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Biomedical subjects

S Kohno

Publications and source records attributed to S Kohno.

At least 19 recordsLinked to original sources

Mechanism of histamine release by endothelin-1 distinct from that by antigen in mouse bone marrow-derived mast cells.

The mechanisms of endothelin-1-induced histamine release were examined and compared with those responsible for antigen-induced release by using passively sensitized mouse bone marrow-derived mast cells and various drugs that may influence histamine release. The following results were obtained: (1) Although islet-activating protein potently inhibited endothelin-1-induced histamine release, it did not affect the antigen-induced release. (2) Histamine release induced by endothelin-1 was relatively more sensitive to ethylenediaminetetraacetic acid than that induced by antigen, although extracellular Ca2+ is a requisite for both types of the release. (3) (8R*, 9S*, 11S*)-(-)-9- hydroxy-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8,11-epoxy-1H,8H, 11H-2, 7b,11a-triazadibenzo[a,g]cycloocta[c,d,e]trinden-1-one and (8R*, 9S*, 11S*)-(-)-9-hydroxy-9-methoxycarbonyl-8-methyl-14-n-propoxy-2,3,9,10-tet rahydro - 8,11-epoxy-1H,8H,11H-2,7b,11a-triazadibenzo[a,g]cycloocta-[c ,d,e] trinden-1-one, which possibly inhibit protein kinases, strongly inhibited antigen-induced histamine release, while these drugs alone did not inhibit endothelin-1-induced release. (4) Staurosporine, a non-selective protein kinase inhibitor, prevented the elevation of cytosolic Ca2+ concentrations induced by antigen, whereas that induced by endothelin-1 was not influenced; histamine release induced by either stimulus was greatly inhibited by the drug. These results indicate and/or suggest that some biological events induced by endothelin-1 leading to histamine release are different from those involved in the histamine release induced by antigen.

Alkaloids

Plasma (1-->3)-beta-D-glucan measurement in diagnosis of invasive deep mycosis and fungal febrile episodes.

(1-->3)-beta-D-glucan is a characteristic fungal cell-wall constituent. To assess the clinical usefulness of this glucan in screening for invasive fungal infection or fungal febrile episodes, we measured the plasma concentration at the time of routine blood culture in 202 febrile episodes by means of factor G, a horseshoe-crab coagulation enzyme that is extremely sensitive to this polysaccharide. With a plasma cut-off value of 20 pg/mL, 37 of 41 episodes of definite fungal infections (confirmed at necropsy or by microbiology) had positive results (sensitivity 90%). All of 59 episodes of non-fungal infections, tumour fever, or collagen diseases had concentrations below the cut-off value (specificity 100%). Of 102 episodes of fever of unknown origin, 26 had plasma glucan concentrations of more than 20 pg/mL. With those 102 cases taken as non-fungal infections, the positive predictive value of the test was estimated as 59% (37/63), the negative predictive value as 97% (135/139), and the efficiency as 85% (172/202). The positive predictive value should improve if there were a sensitive gold standard that could discriminate fungal from non-fungal infections. Causative fungi included candida, aspergillus, cryptococcus, and trichosporon. Determination of plasma (1-->3)-beta-D-glucan with factor G is a highly sensitive and specific test for invasive deep mycosis and fungal febrile episodes, and will substantially benefit immunocompromised patients.

Adolescent

Detection of (1-3)-beta-D-glucan in a rat model of aspergillosis.

The G test containing factor G, fractioned from the Limulus lysate, was used to detect (1-3)-beta-D-glucan in a rat model of aspergillosis. Aspergillus fumigatus strain MF-13, 1 x 10(4) conidia, were inoculated transtracheally into rats treated with cortisone acetate (100 mg/kg) and fed a low-protein (8%) diet. Increased serum (1-3)-beta-D-glucan was found on the sixth day after inoculation in concentrations of 370 +/- 178 pg/ml (mean +/- SD) in untreated controls, and 154 +/- 43 pg/ml in rats treated with 0.5 mg/kg of amphotericin B. On day 11 (1-3)-beta-D-glucan concentrations were 2,590 +/- 2,940 pg/ml and 448 +/- 442 pg/ml, respectively. The elevation in levels of (1-3)-beta-D-glucan increased in correlation with the elevation of galactomannan antigen titers; (1-3)-beta-D-glucan is thus measurable during experimental aspergillosis in rats.

Amphotericin B

Chromosome elimination in three Baltic, south Pacific and north-east Pacific hagfish species.

