Biomedical subjects

E Sato

Publications and source records attributed to E Sato.

At least 235 records · Page 13Linked to original sources

PubMed1996

Application of sweet potato fiber to skin wound in rat.

In order to introduce a suitable drug mixing base or covering for burns or decubital wounds, the usefulness of fiber extracted from the sweet potato was investigated. The healing effect of the fiber was evaluated by examining the extent of reduction in the size of wounds and changes in the quality of wounds in rats. In contrast to the control, the use of the fiber alone as a wound covering material reduced wounded areas by 21.0% at postoperative day 9, 19.5% at day 11, and 18.7% at day 13, and resulted in an obvious increase in the rats' weight. The number of days required for healing in all treated rats was 19 for the fiber groups and over 21 d for the control. In vitro, the fiber indicated excellent absorptive ability for serum and good adhesive ability for a number of proteins. This result suggested that the fiber has favorable properties for healing wounds which contain large amounts of exudate. Our macroscopic findings also indicated that the fiber protected wounds from dryness. These results suggested that sweet potato fiber could be use as a covering material in combination with drugs in skin wound therapy.

Absorption↗

PubMed1996

Magnetic resonance imaging of the internal structure of the mouse fetus.

Magnetic resonance imaging (MRI) has potential as an imaging technique in fetal anatomy. In this article are presented images obtained from mouse fetuses at 16 days of pregnancy by means of the ultraconductive MRI system (JEOL AIM270). When fetuses removed from the uterus were fixed with 10% neutral formalin, various organs including heart, liver, lungs and bones were clearly seen, and a clear outline was obtained of the fetal skin and subcutaneous tissue by varying the setting. The same specimens were able to be used for histological evaluation. This MRI system will allow wider application in fetal anatomy and provide additional information about the developing mouse fetus.

Abdomen↗

PubMed1995

Tissue-specific regulation of the expression of rat intestinal bile acid-binding protein.

A lipid-binding protein identical to the rat intestinal bile acid-binding protein, termed I-15P, was expressed in steroid hormone-producing tissues such as ovary and adrenal gland, but not testis. In immature rats, I-15P was expressed in intestine but not in ovaries. The expression of I-15P in the ovaries of immature rats was induced to the level in immature rats by gonadotropin treatment. This suggests that the expression of I-15P in the ovaries is controlled by the ovarian cycle. The present results indicate that the expression of I-15P is developmentally and hormonally controlled in a tissue-specific manner.

Adrenal Glands↗

PubMed1995

Molecular cloning, expression, and characterization of a human intestinal 15-kDa protein.

We have isolated a cDNA encoding a human intestinal 15-kDa protein (I-15P) from a human ileal lambda gt 11 cDNA library, using a full-length rat I-15P cDNA. One clone encompassed 571 nucleotides and encoded a 128-amino-acid protein with a calculated molecular mass of 14355 Da. The deduced amino acid sequence of human I-15P showed high similarity to the rat counterpart (78%), mouse ileal lipid-binding protein (80%) and porcine gastrotropin (75%). It also exhibited 36% similarity to human liver fatty-acid-binding protein (L-FABP). Northern blot analysis of human I-15P revealed a single transcript only in ileum, however, the reverse-transcription/PCR demonstrated expression in ovary and placenta, but it was much lower than in ileum. Transformation of Escherichia coli with the I-15P cDNA resulted in the efficient expression of a protein that was identical to the ileal cytosolic I-15P. In vitro binding studies revealed that the bacterially expressed recombinant I-15P showed much lower affinities for palmitate and oleate than L-FABP. However, it showed similar affinity for taurocholate, compared with a control, BSA. Comparison of the structural features of human I-15P and human L-FABP suggested that loss of a long alpha-helix region and hydrophobic profile of I-15P may be attributable to a unique ligand-binding specificity of I-15P.

Aged↗

PubMed1995

Increase in expression levels of interferon-inducible genes in senescent human diploid fibroblasts and in SV40-transformed human fibroblasts with extended lifespan.

