PubMed Health⌕ Search

Biomedical subjects

S Ohga

Publications and source records attributed to S Ohga.

At least 91 records · Page 5Linked to original sources
PubMed1992

The inflammatory cytokines in measles: correlation between serum interferon-gamma levels and lymphocyte subpopulations.

Interleukin-1 (IL-1 beta), tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) were measured in serum from children with measles using an immunoradiometric assay. The IFN-gamma level was increased in 52 out of 54 patients in the acute phase of measles (less than 7 days of illness), and then declined to an undetectable level in the convalescent phase. Neither IL-1 nor TNF could be detected during the course of the illness. The mean serum IFN-gamma level was at its peak on day 4 and could be detected over a 7-day period after the onset of fever, coinciding with the febrile period (6.9 +/- 1.5 days). In the acute phase, the phytohaemagglutinin responses, absolute number of platelets, total lymphocyte counts, CD3+, CD4+, CD8+ cell counts and the CD4/8 ratio were depressed, while stab cell number and lactate dehydrogenase levels were higher than those in the convalescent phase. Using Spearman rank sum test, the IFN-gamma level was correlated negatively with the peripheral lymphocyte (P less than 0.01), CD3+ (P less than 0.05), CD4+ (P less than 0.05) cell counts and the CD4/8 ratio (P less than 0.05) and correlated positively with the stab cell count (P less than 0.01) but not with any other parameter. When the acute phase findings were compared between 28 complicated and 40 uncomplicated patients, the former were younger (P less than 0.01) and had higher maximum body temperature during the illness (P less than 0.05) than the latter, there was no difference in their IFN-gamma levels. These results show that endogenous IFN-gamma appears in the circulation during the acute febrile phase of measles, but does not contribute directly to any complication of the disease.

Acute Disease↗
PubMed1992

The measles outbreak in Chikuhou District, Fukuoka, Japan, 1990: correlation between herd immunity level and outbreak size.

A measles outbreak occurred in the Chikuhou district of Fukuoka, Japan from May to October 1990, during which 71 patients were cared for at the Itoda Public Hospital. Hospital records revealed a large outbreak in the adjacent town of Kanada. In order to characterize the outbreak, questionnaires were sent to all preschool-age children in Itoda (73% effective response) and in Kanada (76% effective response) requesting information about their vaccination and/or history of measles. The number of patients was 22 (4%) in Itoda and 63 (14%) in Kanada, most of these being preschoolers, while the vaccination rate was 61% and 44%, respectively. The herd immunity levels in age-specific groups were compared between the two towns. Before the epidemic, the immunity level of 1 year old children in Kanada, who showed the higher attack rate, was lower (18%) than that in Itoda (39%), while after the epidemic it rose above 60% in both towns. When we studied the correlation between the attack rate and the vaccination rate, or the number of children susceptible to measles (susceptibility rate) in each preschool, the attack rate correlated negatively with the vaccination rate (correlation coefficient [CC] = -0.818; P less than 0.01), and positively with the susceptibility rate (CC 0.860; P less than 0.01). The regressed equation on the correlation indicated that the immunity level should be more than 70% to keep the attack rate under 5% in preschools. After the epidemic, the immunity levels of all preschoolers reached above 70%.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1992

Outbreaks of group A beta-hemolytic streptococcal pharyngitis in children: correlation of serotype T4 with scarlet fever.

We evaluated the clinical features of 121 children who had group A beta-hemolytic streptococcal (GABHS) pharyngitis during 2 outbreaks in the Chikuhou district, Fukuoka, Japan, with respect to T types. During the first outbreak (November 1989-February 1990), T12 (50%) and T22 (27%) were the dominant T types isolated. During the second outbreak (January-April 1991), 64% of the typable strains were T4. Pus on the tonsils was less common and strawberry tongue more common in patients with eruptions than in those without. Skin eruptions were much more common in the patients infected with T4 than with other T types (p < 0.001). Despite a 10-day regimen of amoxicillin, 12/69 patients (17.4%) had evidence of GABHS on repeat cultures. The results suggest that T4 may be associated with a high incidence of scarlet fever. Serotyping should be performed to identify disease carriers and patterns of GABHS infection.