We have confirmed that chromosome elimination occurs in the cells of Myxine glutinosa, collected from the Baltic Sea off Sweden, Eptatretus cirrhatus from the south Pacific Ocean off the east coast of New Zealand, and E. stoutii from the north-east Pacific Ocean off Canada, similar to cells of four Japanese hagfish species. In M. Glutinosa, E. cirrhatus type A, E. cirrhatus type B and E. stoutii, the differences in chromosome number between spermatogonia (44, 72, 80 and 48) and somatic cells (28, 34, 34 and 34) were 16, 38, 46 and 14 respectively. The amount of DNA eliminated from presumptive somatic cells averaged 43.5%, 48.7%, 54.6% and 52.8% respectively. Euchromatic chromosomes and/or parts of chromosomes in addition to heterochromatic chromosomes were clearly eliminated in E. cirrhatus and E. stoutii. Adding our previous observations of four Japanese hagfish species, chromosome elimination occurs in all seven of the hagfish species. These results suggest that this phenomenon, chromosome elimination, generally occurs in the order Myxinida. In addition, B-chromosomes were observed in the germ cells of E. cirrhatus and E. stoutii, similar to the cells of E. okinoseanus, E. burgeri and Paramyxine atami (E. atami). This fact suggests that B-chromosomes might exist generally in the family Eptatretidae.

Animals

Choledochal cysts: special emphasis on the usefulness of intraoperative endoscopy.

Long-term complications after excisional surgery for choledochal cyst include stone formation within the intrahepatic bile duct (IHBD) and within the intrapancreatic portion of the bile duct (IPBD). The authors reviewed 180 patients with choledochal cysts (137 women) seen during a 30-year period and report their recent experience with intraoperative cyst endoscopy. Primary cyst excision with hepaticoenterostomy was performed in 150 cases, and a secondary cyst excision, after various lesser drainage procedures, in 24. Six children were treated early in the series with a cyst enterostomy. The mean age and follow-up period were 4.3 and 9.4 years, respectively. At surgery, dilatation of the IHBD was identified in 96 patients, and protein plugs or stones were observed in 31 common pancreaticobiliary channels. Fifty-five common channels were noted to be dilated. Hepaticojejunostomy was performed in 123 patients without intraoperative endoscopy. Late stone formation occurred within the IHBD in 4 of these cases and within residual segments of intrapancreatic cyst in 2 (mean age and follow-up period were 4.9 and 13.0 years, respectively). Intraoperative endoscopy was performed in 51 patients (mean age and follow-up period 3.6 and 4.3 years), and stone formation has not been observed in any patients in this group. Intraoperative cyst endoscopy is recommended as a valuable adjunct to choledochal cyst excision.

Adolescent

T cell-dependent activation of macrophages and enhancement of their phagocytic activity in the lungs of mice inoculated with heat-killed Cryptococcus neoformans: involvement of IFN-gamma and its protective effect against cryptococcal infection.

Previous investigations have demonstrated that macrophages play a critical role in the first-line cellular defense mechanism against infection with Cryptococcus neoformans. In the present study, to elucidate the way in which anticryptococcal activity of macrophages is regulated at the site of infection, pulmonary intraparenchymal macrophages were directly analyzed for expression of their surface molecules and their phagocytic activities against the organism, and the effects of depletion of T cells and endogenous IFN-gamma in vivo on these parameters were examined. In the lungs of mice intratracheally inoculated with heat-killed C. neoformans, macrophages were activated, as indicated by augmented expression of MHC class II, intercellular adhesion molecule-1 (ICAM-1) and Fc receptor (FcR), and about two-thirds of macrophages were found to have ingested an average of 3.77 +/- 0.12 yeast cells per macrophage. In mice depleted of both CD4+ and CD8+ T cells by injecting the specific monoclonal antibodies (mAbs) or anti-IFN-gamma mAb, not only augmentation of the expression of macrophage activation markers but also phagocytosis of C. neoformans was significantly reduced. These results suggest that anticryptococcal activity of macrophages is regulated by IFN-gamma endogenously produced by T cells. Additionally, treatment with IFN-gamma were shown to significantly prolong the survival time of mice infected with viable C. neoformans. Additionally, preimmunization with heat-killed C. neoformans significantly prolonged the survival time of mice which received the following infection.

Animals

Mean power frequency shift during fatigue and recovery in patients with craniomandibular disorders.

