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H Nishida

Publications and source records attributed to H Nishida.

At least 19 recordsLinked to original sources
PubMed2002

[Dissecting aneurysm of ventricular septum following acute inferior myocardial infarction].

Dissecting aneurysm of the ventricular septum as a complication after myocardial infarction (MI) is very rare. The patient was a 70-year-old women who was diagnosed with acute inferior MI. Three months after MI, catheterization showed a left ventricular aneurysm of the inferior wall, and left-to-right ventricular shunt flow was detected in the aneurysm. Echocardiography showed that the inferior left ventricular free wall was aneurysmal and dissected from the septal wall. Nine months after MI, chronic heart failure was uncontrollable by medication. At surgery, a tear (5 mm long) in the dissecting aneurysm of the ventricular septum was found and closed directly using 2 felt patches, and aneurysmectomy was performed using felt strips. The postoperative course was uneventful and she has been free from any complication for over 1 year.

Aged↗
PubMed2001

Benefit of bilateral over single internal mammary artery grafts for multiple coronary artery bypass grafting.

BACKGROUND: The aim of this study was to evaluate the performance of bilateral internal mammary artery (BIMA) grafts in isolated CABG. METHODS AND RESULTS: Beginning in April 1985, elective primary multiple CABG for multivessel disease was performed in 1131 patients. The early and late results of 688 patients who received single internal mammary artery (SIMA) grafts and 443 patients who received BIMA grafts were compared (median follow-up, 6.15 years). Hospital mortality was not significantly different in the SIMA (0.9%) and BIMA (0.9%) groups. Graft patency was 97.3% in the BIMA group and 94.3% in the SIMA group (P<0.0001). The 7-year repeated CABG-free rate was significantly higher in the BIMA group (P=0.026). The 7-year new myocardial infarction-free rate in all patients tended to be higher in the BIMA group (P=0.06). The hazard ratio for all death or repeated CABG in patients with ejection fractions >0.4 and age <71 years was lower in the BIMA group (P=0.0499). CONCLUSIONS: Our data suggest that the use of BIMA grafts in patients with in situ coronary artery anastomoses achieves a significantly higher repeated CABG-free rate in all patients compared with the use of SIMA.

Adolescent↗
PubMed2001

Coronary artery bypass with only in situ bilateral internal thoracic arteries and right gastroepiploic artery.

BACKGROUND: With the rapid advance of catheter intervention, the direction taken by surgeons is not only to make conventional CABG less invasive but also to pursue better long-term results by using more arterial conduits. METHODS AND RESULTS: Between July 1989 and April 2000, 239 patients (218 men, 21 women) with a mean age of 59.7 (range 39 to 79) years underwent CABG with exclusive use of both internal thoracic arteries (ITAs) and the right gastroepiploic artery (RGEA). ITA grafts were harvested by using the skeletonization technique. Most patients (96%) had either triple-vessel or left main disease. Fifty percent of the patients were diabetic, and 16 were being treated with insulin. The left ventricular ejection fraction was </=40% in 46 patients (19%). Eleven patients (5%) had chronic renal failure and were on hemodialysis. Follow-up was completed in 235 patients (98%). Postoperative follow-up averaged 43 (range 1 to 129) months. Sequential grafting was performed in 64 patients, and the mean number of anastomoses was 3.3. One patient (0.4%) died of mediastinitis on the 53rd postoperative day. Graft patency was confirmed angiographically in 230 patients (96%) 2 to 3 weeks after surgery. The patency rate was 97.1% for the left ITA, 99.6% for the right ITA, and 95.5% for the RGEA. Five-year actuarial survival rate was 92.9%, and the cardiac death-free rate was 97.8%. CONCLUSIONS: Complete arterial grafting with both ITAs and RGEA was associated with minimal operative risk, a high early graft patency rate, and excellent long-term results.

Adult↗
PubMed2001

LL-Z1271alpha: an interleukin-1beta production inhibitor.

