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T Aoki

Publications and source records attributed to T Aoki.

At least 37 records · Page 2Linked to original sources
PubMed2004

Chiari malformation type I associated with familial spastic paraplegia: report of a surgically treated case.

CASE REPORT: We describe the case of a 7-year-old girl with Chiari malformation type I (CMI) and concomitant familial spastic paraplegia (FSP), who exhibited spastic gait disturbance. She also showed poor results on the standing tolerance test using thermography, which evaluates autonomic nerve function. The patient was subjected to posterior fossa decompression and cervical 1 (C1) laminectomy for CMI based on the result of the standing tolerance test. After the operation her gait disturbance and autonomic nerve dysfunction improved. DISCUSSION: Although no cases of CMI and concomitant FSP have been reported, due to the fact that autonomic nerve dysfunction is one of CMI symptoms but never FSP, the diagnosis of autonomic nerve dysfunction of CMI using the standing tolerance test played an important role in selecting the surgical procedure for this case.

Arnold-Chiari Malformation↗
PubMed2004

Isolation of an active element from a high-copy-number family of retrotransposons in the sweetpotato genome.

A large number of plant retrotransposons have been characterized, but only three families ( Tnt1, Tto1 and Tos17) have been demonstrated to be transpositionally competent. We have used a novel approach to identify an active member of the Ty1- copia retrotransposon family with estimated 400 copies in the sweetpotato genome. Ty1- copia reverse transcriptase (RTase) sequences from the sweetpotato genome were analyzed, and a group of retrotransposon copies that probably arose by recent transposition events was identified and analyzed further. Transcripts containing long terminal repeats (LTRs) of this group were amplified from callus cDNA by the 3'RACE technique. Patterns of sequence-specific amplification polymorphism (S-SAP) of the LTR sequences in genomic DNA were compared between a normal plant and callus lines derived from it. In this way, a callus-specific S-SAP product was identified, which apparently resulted from the insertion of the retrotransposon detected by 3'RACE during cell culture. We conclude that our approach provides an effective way to identify active elements among the members of high-copy-number retrotransposon families.

Base Sequence↗
PubMed2004

Crossover trial for lipid abnormality in postmenopausal breast cancer patients during selective estrogen receptor modulators (SERMs) administrations.

The objective of this study was to evaluate the different profiles of serum lipids resulting from the administration of selective estrogen receptor modulators (SERMs). Postmenopausal primary breast cancer patients (n = 197) with node-negative, hormone receptor-positive who were treated at our department or in other related medical institutions from April 1997 through March 2001 were given adjuvant therapy. The adjuvant therapy included 1 year's administration of tamoxifen (TAM) 20 mg or toremifene (TOR) 40 mg. The profiles of serum lipids such as total cholesterol (TC), high-density lipoprotein cholesterol (HDL) and triglyceride (TG) were observed. After 1 year administration TC had significantly decreased (p < 0.001) both in the TAM group and the TOR group, but no significant difference was found between these groups (p = 0.249). HDL had significantly decreased in the TAM group (p < 0.001), while it had significantly increased in the TOR group (p < 0.001), and a significant difference was found between the groups (p < 0.001). TG had significantly increased in the TAM group (p < 0.001) but significantly decreased in the TOR group (p < 0.001). The medication was switched in those who still had abnormal lipid metabolism and given to them for another year. After 1 year from the crossover TC and HDL had increased to the levels of before administration (p < 0.001) and TG had decreased in those (n = 57) whose medication was switched from TAM to TOR. While TC had decreased and TG had increased in those (n = 23) whose medication was switched from TOR to TAM (p < 0.001). The above findings have suggested that TOR provides better profiles of lipid metabolism than TAM.

Administration, Oral↗
PubMed2004

Clustering of C-type lectin natural killer receptor-like loci in the bony fish Oreochromis niloticus.

