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Biomedical subjects

I Shibata

Publications and source records attributed to I Shibata.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Changes of regional perfusion in metastatic brain tumor and peritumoral area after radiosurgery: a study by 123I-IMP dynamic SPECT].

Changes of regional perfusion in the tumor, peritumoral edematous area and juxtatumor brain after radiosurgical treatment for metastatic brain tumor were investigated by dynamic SPECT using 123I-IMP. The SPECT was performed in 12 patients before and 1, 7 and 30 days after stereotactic irradiation. A region of interest (ROI) was selected each in the tumor, peritumoral edematous area, juxtatumor brain and ipsilateral cerebellum. Radioactivity in each ROIs was counted on early SPECT based on dynamic SPECT from 0 to 5 minutes. Mean count/pixel in each ROIs was divited by mean count/pixel in the ROI of the ipsilateral cerebellum and its value was designated as a count ratio (CR). Assuming the pre-treatment CRs are 1.0, relative changes of post-treatment CRs investigated. rCR in the tumor did not show any significant change after radiosurgical treatment. rCR in the edematous area and the juxtatumor brain increased at 7 days after irradiation [Mean +/- SD 1.43 +/- 0.409 (p < 0.05), 1.248 +/- 0.228 (p < 0.05) by Mann-Whitney test] and at 30 days [1.359 +/- 0.245 (p < 0.01), 1.301 +/- 0.287 (p < 0.01)] respectively. Computed tomography revealed no change in the maximum diameter of the tumor at 1 month after irradiation but a significant reduction in the diameter [0.744 +/- 0.227 (p < 0.02)] at 2 months. Early improvement of regional cerebral blood flow in the juxtatumor areas after radiosurgery suggested that radiosurgery could be effective treatment for metastatic brain tumor.

Adenocarcinoma↗
PubMed1996

[High uptake of N-isopropyl-p-[123I]-iodoamphetamine (123I-IMP) demonstrated by dynamic SPECT in some cases of glioma].

Selective high uptake of N-isopropyl-p-[123I]-iodoamphetamine (123I-IMP) in the brain tumors is not common, the mechanism of uptake in the brain tumor is not yet clearly understood. Among 26 cases of gliomas investigated by dynamic SPECT, 4 cases including 2 cases of anaplastic astrocytoma and 2 cases of oligodendroglioma, showed high uptake of 123I-IMP. New three detector type camera which enables us to investigate rapid successive scanning, was used in our study. In dynamic SPECT, 15 successive scans of 2 minutes interval were made for 30 minutes after administration of 123I-IMP. In addition, quick dynamic SPECT was tried in 2 cases, in which 10 quick successive scans of 24 seconds interval were investigated for initial 4 minutes immediately after administration of 123I-IMP. Radioactivity in the region of interest inside the tumor (T) and radioactivity of the corresponding site in the contralateral hemisphere (C) was measured respectively, and T/C ratio was calculated. Time course change of radioactivity (time activity curve: TAC) was analyzed in all cases. Radioactivity was always higher in the tumor and the average T/C ratio was 1.40. TAC showed rapid increase of 123I-IMP in the tumor during initial 2 minutes after administration and keeping its high plateau level for 30 minutes. Angiography in these cases revealed a remarkable tumor stain. On the other hand, these gliomas showed no or slight enhancement effect in CT or MRI. These findings are interpretable as that early high uptake of 123I-IMP in some gliomas is attributable to an increased vascular bed and blood flow with no or minimal derangement of blood brain barrier in these tumors.

Adult↗
PubMed1995

Experimental infection of SPF piglets with porcine reproductive and respiratory syndrome (PRRS) viruses isolated from two farms.

