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T Akiba

Publications and source records attributed to T Akiba.

At least 91 records · Page 5Linked to original sources
PubMed1996

[Surgical experiences of fenestrated total cavopulmonary connection in patients under four year of age].

The fenestrated Fontan operation is an interim steps for patients who considered to be at high risk for one step Fontan procedure. We performed total cavopulmonary connection with baffle fenestration in five patients under four year of age (33 month of mean age at operation). All patients previously underwent palliative surgery (Blalock shunt in 3, PA banding in 2). Three patients weighed less than 10 kg. Pulmonary vascular resistance index (PARI) were 2.03 +/- 0.18 U/BSA and exceeded 2 U/SQm in 3 patients. Nakata's indice were ranged from 282 to 644 (mean 394) mm2/BSA. Bidirectional cavopulmonary shunt was considered to be alternative pathway for three patients in staged Fontan strategy. Postoperative hemodynamics were relatively stable in all patients and weaned from mechanical ventilation within 5 days with various arterial oxygen saturation. There was no pleural effusion lasting longer than 1 week. One patient died of ileus caused from congenital malrotation. Follow up catheter examination at 1 year showed 83 to 96% of SaO2 and survived patients were doing well. Fenestrated TCPC can be applied safely in younger patients who are considered to need surgical treatments in staged Fontan strategy. Whether fenestration should be closed has to be wait further studies.

Age Factors↗
PubMed1995

Separation of bacterial cells by free flow electrophoresis under microgravity: a result of the SpaceLab-Japan project on Space Shuttle flight STS-47.

We demonstrated free flow electrophoresis (FFE) of charged cells under microgravity, where gravitational effects are almost eliminated. Separation of a mixture of three bacterial strains (mutants of Salmonella typhimurium LT2) by FFE was conducted on NASA Space Shuttle flight STS-47 (September 1992). The experiment was designed to differentiate three strains having different lipopolysaccharide core structures in the cell membrane. The results were compared to those of ground experiments, in order to examine whether or not FFE in a weightless environment provides distinct advantages. Smooth strain SL1027 and rough strain SL3749 migrated to two separated fractions. The quality (viability) and the yields of the separated samples were sufficient to show the advantage of microgravity. Another rough strain, SL1102, exhibited unexpected electrophoretic behavior, which prevented the complete resolution of the three strains. All the strains were recovered as viable cells after 8 days of flight. The present study suggests that electrophoretic separation of bacterial cells is much more effective under microgravity conditions with relatively good resolution in comparison with the ground operation.

Anti-Bacterial Agents↗
PubMed1995

Laparoscopic mesenterioadhesiotomy and Tenckhoff catheter placement in patients with predisposing abdominal surgery.

Peritoneoscopic surgery has been performed widely for a variety of abdominal surgical diseases. We describe here a safe and reliable technique of laparoscopic-assisted mesenterioadhesiotomy and peritoneal Tenckhoff catheter placement in patients who have previously undergone abdominal surgery. Five patients suffering from end-stage renal failure previously underwent single and/or polyabdominal surgery. The surgical procedures included hysterectomy, ovarian resection, appendectomy, and transabdominal right nephrectomy. Under general endotrachial anesthesia, a laparoscope was placed down through a direct cut made using a trocar. After CO2 gas insufflation, another one or two trocars were put in place for surgical procedures. To avoid intestinal injury, mesenterioadhesiotomy was performed carefully using a high-frequency hook electrode, forceps, and scissors forceps, and the Tenckhoff catheter was subsequently inserted with forceps directly into Douglas' fossa. Peritoneal equilibration tests performed 30-70 days after the initiation of continuous ambulatory peritoneal dialysis (CAPD) treatment revealed moderate to good peritoneal effectiveness. This procedure permits the surgeon to perform safe and exact catheter placement into Douglas' fossa even when there is a possibility that peritoneal and mesenterial adhesion are present. We believe that this technique of catheter placement may extend the indication for CAPD treatment in patients with predisposing lower abdominal surgery.

Aged↗
PubMed1995

Effects of recombinant human erythropoietin and exercise training on exercise capacity in hemodialysis patients.

