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S Asai

Publications and source records attributed to S Asai.

At least 127 records · Page 7Linked to original sources
PubMed1994

[Thymic cyst].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed1994

[An autopsy case of urinary bladder carcinoma with pulmonary infarction and subacute cor pulmonale caused by tumor embolization].

Pulmonary tumor embolism is a common finding at autopsy but is difficult to diagnose clinically antemortem. We report an autopsy case of urinary bladder carcinoma associated with tumor emboli of the pulmonary arteries and subsequent pulmonary infarctions. An eighty-six-year-old man with bloody sputum showed multiple infiltrates on chest X-ray and multiple pleural based parenchymal lesions with truncated apex on computed tomography. The patient had a history of radiation therapy against urinary bladder carcinoma two years earlier. Transitional type carcinoma cells were identified from a urine sample obtained on admission. Three weeks later, the patient developed subacute cor pulmonale and died in severe respiratory distress. Postmortem examination revealed primary carcinoma of the urinary bladder. Multiple tumor emboli of pulmonary arteries and subsequent pulmonary infarctions were visible microscopically. There was a large amount of effusion in both the pleural and the abdominal space. The heart contained focal scarring and mild right ventricular hypertrophy and there was congestion of the lungs, liver, kidneys and spleen. Pulmonary tumor embolization may present at any stage of the patient's illness but rarely causes subsequent pulmonary infarctions. Cytologic examination of blood samples obtained from Swan-Ganz catheters may be useful in the diagnosis of tumor embolization.

Aged↗
PubMed1993

Insulin stimulates association of insulin receptor substrate-1 with the protein abundant Src homology/growth factor receptor-bound protein 2.

Insulin activates the ras proto-oncogene product p21ras (Ras) by stimulating conversion of the inactive GDP-bound form of Ras to the active GTP-bound form. The protein ASH (for abundant Src homology) (Matuoka, K., Shibata, M., Yamakawa, A., and Takenawa, T. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 9015-9019) is composed of one Src homology (SH)2 and two SH3 domains and highly homologous to the Caenorhabditis elegans protein sem-5 that couples a tyrosine kinase to a Ras protein. We have studied an interaction of ASH with insulin-stimulated tyrosine-phosphorylated proteins in Chinese hamster ovary cells overexpressing human insulin receptors (CHO-HIR cells). In an anti-ASH (alpha ASH) immunoprecipitates, we detected a 170-kDa phosphoprotein that was recognized by an anti-phosphotyrosine antibody and an anti-insulin receptor substrate 1 antibody (alpha IRS-1) from the insulin-stimulated [32P]orthophosphate-labeled CHO-HIR cells. We failed to detect the tyrosine phosphorylation of the protein ASH. These data suggested that insulin stimulates IRS-1.ASH complex formation in intact cells. Incubation of an ASH fusion protein with the lysates of insulin-stimulated CHO-HIR cells revealed that the fusion protein of ASH was able to bind the tyrosine-phosphorylated 170-kDa protein that was recognized by alpha IRS-1. We also demonstrated that fusion protein of ASH was able to bind the fusion protein of tyrosine-phosphorylated IRS-1 fragments, suggesting that ASH is able to bind tyrosine-phosphorylated IRS-1 directly. These data suggest that IRS-1.ASH complex formation may play a role in coupling the insulin receptor kinase to a Ras signaling pathway. Furthermore, we observed an insulin-stimulated phosphatidylinositol (PI) 3-kinase activity in alpha ASH immunoprecipitates, suggesting the formation of an ASH.IRS-1.PI 3-kinase complex. This complex formation was detected as early as 10 s after insulin stimulation in intact CHO-HIR cells. This is the first report that supports the notion that IRS-1 binds several signal transducing molecules containing SH2 domains, thus serves as an SH2 docking protein that transduces insulin's signal multidirectionally.

Adaptor Proteins, Signal Transducing↗
PubMed1993

Comparative study of the cellular fatty acids of methicillin-resistant and -susceptible Staphylococcus aureus.

