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Ku SC, Hsueh PR, Yang PC, Luh KT. Clinical and microbiological characteristics of bacteremia caused by Acinetobacter lwoffii. Eur J Clin Microbiol Infect Dis 2000; 19:501-5. [PMID: 10968320 DOI: 10.1007/s100960000315] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A retrospective study was conducted to analyze the clinical features and pathogenic roles of bacteremia caused by Acinetobacter lwoffii during a 4-year period. Acinetobacter lwoffii (formerly Acinetobacter calcoaceticus var. lwoffii) is recognized as normal flora of the skin, oropharynx and perineum of healthy individuals. There are few reports of Acinetobacter lwoffii bacteremia associated with indwelling catheters in humans, particularly in immunocompromised hosts. The records of 18 patients with Acinetobacter lwoffii bacteremia whose underlying conditions included cancer (11 patients), systemic lupus erythematosus (n=1), chronic obstructive pulmonary disease (n = 2) and other diseases (n = 4), all but one of whom had indwelling catheters during the bacteremic episode, were examined. The clinical syndromes were classified as probable catheter-related bacteremia (n = 14), definite catheter-related bacteremia (n = 2), primary bacteremia (n = 1) or biliary tract infection (n = 1). The infections improved after removal of the catheter and/or appropriate antimicrobial therapy. One death was attributable to the bacteremic event. The results of this study show that indwelling catheter-related Acinetobacter lwoffii bacteremia in immunocompromised hosts appears to be associated with a low risk of mortality.
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Benjamin MA, McKay DM, Yang PC, Cameron H, Perdue MH. Glucagon-like peptide-2 enhances intestinal epithelial barrier function of both transcellular and paracellular pathways in the mouse. Gut 2000; 47:112-9. [PMID: 10861272 PMCID: PMC1727982 DOI: 10.1136/gut.47.1.112] [Citation(s) in RCA: 186] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Glucagon-like peptide-2 (GLP-2) is a recently identified potent intestinotrophic factor. We have evaluated the effect of GLP-2 treatment on intestinal epithelial barrier function in mice. METHODS CD-1 mice were injected subcutaneously with GLP-2 or a protease resistant analogue, h[Gly(2)]GLP-2, twice daily for up to 10 days. Saline injected mice served as controls. Jejunal segments were mounted in Ussing chambers. Tissue conductance was measured and unidirectional fluxes were determined for (i) Na(+) and the small inert probe Cr-EDTA (both transported via the paracellular pathway) and (ii) the macromolecule horseradish peroxidase (HRP, transported via the transcellular pathway). RESULTS Mice treated with GLP-2 or h[Gly(2)]GLP-2 for 10 days demonstrated significantly reduced intestinal conductance and fluxes of Na(+), Cr-EDTA, and HRP. Electron microscopy confirmed that GLP-2 reduced endocytic uptake of HRP into enterocytes. Functional changes (evident by four hours) preceded morphological changes (evident by 48 hours). CONCLUSIONS GLP-2 enhances intestinal epithelial barrier function by affecting both paracellular and transcellular pathways and thus may be of therapeutic value in a number of gastrointestinal conditions.
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Yang PC, Liu T, Wang CS, Zhang NZ, Tao ZD. Active ion secretion and permeability of rabbit maxillary sinus epithelium, impact of staphylococcal enterotoxin B. Otolaryngol Head Neck Surg 2000; 123:120-3. [PMID: 10889494 DOI: 10.1067/mhn.2000.102808] [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: 11/22/2022]
Abstract
The aim of this study was to investigate the impact of staphylococcal enterotoxin B (SEB), a model superantigen, on the physiologic functions of rabbit maxillary sinus epithelium. Rabbit sinus mucosae were separated under a surgical microscope and mounted in Ussing chambers to record short-circuit current, conductance, and permeability to horseradish peroxidase. The results showed that SEB evoked increases in sinus epithelial cell baseline short-circuit current, conductance, and permeability to horseradish peroxidase. When tumor necrosis factor-alpha (TNF-alpha) was added to the Ussing chambers, we got results similar to those obtained by SEB stimulation in vitro; the effects of SEB on sinus epithelial cells could be blocked by pretreatment with anti-TNF-alpha antibody. These results demonstrate that SEB is able to alter the function of sinus epithelial cells and to affect the capability of the epithelial defensive barrier, which may be mediated by TNF-alpha.
