes of adult meningitis caused by coagulase-negative staphylococci (CoNS). PATIENTS AND METHODS: Over a period of 5 years (January 1999 to December 2003), 127 cases were identified as having adult culture-proven bacterial meningitis caused by a single pathogen. Of them, 14 cases with CoNS meningitis were enrolled, and their clinical characteristics and therapeutic outcomes were analyzed. RESULTS: The 14 cases (median age 37.5; range 24-77 years old) included nine men and five women. With polynerase chain reaction sequencing of bacterial 16S r-RNA, 10 of the 14 CoNS strains were identified as Staphylococcus epidermidis infection, and the other four belonged to Staphylococcus haemolyticus. All 14 cases were in a postneurosurgical state with insertion of a ventriculoperitoneal shunt, external ventricular device or intrathecal port A as their underlying conditions, and 12 of the 14 patients contracted the infection nosocomially. Fever (86%), leukocytosis (79%), hydrocephalus (50%), consciousness disturbance (36%), and seizure (7%) were the major clinical manifestations. All the involved CoNS strains showed resistance to oxacillin but retained their susceptibility to vancomycin and linezolid. All 14 CoNS strains had positive mecA gene detection. With the removal of neurosurgical devices and intravenous vancomycin therapy, 86% (12/14) of the patients survived. CONCLUSION: CoNS meningitis accounted for 11% (14/127) of our adult bacterial meningitis. All adult CoNS meningitis patients had a disrupted barrier of the central nervous system as the underlying condition. S. epidermidis was the most common CoNS subtype involved. All involved CoNS strains were oxacillin resistant. The therapeutic result showed that adult CoNS meningitis had a mortality rate of 14% (2/14).

Acetamides↗

PubMed2005

Group B streptococcal soft tissue infections in non-pregnant adults.

Skin and soft tissue infections are the most common presentations of invasive Streptococcus agalactiae infections. This study reviewed 71 patients in a medical centre in southern Taiwan with S. agalactiae soft tissue infections. The mortality rate was 7%, and 11% of patients lost their extremities following extensive tissue necrosis. Critical illness and the presence of cutaneous ulceration heralded a fatal prognosis. Risk-factors for amputation of limbs included advanced age, cutaneous ulceration and polymicrobial infection. It was concluded that invasive S. agalactiae soft tissue infections, as with infections caused by Streptococcus pyogenes, can also lead to substantial morbidity and mortality in non-pregnant adults.

Adolescent↗

PubMed2003

Quadruple therapy containing amoxicillin and tetracycline is an effective regimen to rescue failed triple therapy by overcoming the antimicrobial resistance of Helicobacter pylori.

AIM: To identify optimal antibiotics for second-line quadruple therapy of Helicobacter pylori after failed 1-week triple therapy. METHODS: One hundred patients were enrolled in this study after the failure of 1-week triple therapy. They were randomized to receive 1-week quadruple therapy consisting of amoxicillin, omeprazole and bismuth salts, plus either metronidazole or tetracycline. Before quadruple therapy, the H. pylori culture of each patient was tested for metronidazole resistance or clarithromycin resistance by E-test. Six weeks later, an endoscopy or 13C-urea breath test was used to define the success of H. pylori eradication. RESULTS: The H. pylori eradication rates by intention-to-treat and per protocol analysis were higher in the tetracycline group than in the metronidazole group (intention-to-treat: 78% vs. 58%, P < 0.05; per protocol: 89% vs. 67%, P < 0.05). In the metronidazole group, but not in the tetracycline group, the per protocol eradication rate of quadruple therapy was lower for the infected isolates with metronidazole resistance than for those without metronidazole resistance (77% vs. 33%, P < 0.05). CONCLUSION: Quadruple therapy, including tetracycline and amoxicillin, improves the H. pylori eradication rate after failed triple therapy.

Amoxicillin↗

PubMed2003

The selection of triple therapy for Helicobacter pylori eradication in chronic renal insufficiency.

