Biomedical subjects

Y Kawabata

Publications and source records attributed to Y Kawabata.

At least 109 records · Page 6Linked to original sources

PubMed1997

Talc and amosite/crocidolite preferentially deposited in the lungs of nonoccupational female lung cancer cases in urban areas of Japan.

To analyze the correlation between asbestos lung burden and lung cancer, lungs of 211 female cases with and without lung cancer were examined. Phase-contrast microscopic (PCM) counting of ferruginous (FBs) and uncoated fibers (UFs), which had length longer than 5 microns and aspect ratios greater than 3:1, revealed a significantly higher level of FBs plus UFs in urban lung cancer cases than urban non-lung cancer cases (1380.5 vs. 550.3; p < 0.001). No difference was noted between rural lung cancer and non-lung cancer cases. Analytical electron microscopic studies identified various kinds of mineral fibers with an aspect ratio greater than 3:1 in the lung tissue including chrysotile, actinolite/tremolite, amosite/crocidolite, fibrous talc, mica, silica, iron, wollastonite, chlorite, kaoline, and others. The most frequently detected fibers were thin, short chrysotile fibers, most of which could not be found by PCM, followed by relatively thick, long actinolite/tremolite fibers, fibrous talc, and in a smaller number, amosite/crocidolite of intermediate length and width. Amosite/crocidolite and fibrous talc counts in urban lung cancer cases were greater than those of urban non-lung cancer cases, rural lung cancer, and rural non-lung cancer cases; these findings were consistent with PCM analysis. Therefore, it is suggested that fibers detected in PCM observation may be mainly amosite/crocidolite with some parts fibrous talc and that fibrous talc in urban environments may be another candidate for carcinogenic or cocarcinogenic factors of female lung cancer.

Adult↗

PubMed1997

Serum N-acetyl-beta-D-glucosaminidase activity in a genetic rat model of non-insulin-dependent diabetes mellitus.

Serum N-acetyl-beta-D-glucosaminidase activity (NAG) is a possible predictor of vascular injury in hypertension. We assessed whether the activity of this enzyme reflects vascular damage in a genetic rat model of non-insulin-dependent diabetes mellitus (NIDDM) in humans. Otsuka Long-Evans Tokushima Fatty (OLETF) rats fed a regular chow were treated with the angiotensin converting enzyme (ACE) inhibitor imidapril for 16 wk. Systolic blood pressure increased in a time-dependent manner in the untreated OLETF rats as compared with that in the control Long-Evans Tokushima (LET) rats. The blood pressure elevation was associated with increases in cardiac and aortic weight. Imidapril treatment significantly attenuated the blood pressure elevation and reduced the increases in cardiac and aortic weight. The untreated OLETF rats had higher plasma glucose and insulin concentrations than did the LET rats and presented with glucosuria at the age of 22 wk. Imidapril treatment strikingly decreased plasma glucose levels and the glucosuria. Plasma insulin concentrations decreased, approaching those of the non-diabetic control LET rats. ACE inhibitor treatment attenuated the nodular lesions in the glomeruli of OLETF rats and improved the kidney function. Serum NAG activity increased significantly by 35% in the untreated rats; this increase was attenuated significantly by imidapril treatment. The reduction in serum NAG activity correlated with improvement in cardiovascular injury. In contrast, there were no changes in urinary NAG excretion in the three OLETF rat groups. In addition, NAG excretion did not correlate with indices of cardiovascular injury. These data suggest that serum NAG activity is useful in predicting injury in the cardiovascular system in rats with diabetes mellitus.

Acetylglucosaminidase↗

PubMed1997

Immunosuppressant HR-325 attenuates progression of malignant arteritis in the kidney of Dahl salt-sensitive rats.

We investigated the effects of the immunosuppressant HR-325 on arterial lesions in Dahl rats with salt-induced hypertension. Forty-eight 6-wk-old Dahl salt-sensitive (DS) rats were divided into 1) a low-salt (0.3% NaCl) group, 2) a high-salt (4% NaCl) group, 3) a high-salt and low-dose (1 mg/kg) HR-325 group, and 4) a high-salt and high-dose (30 mg/kg) HR-325 group. The rats were treated for 8 wk. Various variables of renal function and morphological alterations in the kidney were assessed. Blood pressure was measured by the tail-cuff method. HR-325 significantly decreased systolic blood pressure in a dose-dependent manner throughout the study. HR-325 tended to decrease plasma creatinine level and increase creatinine clearance rate. Morphological studies revealed that HR-325 treatment strikingly resolved infiltration of immune-related cells in perivascular and intraluminal lesions, thereby decreasing the total arterial injury score by 32%. High-dose HR-325 also attenuated glomerulosclerosis and tubular injury by 35% and 34%, respectively, as compared with untreated high-salt Dahl S rats. Reduced levels of immune-related cells resulted in a decrease in urinary nitrite excretion. These data indicate that long-term treatment with the immunosuppressant HR-325 decreases systolic blood pressure in Dahl salt-sensitive rats, and that this decrease is associated particularly with resolution of infiltration of immune-related cells in arterial lesions. Hyperimmune state is responsible in part for the susceptibility of Dahl S rats to hypertensive organ damage.

