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S Noda

Publications and source records attributed to S Noda.

At least 109 records · Page 6Linked to original sources
PubMed1997

[Clinical and serological study of tsutsugamushi disease in northern Osumi, Kagoshima Prefecture].

We report 34 cases of tsutsugamushi disease seen from 1989 to 1993 at Yagi Clinic, northern Osumi, Kagoshima Prefecture. Nineteen patients (55.9%) showed the highest antibody titers against the Kawasaki strain Orientia tsutsugamushi (Ot) and 13 (38.2%) against the Kuroki strain Ot. It is suggested that two antigenic types (Kawasaki and Kuroki) of Ot were distributed in Kagoshima Prefecture, and the Kawasaki type Ot more or less dominates Kuroki type Ot. There was no difference in clinical features between the two groups of patients.

Adolescent↗
PubMed1997

Effect of piped water supply on human water contact patterns in a Schistosoma haematobium-endemic area in Coast Province, Kenya.

The effect of a piped water supply on human water contact in a Schistosoma haematobium-endemic area in Coast Province, Kenya was studied. After the construction of five community standpipes and one shower unit, there was a 35.1% reduction in the number of people observed using river water, a 44.1% reduction in the frequency of contact with river water, and a 25.4% reduction in the amount of contact. The frequency of river water contact per person also decreased significantly, but the amount of contact per person did not decrease. The total frequency of contact decreased significantly except for washing clothes by the river, washing utensils, and fishing. The frequency per person did not change for most of the activities and significantly increased for washing clothes. The frequency of river water contact in households with high piped water consumption showed a significant decrease compared with those with low piped water consumption. The volume of consumption of piped water was inversely proportional to the distance from the home to the community standpipe. These results indicate that in the study area, the effect of a piped water supply on river water contact behavior was heterologous while the total river water contact decreased significantly, and that the piped water had a beneficial effect on some villagers but very little effect on others.

Adolescent↗
PubMed1997

An outbreak of ascariasis with marked eosinophilia in the southern part of Kyushu District, Japan, caused by infection with swine ascaris.

Ascariasis has been a representative soil-transmitted intestinal parasitic disease in warm climates. In Japan, this disease was a major and serious public health problem only a few decades ago. However, the incidence of the disease nowadays is reportedly less than 0.01%. Recently in 1994 through 1995, we experienced a total of 14 cases who were suspected as having ascariasis. They were characterized by peripheral blood eosinophilia (30-70%), high serum titers against Ascaris antigen, and most notably, they were absolutely negative for Ascaris eggs in repeated fecal examinations. Specific antibody titers against Ascaris antigen correlated well with the degree of eosinophilia. All patients were living in narrow areas of Kyushu, Japan, where a lot of porcine farms were located. Most of the patients were asymptomatic and pointed out to have eosinophilia during follow-up studies of chronic diseases or in regular check-up. Only one patient had a clear sign of Löffler's syndrome and another had subcutaneous eosinophilic granuloma. However, laboratory examinations revealed moderate liver dysfunction in 7 patients and pulmonary infiltrations in 5 patients. Based on circumstantial and serological evidence, these patients were diagnosed as having been infected with Ascaris lumbricoides suum, a swine Ascaris.

Adult↗
PubMed1996

Identification of a novel transmembrane semaphorin expressed on lymphocytes.

Semaphorin (also known as collapsin) members are thought to be involved in axon guidance during neural network formation. Here, we report the isolation of a novel member, mouse semaphorin G (M-sema G), which encodes a semaphorin domain followed by a single putative immunoglobulin-like domain, a transmembrane domain, and a cytoplasmic domain. M-sema G is most closely related to M-sema F, which we previously reported, and semB and semC. These four members appear to constitute a transmembrane type subfamily in mouse semaphorins. In contrast to the predominant expression of M-sema F mRNAs in the nervous tissues, M-sema G mRNAs are strongly expressed in lymphoid tissues, especially in the thymus, as well as in the nervous tissues. The mRNAs are also detected in various cell lines from hematopoietic cells. By generating specific antibodies, we confirmed the strong expression of M-Sema G proteins on the surface of lymphocytes. These results provide the first evidence that semaphorin is expressed on lymphocytes and suggest that semaphorins may play an important role in the immune system, as well as in the nervous system.