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Chang CH, Kuo PH, Hsu CH, Yang PC. Persistent severe hypocapnia and alkalemia in a 40-year-old woman. Chest 2000; 118:242-5. [PMID: 10893387 DOI: 10.1378/chest.118.1.242] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Wang DY, Yang PC, Yu WL, Kuo SH, Hsu NY. Serial antinuclear antibodies titre in pleural and pericardial fluid. Eur Respir J 2000; 15:1106-10. [PMID: 10885431 DOI: 10.1034/j.1399-3003.2000.01520.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The antinuclear antibodies (ANA) test has been a cornerstone of the evaluation of connective tissue disease. The aim of this study was to investigate the diagnostic value of the ANA test in pleural or pericardial effusions of unknown causes. Over a 3-yr period, a total of 126 pleural fluid and 30 pericardial fluid samples were analysed. ANA tests were performed using a commercially available kit. The ANA kit used an indirect immunofluorescent antibody method with a human epithelial (HEP-2) cell line as substrate. Patients with high fluid ANA titre (>1:160) received a second aspiration 2 weeks after the initial aspiration if diagnosis was not confirmed. ANA results were positive in 39 pleural and 10 pericardial fluid samples. All but one of the effusions with positive ANA testing were exudative. Eleven pleural or pericardial effusions due to active systematic lupus erythematosus were identified and all had high ANA titres (1:160) with various staining patterns. Thirty-eight of 145 patients (26%) with effusions of nonlupus aetiologies had positive ANA testing in pleural or pericardial fluid. Thirteen of these 38 patients had high ANA titre. Malignant or paramalignant effusions constituted 11 of the 13 samples. In conclusion, although a negative antinuclear antibodies test makes a diagnosis of lupus serositis unlikely, high antinuclear antibodies titres in pleural or pericardial fluid are not diagnostic of lupus serositis even when as high as 1:5,120. An unexplained high antinuclear antibodies titre in pleural or pericardial effusion warrants search for malignancy.
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Hsueh PR, Teng LJ, Chen YC, Yang PC, Ho SW, Luh KT. Recurrent bacteremic peritonitis caused by Enterococcus cecorum in a patient with liver cirrhosis. J Clin Microbiol 2000; 38:2450-2. [PMID: 10835030 PMCID: PMC86842 DOI: 10.1128/jcm.38.6.2450-2452.2000] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterococcus cecorum (formerly Streptococcus cecorum), originally isolated from poultry intestines, has rarely been encountered in human diseases. A 60-year-old man with liver cirrhosis and hepatocellular carcinoma developed peritonitis on the seventh day of his hospitalization. Cultures of one blood sample and one ascites fluid sample obtained on that day both grew E. cecorum. The patient received intravenous cefoxitin therapy and initially responded well. Unfortunately, another episode of peritonitis associated with septic shock developed 24 days after the start of treatment, and culture of one blood specimen yielded the same organism. The isolates were identified by the conventional biochemical tests, the API Rapid ID 32 Strep system, and the API ZYM system (both systems from bioMerieux, Marcy L'Etoile, France) and were further confirmed by cellular fatty acid chromatography and 16S rRNA gene partial sequencing. The identical biotype, antibiotype, and random amplified polymorphic DNA pattern of the three isolates documented the long-term persistence of this organism in the patient. To the best of our knowledge, this is the first clinical description of recurrent bacteremic peritonitis caused by E. cecorum.
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Chen KY, Hsueh PR, Liaw YS, Yang PC, Luh KT. A 10-year experience with bacteriology of acute thoracic empyema: emphasis on Klebsiella pneumoniae in patients with diabetes mellitus. Chest 2000; 117:1685-9. [PMID: 10858403 DOI: 10.1378/chest.117.6.1685] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES To provide an updated evaluation of the bacteriology of acute thoracic empyema for more efficacious treatment. DESIGN : The medical and microbiological records of all patients who received a diagnosis of acute thoracic empyema were reviewed. Based on the bacteria isolated from the pleural fluid, the patients were classified into the following four groups: aerobic or facultative Gram-positive; aerobic Gram-negative; anaerobic; and mixed. SETTING A university-affiliated tertiary medical center. PATIENTS AND METHODS From January 1989 to December 1998, 171 patients with a diagnosis of acute thoracic empyema were treated. A comparative analysis of the isolates from pleural effusions, the mean length of hospital stay, the mean duration of chest tube drainage, the mean duration between the onset of symptoms and the establishment of diagnosis, treatment efficacy, and the need for subsequent intervention was performed. RESULTS A total of 163 microorganisms were isolated from the pleural fluid of 139 patients. These patients were classified according to the following types of isolates: aerobic or facultative Gram-positive (n = 47); aerobic Gram-negative (n = 59); anaerobic (n = 14); and mixed (n = 19). Klebsiella pneumoniae was the most commonly isolated pathogen (24. 4%) and was strongly associated with a diagnosis of diabetes mellitus. The mortality rate of patients with aerobic Gram-negative bacilli isolated was the highest (22.0%), followed by those with mixed pathogens isolated (15.7%), aerobic or facultative Gram-positive (6.4%), and anaerobic (0%). CONCLUSIONS The increasing incidence of acute thoracic empyema caused by Gram-negative bacilli, especially by K pneumoniae, has become an increasing problem. The isolation of aerobic Gram-negative bacilli or multiple pathogens from pleural fluid is associated with a poor prognosis and indicates a need for more aggressive antimicrobial chemotherapy.
