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T Ban

Publications and source records attributed to T Ban.

At least 19 recordsLinked to original sources
PubMed2005

Velocity selective optical pumping of Rb hyperfine lines induced by a train of femtosecond pulses.

We present direct observation of the velocity-selective optical pumping of the Rb ground state hyperfine levels induced by 5S(1/2) --> 5P(1/2) femtosecond pulse-train excitation. A modified direct frequency comb spectroscopy based on the fixed frequency comb and a weak cw scanning probe laser was developed. The femtosecond pulse-train excitation of a Doppler-broadened Rb four-level atomic vapor is investigated theoretically in the context of the density matrix formalism and the results are compared with the experiment.

Journal Article↗
PubMed2004

Phylogenetic and evolutionary relationships between Elymus humidus and other Elymus species based on sequencing of non-coding regions of cpDNA and AFLP of nuclear DNA.

Species of the genus Elymus are closely related to some important cereal crops and may thus serve as potential alien genetic resources for the improvement of these crops. E. humidus is indigenous to Japan and is well adapted to a humid climate. However, the phylogenetic and evolutionary relationships between E. humidus and other Elymus species are unclear. To elucidate these relationships, we examined the sequences of three non-coding regions of chloroplast DNA (cpDNA) and the amplified fragment length polymorphism (AFLP) variation of nuclear DNA in E. humidus and other related species. A total of 15 sequence mutations from the three non-coding regions, trnL-trnF, trnF- ndhJ(C), and atpB-rbcL, covering approximately 1,800 bp, were detected in the Elymus species. A phylogenic tree resulting from the cpDNA sequence data revealed that all the species containing the St nuclear genome (St, StH, StY, and StHY) formed a well-supported clade that is remote from the Hordeum species (H). This result strongly supports the finding that Pseudoroegneria is the maternal genome donor to the genus Elymus. In addition, E. humidus showed the closest relationship with the cpDNA genome of the Pseudoroegneria species. The AFLP analysis detected 281 polymorphic bands with 11 AFLP primer combinations. The AFLP result showed that E. humidus is relatively closer to E. tsukushiensis. However, the cpDNA sequencing results indicated that E. humidus and E. tsukushiensis have different cytoplasmic origins. Our results suggest that the evolutionary process between E. humidus and E. tsukushiensis is not monophyletic, although the two species have similar morphological characters and adaptability.

Cell Nucleus↗
PubMed2004

Conversion of AFLP markers associated with FHB resistance in wheat into STS markers with an extension-AFLP method.

Amplified fragment length polymorphism (AFLP) has proven a powerful tool for tagging genes or quantitative trait loci (QTLs) of interest in plants. However, conversion of AFLP markers into sequence-tagged site (STS) markers is technically challenging in wheat owing to the complicated nature of its genome. In this study, we developed an "extension-AFLP" method to convert AFLP markers associated with Fusarium head blight (FHB) resistance into STS markers. When an AFLP marker of interest was detected with an EcoRI+3-MseI+4-selective primer combination, the PCR product was used as a template for an additional selective amplification with four primer pairs, in which one additional selective base (either A, C, G, or T) was added to the 3' end of one of the two primers. The extended primer pair that produced the targeted band was further extended by adding each of the four selective nucleotide bases for the next round of selective amplification. Extension selective amplification was performed until the target bands became clear enough for subsequent cloning and sequencing. By using the extension-AFLP method, we successfully converted two AFLP markers located on chromosome 3BS and associated with FHB resistance into STS markers. Our results indicated that the extension-AFLP method is an efficient approach for converting AFLP markers into STS markers in wheat. The developed STS markers might be used for marker-assisted selection (MAS) for FHB resistance in wheat breeding programs.

Base Sequence↗
PubMed2002

[Multivessel off-pump coronary aortic bypass grafting with an impaired and severely dilated left ventricle using the Starfish heart positioner].