Adolescent↗
PubMed1992

Ultrastructural analysis of platelet-like particles from a human megakaryocytic leukemia cell line (CMK 11-5).

Ultrastructural observations were performed to further characterize the human megakaryocytic leukemia cell line, CMK, and its subclone, CMK11-5. We found that particles derived from CMK11-5 cells had cytoplasmic projections and no nucleus, and that some particles contained alpha granules. Incubation with ADP induced fibrinogen receptors on the surface of these particles. Furthermore, the particles had glycoprotein Ib antigen on their surfaces, and attached nonreversibly to rabbit aortic subendothelium, showing associated morphological changes similar to those observed in normal platelets. CMK and CMK11-5 are the first megakaryocytic cell lines that have been found to release particles that have some of the same functions as normal platelets. In particular, CMK11-5 seems to be a useful model for studying megakaryocyte function.

Blood Platelets↗
PubMed1991

Microparticle generation during in vitro platelet activation by anti-CD9 murine monoclonal antibodies.

We used flow cytometry and two anti-CD9 murine monoclonal antibodies (NNKY1-19, MALL13) to investigate the glycoprotein composition and the potential functions of microparticles (MP) released by platelets exposed to these antibodies in vitro. NNKY1-19 produced aggregation with characteristics similar to those noted in previous reports. The action of MALL13 on platelets in platelet-rich plasma (PRP), however, differs from that of other anti-CD9 antibodies. The normal fluctuation in the MALL13-induced change in optical density disappeared when complement was present. MALL13-induced effect for platelet in PRP was not inhibited by preincubation with monoclonal anti-GPIIb/IIIa antibody, but was inhibited in washed platelets (WP). Furthermore, following MALL13 stimulation in PRP platelets, the amount of buffer LDH markedly increased and electron microscopy findings showed vacuoles appearing inside the platelets. These results suggest that MALL13 has at least two effects on platelets that differ for PRP platelets and WP. The number of MP released was increased by the addition of anti-CD9 antibodies. MP surfaces were found to be rich in CD9 protein. MALL13 stimulation lead to a significant increase in the binding of C1q and C3 to platelets and caused the production of MP to occur more rapidly than it did the exposure of fibrinogen binding sites in the presence of complement. The analysis of the relationship of MP to anti-CD9 monoclonal antibody may be useful in the investigation of the relationship between platelet function and coagulation regulation.

Antibodies, Monoclonal↗
PubMed1991

Aseptic meningitis in children: correlation between fever and interferon-gamma level.

We studied the correlation between interleukin-1 beta (IL-1 beta), tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) in cerebrospinal fluid (CSF) and clinical/laboratory findings in children with aseptic meningitis. In 19/27 patients (70%), the CSF IFN level was high at initial diagnosis, and reduced to a low or undetectable level during the convalescent phase (5-14 days later) of the disease. There were no differences in IL-1 beta and TNF-alpha levels between the acute and convalescent phase of the patients. The serum IFN-gamma levels in the patients, which were simultaneously examined were undetectable in the acute phase. When we compared the clinical/laboratory findings between the 29 patients with detectable CSF IFN-gamma level and the 21 patients with an undetectable CSF IFN-gamma level in the acute phase, the former demonstrated higher body temperature (P less than 0.01), and higher cell number and protein level in the CSF (P less than 0.05) than the latter. On the other hand, there were no significant differences in the duration of meningeal signs, the titre of C-reactive protein, and the peripheral leucocyte count between the two groups. By the Spearman's rank sum test, the CSF IFN-gamma levels correlated more definitively with the severity of febrile episode (maximal body temperature, duration of fever and body temperature at the first lumbar tap), and the cell number and protein level in the CSF. These results suggest that IFN-gamma produced in the inflamed intrathecal space may be associated with the pathogenesis of aseptic meningitis, especially the production of fever.