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83
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Tsai CP, Pan CH, Liu MY, Lin YL, Chen CM, Huang TS, Cheng IC, Jong MH, Yang PC. Molecular epidemiological studies on foot-and-mouth disease type O Taiwan viruses from the 1997 epidemic. Vet Microbiol 2000; 74:207-16. [PMID: 10808089 DOI: 10.1016/s0378-1135(00)00182-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Sequence diversity was assessed of the complete VP1 gene directly amplified from 49 clinical specimens during an explosive foot-and-mouth disease (FMD) outbreak in Taiwan. Type O Taiwan FMD viruses are genetically highly homogenous, as seen by the minute divergence of 0.2-0.9% revealed in 20 variants. The O/HCP-0314/TW/97 and O/TCP-022/TW/97 viral variants dominated FMD outbreaks and were prevalent in most affected pig-raising areas. Comparison of deduced amino acid sequences around the main neutralizable antigenic sites on the VP1 polypeptide showed no significant antigenic variation. However, the O/CHP-158/TW/97 variant had an alternative critical residue at position 43 in antigenic site 3, which may be due to selective pressure in the field. Two vaccine production strains (O1/Manisa/Turkey/69 and O1/Campos/Brazil/71) probably provide partial heterologous protection of swine against O Taiwan viruses. The type O Taiwan variants clustered in sublineage A1 of four main lineages in the phylogenetic tree. The O/Hong Kong/9/94 and O/1685/Moscow/Russia/95 viruses in sublineage A2 are closely related to the O Taiwan variants. The causative agent for the 1997 epidemic presumably originated from a single common source of type O FMD viruses prevalent in neighboring areas.
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Abstract
STUDY OBJECTIVES To analyze the clinical spectra, pathogenesis, treatment, outcome, and prognostic factors of fungal empyema thoracis. DESIGN The medical records of patients with positive fungal cultures from pleural effusions were retrospectively analyzed. SETTING A university-based tertiary care hospital in Taipei, Taiwan. PATIENTS AND METHODS From January 1990 through December 1997, patients diagnosed with fungal empyema were included in this study. The criteria for diagnosis of fungal empyema thoracis were as follows: (1) isolation of a fungal species from the pleural effusion; (2) significant signs of infection, such as fever (body temperature > 38.3 degrees C) and leukocytosis (white blood cell > 10,000/microL); and (3) isolation of the same mold species from pleural effusion on more than one occasion, or from pleural effusion and other specimens such as blood, sputum, or surgical wounds that showed evidence of tissue invasion. RESULTS Sixty-seven patients with fungal empyema thoracis were included. Their mean age was 54 years (range, 2 weeks to 93 years), and 64% (43 patients) were men. Fifty-seven patients (85%) had various underlying diseases, and 18 (27%) had more than one immunocompromising condition. A total of 73 fungal isolates were recovered from pleural effusion; the most commonly encountered were Candida species (47 isolates, 64%), Torulopsis glabrata (13 isolates, 18%), and Aspergillus species (9 isolates, 12%). Candida albicans (28 isolates) was the most common Candida species, followed by Candida tropicalis (13 isolates). Six patients (9%) had two fungal strains isolated, and 16 (24%) had concomitant bacterial empyema thoracis. Eighteen patients (27%) had concurrent fungemia. Most (56 patients, 84%) cases of fungal empyema thoracis were nosocomial, and many case (43 patients, 64%) were acquired in ICUs. Abdominal disease (20 patients, 30%), especially previous abdominal surgery and GI perforation (12% and 10%, respectively), was the most common cause of fungal empyema thoracis, followed by bronchopulmonary infection (15 patients, 22%) and chest surgery (12 patients, 18%). Forty-nine patients (73%) received systemic antifungal therapy, and 38 (57%) underwent closed drainage therapy. Eleven patients (16%) underwent pleural irrigation with normal saline solution, povidone-iodine solution, or antifungal agents. Six patients (9%) finally received decortication. All patients receiving surgery or pleural irrigation with antifungal agents survived. Despite the aforementioned management, the crude mortality was high (73%). Multivariate analysis showed a significantly increased risk of death in immunocompromised patients (relative risk, 1.58; p < 0.005) and those with respiratory failure (relative risk, 2.31; p < 0.001). Systemic antifungal therapy was associated with a significantly lower risk of death (relative risk, 0.69; p < 0.05). CONCLUSION These data imply an increasing incidence of fungal empyema thoracis in recent years and the necessity for aggressive treatment of patients with this disease.
