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Biomedical subjects

K Kuroda

Publications and source records attributed to K Kuroda.

At least 145 records · Page 8Linked to original sources
PubMed1997

Volatile organic compounds in urban rivers and their estuaries in Osaka, Japan.

The levels and distribution of 55 volatile organic compounds (VOCs) were determined by purge and trap GC-MS on water samples from 30 sites within the urban rivers and estuaries of Osaka, a populated industrialized city of Japan. Forty of 55 target VOCs listed in the US EPA Method 524.2 were detected. Dichloromethane (DCM) was found at higher levels at all of the sampling sites. The distribution of dominant VOCs followed four different patterns. First, the most common VOCs (DCM, toluene, trichloroethene and tetrachloroethene) showed concentration maxima in the river segments, and the sites of maximum concentration fluctuated due to irregular large spills and/or loadings. Second, one VOC (cis-1,2-dichloroethene) was evenly distributed in particular rivers due to fixed loadings. Both of these patterns were found in the upper and middle reaches. Third, some of VOCs (1,2,3-trichloropropane and benzene) were specific to a single industrial site and truceable to those sources. Finally, some VOCs showed no concentration maxima along the rivers and entered from multiple sources (chloroform and bromodichloromethane). Diurnal variations of VOCs at the border of the city area, receiving domestic and industrial discharges, provided information to interpret their observed downstream distribution and possible sources.

Journal Article↗
PubMed1997

Differential regulations of matrix metalloproteinases and tissue inhibitors of metalloproteinases in dermal fibroblasts by dibutyril cyclic AMP.

The influence of dibutyril cyclic AMP (dbcAMP) on the gene expression of matrix metalloproteinases (MMP)-1, MMP-2, MMP-3, tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2 was investigated in human skin fibroblasts by northern analyses. The treatment of dbcAMP increased MMP-1 and MMP-3 mRNA levels but decreased TIMP-1 mRNA levels in time and dose dependent manners. Procollagen alpha 1 (I), MMP-2 and TIMP-2 mRNA levels were unaltered by this reagent. Our data indicate that dbcAMP potentially enhances the degradation of extracellular components of connective tissue.

Bucladesine↗
PubMed1997

Azelastine suppresses the release of arachidonic acid metabolites from cultured human umbilical vein endothelial cells.

We investigated the effects of azelastine, an anti-allergic agent, on the release of arachidonic acid metabolites from cultured human umbilical vein endothelial cells (HUVEC). High performance liquid chromatography (HPLC) revealed that HUVEC treated with 10(-5) M azelastine released smaller amounts of arachidonic acid metabolites into the medium than control HUVEC. Azelastine significantly reduced the release of prostaglandin F2 alpha (PGF2 alpha), leukotriene B4 (LTB4) and 5-hydroxy-eicosatetraenoic acid (5-HETE) by HUVEC. These results suggest that azelastine may inhibit contraction of bronchial smooth muscle cells and reduce bronchial inflammation by suppressing the release of arachidonic acid metabolites from vascular endothelial cells.

Anti-Allergic Agents↗
PubMed1997

Possible carcinogenic potential of dimethylarsinic acid as assessed in rat in vivo models: a review.

The modifying effects of dimethylarsinic acid (DMA), the major metabolite of ingested arsenicals in most mammals, on chemical carcinogenesis were investigated using rat in vivo models and reviewed here. In a multi-organ bioassay, rats pretreated with 5 carcinogens were administered DMA at various concentrations in their drinking water. Significantly increased tumor induction due to DMA was observed in the urinary bladder, kidney, liver, and thyroid gland. This was associated with significantly elevated ornithine decarboxylase activity in the kidneys of DMA-treated animals. To estimate the hazard levels of its promoting influence, further examinations were carried out concerned with urinary bladder and liver carcinogenesis. Doses of 25 and 50 ppm, respectively, of DMA were found capable of enhancing lesion development in the two organs. In conclusion, our data indicate that DMA is a carcinogen or promoter in the urinary bladder, liver, kidney and thyroid gland, in line with previous epidemiological findings.