The normal human fibroblast line, TIG-3 which senesces at around 80 population doubling levels (PDLs), expressed interferon (IFN)-inducible genes such as 6-16, 2', 5'-oligoadenylate synthetase (2,5-A) and HLA B7 near the end of the proliferative lifespan. Other normal fibroblast line such as MRC-5 also expressed IFN-inducible genes when senesced. Clones transformed with SV40 T-antigen, which extended their proliferative lifespan by about 20-30 PDLs, also expressed IFN-inducible genes during their extended life. Anti-IFN-beta antibodies added in culture medium repressed the expression of IFN-inducible gene in both normal senescent and life-extended SV40-transformed cells. IFN-beta repressed DNA synthesis in normal TIG-3 and induced IFN-inducible genes in both normal and SV40-transformed TIG-3. Conditioned medium recovered from life-extended SV40-transformed cells contained IFN-beta, but not IFN-alpha, IFN-gamma or TNF-alpha and possessed an activity that inhibited DNA synthesis of young TIG-3. Addition of anti-IFN-beta antibodies into the medium enhanced the serum-induced DNA synthesis of near senescent (91% lifespan completed) TIG-3, while it neither induced DNA synthesis in fully senescent TIG-3 nor extended the proliferative lifespan of TIG-3. These results suggest that normal and SV40-transformed human fibroblasts increase expression of IFN-beta with increasing proliferative age especially near the end of their lifespan resulting in induction of IFN-inducible genes and possibly in growth repression.

Cell Line↗

PubMed1995

Female reproductive properties and prenatal development of a senescence-accelerated mouse strain.

Female reproductive properties, early embryonic development, and serum estradiol and progesterone levels of the senescence-accelerated mouse (SAM)-prone (SAM-P) strain were compared with those of a SAM-resistant (SAM-R) strain. The reproductive life span of SAM-P (from 11.4 to 25.0 weeks old) was shorter than that of SAM-R (11.1 to 41.6 weeks old), and the total number of SAM-P pups was 41.7% less than from SAM-R. The reproductive senescence of SAM-P is more accelerated than that of SAM-R. At 15 weeks old, the maximum litter size of SAM-P was noted and was 33.7% smaller than that of SAM-R. Although no differences in the numbers of ovulated and fertilized ova were observed between two strains, the number of implants in SAM-P was 21.6% less than in SAM-R. Cell cleavage was delayed in embryos of SAM-P (8% morula, at day 2 of pregnancy) compared to SAM-R (48%). At day 3 of pregnancy, 9% and 33% of the embryos were blastocysts in SAM-P and SAM-R, respectively. At day 1 of pregnancy, serum estradiol level in SAM-P was 18.2% higher than in SAM-R, whereas the serum progesterone level in SAM-P was 46.2% lower than in SAM-R. The unbalance of estradiol and progesterone levels in SAM-P was considered to be the cause of the delay in early embryonic development, and then the decrease of implantation and a smaller litter size.

Aging↗

PubMed1995

Midkine is present in the early stage of cerebral infarct.

Expression of midkine (MK), a growth factor with neurotrophic activities, was examined immunohistochemically in experimental cerebral infarct of rats. From postoperative day 1 to day 7 after the onset of infarct, anti-MK immunoreactivity was observed in the surrounding ischemic zone of the infarct but not in the necrotic lesion. The immunoreactive material was identified to be MK by Western blotting. On day 14, anti-MK immunoreactivity became negative. Absence of MK in the normal brain was verified both by immunohistochemical staining and Western blotting. The induced expression of MK is an early event: increased expression of glial fibrillary acidic protein (GFAP), a marker of astrocytes, started on day 4 and continued to day 14. These findings suggest that MK is produced around the site of nerve damage and plays a role as a reparative neurotrophic factor during the early phase of cerebral infarct.

Animals↗

PubMed1995

Increase in expression level of p21sdi1/cip1/waf1 with increasing division age in both normal and SV40-transformed human fibroblasts.

p21sdi1/cip1/waf1 gene, whose product inhibits Cyclin/Cdk kinase and blocks cell proliferation, is known to be up-regulated by p53 and to be expressed at high levels in senescent human fibroblasts. The present paper reports that p21 expression level was much lower in SV40tsT-antigen transformed cells than in normal cells and that after inactivation of tsT-antigen it recovered to that of normal cells. However, cell division age-dependent increase in expression level of p21 occurred not only in normal human fibroblasts but also in SV40tsT-antigen transformed fibroblasts with active T-antigen. These results suggest that cell age-dependent increase in p21 occurs independently upon the function of T-antigen binding proteins including p53, while the basal expression level of p21 is up-regulated by p53 as previously reported.

Antigens, Polyomavirus Transforming↗

PubMed1995

Detection of human T-lymphotropic virus type I (HTLV-I) tax RNA in the central nervous system of HTLV-I-associated myelopathy/tropical spastic paraparesis patients by in situ hybridization.