Aniline Compounds↗

PubMed1997

Lipid metabolism and renal protection by chronic cicletanine treatment in Dahl salt-sensitive rats with salt-induced hypertension.

We investigated the role of lipid metabolism in renal protection by chronic cicletanine treatment in Dahl salt-sensitive (Dahl S) rats with salt-induced hypertension. Forty-four 6-week old Dahl S rats were divided into four groups: (1) low-salt (0.3% NaCl) control group: (2) high-salt (4% NaCl) control group; (3) low-dose (10 mg/kg/day) cicletanine (CICL)-treated group given a high-salt diet; and (4) high-dose (30 mg/kg/day) cicletanine-treated group given a high-salt diet. The rats were treated for 6 weeks; blood pressure was measured by the tail-cuff method. Cicletanine significantly reduced the systolic blood pressure in a dose-dependent manner (223 mmHg in the high-salt controls vs 195 mmHg in the high-dose, high-salt group, p < 0.01). Cicletanine treatment did not affect plasma concentration of total cholesterol or triglyceride or free fatty acid; in contrast, it significantly decreased low-density lipoprotein (LDL) cholesterol and increased high-density lipoprotein (HDL) cholesterol. Morphological examination demonstrated that glomerulosclerosis in the kidney was significantly improved by 15% with high-dose cicletanine (p < 0.01). Multivariate analysis revealed that glomerular sclerosis was determined independently by LDL cholesterol levels and arterial injury score, but not by total cholesterol or HDL cholesterol levels or blood pressures. LDL cholesterol was also an independent predictor of urinary excretion of protein. Thus, it is suggested that cicletanine treatment lowers the levels of LDL cholesterol in Dahl salt-sensitive rats, and that besides blood pressure reduction, this decrease in LDL cholesterol level contributes, in part, to regression of glomerular injury in salt-induced hypertension.

Animals↗

PubMed1997

[Randomized prospective trial of gentian violet with dibutyryl cAMP and povidone-iodine with sugar as treatment for pressure sores infected with methicillin-resistant Staphylococcus aureus in elderly patients].

A randomized prospective study was done to evaluate the two treatments for pressure sores infected with methicillin-resistant Staphylococcus aureus in elderly patients: Gentian violet plus dibutyryl cAMP (GVcAMP, n = 8) and povidone-iodine plus sugar (IS, n = 11). Age, underlying diseases, and nutritional status did not differ between the two groups. Specimens were obtained biweekly from the pressure sores and were cultured. The percentage of culture dishes with no methicillin-resistant S. aureus was 93% for the patients given GVcAMP, but only 74% for those given IS (p < 0.01). By the 14th week after the start of treatment, the mean area of the pressure sores in the GVcAMP group had decreased to 45% of the area at the start of treatment. In the IS group, the decrease was smaller to 56% of the area before treatment. No local or systemic adverse effects occurred in either group. GVcAMP is useful to treat pressure sores infected with methicillin-resistant S. aureus.

Aged↗

PubMed1997

[Unilateral mixed-dust pneumoconiosis with aluminum deposition associated with interstitial pneumonia].

A 63-year-old stoneworker complained of fever and a productive cough. His chest roentgenogram showed a nodular mass and a diffuse interstitial shadow in the right lung. Angiography of the pulmonary artery revealed obstruction of the right upper trunk. Open-lung biopsy was done. Histologic examination showed mixed-dust pneumoconiosis with a massive focus of mixed-dust fibrosis with silicotic nodules, and diffuse interstitial fibrosis of pattern with lymphoid infiltration. Chemical analysis revealed a high content of aluminum in lymph node, which was thought to be due to inhalation of alumina used for lettering stones. The unilateral interstitial pneumonia was thought to have developed due to deposition of free silica and aluminum dust. Although this patient had been given a diagnosis of rheumatoid arthritis and the value of rheumatoid factor was high, the interstitial pneumonia was not believed to be associated with the collagen vascular disease.

