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T Baba

Publications and source records attributed to T Baba.

At least 91 records · Page 5Linked to original sources
PubMed2000

Enhanced secretion of cardiac hepatocyte growth factor from an infarct region is associated with less severe ventricular enlargement and improved cardiac function.

OBJECTIVES: We hypothesized that the hepatocyte growth factor (HGF) may play a cardioprotective role in human myocardial infarction (MI). BACKGROUND: The HGF is a novel, multifunctional growth factor implicated in wound healing, angiogenesis and promotion of cell survival. Recent animal studies have demonstrated the existence of an HGF system in the heart, where it is activated in response to myocardial ischemia and reperfusion. METHODS: We studied 40 patients with acute myocardial infarction (AMI), who underwent coronary reperfusion therapy upon admission. Approximately four weeks later, left ventricular (LV) catheterization was repeated to determine the LV ejection fraction (EF), end-diastolic volume index (EDVI) and pressure (EDP). The levels of HGF and brain natriuretic peptide (BNP) were measured by collecting blood samples from cardiac veins draining the infarcted region (MI region) and those draining the noninfarcted region (non-MI region). The ratio of the HGF level in the MI region to that in the non-MI region (= MI/non-MI ratio) was calculated in each patient as an index of the MI-related HGF secretion. The MI/non-MI ratio for BNP was also calculated. RESULTS: The MI/non-MI ratio for HGF correlated inversely with LVEDP (r = -0.644, p < 0.0001) and LVEDVI (r = -0.843, p < 0.0001) and positively with LVEF (r = 0.763, p < 0.0001). These correlations were completely opposite in direction from those for BNP and LVEDP (r = 0.678, p < 0.0001), LVEDVI (r = 0.783, p < 0.0001) and LVEF (r = -0.805, p < 0.0001). These findings indicate that cardiac HGF acts in contrast to BNP, a biochemical marker for the development of LV remodeling. CONCLUSIONS: Enhanced secretion of cardiac HGF from the MI region is associated with an attenuation of ventricular enlargement and an improvement in cardiac function. The HGF system may modulate the process of ventricular remodeling and thus have important clinical implications.

Biomarkers↗
PubMed2000

Evaluation of balloon-occluded hepatic venography with carbon dioxide for portography and correlation between retrograde portogram and liver function in patients with liver cirrhosis.

Background/Aim: Hepatic venography with a positive-contrast medium has been reported as a method for evaluating liver disease. However, the contrast medium used in this method provides insufficient portal vein observation and may cause severe liver injuries. Carbon dioxide (CO(2)), a negative-contrast medium, may be able to depict the portal vein system with minimal hepatic toxicity. The aim of this study was to evaluate the usefulness and side-effects of balloon-occluded hepatic venography with CO(2) (CO(2) venography) and to evaluate the correlation between retrograde portogram and liver function in patients with cirrhosis. Subjects and methods: The subjects consisted of 23 biopsy-proven cirrhotic patients (male:female, 16:7; age, 58+/-12 years, range 34-80). The causes of cirrhosis were alcohol intake in ten, HCV infection in ten, HBV infection in one, primary biliary cirrhosis in one and Budd-Chiari syndrome in one. Of these patients, six were complicated with hepatocellular carcinoma (HCC). CO(2) venography was performed with an occlusion balloon catheter, and 25 ml of CO(2) was infused. CO(2) portograms were scored as follows: 0, no visualization of portal veins; 1, visualization of peripheral portal branches; 2, unilateral first portal branch; 3, bilateral first portal branches; 4, main portal vein; 5, left gastric vein, superior mesenteric vein and splenic vein. Hepatic venous pressure gradient (HVPG), cardiac functions, biochemical analysis, blood gas analysis and oxygen (O(2)) saturation monitoring were measured simultaneously. Arterio-portography was also performed. To evaluate the usefulness of CO(2) venography in patients with HCC accompanied by portal vein tumor thrombus (PVTT), three patients were also examined. Results: No significant changes in ALT, AST, O(2) saturation or blood gas data were observed after CO(2) venography. A statistically significant positive correlation was observed between CO(2) portogram scores and Child-Pugh scores (r=0.68, P=0.003). The correlations between CO(2) portogram scores and HVPG, and the forms of gastroesophageal varices in patients without PVTT and major shunts were not significant. The CO(2) portogram score was significantly higher in patients with alcoholic liver cirrhosis than in those with HCV-positive cirrhosis (P=0.04). Cavernous transformation and peripheral portal branches were demonstrated in patients with HCC accompanied by PVTT. These findings could not be observed by arterio-portography. Conclusion: CO(2) venography to obtain retrograde portogram is a safe and useful method for evaluating the portal vein system and liver function in patients with liver cirrhosis.