Autopsy specimens from 3 patients with human T-lymphotropic virus (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) were examined for the presence of HTLV-I in the central nervous system (CNS). In situ hybridization using an HTLV-I tax RNA probe detected cells containing HTLV-I RNA in spinal cord and cerebellar sections. HTLV-I infected cells were located within the white matter and, in particular, within the anterior and lateral funiculi of the spinal cord. Consistent with previously described HAM/TSP pathology, there were perivascular infiltrates in these CNS specimens. Significantly, HTLV-I RNA was not localized to these infiltrates but was detected deeper within the neural tissue. Furthermore, phenotypic analysis demonstrated that at least some of the infected cells were astrocytes. While previous polymerase chain reaction studies have demonstrated the presence of proviral HTLV-I in CNS specimens, here we provide evidence for the in situ expression of HTLV-I RNA in the CNS of HAM/TSP patients.

Aged↗

PubMed1995

Structural changes in the oviductal wall during passage of unfertilized cumulus-oocyte complexes in mice.

BACKGROUND: Little information is available on the structural relationship of cumulus-oocyte complexes and the oviductal wall during the transport of cumulus-oocyte complexes. METHODS: To this end, morphological changes of the oviductal wall during the passage of unfertilized cumulus-oocyte complexes were examined chronologically in ICR mice 25-27 days of age injected with PMSG and hCG. Mice were sacrificed at 12, 14, 16, 18, and 24 hr after the injection of hCG to remove oviducts, and the height of mucosal folds, muscle layers, and epithelial cells was measured in the serial sections stained with hematoxylineosin or colloidal iron. RESULTS: The height of the mucosal fold and muscle layer where cumulus-oocyte complexes were located was less than that of the adjacent portions. At 12-18 hr of hCG injection (approximately 2-8 hr after ovulation), the ova with surrounding cumulus cells lie free in a wide lumen, and the muscular tissue consists of only 2 or 3 layers of cells, arranged mostly longitudinally. However, a neighboring portion without cumulus-oocyte complexes, where the folds meet in the middle, appreciably restricts the free space in the lumen. After 24 hr of hCG administration, structural changes in the oviductal wall, where cumulus-oocyte complexes were located, were no longer apparent. The number of cumulus cells surrounding the oocyte decreased during the passage through the oviduct. At 12-18 hr after hCG injection, approximately 140 cells were identified in the largest cross section of a cumulus-oocyte complex, but after 24 hr of hCG administration (approximately 14 hr after ovulation), an oocyte was surrounded with only approximately 25 cells. CONCLUSIONS: These results indicate that oocyte-cumulus cell complexes influence the structure of the oviductal wall during the passage in the oviduct.

Animals↗

PubMed1995

Structural changes in the oviductal wall during the passage of unfertilized cumulus-oocyte complexes in mice.

BACKGROUND: Little information is available on the structural relationship of cumulus-oocyte complexes and the oviductal wall during the transport of cumulus-oocyte complexes. Then, morphological changes of the oviductal wall during the passage of unfertilized cumulus-oocyte complexes was examined chronologically in ICR mice 25-27 days of age injected with PMSG and hCG. METHODS: Mice were sacrificed at 12, 14, 16, 18, and 24 hr after the injection of hCG to remove oviducts, and the height of mucosal folds, muscle layers, and epithelial cells were measured in the serial sections stained with hematoxylin-eosin or colloidal iron. RESULTS: The height of the mucosal fold and muscle layer where cumulus-oocyte complexes were located was less than that of the adjacent portions. At 12-18 hr of hCG injection (about 2-8 hr after ovulation), the ova with surrounding cumulus cells lie free in a wide lumen, and the muscular tissue consists of only 2 or 3 layers of cells, arranged mostly longitudinally. However, a neighboring portion without cumulus-oocyte complexes, where the folds meet in the middle, appreciably restricts the free space in the lumen. After 24 hr of hCG administration, structural changes in the oviductal wall, where cumulus-oocyte complexes were located, were no longer apparent. The number of cumulus cells surrounding the oocyte decreased during the passage through the oviduct. At 12-18 hr after hCG injection, about 140 cells were identified in the largest cross section of a cumulus-oocyte complex, but, after 24 hr of hCG administration (about 14 hr after ovulation), an oocyte was surrounded with only about 25 cells. CONCLUSIONS: These results indicate that oocyte-cumulus cell complexes influence the structure of the oviductal wall during the passage in the oviduct.

