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Biomedical subjects

H Hoshi

Publications and source records attributed to H Hoshi.

At least 19 recordsLinked to original sources
PubMed1999

Multiple chondromatous hamartomas of the lung: a case report and review of the literature with special reference to Carney syndrome.

BACKGROUND: Multiple chondromatous hamartomas of the lung, which are very rare, are a feature of Carney syndrome. The relation between the two entities is not clear. METHODS: A patient with multiple chondromatous hamartomas of the lung is described in this article. The literature was reviewed with special reference to the relation between multiple chondromatous hamartomas of the lung and Carney syndrome as well as the triad of gastric epithelioid leiomyosarcoma, functioning extra-adrenal paraganglioma, and pulmonary chondroma. RESULTS: A total of 15 cases of multiple chondromatous hamartomas of the lung have been published worldwide. Two cases exhibited two other features of Carney syndrome, namely, gastric leiomyogenic neoplasms and extra-adrenal paragangliomas, and three other cases demonstrated only gastric leiomyomatous neoplasms. These five patients were all young females. CONCLUSIONS: Some patients with multiple chondromatous hamartomas of the lung have a history of Carney syndrome. Patients with multiple chondromatous hamartomas require further examination of other sites, particularly the stomach and nervous system.

Chondromatosis↗
PubMed1999

Ultrastructure of bovine embryos developed from in vitro-matured and -fertilized oocytes: comparative morphological evaluation of embryos cultured either in serum-free medium or in serum-supplemented medium.

The ultrastructure of bovine embryos developed from in vitro-matured and -fertilized oocytes, cocultured with bovine cumulus/granulosa cells either in a serum-free medium (IVMD101) or in a serum-containing medium (TCM199+CS) was compared. Embryos up to the eight-cell stage had many cellular organelles and cytoplasmic components that were randomly distributed in the cytoplasm. Mitochondria were spherical or ovoid and had only a few peripheral cristae. There were no obvious differences in the ultrastructure between embryos developed in IVMD101 and TCM199+CS up to the eight-cell stage. However, conspicuous differences in the ultrastructural features between the embryos cultured in IVMD101 and TCM199+CS were observed at the morula and blastocyst stages. At the morula stage, embryos cultured in IVMD101 had cells containing elongated mitochondria, well-developed Golgi apparatus, lipid droplets, and large vesicles resembling lysosomes. The lysosome-like vesicles were partially filled with electron-dense materials and were frequently fused with lipid droplets. The blastomeres of morulae cultured in TCM199+CS contained numerous large lipid droplets and fewer lysosome-like vesicles than those cultured in IVMD101. In blastocysts cultured in IVMD101, lysosome-like vesicles were frequently observed in the trophoblast cells and lipid droplets were present in the cytoplasm of trophoblast and inner cell mass (ICM)-cells, but they were not abundant. On the other hand, the blastocysts developed in TCM199+CS contained fewer lysosome-like vesicles and large numbers of lipid droplets. This accumulation of lipid droplets was higher in the trophoblast cells than in the ICM-cells. This study showed major differences in the ultrastructural features between the morulae and blastocysts from serum-free and serum-supplemented cultures, suggesting that the ultrastructural differences may reflect physiological characteristics of embryos.

Animals↗
PubMed1999

Fat-suppressed T2-weighted MR imaging of hepatocellular carcinoma and metastases: comparison of conventional spin-echo, fast spin-echo, and echoplanar pulse sequences.

The purpose of our study was to compare the diagnostic accuracy of fat-suppressed T2-weighted magnetic resonance (MR) images obtained with conventional spin-echo (SE), respiratory-triggered fast SE, and breath-hold multishot SE echoplanar (EP) sequences for the detection of hepatocellular carcinoma and metastases. Images obtained with the three sequences in 17 patients (15 with cirrhosis) with 31 hepatocellular carcinomas and 14 patients with 45 metastases were retrospectively analyzed. Image review was conducted on a segment-by-segment basis; in all, 248 liver segments were reviewed separately and independently for detection of solid, malignant lesions. Diagnostic accuracy was evaluated with receiver-operating-characteristic (ROC) curve analysis. Diagnostic accuracy for hepatocellular carcinoma as determined by ROC curve analysis was better by a statistically significant amount for conventional SE (Az = 0.95) images when compared with respiratory-triggered fast SE (Az = 0.83, P < 0.05) and breath-hold multishot SE EP (Az = 0.80, P < 0.05) images. Conventional SE MR sequences should not be replaced with respiratory-triggered fast SE or breath-hold multishot SE EP sequences for T2-weighted MR imaging of patients with hepatocellular carcinoma in cirrhosis, unless sufficient contrast-enhanced dynamic MR imaging is subsequently performed.

