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S Hashimoto

Publications and source records attributed to S Hashimoto.

At least 523 records · Page 29Linked to original sources
PubMed1996

Maternal dexamethasone treatment enhances the expression of surfactant apoprotein A in the hypoplastic lung of rabbit fetuses induced by oligohydramnios.

Previously the authors reported that oligohydramnios induced lung hypoplasia in rabbit fetuses and showed that sustained oligohydramnios, which was induced by amniotic shunting from gestational sacs into the maternal peritoneal cavity between 23 and 30 days' gestation, significantly retards not only lung structural growth but also the functional development of alveolar type II cells in surfactant apoprotein A (SP-A) expression. In the present study, the authors examined, both immunohistochemically and morphometrically, whether the maternal administration of dexamethasone restored SP-A synthesis in fetal hypoplastic lungs. The fetal rabbits were treated through maternal administration of dexamethasone (0.25 mg/kg/d) or saline 48 and 24 hours before delivery, at 30 days' gestation. The ratio of lung weight to body weight was significantly greater for the dexamethasone-treated fetuses compared with the saline-treated fetuses in both the shunted and the nonshunted groups (P < .05). Compared with the lungs of the saline-treated fetuses, those of the dexamethasone-treated fetuses had a statistically significant increase in SP-A expression, namely the number of SP-A-positive type II cells per unit area (P < .001), the ratio of SP-A-positive cells to the total number of cells (P < .01), and the percentage of SP-A-positive area per unit area (P < .05) in the shunted group. An increase in the ratio of SP-A-positive area to lung interstitial was found for the shunted group. However, similar findings were not observed in the nonshunted group. The results suggest that maternal dexamethasone treatment accelerates the functional development of alveolar type II cells in SP-A expression, even in hypoplastic lungs induced by oligohydramnios.

Animals↗
PubMed1996

ZTTA, a postproline cleaving enzyme inhibitor, improves cerebral ischemia-induced deficits in a three-panel runway task in rats.

We investigated the effect of N-benzyloxycarbonyl-thioprolyl-thioprolinal-dimethylaceta l (ZTTA), a novel postproline cleaving enzyme (prolyl endopeptidase, PPCE) inhibitor, on the in vitro activity of rat brain PPCE and memory impairment induced by cerebral ischemia. ZTTA noncompetitively inhibited rat brain PPCE (ki = 2.9 microM). Cerebral ischemia for 5 min increased the number of errors in a working memory task with a three-panel runway paradigm. ZTTA at 6 mg/kg, administered immediately after blood flow reperfusion, significantly reduced the increase in working memory errors expected to occur 24 h after 5 min of ischemia. The antiamnesic action of ZTTA may be ascribable to a neuroprotective effect on the central nervous system due to some neuropeptides that are substrates of PPCE in the brain.

Animals↗
PubMed1996

Effects of footshock stress on regional brain monoamine metabolism and the acquisition of conditioned freezing in rats previously exposed to repeated methamphetamine.

1. Effects of footshock stress on regional brain DA and 5-HT metabolism and the acquisition of conditioned fear in male Wistar-King rats previously exposed to repeated MA were examined. 2. MA-pretreated rats exhibited more freezing than control rats in the conditioned fear test. 3. The HVA levels in the striatum was elevated by footshock only in MA-treated rats but not saline-treated rats. Furthermore, MA-treated rats showed increased metabolism of DA in the mPFC, even when placed in the shock chamber without shocks. 4. The brain serotonergic responsiveness to fear conditioning was also attenuated by repeated administration of MA. 5. These results suggest that not only the brain DA systems but also the brain 5-HT systems play an important role for the development of MA-induced emotional hypersensitivity to stress.

Animals↗
PubMed1996

A full genome search in multiple sclerosis.

