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Biomedical subjects

I Tabata

Publications and source records attributed to I Tabata.

At least 55 records · Page 3Linked to original sources
PubMed1990

Effect of physical training on the responses of serum adrenocorticotropic hormone during prolonged exhausting exercise.

The purpose of this study was to investigate the effects of physical training on the responses of serum adrenocorticotropic hormone (ACTH) and cortisol concentration during low-intensity prolonged exercise. Five subjects who had fasted for 12 h cycled at the same absolute intensity that elicited 50% of pre-training maximal oxygen uptake (VO2max), either until exhaustion or for up to 3 h, before and after 7 weeks of vigorous physical training [mean daily energy consumption during training exercise, 531 kcal (2230 kJ)]. In the pretraining test, serum ACTH and cortisol concentrations did not increase during the early part of the exercise. Increases in concentrations of both hormones occurred in all subjects when blood glucose concentration decreased during the later phase of the exercise. The mean values and SEM of serum ACTH and cortisol concentrations at the end of the exercise were 356 ng.l-1, SEM 79 and 438 micrograms.l-1, SEM 36, respectively. After the physical training, VO2max of the subjects improved significantly from the mean value of 50.2 ml.kg-1.min-1, SEM 2.5 to 57.3 ml.kg-1.min-1, SEM 2.0 (P less than 0.05). In the post-training test, exercise time to exhaustion was prolonged in three subjects. Comparing the pre- and post training values observed after the same length of time that the subjects had exercised in the pre-training test, the post-training values of serum ACTH (44 ng.l-1, SEM 3) and cortisol (167 micrograms.l-1, SEM 30) concentration were less than the pre-training value (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed1990

Effect of high-intensity endurance training on isokinetic muscle power.

The purpose of this study was to determine the effects of high-intensity endurance training on isokinetic muscle power. Six male students majoring in physical-education participated in high intensity endurance training on a cycle ergometer at 90% of maximal oxygen uptake (VO2max) for 7 weeks. The duration of the daily exercise session was set so that the energy expenditure equalled 42 kJ.kg-1 of lean body mass. Peak knee extension power was measured at six different speeds (30 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, and 300 degrees.s-1) with an isokinetic dynamometer. After training, VO2max increased significantly from mean values of 51.2 ml.kg-1.min-1, SD 6.5 to 56.3 ml.kg-1.min-1, SD 5.3 (P less than 0.05). Isokinetic peak power at the lower test speeds (30 degrees, 60 degrees and 120 degrees.s-1) increased significantly (P less than 0.05). However, no significant differences in muscle peak power were found at the faster velocities of 180 degrees, 240 degrees, and 300 degrees.s-1. The percentage improvement was dependent on the initial muscle peak power of each subject and the training stimulus (intensity of cycle ergometer exercise).

Adult↗
PubMed1989

Relative importance of aerobic and anaerobic energy release during short-lasting exhausting bicycle exercise.

Anaerobic energy release is of great importance for shortlasting exercise but has been difficult to quantify. In order to determine the amount of anaerobic energy release during shortlasting exercise we let 17 healthy young males exercise on the ergometer bike to exhaustion. The power during exercise was kept constant and selected to cause exhaustion in approximately 30 s, 1 min, or 2-3 min. The O2 uptake was measured continuously during the exercise, and the anaerobic energy release was quantified by the accumulated O2 deficit. The work done as well as the total energy release rose linearly with the exercise duration and was therefore a sum of a component proportional to time plus a constant addition. The accumulated O2 deficit increased from 1.86 +/- 0.07 (SE) mmol/kg for 30 s exercise to 2.25 +/- 0.06 mmol/kg for 1 min exercise and further to 2.42 +/- 0.08 mmol/kg for exercise lasting 2 min or more (P less than 0.01). The accumulated O2 uptake increased linearly with the duration, and as a consequence of this the relative importance of aerobic processes increased from 40% at 30 s duration to 50% at 1 min duration and further to 65% for exercise lasting 2 min. These results show that both aerobic and anaerobic processes contribute significantly during intense exercise lasting from 30 s to 3 min.

Adult↗
PubMed1988

Properties of component X of rat heart pyruvate dehydrogenase complex.

Pyruvate dehydrogenase complex was purified from rat heart. A new component(mol.wt; 52,000) was found in the purified complex in addition to well known three component enzymes. This component(referred to as component X) was acetylated with [2-14C] pyruvate in the absence of CoA as well as lipoate acetyltransferase. The anti-lipoate acetyltransferase antibody reacted with component X and lipoate acetyltransferase, suggesting that component X shows homology with lipoate acetyltransferase in protein structure. cDNA for lipoate acetyltransferase was isolated from rat liver cDNA library in lambda gt 11. cDNA for lipoate acetyltransferase recognized two kinds of mRNAs of 3.5 Kb and 2.5 Kb.

