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Biomedical subjects

S Takeuchi

Publications and source records attributed to S Takeuchi.

At least 55 records · Page 3Linked to original sources
PubMed2001

Expression and action of hepatocyte growth factor in bovine endometrial stromal and epithelial cells in vitro.

Hepatocyte growth factor (HGF) is a pleiotropic growth factor that acts on various epithelial cells. The objectives of this study were to determine whether HGF altered the proliferation and prostaglandin (PG) secretion of bovine endometrial stromal and epithelial cells in vitro. We also observed HGF and HGF receptor (c-met) mRNA expression in cultured bovine endometrial stromal and epithelial cells by RT-PCR. Stromal and epithelial cells obtained from cows in early stage of the estrous cycle (days 2-5) were cultured in DMEM/Ham's F-12 supplemented with 10% calf serum. The cells were exposed to HGF (0-10 ng/ml) for 2, 4, or 6 days. HGF significantly increased the total DNA in epithelial (P < 0.05), but not stromal cells. In another experiment, when the cells reached confluence, the culture medium was replaced with fresh medium with 0.1% BSA containing HGF 0-100 ng/ml and the cells were cultured for 24 hr. The HGF stimulated PGF2alpha secretion in epithelial, but not stromal cells. RT-PCR revealed that mRNA of HGF is expressed only in stromal cells, and that c-met mRNA is expressed in both stromal and epithelial cells. These results suggest that HGF plays roles in the proliferation and the regulation of secretory function of bovine endometrial epithelial cells in a paracrine fashion.

Animals↗
PubMed2001

Signaling mechanism underlying COX-2 induction by lysophosphatidylcholine.

Lysophosphatidylcholine, a component of oxidized low density lipoprotein, is critical for pathological conditions including atherosclerosis. However, the signaling mechanism of lysophosphatidylcholine remains poorly understood. Here we reported that lysophosphatidylcholine induces phosphorylation of p38 and the transcription factors, CREB and ATF-1 with concomitant up-regulation of cyclooxygenase-2 expression in cultured vascular endothelial cells. Lysophosphatidylcholine induced p38 phosphorylation in a time- and concentration-dependent manner partly via pathway depending on protein tyrosine kinase. Both lysophosphatidylcholine-stimulated phosphorylation of CREB and ATF-1 and lysophosphatidylcholine-increased expression of cyclooxygenase-2 mRNA and protein were effectively inhibited by a combination of SB203580 and PD98059, specific inhibitors of p38 and MEK1, respectively, as well as Ro31-8220 and H89, potent inhibitors of MSK1. These results suggest that both p38 and ERK may function as upstream signaling pathways capable of activating CREB and ATF-1 with subsequent induction of cyclooxygenase-2 expression by lysophosphatidylcholine.

Activating Transcription Factor 1↗
PubMed2001

Jaundice after surgery for an aortic arch aneurysm.

A 57-year-old patient who developed hyperbilirubinemia after surgery for an aortic arch aneurysm subsequently suffered pseudomonas sepsis. Low-volume biliary drainage from the common bile duct was colorless. A disturbance in the liver's excretory system caused jaundice. Sepsis and jaundice were resolved when hepatic excretory function recovered.

Aortic Aneurysm, Thoracic↗
PubMed2001

Chronic dissecting aneurysm of the thoracic aorta following minor blunt trauma.

A 64-year-old man admitted for treatment of a thoracic aneurysm had experienced severe back pain 10 years earlier after falling heavily on his forearms. From the night following the fall, hoarseness and pleuritic chest wall pain continued for about 3 months. Preoperative imaging showed a chronic dissecting aneurysm near the aortic isthmus. The patient's history suggested that the fall 10 years before surgery was the most likely cause.

Aortic Dissection↗
PubMed2001

Indications for surgical treatment of funnel chest by chest radiograph.