Journal Article↗
PubMed2000

Stimulatory effect of regucalcin on proteolytic activity is impaired in the kidney cortex cytosol of rats with saline ingestion.

The effect of regucalcin (RC) on neutral proteolytic activity in the cytosol of rat kidney cortex was investigated. Proteolytic activity was significantly increased by the presence of RC (0.01-0.10 microM) in the enzyme reaction mixture. This increase was completely abolished by the addition of anti-RC monoclonal antibody (150 ng/ml). When the renal cortex cytosol was incubated without RC addition, the degradation of globin of substrate was demonstrated by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. This degradation was clearly inhibited by the addition of anti-RC antibody (150 ng/ml), indicating that protein degradation results partly from the cytosolic endogenous RC. Meanwhile, proteolytic activity was significantly decreased in the renal cortex cytosol of rats with saline ingestion for 2, 7, and 14 days. The effect of RC (0.1 microM) in increasing proteolytic activity was weakened in the kidney cortex cytosol of saline-ingested rats. The present study suggests that endogenous RC plays a role in the activation of proteases in the renal cortex cytosol, and that the RC effect is impaired in saline-ingested rats.

Animals↗
PubMed2000

Stem cell factor and/or endothelin-3 dependent immortal melanoblast and melanocyte populations derived from mouse neural crest cells.

Stem cell factor (SCF) and endothelin-3 (ET3) are both necessary for melanocyte development. In order to obtain immortal cell populations of melanoblasts that can survive without feeder cells, we first obtained an immortal cell population of neural crest cells (NCCs) from Sl/+ and +/+ mice of strain WB by incubating with a culture medium supplemented with SCF and ET3, and then we designated them as NCC-SE3 cells. NCC-SE3 cells were bipolar, polygonal, or round in shape and possessed melanosomes of stages I-III (mainly stage I). They were positive to dihydroxyphenylalanine (DOPA) reaction and expressed KIT (a receptor tyrosine kinase), tyrosinase, tyrosinase-related protein-1 (TRP1), tyrosinase-related protein-2 (TRP2), and endothelin-B receptor (ETRB) as determined by immunostaining. We next cultured NCC-SE3 cells by changing culture medium from the one supplemented with SCF + ET3 to the one supplemented with SCF or ET3. NCC-SE3 cells cultured with ET3 alone, designated as NCC-E3 cells, were bipolar in shape and had mainly stage II melanosomes and expressed the same proteins as did NCC-SE3 cells. However, NCC-SE3 cells cultured with SCF alone, designated as NCC-S4.1 cells, were polygonal in shape and had mainly stage I melanosomes. They are thought to be more immature because they were positive to KIT, TRP1, and TRP2, but not to ETR(B), tyrosinase, and DOPA reaction. When 12-O-tetradecanoylphorbol 13-acetate and cholera toxin were added to the culture medium, NCC-S4.1 cells changed shape from polygonal to bipolar and became DOPA-positive. This suggests that NCC-S4.1 cells are melanoblasts that have the potential to differentiate into melanocytes. These cell populations will be extremely useful to study factors that affect melanocyte development and melanogenesis.

Animals↗
PubMed2000

A case of unilateral dermatomal cavernous haemangiomatosis.