Off-pump coronary artery bypass grafting (OPCAB) is gaining acceptance and is now more widely used for coronary revascularization worldwide. Accessing the vessels, particularly on the lateral and inferior walls of the heart, can sometimes be challenging while the heart is beating, especially in hearts with an impaired and severely dilated left ventricle. The Starfish heart positioner was designed to achieve optimal exposure of the lateral and inferior walls of the heart with minimal hemodynamic compromise. This device was used in a patient with a severely impaired and dilated left ventricle to successfully position the heart for quadruple bypass grafting using all in situ arterial grafts, such as bilateral international thoracic arteries (ITAs) and the right gastroepiploic artery. The degree of hematoma caused by the pressure of the suction cup of this device was minimal. This case report suggests that the use of Starfish heart positioner will facilitate and expand the ability of surgeons to easily and consistently perform OPCAB.

Coronary Artery Bypass↗
PubMed2001

Enhancement of phase separation using a drop coalescer in an aqueous two-phase system.

The effect of a drop coalescer on phase separation in a PEG/salt aqueous two-phase system (ATPS) in the absence and presence of protein has been investigated. Raschig rings of ceramic, PTFE and glass were used as a drop coalescer in order to separate the mixture into two phases. Among the three materials PTFE is the most effective in coalescing the dispersed drops, with the throughput with PTFE being twice that without the coalescer. Random packing gives good results for phase separation. Two types of fiber mesh coated with PTFE were also used as drop coalescers, one in a spirally folded form and the other in a three-dimensional lattice-form. Throughput in the PEG/salt system with the three-dimensional lattice-form is 1.2 times as high as that with the spirally folded form. Throughput with the coalescer formed by compiling PTFE Raschig rings and fiber mesh in lattice form is 1.6 and 1.2 times as high as the case of separate use of the fiber mesh and the PTFE Raschig rings, respectively. The hydrophobic surface of PTFE in the compiled coalescer has no significant effect on the recovery fraction of the protein in ATPS.

Adsorption↗
PubMed2001

Surgically treated aortic root aneurysm following aortic valve replacement.

A 65-year-old man with aortic regurgitation underwent aortic valve replacement with a St. Jude Medical prosthetic valve about 6 years ago. At that time, the aortic root was slightly dilated at about 40 mm in diameter and the ascending aorta was within the normal range. This year, the man was diagnosed with an aortic root aneurysm in regular follow-up echocardiography. Chest-enhanced computed tomography and chest aortography at our hospital demonstrated a pear-like aortic root aneurysm about 60 mm in diameter. Elective operation for the aortic root aneurysm was conducted September 29, 1999, based on the Bentall procedure. Composite graft replacement with coronary reconstruction was conducted using a 28-mm Hemashield prosthetic graft and a 23-mm St. Jude Medical prosthetic valve under cardiopulmonary bypass. An 8-mm Hemashield graft was interposed on the left main coronary artery and the right coronary artery was directly anastomosed using a Carrel patch method. The postoperative course was uneventful and post-operative examination demonstrated good surgical results. Histological findings of the aortic aneurysm wall showed cystic medial necrosis. Surgical cases of aortic root aneurysm after aortic valve replacement are rare, but serious complications with the possibility of rupture or dissection warrant surgical intervention.

Aged↗
PubMed2001

Coexistence of lung cancer and hamartoma.

We present a rare case of a synchronous primary lung cancer adjacent to a hamartoma. A 71-year-old woman was admitted with congestive heart failure due to acute myocardial infarction. A chest radiogram on admission showed pulmonary edema with a tumor shadow in the right upper lung field. Because histological diagnosis was not obtained preoperatively, a wedge resection of the lung was conducted using video-assisted thoracoscopic surgery. The histopathological examination confirmed the coexistence of an adenocarcinoma with a chondromatous hamartoma. Right upper lobectomy was performed followed by excision of the mediastinal lymph nodes. Although hamartoma is generally considered to be a benign neoplasm, there have been several reports of increased risk to lung cancer in patients with a chondromatous hamartoma. Therefore, we recommend that patients with a hamartoma should be submitted to a complete evaluation and to regular follow-up, considering the risk to associated synchronous malignancy.

Adenocarcinoma↗
PubMed2001

Identification of GFAT1-L, a novel splice variant of human glutamine: fructose-6-phosphate amidotransferase (GFAT1) that is expressed abundantly in skeletal muscle.

