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Chen YC, Chang SC, Tai HM, Hsueh PR, Luh KT. Molecular epidemiology of Candida colonizing critically ill patients in intensive care units. J Formos Med Assoc 2001; 100:791-7. [PMID: 11802517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
BACKGROUND AND PURPOSE Nosocomial Candida infections are an important cause of morbidity and mortality in critically ill patients. Although there is growing evidence that candidemia develops primarily as a consequence of endogenous colonization, hospital outbreaks of Candida infection are not uncommon. To examine the prevalence and consequence of Candida colonization in critically ill patients and to elucidate the contribution of cross-transmission to the high frequency of nosocomial fungal infection in intensive care units (ICUs), a 6-month prospective surveillance study was conducted. PATIENTS AND METHODS A total of 342 adult patients with an expected ICU stay of 48 hours or more were enrolled in the study. Surveillance cultures were taken from the rectal region, oropharynx, and urine on ICU entry and weekly thereafter. The electrophoretic karyotypes (EKs) of all isolates were characterized using pulsed-field gel electrophoresis. RESULTS A total of 873 Candida strains were isolated from 208 of the 342 patients (60.8%) during ICU stay. A comparison of the EK patterns generated from Candida strains isolated from different patients demonstrated a variability of karyotypes, and failed to identify predominant clones colonizing or infecting ICU patients. For 62 of 102 patients colonized with multiple isolates of the same Candida spp., the EK patterns of the Candida strains isolated from individual patients were identical or similar, even when isolated from different anatomical sites, and the patterns remained the same for up to 62 days. A total of 57 episodes of Candida infection occurred in 53 (25.5%) of these 208 patients. Thirty-six episodes (63.1%) of Candida infection were preceded by colonization with the same Candida spp. All infecting strains had identical or similar EK patterns to prior colonizing strains. CONCLUSIONS While Candida colonization was common in ICU patients, karyotyping did not identify cross-transmission among these patients. Further, only 25.5% of patients with Candida colonization subsequently developed Candida infection. These findings suggest that universal prophylaxis is not warranted in critically ill patients with Candida colonization.
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Hsieh SM, Pan SC, Hung CC, Tsai HC, Chen MY, Lee CN, Chang SC. Kinetics of antigen-induced phenotypic and functional maturation of human monocyte-derived dendritic cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:6286-91. [PMID: 11714792 DOI: 10.4049/jimmunol.167.11.6286] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Dendritic cells (DCs), a critical component of innate immunity, are the most potent APCs. When DCs mature, they can elicit strong T cell responses. We studied the kinetics of Ag-induced phenotypic and functional maturation of human monocyte-derived DCs using an in vitro T cell-independent culture system. With this model, we herein show that an Ag that has recently or repetitively been exposed ("exposed Ag") rapidly induces a high level of maturation; however, an Ag that has never or only remotely been exposed ("unexposed Ag") slowly induces a low level of maturation. The kinetics of Ag-induced maturation of DCs possibly implies a novel mechanism for immunological memory that would provide maximal host protection from repetitively invading pathogens in the environment.
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Chang SC, Sommer RD, Rheingold AL, Goldberg DP. A model complex of a possible intermediate in the mechanism of action of peptide deformylase: first example of an (N2S)zinc(II)-formate complex. Chem Commun (Camb) 2001:2396-7. [PMID: 12240093 DOI: 10.1039/b106865m] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis and crystallographic characterization of a new (N2S)zinc-alkyl complex and (N2S)zinc-formate complex is described; the bonding mode of the formate complex has implications for the mechanism of action of the enzyme peptide deformylase.
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Chang SC, Kao MC, Fu MT, Lin CT. Modulation of NO and cytokines in microglial cells by Cu/Zn-superoxide dismutase. Free Radic Biol Med 2001; 31:1084-9. [PMID: 11677041 DOI: 10.1016/s0891-5849(01)00691-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The activation of microglial cells in response to neuropathological stimuli is one of the prominent features of human neurodegenerative diseases. Cytokines such as IL-1 beta and TNF-alpha and inflammation-related enzymes such as inducible nitric oxide synthase are usually induced during the activation of microglial cells. We investigated the modulation of the activation of microglial cell by transfecting a Cu/Zn-SOD cDNA into BV-2 cells. Parental and transfected BV-2 cells were then subjected to LPS stimulation. The results showed that in Cu/Zn-SOD-transfected BV-2 cells, the expression and activity of Cu/Zn-SOD increased. On the other hand, upon activation by LPS, these cells produced less NO, IL-1 beta, and TNF-alpha than the parental microglial cells. This finding suggests that superoxide may be an early signal triggering the induction of cytokines and that the transfected Cu/Zn-SOD may provide a neuroprotective function via suppression of microglial activation. In addition, this approach may provide a rationale for the development of treatments for neurodegenerative diseases.
