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Biomedical subjects

Y Yoshikawa

Publications and source records attributed to Y Yoshikawa.

At least 361 records · Page 20Linked to original sources
PubMed1984

Oncogenecity of an avian erythroblastosis virus in mutant strains of Japanese quails.

The susceptibility of 12 mutant strains of Japanese quails to the R strain of avian erythroblastosis virus (AEV) was examined. Three strains, SBPP, PNN and CWE, showed high susceptibility and developed various types of tumors including erythroblastosis, hemangioma and myeloblastic leukemia. In relatively resistant WE strain, increased incidence and various types of tumors were observed by modification of host conditions. These results indicate pluripotential oncogenicity of AEV in quails as well as partial control of AEV-oncogenesis by genetical background of the host.

Alpharetrovirus↗
PubMed1984

Lysis of horse red blood cells mediated by antibody-independent activation of the alternative pathway of chicken complement.

Horse red blood cells (HRBC) were found to be lysed when incubated with fresh normal chicken serum (NCS). By comparison of the properties of the lysis of HRBC with those of the complement-dependent lysis of sheep red blood cells (SRBC) sensitized with haemolytic antibody via the classical pathway, the following differences were observed between the two haemolytic phenomena. (i) The lysis of HRBC was independent on antibody in contrast to the antibody dependence of the lysis of sensitized SRBC. (ii) The lysis of HRBC was dependent on Mg but not on Ca ion, whereas the lysis of sensitized SRBC required both Mg and Ca ions. (iii) Treatment of NCS with carrageenan that acts as an inactivator of the first component of complement (C1) inhibited the lysis of sensitized SRBC but not the lysis of HRBC. (iv) C1 was consumed in the lysis of sensitized SRBC but not in the lysis of HRBC. (v) Cobra venom factor (CVF), C3 inactivator via the alternative complement pathway, inhibited the lysis of HRBC but not the lysis of sensitized SRBC. (vi) Minimal reaction times for the lysis of HRBC and for the lysis of sensitized SRBC were 90 and 60 min, respectively. These findings indicate that the lysis of HRBC was caused by the antibody-independent activation of complement via the alternative pathway.

Animals↗
PubMed1983

Renal papillary necrosis associated with Wegener's granulomatosis.

Review of the kidneys from 23 cases of Wegener's granulomatosis revealed necrosis of the renal papillae in five (21.7 per cent). These cases took a fulminant course of the disease consistent with the classic description of Wegener's granulomatosis, prevalence in the older age group, and rapid deterioration of renal function. Morphologic examination of the kidneys uniformly disclosed a variety of lesions in the blood vessels supplying the renal papilla. The most conspicuous was the widely distributed glomerular lesion represented by thrombotic and necrotic occlusion of capillary loops and crescent formation. A medullary interstitial lesion characterized by fibrinoid necrosis of the vasa recta was invariably found in the outer portion of the necrotic papilla. In addition, acute segmental and diffuse necrosis and occlusion by thrombosis were identified in the branches of spiral arteries in the adjoining papilla. The results provide an anatomic basis for the assumption that papillary ischemia due to impairment of the dual blood supply from the vasa recta and the calyceal arteries is the essential factor in papillary necrosis.

Adolescent↗
PubMed1983

Characterization of canine distemper viruses adapted to neural cells and their neurovirulence in mice.

Interaction of the Onderstepoort strain of canine distemper virus (CDV) with three established human neural cells, i.e. IMR-32 neuroblastoma, 118-MGC glioma and KG-1 oligodendroglioma, was examined, and adaptation of CDV to these cells was also attempted. The unadapted virus was found to grow at relatively low titers in the three neural cells inducing moderate to minimal cytopathic effects (CPE). The virus was successfully grown at high titers in these cells after 8 to 10 passages. Biological characteristics such as growth rate, morphology of CPE and plaque size changed after adaptation. Analysis by SDS-polyacrylamide gel electrophoresis, however, failed to show any difference in the molecular weight of component proteins among the unadapted and three adapted viruses. Inbred DDD strain of mice developed clinical signs after intracerebral inoculation with the unadapted virus but most of them survived with histological lesions of encephalitis. Neuroblastoma-adapted virus induced only transient clinical signs in some animals with mild encephalitic lesions in the gray matter. Increases in neurovirulence were found for viruses adapted to glioma and oligodendroglioma cells. Almost all mice inoculated with these two viruses at 3 weeks of age died within 8 days with histological lesions consisting of hyperemia, edema, severe degeneration of nerve cells and a few giant cells. Demyelinating lesions in the absence of inflammatory changes were observed in the cerebellum, pons and medulla oblongata of animals inoculated with oligodendroglioma-adapted virus.