The effects of recombinant human erythropoietin (rHuEPO) and exercise training on exercise capacity were evaluated in 20 hemodialysis patients. After improvement of anemia by rHuEPO (Phase I), patients were divided into 2 groups. Group 1, 10 patients, was placed in a 3-month exercise training program. Group 2, 10 patients, served as a control group (Phase 2). A symptom-limited exercise tolerance test was performed at the start of Phase 1 and before and after Phase 2. Hemoglobin (Hb) values were kept constant throughout Phase 2. In Phase 1, maximum workloads (62.0 +/- 19.1 to 76.5 +/- 25.6 W, p < 0.001), maximum O2 uptake (VO2max) (18.7 +/- 3.5 to 2.2 +/- 5.9 ml/min/kg, p < 0.01), and VO2 at anaerobic threshold (AT) (VO2AT) (8.5 +/- 2.1 to 10.2 +/- 2.9 ml/min/kg, p < 0.01) were all improved by rHuEPO. However, in Phase 2, despite unchanged Hb values and maximum workloads, VO2max (20.7 +/- 4.6 to 17.6 +/- 2.6 ml/min/kg, p < 0.05) and VO2AT (10.6 +/- 1.4 to 9.5 +/- 1.8, ml/min/kg p < 0.05) were decreased in Group 2. However, in Group 1, maximum workloads (66.7 +/- 8.2 to 81.7 +/- 7.5 W, p < 0.01) were improved, and VO2max and VO2AT were not decreased significantly in the same period. Exercise training in rHuEPO-treated hemodialysis patients resulted in an improved aerobic exercise capacity, whereas those without exercise training did not have increased capacity. Throughout the study, O2 uptakes were lower than those of nonrenal anemic patients who had similar Hb values. Maximum lactate values also remained low. In conclusion, improvement in the exercise capacity in hemodialysis patients treated with rHuEPO was minimal. Some defects were suggested in the aerobic energy production system in skeletal muscle of dialysis patients. Anemia-improved patients should participate in incremental physical activity to maintain an improved exercise capacity.

Adult↗
PubMed1995

Purification and Properties of Extracellular Amylase from the Hyperthermophilic Archaeon Thermococcus profundus DT5432.

A hyperthermophilic archaeon, Thermococcus profundus DT5432, produced extracellular thermostable amylases. One of the amylases (amylase S) was purified to homogeneity by ammonium sulfate precipitation, DEAE-Toyopearl chromatography, and gel filtration on Superdex 200HR. The molecular weight of the enzyme was estimated to be 42,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amylase exhibited maximal activity at pH 5.5 to 6.0 and was stable in the range of pH 5.9 to 9.8. The optimum temperature for the activity was 80(deg)C. Half-life of the enzyme was 3 h at 80(deg)C and 15 min at 90(deg)C. Thermostability of the enzyme was enhanced in the presence of 5 mM Ca(sup2+) or 0.5% soluble starch at temperatures above 80(deg)C. The enzyme activity was inhibited in the presence of 5 mM iodoacetic acid or 1 mM N-bromosuccinimide, suggesting that cysteine and tryptophan residues play an important role in the catalytic action. The amylase hydrolyzed soluble starch, amylose, amylopectin, and glycogen to produce maltose and maltotriose of (alpha)-configuration as the main products. Smaller amounts of larger maltooligosaccharides were also produced with a trace amount of glucose. Pullulan; (alpha)-, (beta)-, and (gamma)-cyclodextrins; maltose; and maltotriose were not hydrolyzed.

Journal Article↗
PubMed1995

A hyperthermophilic sulfur-reducing archaebacterium, Thermococcus sp. DT1331, isolated from a deep-sea hydrothermal vent.

