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Biomedical subjects

H Shirasawa

Publications and source records attributed to H Shirasawa.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Diagnosis of precancerous lesions of the endometrium].

Cytodiagnosis of the precancerous lesions of the endometrium has remained unclear compared to that for cervical lesions. Endometrial cytology and biopsy have been performed for patients with atypical genital bleeding, who were over fifty, postmenopausal or nulliparous, We studied cytologic findings in cystic glandular, adenomatous and atypical hyperplasia, and compared to them in early cancer. Differential diagnosis was somewhat difficult between cystic glandular hyperplasia and benign lesions. Cytological diagnosis becomes gradually easier with progress of the lesions. A few cases with endometrial hyperplasia developed endometrial carcinoma for several years. Endometrial carcinoma has been detected even in the patients with suspicious endometrial cytology, so endometrial biopsy is still an important method. However, endometrial cytology is very easy, so we need to clarify the cytological cytological characteristics in precancerous lesions of the endometrium.

Cytodiagnosis↗
PubMed1988

C1q production and C1q-mediated immune complex retention in lymphoid follicles of rat spleen.

Involvement of C1q in retaining immune complexes in germinal centers in rat spleen was studied in vivo and in vitro. C1q production was found in fibroblastic reticulum cells in the peripheral mantle zone, in follicular dendritic cells in germinal centers, and in transitional forms between these two cells in the inner mantle zone. In passively immunized animals, immune complexes were found transiently on fibroblastic reticulum cells, then on the transitional forms and follicular dendritic cells. Extracellular C1q was detected by the presence of immune complexes on both the transitional forms and follicular dendritic cells, but not on fibroblastic reticulum cells. Thus, the fibroblastic reticulum cell appeared to trap immune complexes but not to retain either immune complexes or C1q. The morphology and function of the fibroblastic reticulum cell and the follicular dendritic cell suggest that they belong to the same lineage. Immune complexes were bound in vitro to germinal centers in cryostat spleen sections in the same manner as those retained in vivo. The binding required no complement in the incubation medium and was inhibited by C1q-suppressing factors. The extracellular C1q originating from the follicular cells may therefore play a role in retaining immune complexes in the germinal center.

Animals↗
PubMed1988

Primary carcinoid tumor of the liver.

A primary hepatic tumor with histologic features suggestive of carcinoid tumor is reported, and six previously reported cases reviewed. Tumor cells contained electron dense secretory granules with an average diameter 150-200 nm which demonstrated positive argyrophilic reactions. On immunohistochemistry, chromogranin A was positively stained. No endocrine syndrome was present and an alternative primary source of the tumor was not found, despite an intensive search.

Adult↗
PubMed1988

Localization of Fc receptors on liver sinusoidal endothelium. A histological study by electron microscopy.

The localization of Fc receptors for IgG on mouse liver sinusoidal endothelium was studied in tissue sections by light and electron microscopy using peroxidase-antiperoxidase IgG complexes as ligands. Light microscopy revealed that Fc receptors were continuously present along the sinusoidal wall, but absent on the endothelium of the central vein and that of the portal area blood vessels. Electron microscopy revealed Fc receptors on both the luminal and basal aspects of the plasma membrane, far more being present on the former, on the walls of cytoplasmic fenestrae, and abundantly on the walls of coated pits and vesicles of sinusoidal endothelial cells. Fc receptors were found more frequently on sinusoidal endothelial cells than on Kupffer cells. Fat-storing cells lacked the receptors and hepatocytes showed an ambiguous result which was considered to be nonspecific.

Animals↗
PubMed1988

Transcriptional differences of the human papillomavirus type 16 genome between precancerous lesions and invasive carcinomas.

Human papillomavirus type 16 (HPV16) genome DNA and its transcripts in biopsied cervical neoplasias were analyzed by simultaneous extraction of DNA and RNA from one biopsied sample. Southern blot analysis revealed that 5 of 20 cervical intraepithelial neoplasias (CINs) contained HPV16 DNAs existing primarily as episomes and two of seven invasive carcinomas harbored HPV16 genome sequences integrated into the host DNA. Northern (RNA) blot analysis showed that the HPV16 genome sequences were transcriptionally active in the five CINs, as well as in the two invasive carcinomas. The pattern of HPV16-specific transcripts in the CINs was uniform, and the major transcripts were 4.2, 2.2, 1.6, and 1.4 kilobases in size. However, the pattern of HPV16-specific transcripts in the invasive carcinomas was variable and different from that in CINs, suggesting that the alteration of transcriptional pattern might play a key role in the development of malignancy.

Carcinoma↗
PubMed1987

Fc receptors of liver sinusoidal endothelium in normal rats and humans. A histologic study with soluble immune complexes.