We report a 39-year-old man with unilateral dermatomal cavernous haemangiomatosis (UDCH). Clinically, three haemangiomas were unilaterally distributed in the C6 dermatome. Histologically, these haemangiomas were distinct from routine cavernous haemangioma in that hyperplasia of smooth muscle cells on the vascular wall was observed, and electron microscopy showed that smooth muscle cells contained myofilaments and a crystal-like structure in the endothelial cells. This is distinct from Weibel-Palade bodies, which are rod-shaped cytoplasmic organelles measuring approximately 0.1 microm in diameter with a parallel linear structure. In UDCH, the haemangiomas occur only in the skin. They are clinically and histologically similar to those of blue rubber bleb naevus syndrome (BRBNS), but in BRBNS there are multiple haemangiomas in the digestive tract and other organs. UDCH is distinct from Maffucci syndrome in that enchondromata and malignant tumours are absent. To our knowledge, this is the second case of UDCH reported in the literature.

Adult↗
PubMed2000

A novel RNA motif that binds efficiently and specifically to the Ttat protein of HIV and inhibits the trans-activation by Tat of transcription in vitro and in vivo.

BACKGROUND: To find a novel RNA that would bind efficiently and specifically to Tat protein but not to other cellular factors, we used an in vitro selection method and isolated a novel aptamer RNATat, a 37-mer RNA oligomer, that binds efficiently to the Tat protein of HIV-1. In the present study, we analysed various properties of aptamer RNATat, including binding kinetics, identification of functional groups for Tat binding, and inhibition of Tat function. RESULTS: The binding affinity of the isolated aptamer RNATat to Tat-1 was 133 times higher than that of authentic TAR-1 RNA. RNATat is composed of inverted repeats of two TAR-like motifs, and even though RNATat had two Tat-binding core elements, the interaction with Tat took place at a molar ratio of 1 : 1. Several functional groups of aptamer RNATat responsible for Tat binding were identified. The selected aptamer RNATat competed effectively for binding to Tat even in the presence of a large excess of TAR-1 or TAR-2 RNA in vitro, and specifically prevented Tat-dependent trans-activation both in vitro and in vivo. CONCLUSIONS: Our results indicate that a novel aptamer, RNATat, retained strong affinity for Tat even in the presence of a large excess of HIV TAR. RNATat binds efficiently to Tat proteins or peptides derived from either HIV-1 or HIV-2. Unlike TAR RNA, RNATat affinity does not depend upon cellular proteins such as cyclin T1, thus RNATat has the potential for use as a molecular recognition element in biosensors.

Base Sequence↗
PubMed2000

Molecular beacon aptamer fluoresces in the presence of Tat protein of HIV-1.

BACKGROUND: We reported an aptamer, RNATat that binds to the Tat protein of HIV with two orders of magnitude greater (133-fold) affinity over the TAR RNA of HIV-1 and specifically inhibits the Tat-dependent trans-activation of transcription, both in vitro and in vivo (demonstrated in the accompanying article, Yamamoto et al., this issue pp. 371-388). We now report the use of aptamer-derived oligomers to analyze the Tat of HIV and the possible applications of such constructs in the field of biosensors. RESULTS: To make new molecular beacon, we constructed two RNA oligomers that derived from RNATat. To one of the split RNA oligomers that forms a hairpin structure, the fluorophore and quencher were attached at the 5'- and 3'-ends, respectively. Specifically in the presence of Tat or its peptides, but not in the presence of other RNA binding proteins, the two oligomers undergo a conformational change to form a duplex that leads to relieving of fluorophore from the quencher, and thus a significant enhancement of the fluorescence of fluorescein was observed. CONCLUSION: A novel strategy for exploiting aptamers in the analysis of Tat (analyte) has been described. A similar strategy could be used to study other analytes such as proteins and small molecules. In addition, the molecular beacon aptamer requires half the length of target sequence (eight nucleotides) in comparison with molecular beacons. Thus, it is conceivable that we could insert an analyte-binding site into molecular beacons to convert them to signalling beacons.

Biosensing Techniques↗
PubMed2000

FRL1 is required for petal and sepal development in Arabidopsis.

