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T Takagi

Publications and source records attributed to T Takagi.

At least 37 records · Page 2Linked to original sources

Effect of Garcinia cambogia extract on serum leptin and insulin in mice.

In this study we examined the effects of 3.3% Garcinia cambogia extract on 10% sucrose loading in mice for 4 weeks. Treatment was found to have no effect on body weight, fat pad weight or serum glucose level. On the other hand, serum total cholesterol, triglycerides, NEFA were observed. Levels of serum insulin and leptin, as well as the leptin/WAT ratio, were lower in the treated mice than in the control. These findings suggested that G. cambogia extract efficiently improved glucose metabolism and displayed leptin-like activity.

Animals↗

Clinical significance of nm23-H1 proteins expressed on cell surface in non-Hodgkin's lymphoma.

The nm23 gene was isolated as a metastasis suppressor gene that exhibits low expression in high-level metastatic cancer cells. Its gene is related to the prognosis of acute myelogenous leukemia (AML) and non-Hodgkin's lymphoma (NHL). In this study, we examined the expression of nm23-H1 protein on the lymphoma cell surface of NHL. In 28 of 108 cases (25.9%), we observed > or = 20% of cell surface nm23-H1 protein expression and expression was especially high in peripheral T cell lymphomas and extranodal NK/T cell lymphomas. We also observed a significant correlation between serum nm23-H1 level and cell surface nm23-H1 expression levels. In patients with high levels of cell surface nm23-H1 expression, overall and progression-free survival rates were significantly lower than those in patients with low surface nm23-H1 expression levels. When surface nm23-H1 and serum nm23-H1 were combined, patients with high levels of both exhibited a poorer prognosis than patients with a high level of one or the other. These results indicate that in addition to serum nm23-H1, cell surface nm23-H1 may be used as a prognostic factor in planning a treatment strategy. The nm23-H1 protein appears to be intimately related to biological aggressiveness of lymphoma and, therefore, might be a molecular target of NHL treatment.

Adult↗

Coronary flow velocity analysis during short term follow up after coronary reperfusion: use of transthoracic Doppler echocardiography to predict regional wall motion recovery in patients with acute myocardial infarction.

BACKGROUND: A recent study using a Doppler guide wire showed that coronary flow velocity measurements immediately after coronary reperfusion were useful in predicting recovery of regional left ventricular function. The value of coronary flow velocity analyses during follow up after reperfusion has not been established in the clinical setting. OBJECTIVE: To evaluate coronary flow velocity measurements in predicting recovery of regional left ventricular function during short term follow up after acute anterior myocardial infarction, using transthoracic Doppler echocardiography (TTDE). METHODS: 30 consecutive patients with anterior acute myocardial infarction were studied. They all underwent successful coronary angioplasty for lesions in the left anterior descending coronary artery (LAD). Using TTDE, coronary flow velocity in the LAD was recorded on days 1 and 3, and at one and two weeks after reperfusion. Regional wall motion was analysed by the wall motion score index (WMSI), calculated as an average of segmental scores in the LAD territory before reperfusion and one month after the infarction. RESULTS: Deceleration time of diastolic flow velocity (DDT) in patients with viable myocardium (WMSI in LAD territory at one month, < 2.0) was significantly longer after recanalisation than in patients without viable myocardium (WMSI in LAD territory at one month, > 2.0): 657 (226) v 271 (117) ms on day 1, p < 0.001; 732 (219) v 373 (217) ms on day 3, p < 0.01; and 903 (107) v 577 (300) ms at one week, p < 0.01. However, the difference at two weeks (991 (75) v 795 (281) ms) was not significant. For the prediction of viable myocardium, DDT > 600 ms had a sensitivity of 78% and a specificity of 92% on day 1, and a sensitivity of 78% and a specificity of 84% on day 3. At one and two weeks, DDT > 600 ms was sensitive (100% and 100%, respectively) but less specific (46% and 26%, respectively) for predicting viable myocardium. CONCLUSIONS: Non-invasive assessment of coronary flow velocity using TTDE within three days of successful coronary angioplasty in patients with anterior acute myocardial infarction is useful in predicting recovery of regional left ventricular function.