LL-Z1271alpha, a fungal metabolite, dose-dependently inhibited interleukin-1beta (IL-1beta) production in lipopolysaccharide (LPS)-stimulated human whole blood. Oral administration of LL-Z1271alpha to LPS-challenged mice caused significant lowering in the IL-1beta levels in peritoneal cavity. Data presented suggest that LL-Z1271alpha inhibits IL-1beta production by a novel mechanism as the inhibitory activity was not due to effects on caspase-1 (IL-1beta converting enzyme), the ATP-induced release mechanism or a lysosomotrophic effect.

Adenosine Triphosphate↗
PubMed2001

The BMP/CHORDIN antagonism controls sensory pigment cell specification and differentiation in the ascidian embryo.

We have investigated the role of the bone morphogenetic protein (BMP) pathway during neural tissue formation in the ascidian embryo. The orthologue of the BMP antagonist, chordin, was isolated from the ascidian Halocynthia roretzi. While both the expression pattern and the phenotype observed by overexpressing chordin or BMPb (the dpp-subclass BMP) do not suggest a role for these factors in neural induction, BMP/CHORDIN antagonism was found to affect neural patterning. Overexpression of BMPb induced ectopic sensory pigment cells in the brain lineages that do not normally form pigment cells and suppressed pressure organ formation within the brain. Reciprocally, overexpressing chordin suppressed pigment cell formation and induced ectopic pressure organ. We show that pigment cell formation occurs in three steps. (1) During cleavage stages ectodermal cells are neuralized by a vegetal signal that can be substituted by bFGF. (2) At the early gastrula stage, BMPb secreted from the lateral nerve cord blastomeres induces those neuralized blastomeres in close proximity to adopt a pigment cell fate. (3) At the tailbud stage, among these pigment cell precursors, BMPb induces the differentiation of specifically the anterior type of pigment cell, the otolith; while posteriorly, CHORDIN suppresses BMP activity and allows ocellus differentiation.

Animals↗
PubMed2001

Nuclear plasticity and timing mechanisms of the initiation of alkaline phosphatase expression in cytoplasm-transferred blastomeres of ascidians.

Egg cytoplasm containing endoderm determinants was transferred to presumptive-muscle or presumptive-epidermis blastomeres isolated from cleavage-stage embryos of the ascidian Halocynthia roretzi. We investigated three aspects of the expression of endoderm-specific alkaline phosphatase (ALP) activity. First, we examined whether ectopic ALP expression, an indication of ectopic endoderm formation, was promoted in cytoplasm-transferred blastomeres isolated at late-cleavage stage. The results showed that the cell fate was converted by the introduced cytoplasm, even in recipient blastomeres in which the cell fate was already restricted to muscle or epidermis, and in those where expression of the muscle- or epidermis-specific genes was already initiated. Next, we examined the formation of endoderm and other tissue in embryos by double staining for ALP and muscle- or epidermis-specific marker. Regions positive for ALP and positive for muscle or epidermis marker were mutually exclusive. These results suggested that muscle- or epidermis-specific genes that were already expressed in the recipient blastomeres were down-regulated in ectopically forming endoderm cells. This is evidence for nuclear plasticity during ascidian embryogenesis. In the last series of experiments, we investigated the timing of the appearance of ALP activity in cytoplasm-transferred embryos. In the partial embryos that were derived from various combination of recipient blastomeres and donor cytoplasm obtained from various staged eggs and embryos, the timing seemed to coincide with the time that starts when cell fusion for cytoplasmic transfer was done. Therefore, the clock that determines the timing of the initiation of ALP expression is likely to start at the moment of cell fusion. Several possible hypotheses for the timing mechanism are discussed.

Alkaline Phosphatase↗
PubMed2001

macho-1 encodes a localized mRNA in ascidian eggs that specifies muscle fate during embryogenesis.

Maternal information stored in particular regions of the egg cytoplasm has an important function in the determination of developmental fate during early animal development. Ascidians show mosaic development; such autonomous development has been taken as evidence that prelocalized ooplasmic factors specify tissue precursor cells during embryogenesis. Interest has been concentrated on the mechanisms underlying the formation of muscle cells in the tail, as yellow-coloured myoplasm in eggs is preferentially segregated into muscle-lineage blastomeres. Here we show that maternal messenger RNA of the macho-1 gene is a determinant of muscle fate in the ascidian Halocynthia roretzi. The macho-1 mRNA encodes a zinc-finger protein, and the mRNA is localized to the myoplasm of eggs. Depletion of the mRNA specifically resulted in the loss of primary muscle cells in the tail, as shown by the expression of muscle-specific molecular markers. The myoplasm of macho-1-deficient eggs lost its ability to promote muscle formation. Injection of synthesized macho-1 mRNA caused ectopic muscle formation in non-muscle-lineage cells. Our results indicate that macho-1 maybe both required and sufficient for specification of muscle fate, and that the mRNA is a genuine, localized muscle determinant.