Amino Acid Sequence↗
PubMed1996

The mammalian single-minded (SIM) gene: mouse cDNA structure and diencephalic expression indicate a candidate gene for Down syndrome.

We have recently isolated a human homolog (hSIM) of the Drosophila single-minded (sim) gene from the Down syndrome critical region of chromosome 21 using the exon trapping method. The Drosophila sim gene encodes a transcription factor that regulates the development of the central nervous system midline cell lineage. To elucidate the structure of the mammalian SIM protein, we have isolated cDNA clones from a mouse embryo cDNA library. The cDNA clones encode a polypeptide of 657 amino acids with a bHLH (basic-helix-loop-helix) domain, characteristic of a large family of transcription factors, and a PAS (Per-Arnt-Sim) domain in the amino-terminal half region. Both of these domains have striking sequence homology with human SIM and Drosophila SIM proteins. In contrast, the carboxy-terminal half of the mouse SIM protein consists of a proline-rich region with no sequence homology to the Drosophila SIM protein. A similar proline-rich domain is known for the activator domain of a number of transcription factors. Whole-mount embryo in situ hybridization experiments revealed that the SIM mRNA is expressed prominently in the diencephalon of mouse embryos at 8-9.5 days postcoitum. The structural characteristics of the mouse SIM protein and its expression in the diencephalon during embryogenesis strongly suggest that the newly isolated mammalian SIM homolog may play a critical role in the development of the mammalian central nervous system. We propose that the human SIM gene may be one of the pathogenic genes of Down syndrome.

Animals↗
PubMed1996

Protection from anti-TCR/CD3-induced apoptosis in immature thymocytes by a signal through thymic shared antigen-1/stem cell antigen-2.

During T cell development in the thymus, the expression of thymic shared antigen-1 (TSA-1)/stem cell antigen-2 (Sca-2), a glycosylphosphatidylinositol (GPI)-anchored differentiation antigen, is developmentally regulated. The expression level of TSA-1 is the highest in most immature CD4- CD8- thymocytes, high in CD4+ CD8+ thymocytes, but barely detectable in mature CD4+ CD8- or CD4- CD8- thymocytes and peripheral T cells. We have previously shown that surface TSA-1 expression in peripheral T cells is induced upon activation and that anti-TSA-1 mAb inhibits the T cell receptor (TCR) signaling pathway in activated T cells. In the present study, we have analyzed a role of TSA-1 in thymic selection events, especially in TCR-mediated apoptosis. In in vitro experiments, anti-TSA-1 blocked anti-CD3-induced cell death of T cell hybridomas. When anti-TSA-1 was injected into newborn mice in vivo together with anti-CD3 epsilon or anti-TCR-beta, TCR/CD3-mediated apoptosis of thymocytes was almost completely blocked. The blockade of apoptosis was defined by the inhibition of, first, the decrease in total number of thymocytes; second, the decrease in percentages of CD4+ CD8+ thymocytes; and third, the induction of DNA fragmentation. However, anti-TSA-1 did not block either steroid- or radiation-induced apoptosis, indicating that a signal via TSA-1 does not inhibit a common pathway of thymocyte apoptosis. Since TCR-mediated apoptosis is pivotal in thymic ontogeny, these results suggest that TSA-1/Sca-2 is an important cell surface molecule regulating the fate of a developing T cell.

Animals↗
PubMed1996

Population of hepatic macrophages and response of perfused liver to platelet-activating factor during production of thioacetamide-induced cirrhosis in rats.