Aluminum↗

PubMed1997

Long-term infusion of kallikrein attenuates renal injury in Dahl salt-sensitive rats.

We investigated whether long-term infusion of kallikrein would attenuate renal injury in salt-induced hypertension in Dahl salt-sensitive (Dahl S) rats. A subdepressor dose of purified rat urinary kallikrein (RUK) (700 ng/day) was infused intravenously by an osmotic minipump for 4 weeks in male Dahl S rats fed a high-salt (2% NaCl) diet. This dose did not affect the time-dependent elevation of blood pressure. However, urinary protein excretion was significantly decreased, and the glomerular filtration rate was increased. These beneficial effects were reflected morphologically by an attenuation of the glomerulosclerotic lesions and tubular injury seen in the hypertensive Dahl S rats. The kallikrein infusion increased the urinary excretion of bradykinin and stimulated the excretion of cyclic GMP, suggesting that the kallikrein-kinin-prostaglandin and nitric oxide axes were enhanced by the RUK infusion. The alterations induced by such infusion were potentiated by the concomitant administration of the angiotensin converting enzyme inhibitor alacepril. These studies indicated that long-term replacement with rat tissue kallikrein attenuates renal injury in hypertensive Dahl S rats, and this is probably mediated by an enhanced function of the kallikrein-kinin-prostaglandin and nitric oxide systems.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1997

The implication of renin-angiotensin system on renal injury seen in Dahl salt-sensitive rats.

Angiotensin II (Ang II) progresses to remodeling of the cardiovascular system through nonhemodynamic as well as hemodynamic effects. There have been few data in vivo on whether subpressor concentration of Ang II is exerted to injure directly the cardiovascular system in hypertension. To test this hypothesis, we investigated, using Dahl salt-sensitive (Dahl S) rats, whether subpressor dose of Ang II progresses to cardiovascular injury observed in salt-induced hypertension. Recent studies have provided evidence that renin-angiotensin inhibition protects against renovascular injury in human hypertension as well as in experimental animals. Particularly in the case of Dahl salt-sensitive rats, a genetic model of volume-dependent hypertension in humans, they are likely to develop more severe arterial and renal injuries than those seen in spontaneously hypertensive rats with similar blood pressure levels. The mechanism of the susceptibility to hypertensive injuries is uncertain; however, renin-angiotensin inhibition significantly improved morphologic and functional injuries in the kidney of Dahl S rats. Conversely, subpressor dose of Ang II infusion exacerbated renal function and progressed to glomerulosclerotic lesions. Alterations of Ang II concentration in physiologic range influenced morphologic and functional injuries in Dahl S rats. Multivariate analysis revealed that activity of the renin-angiotensin system is an independent risk factor to glomerular injury in salt-induced hypertension. These data are in favor of the therapeutic strategy in human hypertension that inhibition of renin-angiotensin system is of value to produce beneficial effects of blood pressure reduction on organ injuries.

Animals↗

PubMed1997

[Autologous peripheral blood stem cell transplantation for CHOP-resistant mediastinal diffuse large B-cell lymphoma].

We report two cases of CHOP-resistant mediastinal diffuse large B-cell lymphoma (MDLCL) treated by autologous peripheral blood stem cell transplantation (auto-PBSCT). The patients were 17 and 28 year old female, and they had anterior mediastinal bulky masses at presentation. The clinical stage was IV in both patients. They were initially treated with 6 courses of bi-weekly CHOP therapy following by irradiation of the mediastinal tumors. During the last few cycles of CHOP therapy, their disease had become progressive. They underwent auto-PBSCT after high-dose chemotherapy consisting of busulfan, cyclophosphamide and etoposide, but failed to achieve remission. They died within one year after the auto-PBSCT because of the disease progression. Our experience suggests that this conditioning regimen is not effective for CHOP-resistant MDLCL, and it is necessary to develop new conditioning regimens.

Adolescent↗

PubMed1997

[Necrotizing sarcoid granulomatosis diagnosed by video thoracoscopic lung biopsy].