The cellular fatty acid compositions of 26 strains of methicillin-resistant Staphylococcus aureus (MRSA) and 17 strains of methicillin-susceptible S. aureus (MSSA) were analyzed by gas-liquid chromatography. The fatty acid compositions of the two groups were very similar with 16 identified components. The major fatty acids were Ci14 = 0, Ci15 = 0, C18 = 0 and C20 = 0. Among these fatty acids, the percentage of the Ci15 = 0 fatty acid component of MRSA strains (11.4 +/- 3.9%) was statistically higher than that of MSSA strains (6.2 +/- 2.4%) (p < 0.001). On the other hand, the percentage of the C20 = 0 fatty acid components of MRSA strains (20.2 +/- 8.8%) was statistically lower than that of MSSA strains (30.7 +/- 10.4%) (p < 0.001). The production of beta-lactamase and beta-hemolysin in both groups' strain was also unrelated to the relative amounts of the fatty acid components. These results indicated a statistical tendency for the percentage fatty acid compositions of the MRSA strains to be quantitatively different from those of the MSSA for both the Ci15 = 0 and C20 = 0 fatty acid components. Analysis of the fatty acid compositions may have an application in the differentiation of MRSA and MSSA strains.

Anti-Bacterial Agents↗
PubMed1993

[A case of pulmonary asbestosis with slightly increased serum IgE concentration and histopathological changes resembling DIP].

A 68-year-old male presented with cough and sputum. He had suffered from these symptoms for ten years prior to admission. Chest roentgenogram revealed reticulonodular shadows in the lower fields of both lungs. CT scan of the chest revealed an interstitial pattern in the lower field of both lungs. Honeycombing and bullous pattern were also present in the subpleural area. The patient had a history of dust and asbestos inhalation while working as an electrician. Eosinophilia of the peripheral blood and BALF, and a slightly increased serum IgE concentration were noted. Open lung biopsy revealed interstitial fibrosis with intra-alveolar macrophage accumulation and asbestos bodies. The histopathological features resembled UIP and DIP, although DIP is uncommon in pulmonary asbestosis. The slightly increased serum IgE concentration was considered to be an additional effect of asbestos. This is a case of pulmonary asbestosis with intriguing immunological and histopathological features.

Aged↗
PubMed1992

The inhibition of lymphocyte blastogenesis by asparaginase: critical role of glutamine in both T and B lymphocyte transformation.

L-Asparaginase has long been used in the treatment of acute lymphoblastic leukemia or malignant lymphoma in childhood. To determine cell type specific sensitivity to this drug, the L-asparaginase-mediated inhibition of blastogenesis of human peripheral T or B lymphocytes was compared. The rate of incorporation of [3H]-thymidine into the DNA of either T lymphocytes due to phytohemagglutinin (PHA) or B lymphocytes due to Staphylococcus aureus Cowan I (SAC) was measured by the addition of Escherichia coli L-asparaginase in the medium. The blastogenic response of either T or B lymphocytes was also determined in medium depleted of exogenous asparagine and/or glutamine, both of which are hydrolyzed by this enzyme. The in vitro blastogenesis of either human T lymphocytes due to PHA or B lymphocytes due to SAC was inhibited by the inclusion of asparaginase in the medium. The deprivation of exogenous asparagine did not have any inhibitory effect on the blastogenic response of both T and B lymphocytes to each mitogen. On the other hand, the glutamine concentration in the culture medium provided a critical influence on the proliferative response of T and B lymphocytes. The rate of incorporation of [3H]-thymidine into DNA was increased markedly as the concentration of glutamine was increased from 2(-7)-2 mmol/l. It is concluded that the mechanism of inhibition of PHA- or SAC-stimulated lymphocyte blastogenesis by L-asparaginase is not asparagine deprivation but glutamine deprivation. Glutamine, which is the most abundant amino acid, is thought to have an important role in the immune response of lymphocytes.

Asparaginase↗
PubMed1992

[A case of mediastinitis and bilateral pyothorax, following acute epiglottitis with concurrent Aspergillus infection].

