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Biomedical subjects

T Moriya

Publications and source records attributed to T Moriya.

At least 163 records · Page 9Linked to original sources
PubMed1996

Epstein-Barr virus-associated post-transplant primary smooth muscle tumor of the liver: report of an autopsy case.

Epstein-Barr (EB) virus-associated primary smooth muscle tumors have been reported in immunosuppressed young patients with acquired immunodeficiency syndrome (AIDS) and young people who have undergone liver transplantation. An autopsy case of EB virus-associated smooth muscle cell tumor in a 21 year old female who received immunosuppressive therapy following renal transplantation is reported. Multiple tumor nodules were present in the liver, but no primary lesion was found in any other organ. Histologically, the nodules were composed of spindle cells, positive for alpha-smooth muscle actin, which were arranged in fascicles and closely associated with vascular channels, thereby suggesting a vascular smooth muscle cell origin. EB virus infection of the tumor cells was clearly demonstrated by in situ hybridization with an EB virus-encoded RNA 1 (EBER-1) probe. The present case illustrates that EB virus infection may play some role in the development of smooth muscle tumors not only in immunocompromised young patients with liver allografts, but also in those with renal allografts.

Adult↗
PubMed1996

Cryopreservation of semen from Japanese white rabbits for use in teratological studies.

Cryopreservation of semen from Japanese White rabbits was examined to reduce the number of their males for use in teratological studies. Semen was frozen with liquid nitrogen, preserved, thawed, and tested for motility according to the method of Chen et al. Even after cryopreservation an average of 52% of the thawed sperms were motile. In a previous study, frozen- thawed sperms with a motility of 40% resulted in a high conception rate (approximately 88%) on artificial insemination when New Zealand White rabbits were used [5]. These results indicate the possibility that cryopreservation of semen from Japanese White rabbits may be used in teratological studies to reduce the number of males.

Animals↗
PubMed1996

Very low incidence rates of community-acquired hepatitis C virus infection in company employees, long-term inpatients, and blood donors in Japan.

To assess the contemporary rate of hepatitis C virus (HCV) propagation in Japanese community, we conducted a sentinel study on three groups of people: company employees, long-term inpatients, and blood donors. A total of 3079 company employees negative for anti-HCV were followed thereafter, and seroconversion to anti-HCV was found in 5 per 5786 person-years. None of them was positive for HCV RNA. In the group of 703 long-term inpatients (25 of whom were initially positive for anti-HCV) none showed seroconversion to anti-HCV per 2712 person-years. As for 114,266 repeated blood donors who were initially antibody-negative, 227 became anti-HCV positive later. Of these seroconverted donors, 83 were found to have anti-HCV with titers of 2(6) or greater. HCV RNA was positive in only 3 of them. Thus, the incidence rates of acquired HCV viremia in these three groups were 0 for both company employees and long-term inpatients, and 1.78 (95% C.I.: 0.37-5.19) per 100,000 person-years in blood donors. These results suggest that community-acquired HCV infection is now rare in Japan, and that even if it occurred it hardly leads to persistent viremia.

Adolescent↗
PubMed1995

Clinical implications of metastases to the ovary.