Amino Acid Sequence↗
PubMed2001

Prognostic value of the colposcopic tumor size in stage IB squamous cervical cancer.

BACKGROUND AND OBJECTIVES: To determine the prognostic significance of the colposcopic tumor size in the management of cervical cancer. METHODS: Clinicopathological analysis was performed in 751 consecutive patients with stage IB squamous cervical cancer who were surgically treated in a single institute. The colposcopic tumor size was measured postoperatively on surgical specimens. Univariate and multivariate analyses were performed to determine the prognostic significance of various pathological factors. RESULTS: Among the pathological factors examined, lymph node metastasis, parametrial extension, deep stromal invasion, vessel permeation, endometrial extension, and colposcopic tumor size were found to be prognostic factors in univariate analysis, whereas multivariate analysis has confirmed that only three factors, i.e., lymph node metastasis, parametrial involvement, and colposcopic tumor size were independently associated with the disease-free interval. CONCLUSIONS: These results indicate that the colposcopic tumor size is an independent prognostic factor in squamous cervical cancer and can be used as an indicator of treatment options.

Adult↗
PubMed2001

Positive peritoneal cytology in endometrial cancer: enhancement of other prognostic indicators.

OBJECTIVE: The goal of this study was to investigate the prognostic significance of positive peritoneal cytology in endometrial cancer. METHODS: A clinicocytopathological study was performed in 534 patients with endometrial cancer to assess the prognostic value of positive peritoneal cytology. The study population was divided into three groups: a low-risk group (disease limited to the uterus, grade 1, and depth of invasion < or =1/2), a moderate-risk group (disease limited to the uterus, grade 2 or 3, and/or depth of invasion >1/2), and a high-risk group (extrauterine disease). In each group, disease-free survival was compared in the patients who were positive or negative for malignant cells. RESULTS: The overall incidence of positive peritoneal cytology was 22.3% (119/534). The 5-year disease-free survival of patients positive or negative for malignant cells was 98.1% versus 100% in the low-risk group (n = 250), 77.5% versus 91.3% in the moderate-risk group (n = 211), and 42.9% versus 72.1% in the high-risk group (n = 73). A significant difference was noted in the moderate-risk (P = 0.044) and high-risk (P = 0.015) groups, but not in the low-risk group (P = 0.56). CONCLUSIONS: Positive peritoneal cytology is not a negative prognostic indicator itself, but it potentiates other prognostic indicators for endometrial cancer. Our findings also suggest that patients with positive peritoneal cytology in the absence of other adverse prognostic factors do not need upstaging.

Adult↗
PubMed2001

Reconstruction of the left ventricle in a patient with cardiac hemangioma at the apex.

Cardiac hemangiomas in the left ventricle are extremely rare. A 34-year-old woman, without symptoms, with a diagnosis of cardiac tumor at the apex of the left ventricle was referred to us. The tumor was surgically resected, and the diagnosis was hemangioma. The Jatene technique, originally introduced for left ventricular aneurysmectomy was excellent for repair after resection of a cardiac tumor at the apex.

Adult↗
PubMed2001

Ostial stenosis of coronary arteries after complete replacement of aortic root using gelatin-resorcinol-formaldehyde glue.

Coronary ostial stenosis between an interposition graft and coronary artery is rare and fatal. A 46-year-old woman who had reconstruction of both coronary arteries using interposition grafts for type A acute dissecting aneurysm presented with acute chest pain. Emergent coronary artery bypass grafting was done with saphenous vein grafts. Inappropriate use of gelatin-resorcinol-formaldehyde glue can be associated with ostial stenosis in the long term. Transesophageal echocardiography is useful to diagnose ostial stenosis of the coronary arteries.