The response of hepatic macrophages and the effects of platelet-activating factor (PAF) in perfused liver were studied during production of experimental cirrhosis induced by thioacetamide (TAA) in female Sprague-Dawley rats. Within 4 weeks of TAA administration (300 mg/L drinking water), an increase in hepatic macrophage population and enlargement in cell size preceded the alterations characteristic of cirrhosis. During 12 weeks of TAA administration, the changes in hepatic macrophages were maintained and cirrhosis of the micronodular type developed with a marked increase in hydroxyproline content. Although TAA treatment for 4 weeks had no effect on oxygen consumption or hepatic portal pressure in the perfused liver, the increment in hepatic portal pressure and decrement in oxygen consumption induced by PAF in TAA-treated rats were double those in control rats. The amounts of prostaglandin D2 (PGD2) and thromboxane B2 (TxB2) in perfusate induced by PAF were seven- and fivefold greater, respectively, in TAA-treated rats than in control rats. Zymosan mimicked the effects of PAF. These results are consistent with the hypothesis that hepatic macrophages and PAF play important roles in the development of cirrhosis induced by TAA.

Animals↗
PubMed1996

Higher susceptibility of erythropoietin-producing renal cell carcinomas to lysis by lymphokine-activated killer cells.

Erythropoietin production by renal cell carcinoma (RCC) is reported to be a potential marker for interleukin-2/interferon-alpha-responding tumor. We have investigated whether erythropoietin of RCC cells is involved in the immune recognition by lymphokine-activated killer (LAK) cells. Cells from primary culture of RCC cells expressing erythropoietin-mRNA or producing erythropoietin were more susceptible to lysis by LAK cells than those not expressing or producing it, respectively. RCC cells transfected with erythropoietin-cDNA became more susceptible to lysis by LAK cells than their erythropoietin-negative parental cells. These results indicate higher susceptibility of erythropoietin-producing RCC cells to lysis by LAK cells, suggesting that erythropoietin of RCC cells is involved in the immune recognition by LAK cells.

Carcinoma, Renal Cell↗
PubMed1996

Cumulative renal damage in dogs by repeated treatment with extracorporeal shock waves.

BACKGROUND: Extracorporeal shock wave lithotripsy (ESWL) has become a routine method for the treatment of renal and ureteral calculi. Occasionally, multisequential ESWL treatments and high energy shock waves are required to treat large calculi. The purpose of the study was to compare renal histopathologic damage caused by varying the application of shock waves. METHODS: Six groups of dogs were defined by the frequency of shocks, application time and numbers of sessions. Bilateral nephrectomies were performed immediately, 3, 7 and 60 days after the application of shock waves. Histopathologic features of the kidneys were assessed by both light and electron microscopy. RESULTS: Irreversible damage was observed in all exposed kidneys. After a single session of low application frequency, damage by shock waves occurred with progressive deterioration of the nephron. At any frequency rate, the damage was caused by tissue hypoxia due to rupturing of the interstitial capillaries. As the application frequency increased, capillary rupture became more severe, and consequently, morphological damage tended to be more intense. Repeated sessions at any application frequency made the damage more intense, suggesting that an accumulation of damage had occurred. CONCLUSIONS: Minimal doses of shock waves cause renal damage and repeated ESWL sessions may result in an accumulation of damage. Considering that the damage is dose-dependent, divided ESWL treatments at a low frequency rate are advisable in a clinical setting.

Animals↗
PubMed1996

Diversity of Nitrogen Fixation Genes in the Symbiotic Intestinal Microflora of the Termite Reticulitermes speratus.

The diversity of nitrogen-fixing organisms in the symbiotic intestinal microflora of a lower termite, Reticulitermes speratus, was investigated without culturing the resident microorganisms. Fragments of the nifH gene, which encodes the dinitrogenase reductase, were directly amplified from the DNA of the mixed microbial population in the termite gut and were clonally isolated. The phylogenetic analysis of the nifH product amino acid sequences showed that there was a remarkable diversity of nitrogenase genes in the termite gut. A large number of the termite nifH sequences were most closely related to those of a firmicute, Clostridium pasteurianum, with a few being most closely related to either the (gamma) subclass of the proteobacteria or a sequence of Desulfovibrio gigas. Some of the others were distantly related to those of the bacteria and were seemingly derived from the domain Archaea. The phylogenetic positions of these nifH sequences corresponded to those of genera found during a previous determination of rRNA-based phylogeny of the termite intestinal microbial community, of which a majority consisted of new, yet-uncultivated species. The results revealed that we have little knowledge of the organisms responsible for nitrogen fixation in termites.

