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S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 325 records · Page 18Linked to original sources
PubMed1999

[Elastase anti-elastase imbalance in the pathogenesis of COPD].

Elastase anti-elastase imbalance theory is most important in the pathogenesis of COPD (pulmonary emphysema). Proteolytic activity of neutrophil elastase (NE) plays an important role because of the detachment of cells through proteolysis of extracellular matrix. In addition to proteolytic activity of NE, NE-induced activation of intracellular signaling (MAPK(Erk), Rho and MLCK) participates in NE-induced morphological changes in airway epithelial cells.

Disease Progression↗
PubMed1999

[A case of glomangioma of the stomach].

Glomus tumor of the stomach is still a rare disease. In Japan, till now, only 78 cases have been reported as far as we look over the literatures. We report a case of glomangioma of the stomach. The patient is a 44-years old female who underwent a medical examination and pointed out a gastric submucosal tumor, but she had no symptoms and admitted for operation. The endoscopical finding was a submucosal tumor as large as 4 cm, and the result of biopsy was chronic atrophic gastritis. So typical gastrectomy was performed without a definite diagnosis. In the cross section, the tumor was clearly bounded gastric mucosa by a white membrane, and the center of the tumor was spongy. By patho-histological and electro-microscopic study, we diagnosed that the tumor was glomangioma in the classification of Weiss & Enzinger. The patient was getting on well after the operation and left the hospital on the 29th day.

Adult↗
PubMed1999

[Contrast medium injection on CT during hepatic arteriography: comparison of two protocols].

To assess the optimum method of contrast medium injection on CT during hepatic arteriography (CTHA), we performed this procedure in 37 patients using two consecutive protocols (A and B) employing different concentrations of iodine (iohexol at 140 mgI/ml and 300-350 mgI/ml), flow rates (2 ml/sec and 1 ml/sec), and contrast medium volumes (60 ml and 30 ml). Mean parenchymal enhancement of the right lobe and left lateral segment were measured and compared. Enhancement varied significantly more with protocol B, especially in the left lateral segment. These results suggest that a low iodine concentration and high injection rate are suitable for CTHA, to avoid nonuniform parenchymal enhancement.

Adult↗
PubMed1999

[Subcutaneous phaeohyphomycosis of the right thumb].

Black fungi are a group of fungi that are characterized by the development of a pale brown to black color in the cell walls of their vegetative cells, conidia, or both. A mycotic infection caused by a member of black fungi can be subdivided into three clinical entities: phaeohyphomycosis, chromoblastomycosis, and mycetoma. Phaeohyphomycosis is distinguished from mycetoma by the absence of grain (organized, interwoven mycelial aggregates) formation, and from chromoblastomycosis by the absence of sclerotic bodies (thick-walled muriform cells). Phaeohyphomycosis is a rare disease and has been sporadically reported. In the present report, phaeohyphomycosis of the right thumb of a 72-year-old man was presented. A precipitating trauma of two months earlier at the site was recalled. A solitary mass, 10 mm in diameter, was gradually formed in the palm side of the distal right thumb and finally resected. Histological examination disclosed a solitary granulomatous lesion surrounded by an incomplete fibrous capsule. The lesion mainly involved subcutaneous tissue and was composed of multiple pyogranulomas. Pigmented branched septate hyphae and yeast-like cells were sparsely found in the periphery of the abscess and within histiocytic cells of the granulomas. No sclerotic cells were detected. When pigmentation of black fungi in tissue is as faint as in the present case, Fontana-Masson staining is useful to accentuate the presence of melanin-like pigment of fungal cell walls.

Aged↗
PubMed1999

[Distributions of the numbers of monitoring stations in the surveillance of infectious diseases in Japan].