Predictive factors for ovarian metastases were analyzed in 313 autopsy cases of women dying of malignancy. Genital, hematopoietic, brain tumors, and double primaries were excluded. Ovarian metastases were found in 60 of 313 (19.2%) cases. The primary sites of origin were stomach (18 cases), breast (13), pancreas (7), bile duct (7), large intestine (4), kidney (3), liver (2), lung (1), and other (5). The percentages of ovarian metastasis in each primary site were 50% (3/6) in the kidney, 38.3% (18/47) in the stomach, 30.8% (4/13) in the large intestine, 22.9% (13/57) in the breast, 22.6% (7/31) in the bile duct, 19.4% (7/36) in the pancreas, 5.4% (2/37) in the liver, and 3.4% (1/29) in the lung. Seventy-five percent (75%) of ovaries with metastasis were 5 cm or less in the greatest dimension. Seventy-eight percent (78%) of ovarian metastases were bilateral. Fifty-one percent (51%) of the involved ovaries were cystic. Twenty-four percent (24%) of the metastasis were occult in which microscopic disease was present in normal appearing ovaries. The mean age of death in the cases with ovarian metastasis was 53.8 +/- 16.8 years. This was significantly younger than the mean age without ovarian metastasis that mainly was attributable to the younger ages for breast and bile duct cancer. The number of other extraovarian metastatic sites for positive ovarian cases was significantly greater than for the negative ovarian cases (7.6 +/- 2.4 and 5.8 +/- 2.5, respectively). This difference was dominant in gastric and bile duct cancers. The other metastatic sites that accompanied ovarian metastases were the adrenal gland in gastric cancer, the spleen and small intestine in breast cancer, and the adrenal gland and colon in bile duct cancer. The frequency of peritoneal dissemination was essentially the same between cases with positive and negative ovarian metastasis. Scirrhous adenocarcinoma of the stomach more commonly metastasized to the ovary than any other stomach histological type. These findings suggest that although the impact upon outcome of bilateral salpingo-ophorectomy at the initial operation is unknown, the discovery of ovarian metastases in a large proportion of patients may dramatically alter initial management in patients otherwise thought to have only local disease.

Adolescent↗
PubMed1995

Southern blotting analyses of strains of Campylobacter fetus using the conserved region of sapA.

Chromosomal DNA of 27 strains of Campylobacter fetus was analyzed by Southern blotting with a probe of the conserved region of sapA. The probe hybridized with 23 strains that produced type A lipopolysaccharide. These strains had more than six sapA homologs. In Southern blots of SalI-digested chromosomal DNA separated by pulsed-field gel electrophoresis, one fragment from 19 strains and two fragments from 4 strains hybridized. These data indicate that multiple sapA homologs are localized to a limited region on the chromosomal DNA of C. fetus and thus suggest the possibility of developing a typing system using this method.

Bacterial Proteins↗
PubMed1995

Fulminant hepatitis caused by a hepatitis B virus core region variant strain.

We studied the viral genome of a hepatitis B viral strain isolated from a patient with fulminant hepatitis. The patient was followed from prior to the rise in transaminases until she recovered. The precore and core regions of the viral strains were sequenced before and after the illness via the polymerase chain reaction and subcloning methods. Prior to her clinical illness, a strain with precore wild-type sequence and core mutations corresponding to amino acid residues 77 and 113 was noted in large quantities. With the onset of hepatitis, this core variant completely disappeared. Very low titers of precore and core wild or partial core deletion strains remained 1 month later. The core variants described may have contributed to the severe host immune reaction, fulminant hepatitis and immune-mediated viral clearance. Such variants appeared to have been eliminated, and wild and core-deleted virus that lacked the peculiar mutations remained.

Acute Disease↗
PubMed1995

Introduction to the Bioelectronic Devices Project in Japan.

The Bioelectronic Devices Project was organized in Japan as a 10-year national project and it has been working toward developing fundamental key technologies for designing and assembling innovative information-processing devices by realizing the excellent functions specifically found in molecular assemblies and information processing of living organisms. The project is now in the third year of the second phase (the 8th year of its 10-year duration) and researchers have been trying to elucidate the specific characters of the prototype devices. The outline of this challenging project is given with the latest experimental results.

Electron Transport↗
PubMed1995

Transmission of hepatitis C virus from mothers to infants: its frequency and risk factors revisited.

