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Biomedical subjects

S Kohno

Publications and source records attributed to S Kohno.

At least 523 records · Page 29Linked to original sources

Expression of human T lymphotropic virus type 1 (HTLV-1) tax/rex gene in fresh bronchoalveolar lavage cells of HTLV-1-infected individuals.

Accumulating evidence has suggested the involvement of HTLV-1 in the inflammatory lesions of various organs, including the lung. However, the causal relationship between HTLV-1 and inflammatory responses in the organs remains to be elucidated. In order to evaluate the expression of HTLV-1 and its effects in the lung, we examined the expression of mRNA for the HTLV-1 tax/rex gene in fresh bronchoalveolar lavage cells (BALC) and peripheral blood mononuclear cells (PBMC) of 23 seropositive individuals, including six patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), by use of an improved method of reverse transcription-polymerase chain reaction (RT-PCR). The tax/rex mRNA was more frequently detected in BALC than in PBMC. All the HAM/TSP patients and eight of 17 carriers without neurological symptoms showed the expression of tax/rex mRNA in the BALC. IgM class antibodies to HTLV-1 were preferentially detected in sera of the tax/rex mRNA-positive individuals. The detection of tax/rex mRNA correlated closely with the presence of lymphocytosis accompanied by an elevated proportion of IL-2 receptor-bearing T cells in the BALC. Our findings indicate the crucial role of viral expression in the inflammatory response in the lung in HTLV-1-infected individuals.

Adolescent↗

Activation of macrophages and expansion of specific T lymphocytes in the lungs of mice intratracheally inoculated with Cryptococcus neoformans.

A quantitative and qualitative change in inflammatory cells in the lungs of mice after intratracheal inoculation of heat-killed Cryptococcus neoformans was examined by direct analysis of the pulmonary intraparenchymal leucocytes. Macrophages and T and B lymphocytes increased, peaked at day 7, and then gradually decreased to the basal level. Macrophages were activated 7 days after the inoculation, as indicated by the enhanced expression of MHC class II, intercellular adhesion molecule-1 (ICAM-1) and Fc receptor (FcR), which have been known as their activation markers. T cells were also activated, as indicated by the induction of IL-2 receptor (IL-2R) and the enhanced expression of leucocyte function-associated molecule-1 (LFA-1) and ICAM-1, a pair of adhesion molecules which have also been regarded as T cell activation markers. CD4+ T cells preferentially accumulated in lungs, and proliferated in vitro by stimulation with heat-killed whole yeast cells, suggesting that at least some of the infiltrated T cells expand locally in response to the organisms. These results demonstrate that the activation of macrophages and T cells reactive to C. neoformans is induced in lungs after intratracheal inoculation of heat-killed organisms, and suggest that these cells interact to eliminate organisms more efficiently from the host.

Animals↗

[Five cases of tsutsugamushi disease].

We experienced 5 cases of tsutusgamushi disease from October to November 1993 at Hokusyo Central Hospital. All patients showed high fever, skin rash and eschar and four patients showed lymph node swelling. All cases were diagnosed serologically by indirect-immunofluorescence technique and treated with minocycline. In a survey of anti-Karp, Kato, Gilliam, Kawasaki, Kuroki antibodies, all patients showed the highest antibody titers against the Kawasaki strain and they were considered Kawasaki type. In Nagasaki Prefecture, the number of patients with tsutsugamushi disease has been increasing since 1982. We carried out immunologic and epidemiologic studies about this disease in Nagasaki Prefecture.

Adult↗

Epidemiology studies of clinical isolates of Cryptococcus neoformans of Japan by restriction fragment length polymorphism.