To describe the characteristics of monitoring stations for the infectious disease surveillance system in Japan, we compared the distributions of the number of monitoring stations in terms of population, region, size of medical institution, and medical specialty. The distributions of annual number of reported cases in terms of the type of diseases, the size of medical institution, and medical specialty were also compared. We conducted a nationwide survey of the pediatrics stations (16 diseases), ophthalmology stations (3 diseases) and the stations of sexually transmitted diseases (STD) (5 diseases) in Japan. In the survey, we collected the data of monitoring stations and the annual reported cases of diseases. We also collected the data on the population, served by the health center where the monitoring stations existed, from the census. First, we compared the difference between the present number of monitoring stations and the current standard established by the Ministry of Health and Welfare (MHW). Second, we compared the distribution of all medical institutions in Japan and the monitoring stations in terms of the size of the medical institution. Third, we compared the average number of annual reported cases of diseases in terms of the size of medical institution and the medical specialty. In most health centers, the number of monitoring stations achieved the current standard of MHW, while a few health centers had no monitoring station, although they had a large population. Most prefectures also achieved the current standard of MHW, but some prefectures were well below the standard. Among pediatric stations, the sampling proportion of large hospitals was higher than other categories. Among the ophthalmology stations, the sampling proportion of hospitals was higher than other categories. Among the STD stations, the sampling proportion of clinics of obstetrics and gynecology was lower than other categories. Except for some diseases, it made little difference in the average number of annual reported cases of diseases in terms of the type of medical institution. Among STD, there was a great difference in the average number of annual reported cases of diseases in terms of medical specialty.

Child↗
PubMed1999

[Determination of the numbers of monitoring medical institutions necessary for estimating incidence rates in the surveillance of infectious diseases in Japan].

Our purpose was to determine the number of monitoring stations (medical institutions) necessary for estimating incidence rates in the surveillance system of infectious diseases in Japan. Infectious diseases were selected by the type of monitoring stations: 15 diseases in pediatrics stations, influenza in influenza stations, 3 diseases in ophthalmology stations and 5 diseases in the stations of sexually transmitted diseases (STD). For each type of monitoring station, 5 cases of the number of monitoring stations in each health center, including the number determined from presently established standards and the actual number in 1997, were given. It was assumed that monitoring stations were randomly selected among medical institutions in health centers. For each infectious disease, each case and each type of monitoring station, standard error rates of estimated numbers of incidence cases in the whole country were calculated in 1993-1997 using the data of the surveillance of infectious diseases. Among 5 cases of monitoring stations, the case satisfied the condition that those standard error rates were lower than the critical values, was selected. The critical values were 5% in pediatrics and influenza stations, and 10% in ophthalmology and STD stations. The numbers of monitoring stations in the selected cases were 3,000 in pediatrics stations, 5,000 in influenza stations (including all pediatrics stations), 605 in ophthalmology stations and 900 in STD stations.

Child↗
PubMed1998

Chronic lymphocytic leukemia B cells express restricted sets of mutated and unmutated antigen receptors.

To better understand the stage(s) of differentiation reached by B-type chronic lymphocytic leukemia (B-CLL) cells and to gain insight into the potential role of antigenic stimulation in the development and diversification of these cells, we analyzed the rearranged VH genes expressed by 83 B-CLL cells (64 IgM+ and 19 non-IgM+). Our results confirm and extend the observations of a bias in the use of certain VH, D, and JH genes among B-CLL cells. In addition, they indicate that the VH genes of approximately 50% of the IgM+ B-CLL cells and approximately 75% of the non-IgM+ B-CLL cells can exhibit somatic mutations. The presence of mutation varies according to the VH family expressed by the B-CLL cell (VH3 expressers displaying more mutation than VH1 and VH4 expressers). In addition, the extent of mutation can be sizeable with approximately 32% of the IgM+ cases and approximately 68% of the non-IgM+ cases differing by > 5% from the most similar germline gene. Approximately 20% of the mutated VH genes display replacement mutations in a pattern consistent with antigen selection. However, CDR3 characteristics (D and JH gene use and association and HCDR3 length, composition, and charge) suggest that selection for distinct B cell receptors (BCR) occurs in many more B-CLL cells. Based on these data, we suggest three prototypic BCR, representing the VH genes most frequently encountered in our study. These data suggest that many B-CLL cells have been previously stimulated, placing them in the "experienced" or "memory" CD5(+) B cell subset.

Amino Acid Sequence↗
PubMed1998

In vivo effects of pioglitazone on uncoupling protein-2 and -3 mRNA levels in skeletal muscle of hyperglycemic KK mice.

