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Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 199 records · Page 11Linked to original sources
PubMed1997

Prophylactic laparoscopic ovarian ablation for premenopausal breast cancer: medical and economic efficacy.

Worldwide analysis showed a highly significant reduction in the annual rates both of recurrence and of death produced by ovarian ablation. We examined the safety, efficacy, and cost-effectiveness of prophylactic laparoscopic oophorectomy for premenopausal breast cancer. Prophylactic laparoscopic oophorectomy was attempted in 15 selected premenopausal patients with breast cancer. After mastectomy, these patients had laparoscopic ovarian ablation as treatment for breast carcinoma with positive estrogen receptors. To evaluate the economic impact of laparoscopic oophorectomy, comparisons were made between patients treated laparoscopically and those treated with conventional surgery, chemotherapy, and hormonal therapy. The average time required for laparoscopic bilateral oophorectomy was 44 min. Oral intake was resumed the next morning, and the patients were discharged 3 days after surgery. No limitation on physical activity and no complications were required during postoperative days. There was no reduction in the overall costs of laparoscopic surgery and conventional surgery in Japan. The cost of one year's supply of tamoxifen was equivalent to the overall cost of surgical oophorectomy. From medical and economic viewpoints, we conclude that laparoscopic ovarian ablation should be considered an alternative to adjuvant chemotherapy in premenopausal women.

Activities of Daily Living↗
PubMed1997

Operative results of thoracoabdominal repair for chronic type B aortic dissection.

From January 1991 to May 1994, we have operated on 15 cases of Type B aortic dissection. In 10 of these patients, thoracoabdominal repair was performed. According to Crawford's classification, 2 patients fell into Type I, 6 patients into Type II, and 2 patients into Type III. The aneurysms were exposed through a left thoracotomy extending into the retroperitoneum with the hemidiaphragm divided circumferentially. The operations were performed under femoro-femoral partial cardiopulmonary bypass. In 6 of these cases selective perfusion of the visceral branches was used. The celiac axis was reconstructed in 10 patients, superior mesenteric artery in 9, right renal artery in 7, left renal artery in 6. Abdominal vessels were reconstructed by the "inclusion" technique described by Crawford in 2 patients, by "beveling" the distal prosthetic end in 6 and by the "interposition" technique in 4 patients. Vessels arising from the false lumen were reconstructed by the "interposition" technique. To prevent paraplegia, the evoked spinal cord potentials by direct stimulation of the cord (ESPs-dsc) were monitored perioperatively and the aneurysms were repaired sequentially in segments. In all patients except 2 with Crawford type III aneurysms, spinal cord ischemia was detected by ESPs-dsc. In 7 of these patients, 2 to 8 pairs of intercostal/lumbar arteries (I/L aa.) that arose from the "responsible" aortic segment were reconstructed. Reconstruction techniques included the "inclusion" technique in 2 patients, the "beveling" technique in 1, the "interposition" technique in 1 and the "on lay grafting" technique in 3 patients. One hospital death occurred in a patient who had chronic renal insufficiency and liver cirrhosis preoperatively. Spinal cord injury occurred in 5 patients, including 4 paraparesis and 1 delayed-onset paraplegia. In 2 of these patients, responsible I/L aa., were not reconstructed correctly despite ESPs changes, and injury might have been prevented if reconstruction of the "responsible" arteries had been performed. Thoracoabdominal repair for chronic Type B aortic dissection could be performed safely with an acceptable mortality rate. Spinal cord injury remains an unsolved problem.

Aortic Dissection↗
PubMed1997

The reliability of evoked spinal cord potentials elicited by direct stimulation of the cord as a monitor of spinal cord ischemia during temporary occlusion of the thoracic aorta.

Paraplegia is a severe and disastrous complication of operations on the thoracic aorta. For preventing this complication, we employed evoked spinal cord potentials elicited by direct stimulation of the cord (ESPs-dsc) during operations on 83 patients with various aortic lesions (37 dissecting and 46 cases of nondissecting aneurysms, 35 descending and 48 thoracoabdominal aortic aneurysms). All of the patients had some form of circulatory adjunct during aortic cross-clamping. Of the 83 patients, three had "immediate" paraparesis and five had "immediate" paraplegia, whereas three other patients had "delayed" paraplegia. During operation, four types of ESPs-dsc response pattern were observed: (1) no change (n = 57), (2) change with return (n = 15), (3) change with inconsistent return (n = 6), (4) change without return (n = 5). "Delayed" paraplegia occurred in two patients with "no change" and "change with return" response (3%), "immediate" paralysis occurred in three and "delayed" paraplegia occurred in one of those with "change with inconsistent return" response (67%), and all of those with "change with inconsistent return" response (67%), and all of those with "change without return" response developed "immediate" paraplegia (100%). We conclude that intraoperative monitoring of spinal cord function utilizing ESPs-dsc is a good indicator of spinal cord ischemia and we can improve the outcome according to its changes.