Previous epidemiological studies of Cryptococcus neoformans infection in Japan showed that only C. neoformans var. neoformans is present and serotype A is the most common with frequencies in excess of 95%. A DNA fingerprinting method, using a genomic DNA probe (UT-4p), has become available recently which discriminates between individual isolates in a population that are morphologically and serologically indistinguishable. Fifty-two serotype A isolates of C. neoformans were obtained from three different institutions (in Nagasaki, Chiba, and Tokyo) in Japan. Only two of these strains were isolated from AIDS patients and one from pigeon excreta. Of the nine reported finger-printing patterns in serotype A, only three types (IV, V and VII) were observed in Japanese isolates. Pattern IV was almost exclusively observed in Nagasaki isolates (21/22) with only one of pattern VII. In Chiba, however, patterns VII and IV appeared to be equally distributed. In Tokyo, patterns IV and V (which included two isolates from AIDS patients) were observed at similar frequencies. Restriction fragment length polymorphism analysis of four isolates of serotype AD showed a typical serotype A pattern which also contained a serotype D-specific band. This finding suggests the independence of serotype AD. These data could enhance the survey of the epidemiology of cryptococcosis.

Cryptococcosis↗

[Three cases of Pasteurella multocida infection in the respiratory tract].

Pasteurella multocida (P. multocida) is well recognized as "normal flora" in the upper respiratory tract of cats, dogs and other animals. Recently, various infections due to P. multocida in human have been noted as pulmonary infections in the patients with chronic pulmonary diseases as well as skin abscesses or septicemia after an animal bite or scratch. We report here three cases of respiratory tract infections caused by P. multocida. The first two patients had acute exacerbation of bronchiectasis caused by P. multocida and the other patients with pulmonary emphysema developed pneumonia. These three patients improved by antibiotic therapy. In Japan, P. multocida respiratory tract infection is rare, but it may become more common in the future. Therefore, it seems to be important to take this pathogen into consideration in the management of chronic lung disease.

Adult↗

[A case of brain abscess associated with enterococcal endocarditis].

Enterococcal infections involving the central nervous system are uncommon clinical entities. A 74-year-old male was admitted to our hospital on November 3, 1991 for high fever. Nuchal rigidity was observed at neurological examination. All four blood cultures yielded E. faecalis. The MIC value of ABPC against the isolated E. faecalis was 0.25 microgram/ml. Vegetation on the mitral valve and mitral regurgitation were revealed by an echocardiogram. Enhanced CT scan showed low density area with ring enhancement in the right basal ganglia and a CSF examination suggested bacterial meningitis. He became better after ABPC 8 g/day was intravenously administered. Then the vegetation on the mitral valve and the brain abscess disappeared. He was discharged with no complications. We reported a rare case of brain abscess associated with enterococcal endocarditis.

Aged↗

[Roxithromycin treatment in patients with chronic lower respiratory tract disease--its clinical efficacy and effect on cytokine].

We demonstrated the efficacy of "long term" roxithromycin (RXM) treatment in 15 patients with chronic lower respiratory tract disease (11 with diffuse panbronchiolitis and 4 with sinobronchial syndrome). (1) Fourteen (93.3%) of the 15 patients showed improvement when assessed by the comprehensive improvement score, and they showed significant improvements in PaO2 (74.2 +/- 10.4 Torr to 84.3 +/- 10.9 Torr, p < 0.01), %VC (86.9 +/- 20.2% to 96.0 +/- 21.9%, p < 0.001) and FEV1 (1.81 +/- 0.87 L to 2.14 +/- 1.08 L, p < 0.01) after RXM treatment. (2) Neutrophils accumulated in the pre-RXM treatment bronchoalveolar lavage (BAL) fluid and decreased in BAL fluid of patients responding to RXM treatment (49.8 +/- 28.3% to 17.1 +/- 15.7%, p < 0.01). Additionally, the levels of interleukin 1 beta and interleukin 8 were significantly higher in BAL fluid of these patients than those in the healthy volunteers (p < 0.025, p < 0.01 respectively), and correlated with the neutrophil accumulation (r = 0.619, p < 0.05). These cytokines showed a decrease after RXM treatment. These results indicated that RXM acts by reducing pulmonary inflammation through reduction of neutrophil migration to inflammatory sites, and is effective on chronic lower respiratory tract disease.

Adult↗

[Anaerobic respiratory infection--evaluation of methods of obtaining specimens].