Porcine reproductive and respiratory syndrome (PRRS) viruses were isolated from pig samples obtained from two farms characterized by an increased number of stillbirth and high mortality in new-born piglets (farm A), and respiratory distress with high mortality in weaning and growing pigs (farm B) in 1993, respectively. When primary specific pathogen-free piglets, 5-day-old or 13-day-old, were experimentally inoculated with the isolates, they showed clinical signs of depress, anorexia, pyrexia, diarrhea, sitting posture and periocular edema. Rate of the weight gain was reduced in the inoculated piglets compared with the non-inoculated pig. There were no apparent differences in clinical signs between the piglets inoculated with the virus samples derived from farms A and B. Microscopically, the most prominent changes observed in experimentally inoculated piglets were interstitial pneumonia, nonpurulent myocarditis and catarrhal lymphnoditis post inoculation day (PID) 28. Viruses were recovered from tissues collected from the inoculated piglets on PID 7 or 28. Furthermore, the viruses were continuously recovered from the sera from PID 7 to PID 28. Antibodies measured by indirect immunofluorescence assay to PRRS virus were first detected in sera on PID 14, and the antibody titer rose to 1:1280 on PID 28.

Animals↗
PubMed1995

[The use of TM HAKEN plate in craniofacial surgery].

Rigid internal fixation using mini/micro plate has become a frequent application in cranio-maxillo-facial surgery. In order to make plate fixation easier and reduce operative time, the TM HAKEN plate, a kind of micro plate, was devised which has a thorny HAKEN like an ice pick and applied to cranio-facial surgery. The plate is made of titanium, and th HAKEN and screw are made of titanium alloy. These allow contoured engagement in all three dimensions due to the flexibility of titanium, and firm fixation due to the physical strength of titanium alloy, resulting in minimized artifact on CT scan and MRI images. The fixation is accomplished by just driving in the plate with a hammer, and using screws. In the case of wide operative field, the plate is driven in directly, while in the case of small field, the plate is driven in with an impactor. TM HAKEN plate has been used for osteosynthesis in 39 cases of craniofacial surgery at the Department of Plastic and Reconstructive Surgery of Toho University Hospital between September 1992 and September 1994. Of the 39 cases, 19 were cranioplasty using frozen preserved auto-carvarial bone, 9 were midface fractures, 6 were fixation of free bone grafting, and 5 were fixation of artificial bone (hydroxyapatite-tricalcium phosphate composite ceramics) grafting. Satisfactory results were obtained in all cases without any difficult complications such as infection, exposure or migration. In addition, reliable post-operative evaluations and follow-ups were possible with reduced artifact on CT scan and MRI images.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Plates↗
PubMed1994

Replication of virulent and attenuated strains of Aujeszky's disease virus in swine alveolar macrophages.

In vitro and in vivo replication of Aujeszky's disease virus (ADV) in swine alveolar macrophages (AM) was studied using two virulent strains and a vaccine strain with deletions in the thymidine kinase and gIII genes. In vitro, AM were highly permissive to virulent ADV infection. Virus progeny titers of virulent strains in the cell phase and in the fluid phase were higher than 10(7.3) TCID50/ml at 84 hr post-inoculation (PI). For vaccine strain infection, AM were less permissive, yielding virus titers of 10(2.3) TCID50/ml at 84 hr PI. To study in vivo replication of ADV in AM, virus isolations were made from AM collected at intervals from pigs inoculated intranasally with both the virulent and vaccine strains. Virus was isolated from AM samples collected from all pigs infected with the virulent strain from days 2 to 22 PI. On the contrary, no virus was detected in AM samples collected from pigs infected with the vaccine strain. The results presented suggested that in vivo virulent ADV replicates for a relatively long period in swine alveolar macrophages.

Animals↗
PubMed1993

A serological survey of encephalomyocarditis virus infection in pigs in Japan.

A total of 1502 pig sera collected between 1990 and 1991 at 65 farms in 22 prefectures were subjected to neutralization test to encephalomyocarditis (EMC) virus. Of them, three hundred eighty seven pigs (25.8%) from the 55 farms (84.6%) had antibody against EMC virus. The positive rates were rather high in Ehime (53.1%), Tottori (49.1%), Shimane (44.4%) and Nagasaki (38.7%). The positive rate and geometric mean titer of antibody tended to increase with the age. These serological results suggest that the EMC viral infection have been occurred among pigs in Japan.