Child↗
PubMed1991

Tumor necrosis factor in the cerebrospinal fluid of children with central nervous system leukemia.

To clarify the role of cytokines in cerebrospinal fluid (CSF) in the pathogenesis of central nervous system (CNS) leukemia, three cytokine activities, interleukin 1 (IL-1)-beta, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma, and their correlations with other laboratory studies of the CSF were analysed in 23 children with acute leukemia. These patients were classified into three groups: group A (n = 8)--patients with overt CNS leukemia, group B (n = 5)--patients with CNS leukemia in remission, group C (n = 10)--patients without CNS disease. IFN-gamma in the CSF was undetectable in these 23 patients. There was no difference in IL-1-beta levels among the three groups. However, TNF-alpha levels were significantly higher in group A than in group B, and higher in group B than in group C. By Kendall's rank sum test, high TNF levels in CSF correlated with high CSF leukemic cell counts and low sugar levels. In two patients with overt CNS leukemia, the TNF level in the CSF decreased gradually with intrathecal chemotherapy. These results indicate that TNF released from stimulated cells in the cerebrospinal space may induce CNS leukemia-related symptoms or alter laboratory parameters measured in the CSF. TNF levels in CSF may also prove useful in diagnosing early CNS involvement in children with acute leukemia.

Acute Disease↗
PubMed1991

Prognosis of children with virus-associated hemophagocytic syndrome and malignant histiocytosis: correlation with levels of serum interleukin-1 and tumor necrosis factor.

To clarify the correlation of cytokine level with the severity and prognosis of children with the hemophagocytic syndrome, we analyzed serum interleukin-1 (IL-1) and tumor necrosis factor (TNF) levels in 26 children with either the virus-associated hemophagocytic syndrome (VAHS, n = 12) or malignant histiocytosis (MH, n = 14). When compared to healthy controls, 13 children had an elevated IL-1 (greater than or equal to 20 pg/ml) and 21 children had an elevated TNF (greater than or equal to 10 pg/ml) level at diagnosis. There was however, no significant difference in the frequency of these high levels between the patients with VAHS and MH. Neither IL-1 nor TNF levels correlated with other clinical or laboratory findings in either VAHS or MH. Two of the 12 patients with VAHS died of an intracranial hemorrhage and 7 of the 14 patients with MH died despite chemotherapy. The MH patients who had a high TNF level (greater than or equal to 50 pg/ml) had a poorer prognosis than those with a low TNF level (less than 50 pg/ml; p less than 0.01). In MH patients, other parameters, such as coagulopathy and lactic dehydrogenase, ferritin and IL-1 levels, did not correlate with prognosis. In 3 patients (2 with VAHS and 1 with MH) analyzed periodically, the change in TNF level was closely associated with the clinical progression or regression of the diseases. Serum cytokine levels may thus be monitored not only for predicting the severity and prognosis of VAHS or MH but also for determining the indications for or timing of chemotherapy. Moreover, TNF may play an important role in the progression of VAHS and MH.

Adolescent↗
PubMed1991

[Primary myelofibrosis transforming into multiple subcutaneous monoblastoma--a case report].

A 83-year-old man was diagnosed with primary myelofibrosis based on the presence of leukoerythroblastosis, splenomegaly, chromosome 46 XY, a dry tap bone marrow aspiration and fibrosis on bone marrow biopsy, when he was admitted for herpes zoster in June 1987. He was admitted for a second time with multiple subcutaneous tumors over his entire body in July, 1989. He had mild splenomegaly, but no hepatomegaly nor lymphadenopathy. Laboratory tests were as follows: RBC 214 x 10(4)/microliters, Hb 5.1 g/dl, Ht 17.7%, WBC 3,200/microliters with leukoerythroblastosis, platelets 11.6 x 10(4)/microliters, s-lysozyme 251 micrograms/ml, u-lysozyme 770 micrograms/ml, NAP ratio 98%, score 278. Bone marrow aspiration resulted in a dry tap. Bone marrow biopsy showed marked fibrosis. Histologic examination of subcutaneous tumor biopsy specimens revealed a diffuse infiltration of monocytes with flexuous nuclei. These cells were positive for alpha-naphtyl butyrate esterase stain, and negative for peroxidase, alpha-naphtol ASD chloroacetate esterase stain and platelet glycoprotein IIb/IIIa stain (APAAP). Ultrastructurally, these cells were mostly monocytes and promonocytes, while phenotypically, CD11b, CD13, CD14, CD33 and HLA-DR were positive. These date indicated that the subcutaneous tumors originated from monocytes.