Forty-seven children with funnel chest (FC) who underwent sternal elevation and 210 normal children were examined to determine the indications for surgical treatment using the vertebral index (VI) and frontosagittal index (FSI). In normal children VI gradually increased and FSI gradually decreased with age. Both indices changed significantly at 3 years of age. Although the VI of FC patients decreased significantly from 33.8 +/- 7.6 (n=40) to 24.4 +/- 3.9 (n=38) postoperatively (P < 0.0001), it was significantly larger than that of normal children over 3 years of age (20.2 +/- 2.2, n=150) (P < 0.0001), and although the FSI of FC patients increased significantly from 22.0 +/- 7.0 (n=40) to 34.5 +/- 6.5 (n=38) postoperatively (P < 0.0001), it was significantly smaller than that of normal children over 3 years of age (41.1 +/- 4.0, n=150) (P < 0.0001). Since many patients had a thin and flat chest despite excellent correction, their postoperative indices were not normal. There was a correlation between VI and FSI in normal children and a high degree of correlation between VI and FSI both before and after operation in FC patients. We conclude that a VI of more than 27 and/or a FSI of less than 29 are indications for surgical treatment based on the mean VI + 3SD and FSI - 3SD of normal children over 3 years of age. These values are almost equal to the mean VI - SD and FSI + SD of patients with physical, cosmetic, and/or psychological disturbances. However, it is not necessary to measure both indices simultaneously. Postoperative VI and FSI did not always reflect the degree of chest-wall depression in FC patients because of their flat chests.

Adolescent↗
PubMed2001

Morphological and functional analyses of diabetic macular edema by optical coherence tomography and multifocal electroretinograms.

PURPOSE: To determine the correlation between the tomographic features and the visual functions of eyes with diabetic macular edema. METHODS: Optical coherence tomographic (OCT) images and multifocal electroretinograms were obtained from 45 eyes of 25 patients with diabetic macular edema and from 21 eyes of 21 normal subjects. RESULTS: The OCT images showed cystoid macular edema in 18 eyes and diffuse retinal swelling without cystoid edema in the other 27 eyes. The fovea was significantly thicker in eyes with cystoid macular edema and in those with diffuse retinal swelling than in normal eyes. The fovea of eyes with cystoid edema was significantly thicker than the fovea of eyes with diffuse swelling. The best-corrected visual acuity and the electrical response density from the macular area were significantly reduced in eyes with diabetic macular edema, particularly in those with cystoid edema. The best-corrected visual acuity and macular response density of the multifocal ERGs were inversely correlated, and the implicit times were directly correlated with foveal thickness. CONCLUSION: The visual acuity was correlated significantly with morphological changes revealed by OCT and with multifocal ERGs. The combination of OCT and multifocal ERGs may provide objective criteria for the evaluation and assessment of diabetic macular edema.

Adult↗
PubMed2001

Implications of adrenomedullin expression in the invasion of squamous cell carcinoma of the uterine cervix.

BACKGROUND: Adrenomedullin (AM) is a multifunctional peptide involved in a variety of physiological functions, including vasodilatation, growth regulation, and carcinogenesis. To elucidate the possible role of AM in the growth and invasion of uterine cervical carcinoma, the presence and distribution of AM and AM mRNA was examined in the neoplastic changes of squamous epithelium of the uterine cervix. METHODS: The expression of AM mRNA by CaSki, a uterine squamous cell carcinoma cell line, was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). The presence and distribution of AM and AM mRNA in sections of normal cervical tissues, cervical intraepithelial neoplasia (CIN), and invasive squamous cell carcinomas were evaluated by immunohistochemical staining with a specific antibody against AM and by in situ RT-PCR, respectively. RESULTS: AM mRNA expression in CaSki cells was demonstrated by RT-PCR. Immunohistochemical staining for AM and in situ RT-PCR revealed that AM and AM mRNA were expressed in invasive squamous carcinoma cells, but not in normal cervical epithelium or in CIN lesions. Abundant expression of AM and AM mRNA was localized in the cytoplasm of carcinoma cells of bulky invasive carcinomas, while in early invasive carcinoma, the expression of AM and AM mRNA was more prominent in stromal cells adjacent to the early invasive carcinoma cells than in the carcinoma cells themselves. CONCLUSIONS: Because AM expression was evident only in invasive cervical squamous carcinoma cells and the stromal cells adjacent to early invasive carcinomas, it is likely that AM may play an important role in the growth and invasion of squamous cell carcinoma of the uterine cervix.

Adrenomedullin↗
PubMed2001

Vitrectomy for diabetic macular edema: the role of posterior vitreous detachment and epimacular membrane.