Adult↗
PubMed1999

Fine structure of bovine morulae and blastocysts in vivo and in vitro.

The ultrastructure of bovine morulae and blastocysts developed from in vitro-matured and -fertilized oocytes in a serum-supplemented medium was compared with that of morulae and blastocysts collected non-surgically from superovulated cows. In the in vivo-derived morulae, two characteristic cells types could be identified by the electron-density of their cytoplasm and by their ultrastructural features. One type appeared light in color with low electron-dense cytoplasm. These cells were located in the peripheral layer of the cluster of blastomeres, possessed numerous cellular organelles such as mitochondria and Golgi apparatus and had microvilli projecting into the perivitelline space. The other cell type was distinguished by cytoplasm that stained more densely than that of the lighter-appearing cells. The darker-appearing cells generally possessed fewer organelles than the lighter cells, but many lysosome-like structures were present in the cytoplasm. The in vitro-developed morulae also contained two types of cells similar to those observed in the in vivo morulae. However, most of the in vitro-developed cells possessed numerous lipid droplets and contained fewer lysosome-like structures than the cells of the in vivo-derived morulae. The blastocysts, both in vivo and in vitro, showed a clear differentiation of trophoblast cells and inner cell mass (ICM)-cells. In the in vivo-derived blastocyst, the apical membrane of trophoblast cells was covered with large, numerous microvilli and well-developed junctional complexes were observed. Lipid droplets were present in the cytoplasm of trophoblast and ICM-cells but were not abundant. In vitro-developed blastocysts showed less well-developed junctional complexes between trophoblast cells, less well-developed apical microvilli on the trophoblast cells, and contained large numbers of lipid droplets. This accumulation of lipid droplets was higher in the trophoblast cells than in the ICM-cells. The zonae pellucidae of in vitro-developed embryos were thinner than that of the in vivo-derived embryos. This study demonstrates conspicuous differences in the ultrastructural features between the in vivo-derived and in vitro-developed embryos, suggesting that the ultrastructure may reflect the various physiological anomalies observed in previous studies.

Animals↗
PubMed1999

Bone marrow stroma from refractory anemia of myelodysplastic syndrome is defective in its ability to support normal CD34-positive cell proliferation and differentiation in vitro.

We examined the supportive function of stromal cells from patients with refractory anemia (RA) of myelodysplastic syndrome (MDS) on CD34-positive hematopoietic cell proliferation and differentiation using a long-term bone marrow culture (LTMC) system. Primary marrow stromal cells were obtained from 11 MDS RA patients and 12 healthy volunteers, and freshly prepared CD34-positive bone marrow cells from a normal subject were inoculated onto the stroma. There seems to be three broad patterns of hematopoietic cell growth in the LTMCs. In one group, hematopoietic cells were maintained at near normal levels (type A). In the second group, the number of hematopoietic cells increased within the first 5-10 days of culture, but declined to low levels at 15-20 days of culture as compared with normal control (type B). In the third group, the incidence of hematopoietic cells steadily declined from the beginning of the culture (type C). Furthermore, apoptotic change of hematopoietic cells was very frequently observed in cultures with the type C stroma, which were especially defective for supporting CD34 + cell proliferation and differentiation. The expression of CD95 on hematopoietic cells was induced by the type C stroma, however, production of fas ligand by the stromal cells was not observed. These findings suggest a lack of hematopoietic supportive function in some cases of MDS RA and also indicate that there is heterogeneity of stromal function among MDS RA patients.

Adult↗
PubMed1999

Multiglycosidorum tripterygii, a new immunosuppressant, supresses coronary arteriosclerosis after heart transplantation.

BACKGROUND: Graft coronary arteriosclerosis is the major limiting factor for long-term survival after heart transplantation. In this study, we investigate the effect of multiglycosidorum tripterygii on graft coronary arteriosclerosis and platelet-derived growth factor A mRNA expression of transplanted hearts. METHODS: Three groups of Lewis rats (n = 7/Group) underwent heterotopic heart transplantation from Wistar-King donors and were treated with cyclosporine A (10 mg/ kg/day) for 60 days (Group A) or with multiglycosidorum tripterygii (30 mg/kg/day) for 60 days (Group B) or with cyclosporine A for the first 30 days and followed by multiglycosidorum tripterygii for another 30 days (Group C). Histological evaluations of rejection and coronary arteriosclerosis, as well as Northern blot analysis on graft platelet-derived growth factor A mRNA expression were made 60 days after transplantation. RESULTS: Morphometric results indicated no significant difference in rejection among three groups. However, the extent of graft coronary arteriosclerosis in Group B (1.12 +/- 0.21) and Group C (1.41 +/- 0.19) was significantly less than that seen in Group A (1.72 +/- 0.18) (p < 0.01 andp < 0.05, respectively). Furthermore, the incidence of diseased vessels was significantly less in Group B (29.5% +/- 7.8%) and Group C (42% +/- 9.1%) compared with Group A (69.1% +/- 11%) (p < 0.01 and p < 0.05, respectively). The expression of platelet-derived growth factor A mRNA of cardiac allograft was also significantly suppressed in Group B (25.4 +/- 6.2) and Group C (39.8 +/- 9.4), when compared with Group A (62.2 +/- 12.9) (p < 0.01 and p < 0.05, respectively). CONCLUSION: Multiglycosidorum tripterygii is superior to cyclosporine in prevention and attenuation of graft coronary arteriosclerosis and this efficacy is probably associated with the depressed expression of graft platelet-derived growth factor A mRNA in the multiglycosidorum tripterygii-treated groups.