A novel flower mutant, frl1 (frill 1) was isolated in Arabidopsis thaliana. The frl1 mutant has serrated petals and sepals but the other floral and vegetative organs appear to be normal. To analyse the role of the FRL1 gene, morphological, cytological and double mutant analyses were carried out. The frl1 flower had broader petals and sepals as compared with the wild-type. The distal region of frl1 petals contained fewer epidermal cells but their size was variable and generally larger than that in the wild-type. However, no significant difference was found in the basal region. Observations of the early petal development revealed that the morphology of the developing frl1 petal was normal until the middle of stage 9, but the frl1 phenotype became apparent in stages later than 10. Furthermore, larger nuclei with varied sizes were observed in the distal region of frl1 petals, but not in this region in wild-type petals. This strongly suggests that abnormal endo-reduplication had occurred. These observations indicate that the frl1 mutation affects the number of cell divisions and the subsequent cell expansion during the late stage of petal lamina formation, and that FRL1 might be maintaining the mitotic state or suppressing the transition to the endo-reduplication cycle. Double mutants with the homeotic mutants apetala3-1 and agamous showed additive phenotypes. Ectopic petals in the third whorl of fr11 ag flowers were serrated, indicating that the FRL1 gene acts in petal and sepal development in an organ-specific manner.

Arabidopsis↗
PubMed2000

Dynamic ultrastructure of mouse pulmonary alveoli revealed by an in vivo cryotechnique in combination with freeze-substitution.

A morphological approach to cell dynamics is usually difficult, since routine preparative techniques for electron microscopy always induce artifacts due to cessation of the blood supply into organs. An in vivo cryotechnique followed by the freeze-substitution method probably reduces such problems. It was applied for examining the pulmonary alveoli of BALB/c mice in vivo. The following ultrastructural features were revealed. (1) A surfactant layer provided a continuous covering to the alveolar epithelium. (2) Pleural epithelial cells, alveolar cells and endothelial cells contained many small vesicles and pits. In the alveolar epithelium, they were often localised near microtubules. (3) Typical lamellar structures in large alveolar epithelial cells were rarely detected. (4) Circulating erythrocytes with various shapes were observed in branching blood capillaries. (5) A close association between erythrocytes and the endothelium was seen at the peripheral alveolar septum. Such ultrastructural arrangements may be appropriate for the physiological functions of the pulmonary alveoli, such as exchanges of gases or materials in vivo.

Animals↗
PubMed2000

A randomised controlled trial of Prostar Plus for haemostasis in patients after coronary angioplasty.

OBJECTIVES: to clarify the efficacy and safety of Prostar Plus, a new percutaneous vascular surgical device (PVS) for vascular haemostasis. DESIGN: prospective randomised controlled trial. METHODS: a consecutive series of 60 patients were randomised to either PVS (n =30) or conventional manual compression ( n =30) following coronary angioplasty or stenting with femoral access using an 8-F sheath. RESULTS: PVS significantly shortened the time to haemostasis (10 s.d. 3 vs. 27 s.d. 9 min, p <0.001), ambulation (2.2 s.d. 0.9 vs. 11.0 s.d. 1.4 h, p <0.001), and discharge (2.2 s.d. 0.4 vs. 3.1 s.d. 0.7 days, p <0.01), compared with the manual compression group with no major complications. PVS also increased patient comfort assessed by using a visual-analogue scale method. Although these clinical benefits reduced the hospital cost ($1301 s. d. 248 vs. 1613 s.d. 460, p <0.05), the cost of the PVS device (approximately $350) cancelled the cost-saving benefit. CONCLUSIONS: this randomised study indicates that Prostar Plus is safe, more effective and comfortable than conventional manual compression.

Angioplasty, Balloon, Coronary↗
PubMed2000

Echocardiographic and pathological evaluation of atherosclerosis in the ascending aorta during coronary artery bypass grafting.