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Santos J, Benjamin M, Yang PC, Prior T, Perdue MH. Chronic stress impairs rat growth and jejunal epithelial barrier function: role of mast cells. Am J Physiol Gastrointest Liver Physiol 2000; 278:G847-54. [PMID: 10859213 DOI: 10.1152/ajpgi.2000.278.6.g847] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We examined the impact of chronic stress on rat growth rate and intestinal epithelial physiology and the role of mast cells in these responses. Mast cell-deficient (Ws/Ws) rats and +/+ littermate controls were submitted to water avoidance stress or sham stress, 1 h/day, for 5 days. Seven hours after the last sham or stress session, jejunal segments were mounted in Ussing chambers, in which secretion and permeability were measured. Body weight (as a growth index) and food intake were determined daily. Stress increased baseline jejunal epithelial ion secretion (indicated by short-circuit current), ionic permeability (conductance), and macromolecular permeability (horseradish peroxidase flux) in +/+ rats, but not in Ws/Ws rats, compared with nonstressed controls. Stress induced weight loss and reduced food intake similarly in the groups. In +/+ rats, these parameters remained altered 24-72 h after the cessation of stress. Modulation of stress-induced mucosal mast cell activation may help in the management of certain intestinal conditions involving epithelial pathophysiology.
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Hsueh PR, Teng LJ, Hung CC, Hsu JH, Yang PC, Ho SW, Luh KT. Molecular evidence for strain dissemination of Penicillium marneffei: an emerging pathogen in Taiwan. J Infect Dis 2000; 181:1706-12. [PMID: 10823772 DOI: 10.1086/315432] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/1999] [Revised: 01/24/2000] [Indexed: 11/03/2022] Open
Abstract
From January 1987 through December 1998, Penicillium marneffei infection (23 patients) or colonization (1 patient) was diagnosed in a total of 24 patients in Taiwan. Of these 24 patients, 16 (67%) had AIDS and 20 (83%) had disseminated P. marneffei infection. The majority (63%) of the infections were considered indigenous. The number of cases has increased markedly in recent years, with 17 of the 24 cases diagnosed from 1996 through 1998. Twenty preserved isolates of P. marneffei, recovered from 11 patients treated at National Taiwan University Hospital during the period of January 1996 through December 1998, were studied to determine the epidemiology of P. marneffei infections. Among the 20 isolates, a total of 8 strains (highly related isolates) were identified on the basis of tests for susceptibility to 5 antifungal agents, for chromosomal DNA restriction fragment-length polymorphism types, and for randomly amplified polymorphic DNA patterns. One of the strains (6 isolates) was isolated from 4 patients treated in 1997 and 1998. Strain spreading of P. marneffei may partially contribute to the increased number of infections caused by this organism in immunosuppressed patients in Taiwan.
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87
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Wang DY, Yang PC, Yu WL, Shiah DC, Kuo HW, Hsu NY. Comparison of different diagnostic methods for lupus pleuritis and pericarditis: a prospective three-year study. J Formos Med Assoc 2000; 99:375-80. [PMID: 10870326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND AND PURPOSE Pleural or pericardial effusions, or both, are commonly encountered, but the differential diagnosis is sometimes difficult. We evaluated the diagnostic value of effusion immunofluorescent antinuclear antibody (ANA) titer, systemic lupus erythematosus (SLE) latex agglutination slide test, and cytologic LE cell examination in patients with pleural and/or pericardial effusions of various etiologies. METHODS A total of 153 pleural and/or pericardial effusion specimens were collected by aspiration from 152 patients (14 SLE and 138 non-SLE patients). All specimens were sent for routine biochemistry testing, determination of ANA titer, SLE latex agglutination slide test, and LE cell examination. RESULTS Ten of the 14 SLE patients had lupus serositis and all of them had high ANA titers (> or = 1:160) in their effusions. SLE latex and LE cell tests were positive in seven and eight patients with lupus serositis, respectively. The remaining four SLE patients with effusion of etiologies other than lupus serositis had low or negative effusion ANA titers. Among the non-SLE patients, 29 of 112 patients (26%) with pleural effusion and six of 26 patients (23%) with pericardial effusion had positive ANA tests (> or = 1:40). None of them had a positive SLE latex or LE cell test result. Thirteen of the 138 non-SLE patients (11%) had high effusion ANA titers (> or = 1:160). Effusion in 11 of 13 non-SLE patients (85%) was due to malignancy. CONCLUSIONS Effusion ANA titer detection is a very sensitive but nonspecific test for the diagnosis of lupus serositis. SLE latex and cytologic LE cell tests can aid in the differential diagnosis as complementary tools. The specificity, positive and negative predictive values of these two tests are excellent for the diagnosis of lupus serositis.