PURPOSE: To evaluate the surgical efficacy of pars plana vitrectomy on eyes with diabetic macular edema in the presence or absence of a complete posterior vitreous detachment and with or without an epimacular membrane. METHODS: Pars plana vitrectomy was performed on 30 eyes of 29 cases with diabetic macular edema. Visual acuity was measured, and retinal thickness was determined by optical coherence tomography before and after vitrectomy. To evaluate the relationship between the effects of vitrectomy and the presence or absence of posterior vitreous detachment and/or epimacular membrane, all eyes were placed into one of four groups: group A, eyes with posterior vitreous detachment and epimacular membrane; B, eyes with posterior vitreous detachment and without epimacular membrane; C, eyes without posterior vitreous detachment and with epimacular membrane; and D, eyes without posterior vitreous detachment and without epimacular membrane. The expression of vascular endothelial growth factor and interleukin-6 was investigated immunohistochemically in epimacular membrane specimens obtained from seven eyes with diffuse diabetic macular edema. RESULTS: The postoperative mean visual acuity (0.653 +/- 0.350: mean +/- SD logarithm of minimal angle of resolution [logMAR]) was significantly better than the mean preoperative visual acuity (0.891 +/- 0.319 logMAR; Wilcoxon signed-rank test, P =.0007). The postoperative foveal thickness (264.5 +/- 118.6 microm) was significantly thinner than the preoperative foveal thickness (477.8 +/- 147.7 microm; Wilcoxon signed-rank test, P <.0001). There were no significant differences in the improvement of visual acuity and decrease of foveal thickness between the four groups (Kruskal-Wallis test, P =.13, P =.65, respectively). All of the epimacular membranes obtained at surgery expressed vascular endothelial growth factor and interleukin-6. CONCLUSIONS: These results demonstrated that vitrectomy with removal of epimacular membrane is generally an effective procedure in reducing diabetic macular edema, and the outcome does not depend on the presence absence of posterior vitreous detachment and epimacular membrane.

Aged↗
PubMed2001

Macular fold after limited macular translocation treated with scleral shortening release and intravitreal gas.

PURPOSE: To describe a case developing a macular fold as a complication of limited macular translocation, which was successfully managed without repeat vitrectomy. METHODS: Interventional case report. A 34-year-old woman who underwent limited macular translocation for subfoveal choroidal neovascularization secondary to myopic degeneration developed a postoperative macular fold. Her visual acuity deteriorated from 20/100 to 20/200 postoperatively. RESULTS: She underwent scleral shortening release and intravitreal gas injection 4 days after the initial surgery and had a resolution of macular fold with adequate foveal displacement. Her visual acuity had improved to 20/40 3 months postoperatively. CONCLUSION: Scleral shortening release and intravitreal gas injection may be considered for the management of severe macular fold caused by limited macular translocation.

Adult↗
PubMed2001

Hemodynamic evaluation of 19-mm Carpentier-Edwards pericardial bioprosthesis in aortic position.

BACKGROUND: The aortic Carpentier-Edwards pericardial bioprosthesis offers good long-term clinical outcomes with a low rate of structural deterioration. However, little in vivo hemodynamic data is available for this bioprosthesis. METHODS: To determine the hemodynamic performance of the 19-mm Carpentier-Edwards pericardial valve, both cardiac catheterization and dobutamine stress echocardiography were electively performed in 10 patients. The mean age at the study was 71.6 +/- 4.4 years and the mean body surface area was 1.39 +/- 0.11 m2. The peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area were measured by standard cardiac catheterization. The Doppler-derived gradients and valve orifice area were also measured both at rest and during dobutamine infusion. RESULTS: The average peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area measured by catheterization were 13.0 +/- 5.4 mmHg, 28.5 +/- 7.7 mmHg, 12.0 +/- 4.9 mmHg, and 1.55 +/- 0.45 cm2, respectively. The peak and mean Doppler gradients, and valve orifice area by resting echocardiography were 27.7 +/- 9.5 mmHg, 12.3 +/- 4.8 mmHg, and 1.39 +/- 0.26 cm2, respectively. At a dosage of 10 microg/kg/min of dobutamine, the mean Doppler gradient rose mildly to 22.2 +/- 4.8 mmHg, while the cardiac output increased from 4.49 +/- 0.44 to 6.64 +/- 0.87 L/min. The valve orifice area during the 10 microg/kg/min dobutamine infusion (1.55 +/- 0.25 cm2) was significantly larger than its value at rest (p < 0.05). CONCLUSIONS: With acceptable hemodynamic performance, use of the aortic 19-mm Carpentier-Edwards pericardial valve is a reliable option for elderly patients with a small annulus.

Aortic Valve↗
PubMed2001

A prospective randomized comparison of routine buserelin acetate and a decreasing dosage of nafarelin acetate with a low-dose gonadotropin-releasing hormone agonist protocol for in vitro fertilization and intracytoplasmic sperm injection.

