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Biomedical subjects

K Ochiai

Publications and source records attributed to K Ochiai.

324 records · Page 18Linked to original sources

Demonstration of equine herpesvirus-1 gene expression in the placental trophoblasts of naturally aborted equine fetuses.

Equine herpesvirus-1 (EHV-1) infection was demonstrated in the lung tissue of seven aborted fetuses by immunohistochemical labelling and polymerase chain reaction. The placentas of the fetuses were also examined by non-isotopic in-situ hybridization for the EHV-1 glycoprotein B (gB) gene. Positive hybridization signals were observed in the cytoplasm of trophoblasts, especially in microcotyledons, of all seven placentas, and in villous epithelium of the allantochorion of six placentas. Despite the presence of EHV-1 RNA, EHV-1 antigens were not detected in placentas by immunohistochemical examination. The present study represents the first in-vivo demonstration of the EHV-1 gene in equine trophoblasts. The findings suggest direct cell-to-cell spread of EHV-1 from endometrial cells to trophoblasts.

Abortion, Veterinary↗

Distribution of rabbit haemorrhagic disease virus RNA in experimentally infected rabbits.

Adult rabbits were inoculated with liver homogenate from a rabbit that died in a Japanese outbreak of rabbit haemorrhagic disease (RHD). All experimentally infected rabbits died with typical clinical, gross and histological findings of RHD. Distribution of RHD virus in tissues of the infected rabbits was studied by non-isotopic in-situ hybridization. Both viral plus- and minus-strand RNAs were detected within the cytoplasm of hepatocytes, Kupffer cells and splenic and alveolar macrophages, mainly in morphologically intact cells. Strand-specific reverse transcriptase-polymerase chain reaction also demonstrated viral minus-strand RNA as well as plus-strand RNA in the liver, lung and spleen of infected rabbits. These results suggest that viral replication occurs not only in hepatocytes but also in macrophages. The infected macrophages may contribute to viral dissemination in RHD.

Animals↗

Equine herpesvirus-1-induced encephalomyelitis in mice: a comparative study of neuroadapted virus and its parental strain.

Little is known about the neuropathogenicity of equine herpesvirus-1 (EHV-1) in mice. No neurological signs were observed in 6-day-old mice inoculated intracerebrally with the HH1 strain (HH1) of EHV-1. However,6-day-old mice inoculated intracerebrally with a variant derived by serial passage of HH1 in mouse brain showed severe neurological symptoms and eventually died. Histological analyses were performed on 6-day-old mice inoculated with the neuroadapted HH1 (NHH1) and the parental HH1 strain by the intracerebral, intranasal or intraperitoneal route. All routes of inoculation with NHH1 caused encephalitis, but myelitis was observed only in mice inoculated intraperitoneally. Prominent histological findings were perivascular cuffing sometimes associated with small fibrin thrombi, neuronal and glial degeneration and necrosis, and intranuclear inclusion bodies in neurons, glial cells and ependymal cells. Intracerebral and intranasal inoculation, but not intraperitoneal inoculation, with HH1 induced central nervous system (CNS) lesions that were milder than those in mice inoculated with NHH1. The distribution of viral antigen was more widespread in mice inoculated with NHH1 than with HH1. No viral antigen was detected in the CNS of mice inoculated intraperitoneally with HH1. These results indicate that increased viral multiplication and spreading in the CNS were responsible for the enhanced neurovirulence of NHH1. Although EHV-1 has been considered to be primarily endotheliotropic in horses, both NHH1 and HH1 showed tropism for the parenchymal cells of the CNS in mice, namely neurons, glial cells and ependymal cells.

Administration, Intranasal↗

Leiomyosarcoma of the kidney: CT and MR appearance.