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Liao WY, Liaw YS, Wang HC, Chen KY, Luh KT, Yang PC. Bacteriology of infected cavitating lung tumor. Am J Respir Crit Care Med 2000; 161:1750-3. [PMID: 10806182 DOI: 10.1164/ajrccm.161.5.9905103] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Differentiation between in situ infection and simple tumor necrosis in cavitating lung tumors by means of imaging studies is difficult. In this study, we prospectively investigated the role of ultrasound (US)-guided transthoracic aspiration for bacteriologic examination of infected cavitating lung tumors, and the influence of the culture results on the treatment of patients. Twenty-two patients (18 men and four women) with cavitating lung tumors treated from January 1996 to October 1998 were included. All patients underwent US-guided transthoracic aspiration for bacterial, fungal, and mycobacterial cultures. Microorganisms were isolated from six of seven febrile patients and one of 15 nonfebrile patients. A total of nine pathogens were isolated from seven patients: Klebsiella pneumoniae (n = 3); Haemophilus influenzae (n = 2); Enterococcus faecium (n = 1); Bifidobacterium (n = 1); Shewanella putrefaciens (n = 1); and Mycobacterium tuberculosis (n = 1). Two pathogens were isolated from the aspirate cultures in two patients, while the others had monomicrobial infection. The six febrile patients who had positive lung aspirate cultures were treated with empiric antimicrobial agents before the culture results were available, and the culture results led to adjustment of the antibiotic regimen in five of these. The clinical conditions of the six patients with infected cavitating lung tumors improved after the initiation of individualized antimicrobial treatment. Pneumothorax occurred in one patient, and was the sole procedure-related complication. In conclusion, US-guided transthoracic aspiration is helpful for differentiating infected cavitating lung tumors from simple tumor necrosis. Infection in cavitating lung tumors is common among febrile patients, and the culture results can guide modification of the antimicrobial therapy.
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Wang HC, Zentner MD, Deng HT, Kim KJ, Wu R, Yang PC, Ann DK. Oxidative stress disrupts glucocorticoid hormone-dependent transcription of the amiloride-sensitive epithelial sodium channel alpha-subunit in lung epithelial cells through ERK-dependent and thioredoxin-sensitive pathways. J Biol Chem 2000; 275:8600-9. [PMID: 10722699 DOI: 10.1074/jbc.275.12.8600] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The amiloride-sensitive epithelial Na(+) channel (ENaC) plays a critical role in the maintenance of alveolar fluid balance. It is generally accepted that reactive oxygen and nitrogen species can inhibit ENaC activity and aggravate acute lung injury; however, the molecular mechanism for free radical-mediated ENaC inhibition is unclear. Previously, we showed that the expression of the alpha-subunit of ENaC, alpha-ENaC, which is indispensable for ENaC activity, is repressed by Ras activation in salivary epithelial cells. Here, we investigated whether exogenous H(2)O(2) modulates alpha-ENaC gene expression in lung epithelial cells through a similar molecular mechanism. Utilizing transient transfection reporter assays and site-directed mutagenesis analyses, we found that the glucocorticoid response element (GRE), located at -1334 to -1306 base pairs of the alpha-ENaC 5'-flanking region, is the major enhancer for the stimulated alpha-ENaC expression in A549 lung epithelial cells. We further demonstrate that the presence of an intact GRE is necessary and sufficient for oxidants to repress alpha-ENaC expression. Consistent with our hypothesis, exogenous H(2)O(2)-mediated repression of alpha-ENaC GRE activity is partially blocked by either a specific inhibitor for extracellular signal-regulated kinase (ERK) pathway activation, U0126, or dominant negative ERK, suggesting that, in part, activated ERK may mediate the repressive effects of H(2)O(2) on alpha-ENaC expression. In addition, overexpression of thioredoxin restored glucocorticoid receptor action on the alpha-ENaC GRE in the presence of exogenous H(2)O(2). Taken together, we hypothesize that oxidative stress impairs Na(+) transport activity by inhibiting dexamethasone-dependent alpha-ENaC GRE activation via both ERK-dependent and thioredoxin-sensitive pathways. These results suggest a putative mechanism whereby cellular redox potentials modulate the glucocorticoid receptor/dexamethasone effect on alpha-ENaC expression in lung and other tight epithelia.