Aorta, Thoracic↗
PubMed1997

[Regulation of growth and survival of germ cells].

Growth and survival of germ cells seem to be strictly regulated by a number of environmental and intrinsic factors. One of the most important factor is Steel factor, which is necessary not only for the rapid proliferation and survival of primordial germ cells(PGCs) in embryos, but also for the development of spermatogonia and oocytes in adult gonads. Other growth factors which are linked to different signaling pathway collaboratively support PGC growth with Stecl factor. Therefore, synergistic action of different signal transduction pathway seems to be important for PGC growth. In adult testis, a large part of spermatogonia undergoes cell death, but the physiological significance and molecular mechanisms of this process are largely unknown. We have investigated the effect of misexpressing Bcl-2 in spermatogonia in transgenic mice. And we found that ectopically expressed Bcl-2 in spermatogonia inhibited their normal apoptosis. In addition abnormally accumulated spermatogonia fail to undergo further differentiation and survival, and they were just deleted from testis. These results indicate that spermatogonial apoptosis is part of the normal program of mammalian spermatogenesis and is regulated by a pathway affected by Bcl-2.

Adult↗
PubMed1997

Mycotic aneurysm of the bilateral tibioperoneal trunks associated with bacterial endocarditis: a case report.

Since antibiotics have been widely used in the treatment of bacterial endocarditis, mycotic aneurysms caused by septic emboli have become extremely rare. We report the case of a 34-year-old man who had mycotic aneurysms in the tibioperoneal trunks of both legs six weeks after he had a mitral valve replacement due to Streptococcus viridans endocarditis. Color Doppler sonography was used to diagnose pseudoaneurysms in both legs. Surgical treatment included the closures of the orifices of both aneurysms in both legs and arterial reconstructions were not required. In the literature, however, the location of mycotic aneurysms in peripheral arteries related to endocarditis were usually reported to be in the upper extremities or femoral arteries. Thus, we present the extremely rare case of mycotic aneurysms because the aneurysms occurred in the infrapopliteal vessel and developed in both legs.

Adult↗
PubMed1997

[Creutzfeldt-Jakob disease with a widespread presence of kuru-type plaques after cadaveric dural graft replacement. An autopsy case].

A case of Creutzfeldt-Jakob disease (CJD) is reported in a 48-year-old woman who had received a cadaveric dural graft after a clipping procedure of a cerebral artery aneurysm in September 1985. In November 1994, she noticed unsteady gait and blurred vision at first. She successively developed ataxic gait, dementia and myoclonus, and became mute. Serial CT scans revealed no abnormal findings, and serial EEGs showed diffuse slow activity without periodic discharge. The patient died in March 1996, 17 months after the initial symptoms. A brain autopsy demonstrated extensive spongiform degeneration in the cerebral neocortex, thalamus, striatum, and cerebellum especially in the granular layer, with associated astrocytosis and marked neuronal loss. Immunohistochemically, PrP plaques, so called kuru-type plaques, were extensively distributed throughout the cerebrum and cerebellum. Moreover, some of these plaques resembled "florid" plaques, which were surrounded by a zone of spongiform change. The PrP gene analysis of her blood and brain tissue revealed no mutations with homozygosity, Met/Met, at codon 129. The unusual features of this case, that is the absence of PSD on EEG and the widespread presence of kuru-type plaques including "florid" plaques, may be similar to the features of "new variant" CJD.

Cadaver↗
PubMed1996

A receptor tyrosine kinase, Sky, and its ligand Gas 6 are expressed in gonads and support primordial germ cell growth or survival in culture.