UNLABELLED: We performed intraoperative echocardiography with an epiaortic probe to assess the correlation between echocardiographic appearance and pathological findings of the aorta and to examine the effect of cross-clamping on the aortic wall in 276 patients who underwent coronary artery bypass grafting. The ascending aorta was divided into three segments as follows: lower (L), upper (U), and innominate. The anterior (ant) and posterior (post) intimal thicknesses of each of the three segments were measured. The echogenicity at each of the six locations was examined and was classified as isoechoic or nonisoechoic (hyperechoic, hypoechoic, or mixed type). Tissue punched from the ant L wall of the ascending aorta for vein anastomosis was examined for the presence of atheroma. At the ant L, the prevalence of atheroma was significantly higher in nonisoechoic walls than in isoechoic walls (P = 0.049). We divided patients into two groups according to echogenicity at the U segments. Group A (n = 213) consisted of patients whose echogenicities at both ant U and post U were isoechoic. Group B (n = 63) consisted of patients with nonisoechoic echogenicity at ant U and/or post U. The intimal thicknesses at all six locations in Group B patients were greater than those of Group A (P < 0.01). Deformities at the clamp site after cardiopulmonary bypass were observed significantly more often in Group B than in Group A (P < 0.01). Our data suggest that a nonisoechoic aortic wall indicates more advanced atheroma and a higher risk of deformities at the clamp site. Examination of the echogenicity of the ascending aorta may be one method to reduce perioperative neurological complications. IMPLICATIONS: We performed epiaortic echocardiography during coronary artery bypass grafting and found that the presence of atheroma and deformities at the cross-clamping site were significantly more prevalent in nonisoechoic walls than isoechoic walls.

Aged↗
PubMed2000

Hd1, a major photoperiod sensitivity quantitative trait locus in rice, is closely related to the Arabidopsis flowering time gene CONSTANS.

A major quantitative trait locus (QTL) controlling response to photoperiod, Hd1, was identified by means of a map-based cloning strategy. High-resolution mapping using 1505 segregants enabled us to define a genomic region of approximately 12 kb as a candidate for Hd1. Further analysis revealed that the Hd1 QTL corresponds to a gene that is a homolog of CONSTANS in Arabidopsis. Sequencing analysis revealed a 43-bp deletion in the first exon of the photoperiod sensitivity 1 (se1) mutant HS66 and a 433-bp insertion in the intron in mutant HS110. Se1 is allelic to the Hd1 QTL, as determined by analysis of two se1 mutants, HS66 and HS110. Genetic complementation analysis proved the function of the candidate gene. The amount of Hd1 mRNA was not greatly affected by a change in length of the photoperiod. We suggest that Hd1 functions in the promotion of heading under short-day conditions and in inhibition under long-day conditions.

Amino Acid Sequence↗
PubMed2000

A case of stage-IVb cervical adenocarcinoma successfully treated by combination chemotherapy: case report.

A 54-year-old patient with a Stage IVb adenocarcinoma of the cervix was treated with combination chemotherapy. This regimen consisted of intravenous cisplatin (70 mg/m2) and aclacinomycin A (30 mg/m2) on Day 1, followed by mitomycin C (5 mg/m2) on Day 2 and 3. A pathologically complete response was achieved by this regimen. The patient is well and has been free of symptoms for 66 months.

Adenocarcinoma↗
PubMed2000

Surgical management of genital prolapse: is chain cystourethrography useful for evaluating anatomical corrections and urinary symptoms after surgery?

OBJECTIVE: To evaluate the relationship between chain cystourethrography and surgery for genital prolapse and urinary symptoms. METHODS: A retrospective study of women with genital prolapse was conducted from January 1991 through December 1997. To assess the preoperative and postoperative anatomical situations objectively, chain cystourethrography was performed. RESULTS: Fifty-seven patients underwent surgical repairs for genital prolapse. All of them recovered from the genital prolapse both subjectively and objectively after surgery. Chain cystourethrography is useful for evaluating postoperative anatomical corrections. However, 6 patients (12%) suffered from a recurrent feeling of genital prolapse, and 14 patients (28%) had urinary symptoms postoperatively. CONCLUSIONS: Our treatment showed good anatomical corrections based on chain cystourethrography, and there were no prognostic differences among the surgical procedures. However, anatomical correction does not always mean improvement of urinary symptoms. Further studies are needed to clarify what factors contribute to the prognosis in such cases.

Adult↗
PubMed2000

TT virus infection in patients with fulminant hepatic failure.