Aged↗
PubMed1991

The ultrastructure and distribution of fibrinogen, von Willebrand factor, and glycoprotein IIb/IIIa complex in platelet alpha-granules by cryo-ultramicrotomy.

Transformation upon mild stimulation and the ultrastructure of blood platelet alpha-granules were examined using cryo-ultramicrotomy. An ultrastructural study found not only round, but also elongated and drumstick-shaped alpha-granules and rod-like structures protruding from round alpha-granules. Some elongated alpha-granules showed distinctive cross-striations in the short axis with a periodicity in the order of 19-22 nm. Gold particle-labeled fibrinogen (Fbg) was observed on elongated alpha-granules having cross-striations. Electron-dense nucleoids were observed on some round alpha-granules. An electron-dense nucleoid, intermediate zone, and an electron-lucent matrix were noted in round alpha-granules by gold particle-labeled Fbg in the intermediate zone. Gold particle-labeled von Willebrand factor (vWF) was observed in alpha-granules except in nucleoid zones. Labeling for Fbg was also observed in rod-like structures protruding from round alpha-granules. Gold particle-labeled glycoprotein (GP)IIb/IIIa complex was observed on the inner face of alpha-granule membranes. A few elongated and drumstick-like alpha-granules were found on freshly fixed platelets. Elongated alpha-granules were only found in a small percentage of washed and collagen-stimulated platelets. Cryo-ultramicrotomy is useful for examination of the distribution of intracellular antigens.

Blood Platelets↗
PubMed1991

Deletion of self-reactive T cells in the donor-derived T cells but not in the host-derived T cells in fully allogeneic radiation chimeras. Mls-reactive T cells in allogeneic radiation chimeras.

Kinetics of T cells bearing V beta 6 capable of recognizing Mls-1a were examined in the thymus and peripheral lymphoid organs of two allogeneic bone marrow chimeras; AKR/J(H-2k, Thy1.1,Mls-1a)----C3H/He(H-2k, Thy1.2,Mls-1b) and AKR/J----C57BL/6(H-2b,Thy1.2, Mls-1b). Sequential appearance of host- and donor-derived T cells occurred in the thymus and the peripheral lymphoid organs of both AKR----C3H and AKR----B6 chimeras. The first cells to repopulate the thymus were Thy1.2+ host-derived radioresistant cells, which were synchronized in their development. The host-derived cells in thymus of AKR----B6 chimeras differentiate more rapidly than those in AKR----C3H chimeras. An almost complete replacement from host-derived cells to donor-derived cells occurred by day 21 after reconstitution in AKR----C3H and AKR----B6 chimeras. In the donor-derived thymocytes, none of CD4- or CD8-single positive thymocytes expressed high density of V beta 6 in either AKR----C3H or AKR----B6 chimeras, whereas the host-derived thymocytes in AKR----B6 chimeras contained an appreciable number of CD4-single positive thymocytes bearing V beta 6. In the peripheral lymphoid organs, T cells bearing V beta 6 were virtually abolished in Thy1.1+ cell pool of both AKR----C3H and AKR----B6 chimeras. While V beta 6+ T cells of host-origin were detected in the peripheral lymphoid organs in AKR----B6 chimeras. These result indicated that the donor-derived mature T cells showed deletion of V beta 6 in the thymus and the peripheral lymphoid organs in both AKR----C3H and AKR----B6 chimeras, whereas lack of V beta 6 deletion was observed in the host-derived mature T cells in the AKR----B6 chimeras. These results suggested that the host-derived thymocytes may likely to escape undergoing a negative selection against donor-phenotype in the radiation bone marrow chimeras.