Journal Article↗
PubMed1996

Unilateral acute posterior multifocal placoid pigment epitheliopathy.

A 24-year-old woman complained of paracentral scotomas in her left eye. Her visual acuity was good bilaterally. Multifocal, creamy, yellow-white lesions were seen at the level of the pigment epithelium and choroid in the left fundus. Fluorescein angiography showed blockage at the early phase and hyperfluorescence at the late phase in the left eye. The right fundus remained normal during the follow-up period of 1 year. We believe that unilateral acute posterior multifocal placoid pigment epitheliopathy, as found in our patient, may be uncommon.

Acute Disease↗
PubMed1996

[Assessment of thalamic regional cerebral blood flow in patients with cerebrovascular disease].

The thalamus is believed to play an integrative role in the central nervous system. In the present study, thalamic rCBF was measured in 65 CVD patients and 15 normal volunteers by stable Xe/CT scanning. ROIs were chosen in the thalamic slice at a level 5cm over the OM line, and mean CBF was 7 cm over the OM line. The clinical factors focused on in multiple regression analysis were: age (A), sex (Se), stage from onset (St), lesion side (Sd); unilaterality or bilaterality, size (Sz) thalamic lesion (Tl). GCS (G), HDS-R (H); Hasegawa dementia score (revised), symptoms (Ss) such as anxiety, dizziness, head-headed feeling and headache, and neurological deficits (N). Each factor was graded and scored. Statistically, there was a significant correlation between thalamic rCBF (Y) and mean CBF (X) in the less affected hemisphere: Y = 1.82X + 2.2, r = 0.801, p < 0.001, n = 65. Multiple regression analysis of the thalamic rCBF revealed that the Sz factor was significant (p < 0.0001) on the lesion side: Y = 76.7-10.2Sz, r = 0.644, p < 0.001, n = 51, while the Se, Sd and St factors were significant (p < 0.005) on the less affected side: Y = 71.9 + 9.7Se-6.8Sd-5.0St, R = 0.585, p < 0.001, n = 65. The thalamic index (X), an indicator of thalamic atrophy, and thalamic rCBF were significantly correlated: Y = 28.7X + 10.2, r = 0.386, p < 0.001, n = 80. In conclusion, thalamic rCBF appeared to reflect the degree of organic changes and time course in the cerebral hemisphere, because factors such as size, sex and stage were statistically significant.

Cerebral Infarction↗
PubMed1995

Modulation of TCR-mediated signaling pathway by thymic shared antigen-1 (TSA-1)/stem cell antigen-2 (Sca-2).

Thymic shared antigen-1 (TSA-1) is a glycosyl-phosphatidylinositol (GPI)-anchored differentiation Ag expressed on murine lymphocytes, and is identical to stem cell Ag-2 (Sca-2). Using newly established mAb against TSA-1/Sca-2, we have previously shown that surface TSA-1 expression is induced upon activation in T cells, and that anti-TSA-1 inhibits IL-2 production induced by anti-CD3 stimulation in T cell hybridomas. In the present study, we have analyzed the functional role of TSA-1 during T cell activation using normal T cells, T cell hybridomas, and transfected Jurkat cell lines that expressed either GPI-anchored or transmembrane form of TSA-1. Anti-TSA-1 inhibited IL-2 production from normal T cells stimulated with soluble anti-CD3 plus accessory cells. Anti-TSA-1 exhibited the inhibitory effect on T cells, but not on accessory cells, because anti-TSA-1 inhibited IL-2 production in Jurkat cells transfected with TSA-1 cDNA, but not in control transfectant. A transmembrane form of TSA-1 was expressed in Jurkat cells by fusing the extracellular portion of TSA-1 to the transmembrane and cytoplasmic regions of the class 1 Db. The analysis using this transfectant revealed that anti-TSA-1-mediated inhibition of IL-2 production did not require the GPI anchor of TSA-1. Finally, in addition to the inhibition of IL-2 production, tyrosine phosphorylation of CD3 zeta-chains observed following TCR stimulation, one of the important early activation events, was markedly reduced by anti-TSA-1. These results imply that TSA-1/Sca-2 plays an important regulatory role in the TCR signaling pathway of activated T cells in addition to its role in T cell differentiation.