A total of 16,714 pregnant Japanese women were tested for antibodies against hepatitis C virus (HCV), and 163 (0.98%) were positive. None of these were infected with human immunodeficiency virus-1 (HIV-1). We conducted a prospective study to discover the rate of HCV infection in babies born to mothers who were HCV RNA-positive but had no evidence for hepatitis (so called "asymptomatic carriers"), and only 2 (2.3%) of 87 such babies became infected during follow-up. This rate was considerably lower than those from other reports which included mothers with clinically overt chronic hepatitis C. We conducted another study to follow babies born to mothers with chronic hepatitis C, and found two babies infected. All of the four infected babies were born to mothers who had HCV RNA in their circulations around delivery at high titers (greater than 5.0 x 10(6) Eq/ml by branched DNA assay). This confirmed the previous finding that virus load was an important risk factor. In addition, we found three families where mother-to-infant HCV transmission was suspected in a retrospective study by indexing HCV-infected pediatric patients. Throughout the seven families, siblings of infected babies were free from HCV infection, suggesting that maternal infection of HCV owes much to chance. Breast milk feeding was not regarded as a risk factor. We also assessed the prevalence of anti-HCV antibody among 6-year old children, and only 10 of 10,446 (0.1%) were positive, suggesting low frequency of HCV infection during the period from birth to this age.

Carrier State↗
PubMed1995

Three-dimensional ultrastructure of human glomerular basement membrane by a quick-freezing and deep-etching method.

The three-dimensional ultrastructure of glomerular basement membrane (GBM) in surgically resected human kidneys was observed by the quick-freezing and deep-etching method. In three layers of human GBM, the middle layer exhibited polygonal meshwork structures, which were composed of fine fibrils. In addition, the outer and inner layers were formed by lines of perpendicular fibrils, which connected the epithelial or endothelial cell surfaces with the meshwork structures of the middle layer. These ultrastructures might correspond to the three layers, such as lamina densa and laminae rara externa and interna, which were also observed on conventional ultrathin sections. It is concluded that the human GBM has the same meshwork structures and perpendicular fibrils as those previously observed in animals and that these structures may act functionally as size and/or charge barriers.

Adult↗
PubMed1995

Changes in the hepatitis B virus precore and core regions in association with the disappearance of hepatitis B e antigen in patients with chronic hepatitis B.

Disappearance of the hepatitis B e antigen (HBeAg) typically signals the remission of chronic hepatitis B; however, HBeAg defective variants have been identified in patients with HBeAg negative chronic hepatitis (CH). We studied the changes in the hepatitis B virus (HBV) genome associated with HBeAg clearance in four asymptomatic carriers (ASC) and in four patients with CH. Three ASC had a precore stop codon variant with the core region being wild-type or deleted. The other ASC had wild-type precore and core region. In all ASC, HBV levels were reduced markedly with two ASC converting HBV negative status via polymerase chain reaction. In contrast, patients with CH had continued high titers of HBV. In two patients, the precore region remained wild-type, but the core region contained a cleavage site mutation or was deleted. The precore variant was present in both ASC and CH, perhaps suggesting that it does not significantly influence hepatitis B activity.

Adult↗
PubMed1995

[A case of chronic necrotizing pulmonary aspergillosis in which intravenous infusion of amphotericin B was effective].

A 49-year-old man with a history of left upper lung lobectomy for pulmonary asperigilloma developed a productive cough in the middle of April 1992, and his chest X-ray film showed infiltration of the left S6. Treatment with several different antibiotics was tried, but the shadow expanded and developed a cavity over the following 8 months. A clinical diagnosis of chronic necrotizing pulmonary aspergillosis was made, based on repeated detection of Aspergillus fumigatus in the patient's sputum and in specimens obtained by fiberoptic branchoscopy and percuraneous needle biopsy. Prior lobectomy and a marked idiopathic decrease in ventilation and perfusion in the affected lung are risk factors for this disease. Slow intravenous infusion of amphotericin B eradicated the fungus without any side effects. Measurement of drug concentrations during treatment revealed that the concentration in the sputum was far higher than that in the serum, and was also far higher than the minimum inhibitory concentration for the fungus.

Amphotericin B↗
PubMed1995

[Significance of proliferative breast lesions around breast cancers].

To clarify the relationships between benign proliferative diseases and cancers of the breast, 44 cases treated with breast conserving surgeries were analyzed histopathologically. Intraductal hyperplasia, sclerosing adenosis and adenosis were more frequently seen in cancerous than non-cancerous breasts, with a statistically significant difference. Additionally, histologies of some intraductal spread in carcinomas were identical to those of atypical hyperplasias. Further studies should be undertaken, and definitions of atypical hyperplasia, especially in cancerous breasts, should be critically redefined.