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Huang SY, Kuo YH, Tsou HL, Lee YP, King YT, Huang HC, Yang PC, Lee WC. The decline of porcine sperm motility by geldanamycin, a specific inhibitor of heat-shock protein 90 (HSP90). Theriogenology 2000; 53:1177-84. [PMID: 10798494 DOI: 10.1016/s0093-691x(00)00262-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sperm motility is an important parameter for fertility. The molecular mechanisms of mammalian sperm motility are still largely undefined. Our previous observations suggested that heat shock protein 90 (HSP90) may be associated with porcine sperm motility. The aim of the present study was to further characterize the plausible novel function of HSP90 on sperm motility. Semen from normal, sexually mature boars with sperm motility higher than 80% was used. An HSP90-specific inhibitor, geldanamycin (GA), was added to diluted semen at 0.5, 1.0, 2.5 or 5.0 microg/mL and the semen was then incubated at 37 degrees C for 15, 30, 45 or 60 min. Sperm motility was determined by using computer-assisted semen analyzer at the end of incubation. The results indicated that GA significantly reduced sperm motility in a dose and time dependent manner. Moreover, incubation of semen with 5.0 microg/mL GA for 15 min completely stopped sperm motility. To test the reversibility of the GA effect on sperm motility, GA was removed after 30 min incubation and was replaced with fresh extender alone or with extender plus 5 mM caffeine, then incubated for another 15, 30, 45 or 60 min. The results showed that simply removing GA did not reverse the inhibitory effect on sperm motility, while adding caffeine partially reversed this inhibitory effect. However, the effect of 2.5 or 5.0 microg/mL GA was not reversed by caffeine. Considering the specificity of GA targeting to HSP90, the above observations suggested that HSP90 may play a crucial role in regulating porcine sperm motility.
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91
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Abstract
Recent studies have confirmed that US is a very useful diagnostic tool for various diseases of the chest. The image information provided by US is helpful for etiologic diagnosis and clinical management. US-guided needle biopsy provides a precise and safe approach for transthoracic tissue sampling of lesions. The diagnostic yield is high, and the procedure is relatively easy and very safe. Color Doppler US and amplitude US angiography further extend the diagnostic potential and safety of this invasive procedure. Vascular information can be obtained and the needle shaft can be visualized clearly while conducting a biopsy. US examination and US-guided needle aspiration biopsy have now become indispensable diagnostic tools for various chest diseases.
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Yuan A, Yang PC, Lee L, Wu HD, Kuo SH, Luh KT, Chen WJ, Lin FY. Reactive pulmonary artery vasoconstriction in pulmonary consolidation evaluated by color Doppler ultrasonography. ULTRASOUND IN MEDICINE & BIOLOGY 2000; 26:49-56. [PMID: 10687792 DOI: 10.1016/s0301-5629(99)00118-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A total of 122 patients with pulmonary consolidation on chest radiographs underwent color Doppler ultrasonography to evaluate hemodynamic change in regional pulmonary artery in pulmonary consolidation due to various causes. The diseases underlying pulmonary consolidation included 66 simple pneumonia, 37 obstructive pneumonia, 13 tumor consolidation and 6 pulmonary infarctions. Blood flow signals in consolidation were detected by color-flow mapping. The degree of reactive vasoconstriction was evaluated from analysis of the spectral waveform of the blood flow in the segmental pulmonary artery by several vessel resistance-indicating Doppler ultrasound (US) indices, including pulsativity index (PI), resistive index (RI), and acceleration time (AT). The results showed that reactive vasoconstriction was most marked in obstructive pneumonia, followed by simple pneumonia, and least in tumor consolidation (p < 0.001, Kruskal-Wallis test and p < 0.001, Dunn's test for comparison of PI, RI and AT values between different groups of pulmonary consolidation). No flow was detected in pulmonary infarction. We conclude that color Doppler US is a useful tool for evaluating reactive vasoconstriction in pulmonary consolidation. The different degrees of reactive vasoconstriction may be helpful in exploring the possible etiology of pulmonary consolidation.