A hyperthermophilic archaebacterium was isolated from a deep-sea black smoker chimney (depth, 760 m) at the Minami-ensei Knoll (28 degrees 23'N, 127 degrees 38'E). The strain, designated DT1331, was a coccoid shaped bacterium about 0.5 to 1.0 microns in diameter. The cells were surrounded by a cell envelope. The temperature for growth was between 55 degrees C and 93 degrees C with an optimum 80 degrees C. The growth occurred from pH 4.5 to 8.5 and the optimum pH was 6.0. DT1331 required 1% to 5% NaCl for growth and cell lysis was observed below 1% NaCl concentration. The strain was an anaerobic chemoorganotroph requiring elemental sulfur obligately. Organic substrates used included tryptone, peptone, soytone, casein, gelatin, and yeast extract. Under the optimal conditions, DT1331 had a generation time of 50 min and could reach densities of about 1.5 x 10(8) cells/ml. DT1331 was resistant to ampicillin, chloramphenicol, erythromycin, kanamycin, streptomycin, and tetracycline, which was one of the common characteristics of archaebacteria. The G+C content of DT1331 was 52.3 mol%. Analysis of the 16S rRNA gene by restriction enzymes coincided with those of Thermococcus celer, indicating that this strain belonged to the genus Thermococcus.

Anti-Bacterial Agents↗
PubMed1995

Purification and characterization of a new lipase from Fusarium sp. YM-30.

The extracellular lipase from Fusarium sp. YM-30 was purified by a procedure involving ultrafiltration, ammonium sulfate precipitation, and DEAE-Toyopearl 650M, CM-Toyopearl 650M, and Butyl-Toyopearl 650M column chromatographies. The purified lipase was homogeneous with 12kDa of molecular mass by SDS-PAGE, and had high specificities for mono- and diacylglycerols, but low toward triacylglycerols. The enzyme had maximum activity at pH 7.0 to 8.0 and 37 degrees C, and hydrolyzed digalactosyl diglyceride too.

Animals↗
PubMed1995

[Morphological study on the gastric mucosa in diabetes mellitus rats induced by streptozotocin].

To clarify the pathogenesis of vulnerability to acute gastric mucosal lesion (AGML) in diabetes mellitus (DM), we investigated histopathologically the gastric mucosa of the fundic gland in streptozotocin-induced DM rats. The length of the mucosa and the thickness of the surface epithelial cell (SEC) layer were measured, and the number of proliferating cell nuclear antigen (PCNA) positive cells was counted. As results, compared with control rats, the ratio of the length of SEC layer to that of mucosa, and the number of PCNA positive cells were significantly decreased in DM rats, whereas the length of the mucosa tended to extend in DM rats. Consequently, it is considered that attenuation of mucosal barrier in the SEC layer can be closely associated with susceptibility to occurrence of AGML in DM.

Animals↗
PubMed1995

Angiographic determination of left and right ventricular volumes and left ventricular mass in normal infants and children.

Left and right ventricular (LV and RV) volumes and LV mass were assessed by angiography in 63 infants and children without major cardiovascular abnormalities. LV and RV end-diastolic volumes (EDV) were excellently expressed as a function of body surface area (BSA) with an exponential equation: LVEDV = 83.7 (BSA)1.29 ml (r = 0.96, p < 0.001), RVEDV = 87.9 (BSA)1.29 ml (r = 0.94, p < 0.001). LV ejection fraction (EF) averaged 64 +/- 6 (mean +/- standard deviation) %, and RVEF 56 +/- 5%, each of which was independent of BSA. LV mass was well expressed as a function of BSA with an exponential equation: LV mass = 75.4 (BSA)1.22 g (r = 0.86, p < 0.001). LV mass/LVEDV was constant, and averaged 0.96 +/- 0.22 g/ml. Thus, the values of LVEDV, RVEDV, and LV mass in infants and children with various heart diseases may be estimated with reasonable accuracy as a percentage of normal values predicted from their BSA by using the above-proposed exponential equations. The normal values of LVEF, RVEF and LV mass/LVEDV themselves can be compared with these parameters in pediatric patients with heart diseases because of their independence of BSA.

Adolescent↗
PubMed1995

[A case of pentalogy of Cantrell with tetralogy of Fallot and left ventricular diverticulum].

We report a successful repair of tetralogy of Fallot and left ventricular diverticulum associated with pentaology of Cantrell. The repair consisted of partial infundibular septectomy, closure of ventricular septum, reconstruction of right ventricular outlet using monocuspid transjunctional patch, and resection of left ventricular diverticulum. The infundibulum was extremely elongated, caused by ventricular dextroversion, and the hypoplasia of pulmonary trunk was absent. Therefore, transjunctional patch was longer, even after infundibular septectomy. This report discuss the pathogenesis of these cardiac anomalies and surgical imlication.