Acetyltransferases↗
PubMed1988

Anaerobic capacity determined by maximal accumulated O2 deficit.

We present a method for quantifying the anaerobic capacity based on determination of the maximal accumulated O2 deficit. The accumulated O2 deficit was determined for 11 subjects during 5 exhausting bouts of treadmill running lasting from 15 s to greater than 4 min. The accumulated O2 deficit increased with the duration for exhausting bouts lasting up to 2 min, but a leveling off was found for bouts lasting 2 min or more. Between-subject variation in the maximal accumulated O2 deficit ranged from 52 to 90 ml/kg. During exhausting exercise while subjects inspired air with reduced O2 content (O2 fraction = 13.5%), the maximal O2 uptake was 22% lower, whereas the accumulated O2 deficit remained unchanged. The precision of the method is 3 ml/kg. The method is based on estimation of the O2 demand by extrapolating the linear relationship between treadmill speed and O2 uptake at submaximal intensities. The slopes, which reflect running economy, varied by 16% between subjects, and the relationships had to be determined individually. This can be done either by measuring the O2 uptake at a minimum of 10 different submaximal intensities or by two measurements close to the maximal O2 uptake and by making use of a common Y-intercept of 5 ml.kg-1.min-1. By using these individual relationships the maximal accumulated O2 deficit, which appears to be a direct quantitative expression of the anaerobic capacity, can be calculated after measuring the O2 uptake during one exhausting bout of exercise lasting 2-3 min.

Adenosine Triphosphate↗
PubMed1988

Carcinoma of the ampulla of Vater: expression of cancer-associated antigens inversely correlated with prognosis.

To obtain some useful pathologic indicators for predicting the prognosis in carcinomas of the ampulla of Vater, we analyzed 24 surgically resected ampullary carcinomas pathologically with immunohistochemistry of cancer-associated antigens. Pancreatic invasion, lymph node metastasis, and histology of the tumor were significantly correlated with poor prognosis (p less than 0.01), but the size or ulceration of the tumor did not significantly affect the prognosis (p less than 0.05). Immunohistochemically, diffuse positivity for anti-CA19-9 monoclonal antibody was demonstrated in 10 carcinomas and that for anti-carcinoembryonic antigen (CEA), in 10. Eight of them showed synchronously diffuse immunoreactivities for both antigens. Although there was no significant correlation between diffuse positivity for CA19-9 and pathologic factors, CA19-9-positive cases exhibited significantly poor prognoses (p less than 0.01). Diffuse positivity for CEA was correlated with pancreatic invasion (p less than 0.05) and poor prognosis (p less than 0.05). Immunohistochemical study of cancer-associated antigens may disclose some malignant potential of ampullary carcinoma other than that expressed in the morphology. Furthermore, because of the consistency of staining results, immunohistochemistry of cancer-associated antigens may also be useful in predicting preoperatively the prognosis of ampullary carcinoma in biopsied materials.

Actuarial Analysis↗
PubMed1988

[A case of non-jaundice ampullary carcinoma with prominent lymphatic infiltration].

A case of a non-jaundiced ampullary carcinoma with a unique tumor spread is reported. A 3.2 X 1.0 cm-sized tumor at the ampulla of Vater was resected in a 64-year-old female. The primary focus of the well differentiated adenocarcinoma was confined to the intraampullary common channel, but the most of the tumor consisted of lymphatic permeation. A wide spread lymphogenous metastases had been noticed at operation, and the patient died nine months thereafter from metastases of the brain. The mechanism which prevented jaundice from developing in this case might be due to the unique way in which this tumor spread, without obstruction via the lymphatic space and only stenosing the bile duct.

Adenocarcinoma↗
PubMed1987

So-called "papillary and cystic neoplasm of the pancreas." An immunohistochemical and ultrastructural study.

A case of so-called "papillary and cystic neoplasm of the pancreas" (PCNP) was reported and investigated immunohistochemically and ultrastructurally. A tumor of the pancreatic head in a 21-year-old female was curatively resected. The tumor was cystic and histologically consisted of uniform cells in papillary and solid structure. Although there was no immunoreactivity for pancreaticogut hormones or secretory products of the pancreas in the tumor cells, most of the tumor cells were diffusely immunoreactive for neuron-specific enolase (NSE). Some neurosecretory granules were detected in the tumor cells ultrastructurally. Both facts suggested endocrine cell character of the tumor. Certain cases of PCNP might show a differentiation to endocrine cells.

Adult↗
PubMed1987

[Considerations on intraoperative radiation therapy and therapeutic ratio].