Animals↗
PubMed1997

Changes in cerebral blood flow accompanied with reduction of blood pressure treatment in patients with hypertensive intracerebral hemorrhages.

Blood pressure usually is reduced in patients with hypertensive intracerebral hemorrhage for the prevention of the expansion of the hematoma and recurrent hemorrhage in acute stage. However, disturbed autoregulation of cerebral circulation is expected, and decreased cerebral blood flow (CBF) caused by excessive hypotension has been pointed out. There are different mechanisms of action in hypotensives, thereby the influence of hypotension on CBF in patients with the thalamic hemorrhage was investigated using nitroglycerin (TNG), diltiazem hydrochloride (DH) and trimethaphan camsilate (TC). Average CBF in a hemisphere on the hematoma side, the hemisphere without hematoma, and around the hematoma showed a slight decline after administration of TNG or DH. However, CBF declined more, after TC than DH. DH and TNG are preferable in descending order to control blood pressure of patients with intracerebral hemorrhage in the acute stages in view of a smaller decline in CBF.

Adult↗
PubMed1997

Anticoagulant therapy during successful pregnancy and delivery in a Kawasaki disease patient with coronary aneurysm--a case report.

Thirty-one-year-old woman with Kawasaki disease wanted a child. She had a large coronary aneurysm on the left main coronary artery and complete obstruction of the right coronary artery, but there was no sign of ischemia. Heparin anticoagulant therapy was begun 8 weeks after the onset of pregnancy. The activated partial thromboplastin time (APTT) was successfully maintained at 1.5 to 2.0 times normal value during pregnancy and puerperium. There were no thromboembolic complications during pregnancy or after an uneventful cesarean delivery. The neonate was healthy.

Adult↗
PubMed1997

Trochlear and abducens nerve neurinomas accompanied by a cerebellopontine angle meningioma--case report.

A 66-year-old male presented with cerebellovestibular symptoms and hypesthesia of the V2 area of his face. Neuroimaging only detected a cerebellopontine angle (CPA) meningioma. The CPA meningioma was removed using the lateral suboccipital approach, which exposed small neurinomas arising from the trochlear and abducens nerves. Both neurinomas were removed intracapsularly. Postoperatively hypesthesia resolved, but other symptoms were unchanged. A karyotypic analysis of chromosome 22 and estrogen receptor analysis suggested absence of neurofibromatosis II, but the cause(s) of the genesis of the multiple diverse tumors was not determined. This extremely rare combination of neurinomas and meningioma was probably incidental, as there are no reports of any case which a combination of the trochlear and the abducens nerve neurinomas, much less one accompanied by a meningioma.

Abducens Nerve↗
PubMed1997

The characteristics of specific IgG to phthalic anhydride (PA)-albumin conjugate.

Phthalic anhydride (PA), used in the chemical industry, binds to proteins and causes allergic reactions. It is important to study the characteristics of antibody to PA-protein. We produced specific IgG against PA-rabbit serum albumin (RSA) by administering subcutaneous injections of PA-RSA conjugate to two rabbits. Both rabbits' sera had high titers of IgG not only to PA-RSA but also to PA-human serum albumin (HSA) and HSA. In enzyme-linked immunosorbent assay (ELISA) and ELISA HSA inhibition, specific IgG to PA-HSA revealed cross-reactivity to three other phthalyl anhydride conjugates, hexahydrophthalic anhydride (HHPA)-HSA, methylhexahydrophthalic anhydride (MHHPA)-HSA, and methyltetrahydrophthalic anhydride (MTHPA)-HSA, in both sera. Titers of IgG to HHPA-HSA, MHHPA-HSA, and MTHPA-HSA were not significantly different. On affinity chromatography, highly specific IgG to PA hapten alone was purified. In the serum not binding to PA column, specific IgG to PA-HSA was significantly less than in original serum, but levels of specific IgG to other phthalyl anhydride-HSA were unchanged. Rabbits immunized with PA-RSA produced at least two types of IgG: one is to PA hapten alone and the other may be against new antigenic determinants (NADs) on HSA.