Abnormalities, Multiple↗
PubMed1995

Intravenous calcitriol can increase bone mass in hemodialysis patients with osteitis fibrosa.

Intravenous calcitriol administration (IVC) suppressed parathyroid hormone (PTH) secretion and improved osteitis fibrosa (OF) in long-term hemodialysis (HD) patients, although it did not increase the mineralized bone area or the mineral apposition rate. We observed the long-term effects of IVC on OF in 8 HD patients. Bone biopsy of 7 patients revealed increased bone turnover and decreased bone mass. One microgram of calcitriol was given intravenously three times weekly after each HD session for 12 months. The dose was adjusted to maintain the serum corrected calcium level at < 11.5 mg/dl. Dual-energy X-ray bone absorptiometry (DEXA), 3rd lumbar vertebra bone density by quantitative computed tomography (QCT), and biochemical data were taken before IVC, and after 6 and 12 months of IVC. Seven HD patients were given 0.5 microgram/day 1 alpha-cholecalcitriol as controls. The serum corrected calcium levels were 9.9 +/- 0.3 (mean +/- SE) and 11.1 +/- 0.2 mg/dl at 0 and 12 months, respectively (p = 0.06). The serum phosphate levels were 6.2 +/- 0.7 and 6.6 +/- 0.6 mg/day at 0 and 12 months, respectively (p = 0.56). The serum intact PTH levels were 928 +/- 281 and 617 +/- 192 (p = 0.016) at 0 and 12 months, respectively. The bone mass of the 3rd lumbar vertebra measured by QCT was 195 +/- 17 and 218 +/- 186 g/cm3 at 0 and 12 months, respectively (p = 0.156). The bone mass of the trunk measured by DEXA was 660 +/- 44 and 706 +/- 32 g and 0 and 12 months, respectively (p = 0.156). These parameters did not change in controls. Sequential bone biopsy in 3 cases also supported these changes. We conclude that IVC not only suppresses bone turnover, but that it also restores decreased bone mass in HD patients with OF.

Adult↗
PubMed1995

[Uptake of Tc-99m hexakis 2-methoxy isobutyl isonitrile in lung or mediastinal lesions by SPECT].

The uptake of Tc-99m hexakis 2-methoxy isobutyl isonitrile (99mTc-MIBI) was evaluated in 18 patients with various lung or mediastinal lesions by SPECT. The patients consisted of seven with lung cancers, three with lung cancers who were treated with chemotherapy and were disease free, and one each with malignant lymphoma, esophageal cancer, thyroid cancer involving the mediastinum, malignant thymoma, pneumonia, granuloma, sarcoidosis and neurinoma. SPECT imaging (30 min, 600 MBq) was performed after intravenous injection. Strong uptake of 99mTc-MIBI was noted in all malignant tumors except malignant lymphoma. The mean tumor to normal lung tissue uptake ratio (T/N ratio) was 2.26. The mean in lung cancer was 2.31. Slight accumulation was present in pneumonia and granuloma (mean T/N = 1.24). No accumulation was present in a case of non-Hodgkin's lymphoma and neurinoma. Moderate uptake was noted in one case of sarcoidosis (T/N = 1.46). No abnormal accumulation of 99mTc-MIBI was seen in post-therapeutic lung cancer. These results suggested that 99mTc-MIBI SPECT could be useful in differentiating between malignant and benign lesions.

Adult↗
PubMed1995

Effects of one-year cadmium exposure on livers and kidneys and their relation to glutathione levels.

To study the effects of a long-term cadmium exposure on livers and kidneys, rats were administered cadmium chloride (0.228 mg Cd/kg, 3 days/week ip), for one year. Significant accumulation of cadmium was observed in livers (183 +/- 40 micrograms/g liver) and kidneys (92 +/- 17 micrograms/g kidney). Serum urea nitrogen and creatinine levels were significantly elevated in the cadmium-treated rats, while liver function tests were minimally affected. Histological observations showed interstitial fibrosis with minimal cell necrosis and inflammatory cell infiltration in livers, and apparent degeneration of proximal tubules and infiltration of inflammatory cells in parenchyma of kidneys. Lipid peroxidation in livers and kidneys, as assessed by thiobarbituric acid reactive substances, revealed no differences between the cadmium-treated rats and the controls. Glutathione contents were significantly increased in the cadmium treated rats both in livers (p < 0.001), and in kidneys (p < 0.001) compared with the controls. Increased glutathione levels in livers may contribute, in part, to the prevention of serious hepatotoxicity during chronic cadmium exposure, while nephrotoxicity due to cadmium may not be prevented by glutathione.

