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T Rikimaru

Publications and source records attributed to T Rikimaru.

85 records · Page 5Linked to original sources
PubMed1983

Contributions of individual body tissues to nitrogen excretion in adult rats fed protein-deficient diets.

An attempt was made to estimate the contributions of various tissues to nitrogen (N) excretion in rats fed protein-free diet or 2 and 10% lactalbumin diets for 14 to 31 days. The contributions were calculated as differences between the amounts of dietary N utilized for tissue protein and tissue growth. The amount of dietary N utilized for tissue protein was calculated from the recovery of 15N of orally administered [15N]leucine and N intake. The following results were obtained. 1) With a 10% protein diet, the contribution of tissues to N excretion was affected more by the turnover rates of individual tissues than by the size of the tissues, but with a protein-free diet the contribution was greatly affected by the size of the tissues. 2) With 2% lactalbumin diet, the contributions were not intermediate between those with protein-free diet and 10% lactalbumin diet: urinary N excretion was similar to that with protein-free diet in spite of the difference in N intake, probably mainly because the contribution of skeletal muscle was lower. 3) Differences in the dietary protein level affected the utilization of dietary protein only a little, but influenced body protein metabolism very much.

Animals↗
PubMed1982

Studies on protein nutrition of Papua New Guinea highlanders: nitrogen balance and hematological studies.

Studies were made in August 1978 on the N-balance and hematological characteristics of 18 men living in the village of Kalugaluvi (altitude: 1,500m) near Lufa, which is 60km from Goroka, in the Eastern Highland Province of Papua New Guinea. The average daily protein intake on 3 consecutive days was 95.2 +/- 29.3 mgN/kg (35.2 +/- 10.7 g protein/day), and 32.6 +/- 18.7% of the total protein intake was in the form of animal proteins. The calculated nutritional value of the dietary protein, scored according to the 1973 FAO/WHO pattern, was 83.7 +/- 10.6. Urinary and fecal N excretions during the same period were 81.9 +/- 18.7 and 26.3 +/- 11.8 mgN/kg, respectively, giving a nitrogen balance of -13.5 +/- 24.9 mgN/kg. From N-balance data on individuals, the N-intake for maintenance of a zero N-balance was estimated as 116.3 +/- 48.6 mgN/kg (mean 95% confidence interval). Hematological data showed normal or rather high values for hemoglobin (16.90 +/- 1.05 g/100 ml) and serum proteins (8.05 +/- 0.40 g/100 ml). The increased level of serum proteins was associated with an increased globulin level.

Adult↗
PubMed1981

Effects of dietary protein or amino acids in the perfusion medium on amino acid metabolism in perfused adult rat liver.

To elucidate the response of amino acid metabolism in the liver to dietary protein and plasma amino acids, the livers of adult rats fed on diet containing 10% (control) or 3% (low-protein) egg protein for 3 weeks were perfused for 120 min with amino acid-free medium in Experiment 1 or medium containing an amino acid mixture simulating that in plasma in Experiment 2. During perfusion about 40% of the free amino acids were lost from the liver in Exp. 1, and about 30% in Exp. 2. During this period, in Exp. 1 the releases of free amino acids and urea into the medium were 140 mumol and 2.52 mg, respectively, in the control group and 207 mumol and 1.10 mg respectively, in the low-protein group. Thus release was greater than decrease in free amino acids in the liver. Essential amino acids, particularly lysine and branched chain amino acids, were released preferentially. The results suggest that the amount of breakdown of liver protein in the two groups was similar, but that the nitrogen was mainly released as free amino acids in the low-protein group, and as urea in the control group. On the contrary, in Exp. 2 the amount of nitrogen released from the liver was comparable to the decrease in amino acids in the liver, and the releases of urea were also less, being 1.83 mg in the control group and 0.54 mg in low-protein group. The results show that amino acid metabolism in the liver is greatly affected by the nutritional state of the animal and the amino acid content of the perfusion fluid.

Amino Acids↗
PubMed1981

Nutritional status of Papua New Guinea highlanders.

A nutritional survey was held in August, 1978, at Kalugaluvi (altitude: 1,500m) near Lufa, which is 60 km from Goroka, in the Eastern Highland Province of Papua New Guinea. Anthropometric measurements were carried out on 55 males and 37 females aged from 7 to 64 years. whereas the physiques of the children looked as good as those of Japanese of a comparable age, the adult men were shorter than Japanese males, but body weight and chest girth were similar. The skinfold thickness was less than that of the Japanese. From the data collected, it was shown that the physique of the Highlanders was more muscular than that of the Japanese. The food intakes and energy balances of 18 healthy men (20-40 years old) were measured over 2 or 3 consecutive days. The average consumption of sweet potatoes, the staple food, was 956 +/- 305 g per day. The average consumption of taro and yam was 93 +/- 124 g/day and 36 +/- 99 g/day, respectively. Various green leaves, sugar canes, corn, bananas and other foods. (i.e., rice and tinned fish) purchased from trade stores were sometimes eaten. The mean daily energy intake was 2.390 +/- 540 kcal, which was about the same as the daily energy expenditure. The daily protein intake was 35.2 +/- 10.7 g. These results are probably exceptionally high, because the survey was unfortunately held during the yearly festival season of the village when the people often ate fatty port. Nevertheless, it is noteworthy that the growth of children and the physique of adults are normal in spite of the extremely low intake of protein.