Age Factors↗
PubMed1993

Experimental pneumonia of pigs infected with Aujeszky's disease virus and Actinobacillus pleuropneumoniae.

Experimental infections were induced out to examine whether Aujeszky's disease virus (ADV) infection in pigs results in a severe pneumonia by Actinobacillus pleuropneumoniae. Intranasal inoculation of ADV (10(6.9) median tissue culture infective dose/head) in 4-month-old primary specific-pathogen-free pigs was followed by the inoculation of A. pleuropneumoniae type 1 (10(3.1) or 10(5.1) colony-forming-units/head). The pigs inoculated with ADV alone developed clinical signs of Aujeszky's disease but not pneumonia, and those inoculated with A. pleuropneumoniae (10(3.1) CFU/head) alone did not develop clinical symptoms and lung lesions. Whereas all the pigs inoculated dually with ADV and A. pleuropneumoniae (10(3.1) CFU/head) showed severe or very severe clinical symptoms and moderate or severe pneumonia and one of them died. The pigs inoculated with A. pleuropneumoniae (10(5.1) CFU/head) alone had severe clinical symptoms and one of the 2 pigs died acutely. Furthermore, all of the 3 pigs inoculated with ADV and A. pleuropneumoniae (10(5.1) CFU/head) showed clinical symptoms and moderate or severe pneumonic lesions and one pig died of disease. It was concluded that the clinical symptoms of A. pleuropneumoniae became severer by concomitant infection with ADV.

Actinobacillus pleuropneumoniae↗
PubMed1993

Distinction between Aujeszky's disease virus-infected and vaccinated pigs by hemagglutination-inhibition test.

A hemagglutination-inhibition (HI) test was applied to distinguish virulent Aujeszky's disease virus infected pigs from those immunized with a glycoprotein gIII deletion vaccine. The vaccine strain, dlg92/dltk, did not have hemagglutination activity with mouse erythrocytes and the pigs vaccinated five times with the dlg92/dltk strain failed to develop HI antibody, although they developed neutralizing antibody with 128 to 512 titers to Aujeszky's disease virus. On the other hand, these pigs produced HI antibody 1 to 2 weeks after virulent virus inoculation. Thus the animals infected with virulent strain were easily differentiated from the animals immunized with the gIII deletion vaccine.

Animals↗
PubMed1993

Effect of heparin on hemagglutination by pseudorabies virus.

Heparin inhibited hemagglutination (HA) by pseudorabies virus (PRV), but not HA by Akabane virus, bovine adenovirus type 7, Fukuoka virus, Getah virus, Japanese encephalitis virus, and parainfluenza virus type 3 belonging to the families Bunyaviridae, Adenoviridae, Rhabdoviridae, Togaviridae, Flavivi-idae, and Paramyxoviridae, respectively. The minimal inhibitory concentration of heparin required to inhibit 8 HA U of PRV ranged from 0.005 to 0.01 U/ml. Mouse erythrocytes failed to combine with the HA inhibitory factor of heparin. On the other hand, mouse erythrocytes treated with heparinase had greatly reduced agglutinability by PRV. Virus-heparin complex formation could be observed by sedimenting heparin with the virus particles.

Animals↗
PubMed1992

Multiplication and immunogenicity of a temperature-sensitive and thymidine kinase-deficient strain of Aujeszky's disease virus in pigs.