Blood Flow Velocity↗

DIGIT: a novel gene finding program by combining gene-finders.

We have developed a general purpose algorithm which finds genes by combining plural existing gene-finders. The algorithm has been implemented into a novel gene-finder named DIGIT. An outline of the algorithm is as follows. First, existing gene-finders are applied to an uncharacterized genomic sequence (input sequence). Next, DIGIT produces all possible exons from the results of gene-finders, and assigns them their exon types, reading frames and exon scores. Finally, DIGIT searches a set of exons whose additive score is maximized under their reading frame constraints. Bayesian procedure and a hidden Markov model are used to infer exon scores and search the exon set, respectively. We have designed DIGIT so as to combine the results of FGENESH, GENSCAN and HMMgene, and have assessed its prediction accuracy by using recently compiled benchmark data sets. For all data sets, DIGIT successfully discarded many false-positive exons predicted by individual gene-finders and yielded remarkable improvements in sensitivity and specificity at the gene level compared with the best gene level accuracies achieved by any single gene-finder.

Algorithms↗

Regeneration of hypogastric nerve using a polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge proved electrophysiologically in a canine model.

The hypogastric nerve (HGN) is a sympathetic nerve in the peritoneal cavity and controls urinary and seminal functions. In this study, the regeneration of HGN was determined by using a new type of an artificial nerve conduit, polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge in two dogs. A PGA-collagen nerve conduit (diameter=2 mm) was interposed in a 10 mm gap of the right HGN. The regeneration of the HGN was evaluated electrophysiologically 8 months after the operation. The intraluminal pressure of spermatic duct and the bladder neck were elevated 80 mmHg and 25 mmHg respectively by the stimulation across the regenerated HGN. The prostate contraction was also elicited. The responses diminished after the excision of the regenerated portion of HGN. These results proved the regeneration of HGN and this nerve conduit will be great help for patients who suffer from urinary and seminal disturbances.

Animals↗

Differential gene expression profiles of gastric cancer cells established from primary tumour and malignant ascites.

Advanced gastric cancer is often accompanied by metastasis to the peritoneum, resulting in a high mortality rate. Mechanisms involved in gastric cancer metastasis have not been fully clarified because metastasis involves multiple steps and requires a combination of altered expressions of many different genes. Thus, independent analysis of any single gene would be insufficient to understand all of the aspects of gastric cancer peritoneal dissemination. In this study, we performed a global analysis of the differential gene expression of a gastric cancer cell line established from a primary main tumour (SNU-1) and of other cell lines established from the metastasis to the peritoneal cavity (SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB). The application of a high-density cDNA microarray method made it possible to analyse the expression of approximately 21 168 genes. Our examinations of SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB showed that 24 genes were up-regulated and 17 genes down-regulated besides expression sequence tags. The analysis revealed the following altered expression such as: (a) up-regulation of CD44 (cell adhesion), keratins 7, 8, and 14 (epitherial marker), aldehyde dehydrogenase (drug metabolism), CD9 and IP3 receptor type3 (signal transduction); (b) down-regulation of IL2 receptor gamma, IL4-Stat (immune response), p27 (cell cycle) and integrin beta4 (adhesion) in gastric cancer cells from malignant ascites. We then analysed eight gastric cancer cell lines with Northern blot and observed preferential up-regulation and down-regulation of these selected genes in cells prone to peritoneal dissemination. Reverse transcriptase-polymerase chain reaction confirmed that several genes selected by DNA microarray were also overexpressed in clinical samples of malignant ascites. It is therefore considered that these genes may be related to the peritoneal dissemination of gastric cancers. The results of this global gene expression analysis of gastric cancer cells with peritoneal dissemination, promise to provide a new insight into the study of human gastric cancer peritoneal dissemination.

Animals↗

Quantitative analysis of NF-kappaB-expression in cartilage and synovium of rat knee induced by intra-articular injection of synthetic lipid A.