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Chen YC, Lin SF, Liu CJ, Jiang DD, Yang PC, Chang SC. Risk factors for ICU mortality in critically ill patients. J Formos Med Assoc 2001; 100:656-61. [PMID: 11760370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
BACKGROUND AND PURPOSE Advances in critical care medicine have increased the chances of survival for patients with severe illness or trauma. However, such patients consume a large proportion of medical resources. This study sought risk factors for mortality that have potential to be modified among patients treated in medical or surgical intensive care units (ICUs). METHODS This 6-month prospective observational study was conducted in the medical and surgical ICUs of an 1,800-bed university hospital. All adult patients with an expected ICU stay of 48 hours or more were followed up regularly until discharge from the ICUs, or for 10 weeks during their stay in ICUs. RESULTS Of 342 patients enrolled, 77 (22.5%) died during a median follow-up period of 5 days (range, 2-70 days). Among a range of variables at the time of ICU entry or developing during stay in ICUs, 17 were associated with higher mortality rate. Multivariate analysis using a logistic regression model demonstrated that the presence of systemic inflammatory response syndrome (SIRS) at the time of ICU entry (adjusted relative risk, ARR, 2.85; 95% confidence interval, CI, 1.16-7.05), Acute Physiological and Chronic Health Evaluation (APACHE) II score on ICU Day 4 (ARR 1.12 with increment of one score; 95% CI 1.01-1.24), Therapeutic Intervention Scoring System (TISS) score on Day 4 (ARR 1.13 with increment of one score; 95% CI 1.05-1.23), parenteral nutrition (ARR 4.97, 95% CI 1.73-14.26), and nosocomial Candida infection (ARR 3.39, 95% CI 1.12-10.23) were independently associated with ICU mortality. CONCLUSIONS In addition to SIRS and the APACHE II and TISS scores, this study found that nosocomial Candida infection and parenteral nutrition were independently associated with mortality after control for admission conditions, severity of illness scores, and interventions.
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Lin FC, Chang SC. Plate atelectasis: an implication of foreign body aspiration into the lower airways in two adults. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2001; 64:597-602. [PMID: 11791948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Pneumonic patches and atelectatic or bronchiectatic changes in the tributary lung distal to the bronchial foreign body are common radiographic abnormal findings in adults with foreign body aspiration into the lower airways. Nevertheless, plate (plate-like or discoid) atelectasis, a form of peripheral atelectasis, has not been reported to associate with this condition. In this report, we describe two men with the foreign body impacted in the right intermediate bronchus. In both cases, plate atelectasis was found in the base of the right lung and disappeared after successful removal of the foreign body via fiberoptic bronchoscopy. These two cases illustrate that plate atelectasis may be an implication of foreign body aspiration into the lower airways.
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Wang JT, Yao M, Tang JL, Chang SC, Hung CC. Prior invasive fungal infection is not a contraindication for subsequent allogeneic bone marrow transplantation in adult patients with hematologic malignancies. J Clin Oncol 2001; 19:4000-1. [PMID: 11579127 DOI: 10.1200/jco.2001.19.19.4000] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Sue SC, Brisson JR, Chang SC, Huang WN, Lee SC, Jarrell HC, Wu W. Structures of heparin-derived disaccharide bound to cobra cardiotoxins: context-dependent conformational change of heparin upon binding to the rigid core of the three-fingered toxin. Biochemistry 2001; 40:10436-46. [PMID: 11523985 DOI: 10.1021/bi010847n] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glycosaminoglycans (GAGs) have been suggested to be a potential target for cobra cardiotoxin (CTX) with high affinity and specificity via a cationic belt at the concave surface of the polypeptide. The interaction of GAGs, such as high-molecular weight heparin, with CTXs not only can induce aggregation of CTX molecules but also can enhance their penetration into membranes. The binding of short chain heparin, such as a heparin-derived disaccharide [DeltaUA2S(1-->4)-alpha-D-GlcNS6S], to CTX A3 from Taiwan cobra (Naja atra), however, will not induce aggregation and was, therefore, investigated by high-resolution (1)H NMR. A novel heparin binding site on the convex side of the CTX, near the rigid disulfide bond-tightened core region of Cys38, was identified due to the observation of intermolecular NOEs between the protein and carbohydrate. The derived carbohydrate conformation using complete relaxation and conformational exchange matrix analysis (CORCEMA) of NOEs indicated that the glycosidic linkage conformation and the ring conformation of the unsaturated uronic acid in the bound state depended significantly on the charge context of CTX molecules near the binding site. Specifically, comparative binding studies of several heparin disaccharide homologues with two CTX homologues (CTX Tgamma from Naja nigricollis and CTX A3) indicated that the electrostatic interaction of N-sulfate of glucosamine with NH(3)(+)zeta of Lys12 and of the 2-O-sulfate of the unsaturated uronic acid with NH(3)(+)zeta of Lys5 played an important role. These results also suggest a model on how the CTX-heparin interaction may regulate heparin-induced aggregation of the toxin via the second heparin binding site.