OBJECTIVE: A new DNA virus, which has been designated the TT virus, was discovered in 1997. It is not clear whether TT virus is a cause of any of the types of hepatitis. We conducted a case-control study to test the hypothesis that the presence of TT virus is a necessary condition for the development of fulminant hepatic failure in people who have non-A, -B, or -C hepatitis. METHODS: We studied 55 patients with fulminant hepatic failure [28 men, 27 women, mean (+/- SD) age, 47 +/- 15 yr], 32 patients with acute hepatitis (18 men, 14 women, mean age, 38 +/- 15 yr), and 200 healthy subjects (106 men, 94 women, mean age, 42 +/- 14 yr). TT virus DNA was detected in sera by a nested polymerase chain reaction using a primer set for genotype 1. RESULTS: TT virus was more frequently detected in patients with fulminant hepatic failure [in 33 of 55 (60%); 95% confidence interval (CI), 47-73%] than in those with acute hepatitis [in 8 of 32 (25%); 95% CI, 10-40%; p = 0.0016] or in healthy subjects [in 50 of 200 (25%); 95% CI, 19-31%; p < 0.0001]. TT virus was detected at a significantly higher rate in non-A, -B, or -C fulminant hepatic failure [in 18 of 22 (82%); 95% CI, 66-98%] than in fulminant hepatic failure of A, B, or C type [45%, 28-62%, 15/33; p = 0.007] or in non-A, -B, or -C acute hepatitis [24%, 3-44%, 4/17; p = 0.0003]. The logistic regression analysis selected TT virus (p = 0.0009), age (p = 0.0116), and etiology (p = 0.0309) as independent variables associated with fulminant hepatic failure (coefficient of determination, 0.2335). CONCLUSIONS: TT virus comparatively plays a role in the pathogenesis of non-A, -B, or -C fulminant hepatic failure.

Acute Disease↗
PubMed2000

Dynamic contrast-enhanced MR imaging of uterine cervical cancer: pharmacokinetic analysis with histopathologic correlation and its importance in predicting the outcome of radiation therapy.

PURPOSE: To investigate the histopathologic bases of different enhancement patterns on dynamic contrast material-enhanced magnetic resonance (MR) images of cervical cancer and to assess their importance in predicting the outcome of patients after radiation therapy. MATERIALS AND METHODS: Dynamic enhanced MR imaging and pharmacokinetic analyses were performed in 26 patients with cervical cancer who subsequently underwent hysterectomy and in 36 patients with cervical cancer who received radiation therapy. Histopathologic findings and clinical outcomes were correlated with results of dynamic MR imaging and pharmacokinetic analysis. RESULTS: On dynamic MR images of the surgical patients, areas with intense homogeneous enhancement showed increased permeability (k = 27.4 x 10(-3)) compared with areas with poor enhancement (k = 19.0 x 10(-3)). Well-enhanced areas were predominantly composed of cancer cell fascicles, whereas poorly enhanced areas were composed of fibrous tissue with scattered cancer cells. Radiation therapy was more effective in tumors with higher tissue permeability (k = 31.3 x 10(-3)) on dynamic MR images than in those with lower tissue permeability (k = 18.3 x 10(-3)). CONCLUSION: Areas of increased contrast enhancement are mainly composed of abundant cancer cell fascicles, whereas poorly perfused areas are composed of fibrous tissue with scattered cancer cells. Radiation therapy is more effective in well-enhanced tumors, resulting in improved local control.

Adenocarcinoma↗
PubMed2000

Topographical difference of cytoskeletal organization in smooth muscle cells of rat duodenum revealed by quick-freezing and deep-etching method.

The sarcolemmal domain of rat duodenal smooth muscle cells includes caveolae and associated cytoskeletal or filamentous elements. We have used the quick-freezing, deep-etching method to examine the three dimensional relationships between these components. Replica membranes for separated strips of rat duodenal muscle layers were routinely prepared after extraction soluble proteins from cytoplasm and extracellular matrix. As results, 1) cytoskeletal elements in smooth muscle cells consisted mainly of striated thin filaments; 2) thin filaments were connected with some plasma membranes through filaments associated with the sarcolemma, which formed fine network structures beneath the sarcolemma; 3) many bridging structures between the filaments associated with the sarcolemma and the extracellular matrix were frequently detected in the plasma membrane; and 4) compact filaments associated with the sarcolemma almost disappeared near the caveolae, and only thin filaments were anchored to their neck parts. The special arrangement of the cytoskeletal components, which is probably necessary for the intestinal motility, characterizes the topographical difference of the smooth muscle sarcolemma.

Animals↗