Animals↗

PubMed1995

Expression of prostatic secretory protein (PSP)-like protein in porcine corpus luteum: isolation and characterization of a new gene encoding PSP94-like protein.

cDNA clones encoding stage-and/or space-specific genes in porcine ovarian follicles have been investigated by differential screening of cDNA libraries of granulosa cells and corpus luteum. A clone corresponding to mRNA preferentially expressed in the functional stage of corpus luteum was found to encode a protein similar to the human prostatic secretory protein, PSP94, which had been originally identified in male genital organs. The expression was detected widely in the functional corpora lutea by in situ hybridization histochemistry, but the signal was most prominent in the luteal cells surrounding blood vessels. In contrast, despite the structural similarity in their products, the expression of this newly identified gene was not detected in porcine prostate, suggesting that these structurally related proteins play different roles in mammalian genital organs.

Amino Acid Sequence↗

PubMed1995

Sequence analysis of human T cell lymphotropic virus type I (HTLV-I) Env genes amplified from central nervous system tissues of patients with HTLV-I-associated myelopathy or leukemia.

Human T cell lymphotropic virus type I (HTLV-I) is a retrovirus that has been linked to HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP), a chronic or inflammatory neurological disease with some resemblance to multiple sclerosis. We used the polymerase chain reaction to amplify viral env genes in foci of inflammation and demyelination in the nervous system to adduce additional evidence of the association of HTLV-I with the neuropathological changes in HAM/TSP, and document in this report such an association. We also sought evidence of a distinct viral species in the lesions by amplifying, cloning and sequencing the env genes from tissues sections in which there were pathological changes. We did not find changes in the env gene that correlated with HTLV-I-associated neurological disease vs adult T cell leukemia or with the nervous system vs peripheral blood and lymphoid organs. We did, however, find evidence of extensive mutation and possibly deletions in the env gene in HTLV-I-associated neurological disease. We interpret these findings of increased genetic diversity as a reflection of higher rates of viral replication in HTLV-I-associated myelopathy that support a model of pathogenesis in which increased viral replication activates immune cells that subsequently enter the nervous system and cause injury by immunopathological mechanisms.

Adult↗

PubMed1995

Activation of mitogen-activated protein kinase during meiotic maturation in porcine oocytes.

To investigate the involvement of mitogen-activated protein kinase (MAP kinase) in meiotic maturation of porcine oocytes, we assayed MAP kinase activity using myelin basic protein (MBP) as a substrate. MAP kinase activity was low during the germinal vesicle stage, 0-20 h of culture. An abrupt increase was observed at metaphase I (30 h of culture), and activity remained significantly higher than that at 0 h until 50 h of culture, with a transient slight decrease at the time of first polar body extrusion (40 h). Detection of the kinase activity by an in-gel phosphorylation assay confirmed that the 42 and 44 kDa MAP kinases were significantly activated in 45 h cultured oocytes but not in 0 h oocytes, and just slightly in 20 h oocytes. In immunoblotting, however, the 42 and 44 kDa bands were detected in 0, 20 and 45 h cultured oocytes. Furthermore, the signal strength of the two bands did not change during the period of culture, but shifted up to 45 h, indicating that the activation of MAP kinase depended not on the synthesis but on the phosphorylation of this enzyme. These results suggest that the activation of MAP kinase is involved in the regulation of meiotic maturation of porcine oocytes, and especially in the regulation after germinal vesicle breakdown.

Animals↗

PubMed1995

Synchronous sperm penetration of zona-free mouse eggs in vitro.

To synchronize sperm penetration of zona-free eggs immediately after insemination, zona-free eggs preloaded with Hoechst-33342 were inseminated under various conditions. Insemination was mostly conducted at 10 sperm/microliter. In preliminary experiments, fatty acid-free BSA (FAF) was more satisfactory for sperm penetration than fraction V BSA, and FAF was used in the following experiments. Only 26% of zona-free eggs were fertilized at 10 min after insemination when the eggs were inseminated immediately after zona removal and preloading. However, egg preincubation significantly improved the penetration rate (1 h preincubation: 63%, 2 h preincubation: 82% penetrated 10 min after insemination). Some eggs preincubated for 2 h were already penetrated at 3 min (7%), and the rate gradually increased in a time-dependent manner (3 min: 7%, 5 min: 30%, 10 min: 80%). The rate further improved as the sperm concentration was increased; the maximal level was obtained at 160 sperm/microliters. At 160 sperm/microliters, 54% of the eggs were penetrated at 3 min and 78% were at 5 min. These results indicate that it is possible to synchronize the sperm entry and that not only sperm but zona-free eggs should be preincubated before insemination. These data are considered valuable for investigating early events in fertilization.