Anaerobic cultures were performed on various kinds of specimens obtained from 67 patients with respiratory infections. The infections consisted of 33 cases of pneumonia, 14 cases of lung abscess, 6 cases of pyothorax, 9 cases of chronic lower respiratory tract infection, and 5 cases of infection of pulmonary cyst. Specimens included bronchoscopic specimens obtained using a single tube or protected catheter brush (PCB), transtracheal aspirate, percutaneous lung aspirate, aspirate using a suction tube through the tracheostomy or intubation tube, and pleural fluid. Anaerobes were isolated in 80% of pyothorax, 43% of lung abscess, and 15% of pneumonia (42% of aspiration pneumonia), respectively. Anaerobes isolated frequently in respiratory infections included Prevotella spp., Fusobacterium spp., and Peptostreptococcus spp. In regard to the type of specimen, bronchial aspirate obtained by bronchoscopy was useful in examination of pneumonia, and was useful as percutaneous lung aspirate in examination of lung abscess. But there was discrepancy of culture results between specimens obtained by different methods in the same patient. To confirm anaerobes as pathogens in respiratory infections, it is necessary to select an appropriate method to obtain specimens and to interpret the culture results comprehensively.

Adult↗

[Clinical investigation of obstructive pneumonia with lung cancer].

Nineteen episodes (18 patients) of obstructive pneumonia occurring in 247 patients with lung cancer were clinically examined, and the following findings were obtained. 1) All 18 patients were male smokers, with an average of 64 years. 2) Body temperatures stood above 37 degrees C in 95% of the 19 episodes. Leukocytosis was detected in 41%, and neutrophilia was observed in 69%. CRP values were positive in all episodes. 3) The frequency of obstructive pneumonia according to the site of lung cancer was 13.2% in proximal tumors and 1.7% in peripheral tumors. Pathologically, the frequency was 5.2% in adenocarcinomas 7.6% in squamous cell carcinomas, 15.6% in small cell carcinomas and 9.1% in large cell carcinomas. Squamous cell carcinomas even in Stage I led to obstructive pneumonia at the rate of 13.0%. In contrast, higher frequency was observed in adenocarcinomas in Stage II or later and small cell carcinomas in Stage IIIB or later. 4) Obstructive pneumonia was detected at the time of discovery of lung cancer in 48% of the 18 patients, and during treatment and in the terminal stage in 26% respectively. 5) Chest X-ray examinations showed that 42% of the pneumonia cases were lobar pneumonia and 11% had pleural effusion. 6) In expectorated sputum, 50% of bacteria isolated were gram-negative, 10% were gram-positive and 40% were unknown. 7) Most of the bacteria isolated from expectorated sputum showed a good susceptibility to antimicrobial agents, but those proved clinically ineffective. 8) The prognosis of obstructive pneumonia was significantly affected by performance status and levels of total protein and choline-esterase.

Aged↗

Effects of antifungal agent combinations administered simultaneously and sequentially against Aspergillus fumigatus.

The in vitro effects of antifungal agent combinations administered simultaneously and sequentially against 15 strains of Aspergillus fumigatus were tested by the yeast-malt broth method. The synergistic effect of the combination of amphotericin B (AMPH) and miconazole was observed in nine strains (60%). However, the combinations of AMPH and fluconazole, AMPH and ketoconazole, and AMPH and itraconazole administered simultaneously showed antagonistic effects against three (20%), five (34%), and four (26%) strains, respectively. The effects of combinations of azole antifungal agents administered simultaneously were indifferent or antagonistic against A. fumigatus. In experiments measuring the effects of sequentially administered antifungal agents, however, pretreatment with AMPH and then azole antifungal agents exhibited better in vitro efficacy than that found in experiments measuring the effects of simultaneously administered AMPH and azole compounds.

Antifungal Agents↗

Comparative in vitro exoenzyme-suppressing activities of azithromycin and other macrolide antibiotics against Pseudomonas aeruginosa.