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Fang CT, Chang SC, Chen YC, Hsieh SM, Hsieh WC. In vitro activity of linezolid against clinical Gram-positive bacterial isolates from Taiwan: an area with a high prevalence of antibiotic resistance. Int J Antimicrob Agents 2001; 18:267-70. [PMID: 11673041 DOI: 10.1016/s0924-8579(01)00384-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The prevalence of antibiotic-resistant bacteria in Taiwan is due to the heavy use of antimicrobial agents in both animal husbandry and clinical practice over the past decades. Minimum inhibitory concentrations (MICs) of linezolid were established for 371 clinical isolates of staphylococci, pneumococci, enterococci and group A streptococci from Taiwan. All isolates tested including those resistant to beta-lactams, erythromycin, vancomycin and quinupristin-dalfopristin were uniformly susceptible to linezolid, with MICs ranging from 0.125 to 2 mg/l. Our data support the observation that there is no cross-resistance between linezolid and other classes of antimicrobial substances.
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Sheng WH, Wang JT, Chen YC, Chang SC, Luh KT. In vitro activity of moxifloxacin against common clinical bacterial isolates in Taiwan. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2001; 34:178-84. [PMID: 11605808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The in vitro antimicrobial activities of moxifloxacin were compared with 7 other antimicrobial agents. A total of 707 isolates of 11 common pathogenic bacteria were collected from the National Taiwan University Hospital; antimicrobial activities against these isolates were evaluated by minimum inhibitory concentration using an agar-dilution method. Most common pathogenic bacteria were susceptible to moxifloxacin, including methicillin-susceptible and -resistant Staphylococcus aureus, methicillin-susceptible and -resistant Staphylococcus epidermidis, Streptococcus pneumoniae, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, Burkholderia cepacia, Acinetobacter baumannii, and Stenotrophomonas maltophilia. For many of these bacterial species, moxifloxacin was the most active antimicrobial agent compared with the third- and fourth- generation cephalosporins, carbapenems, monobactam, and other quinolones. Some strains of methicillin-resistant S. aureus and methicillin-resistant S. epidermidis demonstrated very low levels of minimum inhibitory concentration for moxifloxacin, suggesting the potential application of the drug to treat some drug-resistant gram-positive bacterial infections. Moxifloxacin was less active against P. aeruginosa, but was more active against S. maltophilia when compared with other fluoroquinolones. In conclusion, moxifloxacin exhibits an increased potency against gram-positive bacteria as compared with other tested antimicrobial agents, while preserving excellent activity against gram-negative bacteria. The drug appears to be a promising agent expressing activity against a wide variety of bacteria in Taiwan.
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Chang ST, Chen PF, Chang SC. Antibacterial activity of leaf essential oils and their constituents from Cinnamomum osmophloeum. JOURNAL OF ETHNOPHARMACOLOGY 2001; 77:123-127. [PMID: 11483389 DOI: 10.1016/s0378-8741(01)00273-2] [Citation(s) in RCA: 256] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The antibacterial activities of the essential oils from leaves of two Cinnamomum osmophloeum clones (A and B) and their chemical constituents were investigated in this study. The nine strains of bacteria, including Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, Salmonella sp., and Vibrio parahemolyticus, were used in the antibacterial tests. Results from the antibacterial tests demonstrated that the indigenous cinnamon B leaf essential oils had an excellent inhibitory effect. The MICs (minimum inhibitory concentrations) of the B leaf oil were 500 microg/ml against both K. pneumoniae and Salmonella sp. and 250 microg/ml against the other seven strains of bacteria. Cinnamaldehyde possessed the strongest antibacterial activity compared to the other constituents of the essential oils. The MICs of cinnamaldehyde against the E. coli, P. aeruginosa, E. faecalis, S. aureus, S. epidermidis, MRSA, K. pneumoniae, Salmonella sp., and V. parahemolyticus were 500, 1000, 250, 250, 250, 250, 1000, 500, and 250 microg/ml, respectively. These results suggest that C. osmophloeum leaf essential oil and cinnamaldehyde are beneficial to human health, having the potential to be used for medical purposes and to be utilized as anti-bacterial additives in making paper products.