Animals↗

PubMed1995

Expression of sulfomucins in normal mucosae, colorectal adenocarcinomas, and metastases.

We have examined the expression of specific mucin antigens in tissue sections from 92 cases of colorectal carcinoma, using sulfomucin-specific monoclonal antibody (MAb) 91.9H. The expression of sulfomucins was high in normal mucosae and much lower in primary colorectal carcinoma, in metastatic lesions in lymph nodes or in liver. The intracellular localization of sulfomucins was also different among these tissues. In normal mucosae, MAb 91.9H binding was seen in the supranuclear area, presumably Golgi complexes, the luminal surface, and secretory products. In primary colorectal carcinomas and in their metastatic lesions, MAb 91.9H was preferentially localized in the cell surface and substances attached to the luminal surface of glandular structures. Analysis of the lysates of normal and tumor tissues showed that very-high-molecular-weight components contained the antigenic epitopes. The intensity of MAb 91.9H binding was lower in tumors at advanced stages than in tumors at early stages. These high-molecular-weight components were apparently reactive with MAb FH6 specific for sialyl-Le(X) (s-Le(X) structures. Histological specimens with low levels of MAb 91.9H reactivity often exhibited relatively high levels of MAb FH6 reactivity. These two mucins may have reversed expression during carcinogenesis and carcinoma progression, and this change may be related to metastatic potential.

Adenocarcinoma↗

PubMed1995

Mucin antigens expression and Ki-67 labeling in breast cancer: the peculiarity in scirrhous carcinoma.

The expression of mucin-related antigens (Tn, T, Sialosyl-Tn [STn], DF3 [mammary-type apomucin related antigen], and intestinal-MRP [intestinal-type apomucin related antigen]) as well as Ki-67 labeling was examined in 58 mammary invasive ductal carcinomas (IDC) divided into 26 scirrhous subtype (SC) and 32 non-scirrhous subtype comprising papillotubular carcinoma and solid-tubular carcinoma (PT-ST). These data were analyzed in connection with the various pathological prognostic factors such as nodal status, tumor size, estrogen receptor status and histological grading of carcinomas. The results were as follows: (a) in SC, the expression rate of Tn was significantly higher in the cases with positive lymph node metastasis or with large tumor size (> 2 cm) than in those with negative lymph node metastasis or with small tumor size (< or = 2 cm); (b) in PT-ST, the expression rate of STn was higher in the cases with positive lymph node metastasis or with large tumor size than in those with negative lymph node metastasis or with small tumor size; (c) in SC, Ki-67 labeling was significantly higher in the cases with positive lymph node metastasis than in those with negative lymph node metastasis; and (d) in PT-ST, Ki-67 labeling was lower in the cases with positive lymph node metastasis than in those with negative lymph node metastasis. In conclusion, Tn antigen expression was correlated with pathological prognostic factors in SC but not in PT-ST, whereas STn antigen expression was correlated with pathological prognostic factors in PT-ST but not in SC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma, Scirrhous↗

PubMed1995

Effectiveness of Carolina rinse solution after cold ischemic storage of rat livers: biochemical and histological analysis using perfusion model.

Using a rat liver perfusion model, the effectiveness of Carolina rinse solution was assessed for the prevention of reperfusion injury after 48 h of cold storage in UW solution. Transaminase levels (GOT, GPT and LDH) of the perfusate were significantly higher in the Ringer group (17 +/- 8, 17 +/- 9 and 191 +/- 97 IU/l, respectively) than in the Carolina group (6 +/- 4, 5 +/- 4 and 21 +/- 20 IU/l) (p < 0.05). The levels of oxygen consumption were also higher in the Carolina group (233 +/- 54 mm Hg) than in the Ringer group (164 +/- 58 mm Hg) (p < 0.05). Histological examination showed severe parenchymal cell damage in the Ringer group, whereas the damage was slight in the Carolina group. Two newly developed monoclonal antibodies, REC16-11 and REC4-1, which specifically react with rat endothelial cells, were used for immunohistochemical studies of the livers. The endothelial cells of central vein and sinusoids were more severely damaged in the Ringer group than in the Carolina group. The present study suggests that Carolina rinse solution is useful for prevention of liver damage from reperfusion injury after cold storage of the graft for organ transplantation.

Animals↗