The aetiology of multiple sclerosis (MS) is uncertain. There is strong circumstantial evidence to indicate it is an autoimmune complex trait. Risks for first degree relatives are increased some 20 fold over the general population. Twin studies have shown monozygotic concordance rates of 25-30% compared to 4% for dizygotic twins and siblings. Studies of adoptees and half sibs show that familial risk is determined by genes, but environmental factors strongly influence observed geographic differences. Studies of candidate genes have been largely unrewarding. We report a genome search using 257 microsatellite markers with average spacing of 15.2 cM in 100 sibling pairs (Table 1, data set 1 - DS1). A locus of lambda>3 was excluded from 88% of the genome. Five loci with maximum lod scores (MLS) of >1 were identified on chromosomes 2, 3, 5, 11 and X. Two additional data sets containing 44 (Table 1, DS2) and 78 sib pairs (Table 1, DS3) respectively, were used to further evaluate the HLA region on 6p21 and a locus on chromosome 5 with an MLS of 4.24. Markers within 6p21 gave MLS of 0.65 (non-significant, NS). However, D6S461, just outside the HLA region, showed significant evidence for linkage disequilibrium by the transmission disequilibrium test (TDT), in all three data sets (for DS1 chi2 = 10.8, adjusted P < 0.01)(DS2 and DS3 chi2 = 10.9, P < 0.0005), suggesting a modest susceptibility locus in this region. On chromosome 5p results from all three data sets (222 sib pairs) yielded a multipoint MLS of 1.6. The results support genetic epidemiological evidence that several genes interact epistatically to determine heritable susceptibility.

Chromosome Mapping↗
PubMed1996

Elevation of plasma-soluble tumour necrosis factor receptors (TNF-R) in sarcoidosis.

Two types of receptor for tumour necrosis factor-alpha (TNF-R), the 55-kD receptor (TNF-RI) and the 75-kD receptor (TNF-RII), have been identified. Soluble TNF-RI (sTNF-RI) and soluble TNF-RII (sTNF-RII) can be measured in culture supernatants and biological fluids, and the role of sTNF-R has been suggested. In the present study, we measured plasma sTNF-RI and sTNF-RII levels in 19 patients with active sarcoidosis by ELISA in order to assess the state of both types of receptors in this disease. Both plasma sTNF-RI and sTNF-RII levels in patients with active sarcoidosis were significantly higher than those in normal control subjects. A longitudinal evaluation of plasma sTNF-RI and sTNF-RII levels showed that the magnitude of changes in sTNF-RII was closely related with the clinical course of sarcoidosis. These results suggest that plasma sTNF-RII levels may be useful parameters for monitoring the clinical course of sarcoidosis as well as markers for identifying disease activity.

Adult↗
PubMed1996

Elevation of serum soluble tumour necrosis factor (TNF) receptor and IL-1 receptor antagonist levels in bronchial asthma.

The specific inhibitor for TNF-alpha activity, soluble form of the 55-kD TNF receptor (sTNF-RI) and soluble form of the 75-kD receptor (sTNF-RII), and the specific inhibitor for IL-1 activity, IL-1 receptor antagonist (IL-1Ra), have been identified. It has been shown that the levels of these inhibitors are elevated in plasma/serum and biological fluids in several diseases, and the protective and inhibitory effect of these inhibitors exist in several inflammatory diseases. In the present study, we measured serum levels of sTNF-RI, STNF-RII and IL-1Ra by ELISA in 36 patients with bronchial asthma (16 atopic and 20 non-atopic) during asthma attacks and in stable conditions in order to assess the state of these inhibitors in allergic inflammation. The levels of sTNF-RI, sTNF-RII and IL-1Ra in sera obtained during bronchial asthma attacks were higher than those in sera obtained in stable conditions. These findings were obtained regardless of atopic status. These results suggest that higher levels of serum sTNF-RI, sTNF-RII and IL-1Ra may reflect up-regulation of TNF-R expression and IL-1Ra production in allergic inflammation, and sTNF-RI, sTNF-RII and IL-1Ra may contribute to regulating TNF-alpha- and IL-1-mediated production and development of allergic inflammation.

Adult↗
PubMed1996

Connexin expression in the salivary glands.