Glutamine:fructose-6-phosphate amidotransferase (GFAT1) is the rate-limiting enzyme in the hexosamine biosynthetic pathway, which plays an important role in hyperglycemia-induced insulin resistance. To evaluate the role of GFAT1 expression, we analyzed the expression profiles of GFAT1 mRNA in various human tissues using reverse transcriptase-polymerase chain reaction. We report here the identification and cDNA cloning of a novel GFAT1 splice variant expressed abundantly in skeletal muscle and heart. This subtype, designated GFAT1-L, contains a 54-bp insertion within the GFAT1 coding sequence. Recombinant GFAT1-L protein possessed functional GFAT activities and biochemical characteristics similar to GFAT1. Previously, GFAT1 was considered a simplex enzyme. The identification of a novel GFAT1 subtype possessing functional enzymatic activity and tissue-specific expression should provide additional insight into the mechanism of skeletal muscle insulin resistance and diabetes complications.

Alternative Splicing↗
PubMed2001

Changes in ultra-low and very low frequency heart rate variability after coronary artery bypass grafting.

This study was performed to assess the effects of coronary artery bypass grafting (CABG) on the ultra-low (ULF) and very low (VLF) frequency components of heart rate variability (HRV). Forty-nine CABG patients (aged from 38 to 77 years) were examined by 24-h ambulatory electrocardiographic (AECG) monitoring, both preoperatively and 4 weeks after CABG. HRV spectral components were obtained by maximum entropy method analysis. Then the ULF, VLF, low frequency (LF), high frequency (HF) and total frequency (TF) components were compared before and after CABG. The average 24-h heart rate increased significantly after CABG (69+/-11.5 vs 82.9+/-10.9 beats per minute [bpm], P < 0.0001). The power of the ULF, VLF, and LF spectral components showed a decrease after surgery (2,859.9 vs 1,601.2 ms2, P<0.0001, 1,215.0 vs 572.3 ms2, P<0.0001, and 260.3 vs 125.9 ms2, P< 0.002, respectively), but the HF power did not show any significant change (98.7 vs 125.9 ms2, NS). Analysis of the normalized ratio of the ULF component (ULF/TF ratio) revealed a significant increase postoperatively (0.6496+/-0.0931 vs 0.7003+/-0.1338, P < 0.0001), but the VLF/TF and LF/TF ratios decreased after CABG (from 0.2671+/-0.0689 to 0.2040+/-0.0832, P< 0.0001 and from 0.0568+/-0.0290 to 0.0429+/-0.0232, P< 0.0088, respectively). In contrast, there was no significant alteration in the HF/TF ratio. These results suggest that recovery of cardiac autonomic activity is delayed after surgery. However, improvement of the ULF/TF ratio, one of the prognostic indicators for patients with cardiac disease, should be related to the relief of myocardial ischemia by CABG.

Aged↗
PubMed2001

The effects of chromosomes 3A and 3B on resistance to Fusarium head blight in tetraploid wheat.

Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive diseases of wheat in areas where the weather is warm and humid after heading. Previous studies indicate that the level of resistance to FHB varies not only among wheat cultivars but also among some of their wild relatives. No accession, however, has yet been identified to be completely immune to FHB among the Gramineae. It is known that durum wheat (Triticum turgidum L. conv. durum) is consistently more susceptible to FHB than common wheat (T. aestivum L.). The importance of the D genome in conferring resistance to FHB has been emphasized. Meanwhile, recent studies using molecular markers report effective QTLs on chromosome 3BS in a hexaploid population and on 3A in tetraploid recombinant inbred chromosome lines. In this study, we performed an evaluation of the effects of homoeologous group 3 chromosomes of T. turgidum ssp. dicoccoides on resistance to FHB using a set of chromosome substitution lines of a durum wheat cultivar 'Langdon'. The accession of T. turgidum ssp. dicoccoides examined in this study was more susceptible for Type II resistance (resistance to spread of FHB in the head) than 'Langdon'. Both of the chromosome substitution lines of 3A and 3B showed the same level of resistance with 'Langdon', but bleaching of the heads was completely prevented in the substitution lines of chromosome 3A without relationship to rachis fragility. It was concluded that the chromosome 3A of T. turgidum ssp. dicoccoides carries resistance gene(s) to head bleaching caused by FHB.