Although a number of growth factors and their receptors are involved in the proliferation and differentiation of primordial germ cells (PGCs), the only factor that has been shown to be active in vivo is Steel factor, a ligand for c-Kit. To identify new growth factor receptors that may be required for PGCs function in vivo, we used an reverse transcription-polymerase chain reaction-based strategy to screen for protein kinase genes expressed in PGC-derived embryonic germ cells. We report here that one such gene encoding the receptor tyrosine kinase, Sky, is expressed in both PGCs and their supporting cells in male genital ridges after 11.5 dpc. Interestingly, Sky expression was not detected in female genital ridges, although transcripts were detected in supporting cells in the developing ovary at later stages. Gas 6, a ligand for Sky, was also expressed in interstitial cells which surround Sky positive cells in genital ridges, and, in addition, it supported PGC growth or survival in culture. After birth, Sky expression in testis was restricted to Sertoli cells, and Gas 6 was detected around peritubular cells and Leydig cells. These results suggest that Gas 6-Sky signaling plays a role in PGC growth, sexual differentiation, and Sertoli cell functions in vivo. Sky expression in Sertoli cells diminished by 3 weeks of age, when haploid germ cells first appear. On the other hand, the expression in Sertoli cells was markedly upregulated in the testis of germ cell-deficient W/Wv and jsd/jsd mice. The results suggest that signals from differentiated germ cells suppress Sky gene expression in Sertoli cells. High-resolution chromosomal mapping of Sky is also reported.

Animals↗
PubMed1996

Dominant mutant alleles of yeast protein kinase gene CDC15 suppress the lte1 defect in termination of M phase and genetically interact with CDC14.

LTE1 encodes a homolog of GDP-GTP exchange factors for the Ras superfamily and is required at low temperatures for cell cycle progression at the stage of the termination of M phase in Saccharomyces cerevisiae. We isolated extragenic suppressors which suppress the cold sensitivity of lte1 cells and confer a temperature-sensitive phenotype on cells. Cells mutant for the suppressor alone were arrested at telophase at non-permissive temperatures and the terminal phenotype was almost identical to that of lte1 cells at non-permissive temperatures. Genetic analysis revealed that the suppressor is allelic to CDC15, which encodes a protein kinase. The cdc15 mutations thus isolated were recessive with regard to the temperature-sensitive phenotype and were dominant with respect to suppression of lte1. We isolated CDC14 as a low-copy-number suppressor of cdc15-rlt1. CDC14 encodes a phosphotyrosine phosphatase (PTPase) and is essential for termination of M phase. An extra copy of CDC14 suppressed the temperature sensitivity of cdc15-rlt1 cells, but not that of cdc15-1 cells. In addition, some residues that are essential for the CDC14 PTPase activity were found to be non-essential for the suppression. These results strongly indicate that Cdc14 possesses dual functions; PTPase activity is needed for one function but not for the other. We postulate that the cooperative action of Cdc14 and Cdc15 plays an essential role in the termination of M phase.

Alleles↗
PubMed1996

Regulation of energy metabolism by interleukin-1beta, but not by interleukin-6, is mediated by nitric oxide in primary cultured rat hepatocytes.

The effects of inflammatory cytokines (interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha) on energy metabolism were studied in primary cultured rat hepatocytes. Adenine nucleotide (ATP, ADP, and AMP) content, lactate production, the ketone body ratio (acetoacetate/beta-hydroxybutyrate) reflecting the liver mitochondrial redox state (NAD+/NADH), and nitric oxide formation were measured. Insulin increased ATP content in hepatocytes and had a maximal effect after 8-12 h of culture. Both interleukin-1beta and interleukin-6, but not tumor necrosis factor-alpha, significantly inhibited the ATP increase time- and dose-dependently. Interleukin-1beta and interleukin-6 also stimulated lactate production. During the same period, interleukin-1beta but not interleukin-6 decreased the ketone body ratio. Furthermore, interleukin-1beta markedly stimulated nitric oxide formation in hepatocytes, and this increase was blocked by NG-monomethyl-L-arginine (a nitric oxide synthase inhibitor) and by interleukin-1 receptor antagonist. NG-monomethyl-L-arginine reversed inhibition of the ATP increase, decrease in the ketone body ratio, and increase in lactate production, which were induced by interleukin-1beta. Interleukin-1 receptor antagonist completely abolished all of the effects induced by interleukin-1beta. These results demonstrated that interleukin-1beta and interleukin-6 affect the insulin-induced energy metabolism in rat hepatocytes by different mechanisms. Specifically, interleukin-1beta inhibits ATP synthesis by causing the mitochondrial dysfunction, a process which may be mediated by nitric oxide.

Adenine Nucleotides↗
PubMed1996

A novel serine/threonine kinase gene, Gek1, is expressed in meiotic testicular germ cells and primordial germ cells.

