Biomedical subjects

Y Yoshimura

Publications and source records attributed to Y Yoshimura.

At least 163 records · Page 9Linked to original sources

PubMed1998

Cloning and characterization of mouse mSox13 cDNA.

A novel SRY-related cDNA, mSox13, was isolated from a lambda phage library derived from mouse embryo. The cDNA encodes a protein of 595 amino acids containing the SRY-type high mobility group (HMG) box and a putative leucine zipper motif. A sequence comparison of mSox13 and other type-D SOX proteins shows that the leucine zipper and a neighboring glutamine-rich sequence stretch, which was named Q box, are well conserved among known type-D SOX proteins. The expression of mSox13 is restricted to the kidney and ovary. The electrophoretic mobility shift assay indicates that the recombinant mSox13 protein is capable of binding to the AACAAT sequence.

Amino Acid Sequence↗

PubMed1998

Functional competence of T cells in the absence of glycosylphosphatidylinositol-anchored proteins caused by T cell-specific disruption of the Pig-a gene.

T lymphocytes express various glycosylphosphatidylinositol (GPI)-anchored surface proteins, such as Thy-1 and Ly-6A. However, functional contribution of GPI-anchored proteins in T cell activation is as yet poorly understood. Here we report the generation of mutant mice deficient in the expression of GPI-anchored molecules exclusively in their T cells. We established mice carrying three identically oriented lox-P sites within the Pig-a gene, which encodes a component essential for the initial step of GPI anchor biosynthesis. These mice were crossed with mice carrying the Cre recombinase gene driven by the T cell-specific p56lck proximal promoter. Offspring carrying both the lox-P-containing Pig-a gene and the Cre transgene exhibited almost complete loss of the surface expression of GPI-anchored molecules on peripheral T cells. Interestingly, those T cells deficient in GPI-anchored molecules were capable of responding to T cell receptor stimulation in vitro and in vivo. These results indicate that T cells lacking the expression of GPI-anchored molecules are functionally competent in exerting TCR-mediated immune responses.

Alleles↗

PubMed1998

Ultrastructural evaluation following catheterization of the fallopian tube with a hysteroscopic catheter.

PURPOSE: Our purpose was to assess the morphology and ultrastructural changes in the tubal epithelium following catheterization of the fallopian tube. METHODS: Fallopian tubes were obtained from 20 women who had undergone hysterectomies. Catheterization was performed in 20 tubes using a catheter developed for hysteroscopic tubal embryo transfer. The catheter has a 3-French diameter, tapering to 2 French (0.66 mm) at the tip portion. The 20 contralateral tubes served as controls and were not catheterized. Ultrastructural changes were examined by scanning electron microscopy and transmission electron microscopy. RESULTS: Scanning electron microscopy showed no transformation or defects of the tubal epithelium surface in catheterized or control tubes. Transmission electron microscopy showed no significant differences in the percentage of abnormal desmosomes and the percentage of basement membrane in ciliated and nonciliated cells between catheterized and noncatheterized tubes. No transformation or defects were observed in catheterized or noncatheterized tubes. CONCLUSIONS: These findings suggest that catheterization of the tube using a hysteroscopic catheter caused no acute damage to the tubal epithelium.

Basement Membrane↗

PubMed1998

Haemodynamic effects of induction of general anaesthesia with propofol during epidural anaesthesia.