Animals↗
PubMed1995

Phylogeny of symbiotic methanogens in the gut of the termite Reticulitermes speratus.

The phylogeny of a symbiotic methanogen inhabiting the gut of a lower termite. Reticulitermes speratus, was analysed without cultivation. The small subunit ribosomal RNA gene (ssrDNA) and a 640-bp portion of the gene encoding subunit A of methyl coenzyme M reductase (mcrA) were amplified from a mixed-population DNA of the termite gut by polymerase chain reaction and cloned. The nucleotide sequence of the ssrDNA and the predicted amino acid sequence of the mcrA product were compared with those of the known methanogens. Both comparisons indicated that the termite symbiotic methanogen belonged to the order Methanobacteriales but was distinct from the known members of this order.

Animals↗
PubMed1995

Regulatory mechanisms for production of IFN-gamma and TNF by antitumor T cells or macrophages in the tumor-bearing state.

Spleen cells from BALB/c mice bearing a syngeneic tumor (CSA1 M) 2 to 3 wk after inoculation with CSA1 M cells produced IL-2, IFN-gamma, and TNF upon in vitro cultures. This was previously demonstrated to be a result of collaboration between tumor-primed CD4+ T cells and APCs binding CSA1 M tumor Ags in vivo. The IL-2- and IFN-gamma-producing capacities decreased with the progress of tumor-bearing stages. This was parallel to the levels of IL-2 and IFN-gamma mRNAs expressed by cultured spleen cells. In contrast, comparable levels of TNF mRNA were expressed by all groups of cultured cells. However, large amounts of TNF were secreted by the cells from early but not from late tumor-bearing mice. TNF was produced mainly by the non-T cell fraction upon stimulation with CD4+ T cell-derived IFN-gamma. Therefore, the reduced TNF production by whole spleen cells from late tumor-bearing mice was restored by addition of rIFN-gamma to their cultures. Reciprocally to the progressive decrease in the production of IFN-gamma/TNF, the capacities of tumor-bearing mice to produce TGF-beta and IL-6 increased along with tumor growth. TGF-beta suppressed production of IL-2, IFN-gamma, and TNF, but not of IL-6. Moreover, IFN-gamma/TNF production was negatively regulated by IL-6. Taken together with the fact that the growth of CSA1 M cells is completely inhibited by the combination of TNF and IFN-gamma, these results demonstrate that the tumor-bearing state induces an abnormal cytokine network under which the production of antitumor cytokines is negatively regulated.

Animals↗
PubMed1995

Primary malignant melanoma of the biliary tract.

Primary malignant melanoma of the biliary tract is an obscure entity, with only four previously reported cases. We report two cases involving the common bile duct. A 43-year-old male who underwent a right hepatectomy and excision of the extrahepatic biliary tree for a lesion at the bifurcation of the common bile duct. He remains alive and well 11 months after resection. The second patient is a 45 year old male with obstructive jaundice due to an ampullary lesion. Pancreaticoduodenectomy was performed with no signs of metastatic disease. He is 6 years following resection without evidence of disease. This is an unusual cause of obstructive jaundice and a definitive search for a possible extra-biliary primary should be pursued. In appropriately selected patients without evidence of metastatic disease, resection can potentially afford long-term survival if these lesions are true primary lesions and not metastatic from an undefined primary. However, given the high metastatic potential of melanoma it is unclear whether resection of these lesions results in cure or just effective long-term palliation.

Adult↗