A 28-year-old woman was admitted to our hospital because of chest pain. A chest roentgenogram and a chest computed tomogram revealed many nodular shadows on both sides. Examinations of specimens obtained by and by transbronchial lung biopsy during fiberoptic bronchoscopy were not diagnostic, and therefore video thoracoscopic lung biopsy was done. The lung lesion was characterized by aggregates of epithelioid cell granulomas, along with granulomatous and necrotizing angitis. We therefore diagnosed necrotizing sarcoid granulomatosis, and began to administer prednisolone. The nodular shadows disappeared within four weeks. In this case video thoracoscopic lung biopsy was useful in the diagnosis of necrotizing sarcoid granulomatosis in the lung.

Adult↗

PubMed1997

[Bufferin-induced lung injury manifesting as acute eosinophilic pneumonia].

A 26-year-old woman was admitted to our hospital because of dyspnea and fever one day after taking medicines for the common cold. A chest roentgenogram and a computed tomogram revealed diffuse patchy infiltrates in both lung fields. Examination of a specimen obtained by transbronchial lung biopsy showed thickening of alveolar walls and infiltration of eosinophils. Bronchoalveolar lavage fluid had many eosinophils. DLST was positive for Bufferin, which the patient took one day before the dyspnea and fever began. We believe that this patient's pulmonary disease was caused by Bufferin. We should realize that this widely used analgesic can cause acute eosinophilic lung disease. The patient was not given corticosteroids, and her condition improved soon after she stopped taking Bufferin.

Adult↗

PubMed1997

[A case of humidifier lung characterized by histopathologic feature].

A 61-year-old man was discharged from our hospital after recovering from bilateral fractures in the neck of each femur. However, a productive cough, dyspnea, and a high grade fever occurred eight hours after returning home. He was thus admitted once more. At rehospitalization, there was radiographic evidence of bilateral infiltrates and hypoxemia. Hypersensitivity pneumonitis was strongly suggested by radiographic evidence, by the fact that no new drugs had been administered, and by a positive result after an environmental provocation test. A diagnosis of humidifier lung was confirmed by a positive precipitins test for humidifier water. Several microorganisms were isolated from humidifier water, and precipitins tests for the isolated microorganisms were mostly positive. Microscopic examination revealed focal alveolitis, bronchiolitis, and perivasculitis. Perivascular leucocytic infiltrations around venules suggested that inhaled antigens might have also caused humidifier lung via a vascular route. Humidifier lung may be due in part to soluble factors, such as endotoxin, present in humidifier water.

Alveolitis, Extrinsic Allergic↗

PubMed1996

Mutations of the transforming growth factor beta type II receptor gene and microsatellite instability in gastric cancer.

Forty-three sporadic gastric cancers were analyzed with regard to whether mutations of simple repeated sequences in the transforming growth factor beta type II receptor (TbetaR-II) gene are associated with microsatellite instability (MSI) and gastric carcinogenesis. In 12 of the 43 cancers (28%), MSI was observed at least at 1 of the 2 microsatellite loci. Frameshift mutations of the TbetaR-II gene, all of which were 1 base deletion of 10 adenine repeats, were detected in 3 of 6 cancers, with MSI at 2 loci. However, mutations were not detected in 6 cancers, with MSI only at 1 locus and 31 cancers without MSI. Moreover, microanalysis in these cases revealed that the mutant-type alleles of TbetaR-II were invariably common in different areas within the tumor, in contrast to the markedly variable alleles of microsatellite loci. Our results suggest that frameshift mutation of the TbetaR-II gene may be a critical event associated with MSI and may contribute to carcinogenesis of the stomach. One of the possible mechanisms of escape from growth control by TGFbeta during gastric carcinogenesis could involve frameshift mutations of the TbetaR-II gene caused by DNA replication errors.

Adenine↗

PubMed1996

Intravenous catecholamines alter hepatic blood flow in conscious dogs with experimental hepatic denervation.

Hepatic blood flow is regulated by the autonomic nervous system; however, blood flow through the denervated liver has been controversial. The purpose of this study is to evaluate the changes in hepatic blood flow caused by experimental hepatic denervation during the intravenous infusions of catecholamines (dopamine or dobutamine) with or without prior administration of alpha-adrenoceptor antagonist (phenoxybenzamine) or beta-adrenoceptor antagonist (propranolol). The liver blood flow was measured using transit time ultrasonic flow meter probes at the portal vein and hepatic artery in conscious dogs which (a) underwent hepatic denervation (denervation group, n = 9) and (b) were intact (control group, n = 10). Norepinephrine concentrations in the liver were determined to evaluate the effects of hepatic denervation and were decreased at 1 week and 4 weeks after hepatic denervation. In the control group, dopamine and dobutamine produced an increase of portal venous blood flow (PVF). Conversely, hepatic denervation reduced the increase in PVF by dopamine and dobutamine. Dopamine with prior administration of phenoxybenzamine produced a much larger increase in PVF in both groups. Pretreatment of propranolol in both groups abolished the increasing effects of dopamine and dobutamine in PVF. Dopamine reduced the hepatic arterial blood flow (HAF) regardless of hepatic denervation. During dobutamine infusion, HAF was decreased by hepatic denervation and prior administration of propranolol. These results suggest that hepatic denervation reduces the increasing effects of catecholamines on the hepatic blood flow through greater enhancement of alpha-adrenergic effects than of beta-adrenergic effects in the hepatic vascular autonomic nerve response.