The genome of the cichlid (teleost) fish Oreochromis niloticus contains a set of genes which encode group V C-type lectin proteins homologous to the mammalian NKG2/CD94 family of natural killer (NK) cell receptors. To determine the genomic organization of these killer cell-like receptor (KLR) genes, an O. niloticus BAC library was screened with a cDNA probe derived previously from an expressed sequence tag of the related cichlid species Paralabidochromis chilotes. Four distinct KLR-bearing BAC clones were analysed, three of which could be assembled into a contig. One of the clones was sequenced in its entirety, whereas the others were partially sequenced to identify the KLR loci borne by them. Altogether, 28 distinct KLR loci were identified, of which at least 26 occupy a single chromosomal region, the KLR complex. One half of the loci appear to be occupied by pseudogenes. Compared to the human NK cell receptor complex, the Oreochromis KLR complex is more compact and, apart from transposons, appears to contain only KLR loci. The gene density of the complex is one KLR locus per 18 kb of sequence. All the KLR loci constituting the complex are derived from a single most recent common ancestor, which is estimated to have existed 7.7 million years ago. The 180 kb of the determined sequence is a mosaic of blocks of similar segments reflecting a complex history of duplications, deletions and rearrangements. The transposons found in the sequenced part belong to the TC1, Xena, CR1 and TX1 families.

Amino Acid Sequence↗
PubMed2004

Fusarium incarnatum isolated from black tiger shrimp, Penaeus monodon Fabricius, with black gill disease cultured in Vietnam.

Fusarium incarnatum was isolated from gill lesions of cultured black tiger shrimp, Penaeus monodon, in every crop during 2000-2002 in Nghe An province, Vietnam. Infected shrimps showed typical signs of black gill disease and mortalities about a month prior to harvest. Detailed morphological examinations, as well as molecular phylogenic analyses based on partial nucleotide sequences of ribosomal DNA, were made on the isolates. An artificial infection of kuruma prawn, Penaeus japonicus, using two selected isolates was also conducted and their pathogenicity determined.

Animals↗
PubMed2004

Mechanical properties of cast Ti-6Al-4V-XCu alloys.

The mechanical properties of Ti-6Al-4V-XCu (1, 4 and 10 wt% Cu) alloys were examined. The castings for each alloy were made in a centrifugal titanium casting machine. Two shapes of specimens were used: a dumbbell (20 mm gauge length x 2.8 mm diameter) for mechanical property studies, and a flat slab (2 mm x 10 mm x 10 mm) for metallography, microhardness determination and X-ray diffractometry. Tensile strength, yield strength, modulus of elasticity, elongation and microhardness were evaluated. After tensile testing, the fracture surfaces were observed using scanning electron microscopy. The tensile strengths of the quaternary alloys decreased from 1016 MPa for the 1% Cu alloy to 387 MPa for the 10% Cu alloy. Elongation decreased with an increase in the copper content. The 1% Cu alloy exhibited elongation similar to Ti-6Al-4V without copper (3.0%). The results also indicated that the copper additions increased the bulk hardness of the quaternary alloy. In particular, the 10% Cu alloy had the highest hardness and underwent the most brittle fracture. The mechanical properties of cast Ti-6Al-4V alloy with 1 and 4% Cu were well within the values for existing dental casting non-precious alloys.

Alloys↗
PubMed2004

Development of less invasive surgical procedures for thoracic esophageal cancer.

In order to minimize the invasiveness of the operative procedure for thoracic esophageal cancer, several procedures have been introduced since January 1997. They included: (i) perioperative use of steroids; (ii) muscle-sparing thoracotomy without costectomy; (iii) preparation of the gastric tube with preservation of sufficient blood supply; (iv) reconstruction of the alimentary tract via posterior-mediastinal route; and (v) formation of anastomosis between the remaining esophagus and the gastric tube at a location between the gastroepiploic arteries of the gastric greater curvature. Twenty-one patients who did not receive preoperative chemoradiotherapy underwent the newly developed procedure, and were compared with those receiving the original procedure. Hospital mortality was zero, and postoperative systemic inflammatory response syndrome was suppressed. The mean postoperative hospital stay was 21.5 days, and the actuarial 3-year survival rate was 76.2%. From the comparison with those receiving the original procedure, it can be concluded that the newly developed procedures were effective in minimizing surgical invasiveness and were sufficiently curative in terms of cancer treatment.