AIM: To establish a triple therapy regimen for Helicobacter pylori eradication in patients with chronic renal insufficiency. METHODS: Eighty-eight patients with chronic renal insufficiency and H. pylori infection were evenly randomized into two groups receiving 1-week lansoprazole, 30 mg, clarithromycin, 500 mg, and either amoxicillin, 750 mg, or metronidazole, 500 mg, twice daily. The adverse events and compliance with triple therapy were reviewed at the week 1 visit. Patients provided stool samples at week 6 to assess the success of H. pylori eradication by H. pylori-specific stool antigen. The serum creatinine levels were monitored at enrollment, at weeks 1, 2 and 6 and on any unscheduled visit after triple therapy. RESULTS: The success of H. pylori eradication was higher in the lansoprazole-clarithromycin-metronidazole group than in the lansoprazole-clarithromycin-amoxicillin group (intention-to-treat analysis: 84% vs. 66%, P < 0.05: per protocol analysis: 93% vs. 76%, P < 0.05). Complete drug compliance was also better in the lansoprazole-clarithromycin-metronidazole group than in the lansoprazole-clarithromycin-amoxicillin group (77% vs. 52%, P < 0.05). Patients in the lansoprazole-clarithromycin-metronidazole group had a lower risk of acute renal failure than those in the lansoprazole-clarithromycin-amoxicillin group (2% vs. 18%, P < 0.05; relative risk, 0.128, 95% confidence interval, 0.016-0.979). CONCLUSIONS: Triple therapy with metronidazole and clarithromycin, but not amoxicillin, can be used for H. pylori eradication in patients with chronic renal insufficiency, because it is more effective, well tolerated and less likely to cause deterioration of renal function.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2003

Host gastric Lewis expression determines the bacterial density of Helicobacter pylori in babA2 genopositive infection.

BACKGROUND AND AIMS: We tested if host gastric Lewis antigens and the babA2 genotype of Helicobacter pylori correlated with clinicohistological outcome. METHODS: We enrolled 188 dyspeptic patients (45 with duodenal ulcer, 45 with gastric ulcer, and 98 with chronic gastritis) with H pylori infection, proved by culture and gastric histology, reviewed by the updated Sydney system. Gastric expression of Lewis (Le) antigens Le(a), Le(b), Le(x), and Le(y) was determined immunochemically to determine intensity (range 0-3). The corresponding 188 H pylori isolates were screened for babA2 genotype by polymerase chain reaction. RESULTS: All H pylori isolates had a positive babA2 genotype. We identified Le(a) in 33.5%, Le(b) in 72.9%, Le(x) in 86.2%, and Le(y) in 97.4% of biopsies from these 188 patients. Patients who expressed Le(b) had a higher H pylori density than those who did not express Le(b) (p<0.001). Among 139 patients who expressed Le(b), H pylori density increased with a higher Le(b) intensity (p<0.05). Gastric atrophy decreased with Le(b) intensity and thus resulted in lower H pylori density in the antrum (p<0.05). For the 49 patients without gastric Le(b) expression, H pylori density was positively related with Le(x) and Le(a) expression (p<0.05). CONCLUSIONS: Taiwanese H pylori isolates are 100% babA2 genopositive. Gastric Le(b) as well as Le(x) intensity may be major determinants of H pylori density. While lacking gastric Le(b) expression, Le(x) and Le(a) were closely related to H pylori colonisation.

Adhesins, Bacterial↗

PubMed2002

Analysis of risk factors for bacteremia in children with nontyphoidal Salmonella gastroenteritis.

To identify the risk factors for Salmonella bacteremia in infants and children with Salmonella gastroenteritis, a retrospective study of a 10-year period was conducted to evaluate 456 infants and children with culture-proven nontyphoidal Salmonella infection. Salmonella typhimurium was the most common isolate found. Among the 257 patients with gastroenteritis who had a concomitant blood culture performed, 50 exhibited bacteremia. Statistically significant differences were noted between patients with gastroenteritis and bacteremia and those without bacteremia in duration of fever > or = 5 days ( P < 0.001; OR, 5.6; 95% CI, 2.6 - 12.1) and infection with group D1 Salmonella ( P < 0.001; OR, 6.5; 95% CI, 2.5 - 16.9) after adjustment for multivariate analysis. Of the 320 Salmonella strains that were serotyped, Salmonella panama was shown to be strongly associated with bacteremia ( P<0.001) in children with gastroenteritis. In summary, in children with nontyphoidal Salmonella gastroenteritis, prolonged fever lasting 5 days or more and infection with a specific Salmonella serotype were risk factors closely associated with development of bacteremia.