Animals↗
PubMed1991

Serum interleukin-1 and tumor necrosis factor activities in febrile children with acute leukemia.

In order to determine whether a relationship exists between levels of serum interleukin-1 (IL-1) and tumor necrosis factor (TNF) and the incidence of fever in malignant disease and infection, IL-1 and TNF levels in 60 children with acute leukemia, 18 children with bacterial infection, and 10 children with viral infection were compared with those of 20 healthy children. IL-1 levels greater than 100 pg/ml were seen in two febrile leukemic patients and six bacteria-infected patients, and the bacteria-infected group as a whole had IL-1 levels significantly higher than those of healthy children (p less than 0.05). TNF levels greater than 50 pg/ml were noted in six febrile leukemic patients and two bacteria-infected patients (both of whom were complicated by septic shock). No single group showed significantly higher levels when compared to healthy children. All patients showing high IL-1 or TNF levels had fevers at the time of diagnosis. These findings suggest that fever in bacterial infection is associated with the production of IL-1 but not TNF (except in cases of septic shock), whereas fever in acute leukemia may be associated with the production of either IL-1 or TNF. Monitoring patients with acute leukemia for IL-1 and TNF levels throughout the clinical course of disease may help clarify the causes of febrile episodes.

Child↗
PubMed1990

Human gamma delta T-cell receptor-positive cell-mediated inhibition of erythropoiesis in vitro in a patient with type I autoimmune polyglandular syndrome and pure red blood cell aplasia.

The gamma delta T-cell receptor-positive (gamma delta TCR+) lymphocytes were markedly expanded up to 68% of peripheral blood lymphocytes in a case with type I autoimmune polyglandular syndrome and pure red blood cell aplasia (PRCA). The gamma delta TCR+ cells showed CD4 negative, 16% dim-CD8 positive and 10% to 46% human leukocyte antigen-D-related (HLA-DR) positive, and exhibited no monoclonality as assessed by the patterns of TCR gene rearrangements. Functional studies revealed that the proliferative responses of the patient's peripheral blood mononuclear cells (PBMC) were severely depressed to candida antigen, alloantigens, and autoantigens (non-T cells). The gamma delta TCR+ cells had no suppressive effect on the proliferative response of the alpha beta TCR+ cells to candida. The patient's PBMC, isolated gamma delta TCR+ cells but not alpha beta TCR+ cells, exhibited non-major histocompatibility complex (MHC)-restricted cytotoxicity. Furthermore, the patient's PBMC and isolated gamma delta TCR+ cells inhibited burst-forming units-erythroid (BFU-E), but not colony-forming units/granulocyte-macrophage (CFU-GM). Supernatants derived from the patient's T cells similarly inhibited BFU-E but not CFU-GM. The clinical course of the patient also showed a close correlation between the decreased number of total lymphocyte counts, especially HLA-DR + gamma delta TCR+ cell counts, and recovery from PRCA. These observations suggest that the gamma delta TCR+ cells might be functional in vivo and involved in the pathogenesis of PRCA in this patient.

Adult↗
PubMed1990

Sequential appearance of gamma/delta- and alpha/beta-bearing T cells in the peritoneal cavity during an i.p. infection with Listeria monocytogenes.