Animals↗
PubMed1997

Detection of influenza virus RNA in peripheral blood mononuclear cells of influenza patients.

Gastroenteritis, arthralgaia and myalgia are frequently associated with influenza virus infections in humans. One explantation for these symptoms may be extrarespiratory transmission of virus by peripheral blood mononuclear cells (PBMC). We tried to detect genomic viral RNA of the nucleoprotein (NP) and H3 subtype hemagglutinin (HA) genes by the method of RT-PCR in PBMC of 18 children aged 1-14 who suffered from an influenza outbreak in the Kansai district of Japan between December 1992 and February 1993. Three of the 18 samples were RT-PCR positive. The NP gene sequence observed in one patient's PBMC was identical to that obtained from his throat swab fluid. The HA gene sequences observed in the two other PBMC differed from those of RT-PCR-amplified DNA from throat swabs by an order of 3-9 nucleotides. We believe these results suggest the presence of a PBMC-associated virus.

Adolescent↗
PubMed1997

[A case of systemic arterial supply to the normal left basal segments with no symptoms].

A 41-year-old man was admitted to Hirakata City Hospital because of an abnormal shadow on chest X-ray film. Chest X-ray film showed a tumorous shadow in the left anterior basal segment (S8). MRI showed aberrant arteries arose from the descending aorta clearly. Broncho-fibers-copy showed no defect of visible bronchi. Aortography showed one aberrant arteries arose from the descending thoracic aorta, circulated in the basal segment of the left lower lobe, and returned to the left pulmonary vein. Pulmonary arteriogram revealed defect of A8-10. Resection of left lower lobe was performed. In the resected specimen, the bronchi of the left lower lobe had a normal structure and showed a normal pattern of distribution.

Adult↗
PubMed1997

[Antigenic epitopes of influenza virus specific CTL].

CTLs play an essential role in the protection to influenza virus infection. Virus specific CTLs recognize the complex of class I molecule and epitope peptide derived from viral proteins on surfaces of virus infected cells. In these 10 years great progress has been made in understanding of the process of epitope peptide production and the structure of the peptide. It has been clearly shown that proteasome and TAP are involved in the class I restricted antigen processing and epitope peptides have motifs depending on class I allele. In this article topics concerning CTL epitopes of influenza viruses are described; especially prediction and identification of epitopes are mainly discussed.

Epitopes↗
PubMed1997

[Viremia in influenza: detection by polymerase chain reaction].

Gastroenteritis, arthralgia and myalgia are frequently associated with influenza virus infections in humans. One explanation for these symptoms may be that they are due to extra respiratory transmission of virus by viremia. We tried to detect genomic viral RNA of the nucleoprotein (NP) and H3 subtype hemagglutinin (HA) genes by method of RT-PCR in peripheral blood mononuclear cells (PBMC) of 18 children aged 1-14 who suffered from an influenza outbreak in the Kansai district of Japan between December 1992 and February 1993. Three of the 18 samples were RT-PCR positive. The NP gene sequence observed in one patient's PBMC was identical to that obtained from his throat swab fluid. The HA gene sequences observed in the two other PBMC differed from those of RT-PCR amplified DNA from throat swabs by an order of 3-9 nucleotides. Moreover we tried to isolate virus by co-culture with MDCK cells and RBC or WBC of the patients from an influenza outbreak between December 1993 and March 1994. No virus was isolated from 9 patients suffering from H3 subtype but virus was isolated from 5 of 17 patients suffering from type B influenza virus. We believe these results suggest that the viremia on influenza infection is not so rare.

Adolescent↗
PubMed1997

[Home infusion therapy for cancer patients at a near-terminal stage--analysis of cases who died at home].