Hysterectomy-produced colostrum-deprived 5- and 27-day-old pigs were inoculated intramuscularly (IM) or intranasally (IN) with the temperature-sensitive and thymidine kinase-deficient ZHtsTK- strain of Aujeszky's disease virus (ADV), and the nasal swabs and organs of the pigs were periodically collected for virus isolation. No abnormal clinical signs were observed in these pigs, except for a mild febrile response. Viral shedding in the nasal swabs with low titers was detected in the pigs inoculated IN between postinoculation day (PID) 1 and 5, but not in those of the pigs inoculated IM. No contact infection, however, occurred in the cohabiting pigs. Viruses with low titers were isolated only from the muscles and lymph nodes at the site of inoculation in the pigs inoculated IM on PID 2 and 4, but not from any organs of the pigs inoculated IN. To investigate the ability of the ZHtsTK- strain to establish a latent infection in pigs, the pigs inoculated IM or IN with the ZHtsTK- strain were treated with prednisolone. No virus was detected in the trigeminal ganglia or the nasal swabs collected after prednisolone treatment by the cocultivation method. The immunological evaluation demonstrated that immunization of pigs with this strain was effective in preventing clinical signs caused by ADV infection. The duration of virus shedding was markedly shortened in immunized pigs, particularly in those immunized twice and the total quantity of virus recovered from immunized pigs was reduced in comparison with unimmunized pigs.

Animals↗
PubMed1992

Characterization of Japanese isolates of Aujeszky's disease virus by restriction endonuclease cleavage patterns, virulence in mice and thymidine kinase activity.

Twenty four cloned isolates of Aujeszky's disease virus collected from outbreaks of Aujeszky's disease from 1981 through 1989 in Japan were characterized by their restriction endonuclease (RE) cleavage patterns, virulence for mice and thymidine kinase (TK) activity. All of the isolates belonged to Type II of the four types classified by Herrmann et al. (1984). Based on the number and migration rate of the restriction fragments, the isolates were divided into 7 groups with Bam HI, 9 groups with Kpn I, 3 groups with BstE II and 2 groups with Sal I. The results indicate that the RE analysis, especially with Bam HI and Kpn I, provides useful epidemiological information about field isolates of Aujeszky's disease virus. All of the isolates showed virulence for mice ranging from 6.9 to 63.0 (PFU/LD50). It was interesting that the Nagano S87 strain, which had the highest virulence for the mouse, showed unique RE cleavage patterns with four enzymes. On the other hand, ara-T-resistant, TK-negative strain, was avirulent for mice (greater than 10(6.4) PFU/LD50). All of the isolates investigated in this study showed TK activity by the thymidine plaque autoradiography.

Animals↗
PubMed1991

Avirulent ts and thymidine kinase-deficient mutant of Aujeszky's disease virus.

The temperature-sensitive (ts), thymidine kinase-deficient (TK-) mutant designated ZHtsTK- strain, of Aujeszky's disease virus (ADV) was isolated from a virulent strain with the treatments using 5-bromodeoxyuridine and arabinosylthymine. The ZHtsTK- strain was easily distinguished from the other virulent ADV strains by plaque size on HmLu-1 and chicken embryo fibroblast cells and by restriction endonuclease analyses using Bam HI, Sal I and Kpn I. The ZHtsTK- strain was avirulent for mice, guinea pigs and rabbits, and produced neutralizing antibodies to ADV in these animals. The rabbits inoculated with the ZHtsTK- strain did not shed detectable amounts of virus after dexamethasone treatment. The ZHtsTK- strain was also avirulent for 5-day-old piglets and did not cause disease. No virus was detected from the piglets inoculated intramuscularly in the nasal swabs or the tissues examined on postinoculation day 9. These findings presented here suggested that there is a significant correlation between pathogenicity and properties such as ts and TK-, and the combination of ts and TK- properties plays a much larger role in reducing virulence for animals.

Animals↗
PubMed1991

Physicochemical properties of pseudorabies virus hemagglutinin.