Pioglitazone is a thiazolidinedione drug (TZD) which potently and specifically stimulates peroxisome proliferator-activated receptor gamma (PPAR gamma) and sensitizes cells to insulin. Since TZDs are thought to increase energy expenditure, changes in mitochondrial thermogenesis uncoupling protein-2 and -3 mRNA levels in response to pioglitazone treatment were measured in mouse skeletal muscle. Normally hyperglycemic and hyperinsulinemic KK/Ta mice were given pioglitazone for 2 weeks to treat this non-insulin dependent diabetes-like condition. During treatment, UCP2 mRNA levels increased to 185% of normal untreated control levels in soleus muscle. In contrast, UCP3 mRNA levels significantly decreased, up to 67% of normal untreated control levels. Interestingly, UCP3 mRNA levels correlated quite strongly with blood glucose levels, with r = 0.82 for gastrocnemius tissue and r = 0.92 for soleus tissue. These results may indicate that pioglitazone increases glucose catabolism by direct upregulation of muscle UCP2 gene expression in vivo. Therefore, UCP3 gene expression is controlled by a different mechanism than UCP2 expression.

Animals↗
PubMed1998

The attenuated effect of ATP-sensitive K+ channel opener pinacidil on renal haemodynamics in spontaneously hypertensive rats.

In hypertension, impairment of hyperpolarization by K+ efflux through ATP-sensitive K+ (K(ATP)) channels may contribute to the elevated renal vascular resistance. To elucidate such a role for K(ATP) channels in the renal vasculature, we used micropuncture techniques to examine the effect of K(ATP) channel opener, pinacidil (0.15 mg/h per kg body wt i.v.), on renal and glomerular haemodynamics in spontaneously hypertensive rats (SHR) and in normotensive controls (Wistar Kyoto, WKY). Since pinacidil reduced blood pressure significantly in both groups, the abdominal aorta was clamped before pinacidil administration to yield a renal perfusion pressure equivalent to that during pinacidil infusion. Pinacidil significantly decreased renal vascular resistance in both groups, but the relative change from baseline value was greater in WKY than in SHR. These effects of pinacidil were abolished by pretreatment with glibenclamide (3 mg/kg body wt i.v.). Proximal tubular stop-flow pressure (Psf), an index of glomerular capillary pressure, was significantly elevated by pinacidil infusion in WKY, a response abolished by pretreatment with glibenclamide, but not in SHR. The tubuloglomerular feedback response of Psf was not affected by pinacidil in either group. These data suggest that the activity of K(ATP) channels in SHR may be attenuated in the renal microvasculature. This may contribute to the elevated vascular tone in the renal preglomerular vasculature in SHR.

Animals↗
PubMed1998

Presence of dioxins in human follicular fluid: their possible stage-specific action on the development of preimplantation mouse embryos.

Examination of human follicular fluid revealed the presence of polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs) at concentrations of approximately 1 pg/ml (0.01 pg TEQ/ml). To study their possible action, two-cell mouse embryos were cultured in the presence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at concentrations between 0.5 and 100 pM and evaluated at 24-h intervals for their development to the eight-cell and blastocyst stages. The percentage of eight-cell embryos exposed to TCDD at 1, 2, and 5 pM concentrations was significantly lower than that of controls. However, blastocyst formation of the surviving eight-cell embryos was accelerated, with the number of cells in the blastocysts increased in a dose-dependent manner. Findings suggest that PCDDs and PCDFs may be present in human reproductive fluid and may exert some stage-specific effects on early embryonic development.

Animals↗
PubMed1998

Translocation of Arf1 to the secretory granules in rat parotid acinar cells.

We investigated the interaction of ADP-ribosylation factor (Arf) with the secretory granules in rat parotid acinar cells. The 20. 5-kDa small-molecular-mass GTP-binding protein in the cytosolic fraction of rat parotid acinar cells was identified as ADP-ribosylation factor1 by using a pan-Arf monoclonal antibody and isotype-specific polyclonal antibodies for Arf proteins 1, 3, 5, and 6. Incubation of the cytosolic fraction with isolated secretory granule membranes in the presence of GTPgammaS resulted in the translocation of Arf1 from the cytosolic fraction to the secretory granule membranes. The translocation was not observed in the presence of GDPbetaS in place of GTPgammaS, indicating that the process is GTP-dependent. The immunoelectron microscopy experiment confirmed Arf1 is translocated to the secretory granules. A prior treatment of the granule membranes with trypsin inhibited the translocation of Arf1 at 2 mM Mg2+, but had no effect in the absence of Mg2+ (condition of spontaneous conversion of Arf-GDP to Arf-GTP). Thus, the trypsin-sensitive nucleotide exchange activity for Arf1 is probably associated with the secretory granule membranes. These results demonstrate Arf1 translocates to the secretory granules in rat parotid acinar cells.