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Wu WB, Chang SC, Liau MY, Huang TF. Purification, molecular cloning and mechanism of action of graminelysin I, a snake-venom-derived metalloproteinase that induces apoptosis of human endothelial cells. Biochem J 2001; 357:719-28. [PMID: 11463342 PMCID: PMC1222001 DOI: 10.1042/0264-6021:3570719] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Apoptosis, a programmed, physiological mode of cell death, is important in tissue homoeostasis. Here we report that a new metalloproteinase, graminelysin I, purified from Trimeresurus gramineus venom, induced apoptosis of human endothelial cells as examined by electrophoresis and flow cytometry. Graminelysin I contains only a metalloproteinase domain. It is a single-chain proteinase with a molecular mass of 27020 Da. cDNA sequence analysis revealed that the disintegrin-like and cysteine-rich domains of the putative precursor protein of graminelysin I are likely to be processed post-translationally, producing the proteinase domain (graminelysin I). Graminelysin I cleaved the alpha chain of fibrinogen preferentially and cleaved the beta chain either on longer incubation or at higher concentration. Graminelysin I inhibited the adhesion of human umbilical-vein endothelial cells (HUVECs) to immobilized fibrinogen and induced HUVECs detachment in a dose-dependent manner. These effects on HUVECs were abolished when graminelysin I was pretreated with EDTA. However, graminelysin I did not inhibit the adhesion of HUVECs to immobilized collagen. HUVECs were susceptible to death after treatment with graminelysin I when they were cultured on immobilized fibrinogen. In contrast, HUVECs were rather resistant to treatment with graminelysin I if they were cultured on immobilized collagen. Furthermore, graminelysin I induced apoptosis of HUVECs in a dose-dependent manner. Similarly, its apoptosis-inducing activity was blocked if it was treated with EDTA. These results suggest that the catalytic activity of graminelysin I on matrix proteins contributes to its apoptosis-inducing activity.
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Chang SC, Shiu MN, Chen TJ. Antibiotic usage in primary care units in Taiwan after the institution of national health insurance. Diagn Microbiol Infect Dis 2001; 40:137-43. [PMID: 11502383 DOI: 10.1016/s0732-8893(01)00256-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To understand antibiotic usage in primary care units in Taiwan after the institution of national health insurance, we collected all prescriptions for one week in March each year from 1996 to 1999 from out-patient clinics of randomly sampled public health stations located in various parts of Taiwan. We sampled 114 health stations with 40,891 patient-visits and 68,386 diagnoses made in 1996; 154 health stations were sampled with 53,992 patient-visits and 99,466 diagnoses in 1997; 166 health stations were sampled with 49,112 patient-visits and 96,161 diagnoses in 1998; and 162 health stations were sampled with 46,976 patient-visits and 93,641 diagnoses in 1999. The percentages of total patient-visits that resulted in antibiotic treatment were 14.2%, 12.5%, 14.1% and 13.0% in the four time periods, respectively. Among patient-visits, patient group under the age of 11 received the highest percentage of antibiotic treatment. Common cold was the most frequent diagnosis for which antibiotic was prescribed during the four time periods, accounting for 32.3% of total antibiotic prescriptions. Among patients with the diagnosis of common cold, 31.3% received antibiotic treatment, and the highest figure was among pediatric patients (<16 year of age). Penicillins, cephalosporins and macrolides were the most commonly prescribed classes of antibiotics. They accounted for 35.4%, 26.5% and 21.6% of all prescribed antibiotics in these four study periods. From this study, it was found that, after institution of the national health insurance system, antibiotics are still very commonly used in primary care units in Taiwan and still seem to be overused.
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Liang JD, Fang CT, Chen YC, Chang SC, Luh KT. Candida albicans spinal epidural abscess secondary to prosthetic valve endocarditis. Diagn Microbiol Infect Dis 2001; 40:121-3. [PMID: 11502380 DOI: 10.1016/s0732-8893(01)00252-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A 56-year-old woman, with underlying rheumatic heart disease status post mitral valve replacement, presented with fever, low back pain radiating to right leg, and congestive heart failure. Magnetic resonance imaging detected an L5-S1 spinal epidural abscess. A vegetation on prosthetic mitral valve was found by transesophageal echocardiography. Cultures of epidural aspirate, surgical specimen, and blood all grew Candida albicans. She received surgical drainage of the spinal epidural abscess and i.v. amphotericin B 1 mg/kg/day for eight weeks. Clinical symptoms improved gradually and she was discharged without neurologic sequelae. She remained well and continued to lead an active life two years after discharge.