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Wu TT, Hsueh PR, Lee LN, Yang PC, Luh KT. Pneumonia caused by penicillin-nonsusceptible Streptococcus pneumoniae: clinical characteristics, prognostic factors, and outcomes. J Formos Med Assoc 2000; 99:18-23. [PMID: 10743342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
BACKGROUND AND PURPOSE Pneumococcal pneumonia caused by penicillin-nonsusceptible Streptococcus pneumoniae (PNSSP) is increasing worldwide. To better understand this infection, patients with pneumococcal pneumonia treated at National Taiwan University Hospital during a 5-year period were evaluated to determine the clinical characteristics, prognostic factors, and outcomes of the infection. METHODS Eighty-one patients with 81 episodes of pneumococcal pneumonia diagnosed from January 1993 to December 1997 were analyzed retrospectively. Patients were categorized into two groups according to susceptibility results. Differences between groups were evaluated with Student's t-test and the chi-square test. Univariate analysis was used to identify factors associated with mortality. RESULTS Infections were caused by penicillin-susceptible S. pneumoniae (PSSP) in 57 (70%) patients and by PNSSP in the remaining 24 (30%). Nosocomial acquisition was more common in PNSSP (25%) than in PSSP patients (10%) (p = 0.05), while the frequency of bacteremia (54% vs 60%) and the mortality rate (46% vs 32%) did not differ significantly between the PNSSP and PSSP groups. Among the 24 patients with pneumonia caused by PNSSP, those 65 years of age or older had a lower incidence of bacteremia (4/14, 29%) than those who were younger (9/10, 90%) (p = 0.03). In patients with pneumonia caused by PNSSP, the outcome was not significantly related to the treatment regimen (penicillin vs nonpenicillin beta-lactam antibiotics or vancomycin, 33% vs 47%; p = 0.4). The only factors associated with mortality from these infections were shock (p = 0.003) and multilobar consolidation (p = 0.01) at the time of admission. CONCLUSIONS These data suggest that the clinical outcome of pneumococcal pneumonia is more closely related to the clinical condition at presentation than the susceptibility status of the pneumococcus.
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Yang PC, Chu RM, Chung WB, Sung HT. Epidemiological characteristics and financial costs of the 1997 foot-and-mouth disease epidemic in Taiwan. Vet Rec 1999; 145:731-4. [PMID: 10972111 DOI: 10.1136/vr.145.25.731] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Between March and July 1997, a devastating outbreak of foot-and-mouth disease (FMD), serotype O, occurred in pigs in Taiwan. A total of 6,147 pig farms with more than 4 million pigs were infected, and 37.7 per cent of the pigs in Taiwan either died (0.18 million pigs) or were killed (3.85 million pigs). The epidemic reached its peak during the fifth week after it was first recognised. During the eighth and ninth weeks, a two-dose blanket vaccination programme was instituted which led to a large reduction in new outbreaks. Except for two cities, the whole of Taiwan was declared an FMD-infected zone. During the four months in which new farm outbreaks occurred, 21.7 per cent of the pigs on infected farms showed clinical signs, and there was an overall mortality of 3.95 per cent. During the early stages of the epidemic, the incubation period was as short as 24 hours and the case fatality rates for suckling piglets reached 100 per cent. The financial cost of the epidemic was estimated at US$ 378.6 million, including indemnities, vaccines, carcase disposal plus environmental protection, miscellaneous expenses, and loss of market value. Owing to the ban on exports of pork to Japan, it is estimated that the total economic cost to Taiwan's pig industry will be about US$ 1.6 billion.
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95
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Ku SC, Yu CJ, Chang YL, Yang PC. Disseminated cytomegalovirus disease in a patient with systemic lupus erythematosus not undergoing immunosuppressive therapy. J Formos Med Assoc 1999; 98:855-8. [PMID: 10634027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
We describe a case of cytomegalovirus (CMV) infection in a 25-year-old woman with a 3-year history of systemic lupus erythematosus (SLE) with persistently high disease activity, who had not received immunosuppressive therapy. Disseminated CMV infection presented with upper gastrointestinal bleeding, high fever, respiratory distress, leukopenia, and thrombocytopenia. The CMV infection was successfully treated with combined antiviral and immunoglobulin therapy, and the SLE activity decreased concomitantly. CMV disease is closely related to host immunosuppression, primarily T-lymphocyte dysfunction. This case should highlight the relationship between clinically significant CMV disease and compromised immunity in patients with active SLE who are not receiving immunosuppressive therapy.