Adolescent↗
PubMed1980

Effects of protein deficiency on muscle myofibrillar protein turnover in adult rats.

The rates of gain, catabolism, synthesis and reutilization of myofibrillar protein were measured in adult rats fed a protein-free diet, low protein diet (2% lactalbumin) or control diet (10% lactalbumin) for 14 to 31 days. Two forms of synthesis were measured: exogenous synthesis (nitrogen derived from diet) and endogenous synthesis (nitrogen derived from catabolized body protein). The rate of gain of myofibrillar protein was measured as the rate of increase in its weight and the rate of catabolism was determined from urinary 3-methylhistidine excretion. The rate of total synthesis was calculated as the sum of these two rates. Exogenous synthesis was calculated from the recovery of isotope in protein 24 h after oral administration of 15N-leucine and endogenous synthesis was calculated as the difference between the total synthesis and exogenous synthesis. Reutilization was calculated as the ratio of endogeneous synthesis to catabolism. The rate of catabolism was slightly decreased in protein deficiency (2.1, 2.1 and 2.6% in the protein-free, low protein and control groups, respectively), while that of synthesis was significantly decreased in protein deficiency (1.3, 2.0 and 3.3% in the respective groups). Restriction of protein intake resulted in a decrease in the rate of exogenous synthesis, without appreciable change of endogenous synthesis. The reutilization rate of endogenous N was estimated to be about 70% in rats with restricted protein intakes and about 50% in those with a normal protein intake.

Animals↗
PubMed1979

Effect of low protein diets on free amino acids in plasma of young men: effect of wheat gluten diet.

Studies were made on alterations in plasma amino acids in young men fed a diet containing graded levels of wheat gluten. After one week on a standard diet containing 200 mgN/kg of mixed protein (animal protein content 45%), 38 young men were given a wheat gluten diet containing 170, 100, 60, 30, 15 or zero mgN/kg for 2 weeks. Blood samples measuring plasma free amino acids were taken before breakfast at the end of the periods on a standard diet and an experimental diet. In subjects on diets containing 170 to 30 mgN/kg the plasma concentrations of threonine, valine, methionine, leucine, tyrosine, phenylalanine, serine, histidine and arginine fell significantly with decrease in protein intake, but the concentration of alanine increased significantly. On the other hand, in subjects on diets containing 15 or zero mgN/kg, the plasma concentrations of the essential amino acids did not decrease, but increased to slightly more than in subjects on a diet containing 30 mgN/kg, and the alanine and glycine concentrations increased steadily. Values for plasma lysine varied from 146 +/- 22 to 194 +/- 31 mumoles/liter with gluten intakes of 170 to zero mgN/kg, but were comparable with that of 186 +/- 33 mumules/liter in subjects on a standard diet, showing that the plasma lysine concentration did not clearly reflect the dietary concentration of lysine in young men on a wheat gluten diet.

Adult↗
PubMedDate not supplied

Decreased cysteine and glutathione levels: possible determinants of liver toxicity risk in Ghanaian subjects.

Cysteine, methionine, vitamin A, beta-carotene and glutathione (GSH) are known to protect body tissues against oxidative damage and inflammation but their value as protection against liver inflammation in tropical areas has received little attention. Blood levels of these nutrients were measured in Ghanaian volunteers with (Group 2) or without (Group 1) increased lipid peroxidation and signs of liver inflammation, as indicated by blood malonic dialdehyde, serum alpha 1-antitrypsin and triglyceride levels, and the alpha 1-acid glycoprotein:pre-albumin ratio. Serum levels of cysteine and blood glutathione were significantly lower (P < 0.02) in group 2 than in group 1 volunteers. In contrast, serum levels of methionine, vitamin A and beta-carotene were similar in both groups. Deficits in cysteine and glutathione may increase the risk of liver toxicity from oxidants in Ghanaians.

Adult↗
PubMedDate not supplied

Characteristics of sarcomatous cholangiocarcinoma of the liver.