Breast↗
PubMed1994

Intraductal carcinoma (ductal carcinoma in situ) of the breast. A comparison of pure noninvasive tumors with those including different proportions of infiltrating carcinoma.

BACKGROUND: Several studies have suggested that ductal carcinoma in situ (DCIS) of the comedo type (variably defined) is biologically more aggressive than other patterns of DCIS and more likely to progress rapidly to invasive carcinoma. METHODS: Eighty-five pure DCISs were compared histopathologically with 64 carcinomas containing both intraductal and infiltrating ductal components (mixed DCIS/IDC). RESULTS: Solid DCIS with and without necrosis was seen more frequently seen in the mixed DCIS/IDC series, especially in cases with less than 50% DCIS. Periductal stromal inflammation and multifocality also were seen more frequently in mixed DCIS/IDC than in pure DCIS. High nuclear grade and high mitotic activity were also more common in the DCIS component of the mixed cases and were well correlated with the intraductal and infiltrating components of the same tumors in most of the cases. The frequency of axillary lymph node metastases was correlated with the proportions of stromal invasion but not with the DCIS subtypes. When the criteria (solid growth pattern, high nuclear grade, and central necrosis) for the diagnosis of intraductal comedocarcinoma were analyzed separately, the first of these correlated most strongly with mixed DCIS/IDC compared with pure DCIS, the second less strongly, and the third not at all, although central necrosis has been considered the main or only diagnostic criterion for comedocarcinoma in several previous reports. CONCLUSIONS: Solid growth pattern and high nuclear grade are the most important histopathologic features of DCIS used to predict progression to invasive carcinoma. No major changes between the intraductal and invasive elements of the same tumors were noted, but other studies have suggested that markers of aggressiveness either increase or decrease in the progression to invasion. These conflicting data require further investigation.

Adult↗
PubMed1994

Archaebacterial lipid models: formation of stable vesicles from single isoprenoid chain-amphiphiles.

Surfactants, PhyN+(Me)3 (OH-/Br-), PhyPO4H- (H+/Na+), PhySO4- (H+/Na+) and Phy(CO2-) (H+/Na+), were prepared; Phy is a (3RS,7R,11R)-3,7,11,15-tetramethylhexadecyl group; phytanic acid or its sodium salt is expressed by Phy(CO2-) (H+/Na+). Equimolecular mixtures of the cationic surfactant and the anionic ones in aqueous media, upon sonication, gave rise to stable suspensions of multilamellar vesicles (MLVs). Unlike the molecular assemblies from cationic and anionic pairs of straight chain-surfactants, the MLVs could trap ionic and nonionic compounds such as 5(6)-carboxyfluorescein and glucose with the captured volume of 0.6-1.6 l/mol in water. The vesicles were tolerant to about 25 mM aqueous NaCl. The packing mode of the surfactants in the membranes are discussed in conjunction with the thickness (about 60 A) and the zeta-potential which was as large as 30-45 mV in water at 20 degrees C.

Archaea↗
PubMed1994

Elevation and clearance of extracellular K+ following graded contusion of the rat spinal cord.

The elevation and clearance of extracellular potassium concentration ([K+]e) were studied following graded contusion injury of the rat thoracic spinal cord. Animals were anesthetized, paralyzed, laminectomized at T9-T10, and then artificially ventilated. A 10-g rod was dropped 1.25, 2.5, or 5 cm onto the dorsal thoracic cord with the dura intact. After impact, and incision of the dura-arachnoid and pial membranes, double-barreled, potassium-selective microelectrodes were inserted midway between the midline and lateral edge of the cord. For all three injury levels, the elevation of [K+]e was greatest within the first 1000 microns from the dorsal surface. In 50 g-cm injuries, increasing [K+]e was sometimes observed between 250 and 1000 microns; however such gradients were not typically observed in 25 and 12.5 g-cm injuries. Measured at 3-7 min after injury, the mean peak elevations of [K+]e were significantly different, measuring 13 +/- 2.4, 27 +/- 5.5, and 44 +/- 4.2 mM following 12.5, 25, and 50 g-cm contusions, respectively. The exponential half-times of [K+]e clearance averaged 5.8 +/- 1.0, 9.2 +/- 1.8, and 17 +/- 5.7 min for the same respective injury levels. These results indicate that elevation of [K+]e following traumatic injury to the spinal cord is a graded phenomenon, dependent on the energy of impact. This finding is consistent with a mechanism in which simple mechanical injury of cell membranes is the proximate cause of potassium release.