PURPOSE: To clarify whether propofol administration during thoracic or lumbar epidural anaesthesia intensifies the haemodynamic depression associated with epidural anaesthesia. METHODS: Patients (n = 45) undergoing procedures of similar magnitude were randomly divided into three study groups: a control group (n = 15) receiving general anaesthesia alone and two study groups undergoing thoracic (n = 15) and lumbar epidural anaesthesia (n = 15) before induction of general anaesthesia. All patients received 2 mg.kg-1 propofol at a rate of 200 mg.min-1, followed by a continuous infusion of 4 mg.kg-1.hr-1. Mean arterial blood pressure (MAP) and heart rate (HR) were measured at baseline, three minutes after induction, and one minute after tracheal intubation in all three groups and at 20 min after epidural anaesthesia was established in the thoracic and lumbar groups. RESULTS: Following epidural anaesthesia, MAP decreased from 94 +/- 14 (SD) at baseline to 75 +/- 11 mmHg (P < 0.0001) in the thoracic group and from 92 +/- 12 to 83 +/- 15 mmHg in the lumbar group. After propofol administration, MAP decreased further in the thoracic group to 63 +/- 9 mmHg (P = 0.0077) and to 67 +/- 10 mmHg (P = 0.0076) in the lumbar group. The MAP following propofol induction in the thoracic group (P < 0.0001) and in the lumbar group (P = 0.0001) was lower than MAP in the control group (81 +/- 9 mmHg). HR decreased only in response to thoracic epidural anaesthesia (P = 0.0066). CONCLUSION: The hypotensive effects of propofol are additive to those of epidural anaesthesia, resulting in a profound decrease in mean arterial pressure.

Analysis of Variance↗

PubMed1998

Phosphorylation-dependent reversible translocation of Ca2+/calmodulin-dependent protein kinase II to the postsynaptic densities.

The translocation of soluble Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) to postsynaptic densities (PSDs) was investigated. When soluble CaM kinase II previously autophosphorylated was incubated with PSDs, the kinase was precipitated by centrifugation, indicating that the soluble kinase associated with PSDs and formed a PSD-CaM kinase II complex. Ca2+-independent activity generated by autophosphorylation of the kinase was retained in the complex. A number of PSD proteins were phosphorylated by the kinase associated with PSDs in both the absence and presence of Ca2+. When PSD-CaM kinase II complex was incubated at 30 degrees C, the enzyme was dephosphorylated and released from the complex. These results indicate that CaM kinase II reversibly translocates to PSDs in a phosphorylation-dependent manner.

Animals↗

PubMed1998

Epidermal growth factor receptor-mediated expression of NF-kappaB transcription factor in osteoblastic MC3T3-E1 cells cultured under a low-calcium environment.

We examined the effect of a low calcium environment on DNA-protein binding reaction activity of the transcription factor, NF-kappaB in osteoblastic MC3T3-E1 cells, using an electrophoretic mobility shift assay. Binding sites for the NF-kappaB sequence in DNA in nuclear protein in MC3T3-E1 cells are present. This DNA-protein binding reaction activity increased in MC3T3-E1 cells with EGF treatment, compared with those with no treatment. When MC3T3-E1 cells were placed in a low calcium environment, DNA-protein binding reaction activity seemed to decrease. This suggests that the phosphorylation of IkappaB is less active in a low calcium environment as compared with that in a normal calcium environment, because the activation of NF-kappaB is required for the dissociation of the cytoplasmic heterodimer after the phosphorylation of IkappaB. From these facts, it was suggested that gene transcription factor NF-kappaB is intimately associated with inhibitory bone formation in osteoblastic cells.

Animals↗

PubMed1998

Prenatal ultrasound diagnosis of small-bowel torsion.

BACKGROUND: We report a case of congenital small-bowel torsion detected by prenatal ultrasonographic examination. CASE: A 27-year-old primigravida was found to have a fetus with a small-bowel obstruction by ultrasound examination during the third trimester. At 35 weeks of gestation, she complained of absence of fetal activity. A nonstress test showed a nonreactive pattern with reduced baseline variability. Sonographic examination revealed heterogeneous echogenicity within the dilated bowel, and loss of peristalsis. Also noted was a small amount of fetal ascites. After birth, torsion of the dilated small bowel associated with ileal atresia was found at exploratory laparotomy. CONCLUSION: Serial sonographic examinations with special attention to changes in the dilated bowel are useful in the management of prenatally diagnosed small-bowel obstruction.

Female↗

PubMed1998

Anti-herpesvirus activity profile of 4'-thioarabinofuranosyl purine and uracil nucleosides and activity of 1-beta-D-2'-fluoro-4'-thioarabinofuranosyl guanine and 2,6-diaminopurine against clinical isolates of human cytomegalovirus.