Chromosomes↗
PubMed2001

[The effect of celiprolol hydrochloride for lipid metabolism--especially for the low density lipoprotein particle size].

Recently, much attention has been paid to small sized low density lipoprotein (LDL) as a risk factor for ischemic heart disease. We investigated the effect of celiprolol hydrochloride (CH), which is a beta 1 selective beta-blocker with high intrinsic sympathomimetic activity (ISA), on the LDL particle size. We treated 41 hypertensive patients with CH and studied the change in LDL particle size according to the score of fast beta lipoprotein and LDL relative mobility value (LDL-Rm) measured by lipoprotein polyacrylamide gel disc electrophoresis (PAGE). We also studied changes in blood pressure, total cholesterol (TC), trygiyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and midband on PAGE. Systolic and dyastolic blood pressure and pulse significantly decreased during treatment. TC levels were significantly decreased at 8 weeks in all subjects and at 4, 8 and 12 weeks in patients with a TC value of over 220 mg/dl. TG levels were significantly decreased at 4 and 8 weeks in patients with initial levels of over 150 mg/dl, and significantly increased at 4 and 8 weeks in those with initial levels of under 150 mg/dl of TG. HDL-C levels did not significantly change during treatment. LDL-C levels were significantly decreased at 4, 8 and 12 weeks in patients with initial levels of over 150 mg/dl. Apo AI, AII, B, CII, CIII and E levels did not significantly change during treatment. Fast beta lipoprotein scores did not significantly change overall during treatment, but were significantly decreased at 4 and 8 weeks in patients initial TG levels of over 150 mg/dl and at 4 and 12 weeks in those with initial levels of over 220 mg/dl of TC. LDL-Rm scores did not significantly change during treatment. Midband scores were significantly reduced overall at 8 weeks, and after 4 and 8 weeks in patients with initial TG levels of over 150 mg/dl and at 4, 8 and 12 weeks in those with initial TC levels of over 220 mg/dl. These results indicated that CH did not change LDL particle size. It was suggested that CH might be a beneficial beta-blocker from the standpoint of prevention for atherosclerosis.

Aged↗
PubMed2001

[Inferior mini-sternotomy for off-pump CABG using bilateral internal thoracic arteries].

Case 1: A 72-year-old woman with effort angina underwent coronary artery bypass grafting. A preoperative coronary angiogram showed 90% stenosis in the proximal main RCA, and total occlusion in the proximal LAD, distal of which was an area well supplied by collaterals from the RCA. This patient had previously undergone right upper lobectomy due to lung cancer. With a skin incision of 8 cm, the LITA was inserted into the LAD and the RITA was inserted into the mid RCA through an inferior mini-sternotomy while the heart was beating. Case 2: A 69-year-old man with effort angina underwent CABG. A preoperative coronary angiogram showed 90% stenosis in the proximal main RCA, 75% stenosis in the PDA and total occlusion in the proximal LAD, distal of which was an area well supplied by collaterals from the RCA. With a skin incision of 11 cm, the LITA was inserted into the LAD, the RITA into the mid-RCA and the radial artery graft attached to the RITA was grafted to the PDA through an inferior mini-sternotomy while the heart was beating. In both cases, the sternum was not cut transversely in order to prevent injury to the ITAs and pseudo-joint formation. With the use of this technique, exposure of the LAD and RCA was excellent. Postoperative recovery in both patients was uneventful and postoperative angiograms revealed widely patent grafts. This technique was very useful when performing off-pump CABG using bilateral ITAs.

Aged↗
PubMed2001

[Coronary artery bypass-grafting using interrupted anastomosis with the U-clip].

For coronary artery anastomosis, the continuous suture technique is generally used because it is easy to perform, there is less anastomotic leakage, and a shorter anastomotic time compared with the interrupted suture technique. However, with this technique there is a potential risk of anastomotic stenosis caused by the purse-string effect, which does not occur with the interrupted suture technique. The U-Clip device was designed to facilitate the interrupted suture technique in coronary anastomosis by eliminating the need for suture management, knot tying, and surgical assistance. The device employs the superelastic properties of nitinol and two components: 1. a needle/suture delivery system, and 2. a detachable nitinol self-closing wire. We used this device successfully for LITA-LAD anastomosis in MIDCAB. When this device is applied to small caliber conduits, such as the internal thoracic arteries and the gastroepiploic artery, the side-to-side anastomosis can reduce the anastomotic leakage more efficiently, since the coronary incision and graft incision can be perfectly matched. The U-Clip facilitates coronary anastomosis by simplifying and decreasing the amount of manipulation and complexity required in minimally invasive CABG procedures. Nitinol technology also has potential in robotic and endoscopic surgical applications.