A case of leiomyosarcoma of the kidney is reported here with its CT and MRI manifestations correlated to the pathologic findings. The leiomyosarcoma appeared as a well-defined multinodular mass of varying density and signal intensity on CT and MRI, respectively. The low signal-intensity regions on T2-weighted MRI exhibited delayed enhancement on CT and contained more fibrous tissues than did other sites that had more spindle-shaped muscle cells. Knowledge of the MR and CT characteristics may permit radiologists to refine the diagnosis of renal leiomyosarcoma considerably.

Female↗

Recurrent small cell carcinoma of the ovary treated with docetaxel: A case report.

Multiagent chemotherapy for small cell carcinoma of the ovary (SCCO) may contribute to the prolonged survival of young women who are suffering from this disease, even in the advanced stage with remaining tumor, although the rarity of SCCO complicates the generalization of chemotherapy agents and operation methods for this disease. A 24-year-old patient with SCCO FIGO stage IIC is alive after recurrences and chemotherapy including cisplatin + etoposide after the first operation and docetaxel for the second recurrence. She is now doing well with no evidence of disease more than 4 years after the first operation and 2 years after docetaxel treatment. This may be the first report describing the use of docetaxel that may be included in multiagent chemotherapy.

Adult↗

Ultrasonographic appearance of orthotopic ureterocele in a dog.

A three-year-old, intact male, Siberian husky was evaluated for a two day history of dysuria. Sonographically there was an anechoic cyst-like structure in the urinary bladder. The abnormality appeared to be a 'cyst within a cyst', which is a characteristic ultrasonographic feature of ureterocele in humans. Ultrasonography may be a useful means of establishing a diagnosis of ureterocele in dogs.

Animals↗

Signal transduction through interferon-gamma receptor on human eosinophils.

BACKGROUND: We reported on the constitutive interferon-gamma receptor (IFN-gammaR) expression on eosinophils. But signal transduction through IFN-gammaR on eosinophils remains to be elucidated. In this study, we examined the involvement of the Jak/Stat pathway in the signaling of eosinophils after IFN-gammaR conjugation by the ligand binding. METHODS: Purified peripheral eosinophils were stimulated with IFN-gamma at 37 degrees C for 1-60 min. Tyrosine phosphorylation of IFN-gammaR, Jak1, Jak2, and Stat1alpha was examined by immunoblotting. Gel-shift assay was also examined to show the formation of Stat1alpha-DNA complexes. RESULTS: We show that binding of IFN-gamma to human eosinophils initiated a series of events that resulted in the rapid tyrosine phosphorylation of not only the IFN-gammaRalpha chain but also Jak1, Jak2, and Stat1alpha. In addition, IFN-gamma enhanced the DNA-binding activity of Stat1alpha. CONCLUSION: These data indicate that IFN-gamma affects eosinophils through its specific receptor and utilizes the Jak/Stat pathway as its mode of signaling.

DNA-Binding Proteins↗

The role of STAT1 in activation of IL-3- and IL-5-induced eosinophils by interferon gamma.

Tyrosine phosphorylation of STAT1alpha in eosinophils after IFN-gamma stimulation has been shown, but the biological significance of eosinophil STAT1alpha activation in transmitting the signals through the IFN-gamma receptor remains unknown. The purpose of this study is to determine whether STAT1 is involved in the regulation of eosinophils by IFN-gamma-IFN-gamma receptor interaction. rhIL-3- and rhIL-5-induced eosinophils from CD34+ cells of cord blood on day 28 of culture were used. The cells were washed and further incubated in IL-3- and IL-5-free medium for 48 h. The induced eosinophils constitutively expressed CD69 and lost this expression after a further 48-hour incubation without the cytokines. IFN-gamma significantly upregulated CD69 expression on the 48-hour incubated cells. In inhibitory experiments on STAT1, a phosphorothioate oligo antisense DNA against STAT1alpha was added to IL-3- and IL-5-containing medium from day 15 to day 28 of culture. The oligo DNAs altered neither the expressions of myeloid cell marker CD9 and 13 nor the expression of IFN-gamma receptor on the cells. The added STAT1alpha antisense, but not sense, DNA significantly reduced STAT1alpha mRNA expression in the cells. The STAT1 antisense also significantly inhibited IFN-gamma-induced CD69 expression on the 48-hour incubated eosinophils. In conclusion, these results indicate that IFN-gamma induces CD69 expression in the induced eosinophils through STAT1alpha, suggesting that STAT1alpha may play a significant role in eosinophil regulation by IFN-gamma.