Life threatening mediastinitis as a complication of acute epiglottitis is very rare. A 38-year-old male in previously good health was admitted to our hospital in a state of unconsciousness. Seven days prior to admission he had complained of a sore throat, dysphagia, high fever and dyspnea. A chest X-ray on admission showed widening of the mediastinum, mediastinal emphysema, subcutaneous emphysema and left pleural effusion. Bronchoscopy showed the swelling of supraglottic structures. He was diagnosed as having acute mediastinitis and pyothorax as a complication of acute epiglottitis, but pathogens were not identified. The blood was hyperglycemic and insulin therapy was started. Though he gradually improved by massive antibiotic therapy, steroid therapy, tracheotomy and surgical drainage of both the left thoracic cavity and the mediastinum, he died suddenly of massive hemoptysis. Autopsy revealed that the acute mediastinitis had healed, but that the Aspergillus infection was present in both lungs and the pericardium. The Aspergillus infection was not lethal in the present case, and it seemed that death had resulted from arterial hemorrhage caused by erosion of the trachea. The present case suggests the need for antifungal therapy even in non-immunocompromised patients in particular when massive doses of antibiotics and steroids are administered.

Acute Disease↗
PubMed1992

[The inhibitory effects of anti-asthmatic agents on ethanol-induced bronchoconstriction in Japanese asthmatic patients].

Asthmatic symptoms are worsened after drinking small amounts of alcoholic beverages in Japanese asthmatic patients. Our previous results showed that the ingestion of pure ethanol caused a fall in FEV1.0 in about half of the Japanese asthmatics we studied. We studied the inhibitory effects of pretreatment with three kinds of anti-asthmatic agents on ethanol-induced bronchoconstriction in six Japanese asthmatic patients. We tested oral cyproheptadine hydrochloride (8 mg), which is an anti histamine agent, inhaled disodium cromoglycate (2 mg), which has an inhibitory effect on the release of chemical mediators from mast cells, and inhaled atropine sulfate (3 mg), which is an anti-cholinergic agent. Pretreatment with cyproheptadine significantly inhibited the fall in FEV1.0 120 minutes after ethanol challenge (p less than 0.05). Inhaled DSCG had significant inhibitory effects on the fall in FEV1.0 15 and 30 minutes after ethanol challenge (p less than 0.05). Inhaled atropine had no inhibitory effect. These results suggest that histamine, released from mast cells, plays an important role in ethanol induced bronchoconstriction in Japanese asthmatic patients.

Adult↗
PubMed1992

[A case of interstitial pneumonitis with hemoptysis, BOOP (bronchiolitis obliterans organizing pneumonia) pattern, granulomas and foreign body giant cells in lung biopsy].

A 66-year-old male presented to our hospital in January 1990 with chief complaints of hemoptysis and cough. These symptoms had developed 10 months previously and had gradually increased. Fine crepitations were audible over the right lower lung field. There were no results suggesting an inflammatory process such as leucocytosis, elevation of ESR or positive CRP reaction. Chest X-ray film on the first visit showed fine nodular shadows in the right lower lung field, and chest CT revealed fine nodular shadows and mild dilatation of the right lower lobe bronchus. Transbronchial lung biopsy specimens showed granulomas with multinucleated giant cells, alveolitis and Masson bodies. The open lung biopsy specimens showed numerous macrophages and foreign body giant cells, and extensive organizing exudates in the bronchioles and alveolar spaces. Proliferation of smooth muscle and fibrosis around the dilated bronchioles were also seen. Thus, this patient demonstrated BOOP pattern, with granulomas and foreign body giant cells. His hemoptysis appeared to have resulted from inflammation of dilated bronchioles. His symptoms and abnormal shadows on chest X-ray improved without any therapy after admission. After treatment with corticosteroid, the diffuse fine nodular shadows disappeared. There has been no recurrence of symptoms to date, although this patient has continued living in the same environment as prior to admission. BAL findings during his prolonged follow-up revealed decrease in lymphocytes and elevation of CD4/CD8 ratio. Although the presence of granulomas suggests the possibility of an allergic reaction, no antigenic material could be identified in this case.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Clinical and pathological investigation of opportunistic pulmonary mycoses in autopsy cases].