To investigate the ultrastructure of gap junctions and functional differences between connexin (gap junction structural protein) 32 and 43 in the rat submandibular and sublingual glands, tracer and freeze-fracture methods were carried out, and the expression of both connexins was examined. In both glands, western blot analysis with anti-connexin 32 and 43 antibodies revealed bands of about 27kD and 43kD, respectively. Immunofluorescence showed the presence of connexin32-positive spots between acinar cells in both glands. In contrast, connexin43-positive spots were observed at the periphery of the acinar structures in either gland. Positive spots for both connexins could not be detected between ductal cells in both glands. By immunocytochemistry, connexin32 was found on the gap junctional membranes of acinar cells and connexin43 on the gap junctional membranes of myoepithelial cells. It is surmised that connexin32 of the gap junction is related to the secretory function of acinar cells and that connexin43 is associated with the contraction of the myoepithelial cells.

Animals↗
PubMed1996

Phenotypic change and proliferation of murine Kupffer cells by colony-stimulating factors.

Kupffer cells were isolated from C57BL/6 mice by collagenase perfusion and assessed for response to colony-stimulating factors (CSFs) in terms of their phenotypic change and proliferation. Kupffer cells expressed F4/80, but not Mac-1, CD71, or asialo-GM1 initially. This phenotype pattern was different from that of alveolar and peritoneal macrophages. After stimulation with recombinant human macrophage CSF (M-CSF) or mouse granulocyte-macrophage CSF (GM-CSF), Kupffer cells expressed Mac-1 and a low level of CD71 in addition to F4/80 and increased in phagocytotic activity in association with the expression of CR3. Both M-CSF and GM-CSF, but not human IL-3, induced the proliferation of Kupffer cells in a dose-dependent manner, and after 7 days, the number of the cells increased to about four to six times the initial number. The relatively high dose of GM-CSF downmodulated the M-CSF receptor on Kupffer cells and inhibited the cell proliferation induced by the optimal dose of M-CSF. These data indicated that murine Kupffer cells have a different phenotype from other macrophages and that they respond to M-CSF and GM-CSF, leading to functional maturation and proliferation.

Animals↗
PubMed1996

Aerosolization of imipenem/cilastatin prevents pseudomonas-induced acute lung injury.

Aerosolization of imipenem/cilastatin was compared with continuous intravenous infusions of the antibiotic for pharmacokinetic/pharmacodynamic analysis. The concentrations of imipenim/cilastatin in bronchoalveolar lavage fluids (BAL) obtained from rats exposed to the aerosolized antibiotic were significantly greater than the concentrations in BAL in the rats that had received intravenous infusions of imipenem/cilastatin. The two methods of antibiotic delivery were compared for their effects on bacterial-induced lung injury in rats that had Pseudomonas aeruginosa instilled into their airspaces. The aerosolization of antibiotic was associated with significantly decreased bacterial-induced lung injury. The high concentrations of antibiotic in the airspaces secondary to aerosolization appears to kill bacteria more quickly and preserve lung epithelial and endothelial integrity better than systemic delivery of the same antibiotic.

Administration, Inhalation↗
PubMed1996

A case of malignant transformation in thoracic vertebral hemangioma following repetitive irradiation and extraction.

We report a rare case of thoracic vertebral hemangioma which developed into angiosarcoma during the course of repetitive operations and irradiation. A 44 year old female was operated on for hemangioma of the first thoracic vertebra. The diagnosis of hemangioma was confirmed histopathologically with the specimen from the first operation. The tumor developed multiple lesions later in the clinical course after the first operation, these lesions were removed in four consecutive operations and each histological diagnosis was that of hemangioma. Throughout the period of these operations, the patient was treated with steroid, and with radiotherapy simultaneously. The patient underwent the fifth operation for the recurrence of the tumor on 26 March 1990, and the histopathological diagnosis was not hemangioma but hemangiosarcoma which was considered a malignant transformation. The tumor cells immunohistochemically revealed positive staining with UEA-I, Factor-VIII, as the tumor immunohistochemically showed a vascular endothelioid nature.

Adult↗
PubMed1996

Cervical intra-epithelial neoplasia (CIN) III of the uterine cervix in a young female associated with AIDS.