To improve the quality of life in cancer patients at a near-terminal stage, we assisted patients to stay home using a system for home infusion therapy (HIT) established at Osaka Prefectural Habikino Hospital in 1994. From April in 1995 to April in 1996, 25 patients were treated at home using the HIT system for longer than 7 days. Thirteen out of 25 patients still stayed at home even at a terminal stage and died in their residences. There was no difference either in the mean age or in the HIT duration between 13 patients who died at home and the remaining 12 patients who were readmitted to their hospitals before death. However, 47% of the patients who died at home had been told their diagnoses by doctors and realized their own prognoses, while only 17% of the patients who died in the hospital knew their diagnoses and prognoses. Seventy-seven percent of the patients who died at home were given home oxygen therapy (HOT), against 33% of the patients who died in the hospital. Furthermore, the patients who died at home were given more intensive care than the patients who died in the hospital, because the former had a larger family than the latter. In conclusion, HIT at a near-terminal stage and death at home may be more readily accepted by patients who know their diagnoses and prognoses and have a large family.

Adult↗
PubMed1996

Differential activation of human platelets induced by Fc gamma receptor II cross-linking and by anti-CD9 monoclonal antibody.

Platelet activation induced by anti-CD9 mAb, which depends upon Fc gammaRII, has been considered to be similar to that induced by Fc gammaRII cross-linking. In this work, we present several lines of evidence to suggest that the mode of platelet activation induced by anti-CD9 mAb is distinct from that induced by Fc gammaRII cross-linking. Ca2+ release from intracellular Ca2+ stores induced by anti-CD9 mAb depended almost totally upon thromboxane A2 production and released ADP, whereas that induced by Fc gammaRII was affected only minimally by these factors. Fc gammaRII cross-linking induced Ca2+ channel opening, which is dependent upon the depletion of intracellular Ca2+ stores. In contrast, anti-CD9 mAb appeared to directly open Ca2+ channels, irrespective of intracellular Ca2+ stores (Kuroda et al., 1995. J. Immunol. 155: 4427). The Ca2+ requirement for the Ca2+ channels opened by Fc gammaRII cross-linking was also distinct from that induced by anti-CD9 mAb. The early phase of Fc gammaRII tyrosine phosphorylation was dependent upon thromboxane A2 production with anti-CD9 mAb-induced activation, whereas that of Fc gammaRII cross-linking was not. p72(syk) and p53/56(lyn) appeared to associate with Fc gammaRII in platelet activation induced by Fc gammaRII cross-linking, whereas there was little, if any, association between Fc gammaRII and these tyrosine kinases in anti-CD9 mAb-induced activation. Piceatannol, a selective inhibitor of p72(syk), enhanced Fc gammaRII tyrosine phosphorylation induced by Fc gammaRII cross-linking, whereas it attenuated the process in anti-CD9 mAb-induced platelet activation. It is suggested that the regulatory mechanism of Fc gammaRII tyrosine phosphorylation differs between these two modes of platelet activation.

Antibodies, Monoclonal↗
PubMed1996

Differential mobilization of tyrosine kinases in human platelets stimulated with thrombin or thrombin receptor agonist peptide.

Both thrombin and thrombin receptor agonist peptide (TRAP) activated p72syk and p60c-src with similar magnitudes. Both thrombin and TRAP induced translocation of p60c-src and p54/58lyn to cytoskeleton in an aggregation-dependent manner. Thrombin also induced cytoskeletal association of p72syk, but independent of platelet aggregation. Furthermore, p72syk associated with cytoskeleton underwent marked proteolysis, which was partially dependent upon calpain activation. In contrast, TRAP, even at concentrations as high as 100 mu M, did not induce p72syk translocation to cytoskeleton. Our findings suggest that cytoskeletal translocation of p72syk induced by thrombin is governed by a mechanism distinct from those of p60c-src and p54/58lyn translocation. It is also suggested that p72syk translocation induced by thrombin requires additional signal(s) other than that mediated by the recently-cloned thrombin receptor that couples with GTP-binding proteins and interacts with TRAP.

Blood Platelets↗