Aged↗
PubMed2000

Tricuspid valve replacement after cardiac transplantation.

Tricuspid regurgitation, a fairly common finding after cardiac transplantation, is generally mild or moderate, and is not clinically significant. The etiology of tricuspid regurgitation is not entirely understood, and experience with valve replacement after cardiac transplantation is limited. We describe a case of progressively severe tricuspid regurgitation ultimately requiring tricuspid valve replacement. At operation, the ruptured chordae of the posterior part of anterior and septal leaflet with resulting partially flail leaflets were found. Examination of the papillary muscle showed origins of several of the ruptured chordae. Damage to the tricuspid subvalvular apparatus at endomyocardial biopsy appeared to be a possible cause. A 31-mm Carpentier-Edwards porcine valve was implanted. This was because replacement with a mechanical prosthesis would prevent future right-side heart catheterization and endomyocardial biopsy and in valve repair, the patient remains exposed to the risk of the recurrence of chordal rupture. We discuss proposed causes and choices in surgical technique.

Adult↗
PubMed2000

Twenty-two-year follow-up of saphenous vein grafts in pediatric Kawasaki disease.

We describe 2 Kawasaki disease patients with excellent long-term patency of saphenous vein grafts, who underwent coronary artery bypass at age 7 and 9 years, respectively, and demonstrated normal growth during 22 years of follow-up. The grafts showed no deterioration and played an important role in coronary blood supply.

Child↗
PubMed1999

Preparation of a Completely Oriented Molecular Sieve Membrane.

Growth of oriented seed crystals on a substrate led to a completely oriented and continuous membrane of LTA-type zeolite. The seed crystals of cubic morphology were dip-coated onto a tilted substrate (see schematic diagram) with the zeolite channels normal to the surface. The substrate was hydrothermally treated in a reaction mixture containing the organic ligand 2,2-bis(hydroxymethyl)-2,2',2"-nitrilotriethanol, which lowers the degree of supersaturation of [Al(OH)(4)](-) ions and preferentially facilitates the intergrowth of the seed crystals.

Journal Article↗
PubMed1999

Reactive oxygen species play an important role in the activation of heat shock factor 1 in ischemic-reperfused heart.

BACKGROUND: The myocardial protective role of heat shock protein (HSP) has been demonstrated. Recently, we reported that ischemia/reperfusion induced a significant activation of heat shock factor (HSF) 1 and an accumulation of mRNA for HSP70 and HSP90. We examined the role of reactive oxygen species (ROSs) in the induction of stress response in the ischemic-reperfused heart. METHODS AND RESULTS: Rat hearts were isolated and perfused with Krebs-Henseleit buffer by the Langendorff method. Whole-cell extracts were prepared for gel mobility shift assay using oligonucleotides containing the heat shock element. Induction of mRNA for HSP70 and HSP90 was examined by Northern blot analysis. Repetitive ischemia/reperfusion, which causes recurrent bursts of free radical generation, resulted in burst activation of HSF1, and this burst activation was significantly reduced with either allopurinol 1 mmol/L (an inhibitor of xanthine oxidase) or catalase 2x10(5) U/L (a scavenger of H2O2). Significant activation of HSF1 was observed on perfusion with buffer containing H2O2 150 micromol/L or xanthine 1 mmol/L plus xanthine oxidase 5 U/L. The accumulation of mRNA for HSP70 or HSP90 after repetitive ischemia/reperfusion was reduced with either allopurinol or catalase. CONCLUSIONS: Our findings demonstrate that ROSs play an important role in the activation of HSF1 and the accumulation of mRNA for HSP70 and HSP90 in the ischemic-reperfused heart.

Allopurinol↗