Animals↗
PubMed1999

Potential utility of magnetic resonance cholangiography in the management of endoscopic biliary drainage tubes.

An 80-yr-old woman with advanced hilar cholangiocarcinoma underwent a placement of endoscopic biliary drainage (EBD) tube from the common hepatic to common bile duct through the stricture. Magnetic resonance cholangiography clearly demonstrated the later dislocation and obstruction of the EBD tube. The present case suggests that magnetic resonance cholangiography may be a potentially useful tool in the management of EBD tubes.

Aged↗
PubMed1999

Focal hepatic lesion detection: comparison of four fat-suppressed T2-weighted MR imaging pulse sequences.

PURPOSE: To evaluate fat-suppressed T2-weighted magnetic resonance (MR) imaging with conventional spin-echo (SE), breath-hold fast SE, respiratory-triggered fast SE, and breath-hold multishot SE echo-planar sequences for the detection of focal hepatic lesions. MATERIALS AND METHODS: Fat-suppressed T2-weighted MR images obtained with the four sequences in 55 patients with 81 solid and 129 nonsolid lesions were retrospectively analyzed. Image review was conducted on a segment-by-segment basis; a total of 440 liver segments were reviewed separately for solid and nonsolid lesions by three independent radiologists. Diagnostic accuracy was evaluated with receiver operating characteristic analysis. RESULTS: The mean lesion-to-liver contrast-to-noise ratio was highest on the multishot SE echo-planar images of both solid and nonsolid lesions. Fat-suppressed respiratory-triggered fast SE images had significantly better (P < .05) or comparative detectability of both solid and nonsolid lesions compared with the other types of images. Image quality was best on the respiratory-triggered fast SE images. CONCLUSION: Fat-suppressed respiratory-triggered fast SE imaging should replace fat-suppressed conventional SE imaging as a standard T2-weighted imaging examination in the detection of focal hepatic lesions.

Adipose Tissue↗
PubMed1999

Influence of carbon dioxide on respiratory function during posterior retroperitoneoscopic adrenalectomy in prone position.

OBJECTIVE: To evaluate the influences of CO(2) insufflation on changes in blood gas analysis and end tidal CO(2) tension (PetCO(2)) during posterior retroperitoneoscopic adrenalectomy in the prone position. METHODS: Arterial blood gas analysis and measurements of PetCO(2) were carried out during CO(2) insufflation in 16 patients who underwent posterior retroperitoneoscopic adrenalectomy in the prone position (PRA group). The results were compared to 10 patients who underwent open posterior adrenalectomy (OPA group). Ventilation was artificially controlled during the study period in all cases. RESULTS: Arterial pH, PaCO(2), PetCO(2) and PaO(2) were not significantly different between the PRA and OPA groups. However, the PaCO(2)-PetCO(2) gradient in the PRA group was significantly higher than that in the OPA group (p < 0.01). CONCLUSION: Transperitoneal absorption of CO(2) occurs in patients undergoing retroperitoneoscopy in the prone position. The alveolo-arterial CO(2) gradient may be the only parameter which indicates the absorption of CO(2) during PRA.

Adrenal Gland Neoplasms↗
PubMed1999

Effects of immunosuppressants on platelet-derived growth factor-A chain mRNA expression and coronary arteriosclerosis in rat cardiac allografts.