Animals↗

PubMed1996

Hereditary ceruloplasmin deficiency with hemosiderosis.

Hereditary ceruloplasmin deficiency with hemosiderosis (aceruloplasminemia) is a new disease characterized by systemic hemosiderosis, diabetes mellitus, neurological abnormalities and pigment degeneration of the retina. Loss of the ferroxidase activity of ceruloplasmin results in systemic iron deposition and tissue damage. Neuroimaging studies reveal iron deposition in basal ganglia and in the red and dentate nuclei. Cerebellar ataxia, extrapyramidal signs and dementia develop after middle age. We report a patient with undetectable serum ceruloplasmin levels and the above clinical manifestations. Sequence analysis of the cDNA of ceruloplasmin from this patient revealed an insertion of adenine in exon 3; this produced a premature stop codon.

Amino Acid Sequence↗

PubMed1996

The clinical features of Tourette's disorder with obsessive-compulsive symptoms.

Twenty-three patients with Tourette's disorder (13 with obsessive-compulsive symptoms [OCS] and 10 without) were comparatively investigated. In contrast to OCS-free Tourette's disorder patients, those with OCS were found to be characterized by (i) a higher incidence of volatile temper, (ii) a higher incidence of compulsive tics, (iii) a higher incidence of perinatal disorders and brain wave abnormalities, (iv) a higher severity as rated using the Severity Scale, and (v) a higher prevalence of complications, especially of developmental disorders. Of the subjects with OCS-accompanied Tourette's disorder, approximately half had developed OCS by the onset of tics. These findings suggest the likelihood that OCS-accompanied Tourette's disorder is more strongly associated with organic cerebral disorders, independently of sites of tic disorders, than is OCS-free Tourette's disorder.

Adolescent↗

PubMed1996

Structural characteristics of peptidoglycan fragments required to prime mice for induction of anaphylactoid reactions by lipopolysaccharides.

Structural characteristics of peptidoglycan fragments required to prime mice for the induction of anaphylactoid reactions by Salmonella abortusequi lipopolysaccharide were examined in endotoxin-resistant C3H/HeJ mice, with special focus on the disaccharide-pentapeptide [N-acetylglucosaminyl-beta(1-4)-N-acetylmuramyl-L-alanyl-D -isoglutaminyl-meso-2,6-diaminopimelyl (DAP)-D-alanyl-D -alanine] and its smaller partial derivatives. The bacterial and synthetic muramyl tripeptides (DAP- and lysine [Lys]-type, respectively) and synthetic muramyl dipeptide primed mice for induction of anaphylactoid reactions accompanied by death within 1 h. The disaccharide-tripeptide exhibited weaker activity, and the disaccharide-tetrapeptide and muramyl tetrapeptide exhibited marginal activity. In contrast, intact peptidoglycans of various bacteria and the disaccharide-pentapeptide lacked the priming activity, although they showed adjuvant activity similar to that of the above components.

Anaphylaxis↗

PubMed1996

Hachimi-jio-gan extract protects the kidney from hypertensive injury in Dahl salt-sensitive rat.

We investigated whether the Chinese herbal remedy, Hachimi-jio-gan extract, attenuates the renal injury seen in salt-induced hypertension in Dahl salt-sensitive (Dahl S) rats. Administration of this extract for 5 weeks dose-dependently decreased systolic blood pressure in Dahl S rats fed with a high-salt (2% NaCl) diet. This blood pressure reduction was associated with a decrease in cardiac mass and in thickness of the aortic wall. Urinary excretion of prostaglandin E2 was increased and glomerular filtration rate was improved with this treatment. Glomerulosclerosis and arterial injury in the kidney were morphologically improved. These data suggest that Hachimi-jio-gan extract exhibits an antihypertensive effect, which is associated with partial resolution of renal injury in salt-induced hypertension.

Animals↗