Animals↗
PubMed1983

Activation of chicken alternative complement pathway by fowlpox virus-infected cells.

Fresh normal chicken serum (NCS) which lacked virus-neutralizing antibody to fowlpox virus (FPV) was found to inhibit the appearance of the cytopathic effect of the virus, virus growth, and plaque formation in chicken embryo cells. Immunofluorescent examination revealed the deposition of the third component of complement (C3) on FPV-infected chicken embryo cells incubated with fresh NCS. The inhibitory activity of fresh NCS on viral cytopathic effect was independent of the Ca2+ ion and was abrogated by treatment of fresh NCS with inulin or zymosan. Similarly, deposition of C3 on FPV-infected cells occurred independently of the Ca2+ ion and was inhibited by treatment of fresh NCS with inulin or zymosan but was not inhibited by absorption with FPV-infected cells. These results suggest that antibody-independent activation of complement by FPV-infected cells via the alternative pathway caused the inhibition of the virus growth as well as the C3 deposition. Involvement of complement activation as nonspecific host response to virus infection was also suggested by the demonstration of the C3 deposition in the skin lesions of FPV-infected chickens.

Animals↗
PubMed1983

Isolation and identification of the third component of complement of Japanese quails.

The identification of the third component of complement (C3) of Japanese quails was attempted by using rabbit antiserum prepared against quail serum-treated zymosan (ZX) as an initial reagent. This antiserum (anti-ZX) had agglutinating activity on rabbit erythrocytes reacted with quail antibody and quail complement (EACq) but not on EAq, and developed two precipitin lines against quail serum at beta- and gamma-regions in crossed immunoelectrophoresis. Subsequently, monospecific antisera to each of these precipitin lines were prepared in rabbits, and quail serum proteins reactive with these antisera were purified by salt precipitation followed by Sephadex gel filtration and DEAE cellulose column chromatography. One protein with a m.w. of 184,000 (184K) resembled mammalian C3 in that: 1) monospecific antiserum (anti-184K protein serum) agglutinated EACq but not EAq; 2) treatment of fresh quail serum with either inulin or zymosan resulted in the conversion of the precipitin line developed against 184K protein from gamma to beta in crossed immunoelectrophoresis; 3) the 184K protein was shown to consist of two polypeptide chains of 110K and 73K linked by disulfide bonds. Furthermore, the 184K protein in serum was cleaved through the incubation with inulin to 174K and 140K proteins that might correspond to C3b and C3c of human complement; 4) the 184K protein bound to zymosan was eluted with hydrazine or methylamine but not with Nonidet P-40, indicating that 184K protein binds to zymosan by a covalent bond but not by a hydrophobic one; and 5) by treatment of fresh quail serum with methylamine, complement reactivity was reduced, although its activity was restored by the addition of purified 184K protein. These results suggest the 184K protein is the quail's equivalent to mammalian C3. When quail serum was reacted with cells that had complement-activating capacity, quail C3 deposited on their membrane as in mammalians; however, no conversion of quail C3 was noted by the reaction with CVF. Antibody to quail C3 failed to cross-react with that in mammals.

Animals↗
PubMed1983

Possible antiarrhythmic activities of trapidil.

Possible antiarrhythmic activities of 5-methyl-7-diethylamino-s-triazolo(1,5-a)pyrimidine (trapidil, Rocornal) were investigated in vitro and in vivo. Trapidil significantly increased the amount of aconitine or ouabain needed for production of ventricular arrhythmias in rats and guinea pigs. Trapidil also produced a significant increase in threshold current of electrical stimuli which induced ventricular tachycardia in dogs under acute myocardial ischemia. Electrophysiological examinations on effects of trapidil on isolated rabbit ventricular muscle cells showed shortening of the action potential duration (APD) and prolongation of the effective refractory period (ERP), resulting in an increase in the ratio of ERP/APD. The results indicate that trapidil will have a possible effectiveness in inhibiting ventricular arrhythmias.