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Chang SC, Rowley JA, Tobias G, Genes NG, Roy AK, Mooney DJ, Vacanti CA, Bonassar LJ. Injection molding of chondrocyte/alginate constructs in the shape of facial implants. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 55:503-11. [PMID: 11288078 DOI: 10.1002/1097-4636(20010615)55:4<503::aid-jbm1043>3.0.co;2-s] [Citation(s) in RCA: 231] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Over one million patients per year undergo some type of procedure involving cartilage reconstruction. Polymer hydrogels, such as alginate, have been shown to be effective carriers for chondrocytes in subcutaneous cartilage formation. The goal of our current study was to develop a method to create complex structures (nose bridge, chin, etc.) with good dimensional tolerance to form cartilage in specific shapes. Molds of facial implants were prepared using Silastic ERTV. Suspensions of chondrocytes in 2% alginate were gelled by mixing with CaSO(4) (0.2 g/mL) and injected into the molds. Constructs of various cell concentrations (10, 25, and 50 million/mL) were implanted in the dorsal aspect of nude mice and harvested at times up to 30 weeks. Analysis of implanted constructs indicated progressive cartilage formation with time. Proteoglycan and collagen constructs increased with time to approximately 60% that of native tissue. Equilibrium modulus likewise increased with time to 15% that of normal tissue, whereas hydraulic permeability decreased to 20 times that of native tissue. Implants seeded with greater concentrations of cells increased proteoglycan content and collagen content and equilibrium and decreased permeability. Production of shaped cartilage implants by this technique presents several advantages, including good dimensional tolerance, high sample-to-sample reproducibility, and high cell viability. This system may be useful in the large-scale production of precisely shaped cartilage implants.
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Saint-Dic D, Chang SC, Taylor GS, Provot MM, Ross TS. Regulation of the Src homology 2-containing inositol 5-phosphatase SHIP1 in HIP1/PDGFbeta R-transformed cells. J Biol Chem 2001; 276:21192-8. [PMID: 11287412 DOI: 10.1074/jbc.m008336200] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has been shown previously that the Huntingtin interacting protein 1 gene (HIP1) was fused to the platelet-derived growth factor beta receptor gene (PDGFbetaR) in leukemic cells of a patient with chronic myelomonocytic leukemia. This resulted in the expression of the chimeric HIP1/PDGFbetaR protein, which oligomerizes, is constitutively tyrosine-phosphorylated, and transforms the Ba/F3 murine hematopoietic cell line to interleukin-3-independent growth. Tyrosine phosphorylation of a 130-kDa protein (p130) correlates with transformation by HIP1/PDGFbetaR and related transforming mutants. We report here that the p130 band is immunologically related to the 125-kDa isoform of the Src homology 2-containing inositol 5-phosphatase, SHIP1. We have found that SHIP1 associates and colocalizes with the HIP1/PDGFbetaR fusion protein and related transforming mutants. These mutants include a mutant that has eight Src homology 2-binding phosphotyrosines mutated to phenylalanine. In contrast, SHIP1 does not associate with H/P(KI), the kinase-dead form of HIP1/PDGFbetaR. We also report that phosphorylation of SHIP1 by HIP1/PDGFbetaR does not change its 5-phosphatase-specific activity. This suggests that phosphorylation and possible PDGFbetaR-mediated sequestration of SHIP1 from its substrates (PtdIns(3,4,5)P(3) and Ins(1,3,4,5)P(4)) might alter the levels of these inositol-containing signal transduction molecules, resulting in activation of downstream effectors of cellular proliferation and/or survival.
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Chang SC, Cho MH, Kang BG, Kaufman PB. Changes in starch content in oat (Avena sativa) shoot pulvini during the gravitropic response. JOURNAL OF EXPERIMENTAL BOTANY 2001; 52:1029-1040. [PMID: 11432919 DOI: 10.1093/jexbot/52.358.1029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to determine if components of the signal transduction pathway are involved in starch metabolism during the gravitropic response, the effects of inhibitors of phosphoprotein phosphatases and protein kinases (OA), and calcium channel blockers (LaCl3), on gravitropic bending and starch levels in gravisensitive node/pulvini of oat shoots were examined. Among the compounds tested, okadaic acid (OA) and lanthanum chloride (LaCl3) showed the strongest inhibitory effects on the negative gravitropic curvature response in oat shoot node/pulvini. At the same time, they caused a rapid loss of starch in graviresponding pulvini based on a quantitative analysis of starch levels in the bending tissues over 48 h periods. These two compounds act initially to block the net increase in starch content that occurs during the early stages (0-9 h) in graviresponding oat shoot pulvini. As a result, starch levels drop precipitously in shoots treated with OA and LaCl3, starting at time zero of gravistimulation by reorientation. These findings suggest that protein dephosphorylation and calcium play a role in starch metabolism in oat shoot pulvini in response to a gravistimulation signal. They also indicate that the amount of starch present in the chloroplast gravisensors in oat shoot pulvini may determine the rate of upward bending in graviresponding pulvini.