Anastomosis, Surgical↗
PubMed2004

[Intentional limited resection for small adenocarcinoma with ground-glass opacity component more than 50% on computed tomography].

Fifty-eight patients who had small lung tumors 2 cm or less with ground-glass opacity (GGO) component more than 50% on high resolution computed tomography (HRCT) underwent intentional limited resection. After bronchioloalveolar carcinoma without both active fibroblastic proliferation and invasive sign to the stroma was confirmed, limited resection was completed in 50 patients. In 8 patients, procedure was converted lobectomy because of microscopic invasive sign in 4, active fibroblastic proliferation in 2, and other reasons in 2. Unexpected invasive sign was found by detailed post-operative examination in 2 cases. Five-year survival rate was 98% with a mean follow-up period of 48.8 months. A limitation of intra-operative diagnosis was revealed and the accuracy of diagnosis should be improved by not only intra-operative pathological diagnosis but also HRCT images.

Adenocarcinoma↗
PubMed2003

Polarimetry of short-pulse gamma rays produced through inverse Compton scattering of circularly polarized laser beams.

We have developed a polarimetry of ultrashort pulse gamma rays based on the fact that gamma rays penetrating in the forward direction through a magnetized iron carry information on the helicity of the original gamma rays. Polarized, short-pulse gamma rays of (1.1+/-0.2)x10(6)/bunch with a time duration of 31 ps and a maximum energy of 55.9 MeV were produced via Compton scattering of a circularly polarized laser beam of 532 nm off an electron beam of 1.28 GeV. The first demonstration of asymmetry measurements of short-pulse gamma rays was conducted using longitudinally magnetized iron of 15 cm length. It is found that the gamma-ray intensity is in good agreement with the simulated value of 1.0x10(6). Varying the degree of laser polarization, the asymmetry for 100% laser polarization was derived to be (1.29+/-0.12)%, which is also consistent with the expected value of 1.3%.

Journal Article↗
PubMed2003

Genetic diversity and molecular markers of the tropical abalone (Haliotis asinina) in Thailand.

Genetic diversity of abalone in Thailand, Haliotis asinina, H. ovina, and H. varia, was analyzed by polymerase chain reaction (PCR) of 18S and 16S rDNAs, with randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP). Species-specific RAPD markers were found in each abalone species. Restriction analysis of 18S (nuclear) ribosomal DNA with Alu I, Taq I, and Hae III and 16S (mitochondrial) rDNA with Bam HI, Eco RI, Hae III, and Alu I gave 12 and 13 digestion patterns, respectively. A total of 49 composite haplotypes were found. A dendogram obtained by the unweighted pair-group method with arithmetic mean, constructed from divergence between pairs of composite haplotypes, revealed reproductively isolated gene pools of these abalone and indicated that H. asinina and H. ovina are genetically closer than H. varia. When H. varia was discovered owing to small sample sizes, geographic heterogeneity analysis and FST estimate indicated clear genetic differentiation between H. ovina originating from the Andaman Sea (west) and the Gulf of Thailand (east, P<0.0001), whereas partial differentiation was observed between the Philippines and the remaining H. asinina samples (P<0.0021). The amplified 16S rDNAs of individuals representing composite haplotypes found in this study were cloned and sequenced. A neighbor-joining tree constructed from sequence divergence of 16S rDNA accurately allocated those sequences according to species origins of abalone. Species-specific PCR based on 16S rDNA polymorphism was successfully developed in H. asinina and H. varia but not in H. ovina.

Animals↗
PubMed2003

Wear resistance of experimental Ti-Cu alloys.