OBJECTIVE: NF-kappaB expression in cartilage and synovium of rat knee after intra-articular injection of lipid A was investigated. METHODS: Inflammation was evaluated in histological sections stained with hematoxylin and eosin, toluidine blue and immunostained with monoclonal anti-NF-kappaB antibody or monoclonal anti-TNF-alpha antibody. RESULTS: Inflammatory cell infiltration into the synovium, hyperplasia of synovial lining layers, loss of metachromasia of cartilage, TNF-alpha-positive cells and NF-kappaB-positive cells in the synovium and cartilage were observed in all 26 rat knees intra-articularly injected with lipid A. The numbers of TNF-alpha-positive and NF-kappaB-positive synovial cells and chondrocytes after the injection were significantly greater than those in knees injected with triethylamine (p < 0.05). The amount of inflammatory cell infiltration into the synovium, synovial lining layers, TNF-alpha-positive synovial cells and NF-kappaB-positive synovial cells 12 h after the injection was significantly smaller than those after 1 day (p < 0.05). CONCLUSION: Intra-articular injection of lipid A induced NF-kappaB expression in cartilage and synovium. Cartilage degeneration started earlier than synovitis in this model. Quantitative analysis of NF-kappaB in cartilage might be useful to evaluate the extreme acute phase of cartilage degeneration.

Animals↗

Intravenous sedation and general anesthesia for a patient with Gilles de la Tourette's syndrome undergoing dental treatment.

Patients with Gilles de la Tourette's syndrome develop symptoms during childhood. Repetitive various motor tics or speech tics that are spontaneous, aimless, and involuntary are characteristic of the syndrome (1). Patients with the syndrome have been considered to have an aggressive, impulsive, and obsessive character (2). (3). Suicide is one of the mental symptoms of the syndrome. Routine dental treatment with this syndrome can be difficult.

Adolescent↗

Ubiquitin-proteasome inhibitor enhances tumour necrosis factor-alpha-induced apoptosis in rat gastric epithelial cells.

BACKGROUND: Tumour necrosis factor (TNF-alpha) is a candidate factor for involvement in inflammation-mediated gastric mucosal injury. However, the effect of this cytokine on gastric epithelial cells has been poorly investigated. In the present study, we examined whether gastric epithelial cells are resistant to TNF-alpha-induced apoptosis, and whether this resistance is related to ubiquitin-proteasome-associated nuclear factor-kappaB (NF-kappaB) activation. METHODS: The rat gastric mucosal cell line RGM-1 was grown in DMEM/F12 medium supplemented with 10% FCS. Confluent monolayers of cells were pretreated or not for 60 min with PSI, a peptide aldehyde known to specifically inhibit the chymotrypsin-like activity of 26S proteasome. Cells were subsequently stimulated with recombinant rat TNF-alpha and their viability was determined by WST-1 assay. Apoptosis was confirmed by fluorescence microscopy after staining with Hoechst 33342 and propidium iodide, and DNA fragmentation was determined by flow cytometry using an APO-BRDU kit. IkappaB-alpha and the p65 binding subunit of NF-kappaB were detected by Western blots. RESULTS: Twenty-four-hour incubation with TNF-alpha alone or PSI alone did not affect the cell viability of RGM-1 cells. Pretreatment with PSI significantly enhanced the level of apoptosis induced by TNF-alpha. In RGM-1 cells treated with TNF-alpha, cytoplasmic IkappaB-alpha decreased and p65 in nuclear extracts increased markedly 30 min after cytokine stimulation. Pretreatment with PSI at 12.5 micromol/L blocked these TNF-alpha-induced changes. CONCLUSION: PSI enhances TNF-alpha-induced apoptosis through inhibition of NF-kappaB activation in RGM-1 cells.

Animals↗

Substitution of Dmo1 with normal alleles results in decreased manifestation of diabetes in OLETF rats.