Antigens, CD↗

Neurotoxic effects of 2,5-hexanedione on normal and neurofilament-deficient quail.

The neurotoxic effects of 2,5-hexanedione (2,5-HD) were investigated using neurofilament (NF)-deficient (Quv) Japanese quail in comparison with normal Japanese quail. Both Quv and normal Japanese quail were inoculated intraperitoneally with 350 mg/kg/day 2,5-HD for 6 consecutive wk. The results of 2,5-HD exposure differed substantially between the 2 strains of Japanese quail. The 2,5-HD-exposed normal quail showed leg paralysis about 4 wk after initiation of dosing. Some treated normal quail fell into dysstasia and died of nutritional disturbances. Histologically, 2,5-HD-treated normal quail had NF-rich axonal swellings and degeneration in the distal parts of the peripheral nerves, spinal cord, and cerebellar peduncles. In contrast, 2,5-HD-injected Quv quail showed tonic convulsion, ataxia gait, severe quivering, and excitation about 2-3 days after administration. Some treated Quv birds died immediately after systemic tonic convulsion, probably because of asphyxia. Although all treated Quv quail showed neurologic signs, there were no recognizable 2,5-HD-induced lesions in the nervous system. After about 4-6 wk of dosing, 2,5-HD induced distal axonopathy in normal quail and acute neurotoxicity in Quv quail.

Animals↗

Combination therapy with podophyllin and vidarabine for human papillomavirus positive cervical intraepithelial neoplasia.

Our aim was to establish an effective non-surgical treatment for cervical intraepithelial neoplasia (CIN) through inactivation of human papillomavirus (HPV), the major etiological agent for this disease. We show that vidarabine, a DNA polymerase inhibitor, suppressed growth and HPV gene expression in human cervical keratinocytes immortalized by HPV or in cervical cancer cell lines. Expression of HPV-16 E6 and E7 proteins in normal cervical keratinocytes sensitized cells to apoptosis in the presence of podophyllin or vidarabine. We applied vidarabine ointment and/or podophyllin to cervical epithelium in 28 cases of CIN I-II to evaluate the therapeutic effectiveness of these agents. Co-application of vidarabine and podophyllin in six treatments caused regression of lesions cytologically and histologically, and disappearance of HPV-16 or -18 DNA in 17 of 21 (81%) women. Our results suggest that the combination of vidarabine and podophyllin therapy is an effective non-surgical treatment for HPV-positive CIN.

Adult↗

Low specificity of cytokeratin 19 mRNA expression in the peripheral blood cells from patients with ovarian tumors.

We examined CK19 mRNA expression in the peripheral blood mononuclear cells (PBMC) from patients with ovarian tumor by reverse transcriptase-polymerase chain reaction (RT-PCR) using primers which did not cross-amplify pseudogenes of CK19 gene. The incidence of positive CK19 mRNA expression in healthy individuals, benign ovarian tumor patients and ovarian cancer patients were 60% (12/20), 71% (10/14) and 84% (21/25), respectively. Although the frequency of positive CK19 mRNA expression in PBMC from ovarian tumor patients was higher than that from healthy individuals, there was no statistically significant difference between the frequencies. Moreover, one healthy control showed CK19 mRNA expression only in her menstrual period, not in her proliferative phase or secretory phase. These results suggested that CK19 is not a suitable target to detect the presence of tumor cells in the PBMC from patients with ovarian tumors.

Biomarkers, Tumor↗

Effects of concomitant use of doxifluridine, radiotherapy and immunotherapy in patients with advanced cervical cancer.