Aortic Valve↗
PubMed2001

International Child Care Practices Study: infant sleeping environment.

BACKGROUND: The International Child Care Practices Study (ICCPS) has collected descriptive data from 21 centres in 17 countries. In this report, data are presented on the infant sleeping environment with the main focus being sudden infant death syndrome (SIDS) risk factors (bedsharing and infant using a pillow) and protective factors (infant sharing a room with adult) that are not yet well established in the literature. METHODS: Using a standardised protocol, parents of infants were surveyed at birth by interview and at 3 months of age mainly by postal questionnaire. Centres were grouped according to geographic location. Also indicated was the level of SIDS awareness in the community, i.e. whether any campaigns or messages to "reduce the risks of SIDS" were available at the time of the survey. RESULTS: Birth interview data were available for 5488 individual families and 4656 (85%) returned questionnaires at 3 months. Rates of bedsharing varied considerably (2-88%) and it appeared to be more common in the samples with a lower awareness of SIDS, but not necessarily a high SIDS rate. Countries with higher rates of bedsharing appeared to have a greater proportion of infants bedsharing for a longer duration (>5 h). Rates of room sharing varied (58-100%) with some of the lowest rates noted in centres with a higher awareness of SIDS. Rates of pillow use ranged from 4% to 95%. CONCLUSIONS: It is likely that methods of bedsharing differ cross-culturally, and although further details were sought on different bedsharing practices, it was not possible to build up a composite picture of "typical" bedsharing practices in these different communities. These data highlight interesting patterns in child care in these diverse populations. Although these results should not be used to imply that any particular child care practice either increases or decreases the risk of SIDS, these findings should help to inject caution into the process of developing SIDS prevention campaigns for non-Western cultures.

Beds↗
PubMed2001

Hepatocellular carcinoma with blood supply from omental branches: treatment with transcatheter arterial embolization.

PURPOSE: To evaluate the usefulness of transcatheter arterial embolization (TAE) through the omental branch in the treatment of hepatocellular carcinoma (HCC) with blood supply from the omental branch. MATERIALS AND METHODS: Fifteen patients with HCC fed by the omental branch underwent TAE. All but one had previously undergone several therapies for HCC, including TAE. Three patients had intraperitoneal hemorrhage caused by ruptured HCC fed by the omental branch, and two necessitated emergency TAE. The technical success rate, therapeutic effect, and safety of TAE via the omental branch were evaluated. RESULTS: Twenty-six omental branches that fed HCC were observed angiographically. Attenuation or occlusion of the hepatic artery was observed in 80%. Nineteen omental branches (73%) could be successfully embolized. Hepatic hemostasis was achieved in all patients with ruptured HCC. Tumor recurred in 80% of patients who underwent successful TAE of the omental branch, and additional therapy was performed in six patients. Ten patients died after 2-26 months (mean, 8 mo). Five patients were alive for 3-13 months (mean, 7 mo). Severe complications were not observed in any patient. CONCLUSION: TAE of the omental branch is safe and has become technically feasible in almost all patients, but tumors frequently recur.

Aged↗
PubMed2001

Role of the FGF and MEK signaling pathway in the ascidian embryo.

In the ascidian embryo, a fibroblast growth factor (FGF)-like signal from presumptive endoderm blastomeres between the 32-cell and early 64-cell stages induces the formation of notochord and mesenchyme cells. However, it has not been known whether endogenous FGF signaling is involved in the process. Here it is shown that 64-cell embryos exhibit a marked increase in endogenous extracellular signal-regulated kinase (ERK/MAPK) activity. The increase in ERK activity was reduced by treatment with an FGF receptor 1 inhibitor, SU5402, and a MEK (ERK kinase/MAPKK) inhibitor, U0126. Both drugs blocked the formation of notochord and mesenchyme when embryos were treated at the 32-cell stage, but not at the 2- or 110-cell stages. The dominant-negative form of Ras also suppressed notochord and mesenchyme formation. Both inhibitors suppressed induction by exogenous basic FGF. These results suggest that the FGF signaling cascade is indeed necessary for the formation of notochord and mesenchyme cells during ascidian embryogenesis. It is also shown that FGF signaling is required for formation of the secondary notochord, secondary muscle and neural tissues, and at least ERK activity is necessary for the formation of trunk lateral cells and posterior endoderm. Therefore, FGF and MEK signaling are required for the formation of various tissues in the ascidian embryo.