AIM: Dmo1 (Diabetes Mellitus OLETF type I) is a major quantitative trait locus for dyslipidaemia, obesity and diabetes phenotypes in the Otsuka Long Evans Tokushima Fatty (OLETF) rat strain. To evaluate possible metabolic and pathological improvements generated by correction of the Dmo1 genetic pathway, we produced congenic lines, in which both OLETF Dmo1 alleles are replaced by the F344-derived genome. METHODS: Congenic animals were produced by introgressing F344-derived Dmo1 alleles into the OLETF rat. Congenic animals of the fourth generation (BC4) were intercrossed to obtain F1 animals (BC4:F1). Animals of the next generation, BC4:F2, were used for this study. We used 23 BC4:F2 males harbouring homozygous replacement of the OLETF Dmo1 region with the F344-derived genome. Seven animals with OLETF-derived Dmo1 alleles were used as controls. RESULTS: Dmo1-F344/F344 congenic rats showed significant decreases in body weight, abdominal fat weight, serum triacylglycerols, total cholesterol, food consumption and blood glucose after glucose loading (13%, 39%, 45%, 27%, 18% and 27% respectively; p < 0.05) compared with Dmo1-OLETF/OLETF animals. Furthermore, histopathological analysis of the kidney showed that mesangial sclerosis, hyalin deposits and deposition of PAS-positive substance were significantly lower in Dmo1-F344/F344 animals (p < 0.05). CONCLUSION: Improvements in metabolic parameters and histopathological scores show that correction of the Dmo1 genetic pathway in the diabetic and mildly obese OLETF rat strain produces wide-ranging therapeutic effects. Thus, this pathway might represent a new drug target also applicable to humans.

Animals↗

Non-invasive automated assessment of the ratio of pulmonary to systemic flow in patients with atrial septal defects by the colour Doppler velocity profile integration method.

BACKGROUND: The recent introduction of the automated cardiac flow measurement (ACM) method, using spatiotemporal integration of the Doppler velocity profile, provides a quick and accurate automated calculation of cardiac output. OBJECTIVE: To evaluate the ACM method against oximetry during cardiac catheterisation for estimating the Qp/Qs (pulmonary to systemic flow) ratio in patients with an atrial septal defect. METHODS: Left and right ventricular stroke volume (LVSV, RVSV) were calculated by ACM in 22 patients with an atrial septal defect who underwent cardiac catheterisation and in 11 patients without heart disease (control group). With ACM, the Qp/Qs ratio was estimated from RVSV divided by LVSV. In the patients with an atrial septal defect, the Qp/Qs ratio was assessed by oximetry at the time of cardiac catheterisation. RESULTS: There was a good correlation between LVSV and RVSV obtained by ACM in the control group (r = 0.98, y = 0.97x + 0.25, SEE = 2.9 ml). The mean difference between LVSV and RVSV by ACM was -1.25 (2.76) ml. The Qp/Qs ratio obtained by ACM in the control group was 0.98 (0.06). The Qp/Qs ratio in patients with an atrial septal defect was significantly higher than in the control group (3.11 (1.20), p < 0.001). ACM determination of the Qp/Qs ratio correlated well with oximetry determination (r = 0.86, y = 0.75x + 0.55, SEE = 0.64). The mean difference between ACM and oximetry for the measurement of the Qp/Qs ratio was -0.28 (0.69). CONCLUSIONS: The newly developed ACM method is clinically useful for non-invasive automated estimations of the Qp/Qs ratio in patients with an atrial septal defect.

Adult↗

Development of Dunn osteosarcoma inoculated into subcutaneous air pouch in mice.

Dunn osteosarcoma cell growth was observed in C3H/Hej mouse subcutaneous air pouch. Inoculation with Dunn osteosarcoma cell suspension was performed by injection into air pouches of 70 mice on Day 7 after the initial injection of air. The developmental pattern of the tumor cell colonies was classified histologically into five stages. In Stage 0 (stage of no tumor cells), there were no tumor cells. In Stage 1 (focal stage), the colonies were limited to the lining-cell layers. In Stage 2, (segmental stage) the colonies protruded into the cavity of the pouch. In Stage 3 (annular stage), the total surface of the inner wall of the pouch was occupied by tumor cells. In Stage 4 (occlusive stage), the cavity of the pouch was fully occupied by tumor cells. The tumor was observed to develop to stage 1 in all mice 7 days after inoculation. The colonies were all found to be settled initially in the deeper layer of lining cells. Thus, the mouse air-pouch model is useful for direct observation of osteosarcoma cell growth.