Newly synthesized 4'-thio- and 2'-fluoro-4'-thioarabinofuranosyl purine and pyrimidine nucleosides were compared with the corresponding 4'-oxo type arabinosyl nucleosides for anti-herpesvirus and anti-cell proliferative potencies. 4'-Thioarabinosyl- and 2'-fluoro-4'-thioarabinofuranosyl 5-substituted uracils had selective antiviral activities, but were not superior to 4'-oxo nucleosides, except for the activity of 5-ethyl-uracil 4'-thio nucleosides against herpes simplex virus. Furthermore, 4'-thio substituted derivatives of sorivudine (BV-araU) and related compounds, and 2'-fluoro-5-methyl-arabinosyluracil exhibited reduced activity against varicella-zoster virus compared with the parent compounds. The 4'-thioarabinosyluracils, except for 5-methyluracil derivatives, were inactive against human cytomegalovirus (HCMV). 4'-Thioarabinofuranosyl guanine and diaminopurine had the most potent anti-HCMV and anti-proliferative activities, whereas arabinosyl guanine and diaminopurine had only marginal antiviral activity. 2'-Fluoro-4'-thioarabinofuranosyl derivatives of guanine (4'-thio-FaraG) and 2,6-diaminopurine (4'-thio-FaraDAP), however, had particularly high activity against all herpesviruses tested with anti-proliferative activity equipotent to that of arabinosyl guanine and diaminopurine. 4'-Thio- and 2'-fluoro-4'-thioarabinofuranosyladenines exhibited biological activities similar to that of arabinosyladenine. Both 4'-thio-FaraG and 4'-thio-FaraDAP had a 6-fold lower ED50 than ganciclovir against clinical isolates of HCMV. A ganciclovir-resistant isolate, obtained from a patient who had received long-term ganciclovir-treatment, was susceptible to 4'-thio-FaraG and 4'-thio-FaraDAP.

Antiviral Agents↗

PubMed1998

Determination of l-menthol in pharmaceutical products by high performance liquid chromatography with polarized photometric detection.

A simple analytical method for l-menthol by high-performance liquid chromatography with a polarized photometric detector was established. The polarized photometric detector was constructed with two polarizers mounted on both sides of the flow cell in a conventional photometric detector and can be easily used for the detection of optically active compound, such as l-menthol. This study was conducted with a newly developed split-cell assembly in order to increase the sensitivity. The characteristic of this method is the ability to determine optically active compounds selectively among the other coexisting materials and the pretreatment of the sample can be very simple or not required at all. The detection of l-menthol by this method is 0.5 microgram. A good agreement was shown between another commonly used GC method and the method described in this paper.

Chromatography, Gas↗

PubMed1998

Secondary correction of bilateral cleft lip deformity with simultaneous Abbé flap and nasal repair.

For secondary repair of a bilateral cleft lip deformity with a short columella and defective upper lip, simultaneous correction of the lip and nose is ideal. We perform a nasal repair through a bilateral reverse-U incision and columella elongation using the upper lip. An Abbé flap is then transferred to the upper lip defect. This procedure enables total reconstruction of characteristic bilateral cleft lip deformities in one stage. We have applied this method to 15 patients (9 males and 6 females) with an average age of 18.7 years. Although some patients need jaw surgery, all have been satisfied with the results.

Adolescent↗

PubMed1998

Neurite outgrowth of neuroblastoma cells overexpressing alpha and beta isoforms of Ca2+/calmodulin-dependent protein kinase II-effects of protein kinase inhibitors.

Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) is one of the most abundant protein kinases in the brain and has a broad substrate specificity [M.K. Bennett, N.E. Erondu, M.B. Kennedy, Purification and characterization of a calmodulin-dependent protein kinase that is highly concentrated in brain, J. Biol. Chem. 258 (1983) 12735-12744 [1]; J.R. Goldenring, B. Gonzalez, J.S. McGuire, Jr., R.J. DeLorenzo, Purification and characterization of a calmodulin-dependent kinase from rat brain cytosol able to phosphorylate tubulin and microtubule-associated proteins, J. Biol. Chem. 258 (1983) 12632-12640 [4]; M.B. Kennedy, P. Greengard, Two calcium/calmodulin-dependent protein kinases, which are highly concentrated in brain, phosphorylate protein I at distinct sites, Proc. Natl. Acad. Sci. U.S.A. 78 (1981) 1293-1297 [10]; T. Yamauchi, H. Fujisawa, Evidence for three distinct forms of calmodulin-dependent protein kinases from rat brain, FEBS Lett. 116 (1980) 141-144 [20]; T. Yamauchi, H. Fujisawa, Purification and characterization of the brain calmodulin-dependent protein kinase (kinase II), which is involved in the activation of tryptophan 5-monooxygenase, Eur. J. Biochem. 132 (1983) 15-21 [21]]. The alpha and beta isoforms of CaM kinase II are known to be expressed almost exclusively in the brain [P.I. Hanson, H. Schulman, Ca2+/calmodulin-dependent protein kinases, Annu. Rev. Biochem. 61 (1992) 559-601 [7]]. To elucidate the cellular function of CaM kinase II, we introduced cDNA of wild-type CaM kinase II alpha- or beta-isoform, and of mutant alpha-isoform (Ala-286 kinase) into two different types of neuroblastoma, Neuro2a (Nb2a) and NG108-15, thus generating cell lines stably producing elevated levels of these kinases. The mutant alpha-isoform is markedly suppressed in its autophosphorylation by replacement of Thr-286 with Ala [Y.-L. Fong, W.L. Taylor, A.R. Means, T.R. Soderling, Studies of the regulatory mechanism of Ca2+/calmodulin-dependent protein kinase II. Mutation of threonine 286 to alanine and aspartate, J. Biol. Chem. 264 (1989) 16759-16763 [3]; P.I. Hanson, M.S. Kapiloff, L.L. Lou, M.G. Rosenfeld, H. Schulman, Expression of a multifunctional Ca2+/calmodulin-dependent protein kinase and mutational analysis of its autoregulation, Neuron 3 (1989) 59-70 [6]; S. Ohsako, H. Nakazawa, S. Sekihara, A. Ikai, T. Yamauchi, Role of Threonine-286 as autophosphorylation site for appearance of Ca2+-independent activity of calmodulin-dependent protein kinase II alpha subunit, J. Biochem. 109 (1991) 137-143 [15]]. We provided evidence that CaM kinase II played a role in regulating neurite outgrowth and growth cone motility in these cells, and that the autophosphorylation is essential for the kinase to sufficiently exert its cellular function in vivo [Y. Goshima, S. Ohsako, T. Yamauchi, Overexpression of Ca2+/calmodulin-dependent protein kinase II in Neuro2a and NG108-15 neuroblastoma cell lines promotes neurite outgrowth and growth cone motility, J. Neurosci. 13 (1993) 559-567 [5]]. Neurite outgrowth was further stimulated by treatment with 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7) or chelerythrine, inhibitors of protein kinase C [T. Nomura, K. Kumatoriya, Y. Yoshimura, T. Yamauchi, Overexpression of alpha and beta isoforms of Ca2+/calmodulin-dependent protein kinase II in neuroblastoma cells-H-7 promotes neurite outgrowth, Brain Res. 766 (1997) 129-141 [14]]. The morphological change stimulated with protein kinase inhibitors was rapid and was greater in the beta than alpha cells. Some substrates of CaM kinase II related to neurite outgrowth were detected in cells overexpressing the kinase stimulated with H-7. These results suggest that CaM kinase II and protein kinase C play an important role in the control of cell change. (c) 1998 Elsevier Science B.V. All rights reserved.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1998

Sequential expression of bone morphogenetic protein, tumor necrosis factor, and their receptors in bone-forming reaction after mouse femoral marrow ablation.