Animals↗
PubMed2001

Validation of color Doppler EUS for azygos blood flow measurement in patients with cirrhosis: application to the acute hemodynamic effects of somatostatin, octreotide, or placebo.

BACKGROUND: Color Doppler EUS (CD-EUS) allows minimally invasive measurement of azygos blood flow (AzBF) in portal hypertension, but further validation of the method is needed. Because a limited number of patients has been studied, the acute hemodynamic effects of somatostatin and octreotide on AzBF and gastric mucosal perfusion are poorly defined in portal hypertension. METHODS: A double-blind hemodynamic study was designed to assess rapid changes in AzBF over a 60-minute period after intravenous administration of somatostatin, octreotide, and placebo in 30 stable patients with biopsy-proven cirrhosis. AzBF was measured by using both CD-EUS and the invasive thermal dilution technique in the first 10 patients (phase 1). Then, with CD-EUS alone, the hemodynamic study was extended to a further 20 patients (phase 2). In addition, gastric mucosal perfusion changes were assessed by using laser Doppler flowmetry at endoscopy. RESULTS: In phase 1, the 2 methods for AzBF measurement showed significant correlations both for baseline values (r = 0.685) and for AzBF changes over 60 minutes after drug administration (r = 0.733). In phase 2, a reduction was observed in AzBF 10 minutes after octreotide or somatostatin administration (-47% and -23%, p < 0.0001 vs. placebo, p = 0.058 vs. placebo, respectively). After 60 minutes of somatostatin infusion, AzBF increased 27% over placebo values (p < 0.04). Gastric mucosal perfusion was transiently reduced 5 minutes after octreotide or somatostatin (-21% and -32%, respectively, p < 0.02 vs. placebo). CONCLUSIONS: This is the first study to validate CD-EUS AzBF measurement with reference to the invasive thermodilution technique in cirrhosis. It confirmed the transient effects of somatostatin and octreotide on both AzBF and gastric mucosal perfusion. In addition, a significant rebound phenomenon after 60 minutes of continuous intravenous somatostatin infusion was observed.

Aged↗
PubMed2001

Evolution of amino acid biosynthesis and enzymes with broad substrate specificity.

UNLABELLED: I selected 82 proteins that were related to amino acid biosynthesis in the genome of Escherichia coli. I then searched the extensive sequence homology for each of the selected proteins from among the proteins of E.coli. The result showed that 30 proteins of the selected proteins had extensive sequence homology within the selected proteins, and 21 proteins had extensive sequence homology to proteins outside the selected proteins. In addition, the enzymes with broad substrate specificity play an important role in the amino acid biosynthesis. I demonstrate here that some substrate-specific enzymes evolved from an ancestor enzyme with broad substrate specificity. CONTACT: hnishida@iam.u-tokyo.ac.jp

Amino Acids↗
PubMed2001

Distribution of genes for lysine biosynthesis through the aminoadipate pathway among prokaryotic genomes.

Deinococcus radioduranshas homologous genes to the genes which from the Thermus: thermophilus gene cluster for lysine biosynthesis. Interestingly, those genes are clustered in Thermus, nevertheless they are scattered in Deinococcus. A similar gene cluster has only been found in Pyrococcus However, the phylogenetic analyses indicated that the deduced gene products from Deinococcus were the most closely related to the proteins encoded in the Thermus gene cluster for lysine biosynthesis. Therefore, those genes had not been transferred horizontally between Pyrococcus and Thermus. It is strongly suggested that a common ancestor of Deinococcus and Thermus possessed the genes for lysine biosynthesis through the aminoadipate pathway. These had been clustered through the evolution of Thermus or had been scattered from the gene cluster through the evolution of Deinococcus. In addition, I showed that LysW and its homologues were specialized proteins for the prokaryotic lysine biosynthesis through the aminoadipate pathway.

Amino Acid Sequence↗