In conjunction with the clinical development of intraoperative radiation therapy (IORT), the ability to demonstrate an improvement in therapeutic ratio is critical and an evaluation of treatment complications is essential. The tolerance dose of the normal tissue in IORT is discussed, and if small field is applied, the greater part of tissues or organs tolerate intraoperative irradiations up to 25 Gy. The optimal dose has been estimated on each organs with malignant tumors. Intraoperative "boost" dose electron therapy given in combination with external beam irradiation has been demonstrated as good treatment modalities concerning with therapeutic ratio.

Brain Neoplasms↗
PubMed1987

A case of malignant cystic endocrine tumor of the pancreas.

A malignant pancreatic endocrine tumor with a cystic appearance in a 66-yr-old woman was reported. Total pancreatectomy was performed under the diagnosis of cystadenocarcinoma. The tumor was large and cystic, but the solid portion of the tumor showed histologically a ribbon-like array of small uniform cells typical for endocrine tumors. Immunohistochemically, most tumor cells were immunoreactive for neuron-specific enolase, chromogranin, and Leu 7-epitope. Ultrastructurally, innumerable neurosecretory granules were demonstrated in the cytoplasm of most tumor cells. The patient survived for 5.5 yr after operation despite liver metastases, some of which also showed cystic appearances.

Aged↗
PubMed1986

Activities of cefoxitin in vitro and in vivo: a study in patients with biliary tract infection undergoing percutaneous transhepatic biliary drainage.

Activities of cefoxitin and the effect on killing of bacteria in bile from six patients undergoing percutaneous transhepatic biliary drainage were analyzed in relation to in vitro activities of the drug, with particular reference to the incubation time. The bacteriostatic and bactericidal activities of cefoxitin with short term (6 hr) incubation correlated well with the duration of the effective cefoxitin concentration and the decrease of viable bacteria in bile juice from the patients. These timed in vitro activities can be used as well as the conventional MIC and MBC with the prolonged incubation of 24 hr, in the deductive analysis of bacterial response in vivo.

Aged↗
PubMed1985

Multiple paraganglioneuromas.

We report multiple paraganglioneuromas which occurred in a 40-year-old-man. Thirty-two tumours with similar histological appearance have been reported previously and most of them showed a striking predilection to occur in the second portion of the duodenum. In this case, three masses were detected; one was located in the periampullary region of duodenum with a polypoid appearance, the others were well defined masses in peri-pancreatic tissue adjacent to large vessels. Histology revealed two cellular components, epithelioid cells with NSE immunoreactivity and S-100 protein containing spindle-shaped cells. Moreover, on electron microscopical examination, three different epithelioid cell types were seen. Type I was a figure differentiating to ganglion cells, type II to paraganglion cells, type III was a hybrid form of ganglion and paraganglion cells. Paraganglioneuroma revealed the histopathology of ganglioneuroma, paraganglioma and also a mixed appearance. In this respect the tumour may be considered to originate in undifferentiated neural crest cells and develop organoid differentiation.

Adult↗
PubMed1984

Blood glucose concentration dependent ACTH and cortisol responses to prolonged exercise.

The purpose of this study is to investigate responses of serum ACTH and cortisol concentration to low intensity prolonged exercise. In experiment 1, 10 subjects fasted for 12 h and performed bicycle exercise at 49.3% VO2max (+/- 4.3%) until exhaustion or up to 3 h. During the early part of the exercise, serum ACTH and cortisol concentrations did not increase from the pre-exercise values (ACTH: 44 +/- 5 micrograms/l, cortisol: 139 +/- 52 micrograms/l). Whilst the time to serum ACTH concentration increasing varied among the subjects (60-180 min), the increases of this hormone occurred for all subjects (175 +/- 85 ng/l, P less than 0.05) when blood glucose concentration decreased to a critical level of 3.3 mmol/l. At the end of the exercise, blood glucose concentration decreased to 2.60 +/- 0.21 mmol/l, and serum ACTH and cortisol concentrations increased to 313 +/- 159 ng/l and 371 +/- 151 micrograms/l, respectively. In experiment 2, four subjects performed the same intensity exercise until exhaustion, and were then given 600 ml of 20 g glucose solution, and immediately afterwards, they were asked to repeat the same exercise. The subjects continued the exercise for between 30 to 90 min until again reaching exhaustion. During the second exercise, blood glucose concentration increased to the pre-exercise value (2.72 +/- 0.58 to 4.00 +/- 0.22 mmol/l, P less than 0.05) and simultaneously, serum ACTH concentration decreased considerably (354 +/- 22 to 119 +/- 54 ng/l, P less than 0.05). The results of the present study suggest that serum ACTH and cortisol concentration during low intensity prolonged exercise may be dependent on blood glucose concentration.

Adrenocorticotropic Hormone↗