ADP-Ribosylation Factor 1↗
PubMed1998

Paxillin isoforms in mouse. Lack of the gamma isoform and developmentally specific beta isoform expression.

Paxillin, a focal adhesion protein, exists as multiple isoforms in humans (alpha, beta, and gamma). To understand more about the physiological role of each isoform, we have employed the mouse system. We found that although the alpha and beta isoforms are present in the mouse, the gamma isoform is not. The alpha isoform protein was detected clearly in most adult tissues, whereas the beta isoform protein was almost undetectable except in spleen, testis, thymus, and lung. On the other hand, mRNAs of both isoforms were detectable in all tissues we examined. High levels of the beta isoform protein was detected in peritoneal exudate macrophage cells in adult mouse as well as in cultured fibroblasts, together with the alpha isoform. The alpha isoform was expressed at a constant level throughout the embryonic stages we examined, whereas the beta isoform protein was detected at the mid-stages of development and increased to levels almost equal to those of the alpha isoform during the late stages of embryogenesis. Therefore, unlike the alpha isoform, expression of the beta isoform protein is restricted in adult tissues. Moreover, we showed that alpha and beta isoforms were colocalized within the same focal adhesion plaques, and cytoplasmic pools of both isoforms exist in the perinuclear area, colocalized with the Golgi apparatus.

3T3 Cells↗
PubMed1998

Cooling and rewarming-induced IL-8 expression in human bronchial epithelial cells through p38 MAP kinase-dependent pathway.

p38 mitogen-activated protein kinase (MAP) kinase is activated by various stresses; however, little is known about cold stress which has been shown to cause various inflammatory diseases. In the present study, we examined the effect of cold stimulation on interleukin-8 (IL-8) expression and a role of p38 MAP kinase in IL-8 expression in human bronchial epithelial cells (BEC) in order to clarify the mechanism in hypothermic temperature-induced inflammation. The results showed that cold stimulation induced tyrosine phosphorylation of p38 MAP kinase but not IL-8 expression. IL-8 expression in BEC was induce when the temperature of incubation changed from 1 degree C to 37 degrees C (cooling and rewarming). The specific p38 MAP kinase inhibitor SB 203580 inhibited cooling and rewarming-induced IL-8 expression, indicating that cooling and rewarming-induced IL-8 expression in BEC was mediated through p38 MAP kinase-dependent pathway.

Bronchi↗
PubMed1998

Cloning of the TIS gene suppressed by topoisomerase inhibitors.

We recently cloned the cDNA TIS (topoisomerase inhibitor-suppressed) in RVC lymphoma cells exposed to the topoisomerase inhibitors. To elucidate the suppression mechanism of the TIS mRNA by camptothecin, we characterized the structures of the TIS gene. The gene spanned about 21 kb including 11 exons and was present as a single copy. The putative transcription site was present 192 bp upstream from the ATG codon. The typical TATA sequence and CCAAT promoter element were located at positions -21 and -81, respectively. The unidirectional deletion analysis of the 5'-flanking region revealed that [-132/+160] is the promoter region, which participates in the responsiveness to camptothecin. A Northern blot analysis showed that the TIS was expressed in most mouse tissues; at the highest level in the liver and to less extent in the heart and skeletal muscle. The present study showed that the expression of the TIS is suppressed at the transcriptional level by camptothecin. Considering that topoisomerase I is an essential enzyme in mammalian cells, the TIS protein may have an important role in camptothecin toxicity.

Amino Acid Sequence↗
PubMed1998

Cloning of PCPTP1-Ce encoding protein tyrosine phosphatase from the rat cerebellum and its restricted expression in Purkinje cells.