After using cast titanium prostheses in clinical dental practice, severe wear of titanium teeth has been observed. This in vitro study evaluated the wear behavior of teeth made with several cast titanium alloys containing copper (CP Ti+3.0 wt% Cu; CP Ti+5.0 wt% Cu; Ti-6Al-4V +1.0 wt% Cu; Ti-6Al-4V+4.0 wt% Cu) and compared the results with those for commercially pure (CP) titanium, Ti-6Al-4V, and gold alloy. Wear testing was performed by repeatedly grinding upper and lower teeth under flowing water in an experimental testing apparatus. Wear resistance was assessed as volume loss (mm(3)) at 5kgf (grinding force) after 50,000 strokes. Greater wear was found for the six types of titanium than for the gold alloy. The wear resistance of the experimental CP Ti+Cu and Ti-6Al-4V+Cu alloys was better than that of CP titanium and Ti-6Al-4V, respectively. Although the gold alloy had the best wear property, the 4% Cu in Ti-6Al-4V alloy exhibited the best results among the titanium metals. Alloying with copper, which introduced the alpha Ti/Ti(2)Cu eutectoid, seemed to improve the wear resistance.

Alloys↗
PubMed2003

EBAG9/RCAS1 expression in hepatocellular carcinoma: correlation with tumour dedifferentiation and proliferation.

The oestrogen-responsive gene, EBAG9, whose product is identical to the cancer cell surface antigen RCAS1, is reported to be associated with tumour progression and invasiveness in various carcinomas. In this study, we examined the expression of EBAG9/RCAS1 in hepatocellular carcinoma (HCC), with special reference to its relationship with the stepwise evolution of HCC. Expression was examined by immunohistochemistry and western blotting analysis in 143 HCCs, as well as in non-cancerous liver tissues. After which, the association between enhanced EBAG9/RCAS1 expression and various clinicopathological parameters including Ki-67 labelling index (LI), a marker of proliferative activity, was evaluated. There was a constant low level of EBAG9/RCAS1 expression in non-cancerous liver tissues, with a regular cytoplasmic distribution. Positive immunoreactivity for EBAG9/RCAS1 was detected on the surface and in the cytoplasm of 84 HCC tumours, with an irregular staining pattern. Enhanced EBAG9/RCAS1 expression was correlated with a lower degree of differentiation and Ki-67 LI. Interestingly, expression was enhanced specifically in the less differentiated lesions within 'nodule-in-nodule' tumours. In conclusion, EBAG9/RCAS1 was associated with HCC tumour dedifferentiation and increased proliferative activity. Its exact functional role remains to be established.

Adolescent↗
PubMed2003

Th1 and Th1-inducing cytokines in Salmonella infection.

Thl and Thl-inducing cytokines and T cell responses were investigated in human salmonellosis. Serum IFN-gamma, IL-12 and IL-18 levels were increased significantly in patients with salmonellosis. The increase in serum IL-15 and IL-18 levels was more significant and prolonged in patients with the systemic form of salmonellosis than in those with the gastroenteric form. The serum IFN-gamma level was correlated significantly with IL-12 and IL18 levels, and the IL-15 level was correlated significantly with IL-18. Upon stimulation with Salmonella in vitro, mononuclear cells from salmonellosis patients produced significantly higher amounts of IFN-gamma and IL-12 compared with those from healthy controls. Anti-IL-12 moAb or anti-IL18 MoAb significantly inhibited Salmonella-induced IFN-gamma production in vitro. gamma delta T cells expressed significantly higher levels of IFN-gamma mRNA in salmonellosis patients than in healthy controls. The results suggest that Th1-inducing cytokines appear to be involved in the in vivo response against Salmonella infection, promoting IFN-gamma production by alpha beta and gamma delta T cells which plays a protective role against Salmonella.

Adolescent↗
PubMed2003

Prognostic value of preoperative serum immunosuppressive acidic protein in patients with esophageal squamous cell carcinoma.