Fc receptors for immunoglobulin G in the liver sinusoidal wall were studied in the normal rat and in humans by applying peroxidase-antiperoxidase immunoglobulin G complexes to the frozen sections. Fc receptors were found to exist continuously along the sinusoidal lining. The receptors showed no zonal distribution in the rat, and they were generally scarce near the central veins and portal areas in humans. To characterize the sinusoidal cells, carbon or latex was given intravenously and endogenous peroxidase was demonstrated for the rat, whereas factor VIII-related antigen and endogenous peroxidase were demonstrated for the humans. In the rat, Fc receptors were detected on Kupffer cells, which were characterized by an intense endogenous peroxidase activity and ingestion of latex or quantities of carbon. They were also detected on sinusoidal endothelial cells, which were characterized by undetectable peroxidase activity and no ingestion of latex nor of a small quantity of carbon. In humans, Fc receptors were also present on Kupffer cells as well as sinusoidal endothelial cells, as identified by endogenous peroxidase and factor VIII-related antigen, respectively.

Animals↗
PubMed1987

Expression of the human papillomavirus type 6b L2 open reading frame in Escherichia coli: L2-beta-galactosidase fusion proteins and their antigenic properties.

Human papillomavirus (HPV) type 6b genome contains two large open reading frames (ORFs), designated L1 and L2, in a putative late region. These ORFs are expected to code for viral structural proteins. To examine antigenic properties of a L2 gene product, we constructed two plasmids which contain N-terminal (L2-N) and internal (L2-I) regions of the HPV6b L2 ORF and then each region was expressed in Escherichia coli as a fusion protein with E. coli beta-galactosidase (beta-Gal). Both L2-N/beta-Gal fusion proteins reacted with anti-beta-Gal antibody, but did not react with the antibody prepared against bovine papillomavirus type 1 (BPV1), in contrast with a high reactivity of HPV6b L1-beta-Gal fusion protein with the anti-BPV1 antibody. Antibody raised against the L2-I/beta-Gal protein in a rabbit reacted with viral antigens in the nuclei of cells in superficial epithelium of the condyloma acuminatum tissue, but did not react with the antigens in the bovine papilloma tissue. This antibody recognized a protein from condyloma acuminata which migrates to the position of mol wt 70K-76K on an electrophoresed SDS-polyacrylamide gel. These results suggested that the L2 ORF of HPV6b codes for a capsid protein which is less cross-reactive than the L1 antigen with anti-BPV1 antibody.

Antibodies, Viral↗
PubMed1987

Integration and transcription of human papillomavirus type 16 and 18 sequences in cell lines derived from cervical carcinomas.

Five cell lines, SKG-I, SKG-II, SKG-IIIb, QG-U and QG-H derived from cervical carcinomas of Japanese patients, were examined for the presence of human papillomavirus (HPV) DNA and the expression of viral mRNA. The DNA of HPV type 16 was shown to be linked covalently with SKG-IIb, QG-U and QG-H cell DNA, and HPV 18 DNA with SKG-I and SKG-II cell DNA. Although different regions of the HPV genome were integrated in these cell lines, the non-coding region and an early region including the E6 and E7 open reading frames (ORFs) were conserved in all cell lines. The complete genome of HPV 16 was found in QG-H cells by digestion of the DNA with a single-cut restriction enzyme. The other early region ORFs E1, E2, E4 and E5 were interrupted by flanking host cell DNA, suggesting that the integration into host cell DNA occurs preferentially in this region. HPV-specific mRNA species were detected in all five cell lines. In the three cell lines containing the HPV 16 genome, mRNAs hybridized with the early region of the genome, covering the entire E6 and E7 ORFs and a minor part of the E1 ORF, although the amount and size of the major mRNAs varied in these cell lines. These mRNAs did not hybridize with the late region of the HPV genome containing the L1 and L2 ORFs. In SKG-II, SKG-IIIb and QG-H cells we also detected c-myc and c-Ha-ras mRNA expression at about nine times the level of that in normal cells.

Base Sequence↗
PubMed1987

Congenital muscular dystrophy of the Fukuyama type (FCMD) with severe myocardial fibrosis. A case report with postmortem angiography.

Autopsy findings of a 17-year-old Japanese male with the typical features of congenital muscular dystrophy of the Fukuyama type (FCMD) are presented. This case showed progressive muscular dystrophy and central nervous system malformation, accompanied by severe myocardial fibrosis. Large mitochondrial dense bodies were found in both the cardiac and skeletal muscle cells. Postmortem coronary angiography failed to reveal the presence of any obstructive lesions responsible for myocardial fibrosis. It was also demonstrated that abnormal vessels proliferating in an area of micropolygyria (MPG) in the cerebrum were branches of the cortical artery originating from the pia mater. The cerebral malformation was accompanied by basal skull deformities.