Clinical and pathological investigations were performed in 58 cases of opportunistic pulmonary mycoses diagnosed at autopsy during the 10 years between 1979 and 1988 at Sasebo General City Hospital. The following findings were obtained. 1) The incidence of opportunistic pulmonary mycoses during the 10 years was 7.7%, with a significant increase in the incidence of fungal infections during the last 5 years of the study. The incidence of pulmonary mycoses was higher in patients with blood dyscrasia than in those with solid tumor or benign disease (p less than 0.001). 2) Administration of steroid hormone and anticancer drugs were suspected to be causative factors in the development of pulmonary aspergillosis and cryptococcosis, but not in candidiasis. 3) Characteristic radiographic patterns and clinical symptoms were absent in cases of pulmonary candidiasis due to the small size of the lesions and the high incidence of other complicating pulmonary infections and edema. 4) The most common initial roentgenographic pattern in opportunistic pulmonary aspergillosis was localized infiltrate, subsequently progressing to either multifocal infiltrates or cavitation. 5) The initial symptom in opportunistic pulmonary aspergillosis was usually high fever, and the radiographic abnormalities appeared later. The median duration between onset and death in 19 patients with pulmonary aspergillosis was 23.1 days. 6) Pulmonary aspergillosis should be suspected in the compromised host with high fever refractory to antibiotics and pulmonary infiltrates. Empiric antifungal therapy should be initiated at an early stage for the best chance for survival.

Aged↗
PubMed1991

Quantitative analysis of the Epstein-Barr virus-inducing properties of short-chain fatty acids present in the culture fluids of oral bacteria.

The culture fluids of various anaerobic bacteria induced the synthesis of early antigens (EA) in Epstein-Barr virus (EBV) carrying lymphoblastoid cells. The culture fluids of Corynebacterium butyricum and Fusobacterium nucleatum were the effective inducer on EA. The inducing activity was, to some extent, dependent on their n-butyric acid content, but appeared to be regulated by yet unidentified materials.

Antigens, Viral↗
PubMed1991

Effect of 9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta-(b)-quinoline monohydrate hydrochloride (NIK-247) on cholinergic enzyme activity in rats.

An in vitro comparison demonstrated that the concentration of NIK-247 that inhibited cholinesterase (ChE) activities to half the normal level (ID50) was 1.3 x 10(-6) M. This value was higher than those for both physostigmine (PHY; 1.2 x 10(-7) M) and tetrahydroaminoacridine (THA; 3.6 x 10(-7) M), which are used as cholinesterase inhibitors in the treatment of cholinergic deficits. Neither NIK-247 nor THA affected the activity of choline acetyltransferase (ChAT). These inhibitions of ChE by NIK-247 and PHY lasted for 2 h, while that by THA lasted for over 4 h. In the effects of NIK-247 and PHY, the concentrations of intrastriatal acetylcholine (ACh) were changed in relation to the inhibition of the ChE activity. However, THA caused a transient increase in the ACh level lasting for only 2 h instead of inhibiting the enzyme activity for over 4 h. These findings suggest that NIK-247 is a drug with a similar profile in its effect on cholinergic neurons to PHY, the prototype drug among ChE inhibitors. The data indicate that NIK-247 may be useful as a drug for the treatment of central as well as peripheral deficits of the cholinergic mechanism.

Acetylcholine↗
PubMed1991

[A case of severe near-drowning: the speech ability was regained on the 65th hospital day].

A 3 y.o. boy suffered cardiac arrest after submersion in a winter pond for more than fifteen minutes. He was transferred to our hospital and was successfully resuscitated. Although his neurological condition was severely damaged at the beginning, he started searching objects with his eyes on the 18th hospital day, speaking on the 65th hospital day and walking by himself on the 76th hospital day. His consciousness fully recovered eventually. The treatments consisted of "HYPER" as suggested by Conn AW, et al. and active anti-hypertensive therapy. These treatments and the cold temperature of winter time might have contributed to the good neurological recovery of the patient.

Child, Preschool↗