Animals↗

Quantitative assessment of harmonic power Doppler myocardial perfusion imaging with intravenous Levovist in patients with myocardial infarction: comparison with myocardial viability evaluated by thallium-201 single-photon emission computed tomography and coronary flow reserve.

BACKGROUND: Intravenous myocardial contrast echocardiography with harmonic power Doppler imaging is a novel technique for assessing myocardial perfusion. AIMS: The aim of this study was to quantitatively assess myocardial perfusion by harmonic power Doppler imaging in patients with a previous myocardial infarction and compare myocardial contrast echocardiography results with myocardial viability evaluated by thallium-201 single-photon emission computed tomography ((201)Tl-SPECT) and the results of Doppler flow measurement of coronary flow velocity reserve. METHODS: Twenty-three patients with anterior myocardial infarction who were scheduled for adenosine stress (201)Tl-SPECT underwent myocardial contrast echocardiography with harmonic power Doppler imaging. Harmonic power Doppler imaging was performed at rest and during adenosine infusion (0.15 mg/kg/min) using an intravenous infusion of Levovist. The peak colour pixel intensity ratios of the risk area to the control area were used for quantitative analysis of myocardial perfusion by harmonic power Doppler imaging. Coronary blood flow velocity was measured using Doppler-tipped guidewire in the distal portion of left anterior descending artery and coronary flow velocity reserve was calculated. RESULTS: In patients with myocardial viability assessed by (201)Tl-SPECT, pixel intensity ratios both at rest and during hyperaemia were significantly higher compared with those in patients without myocardial viability (at rest: 0.62 +/- 0.28 vs 0.37 +/- 0.17, P=0.038, during hyperaemia 0.72 +/- 0.19 vs 0.40 +/- 0.18, P=0.003). Coronary flow velocity reserve was significantly different between two groups (2.35 +/- 0.43 vs 1.49 +/- 0.53, P <0.01). CONCLUSIONS: Quantitative assessment of microvascular integrity by harmonic power Doppler imaging corresponds to the evaluation of the microcirculation by coronary flow velocity reserve.

Adenosine↗

Menstrual and reproductive factors for subarachnoid hemorrhage risk in women: a case-control study in nagoya, Japan.

BACKGROUND AND PURPOSE: We sought to examine the relationship between menstrual and reproductive factors and the risk of subarachnoid hemorrhage (SAH), using a case-control study. METHODS: Cases consisted of a consecutive series of 124 women patients with first spontaneous SAH aged 30 to 79 years and confirmed aneurysm(s) by angiography and/or CT scan. Hospital and community controls subjects were identified, matched to each case by age (+/-2 years). RESULTS: Increased SAH risk was associated with (1) earlier age at menarche (adjusted odds ratio [OR]=3.24 for age <13 years compared with age >/=13 years; 95% CI, 1.25 to 4.03) and (2) nulligravidity (adjusted OR=4.23; 95% CI, 1.05 to 7.56). No significant association of SAH risk was found with regularity of menstrual cycle, age at pregnancy, age at first birth, and number of births. The greatest risk was for the combined effect of nulligravidity and earlier menarche (<13 years) (adjusted OR=6.37; 95% CI, 1.12 to 36.2). CONCLUSIONS: The combined effect of several variables related to menstrual and reproductive history may exert a greater influence on risk of SAH compared with a single menstrual or reproductive variable.

Adult↗

Prediction of co-regulated genes in Bacillus subtilis on the basis of upstream elements conserved across three closely related species.