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Lee CH, Chang SC, Wu CH, Chang MF. A novel chromosome region maintenance 1-independent nuclear export signal of the large form of hepatitis delta antigen that is required for the viral assembly. J Biol Chem 2001; 276:8142-8. [PMID: 11076934 DOI: 10.1074/jbc.m004477200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hepatitis delta virus (HDV) is a satellite virus of hepatitis B virus, as it requires hepatitis B virus for virion production and transmission. We have previously demonstrated that sequences within the C-terminal 19-amino acid domain flanking the isoprenylation motif of the large hepatitis delta antigen (HDAg-L) are important for virion assembly. In this study, site-directed mutagenesis and immunofluorescence staining demonstrated that in the absence of hepatitis B virus surface antigen (HBsAg), the wild-type HDAg-L was localized in the nuclei of transfected COS7 cells. Nevertheless, in the presence of HBsAg, the HDAg-L became both nuclei- and cytoplasm-distributed in about half of the cells. An HDAg-L mutant with a substitution of Pro-205 to alanine could neither form HDV-like particles nor shift the subcellular localization in the presence of HBsAg. In addition, nuclear trafficking of HDAg-L in heterokaryons indicated that HDAg-L is a nucleocytoplasmic shuttling protein. A proline-rich HDAg peptide spanning amino acid residues 198 to 210, designated NES(HDAg-L), can function as a nuclear export signal (NES) in Xenopus oocytes. Pro-205 is critical for the NES function. Furthermore, assembly of HDV is insensitive to leptomycin B, indicating that the NES(HDAg-L) directs nuclear export of HDAg-L to the cytoplasm via a chromosome region maintenance 1-independent pathway.
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Perera IY, Heilmann I, Chang SC, Boss WF, Kaufman PB. A role for inositol 1,4,5-trisphosphate in gravitropic signaling and the retention of cold-perceived gravistimulation of oat shoot pulvini. PLANT PHYSIOLOGY 2001; 125:1499-507. [PMID: 11244128 PMCID: PMC65627 DOI: 10.1104/pp.125.3.1499] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2000] [Revised: 10/25/2000] [Accepted: 11/20/2000] [Indexed: 05/18/2023]
Abstract
Plants sense positional changes relative to the gravity vector. To date, the signaling processes by which the perception of a gravistimulus is linked to the initiation of differential growth are poorly defined. We have investigated the role of inositol 1,4,5-trisphosphate (InsP(3)) in the gravitropic response of oat (Avena sativa) shoot pulvini. Within 15 s of gravistimulation, InsP(3) levels increased 3-fold over vertical controls in upper and lower pulvinus halves and fluctuated in both pulvinus halves over the first minutes. Between 10 and 30 min of gravistimulation, InsP(3) levels in the lower pulvinus half increased 3-fold over the upper. Changes in InsP(3) were confined to the pulvinus and were not detected in internodal tissue, highlighting the importance of the pulvinus for both graviperception and response. Inhibition of phospholipase C blocked the long-term increase in InsP(3), and reduced gravitropic bending by 65%. Short-term changes in InsP(3) were unimpaired by the inhibitor. Gravitropic bending of oat plants is inhibited at 4 degrees C; however, the plants retain the information of a positional change and respond at room temperature. Both short- and long-term changes in InsP(3) were present at 4 degrees C. We propose a role for InsP(3) in the establishment of tissue polarity during the gravitropic response of oat pulvini. InsP(3) may be involved in the retention of cold-perceived gravistimulation by providing positional information in the pulvini prior to the redistribution of auxin.