EMG spectral shifts of anterior temporal and medial masseter muscles were evaluated. Mean power frequency (MPF) shift during fatigue and recovery of 46 healthy subjects and 46 patients with craniomandibular disorder were recorded at the beginning and the end of fatiguing clenching, then 3, 8, 13 and 18 min following the fatiguing clenching. The reference clenching force was 80% of each subject's maximal voluntary contraction (MVC). Recording was stopped when subjects felt pain or discomfort. Significance was found between the healthy group (N) and the diseases group (CMD) in the three following points: (i) the mean of MPF values of the masseter muscles at the end of fatiguing clenching; (ii) the recovery pattern of the temporal muscles; and (iii) MPF shift induced by fatiguing clenching. Our results therefore suggest that MPF reflects several aspects of craniomandibular disorders. Thus, measuring fatigue and recovery MPF could be useful in the screening of CMD.

Adult

[Yearly changes of isolated organisms from the respiratory tract in Hokusho Central Hospital].

Isolated organisms from the respiratory tract have been studied in our hospital from 1986 to 1993. The total number of samples were 18,345 and samples which showed 10(5) cfu/ml organisms were 8648 in our hospital for 8 years. Enterobacteriacae, Pseudomonas aeruginosa, Haemophilus influenzae, Streptococcus pneumoniae, and glucose nonfermenting gram-negative rods were major isolates in 8 years. Haemophilus influenzae, which used to be the commonest isolate, decreased from 10.9% in 1993 while Enterobacteriacae increased from 8.9% in 1986 to 17.6% in 1993. S. pneumoniae and H. influenzae were major isolates from out-patients consisting of 50%, followed by Enterobacteriacae, P. aeruginosa and MSSA. Enterobacteriacae and P. aeruginosa were major isolates from in-patients, followed by MRSA and beta-Streptococcus. Streptococcus agalactiae, Serratia marcescens and Corynebacterium spp. prevailed especially in the geriatric ward. S. pneumoniae, H. influenzae and M. catarrhalis were major isolates from patients with pneumoconiosis, especially in winter.

Bacteria

[Basic and clinical evaluation of lysis centrifugation in candidemia].

Basic and clinical evaluation of lysis centrifugation using Isolator 10 was performed and compared with culture bottle methods. Blood, which was inoculated with C. albicans, C. tropicalis or C. parapsilosis, was cultured using lysis centrifugation or culture bottle method. The culture duration of C. albicans and C. parapsilosis by lysis centrifugation was shorter than that by the culture bottle (BHI release). C. albicans, C. parapsilosis and C. tropicalis became culture-positive within 1 or 2 days after culture by lysis centrifugation. C. albicans and C. parapsilosis became positive 4 days and C. tropicalis 6-8 days after culture by the culture bottle (BHI super). Clinical evaluation of both blood culture method as performed from April 1990 to March 1994. Sixty samples (4.4%) were positive out of 1370 samples. Twenty eight samples (7.2%) were positive out of 389 samples, which were examined by both methods. Twenty two samples were positive by both methods and the rest of the 6 samples was positive only by Lysis centrifugation.

Blood

[A report to 2 cases where Stenotrophomonas maltophilia with a mucoid phenotype was isolated from the sputum].

Mucoid Stenotrophomonas maltophilia was isolated from the sputum of 2 women. Case 1 which we reported recently was primary pneumonia caused by S. maltophilia. However, in Case 2, mucoid S. maltophilia represented part of the transient flora. Interestingly, colonization of mucoid Pseudomonas aeruginosa on respiratory tract occurred in both cases after mucoid S. maltophilia was isolated from their sputum.

Female

Disseminated intravascular coagulopathy in infection compared with that in malignant neoplasia.

The organic symptoms and results of coagulation tests of disseminated intravascular coagulopathy (DIC) in 17 patients with infection were compared with those in 12 patients with malignancy. The infectious diseases were mainly sepsis and pneumonia, and the malignancy was mainly lung cancer. The mean antithrombin III (AT III) before treatment was 54% in infection and 68% in malignancy, and the AT III values improved after administration of 1500 U of AT III concentrates per day. The mean thrombin-antithrombin complex level decreased from 22 ng/ml to 9 ng/ml after the treatment in infection, but it increased in malignancy. There were no differences in DIC scores between infection and malignancy before treatment; however, the scores were significantly more improved in infection than in malignancy after treatment (p < 0.05). The fibrin/fibrinogen degradation product level, platelet count, and fibronectin level were also significantly more improved in infection than in malignancy. This better response to treatment in infection than in malignancy is probably due to eradication of the causative organisms by antibiotics in infection. These data suggest that therapy against both DIC and the underlying disease is crucial for successful treatment.