Immunosuppressive acidic protein (IAP) is a potent biological marker of immunological surveillance in patients with malignant tumors. The aim of this study was to analyze the clinicopathologic significance of IAP in patients with esophageal carcinoma. Preoperative serum IAP concentration was measured by enzyme-linked immunosorbent assay in 115 patients with primary esophageal squamous cell carcinomas. The associations between clinicopathologic factors, C-reactive protein (CRP) values and IAP concentration were determined. Prognostic values were determined by multivariate analysis using Cox's proportional hazards model. The IAP concentration is significantly higher in patients with stage II-IV cancers than in those with stage I cancer. Significant differences in IAP concentration were observed depending upon tumor size, tumor depth, lymph node status and CRP values. A high IAP concentration, more than 500 micro g/mL, was an independent prognostic factor. Thus, a high IAP concentration is associated with tumor progression and poor survival in patients with esophageal squamous cell carcinoma.

Aged↗
PubMed2003

Brachial-ankle pulse wave velocity measured automatically by oscillometric method is elevated in diabetic patients with incipient nephropathy.

AIMS: To examine whether brachial-ankle pulse wave velocity (baPWV), a possible early marker of atherosclerotic vascular damage, is associated with albuminuria in patients with Type 2 diabetes. METHODS: BaPWV was measured by automatic oscillometric method in 346 Type 2 diabetic patients with normoalbuminuria (a mean level of three times measurements of albumin-to-creatinine (ACR)<30 microg/mg creatinine; n=200), incipient nephropathy (a mean level of ACR> or =30 and <300 microg/mg creatinine; n=119), and clinical nephropathy (a mean level of ACR> or =300 microg/mg creatinine; n=27), and without peripheral vascular disease. RESULTS: BaPWV (cm/s) was significantly higher in patients with incipient nephropathy (1722 +/- 382) and clinical nephropathy (1763 +/- 322) than in patients with normoalbuminuria (1559 +/- 343, P<0.0001, respectively). By univariate analysis it correlated significantly with age (r=0.44, P<0.0001), systolic blood pressure (r=0.55, P<0.0001), diastolic blood pressure (r=0.42, P<0.0001), albuminuria (r=0.24, P<0.0001) and HbA1C (r=0.11, P<0.05). Albuminuria revealed an independent significant association with baPWV (P<0.01) after adjustment for age, sex, smoking, BMI, HbA1C, hyperlipidemia, and hypertension. Multiple regression analysis showed age, diastolic blood pressure and albuminuria were independently associated with baPWV (adjusted R2=0.42, P<0.0001). CONCLUSIONS: The results might indicate a possible link between the pathogenesis of atherosclerosis and diabetic nephropathy. Future studies are needed to clarify the usefulness and its predictable value.

Aged↗
PubMed2003

Implementation of a redox microarray: an experimental model for future nanoscale biomolecular computing using integrated circuits.

The possibility of constructing high-density parallel computing architectures using molecular electronics technology is explored. By employing molecular computing devices, new circuitsystem integration could be realised. To clarify the proposed concept, an experimental model of a redox microarray is presented. A first experimental system for a redox microarray consists of a two-dimensional array of platinum microelectrodes to catalyse reversible reactions of redox-active molecules. Experimental results of active wave propagation in the redox microarray are presented to demonstrate the potential of molecular computing devices for creating artificially programmable reaction-diffusion dynamics for specific target applications.

Journal Article↗
PubMed2003

Ruptured intercostal artery pseudoaneurysm after blunt thoracic trauma.

Here, we present the case of ruptured intercostal artery pseudoaneurysm two months after blunt thoracic trauma. Ruptured aneurysm hemorrhaged into the retroperitoneal space due to adhesion in the intrathoracic space. We unsuccessfully embolized the aneurysm during an angiographic procedure and performed the aneurysmectomy, removing the hematoma, using a retroperitoneal approach. Ruptured intercostal artery pseudoaneurysm after blunt thoracic trauma may have caused the delayed life-threatening hemorrhage.

Aged↗