BACKGROUND/AIMS: The aim of this study was to clarify the clinicopathological characteristics of intrahepatic cholangiocarcinoma with sarcomatous changes. METHODOLOGY: Four cases of cholangiocarcinoma with sarcomatous change were identified and investigated. The clinicopathological findings, including the results of immunohistochemical staining, were investigated in comparison with those of ordinary cholangiocarcinoma. RESULTS: Two of them exhibited pyrexia as the initial symptom. The serum alkaline phosphatase level in sarcomatous cholangiocarcinoma was significantly lower than that in ordinary cholangiocarcinoma. Both the serum carcinoembryonic antigen and carbohydrate 19-9 level in sarcomatous cholangiocarcinoma also tended to be lower than those in ordinary cholangiocarcinoma. The carcinomatous component of all tumors was mostly poorly differentiated adenocarcinoma. The associated microscopic findings were as follows: lymphocyte infiltration in the tumor, accompanied by both necrosis and extensive lymph node metastases. Three of them predominantly exhibited spindle-shaped sarcomatous changes, whereas the other case predominantly demonstrated pleomorphic-type sarcomatous changes. The sarcomatous area was positive for both vimentin, a mesenchymal marker, and for epithelial markers, furthermore, in 3 of 4 cases, the carcinoma portions were also positive for vimentin. The overall survival curves were not significantly different between the 2 groups, however, no long-term survivor was found in sarcomatous cholangiocarcinoma. CONCLUSIONS: The main characteristics of cholangiocarcinoma with sarcomatous changes are considered to be as follows: 1) often demonstrating pyrexia as a symptom; 2) not always demonstrating remarkable abnormal findings in the laboratory data including tumor markers; 3) histologically showing poorly differentiated adenocarcinoma; and 4) showing a very poor prognosis (especially, in a pleomorphic-type).

Aged↗
PubMedDate not supplied

Surgical indications for advanced hepatocellular carcinoma.

BACKGROUND/AIMS: The aim of this study is to clarify the limitations of hepatectomy for advanced hepatocellular carcinoma. METHODOLOGY: Fifty-six patients with Stage 4 hepatocellular carcinoma were retrospectively studied, and the prognostic factors were both univariately and multivariately analyzed. The VI score, which was defined as the degree of portal vein invasion (VP) multiplied by the degree of intrahepatic metastases (IM), was introduced as a new prognostic indicator. RESULTS: A univariate analysis revealed the following significant variables: hypertension, esophageal varices, Child's classification B or C, a bilirubin value of over 1.0 mg/dL, a albumin value of below 3.5 g/dL, a GOT value of over 100 IU/L, an AFP value of over 1000 ng/mL, a history of tumor rupture, Stage 4B, a tumor size of over 5 cm, VP3, IM3, and the VI score of no less than 6. A multivariate analysis demonstrated the following 4 variables to be independent prognostic indicators: a Stage of 4B, a VI score of no less than 6, a Child's classification of B or C, and a tumor size of over 5 cm. Furthermore, no long-term survivors were found in patients with either Stage 4B HCC or a hepatocellular carcinoma having a VI score of more than 6. At the present time, either Stage 4B or a hepatocellular carcinoma having a VI score > or = 6 are considered to be factors which means the limitation of hepatectomy alone. Furthermore, an advanced hepatocellular carcinoma with either poor liver function or a hepatocellular carcinoma with a size of over 5 cm should be carefully evaluated before determining its appropriateness for hepatectomy. CONCLUSIONS: The VI score is therefore suggested to be a useful prognostic indicator for determining the surgical indications for advanced hepatocellular carcinomas.

Adult↗
PubMedDate not supplied

Thrombectomy before hepatic resection for hepatocellular carcinoma with a tumor thrombus extending to the inferior vena cava.

Tumor thrombi of hepatocellular carcinoma occasionally invade into the inferior vena cava (IVC) through the hepatic vein. Once the tumor thrombus is dislodged, severe and lethal complications, such as pulmonary infarction, can develop. We successfully operated on a hepatocellular carcinoma (HCC) patient with a tumor thrombus extending to the IVC through the right hepatic vein. To avoid dislodging the thrombus during surgery, a thrombectomy using selective hepatic vascular exclusion was performed before a hepatic resection, which is the most dangerous procedure to dislodge the thrombus.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Vitamin A status and nutrient intake in a rural community in southern Ghana.

The present study was designed to assess the vitamin A status in a rural community (Gomoa Onyadze) in southern Ghana, to determine if there is any vitamin A deficiency in the community and also to estimate the nutrient intake of the inhabitants to see if the levels conform to the Recommended Dietary Allowance (RDA). Results of serum vitamin A analysis indicated that out of total of 263 subjects (3-60 years) screened, 0.76% had deficient vitamin A level of < 10 micrograms/1); 11.79% had low levels of 10-20 micrograms/dl; 83.65% had adequate levels of 20-50 micrograms/dl, while 3.80% had high levels (> 50 micrograms/dl). Since the deficient group (i.e. < 10 micrograms/dl) was less than 5% of total subjects screened, it is concluded that there is no vitamin A deficiency in the community. Dietary intake measurements showed that nutrient intake in subjects with normal or abnormal levels of vitamin A are similar and are, with some exceptions (energy, vitamin-thiamine, riboflavin and niacin), acceptable when compared with the RDA.

Adolescent↗