OBJECTIVE: To compare the efficacy of a draw-back nafarelin acetate protocol with routine buserelin acetate administration for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). DESIGN: Prospective clinical study. SETTING: Mie University School of Medicine, Tsu, Mie, Japan. PATIENT(S): One hundred sixty-nine women treated with IVF and 183 women treated with ICSI. INTERVENTION(S): Nafarelin acetate and buserelin acetate in ovarian hyperstimulation in IVF and ICSI were administered. MAIN OUTCOME MEASURE(S): The concentrations of estradiol (E(2)), FSH, LH, gonadotropin dosages; the number of oocytes retrieved, oocytes fertilized, and embryos; and pregnancy rates. RESULT(S): A prospective study was conducted with 44 cycles for 34 couples with nafarelin acetate (group 1) and 47 cycles for 40 couples with buserelin acetate (group 2) with a long IVF protocol; 68 cycles for 46 couples with nafarelin acetate (group 3) and 56 cycles for 39 couples with buserelin acetate (group 4) with a short IVF protocol; 39 cycles for 32 couples with nafarelin acetate (group 5) and 50 cycles for 30 couples with buserelin acetate (group 6) with a long ICSI protocol; and 87 cycles for 60 couples with nafarelin acetate (group 7) and 81 cycles for 61 couples with buserelin acetate (group 8) with a short ICSI protocol. Patients were randomized to receive either full-dose nafarelin acetate (200 microg b.i.d.) treatment for 7 days followed by half-dose nafarelin acetate (200 microg daily) or buserelin acetate (300 microg t.i.d.). There were no statistically significant differences in baseline concentrations of E(2) and FSH, concentrations of E(2), P4, FSH, LH on hCG administration, gonadotropin dosage, the number of oocytes retrieved and embryos transferred, or pregnancy rates between groups 1 and 2, groups 3 and 4, groups 5 and 6, and groups 7 and 8. CONCLUSION(S): Full-dose nafarelin acetate treatment for 7 days followed by half-dose nafarelin acetate ("draw-back" protocol) is an effective new protocol for IVF and ICSI.

Abortion, Spontaneous↗
PubMed2001

Mutation analysis of the DNA-damage checkpoint gene CHK2 in myelodysplastic syndromes and acute myeloid leukemias.

Checkpoint genes code for a family of proteins which sense DNA damage in eukaryotic cells. They play an important role in the control of the cell cycle. The human CHK2 is a homolog of the yeast G(2) checkpoint kinases known as CDS1 and RAD53. The CHK2 may be a tumor suppressor gene because it was found to be mutated in some individuals with the Li-Fraumeni syndrome. These cases had a normal, non-mutated p53 gene. We performed a mutational analysis of the CHK2 gene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) in 41 bone marrow samples from individuals with myelodysplastic syndrome (MDS) and 41 samples of acute myeloid leukemias (AML). We found a novel G to C transversion resulting in a change from Ala to Gly at codon 507 of CHK2 in one MDS sample, but normal cells from this individual did not have the abnormality. In addition, we demonstrated a previously described polymorphism at codon 84 (A to G at nucleotide 252) of exon 1 of CHK2 in three of 41 MDS and three of 41 AML patients. The presence of a CHK2 mutation in MDS highlights the importance of alterations of cell cycle checkpoint genes in this disease.

Acute Disease↗
PubMed2001

Frequent loss of heterozygosity in the region of D1S450 at 1p36.2 in myelodysplastic syndromes.

To understand the underlying mechanisms in myelodysplastic syndromes (MDS) by identifying target tumor suppressor genes, we performed a detailed deletional mapping of the short arm of chromosome 1 in 38 paired samples of bone marrow and peripheral blood obtained from individuals with MDS by PCR amplification of a total of 23 highly informative microsatellite sequences. We identified the commonly deleted region between D1S508 and D1S244. LOH of this region was found in five patients (13%). In addition, LOH at 1p was associated with a poor clinical outcome, suggesting that the deletion of a gene in this region may be involved in the course of this disease. By analyzing the chromosomal map of this region, we found TNFRSF12 as a candidate tumor suppressor gene. However, our search for mutations in this gene did not identify somatic mutations in MDS. Our findings are consistent with the possible existence of an as-yet unknown tumor suppressor gene in this region that is altered in MDS.

Adult↗
PubMed2001

Three-dimensional and ultrastructural relationships between intermediate cells and capillaries in the gerbil stria vascularis.