A case of cervical intraepithelial neoplasia (CIN) III implying severe dysplasia or carcinoma in situ of the uterine cervix in a 24 year old Japanese female patient with acquired immunodeficiency syndrome (AIDS) is reported. Autopsy revealed marked systemic atrophy of lymph nodes, Pneumocystis carinii pneumonia, pulmonary aspergillosis, acute pancreatitis and CIN III of the portio vaginalis uteri. The human papillomavirus (HPV) genome was detected in sections of the CIN III by polymerase chain reaction. This is the first autopsy report of cervical neoplasia in a patient with AIDS in Japan, and the pathogenesis of CIN III in this case was associated with HPV infection. Gynecological examination should be mandatory for female patients with human immunodeficiency virus infection.

AIDS-Related Opportunistic Infections↗
PubMed1996

Clear cell odontogenic carcinoma in the mandible: histochemical and immunohistochemical observations with a review of the literature.

A rare case of clear cell odontogenic carcinoma was investigated using histochemical and immunohistochemical methods. The tumor occurred in the anterior mandible of a 69-year-old Japanese man. Histologically, the tumor was composed mostly of large clear cells and squamous cells. Columnar-shaped cells with basophilic nuclei polarized away from the basement membrane were observed at the periphery of the tumor foci. The tumor cells had aggressively invaded muscle and perineural tissues. The tumor cells were positive for PAS staining. Immunohistochemically, tumor cells reacted positively to keratin, cytokeratin19, epithelial membrane antigen, and S-100 protein. The tumor was diagnosed as a clear cell odontogenic carcinoma. Its characteristics are discussed in term of its histopathological, histochemical and immunohistochemical features.

Aged↗
PubMed1996

[Bacteriological studies of travellar's diarrhoea. 5) Analysis of enteropathogenic bacteria at Osaka Airport Quarantine Station from January 1992 through September 3rd, 1994].

During the last 2 years and 8 months before the closure of Osaka Airport Quarantine Station (from Jan. 1992 to Sep. 3, 1994), a total of 7,421,909 overseas travellers were quarantined. 15,919 reported themselves of suffering from diarrhoea. Bacteriological examination of a total of 6,031 individuals' stools were performed. 1) Various enteropathogenic bacteria were isolated from 31.2% of the stools examined. Isolated species were as follows: Plesiomonas shigelloides, 1,127 cases (59.9%); Vibrio parahaemolyticus, 293 cases (15.6%); Salmonella spp., 262 cases (13.9%); Shigella spp., 235 cases (12.5%); Aeromonas sobria, 93 cases (4.9%); V. cholerae non-O1, 69 cases (3.7%). 2) The enteropathogenic bacteria were isolated through out the year without any seasonal variation. 3) The major regions where the travellers were infected with the pathogens are as follows: V. cholerae non-O1 (NAG Vibrio) and enteropathogenic Escherichia coli, South-East and South-West Asia; Vibrio other than NAG, South-East and East Asia; Shigella, widely distributed but especially in India; P. shigelloides and Salmonella, widely distributed. 4) 2 strains of toxigenic (cholera toxin-producing) V. cholerae O139 were isolated from patients who had visited Indonesia and Thailand, respectively. 5) In 320 cases (17%), plural enteropathogenic bacteria were isolated from single patients, suggesting a high frequency of the mixed infections. 6) Among Shigella strains, S. sonnei were isolated the most, followed by S. flexneri (24.7%), S. boydii (8.8%) and S. dysenteriae (2.9%). 7) Among Salmonella serovers, Salmonella Enteritidis was isolated the most frequently (39 cases, 14.1%). 8) 218 (91.6%) of 238 Shigella strains and 103 (37.6%) of 276 Salmonella strains were resistant to one or more drugs tested (SM.CP.TC.KM.ABPC.NA.OFLX). 9) All of the 22 V. cholerae O1 strains were Ogawa, E1 Tor. Among them, 19 were toxigenic strains and 3 were non-toxigenic. 10) O4:K8 was the most frequently isolated serover of V. paraemolyticus. 87.4% of all V. parahaemolyticus strains were positive with thermostable direct hemolysin (TDH) gene, and 12.6% of them were positive with TDH-related hemolysin (TRH) gene by DNA-probe methods.

Diarrhea↗
PubMed1996

Exotoxin A stimulates fluid reabsorption from distal airspaces of lung in anesthetized rats.