Clinical effects of doxifluridine (group A, 600 mg/body/day; group B, 800 mg/body/day) combined with radiotherapy and immunotherapy were evaluated in patients with advanced cancer of the uterine cervix. Response rates were 84.2% (16/19 patients) in group A and 100% (18/18 patients) in group B, respectively (p=0.230). There was no significant difference in adverse reaction incidence between the methods but significantly higher grade adverse reaction were observed in group B than in group A (p=0.048). Time to progression (TTP) was longer in group B than in group A (p=0.081). The optimal 5'-DFUR dose was 800 mg/body (group B), by which higher grade adverse reactions were fully controlled and TTP was prolonged.

Adult↗

Esophageal/gastric adenocarcinoma in a dog.

A nine-year-old, intact female, mixed-breed dog was presented with a history of chronic regurgitation and weight loss. Endoscopy and contrast radiography confirmed the presence of a distal esophageal mass. The dog was euthanized, and histopathological diagnosis of the mass was an esophageal/gastric adenocarcinoma.

Adenocarcinoma↗

Interferon gamma and tumor necrosis factor alpha induce Fas expression and anti-Fas mediated apoptosis in a salivary ductal cell line.

BACKGROUND: We previously reported that Fas antigen was strongly expressed on salivary duct epithelial cells and that some salivary infiltrating cells showed the Fas ligand in patients with severe sialoadenitis due to Sjögren's syndrome (SS). Apoptotic changes were observed in ductal epithelial cells and some infiltrating cells by DNA nick end labeling methods. These findings suggest that the Fas-Fas ligand system may play a role in the pathogenesis of sialoadenitis in SS. OBJECTIVE: To elucidate the mechanism of the de novo expression of ductal Fas antigen in sialoadenitis associated with SS, we investigated the induction of Fas antigen and apoptosis by cytokines in a human salivary duct cell line. METHODS: Human salivary duct cell line (HSG) was cultured with interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), interleukin 2 (IL-2), interleukin 4 (IL-4), and granulocyte monocyte colony stimulating factor (GM-CSF). The expression of Fas antigen in HSG was examined by immunoperoxidase cell ELISA. The appearance of DNA strand breaks during apoptosis induced by anti-Fas antibody was detected by DNA nick end labeling methods. RESULTS: Unstimulated HSG cells constitutively expressed low levels of Fas antigen. IFN-gamma and TNF-alpha consistently upregulated constitutive levels of Fas. In contrast, IL-1 beta, IL-2, IL-4, and GM-CSF had no effect on Fas levels. HSG cells expressing Fas antigen in response to IFN-gamma or TNF-alpha were susceptible to apoptosis by anti-Fas antibody. CONCLUSION: Our findings suggest that IFN-gamma or TNF-alpha secreted by infiltrating lymphocytes induces ductal Fas expression and ductal apoptosis in sialoadenitis associated with SS.

Antineoplastic Agents↗

Diverse biological activities of healthy foods.

Diverse biological activities of 7 healthy foods [powdered pine needle, citrate-fermented sesame, powdered coffee, royal jelly, propolis, pollen and white sesame oil (extracted by super critical state (40 degrees C, 350 atmospheric pressure))] were investigated. The pine needle, sesame and powdered coffee was also extracted successively by ethanol and hot water, and lyophilized. The pine needle and coffee extracts, and propolis showed higher in vitro cytotoxic, bactericidal and oxidation activity, as compared with other 4 lipophilic healthy foods. However, propolis showed slightly lower, but significant cytotoxic and bactericidal activity with much reduced oxidation potential. ESR spectroscopy demonstrated that the cytotoxic activity of these extracts was closely related to their radical generation and O2- scavenging activities. Healthy food components may have both pro-oxidant and anti-oxidant properties. Pre-treatment of mice with pine needle, sesame or powdered coffee extract significantly reduced the lethality of bacterial infection, possibly due to their host-mediated action. These extracts failed to reduce the cytophatic effect of HIV-1 (human immunodeficiency virus) infection in MT-4 cells. No apparent acute toxicity was detected in mice by oral administration of 10 g/kg of these extracts. This data suggest the medicinal efficacy of healthy foods.