Structural relationships between intermediate cells and capillaries in the stria vascularis of gerbils were examined by confocal laser microscopy and electron microscopy. Immunostaining for an inward rectifier K(+) channel (Kir4.1), which was localized to intermediate cells, was used to determine the three-dimensional distribution of intermediate cells. These cells constituted a honeycomb-like network, and their dendritic processes surrounded not only capillaries but also the basolateral surface of epithelial marginal cells. On the basis of the above finding and the large K(+) conductance in intermediate cells, we propose that the network composed of intermediate cells has a spatial K(+) buffering function. Transmission electron microscopy revealed the absence of the basal lamina in some regions and the presence of a gap junction-like membrane association between intermediate cells and pericytes and/or endothelial cells. This result supported our previous finding that intermediate cells were dye-coupled with pericytes and endothelial cells. The presence of gap junctions between intermediate cells and pericytes and/or endothelial cells suggests that endothelial cells and pericytes may play roles other than forming a structural route for blood circulation.

Animals↗
PubMed2001

Distribution of protein motors along the lateral wall of the outer hair cell.

The outer hair cell (OHC) plays an important role in the normal functioning of the cochlea, and cochlear amplification is believed to be based on OHC electromotility. This electromotility putatively arises from a conformational change of molecules, i.e., 'protein motors', which would be distributed along the plasma membrane. Although it has been assumed that protein motors are distributed in a restricted area of the plasma membrane, details of such distribution remain unclarified. In this study, first, in order to understand the difference in the stiffness along the cell axis, the local deformation of the OHC in response to hypotonic stimulation is analyzed by measuring the displacement of microspheres attached randomly to the lateral wall of the cell. As a result, the stiffness is expected to be constant throughout the region except in the apical part of the cell, and the stiffness of the apical part is expected to be higher than that of the other regions. Then, the local elongation and contraction of the OHC in response to sinusoidal voltage stimulation are analyzed by measuring the displacement of the microspheres in the same way as in the case of the hypotonic stimulation. From the two measurements mentioned above, it is concluded that there are no motors in the apical and basal parts of the cell, and that the motors are equally distributed along the cell lateral wall in the middle part of the cell.

Animals↗
PubMed2001

Usefulness of vacuum-assisted cardiopulmonary bypass circuit for pediatric open-heart surgery in reducing homologous blood transfusion.

OBJECTIVE: Open-heart surgery without homologous blood transfusion is still difficult in children because priming volume in cardiopulmonary bypass circuit results in extreme hemodilution. Vacuum-assisted cardiopulmonary bypass circuit has the benefit of improving venous return and results in lowering priming volume. We introduced vacuum-assisted cardiopulmonary bypass circuit in order to reduce priming volume for pediatric patients in March 1995. A retrospective study was made on the efficacy of vacuum-assisted circuit for pediatric open-heart surgery in reducing homologous blood transfusion. METHODS: Patients weighing from 5 to 20 kg who underwent surgery between January 1991 and June 1996 were divided into two groups, group A comprised 128 patients before introduction of this circuit and group B comprised 49 patients after introduction, and their clinical course was compared. Vacuum-assisted circuit was used in 27 patients of group B. RESULTS: The percentage of transfusion-free operations was significantly higher in group B than in group A (33.6% in group A vs. 53.1% in group B, P = 0.014), and particularly this percentage in patients weighing less than 10 kg significantly increased (0% in group A vs. 42.9% in group B, P < 0.01). The amount of homologous blood transfusion was significantly lower in group B than in group A (374 +/- 362 ml in group A and 212 +/- 287 ml in group B, P < 0.01). The rate of complications and the duration of respiratory support did not differ between the two groups. The duration of hospital stay was lower in group B than in group A. CONCLUSIONS: The findings of this study indicate that vacuum-assisted circuit is useful for pediatric open-heart surgery in reducing homologous blood transfusion.

Blood Transfusion↗
PubMed2001

Appendiceal carcinoma invading the urinary bladder.

A case is reported of a 78-year-old woman with appendiceal carcinoma invading the bladder causing irritative symptoms. Although several imaging studies suggested that the secondary bladder tumor was of cecal or appendiceal origin, such as abscess or mucocele, histologic findings on transurethral and transvaginal biopsy were inconclusive. However, following laparotomy, pathologic examination of the frozen sections revealed a mucinous cystadenocarcinoma originating in the appendix and a right hemicolectomy and en bloc partial cystectomy were performed. One year after the operation, the patient was well with no evidence of recurrent cancer.

Aged↗