Aged

[Isolation of Cryptococcus neoformans from environments (pigeon excreta) in Nagasaki].

Cryptococcosis is one of the serious deep-seated mycoses in immunocompromised patients, especially those with AIDS. Cryptococcus neoformans ordinarily lives in natural environments such as soil and reproduces in pigeon excreta. It spreads in the air and infects human by inhalation. We isolated C. neoformans from pigeon excreta in hospitals, private houses, parks in Nagasaki from October to December in 1994. C. neoformans was isolated from 4 of 8 samples (50%) of pigeon excreta and the isolation rate increased to 80% (4/5) if they were weathered excreta. Two patients with pulmonary cryptococcosis occurred in the last two years in the area where C. neoformans was isolated during that period. Epidemiological studies of clinical isolates and environmental isolates are important to determine its origin of infection and the route of transmission.

Animals

[A study of defensins in bronchoalveolar lavage fluid in patients with diffuse panbronchiolitis].

We estimated defensins, antimicrobial and cytotoxic peptides localized in azurophil granules of neutrophils, in bronchoalveolar lavage fluid (BALF) in patients with diffuse panbronchiolitis (DPB). BALF from DPB patients contained a higher concentration of defensins than those from patients with idiopathic pulmonary fibrosis and healthy volunteers. A significant correlation was observed between the concentration of defensins and the number of neutrophils, the concentration of interleukin-8 or neutrophil elastase in BALF of DPB patients. An immunohistochemical defensins in neutrophils and mucinous exudates in the airways and in the surface of bronchiolar epithelial cells. After treatment with macrolide antibiotics, significant reductions in the concentrations of defensins, IL-8 and neutrophil numbers in BALF of DPB patients were observed. These findings suggest that the lung injury in DPB could be caused by defensins released by neutrophils accumulated in the airways.

Adult

Trends in antimicrobial resistance of Streptococcus pneumoniae in Japan.

A total of 184 isolates of Streptococcus pneumoniae were recovered from the sputa of patients over a 5-year period in the Nagasaki area and were examined. A total of 30 strains were resistant to penicillin (MIC, > or = 0.10 micrograms/ml), 13 of which belonged to serotype 19B. These strains showed decreased susceptibility to other antimicrobial agents. Vancomycin, cefpirome, and imipenem were the most active agents tested.

Anti-Bacterial Agents

Increase in activated CD8+ cells in bronchoalveolar lavage fluid in patients with diffuse panbronchiolitis.

To study the role of T cells in diffuse panbronchiolitis (DPB), we investigated T-cell subsets in bronchoalveolar lavage fluid (BALF) or 33 patients with DPB, nine patients with bronchiectasis, and 20 healthy volunteers. BALF from DPB patients contained a higher percentage of neutrophils than that from patients with bronchiectasis or healthy volunteers, whereas the percentage of lymphocytes was similar in the three groups. DPB patients, however, had a higher number of lymphocytes and a reduced CD4/CD8 ratio compared with the other subjects. A two-color analysis of T-cell subsets in peripheral blood and BALF revealed a significant increase in the percentage and number of CD8+HLA-DR+ cells and in the number of CD4+HLA-DR+ cells in BALF of DPB patients. The expression of the adhesion molecules CD 11a and CD18 on lung CD3+ cells was enhanced over that on blood CD3+ cells in DPB patients. However, there was no significant difference in the expression of these antigens in peripheral blood or BALF among the groups. There was no significant relationship between BALF interleukin (IL)-8 and lymphocyte accumulation in the lungs of the DPB patients, whereas a significant correlation between the percentage of neutrophils and IL-8 levels in BALF of DPB patients was observed. After treatment with macrolide antibiotics, a significant reduction in the number of lymphocytes and activated CD8+ cells and an elevation in the CD4/CD8 ratio in BALF of DPB patients was observed. Our findings suggest an activation of CD8+ cells in the airway lumen of DPB patients, supporting the hypothesis that lymphocytes are important cellular components of bronchial inflammation in DPB.

Anti-Bacterial Agents

Leukotriene B4 in bronchoalveolar lavage fluid of patients with diffuse panbronchiolitis.