To determine whether exotoxin A may affect the transport of fluid across the lung epithelium, two isogenic strains of Pseudomonas aeruginosa PA103 (10(8) colony-forming units), one (PA103 tox omega) with a structural gene mutation in exotoxin A, were instilled into the distal airspaces of anesthetized rats. PA103 parental strain, but not its mutant, stimulated the removal of fluid from the distal airspaces of the lung. Instillation of exotoxin A alone caused a dose-dependent increase in the fluid transport across the lung epithelium. Instillation of amiloride (10(-3) M) with exotoxin A demonstrated that this effect partially depended on increased uptake of sodium across the lung epithelium. The absence of stimulation after instillation of an exotoxin A mutant (PE delta Glu553) without ADP-ribosyltransferase activity demonstrated that the effect of exotoxin A depended on its ADP-ribosyltransferase activity. Finally, the instillation of exotoxin A in rats depleted of macrophages indicated that the effect of exotoxin A was not secondary to the activation of alveolar macrophages by this toxin. In conclusion, these results indicate that the in vivo release of exotoxin A by live airspace P. aeruginosa directly stimulates the fluid removal from the airspaces by the lung epithelium. This may alter the volume or composition of airway secretions, and may contribute to the lung disease in patients infected with P. aeruginosa.

ADP Ribose Transferases↗
PubMed1996

Depletion of alveolar macrophages decreases neutrophil chemotaxis to Pseudomonas airspace infections.

The mechanism for neutrophil (PMN) influx into infected airspaces of the lung is not known. To determine whether alveolar macrophage products are important in the initiation of chemotaxis, we depleted rats of alveolar macrophages by aerosolizing negatively charged oligolamellar liposomes complexed to clodronate disodium. Ninety-five percent of the alveolar macrophages were depleted, and lung injury and inflammation were minimized with this depletion technique. Rats depleted of alveolar macrophages were then anesthetized, and either 5 x 10(6) colony-forming units (CFU) or 5 x 10(7) CFU of Pseudomonas aeruginosa were instilled into the airspaces of these animals. When recombinant macrophage inflammatory protein MIP-2 was intratracheally instilled into rats depleted of alveolar macrophages, PMN were recruited to their airspaces. Nonetheless, PMN numbers were decreased in the lavage fluids when moderate or large inoculums of bacteria were instilled into depleted rats, although the PMN response appeared dose dependent. Levels of bioactive tumor necrosis factor-alpha and immunoreactive proteins CINC/gro (cytokine-induced PMN chemoattractant) in the lavage fluids obtained from infected rats depleted of alveolar macrophages were significantly decreased compared with the levels in the lavage fluids obtained from normal infected rats. MIP-2 mRNA expression, as detected by Northern analysis, was also decreased in the infected lungs of depleted rats, and the lavage fluid from these rats had significantly decreased chemotactic activity. Therefore these results suggest that alveolar macrophage products play a direct role in the initial recruitment of PMN into infected lungs.

Animals↗
PubMed1996

Melatonin rhythm is not shifted by lights that suppress nocturnal melatonin in humans under entrainment.

Effects of a single light exposure on the circadian rhythm in plasma melatonin were, examined in young males to obtain the threshold of light intensity for suppressing the nocturnal melatonin level on the one hand and to understand the relationship between the light-induced phase shift of melatonin rhythm and the melatonin suppression on the other hand. Eight subjects spent 3 days in an experimental living facility where light intensity was set below 200 lx and were exposed to light for 3 h in the early morning on the 2nd day. The same procedure was repeated five times in each subject with an interval of at least 3 wk, and one of five light intensities was tested in each trial. As a result, nocturnal melatonin level was not suppressed by light of 200 lx but significantly suppressed by light of intensity > or + 500 lx. On the other hand, the circadian melatonin rhythm was not shifted by any light intensity up to 10,000 lx. It is concluded that the threshold of light intensity for suppressing the melatonin level is located between 200 and 500 lx in young Japanese males, and the threshold for phase shifting the circadian melatonin rhythm was much greater than that for suppressing the nocturnal melatonin level in humans under entrained conditions.

Adult↗