The inhibitory effects of azithromycin (AZM), a new 15-membered macrolide antibiotic, on the production of exotoxin A, total protease, elastase, and phospholipase C by Pseudomonas aeruginosa were determined, and the virulence-suppressing effects of AZM were compared with those of erythromycin (EM), roxithromycin (RXM), and rokitamycin (RKM). The effect of exposure of P. aeruginosa PA103 or B16 in cultures to sub-MICs of these macrolide antibiotics on the production of exoenzymes was determined. AZM suppressed the in vitro production of extracellular and intracellular exotoxin A by P. aeruginosa PA103 more than did EM, even at a concentration of only 2 micrograms/ml. At concentrations of between 4 and 32 micrograms/ml, AZM also inhibited total protease, elastase, and phospholipase C production by P. aeruginosa B16 more than did EM, RXM, and RKM. AZM was effective in suppressing exotoxin A and total protease production through 24 h of incubation in the presence of drug at sub-MICs, but it had no significant effect on either the growth of P. aeruginosa or its total protein production. Moreover, at a concentration of 4 micrograms/ml, AZM suppressed exoenzyme production by other strains of P. aeruginosa more than did EM. These findings indicate that AZM, EM, RXM, and RKM each has an inhibitory effect on exoenzyme production separate from the antimicrobial effect and that, of these macrolides, AZM has the strongest virulence-suppressing effect.

ADP Ribose Transferases↗

Pneumonia caused by Stenotrophomonas maltophilia with a mucoid phenotype.

We describe the first known case of pneumonia caused by a mucoid Stenotrophomonas maltophilia (Xanthomonas maltophilia) strain in a patient with bronchiectasis. The patient was admitted because of mild hemoptysis and productive cough with infiltrative shadow in the right lower lung field on chest X ray. The clinical symptoms were mild, and treatment with minocycline was effective.

Female↗

Detection of Bacteroides fragilis in clinical specimens by PCR.

The direct detection of Bacteroides fragilis from clinical specimens was examined by using the PCR method for amplifying a specific fragment of the glutamine synthetase gene from B. fragilis. By this method, all five B. fragilis strains tested were detected, but DNAs from anaerobic bacteria of 24 other species tested, from aerobic bacteria of 12 species tested, and from human leukocytes were not amplified. Using the nested PCR method, we were able to detect as little as one bacterial cell or 100 fg of chromosomal DNA of B. fragilis. A total of 39 clinical specimens, which consisted of 19 bronchial aspirates, 10 percutaneous lung aspirates, 2 transtracheal aspirates, 6 pleural fluid specimens, and 2 pus specimens, were tested. All four culture-positive samples, of which two were bronchial aspirates, one was pleural fluid, and one was pus, were positive by PCR. Among 35 culture-negative samples, 2 bronchial aspirates were positive by PCR. One was from a patient whose two previous samples were positive by both culture and PCR. It had been submitted for culture several hours after collection, and clindamycin had been administered to the patient before collection of the specimen. The other bronchial aspirate positive by PCR was from a pneumonia patient who had also been administered clindamycin. We believe that B. fragilis was present in these two specimens but that either it was dead, it was below the level detectable by culture, or the process of anaerobic culture was unsuccessful. Thus, the PCR method may be considered useful for the sensitive and rapid detection of anaerobes in clinical specimens.

Bacteroides Infections↗

Double-stranded RNA virus in the human pathogenic fungus Blastomyces dermatitidis.

Double-stranded RNA viruses were detected in a strain of Blastomyces dermatitidis isolated from a patient in Uganda. The viral particles are spherical (mostly 44 to 50 nm in diameter) and consist of about 25% double-stranded RNA (5 kb) and 75% protein (90 kDa). The virus contains transcriptional RNA polymerase activity; it synthesized single-stranded RNA in vitro in a conservative manner. The newly synthesized single-stranded RNA was a full-length strand, and the rate of chain elongation was approximately 170 nucleotides per min. The virus-containing strain shows no morphological difference from virus-free strains in the mycelial phase. Although the association with the presence of the virus is unclear, the virus-infected strain converts to the yeast form at 37 degrees C, but the yeast cells fail to multiply at that temperature.

Blastomyces↗

Possible participation of histamine H3-receptors in the regulation of anaphylactic histamine release from isolated rat peritoneal mast cells.