To search for a potential role of T cell antigen receptor (TcR) gamma/delta-bearing cells in host-defense against Listeria monocytogenes, we analyzed the sequential appearance of gamma/delta and alpha/beta T cell in the peritoneal exudate cells (PEC) during an i.p. infection with sublethal dose (2 X 10(3) of viable Listeria organisms in mice. The PEC on day 1 after the infection consisted of 48% macrophages and 50% lymphocytes, most of which were surface IgM+ (B) cells. The number of PEC increased to the maximal level by day 3. The PEC at this stage contained an appreciable number of CD3+ T cells in addition to a large number of macrophages. Of the CD3+ cells, the proportion of CD4- CD8- cells, most of which expressed no TcR alpha/beta, increased to the maximal level on day 3 after the infection. In correlation with an increased number of CD3+ CD4- CD8- TcR alpha/beta- cells, high level of TcR gamma/delta chain gene messages was detected in the nonadherent population of the PEC on this stage. On the other hand, the PEC on day 8 contained an increased number of CD4+ CD8- and CD4- CD8+ cells which expressed TcR alpha/beta chain on their surface. These results suggest that the gamma/delta T cells precede the alpha/beta T cells in appearance during listerial infection. The gamma/delta T cells may be involved at the first line of the host-defense against Listeria.

Animals↗
PubMed1990

Augmentation of host defense against Listeria monocytogenes infection by oral administration with polysaccharide RBS (RON).

Protection against Listeria monocytogenes in mice was enhanced by oral administration with a 30 mg/kg/day dose of polysaccharide RBS for 10 days. In mice treated with RBS, an enhanced elimination in vivo of L. monocytogenes was observed at the relatively late phase of listerial infection in correlation with enhanced immune responses against L. monocytogenes. The peritoneal macrophages from mice treated with RBS exhibited an increased activity of accessory cells for immune responses as assessed by production of interleukin-1 and antigen presentation to Listeria-immune T-cells. An increased activity of macrophages acting as accessory cells for immune responses may play important roles in the enhanced resistance against L. monocytogenes in mice treated orally with RBS.

Actins↗
PubMed1990

Effects of stimulated or immunologically activated macrophages on the induction of immune responses to Listeria monocytogenes.

The influences of peritoneal macrophages induced by proteose peptone, Corynebacterium parvum (C. parvum) or Bacillus Calmette Guérin (BCG) on the initiation and development of immune responses and protection against Listeria monocytogenes infection were studied in mice. Mice treated intraperitoneally (i.p.) with proteose peptone 4 days previously showed much the same level of protection against an intraperitoneal infection with Listeria as untreated mice. Mice treated i.p. with C. parvum 4 days previously, of which peritoneal macrophages had increased abilities for intracellular killing of Listeria and O2- generation as compared with peptone-elicited macrophages, exhibited an enhanced resistance against the listerial infection. The degree of immune responses, as assessed by delayed footpad reaction (DFR), was rather depressed in these mice because C. parvum-activated macrophages acting as scavenger cells reduced the amount of effective antigenic stimulation. BCG-activated peritoneal macrophages from mice treated i.p. with BCG 14 days previously showed a strong ability for antigen presentation in correlation with increases in the number of Ia-bearing macrophages and in the level of interleukin 1 (IL 1) production. These mice showed an early appearance of DFR response and a markedly enhanced resistance against the listerial infection. These results suggested that the differences in macrophage activities as scavenger cells, cytokine-secreting cells and antigen presenting cells may account for the differences in the responsiveness against listerial infection in peptone-, C. parvum- and BCG-treated mice.

Adjuvants, Immunologic↗
PubMed1990

Tumor necrosis factor and fever at diagnosis in children with solid tumors.

In order to determine the pathogenesis of fever in solid tumors, we studied the association of fever at diagnosis in children with solid tumors (malignant lymphoma, rhabdomyosarcoma, and neuroblastoma), serum levels of interleukin 1 (IL-1), and tumor necrosis factor. Thirteen of 20 patients (65%) with solid tumors were complicated with fever at diagnosis. There was no difference in C-reactive protein or IL-1 levels between the patients with and without fever, while the erythrocyte sedimentation rate and TNF levels were higher in the former than in the latter by Wilcoxon's rank sum test (p less than 0.01). These findings suggest that most febrile episodes at diagnosis in children with solid tumors are associated with the release of tumor necrosis factor.

Acute-Phase Proteins↗