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Chang SC, Chen YC, Hu OY. Antibiotic use in public hospitals in Taiwan after the implementation of National Health Insurance. J Formos Med Assoc 2001; 100:155-61. [PMID: 11393108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
BACKGROUND AND PURPOSE Only limited data is available on the patterns of antibiotic use in hospitals in Taiwan before and after the implementation of national health insurance. This study aimed to determine the patterns of use of antibiotics in public hospitals in Taiwan after the implementation of the National Health Insurance program and to compare these with patterns prior to the implementation. METHODS Data on the annual use of all antibiotics in public hospitals in Taiwan during the period from fiscal year (FY) 1994-1995 to 1997-1998 were collected and analyzed. Hospitals included seven medical centers, 19 regional hospitals, 53 district hospitals, and eight specialty service hospitals. RESULTS The annual cost of antibiotics made up 17.4% of the annual cost of all medication used in these hospitals in FY 1994-1995, and decreased year by year to 12.6% in FY 1997-1998. During the study period, 57.4% of the total cost of antibiotics were incurred by medical centers, 24.6% by regional hospitals, 16.2% by district hospitals, and 1.8% by specialty service hospitals. The most commonly used class of antibiotic was cephalosporins, accounting for 48.0% to 54.3% of total antibiotic costs. The second most commonly used class of antibiotic was penicillins, accounting for 15.9% to 17.4% of total antibiotic costs. In FY 1994-1995, the next most commonly used classes of antibiotics were aminoglycosides, fluoroquinolones, and other beta-lactams, respectively, but by FY 1997-1998 these had changed to fluoroquinolones, glycopeptides, and aminoglycosides, respectively. Among the various cephalosporins used, first-generation cephalosporins accounted for 76.1% of all cephalosporins used in FY 1994-1995, which increased year by year to 84.0% in FY 1997-1998. Second-generation cephalosporins accounted for 20.7% of all cephalosporins used in FY 1994-1995, decreasing to 13.2% in FY 1997-1998. CONCLUSION The introduction of the National Health Insurance program in Taiwan brought about a major change in antibiotic use patterns in public hospitals.
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Wu WM, Chiang BL, Chang SC, Lin BF. Dietary fish oil increases CD8+ T-cells and decreases autoreactive T-cell activity in autoimmune NZB/W F1 mice. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2001; 34:41-9. [PMID: 11321127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
To further elucidate the effect of different dietary fats on the pathogenesis of autoimmune diseases, five groups of New Zealand black/white (NZB/W) F1 mice were fed diets containing 200 g of different dietary fats including palm oil, lard-soybean oil (1:1, w/w), soybean oil, canola oil or fish oil. Serum levels of anti-DNA antibodies, proteinuria were followed every month and life span of the mice was determined. After 5 months of the respective diets, mice were killed at the age of 7 months and phenotypic analysis of splenic cells and peritoneal resident cells was performed. The pattern of production of cytokines in splenic T-cells was also investigated. The peritoneal resident cells were isolated for measurement of prostaglandin E2 (PGE2) levels. Significantly lower immunoglobulin G (IgG) anti-single-stranded DNA (ssDNA) and anti-double-stranded DNA (dsDNA) antibody levels were associated with less severe proteinuria and prolonged life span in mice fed dietary fish oil compared to mice fed other dietary oils. Phenotypic analysis of spleen cells showed increased CD8+ T-cells in the mice fed dietary fish oil compared to mice of the other dietary groups, and the percentage of natural killer (NK) cells in the mice fed dietary fish oil was also higher compared to the other dietary groups. The peritoneal resident cells produced lower PGE2 in mice fed fish oil compared to mice in the other dietary groups. To further investigate the effect of fish oil on autoreactive T-cells, splenic T-cells purified using a nylon wool column were stimulated with non-T-cells of young NZB/W F1 mice. Our data suggest that the anti-DNA antibody augmentation ability of T-cells in mice fed dietary fish oil was significantly decreased compared to mice in the other dietary groups. These data indicate that dietary fish oil might maintain the existence of CD8+ T-cells, decrease autoreactive T-cell activity and alleviate subsequent autoimmune processes in autoimmune prone NZB/W F1 mice.