Anaphylactic histamine release from isolated rat peritoneal mast cells was concentration-dependently blocked by a 5-min treatment with exogenous histamine at 0.9 and 9 microM and enhanced by a 20- to 30-min treatment with thioperamide (H3-antagonist) at 3 microM with significance, but little affected by mepyramine (H1-antagonist) and cimetidine (H2-antagonist) at the cell concentration of 10(6) mast cells/ml. At a low concentration of mast cells (10(4) mast cells/ml), (R)-alpha-methylhistamine (alpha-MH), an H3-agonist, at 0.9-90 microM also inhibited the release in a concentration-dependent fashion. Thioperamide, but neither mepyramine nor cimetidine, significantly restored the decreased release by alpha-MH. However, the complete restoration by thioperamide could not be achieved because the drug itself slightly but concentration-dependently inhibited anaphylactic histamine release. On the other hand, not only betahistine and dimaprit but also alpha-MH did not suppress histamine release from the mast cells induced by compound 48/80. In rat plasma, considerable levels of histamine were detected. From these results, it is strongly suggested that histamine H3-like receptors are largely responsible for the negative feedback regulation of the anaphylactic histamine release from rat peritoneal mast cells.

Anaphylaxis↗

Two-phase increment of Ca2+ uptake, intracellular Ca2+ concentration, and histamine release following antigen stimulation in mouse bone marrow-derived mast cells (BMMC).

The relationship between the influx of Ca2+ into cells or cytosolic Ca2+ concentration ([Ca2+]i) and the histamine release following antigen stimulation in mouse bone marrow-derived mast cells (BMMC) was examined, and the results were compared with those from human lung mast cells (HLMC) and rat peritoneal mast cells (RPMC) in some experiments. Anaphylactic histamine release from BMMC as well as HLMC, but not that from RPMC, was dependent on the extracellular Ca2+. When BMMC were challenged by antigen following radioactive 45Ca2+ addition, two phases of 45Ca2+ influx into the cells were observed. The first phase, which was initiated and completed within 30 sec and 2 min, respectively, after antigen treatment, appeared to be related to anaphylactic histamine release. The second influx began 30 sec subsequent to the first one and lasted for at least 2 min, and this occurred after the completion of the histamine release; So far, it is not known how this second influx participates in the intracellular event(s). On the other hand, only one sustained elevation of [Ca2+]i occurred that reached its maximum within 2 min after antigen stimulation. Following stimulation of BMMC with antigen in the absence of Ca2+, Ca2+ addition 1 to 5 min later time-dependently enhanced the histamine release, although the release was deteriorated by further extension of Ca2+ addition. In contrast, the releasability of HLMC was rapidly decreased. These results indicate that extracellular Ca2+ not only is prerequisite for anaphylactic histamine release from BMMC, but also may modulate the release and participate in some intracellular event(s) which has yet to be focused upon.

Anaphylaxis↗

Two-color analysis of lymphocyte subsets of bronchoalveolar lavage fluid and peripheral blood in Japanese patients with sarcoidosis.

Analysis of T-cell surface markers was carried out in peripheral blood and bronchoalveolar lavage (BAL) fluid of Japanese patients with sarcoidosis to examine the influence of differing racial background. The subjects were 26 untreated patients in whom a diagnosis of active sarcoidosis had recently been established and 9 healthy volunteers, and two-color immunofluorescence analysis was performed. CD3+HLA-DR+ cells, CD4+HLA-DR+ cells, and CD4+CD29+ cells in peripheral blood and BAL fluid were significantly increased in the patients compared with the healthy volunteers, and the mean percentages increased in parallel with the extent of the radiologic stage. The percentage of CD3+HLF-DR+ cells in peripheral blood and lavage fluid also significantly correlated with serum activity of angiotensin-converting enzyme (r = 0.69, p < 0.001; r = 0.61, p < 0.001, respectively). Thus, the evaluation of these antigens' expression is an important clinical approach for the staging of the disease. However, no significant differences were found in CD3+CD25+, CD4+CD45RA+, or CD8+CD11+ cells in either peripheral blood or BAL fluid between the patients and volunteers. Our results indicated that in Japanese patients with sarcoidosis, circulating T cells are activated but CD25+ cells are not increased in peripheral blood and BAL fluid, but there is not a significant association with racial background.

Adult↗