Recently, cDNAs encoding brain-specific transmembrane-type protein tyrosine phosphatases (PTPs) with single catalytic domain have been cloned. These include PC12-PTP, PCPTP1, PTPBR7, and PTP-SL, whose cytoplasmic domains had high similarity to STEP, a brain-specific nontransmembrane-type PTP. Based on the high similarity and expression pattern, PCPTP1 seems to be identical with PC12-PTP1 and to be the rat homologue of murine PTPBR7. Here, we report the molecular cloning and expression profile of PCPTP1-Ce, a variant of PCPTP1. Both PCPTP1 mRNA and PCPTP1-Ce mRNA seem to be derived from a single common region gene. Nucleotide and deduced amino acid sequence comparison between PCPTP1-Ce and PCPTP1 revealed that the predicted protein product of PCPTP1-Ce is identical with that translated from the third initiation methionine of the longest ORF of PCPTP1, and that these two clones differ in the 5'-untranslated sequences. Northern blot analyses with specific probes for PCPTP1 and PCPTP1-Ce confirmed our previous observation that PCPTP1-Ce mRNA was almost exclusively expressed in the cerebellum, whereas PCPTP1 was widely expressed in various brain regions dissected including cerebellum. In situ hybridization study demonstrated that PCPTP1-Ce mRNA was exclusively expressed in Purkinje cells of the cerebellum. In contrast, PCPTP1 mRNA was predominantly expressed in granule cells and less in Purkinje cells. Moreover, immunohistochemical analysis using an affinity-purified polyclonal antibody raised against the cytoplasmic region of PCPTP1/PCPTP1-Ce demonstrated that Purkinje cells were strongly immunostained, whereas granule cells were stained only faintly in the cerebellum. These observations clearly demonstrated that PCPTP1-Ce mRNA and its protein products are expressed in Purkinje cells and suggest that PCPTP1-Ce may play an important role in Purkinje cell function in the rat cerebellum.

Animals↗
PubMed1998

Bovine lactoferrin stimulates the phagocytic activity of human neutrophils: identification of its active domain.

Bovine LF (bLF) at concentrations in the range of 50-250 micrograms/ml enhanced the phagocytic activity of human neutrophils as determined by measuring the incorporation of FITC-labeled latex beads by flow cytometry. The stimulatory effect of bLF was not abrogated by hydrolysis with pepsin. Bovine lactoferricin (bLFcin), which is a bactericidal fragment purified from a pepsin hydrolysate of bLF (bLFH), also enhanced the phagocytic activity, whereas, in contrast, the fraction of bLFH depleted of bLFcin showed no stimulatory effect. The phagocytosis-enhancing activity of bLF still remained after washing the neutrophils, following exposure to bLF. Also, bLF pretreatment of the latex beads stimulated their uptake. These results demonstrate that bLF is effective in promoting the phagocytic activity of human neutrophils. This activity appears to be due to its bLFcin domain and may involve dual mechanisms of direct binding to neutrophils and opsonin-like activity.

Animals↗
PubMed1998

Bifurcated dendritic cell differentiation in vitro from murine lineage phenotype-negative c-kit+ bone marrow hematopoietic progenitor cells.

We have recently established the culture system to generate dendritic cells (DCs) from murine Lin-c-kit+ bone marrow hematopoietic progenitor cells (HPCs) in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) + stem cell factor (SCF) + tumor necrosis factor-alpha (TNF-alpha). We present here the identification of two DC precursor subsets originated from HPCs with the phenotype of CD11b-/dullCD11c+ and CD11b+hiCD11c+ that develop independently at early time points (days 4 to 6) in the same culture conditions. Both of CD11b-/dullCD11c+ and CD11b+hiCD11c+ precursors could differentiate at day 10 to 14 into CD11b-/dullCD11c+ mature DCs with typical morphology, phenotype, and the ability to stimulate allogenic mixed leukocyte reaction (MLR). However, the endocytic capacity of fluorescein isothiocyanate-dextran was markedly reduced during the differentiation. CD11b-/dullCD11c+ precursors expressed high levels of Ia, CD86, CD40, and E-cadherin molecules, but not c-fms transcript, and mature DCs derived from this precursor subset continue to express abundant E-cadherin antigen, a discernible marker for Langerhans cells. In contrast, CD11b+hiCD11c+ precursors expressed c-fms mRNA, but low levels of Ia, CD86, and E-cadherin, whereas CD40 was undetectable. CD11b-/dullCD11c+ mature DCs differentiated from these precursors displayed abundant c-fms mRNA and nonspecific esterase activity. Interestingly, CD11b+hiCD11c+ precursors, but not CD11b-/dullCD11c+ precursors, may be bipotent cells that can be induced by M-CSF to differentiate into macrophages. All of these results suggest that CD11b-/dullCD11c+ and CD11b+hiCD11c+ cells are distinct DC precursors derived from Lin-c-kit+ HPCs, which differentiate into mature DCs through bifurcated and independent DC differentiation pathways.

Animals↗