Graft coronary arteriosclerosis (GCA) that results in proliferative and obstructive lesions limits the long-term success of cardiac transplantation. Despite extensive study, the pathogenic mechanisms underlying GCA are still unclear and therapeutic strategies for this condition have been inadequate. In this study, we compared the therapeutic effectiveness of cyclosporine A (CsA), 15-deoxyspergualin (DSG), and Multiglycosidorum tripterygii (MT) on GCA. In addition, we studied the correlation between the extent of GCA and the degree of platelet-derived growth facter (PDGF)-A chain mRNA expression in cardiac grafts. Lewis rats receiving heterotropic heart transplants from Wistar King donors were treated with 10 mg kg(-1) day(-1) of CsA (n=7), 5 mg kg(-1) day(-1) of DSG (n=7) or 30 mg kg(-1) day(-1) of MT (n=7) respectively. Histological evaluation of coronary arteriosclerosis and Northern blot analysis of cardiac allograft PDGF-A chain mRNA expression were conducted on day 60 after transplantation. Varying levels of GCA were observed in the 21 transplanted hearts. Significant differences in both the degree of PDGF-A mRNA expression and the extent of GCA were found among the 3 groups. GCA was significantly reduced in allografts treated with MT or DSG in comparison with the level seen in CsA-treated grafts. A significant correlation was found between PDGF-A chain mRNA expression and the grade of arterial intimal thickening (r=0.76, p<0.05) as well as with the incidence of diseased vessels (r=0.82, p<0.01). Our results indicate that both MT and DSG are more effective in the treatment of GCA than CsA. In our cardiac allografts, the degree of PDGF-A chain mRNA expression correlated well with the extent of GCA, suggesting that PDGF-A may play an important role in the development of transplant-related GCA.

Animals↗
PubMed1999

Development of Babesia gibsoni in the midgut of larval tick, Rhipicephalus sanguineus.

Studies were made on the development of Babesia gibsoni in the midgut of the larval tick, Rhipicephalus sanguineus. Six hr after repletion, merozoites of B. gibsoni, freed from erythrocytes, were observed in the midgut contents of the tick. After that, within 24 hr, those merozoites were transformed into the ring-forms which were relatively large, 2-3 microns in diameter. Later, the ring forms developed into the spherical forms which were subelliptical in shape and 4-6 microns in diameter. Within 2-4 days, the elongated forms, 5-8 microns in length, were found. At this time, some of the binucleated fusion form has assumed a form intermediate between the spherical and elongated-forms. About 5-6 days after repletion, large round or elliptic zygotes, 8-10 microns in diameter, were observed in the tick gut.

Animals↗
PubMed1999

Development of Babesia gibsoni in the midgut of the nymphal stage of the tick, Rhipicephalus sanguineus.

Studies were made on the development of Babesia gibsoni in the midgut of the nymphal stage of the tick, Rhipicephalus sanguineus. Six hr after repletion, merozoites of B. gibsoni, free of erythrocytes, were observed in the midgut contents of the ticks. After that, within 24 hr, those merozoites were transformed into ring-forms which were relatively large ring 1-2 microns in diameter. Later, the ring forms developed into spherical forms which were somewhat elliptical in shape and 3-4 microns in diameter. Within 2-4 days, bizarre forms (5-6 microns in diameter) developed into elongated forms (5-6 microns in length). About 5-6 days after repletion, large round or elliptic zygotes (7-9 microns in diameter) were observed in the ticks gut.

Animals↗
PubMed1999

Development of immune complex trapping: experimental study of lymphoid follicles and germinal centers newly induced by exogenous stimulants in mouse popliteal lymph nodes.

The development of immune complex trapping in newly-induced lymphoid follicles of draining popliteal lymph nodes was investigated in young adult mice, which had been given bilateral injection of hemocyanin (KLH) or phytohemagglutinin (PHA), each absorbed onto alumina. HRP-anti-HRP immune complex was injected into the footpad 1 day before sacrifice. Using three series of semi-serial cryostat sections prepared from each popliteal node, the number of lymphoid follicles in each node was counted, and follicular localization of the in vivo injected and in vitro applied immune complexes in each follicle was determined. By day 5, a large germinal center had developed within each preexisting follicle. A large number of 'new' secondary follicles, each containing a small PNA-positive germinal center, appeared outside pre-existing follicles, from day 5 through day 11 in KLH-treated nodes, and from day 7 through day 14 in PHA-treated nodes. Shortly after their appearance, new secondary follicles showed no in vitro or in vivo trapping, but subsequently, many of the new follicles began to display in vitro trapping, at first weakly but later intensely. Occurrence of in vivo trapping in new follicles took some time and was first recognized when new follicles showed intense in vitro trapping. At day 21 or 25, many of the new follicles showed both in vitro and in vivo trapping. It was concluded that in lymph nodes treated with a stimulant, secondary follicles containing germinal centers can be formed de novo in the extrafollicular zone where the follicular trapping microenvironment is absent, but subsequently the microenvironment capable of trapping immune complexes develops at the site of formation of new follicles.

Alum Compounds↗