BACKGROUND: Identification of co-regulated genes is essential for elucidating transcriptional regulatory networks and the function of uncharacterized genes. Although co-regulated genes should have at least one common sequence element, it is generally difficult to identify these genes from the presence of this element because it is very easily obscured by noise. To overcome this problem, we used conserved information from three closely related species: Bacillus subtilis, B. halodurans and B. stearothermophilus. RESULTS: Even though such species have a limited number of clearly orthologous genes, we obtained 1,884 phylogenetically conserved elements from the upstream intergenic regions of 1,568 B. subtilis genes. Similarity between these elements was used to cluster these genes. No other a priori knowledge on genes and elements was used. We could identify some genes known or suggested to be regulated by a common transcription factor as well as genes regulated by a common attenuation effector. CONCLUSIONS: We confirmed that our method generates relatively few false positives in clusters with higher scores and that general elements such as -35/-10 boxes and Shine-Dalgarno sequence are not major obstacles. Moreover, we identified some plausible additional members of groups of known co-regulated genes. Thus, our approach is promising for exploring potentially co-regulated genes.

Bacillus subtilis↗

Intracerebroventricular injection of pipecolic acid inhibits food intake and induces sleeping-like behaviors in the neonatal chick.

It has been demonstrated that L-pipecolic acid (L-PA), a major metabolic intermediate of L-Lysine (L-Lys) in the brain, is involved in the functioning of Gamma-aminobutyric acid. In the present work the effect of intracerebroventricular (i.c.v.) administration of L-PA, and its relatives, on food intake and behavior in neonatal chicks was investigated. The i.c.v. injection of 1 mg of L-PA and D-PA significantly inhibited food intake during the 2 h following injection, whereas greater than 2 mg of L-Lys was required to inhibit food intake. In behavioral tests, the i.c.v. injection of L-PA reduced active wakefulness and feeding behavior while inducing sleeping-like behavior in chicks. These results suggest that L-PA has an important role for the regulation of behaviors in the neonatal chick after conversion from L-Lys in the brain.

Age Factors↗

Feeding responses to several neuropeptide Y receptor agonists in the neonatal chick.

Neuropeptide Y is one of the most potent neuropeptides known to induce feeding in animals, and has been suggested to be a physiological signal for food intake. It has been also reported that intracerebroventricular injection of neuropeptide Y stimulates feeding behavior of the neonatal chick. There are many neuropeptide Y receptor agonists that have not been investigated in feeding response of the neonatal chick. The aim of this study is to elucidate whether central injection of several neuropeptide Y receptor agonists stimulates feeding of the neonatal chick over 2 h. We found that central injections of [Leu(31), Pro(34)]neuropeptide Y, peptide YY, human pancreatic polypeptide and rat pancreatic polypeptide significantly stimulated food intake of neonatal chicks throughout the 2-h post-injection period. Neuropeptide Y-(13-36) significantly stimulated feeding at 30 min, but not thereafter. [D-Trp(32)]neuropeptide Y stimulated feeding at 60 and 120 min, but not 30 min, post-injection. Central administration of rat pancreatic polypeptide, which does not increase food intake in rats, stimulated feeding in chicks. This result reflects structural differences of the neuropeptide Y receptor subtypes and/or differences in mechanisms stimulating feeding behavior between mammals and chickens. In conclusion, neuropeptide Y receptor agonists, except for neuropeptide Y-(13-36), are potent stimulators of food intake in the neonatal chick.

Animals↗

Prediction of sensitivity of esophageal tumors to adjuvant chemotherapy by cDNA microarray analysis of gene-expression profiles.

We applied cDNA microarray analyses of 9216 genes to establish a genetic method for predicting the outcome of adjuvant chemotherapy to esophageal cancers. We analyzed expression profiles of 20 esophageal cancer tissues from patients who were treated with the same adjuvant chemotherapy after removal of tumor by operation, and we attempted to find genes associated with the duration of survival after surgery. By comparing expression profiles of those cancer tissues, we identified by statistical analysis 52 genes that were likely to be correlated with prognosis and possibly with sensitivity/resistance to the anticancer drugs. We also developed a drug response score based on the differential expression of these genes, and we found a significant correlation between the drug response score and individual patients' prognoses. Our results indicated that this scoring system, based on microarray analysis of selected genes, is likely to have great potential for predicting the prognosis of individual cancer patients with the adjuvant chemotherapy.

Aged↗