Animals↗
PubMed1995

[Body surface isopotential T map and ventricular volume characteristics in secundum atrial septal defect].

Body surface isopotential T map was analyzed to detect right ventricular volume and pressure overloads in 25 patients with secundum atrial septal defect. Three patterns were distinguished: the T map resembling normal (type A, n = 9); that with isolated negative area in positive area (type B, n = 11); and that with rightward movement of maximum (type C, n = 5). Right ventricular end-diastolic volumes in type B (161 +/- 19% of normal; %N) and C (175 +/- 40% N) were significantly (p < 0.01) greater than those in control (100 +/- 9% N) and type A (113 +/- 18% N). Right ventricular systolic pressure in type C (48 +/- 11 mmHg) was significantly (p < 0.01) higher than those in control (30 +/- 5 mmHg), type A (31 +/- 4 mmHg) and type B (34 +/- 5 mmHg). These results suggest that the cases with type B have right ventricular volume overload, and those with type C have both volume and pressure overloads.

Body Surface Potential Mapping↗
PubMed1995

Plasma human brain natriuretic peptide in chronic renal failure.

Brain natriuretic peptide (BNP) is a polypeptide hormone which is homologous with atrial natriuretic peptide (ANP). Since the 2 hormones partially share common secretory regulation we simultaneously assessed plasma BNP and ANP in patients with chronic glomerulonephritis without apparent cardiac involvement. Blood samples were taken from patients with serum creatinine (Cr) 0.5-1.2 mg/dl (normal renal function), patients with Cr > 1.2 mg/dl (chronic renal failure) and dialysis patients. BNP did not correlate with serum Cr, which indicated our antibody did not recognize accumulated metabolites due to decreased renal function. BNP and ANP decreased after dialysis-(p < 0.01). Changes of BNP during HD correlated with changes in body weight (p < 0.05). Plasma BNP concentrations were 12.0 +/- 22.0 pg/ml in patients with normal renal function, 17.6 +/- 23.4 pg/ml in chronic renal failure, and 91.5 +/- 93.5 in dialysis patients (p < 0.05 compared with patients with normal renal function). Plasma BNP/ANP ratios were 0.507 +/- 0.646 in patients with normal renal function, 0.392 +/- 0.842 in chronic renal failure, and 0.573 +/- 0.431 in dialysis patients (p < 0.05, compared with chronic renal failure). Increased ANP in chronic renal failure and dialysis indicates volume overload on atrium. In contrast, BNP increased only in dialysis patients, which indicates differences of hemodynamic stress in chronic renal failure and dialysis. We conclude that simultaneous measurements of plasma BNP and ANP further discriminate salt-water and hemodynamic abnormalities in dialysis patients.

Adult↗
PubMed1994

Endobronchial metastasis from a primary uterine osteosarcoma in a patient with multiple myeloma: report of a case.

We present herein the case of a 75-year-old woman with multiple myeloma who underwent a left lower lobectomy for endobronchial metastasis from an uterine osteosarcoma. She had initially been admitted to our hospital for chemotherapy more than 1 year earlier, soon after which a primary uterine osteosarcoma was discovered and a total abdominal hysterectomy and bilateral salpingo-oophorectomy performed. One year after the operation, the patient developed hemoptysis. A flexible bronchofiberscopy demonstrated a polypoid mass obstructing the left basal bronchus, and computed tomographic scans showed three pulmonary nodules. Surgery was performed to control the hemoptysis. At thoracotomy, two metastatic nodules were identified in the left lower lobe, and the endobronchial extension of the tumor was resected en bloc with the left lower lobe. The tumor was diagnosed as lung metastasis from the uterine osteosarcoma. Although further lung tumors have recently appeared, the patient has remained well for the 3 years since her last operation without any hemoptysis.

Aged↗