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Chou CW, Lin FC, Tung SM, Liou RD, Chang SC. Diagnosis of pulmonary alveolar proteinosis: usefulness of papanicolaou-stained smears of bronchoalveolar lavage fluid. ARCHIVES OF INTERNAL MEDICINE 2001; 161:562-6. [PMID: 11252115 DOI: 10.1001/archinte.161.4.562] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The globules (stained green, orange, or orange in the center coated with a green rim) seen in Papanicolaou-stained smears of bronchoalveolar lavage fluid are suggested to be characteristic of pulmonary alveolar proteinosis (PAP). OBJECTIVE To evaluate the usefulness of Papanicolaou-stained smears of bronchoalveolar lavage fluid in aiding a diagnosis of PAP. METHODS Papanicolaou-stained smears of bronchoalveolar lavage fluid obtained from 7 patients (5 idiopathic, 2 secondary) with PAP were evaluated. To serve as controls, the smears of 11 normal subjects and 128 patients with other pulmonary disorders were also examined. The findings on the presence and number of globules were recorded. To differentiate PAP from other pulmonary disorders, the highest globule value obtained from the control group was chosen as the cutoff point. RESULTS The characteristic globules were not found in normal subjects and only found in 6 of 128 patients with other pulmonary disorders. Their clinical diagnoses were Sjögren syndrome in 2 cases; polymyositis, idiopathic pulmonary fibrosis, asbestosis, and hypersensitivity pneumonitis in 1 case each. The numbers of globules in these 6 patients were 1, 3, 17, 7, 3, and 2. In contrast, more than 100 globules were found in all patients with PAP. The number of globules was highly sensitive and specific in aiding a diagnosis of PAP when the cutoff value was set at 18. CONCLUSION The globules seen in Papanicolaou-stained smears of bronchoalveolar lavage fluid may be valuable in aiding a diagnosis of PAP, especially when the number of globules is more than 18.
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Wang JT, Chang SC, Ko WJ, Chang YY, Chen ML, Pan HJ, Luh KT. A hospital-acquired outbreak of methicillin-resistant Staphylococcus aureus infection initiated by a surgeon carrier. J Hosp Infect 2001; 47:104-9. [PMID: 11170773 DOI: 10.1053/jhin.2000.0878] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) has become an important hospital-acquired pathogen, infection with which often leads to major morbidity and mortality. The principal mode of transmission for MRSA is transfer of the organism from a carrier or infected patient to uninfected patients by the hands or clothing of staff. From January 16 1997 to April 2 1997, five patients who had undergone open-heart surgery in a hospital located in northern Taiwan, developed surgical wound infections and mediastinitis caused by MRSA. All patients were hospitalized in two adjacent surgical intensive care units (ICUs) following their respective operations. Consequently, the hospital's infection control team commenced investigation of the outbreak. Pulsed-field gel electrophoresis (PFGE) has been shown to be a good technique for epidemiological typing. By analysing cultures taken from staff by PFGE, it was demonstrated that this outbreak was most likely to be initiated by a surgeon with MRSA carriage. After elimination of the carrier state using topical mupirocin treatment, the outbreak was controlled without further incident.
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Wang JT, Fang CT, Chen YC, Chang SC. Necessity of a loading dose when using vancomycin in critically ill patients. J Antimicrob Chemother 2001; 47:246. [PMID: 11157921 DOI: 10.1093/jac/47.2.246] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Kuo YC, Tsai WJ, Wang JY, Chang SC, Lin CY, Shiao MS. Regulation of bronchoalveolar lavage fluids cell function by the immunomodulatory agents from Cordyceps sinensis. Life Sci 2001; 68:1067-82. [PMID: 11212870 DOI: 10.1016/s0024-3205(00)01011-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cordyceps sinensis (C. sinensis) is one of the well known fungi used in traditional Chinese medicine for treatment asthma and bronchial and lung inflammation. In this study, effects of C. sinensis methanolic extracts on bronchoalveolar lavage fluids (BALF) cells proliferation, inflammatory cytokines production, and genes expression were evaluated. The proliferative response of BALF cells to lipopolysaccharide (LPS) was determined by the tritiated thymidine uptake method. The cell-free supernatants were harvested then tested for interlukin-1beta (IL-1beta), interlukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8), interleukin-10 (IL-10), interleukin-12 (IL-12), and interferon-gamma (IFN-gamma) by the enzyme immunoassay. The results indicated that the CS-19-22 fraction dose dependently suppressed BALF cells proliferation activated by LPS. The CS-19-22 fraction also reduced IL-1beta, IL-6, IL-8, IL-10 and TNF-alpha production in LPS activated BALF cell cultures. Furthermore, the IL-12 and IFN-gamma production in activated BALF cells were enhanced by CS-19-22 treatment. The CS-19-22 fraction did not affect IL-1beta, IL-6, TNF-alpha, and IL-8 mRNAs expression in BALF cells detected by reverse transcription-polymerase chain reaction (RT-PCR). By contrast, the CS-19-22 fraction increased IL-12 and IFN-gamma mRNAs expression and decreased IL-10 mRNA expression in the BALF cells activated with LPS. These results indicated the CS-19-22 fraction suppressed IL-1beta, IL-6, TNF-alpha, and IL-8 cytokines production in BALF cells through other than inhibition of mRNAs expression pathway. These results also demonstrate that the therapeutic activity of C. sinensis in Chinese medicine may be related to modulation of TH1 and TH2 cells functions in bronchial airway.
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