Aconitine↗
PubMed1982

Effective treatment of the postoperative maxillary cyst by marsupialization.

The postoperative maxillary cyst occurs as a delayed complication after radical surgical intervention in the maxillary sinus. The recommended procedures for treating this entity have been enucleation followed by formation of an antronasal window, primary closure, or open packing. To prevent recurrence and unnecessary tissue destruction from surgery, marsupialization was performed in eight unilocular postoperative maxillary cysts. With the exception of a case in which the long-term results could not be obtained, the cysts disappeared in four months to two and a half years. Possible indications for marsupialization of the postoperative maxillary cyst are discussed.

Adult↗
PubMed1982

Japanese quail embryo cell line persistently infected with erythroblastosis virus.

A Japanese quail embryo cell line transformed by avian retrovirus, designated QERC-31F, was further characterized in virological and cytological aspects. Infectious virus produced by this cell line was found to belong to subgroup A. The virus failed to transform quail embryo cells, whereas it induced erythroblastosis by injection into neonatal quails. Injection of QERC-31F cells into neonatal quails resulted in the induction of solid tumors which morphologically diagnosed as undifferentiated sarcoma. Mitosis of pro-erythrocytic cells with also detected in the peripheral blood of the tumor bearing animals. Antiserum to chicken erythrocyte histone V fraction which was also shown to react specifically with the nucleus of quail erythrocytes stained the nucleus of QERC-31F cells. These results suggested that this cell line maintains characteristics of the erythroblast and possibly produces avian erythroblastosis virus as well as helper virus of subgroup A.

Alpharetrovirus↗
PubMed1981

Bilateral renal dysplasia accompanied by pancreatic fibrosis, meconium ileus, and situs inversus totalis.

An autopsy case of bilateral renal dysplasia with other congenital malformations is reported. Malformations included severe pancreatic fibrosis with meconium ileus, situs inversus totalis, cardiovascular anomalies, and others. The only syndrome of multiple congenital malformations involving renal dysplasia which is similar to the present case is Ivemark's syndrome, though the present case lacked hepatic lesions. Apart from the pancreatic lesion, there were no abnormalities compatible with cystic fibrosis (mucoviscidosis). It was considered that meconium ileus in the present case was caused by pancreatic achylia secondary to severe pancreatic fibrosis, unrelated to cystic fibrosis, but closely allied to renal dysplasia.

Abnormalities, Multiple↗
PubMed1981

Depressant effect of trapidil on dog coronary arterial contraction induced by ergonovine.

Effects of trapidil on ergonovine-induced contractions of isolated dog coronary arteries were investigated in vitro. Ergonovine produced dose-dependent contractions of helical strips cut from the left circumflex branches of coronary arteries. Trapidil significantly depressed these-contractions. 5-HT also produced dose-dependent contractions of the strips, which were depressed by trapidil. In isolated rabbit femoral arterial preparations, norepinephrine dose-dependently contracted the strips. Phentolamine significantly depressed these contractions, and trapidil depressed them when relatively high doses were applied previously. Results indicate that trapidil has a depressant effect on coronary arterial contractions induced by ergonovine, partly through antagonism to 5-HT receptor and/or adrenergic alpha receptor.

Animals↗
PubMed1981

Suppression of delayed hypersensitivity by measles virus infection in guinea pigs.

A guinea pig model of mild measles virus infection was established by the intranasal inoculation with Toyoshima strain. The infection was confirmed by the development of both humoral and cell-mediated immunities to measles virus as well as by the demonstration of transient virus growth in the lymphoid tissues. The virus infection caused a transient suppression of delayed hypersensitivity to purified protein derivative (PPD) at both the induction and expression phases, whereas Jones-Mote-type hypersensitivity to ovalbumin developed in a normal fashion. In the virus-infected animals, the suppressed response to the skin reacting factor was observed as well, however in vitro responsiveness of lymphocytes to PPD was not suppressed. On the other hand, transient enhancement of skin reactivity to phytohemagglutinin by virus infection was noticed. These results may indicate subtle alterations of immune functions in guinea pigs during measles virus infection.

Animals↗