Animals↗
PubMed1994

Dynamics of extracellular calcium activity following contusion of the rat spinal cord.

The role of Ca2+ in cellular injury has received particular attention in studies of acute spinal cord trauma. In this context, the spatial and temporal distribution of extracellular Ca2+ ([Ca2+]e) may have an important bearing on the development of secondary tissue injury. We therefore studied the spatial-temporal distribution of [Ca2+]e following moderate (25 g-cm) contusive injury to the rat thoracic (T9-T11) spinal cord. Double-barreled, Ca(2+)-selective microelectrodes were used to measure the magnitude and time course of [Ca2+]e at increasing depths from the dorsal spinal cord surface. After 2 h, the tissue was frozen and later analyzed for total Ca concentration using atomic absorption spectroscopy. [Ca2+]e fell at all depths, but the decrease was maximal at 250 and 500 microns from the dorsal surface, where, at 0-10 min after injury, [Ca2+]e averaged 0.09 +/- 0.03 and 0.06 +/- 0.03 mM respectively. By 2 h postinjury, [Ca2+]e recovered to nearly 1 mM across all depths. Over this time, total tissue calcium concentration ([Ca]t) was 4.54 +/- 0.16 mumol/g in injured cords vs 2.75 +/- 0.1 mumol/g in sham-operated controls. These data place emphasis on the dorsal gray matter as a principal site of ionic derangement in acute spinal cord injury. The implications of these findings are discussed with reference to secondary injury processes.

Animals↗
PubMed1994

Aspartate aminotransferase from a thermophilic formate-utilizing methanogen, Methanobacterium thermoformicicum strain SF-4: relation to serine and phosphoserine aminotransferases, but not to the aspartate aminotransferase family.

The primary structure of the aspartate aminotransferase (AspAT) of an archaebacterium, Methanobacterium thermoformicicum strain SF-4, has been determined by cloning and sequencing of the gene for the enzyme. The gene had a consensus promoter and a ribosome binding sequence of methanogens in the 5' untranslated region, followed by an open reading frame starting with ATG and terminating with TGA. The deduced amino acid sequence was identical with the partial amino acid sequences of the enzyme including the N-terminal sequence, and the deduced molecular weight of 41,684 was virtually identical to that reported earlier for this enzyme [Tanaka, T., Yamamoto, S., Taniguchi, M., Hayashi, H., Kuramitsu, S., Kagamiyama, H., & Oi, S. (1992) J. Biochem. 112, 811-815]. The gene was expressed in Escherichia coli by inserting it into an expression vector just downstream of the lacZ promoter, and this verified that the cloned gene really encodes the Methanobacterium AspAT. The primary structure of the Methanobacterium AspAT showed extremely low homology, 5%, with AspATs of eubacteria, eukaryotes, and a thermoacidophilic arachaebacterium, Sulfolobus solfataricus. On the other hand, the Methanobacterium AspAT showed remarkable amino acid sequence homology, 31.5%, with rat serine:pyruvate aminotransferase and, 13.5%, with E. coli phosphoserine aminotransferase. Thus, the Methanobacterium AspAT apparently belongs to subgroup IV of the aminotransferases [Mehta, P.K., Hale, T.I., & Christen, P. (1993) Eur. J. Biochem. 214, 549-561], but not to subgroup I, in which all the AspATs known so far are included.

Amino Acid Sequence↗