Tumor necrosis factor-alpha (TNF-alpha) is considered a promoter of bone resorption and a suppressor of osteogenesis, whereas bone morphogenetic protein (BMP) is a promoter of bone formation. In the present study, the osteogenic potential of the medullary cavity after bone marrow ablation was evaluated in association with the pattern of BMP, bone morphogenetic protein receptor (BMPR), TNF-alpha, and tumor necrosis factor receptor (TNFR) expression. Immunostaining, in situ hybridization, and TRAP staining were performed following marrow ablation. By day 4, BMP-4 mRNA was detected by in situ hybridization in growing undifferentiated cells and, on day 7, the osteoblastic cells that covered abundant woven bone also showed evidence of BMP-4 expression. BMPR-IA and BMPR-II were immunolocalized from days 4 to 10 after ablation, and became negative on days 21 and 28. At 10 days postablation, osteoclasts were revealed by TRAP staining. TNF-alpha expression disappeared transiently after ablation and then reappeared on day 7, predominantly in osteoblastic cells. On days 7, 10, and 14, immunostaining for TNFR-I was observed in osteoblasts lining the woven bone and later disappeared. No evidence of TNFR-II staining was observed on osteoblastic cells throughout the reaction. From day 14, newly formed bone decreased in quantity and was replaced by hematopoietic cells and, by day 28, the bone marrow had regenerated to its original state. This study suggests that TNF-alpha is produced and secreted by the osteoblast and acts on these cells in an autocrine manner to suppress osteoblastic function. TNF-alpha may also play a role in the recruitment of osteoclasts because TRAP-positive osteoclasts appeared after TNF-alpha expression.

Acid Phosphatase↗

PubMed1998

The effects of gonadotropin-releasing hormone agonist on androstenedione production and follicular development during controlled ovarian hyperstimulation.

PURPOSE: We performed a prospective randomized study to assess the effects of a GnRH agonist (GnRH-a) on follicular development and steroidogenesis during controlled ovarian hyperstimulation (COH). METHODS: Patients undergoing in vitro fertilization (IVF) for tubal infertility received human menopausal gonadotropin (hMG) stimulation with or without the GnRH-a, buserelin, beginning in the midluteal phase of the prior cycle. We analyzed serum hormone levels, follicular development, and outcome of IVF. RESULTS: The mean number of retrieved oocytes was significantly greater, and the implantation rate per embryo was significantly higher, in the GnRH-a/hMG group (n = 101) than in the hMG-only group (n = 97). The concentration of androstenedione (A) and the A/estradiol ratio in the serum were significantly lower in the GnRH-a treatment group throughout the follicular phase. CONCLUSIONS: The concomitant use of GnRH-a during COH prevents atretic change of the follicles and enhances follicular development by reducing androgen accumulation, resulting in a higher developmental competence of the oocytes.

Adult↗

PubMed1998

Secondary repair of unilateral cleft lip nose deformity with bilateral reverse-U access incision.

Unilateral cleft lip is often accompanied by bilateral deformity. We use bilateral reverse-U incisions for the primary repair of unilateral cleft lip nose. This principle can also be applied to achieve symmetry of the nose in the secondary correction of the unilateral cleft lip nose. By the use of bilateral reverse-U access incisions and an inverted trapezoid suture between alar cartilages and nasal dome, it has become possible to achieve nasal symmetry and clearly defined alar groove. The surgical procedure is presented along with some representative cases.

Adolescent↗

PubMed1998

Primary repair of an incomplete unilateral cleft lip: avoiding an elongated lip and achieving a straight suture line.

The methods designed for the repair of a complete cleft lip should not be used to repair an incomplete cleft lip. This results too often in the postoperative drooping of the white lip on the affected side because in most incomplete cleft lips there is more tissue on the cleft side than in complete cleft lip. We present and discuss the refinements we made in our original technique for complete cleft lip in order to adapt it to incomplete cleft lip repair. The skin design at the white skin roll follows Cronin's method with an incision perpendicular to the vermilion border. The suture that pulls the edges of the angular incisions together pushes on the white skin roll caudally. This ensures that the peak of the Cupid's bow on the cleft side does not droop postoperatively. It also ensures that it does not take on an acute angle and that the vermilion border will be a continuous line without a break. We do not create a triangular flap at the vermilion border, but we raise a triangular flap at the alar base on the cleft side and advance it to the bottom of the columella. This creates the nostril sill and corrects the flared alar base. The resulting suture line is completely straight and runs along the philtral column. In this way, the postoperative elongation of the white lip on the cleft side can be prevented.