Adolescent↗

PubMed2002

Collagen polymorphisms of the intervertebral disc.

The mechanical function and the collagen phenotype of the disc are complex, each a hybrid of elements of ligament and cartilage. In detail, the collagen properties are unique. Collagens I and II provide the bulk of the tissue fabric interwoven in opposing radial concentration gradients. From analysis of isolated cross-linked peptides, some degree of commingling of these major fibrillar collagens occurs down to the molecular level. Collagens V, VI, IX, XI, XII and XIV all contribute to the matrix. Collagen IX is the short molecular form that lacks a non-collagenous (NC)4 domain, not the long form found in most hyaline cartilages. Protein sequence and reverse transcriptase-PCR analysis confirmed this was the result of expression from the alternative transcription start site, not proteolysis of the long form. In view of recent reports that common single nucleotide polymorphisms in COL9A2 and COL9A3 are linked to chronic sciatica associated with disc pathology, the specific interactions and role of collagen IX in disc tissue are important to define.

Animals↗

PubMed2002

Impact of supplement with Lactobacillus- and Bifidobacterium-containing yogurt on triple therapy for Helicobacter pylori eradication.

AIM: To test whether supplements of Lactobacillus- and Bifidobacterium-containing yogurt (AB-Yogurt) affect the success of Helicobacter pylori eradication. METHODS: One hundred and sixty H. pylori-infected patients were randomized into a triple-plus-yogurt group or a triple-only group, receiving 1 week of triple therapy with and without supplements of AB-Yogurt, respectively. In the triple-plus-yogurt group, AB-Yogurt was continued for 4 weeks after triple therapy. Eight weeks later, patients were assessed for the success of H. pylori eradication. The stool samples of 22 randomly selected patients, 11 from each group, were provided on enrolment, at the first week and at the fifth week for evaluation of the percentage of Bifidobacterium in anaerobes. RESULTS: By intention-to-treat analysis, the triple-plus-yogurt group had a higher H. pylori eradication rate than the triple-only group (91% vs. 78%, P < 0.05). The per protocol H. pylori eradication rates were similar for both groups (93.5% vs. 89%, P = N.S.). Only patients supplemented with AB-Yogurt showed restoration of the percentage of Bifidobacterium in the anaerobes of stools at the fifth week to the level in the stools on enrolment. CONCLUSIONS: Supplement with AB-Yogurt can improve the intention-to-treat eradication rates of H. pylori, and can restore the depletion of Bifidobacterium in stools after triple therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2002

Bacterial brain abscess: microbiological features, epidemiological trends and therapeutic outcomes.

BACKGROUND: Despite the advent of modern neurosurgical techniques, new antibiotics, and powerful imaging technologies, brain abscess remains a potentially fatal central nervous system infection. AIM: To determine the epidemiological trends, prognostic factors, and outcomes of bacterial brain abscess, to improve the therapeutic strategy for this disease. DESIGN: Retrospective hospital-based epidemiology study. METHODS: Over a period of 15 years (1986-2000), 123 patients were retrospectively identified as having brain abscesses at Kaohsiung Chang Gung Memorial Hospital. To compare changes over time, the appearance of disease among our patients was divided into two time periods: 1986-1993 and 1994-2000. RESULTS: The prevalence rate of brain abscesses caused by Gram-negative organisms significantly increased in the second study period. Viridans streptococci and Klebsiella pneumoniae were the two prevalent pathogens associated with haematogenous spread. Metastatic septic abscess, a devastating complication of K. pneumoniae septicaemia, frequently occurs in diabetic patients, with a high mortality rate. Viridans streptococci were the most prevalent pathogens from infection in paranasal sinusitis, but no fatality occurred. In recent years, head trauma and/or post-neurosurgical states have become important predisposing factors, and nosocomial infections also play an important role. DISCUSSION: Despite the availability of new antibiotics and the development of better neurosurgical techniques, therapeutic outcomes of brain abscess showed no significant change when comparing the two study periods, and only the presence of septic shock influenced outcome.

Adolescent↗