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96
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Yang PC. Impact of modern technology on the advancement of medicine. J Formos Med Assoc 1999; 98:717. [PMID: 10705685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
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97
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Grant RF, Black TA, den Hartog G, Berry JA, Neumann HH, Blanken PD, Yang PC, Russell C, Nalder IA. Diurnal and annual exchanges of mass and energy between an aspen-hazelnut forest and the atmosphere: Testing the mathematical model Ecosys with data from the BOREAS experiment. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998jd200117] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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98
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Yang PC, Black TA, Neumann HH, Novak MD, Blanken PD. Spatial and temporal variability of CO2concentration and flux in a boreal aspen forest. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999jd900295] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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99
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Wu TT, Wang HC, Yang PC, Kuo SH, Luh KT. Pulmonary cryptococcosis: manifestations in the era of acquired immunodeficiency syndrome. J Formos Med Assoc 1999; 98:621-6. [PMID: 10560238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
To examine the clinical manifestations, treatment, and outcome of pulmonary cryptococcosis, we reviewed the medical records of all patients treated for Cryptococcus neoformans infection at our hospital from January 1988 through September 1998. Sixty-three patients were included in the analysis, 10 (16%) of whom had acquired immunodeficiency syndrome (AIDS). Thirty-four of the 53 non-AIDS patients, including 19 men and 15 women had pulmonary cryptococcosis, including 31 with isolated pulmonary cryptococcosis and three with disseminated disease. Of the 10 AIDS patients, seven presented with disseminated cryptococcosis (including one patient with lung involvement) and one had isolated cryptococcal lung disease. The age (mean +/- SD) of the 34 non-AIDS patients with pulmonary cryptococcosis was 52.1 +/- 15.2 years (range, 19-75 yr). Cough was the most common symptom (58%). Diabetes mellitus (12%) and malignancy (12%) were two major underlying diseases. Nodules and masses were the predominant manifestations of pulmonary cryptococcosis in non-AIDS patients (79%). The most frequently used diagnostic modality for pulmonary cryptococcosis was biopsy with/without aspiration under ultrasound guidance (56%). Antifungal therapy (20/34) was the most common treatment for non-AIDS patients, followed by surgical resections with antifungal therapy (9), surgical resections alone (3), and no treatment (2). Antifungal therapy and/or resection yielded excellent outcomes (total recovery, 27; improvement, 4). Of the 18 patients who underwent lumbar puncture, only two had positive cerebrospinal fluid (CSF) cultures for C. neoformans, both had symptoms and signs of increased intracranial pressure. There was no clinical evidence of meningitis in the other 32 patients. Our findings indicate that pulmonary cryptococcosis in non-AIDS patients tends to be a more localized and benign process than in AIDS patients. Ultrasound-guided lung biopsy or aspiration is an effective tool for diagnosis. CSF examination may not be mandatory as an initial routine procedure for pulmonary cryptococcosis in non-AIDS patients.
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Yang PC, Berin MC, Perdue MH. Enhanced antigen transport across rat tracheal epithelium induced by sensitization and mast cell activation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:2769-76. [PMID: 10453020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Ag challenge to the apical surface of tracheal epithelium results in a rapid ion secretory response due to the activation of mast cells. The aim of this study was to examine the impact of sensitization and specific Ag challenge on the timing, route, and quantity of Ag transported across tracheal epithelium. After sensitization of rats to a model protein, HRP, tracheal tissues were excised and mounted in Ussing chambers. Tracheas from HRP-sensitized rats, but not naive or OVA-sensitized rats, responded to apical HRP challenge with a rise in short-circuit current (beginning at approximately 2 min). Photomicrographs of tissues fixed at 2 min showed that initial transepithelial HRP transport occurred via endosomes and was significantly enhanced in HRP-sensitized rats compared with both control groups. In addition, nonciliated cells, the proportion of which increased after sensitization, contained significantly more HRP than ciliated cells. The hypersensitivity response occurred only in HRP-sensitized and challenged rats and was associated with increased conductance of tracheal epithelium and overall flux of HRP across the tissue. This increased flux of Ag and elevated conductance was not observed in mast cell-deficient Ws/Ws rats. Photomicrographs of tissues fixed 90 min after challenge also showed HRP in the paracellular spaces between adjacent epithelial cells. We conclude that sensitization increases uptake of specific Ag initially via an endosomal transcellular pathway across tracheal epithelium and that, after the hypersensitivity reaction, mast cell-dependent recruitment of the paracellular pathway further augments Ag influx into airway tissue.
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