Cleft Lip↗

PubMed1998

Falloposcopic tuboplasty for bilateral tubal occlusion. A novel infertility treatment as an alternative for in-vitro fertilization?

The linear everting (LE) catheter has been developed to safely guide a Falloposcope into the entire length of Fallopian tube in order to observe the tubal lumen. It may also be useful therapeutically for the recanalization of occluded tubes. Fifty infertility patients who had been diagnosed with proximal, mid and distal tubal occlusion by hysterosalpingogram, Rubin test and hysteroscopic selective hydrotubation, were selected to undergo Falloposcopic tuboplasty (FT). Patients having hydrosalpinges were excluded from the study group. The total number of tubes treated was 102 during 53 FT procedures. On the basis of tubes attempted, the LE catheter successfully accessed 85.3% (87/102). A follow-up hysterosalpingogram was completed 1-3 months following the FT procedure, which revealed an overall patency rate of 79.4% (81/102). During FT, a high incidence of multiple adhesions was observed in the entire length of tubal lumen in patients having bilateral occlusions. To date, the total number of pregnancies following FT treatment is 11 over a follow-up period of 2 months to 3 years. FT has been established as a highly useful, less invasive and novel treatment for tubal infertility. This technique may be useful in selected patients with tubal infertility.

Catheterization↗

PubMed1998

Power and colour Doppler ultrasonography for the evaluation of the vasculature of the human corpus luteum.

We used power Doppler imaging to examine neovascularization in the corpus luteum (CL) in 12 healthy volunteers. We also investigated whether CL blood flow reflected luteal function. The ratio of the area of vessels in the CL to the area of a sectional plane at the maximum diameter of the CL observed by power Doppler (FA ratio) was used as a quantitative index of the vascularity of the CL. The pulsatility index (PI) was significantly lower in ovarian arteries with CL than without CL (P < 0.05). Changes in ovarian arterial and intra-luteal PI appeared to reflect physiological changes in the vasculature of the CL. There was no correlation between the volume of the CL or the FA ratio and the concentration of progesterone. The pattern of changes in the product of the FA ratio and the CL volume and in the progesterone concentration was similar. The progesterone concentration was positively correlated with this product (r = 0.74, P < 0.01). The product of the FA ratio and the CL volume plateaued during the mid- to late luteal phase, suggesting the presence of functional and structural luteolysis. These findings suggest that colour Doppler ultrasonography, including power Doppler imaging, can detect physiological changes in the blood flow of the ovary in the luteal phase, and may be a useful noninvasive tool for evaluating CL function.

Adult↗

PubMed1998

Functional role of focal adhesion kinase in the process of implantation.

The expression and function of focal adhesion kinase (FAK) in human decidual cells were investigated. This kinase is localized to focal adhesions in fibroblasts, and is phosphorylated on tyrosine in normal and src-transformed fibroblasts. Immunofluorescent staining revealed that the cultured decidual cells expressed high levels of FAK at the cell periphery. Double stainings for FAK and phosphotyrosine, FAK and talin, and FAK and beta1 integrin demonstrated that FAK co-localized with integrins in cellular focal adhesions. Mouse blastocysts became attached to cultured decidual cells after embryos hatched from the zona pellucida. The majority of hatched blastocysts attached to human decidual cells within 24 h of culture. Blastocysts attached to decidual cells exhibited extensive outgrowth after 48 h. Treatment of decidual cells with herbimycin A, a tyrosine kinase inhibitor, did not affect the rate of hatching or attachment of blastocysts. However, the outgrowth of embryos on the decidual cells was inhibited by the addition of herbimycin A in a dose-dependent manner, implying that blastocyst attachment and outgrowth are mediated by different mechanisms. This study suggests that tyrosine phosphorylation of FAK on decidual cells may be important in development and differentiation following attachment.

Adult↗