Adolescent↗
PubMed1987

Expression of human papillomavirus types 6b and 16 L1 open reading frames in Escherichia coli: detection of a 56,000-dalton polypeptide containing genus-specific (common) antigens.

The human papillomavirus (HPV) genome contains two large open reading frames (ORFs), designated L1 and L2. To characterize the antigenic properties of the L1 ORF-encoded proteins, we cloned the L1 ORFs of HPV6b and HPV16 in plasmids, and these were expressed in Escherichia coli. First, the HPV6b DNA, representing 85.2% of the L1 ORF, was cloned in pUC19 and expressed in E. coli JM83 and RB791 as a 160,000-molecular-weight (160K) fusion protein with E. coli beta-galactosidase (6bL1/beta-gal). Second, the HPV16 DNA, representing 89.8% of the L1 ORF, was cloned in pKK233-2 and expressed as a 56K protein (16L1) in strain RB791. Both the 6bL1/beta-gal and 16L1 proteins cross-reacted with anti-bovine papillomavirus type 1 (BPV1) antibody raised against disrupted BPV1 particles. An antibody raised against the 6bL1/beta-gal fusion protein reacted with the 16L1 protein and also with native papillomavirus antigens in human genital condyloma and bovine fibropapilloma tissues, as determined by biotin-streptavidin staining. Furthermore, the anti-6bL1/beta-gal antibody recognized a 54K protein which seemed to be a major capsid protein of BPV1 and also a 56K protein of biopsies harboring HPV6 or HPV11. From these results we concluded that the papillomavirus L1 gene product contains genus-specific (common) antigens and that the HPV6 and HPV11 L1 genes specify the 56K capsid protein.

Animals↗
PubMed1986

Effects of L-carnitine and verapamil on myocardial carnitine concentration and histopathology of Syrian hamster BIO 14.6.

In order to investigate the effects of L-carnitine and verapamil on myocardial carnitine metabolism carnitine derivatives were measured and histopathology studied in the BIO 14.6 Syrian hamster. Cardiomyopathic hamsters at 20 days of life were divided into three groups, each given saline solution, L-carnitine, or verapamil. At 90 days of life the myocardial tissue concentrations of free carnitine, short chain acylcarnitine, and total carnitine in Syrian hamsters were significantly lower than those in normal hamsters of the same age. The myocardial tissue concentrations of free carnitine, short chain acylcarnitine, and total carnitine were significantly higher in the L-carnitine group than in the saline group, and the concentrations of free carnitine and total carnitine were significantly higher in the verapamil group than in the saline group. The percentage area of necrosis, fibrosis, and calcification in the L-carnitine and verapamil groups was significantly smaller than that in the saline group. These results suggest that lowered carnitine concentrations in the myocardium might play an important pathophysiological role in the genesis of the BIO 14.6 cardiomyopathic Syrian hamster and that L-carnitine and verapamil might be beneficial in the treatment of cardiomyopathic hamsters.

Animals↗
PubMed1986

Detection of human papillomavirus type 16 DNA and evidence for integration into the cell DNA in cervical dysplasia.

The presence of human papillomavirus (HPV) type 16 DNA in biopsies from precancerous lesions and from early lesions of human cervical cancer, and the integration of virus DNA into host cell DNA were analysed by dot blot and Southern blot hybridizations. HPV 16 DNA was detected in 23% of mild dysplasias, 32% of moderate dysplasias, 55% of severe dysplasias and 62% of carcinomas in situ by dot blot hybridization. Digestion of the DNA with restriction enzymes PstI and BamHI followed by Southern blot analysis revealed the presence of some typical restriction fragments of HPV 16 DNA in most virus-positive samples. In addition, we detected submolar fragments which might represent virus-cell junction sequences in 86% of dysplasias, suggesting that the integration of HPV 16 DNA could occur in the precancerous stage.

Carcinoma in Situ↗
PubMed1986

Glomerular injury in mice induced by Agkistrodon venom.

Glomerular injury was produced in mice after a single LD50 intravenous dose of purified 100-pace snake venom (Agkistrodon acutus). Characteristic features in glomeruli where the venom was demonstrated immunohistochemically included cystic lesions of the capillary tufts, thrombosis, subsequent proliferative and sclerotic changes, and crescent formation. Venom was recognized immunohistochemically in the glomerular endothelium, visceral basement membrane, mesangium, epithelium, and Bowman's capsule. Venom transfer across the basement membrane or into cells required less than 2 hours. Within this period mesangiolysis occurred due to the protease activity of the venom. Cystic lesions with fibrin thrombi then developed, which were replaced by proliferative and sclerotic changes after 3 days. Crescent formation began within 48 hours and was completed within a few days. Microangiography revealed hemodynamic changes in the intrarenal vasculature after venom treatment. Immune complex deposition was not found in any tissue. The study demonstrates the moderately constant potency (LD50) of Agkistron acutus venom, and documents it as a useful tool for quantitative studies of renal lesions.