Pseudorabies virus hemagglutinin was readily adsorbed on mouse erythrocytes at 4, 22, or 37 degrees C, but not on cattle erythrocytes. The adsorbed hemagglutinin could not be eluted from the cells by resuspending in phosphate-buffered saline (PBS), by incubating at 37 or 50 degrees C, or by incubating in the presence of neuraminidase. The receptor on mouse erythrocytes for the hemagglutinin was inactivated by trypsin, but not by neuraminidase, sodium deoxycholate (DOC), potassium periodate (KIO4), dithiothreitol (DTT), 2-mercaptoethanol (2-ME) and formalin. The hemagglutinin was inactivated by trypsin, alpha-amylase, pepsin, DOC, KIO4, and ethylendiamine-tetraacetic acid (EDTA), but not by papain, beta-glucosidase, phospholipase C, neuraminidase, DTT, 2-ME, Tween-80, ethylether, chloroform, trichloro-trifluoroethane, beta-propiolactone and formalin, suggesting that the hemagglutinin active component involved glycoproteins. The hemagglutinin was stable at 37 degrees C for lower temperatures but not at 60 degrees C or higher. The hemagglutinin activity was resistant to ultraviolet irradiation, while the infectivity was very susceptible. The hemagglutinin and the infectivity were readily sedimented by ultracentrifugation at 48,000 x g for 3 hr. In rate zonal centrifugation of the preparation on a sucrose density gradient, the hemagglutination (HA) activity showed a sharp peak at 1.22 g/ml coinciding with the peak of infectivity. The HA activity in the peak fraction seemed to be structually associated with virus particles. After fractionation of the virus by Nonidet P-40, the HA activity was found only in the fraction of the envelope material, indicating that the hemagglutinin is situated in the viral envelop.

Adsorption↗
PubMed1991

Pharmacokinetic study of selective continuous internal carotid CDDP infusion in malignant brain tumors.

Cis-diamminedichloroplatinum (CDDP) was administered by selective continuous internal carotid infusion to nine patients with malignant brain tumors, including five glioblastomas, one mixed glioma, and three metastatic tumors. CDDP was infused through a catheter in the internal carotid artery at 100 mg/hr in all cases, except one glioblastoma case in which the lower rate of 10 mg/hr was used. The results of CDDP concentration measurements were: 1) CDDP in the blood peaked at termination of CDDP infusion and then decreased slowly, 2) CDDP infiltrated intratumoral cysts and accumulated there, 3) CDDP in the cerebrospinal fluid peaked 6-18 hours after infusion, and 4) the tumor/plasma CDDP ratio varied from 2 to 8. The size of tumors decreased moderately in three of the nine cases, but no complete response was achieved. The histological changes due to CDDP were observed in the tumor tissue and were absent in the normal brain parenchyma.

Adult↗
PubMed1991

[An immunohistopathological study on intrahepatic distribution of HBeAga/b in biopsied chronic type B hepatitis].

In order to evaluate the role of a expression of HBV-associated, we investigated histological and cytological distribution of HBeAga, HBeAgb, and HBcAg by immunoperoxidase procedure using monochronal antibodies. Materials submitted for this study were needle biopsied specimens obtained from 41 chronic carriers and serial paraffin sections were used for the immunohistological study. The localization of HBeAga/b antigens was limited in hepatocellular nuclei, and hepatocellular cytoplasm was HBeAg negative, HBeAg was detected in 11 cases (33%) of 33 cases with chronic active hepatitis (CAH) and in 5 cases (63%) of 8 cases with chronic inactive hepatitis (CIH). Among the HBeAg positive 16 cases, HBeAgb was demonstrated in 15 cases, however, HBeAga was revealed only each one case of CAH and CIH, respectively. Most of HBeAg positive cells were distributed in the peripheral zone of the hepatic lobules while the positive cells were found in central to midzonal zones of 3 cases CAH and one case of CIH. All in histopathologically HBeAga/b positive cases were also HBeAg positive serologically. On the other hand, in HBeAg sero-positive patients, histological positive rate of HBeAga/b was in 33% in CAH and 50% in CIH.

Biopsy↗