Leukotriene B4 (LTB4) is a potent proinflammatory mediator that may be of particular relevance to the pathology of several respiratory diseases. We have previously reported that neutrophil chemotactic mediators in the lavage fluid of patients with diffuse panbronchiolitis (DPB) consist of many components. In this study, we evaluated the effect of erythromycin (EM) on the pathogenesis of DPB, by examining the level of LTB4 in the bronchoalveolar lavage (BAL) fluid, and determining the relationship between the level and neutrophil accumulation into the respiratory tract. Pre-EM treatment neutrophil chemotactic activity (NCA) in the patients with DPB was significantly increased compared with that in five healthy nonsmoking volunteers (HVs) (p < 0.001), and the level was markedly reduced after EM treatment (p < 0.001). The amounts of LTB4, detected in the BAL fluid from the patients, was also significantly higher than those in control subjects (3.5 +/- 1.1 ng/mL vs 0.1 +/- 0.0 ng/mL, p < 0.001), and the level was significantly reduced after EM treatment (0.6 +/- 0.3 ng/mL, p < 0.01). In addition, the percent reduction of the level of LTB4 was significantly correlated with NCA (r = 0.832, p < 0.01); the reduction was also significantly correlated with neutrophil percentage before and after EM treatment (r = 0.778, p < 0.05). These findings provide evidence for the potent role of LTB4 in the respiratory tracts of patients with DPB and suggest that this lipoxygenase metabolite is involved in the recruitment of neutrophils into the airways of the patients. Our findings suggest that LTB4 is one of the most important chemotactic mediators that has a pathogenetic role in the airway damage of DPB. Erythromycin might inhibit the production of this mediator, restrict the neutrophil accumulation, modulate the excessive inflammation in the respiratory tract, and ultimately improve the pathogenesis of DPB.

Adult

Increase of activated T-cells in BAL fluid of Japanese patients with bronchiolitis obliterans organizing pneumonia and chronic eosinophilic pneumonia.

To study the role of T cells in bronchiolitis obliterans organizing pneumonia (BOOP) and chronic eosinophilic pneumonia (CEP) and to examine the influence of differing racial background, T-cell subsets in bronchoalveolar lavage (BAL) fluid (BALF) and in peripheral blood of 8 Japanese patients with idiopathic BOOP and 5 with CEP were compared with those of 15 normal subjects. The BALF pattern in BOOP was characterized by a significantly high number and percentage of lymphocyte and by a low CD4 to CD8 ratio compared with patients with CEP and healthy volunteers. Patients with CEP showed a significantly higher percentage of BALF eosinophils compared with other groups. There was no significant difference in BALF CD4 to CD8 ratio between patients with CEP and volunteers. Two-color analysis of T-cell subsets revealed that CD3+HLA-DR+ cells (activated T cell) in BALF of patients with BOOP and CEP increased significantly compared with volunteers, while BALF CD3+CD25+ cells (interleukin 2 receptor+ T-cell) did not. In addition, BALF CD8+HLA-DR+ cells (activated suppressor/cytotoxic T cell) in patients with BOOP and CD4+HLA-DR+ cells (activated helper T cell) in patients with CEP were significantly higher than levels detected in healthy subjects. The percentage of CD8+CD57+ cells and the number of CD8+CD11b- cells (cytotoxic T cell) in BALF were significantly higher in patients with BOOP compared with patients with CEP and healthy volunteers. There were no significant differences in the expression of peripheral blood T-lymphocyte surface antigens among the groups. These findings indicate that cytotoxic T cells in Japanese patients with idiopathic BOOP and helper T cells in CEP appear in the lungs is consistent with a previous report in Caucasians, supporting the hypothesis that T cells may play an important role in the pathogenesis of these diseases.

Aged

Usual interstitial pneumonia associated with primary Sjögren's syndrome.

We describe the first case, to our knowledge, of usual interstitial pneumonia (UIP) as the pulmonary manifestation in primary Sjögren's syndrome (SjS). A 45-year-old woman was admitted to our hospital because of a dry cough and an interstitial shadow on a chest roentgenogram. Labial biopsy and sialogram confirmed a diagnosis of SjS. BAL fluid analysis revealed lymphocytosis with a decreased CD4/CD8 ratio compatible with bronchiolitis obliterans organizing pneumonia or lymphoid interstitial pneumonia. Open-lung biopsy specimen, however, showed evidence of UIP. Open-lung biopsy was a useful and necessary examination to determine the nature of the pulmonary complication in primary SjS. Conservative treatment without corticosteroids maintained a stable condition for a follow-up period of 3 years.

Female