Angiography↗
PubMed1986

[A case of malignant epithelioid schwannoma in the triceps muscle of the arm].

A patient with malignant epithelioid schwannoma in the right triceps muscle of the arm is reported. This tumor was mainly composed of plump epithelioid cells, which showed focal necrosis and nuclear arrangement in palisades. The structures and the presence of long cytoplasmic processes, discrete basal lamina, and long spaced collagen on electron microscopic examination suggested schwannian derivation of the tumor. The tumor exhibited metastasis to the axillary lymph nodes. However, no recurrence was observed a year after surgical removal, irradiation, and chemotherapy.

Adult↗
PubMed1985

Carnitine derivatives in hereditary cardiomyopathic animals.

BIO 14.6 Syrian hamsters and diabetic KK mice have been reported to develop hereditary cardiomyopathy spontaneously. In order to investigate the pathophysiological role of carnitine metabolism in hereditary cardiomyopathy, tissue levels of carnitine derivatives and the histology of the heart, liver and skeletal muscles from BIO 14.6 hamsters and KK mice were studied. Free carnitine levels in the heart of the BIO 14.6 hamsters (287.0 +/- 27.0 n mole/g wet tissue) were significantly lower than in the control group (348.8 +/- 83.8, p less than 0.05). Short chain acylcarnitine (197.0 +/- 56.0 n mole/g wet tissue) and total carnitine (667.6 +/- 136.4 n mole/g wet tissue) in the hearts of the BIO 14.6 hamsters were significantly lower than in the control group (short: 425.2 +/- 54.8, total: 1023.6 +/- 81.4, p less than 0.001). There was no significant difference in the levels of various carnitine derivatives of the liver and skeletal muscles from the BIO 14.6 hamsters and control hamsters. On the other hand, carnitine derivatives in KK mice did not change significantly compared with those in the heart, liver and skeletal muscles of the control mice. Histological findings showed that heart muscle degeneration and necrosis were found in both cardiomyopathic animals. Coagulative necrosis was found in both animals, whereas myocytolytic necrosis was found only in the BIO 14.6 hamsters. In KK mice, the right ventricle, especially tissue under the epicardium, was severely affected compared with the left ventricle. In the BIO 14.6 hamsters, however, lesions were scattered over both ventricles with a predilection for the left ventricle.

Animals↗
PubMed1985

Immunohistochemical detection of serum amyloid A protein in the liver and the kidney after casein injection.

Localization of serum amyloid A protein (SAA) was observed by direct peroxidase-labeled antibody method. SAA was induced in mice by a single subcutaneous injection of casein. Before injection, trace amounts of SAA were detected in a few hepatocytes around the central vein. From 3 to 24 hours after injection, the area of SAA-positive hepatocytes extended to the midlobular zone and then gradually decreased in size. On electron microscopy, SAA was present in rough endoplasmic reticulum, smooth endoplasmic reticulum, lipid droplets, and vesicles containing lipid particles. Some lipid particles were positively stained in the space of Disse. From 6 to 36 hours after injection, SAA appeared in the proximal convoluted tubules of the kidney, where SAA was associated with fine particles at the brush border and with multivesicular bodies and lipid droplets in the cytoplasm. Between 18 and 24 hours after injection, SAA appeared in periportal to midlobular hepatocytes as granular deposits. SAA was localized in the cytoplasm around lipid droplets and small vesicles. These vesicles were recognized as endocytic vesicles by their localization close to or fused with peroxisomes and lysosomes. In the kidney SAA was distributed in mesangial cells, podocytes, and tubular interstitium. Localization of SAA in amyloid-laden mice that had received 30 casein injections was almost the same as that in ones that had received a single injection, i.e., hepatocytes, proximal convoluted tubules, and glomeruli. Amyloid deposition was detected near or at the same sites as those where SAA later appeared. Based upon these results we postulate that: Hepatocytes participate in not only the production, but also in the degradation of SAA. At least part of SAA is secreted as a lipid combined form. Circulating SAA is filtered through the glomeruli into Bowman's space and reabsorbed from the proximal convoluted tubules. SAA is metabolized at the same sites even in the amyloid laden state and amyloid is deposited in close relation to the catabolic pathway of SAA.

Amyloid↗