Animals↗

Combination effect of lignin F and natural products.

We investigated the effect of lignin F, isolated from the alkaline extract of the cone of Pinus parviflora Sieb. et Zucc, on the cytotoxic activity and radical intensity (measured by ESR spectroscopy) of various natural products. Lignin F slightly inhibited the proliferation of human oral tumor cell lines (human squamous cell carcinoma HSC-2, human salivary gland tumor HSG), but not that of human gingival fibroblast HGF, suggesting its tumor specific cytotoxic action. Lignin F enhanced the cytotoxic activity of vitamin K2, vitamin K3, sodium ascorbate (vitamin C), epigallocatechin gallate (EGCG) (a major component of green tea), gallic acid (structural unit of tannin), chlorogenic acid, and 6 tea extracts (Japanese green tea, Japanese barley tea, black tea, Chinese green tea, Chinese Jasmin tea, Chinese Oolong tea), to various extents. On the other hand, lignin inhibited the cytotoxic activity of curcumin and dopamine. ESR spectroscopy demonstrated that combination of lignin and vitamin K3, EGCG or gallic acid synergistically augmented the radical intensity. Lignin F enhanced the bactericidal activity of EGCG against E. coli. These data suggest the beneficial effect of the combination of lignin F and natural products.

Antineoplastic Agents, Phytogenic↗

Pathological study of lead poisoning in whooper swans (Cygnus cygnus) in Japan.

During spring 1989, thirty-three whooper swans (Cygnus cygnus) died at Lake Miyajima in Hokkaido, Japan; 15 were examined. The birds were diagnosed as having subacute lead poisoning due to ingestion of spent lead shot. The main gross findings were bile-stained liver, edematous or gelatinous bone marrow, bile-stained lining with hyperkeratosis and lead pellets in the gizzard, and proventricular impaction. Histopathologically, there was lead-hemolytic jaundice of the liver, hemosiderosis in the liver and spleen, and hypoplasia of the bone marrow with increased numbers of polychromatic erythroblasts. Acid-fast intranuclear inclusion bodies were seen in kidneys of seven swans. Under electron microscopy, inclusion bodies had frayed contours and consisted of high-electron-dense fine granules. The lead concentration of the liver ranged from 5.5 to 44.3 mg/kg wet weight. It was suggested that these changes resulted from excess breakdown of erythrocytes, inhibition of heme synthesis, and impaired erythropoiesis caused by lead shot.

Animals↗

Intrahepatic peripheral cholangiocarcinoma: two-phased dynamic incremental CT and pathologic correlation.

To elucidate the characteristic CT findings of intrahepatic peripheral cholangiocarcinoma, two-phased dynamic incremental CT scans of 20 cholangiocarcinomas in 16 patients were carefully analyzed. Dynamic incremental CT scanning was performed after intravenous administration of 100 ml iodinated contrast medium at a rate of 2 ml/s using a power injector. The CT scans (8-16 sections) were obtained during 45-110 s (early phase) and 6-7 min (delayed phase) after commencement of the injection of the contrast medium. On CT, 55% (11 of 20) of intrahepatic peripheral cholangiocarcinomas appeared hypodense in both phases. Most of the tumors (80%) appeared hypodense in the early phase and had increased CT numbers in their delayed images. Lymphadenopathy was observed in 69% (11 of 16) of patients whose main tumors exceeded 3 cm in diameter. All tumors appeared irregular or indistinct. Twenty percent (4 of 20) of the cholangiocarcinomas were difficult to distinguish from hepatocellular carcinomas or hemangiomas.

Adenoma, Bile Duct↗