We have isolated a novel serine/ threonine kinase gene designated Gek1 from mouse primordial germ cell-derived embryonic germ cell. Gek1 is preferentially expressed in meiotic testicular germ cells and primordial germ cells. Gek1 mRNA is also detected in several other tissues, including hematopoietic organs in adult mice and central nervous system in embryos. The Gek1 cDNA encodes a protein with the consensus sequence of the catalytic domain of protein kinases in its N-terminal region. The deduced amino acid sequence of Gek1 in the kinase domain is related to those encoded by the Saccharomyces cerevisiae STE20, CDC15, and Drosophila melanogaster ninaC. The patterns of expression and the structural features of Gek1 suggest that the gene product is involved in signal transduction or nuclear division of germ cells and other proliferating cells. We also show that Gek1 locates on chromosome 11, near the wr locus, showing neuronal and reproductive defects.

Amino Acid Sequence↗
PubMed1996

Sustained ventricular tachycardias associated with myotonic dystrophy.

Patients with myotonic dystrophy are reported to have a higher frequency of sudden death than the general population. Although causes of sudden death in myotonic dystrophy are suggested to be due to conduction of defects progressing, the HV interval cannot predict whether conduction system disease would develop or progress. We report two cases of myotonic dystrophy complicated with sustained monomorphic ventricular tachycardias (VT), which can cause sudden death. In Case No. 1, although the patient was treated successfully for sustained VT with verapamil in electrophysiologic studies, another sustained VT was confirmed 2 years later. In Case No. 2, the patient showed decreased left ventricular ejection fraction and late potentials, and induced sustained VT that was identical to clinically documented VT. Although VT is believed to be rare in patients with myotonic dystrophy, these cases suggest that VT is a possible cause of sudden death.

Adult↗
PubMed1996

Detection of antibodies to Borrelia species among patients with confirmed sarcoidosis in a region where Lyme disease is nonendemic.

BACKGROUND: Lyme disease is a multisystemic disorder caused by the spirochete Borrelia burgdorferi, while sarcoidosis is a multisystemic granulomatous disease of unknown etiology. The purpose of this study was to evaluate the relationship between Lyme disease and sarcoidosis. METHODS: We examined the seroprevalence of antibody to Borellia species in patients with sarcoidosis. We performed the enzyme-linked immunosorbent assay, using three Japanese Borrelia species in addition to B. burgdorferi, and dotblot analysis using purified Borrelia-specific proteins in 38 patients with histopathologically confirmed sarcoidosis and 80 healthy controls. RESULTS: Two patients (5.3%) were positive for antibodies to Borrelia species according to one or both assays, and one (1.2%) healthy control was positive. In both patients it was suspected that Borrelia infection had developed prior to the development of sarcoidosis. CONCLUSION: Borrelia species were thought not to be responsible for the development of sarcoidosis in a nonendemic region in Japan. Since clinical manifestations of Lyme disease share certain similarities with those seen in sarcoidosis, ophthalmologists should be aware of the need to differentiate between the two diseases and the need for prompt treatment in each case.

Adult↗
PubMed1996

A recurrent 1992delCT mutation of the type X collagen gene in a Japanese patient with Schmid metaphyseal chondrodysplasia.

We report here a recurrent frameshift mutation within the carboxyl-terminal noncollagenous domain coding region of the type X collagen gene (COL10A1) in a Japanese patient with Schmid metaphyseal chondrodysplasia. The mutation involves deletion of a CT dinucleotide from position 1992 (1992delCT), and produces a frameshift which creates a premature termination codon close to the site of the deletion. The predicted length of the mutant polypeptide is 664 amino acids, which is shorter than the wild type polypeptide (680 amino acids). A 1992delCT mutation of COL10A1 has been previously reported in one family. The independent occurrence of de novo mutation of this specific dinucleotide repeat suggests that this region is a possible mutational hot spot on COL10A1.

Asian People↗
PubMed1996

Somatosensory afferent inputs release 5-HT and NA from the spinal cord.

Endogenous serotonin (5-HT) and noradrenaline (NA) release by somatosensory afferent inputs was investigated at the level of the spinal cord using in vivo microdialysis technique combined with high performance liquid chromatography and electrochemical detection (HPLC-ECD). Selective stimulation of large myelinated A beta afferent fibers significantly increased 5-HT release to 151.1 +/- 10.1% of the control, but did not affect NA release. However, selective stimulation of small myelinated A delta fibers released NA rather than 5-HT. The NA level enhanced to 128.8 +/- 6.4% of the control after A delta fibers were stimulated with the intensity of 6 times threshold. Stimulation of unmyelinated C fibers unavoidably excited the A beta and A delta afferent fibers, causing both 5-HT and NA release from the spinal cord. The results suggest that both innocuous and noxious information may activate serotonergic descending pathways. The noradrenergic descending pathways are only triggered by noxious inputs transmitted by small afferent fibers.

Afferent Pathways↗