PubMed Health⌕ Search

Biomedical subjects

M Ohtake

Publications and source records attributed to M Ohtake.

At least 55 records · Page 3Linked to original sources

Relative growth of leg segments of the German cockroach, Blattella germanica.

Measurements were made on the lengths of all the nine leg segments--coxa, trochanter, femur, tibia, and five tarsomeres--for three pairs of legs of both sexes throughout postembryonic stages. "Growth contours" were constructed to outline the temporal and spatial patterns of growth. Growth center was located in or near the 1st tarsomere of all the three pairs of legs, whereas growth depression was found in the 4th and 5th tarsomeres. Consequently, the relative length of the 1st tarsomere increased with the advance of the stage, while that of the 4th and 5th tarsomeres decreased. Ratios were calculated between the lengths of any dual combinations of the nine segments. Among these ratios, the tibia to femur ratio most distinctly changed with the kinds of legs. The 1st to the 5th tarsomere ratio most extensively increased with stage. Differences in relative length between the fore-, mid- and hindleg were examined for each of the nine segments. The differences were largest in the 1st tarsomere and tended to decrease toward the segments of both ends of the leg. The differences in coxa, trochanter, femur, and tibia tended to increase with stage, whereas those in five tarsomeres showed a decreasing tendency.

Animals↗

Inhibition of gastric motility induced by activation of the hypothalamic paraventricular nucleus.

Electrical stimulation of the paraventricular nucleus depressed the intragastric pressure of adrenalectomized male rats of which gastric movement had been induced by insulin-hypoglycemia. Electrical stimulation to the pituitary stalk produced a similar response in the pressure, but the response was abolished by bilateral lesion of the paraventricular nucleus. These findings allow us to speculate that the paraventricular nucleus is capable of modulating gastric motility, and suggest that the nucleus has a neural connection between the neurohypophysis and the system relevant to visceral function.

Animals↗

D-glucose anomers in the nucleus of the vagus nerve can depress gastric motility of rats.

The infusion of alpha-,beta-, or equilibrated (alpha: 36%; beta: 64%) D-glucose solution in the vicinity of the nucleus of the vagus nerve decreased gastric motility caused by insulin in rats with bilateral adrenalectomy. This effect was not reproduced after vagotomy at the cervical level. Of the 3 forms of D-glucose solution the effect of beta-D-glucose was greatest. The infusion of isotonic NaCl, however, produced no change in the motility. These results suggest that blood beta-D-glucose may predominantly activate a brain mechanism which vagally controls gastric motility at the medullary level.

Animals↗

Iron, zinc, copper, and manganese in infant formulas.

The concentrations of the trace elements iron, zinc, copper, and manganese were determined in 53 regular infant formulas and 41 special infant formulas used for clinical disorders. Several infant formulas had lower concentrations of trace elements than human milk. The ranges of concentrations found in the formulas were as follows: Iron, 0.0 to 57.5 mg/L; copper, 0.01 to 2.14 mg/L; zinc, 0.10 to 13.5 mg/L; and manganese, 0.0 to 7.8 mg/L. In addition to the wide variation in absolute amounts of the trace elements in the formulas, large variations in the ratios of trace elements were found. While the average ratios of zinc/copper, zinc/iron, and iron/manganese in human milk range from 3.3 to 10, 2.5 to 10, and 25 to 100, respectively, they ranged from 0.4 to 74, 0.02 to 40, and 0.04 to 425 in the formulas. These differences in the ratios may be important, as the ratio can affect the absorption of the individual elements. These findings indicate that more attention should be given to the trace element levels in infant formulas.

Copper↗

Salivary gland weight and nerve growth factor in the genetically obese (ob/ob) mouse.

The salivary glands of genetically obese male mice are significantly smaller than those of lean male mice, but the salivary glands of female mice do not differ in weight. The increases in weight of salivary glands in male mice after treatment with T3 at 50, 150, or 500 ng/day or with several doses of isoproterenol were comparable on a percentage basis, but the weights in the ob/ob mice were always smaller than any of those in the lean mice. Measurements of nerve growth factor (NGF) in several tissues showed a significantly lower concentration in the salivary glands of obese female mice than in same tissue from female lean mice. There were no differences in NGF levels in brown fat or in the cortex, cerebellum, or brain stem. The concentration of epidermal growth factor, in contrast to that of NGF, was not lower in the salivary glands of obese mice. Testosterone increased the weight of the salivary glands, spleen, and kidney in obese female mice, but the weight of the salivary glands in lean animals remained significantly higher than that in the obese mice both with and without treatment. Testosterone significantly increased the NGF concentration in salivary glands, but the values in treated male mice were only one tenth those in the treated lean animals.

Animals↗

Lymphoblasts and diagnosis of pyruvate carboxylase deficiency.

Pyruvate carboxylase activity was measured in phytohemagglutinin-transformed lymphocytes (i.e. lymphoblasts). Mean value +/- S.D. for 10 controls was 259 +/- 38 pmoles/min per mg protein. It was about 7 times higher than that of peripheral leukocytes and a half of cultured skin fibroblasts with similar techniques. Deficient pyruvate carboxylase activity less than 6 pmoles/min per mg protein was demonstrated in the lymphoblasts from a patient with biotin-dependent multiple carboxylase deficiency. It is suggested that lymphoblasts may allow more reliable and ready diagnosis of patients with pyruvate carboxylase deficiency.

Adult↗

Pyruvate decarboxylase deficiency in a patient with Leigh's encephalomyelopathy.

A 23-month-old boy with progressive muscular hypotonia and mental and motor deterioration was described. Four days after the admission he had a respiratory arrest and required the care in a respirator thereafter. Laboratory examinations showed metabolic acidosis and high levels of pyruvate, lactate and alanine in blood and cerebrospinal fluid. Oral administration of thiamine-HCl and lipoic acid was noneffective and he died 7 months after the admission. Autopsy findings were compatible with subacute necrotizing encephalomyelopathy (Leigh's disease). The activity of pyruvate decarboxylase in autopsy samples was not detectable and that in fibroblasts was 9% of that in control cell lines. The present study confirmed that pyruvate decarboxylase deficiency is one of the causes of Leigh's disease.

Brain↗

Zinc and copper concentrations in human milk and in serum from exclusively-breast-fed infants during the first 3 months of life.

Zinc and copper concentrations in human milk and in serum from exclusively-breast-fed infants born at full-term were serially determined during the first 3 months of life by the atomic absorption spectrophotometric method. Zinc and copper concentrations of human milk decreased as the stage of lactation progressed. The mean value of the concentration of serum zinc at birth was just below the value previously reported for school children, significantly decreased at one month of age (p less than 0.02), then returned to the level at birth at 2 months of age, and reached at 3 months of age to the level of school children. On the other hand, the mean value of serum copper at birth was markedly low, and rapidly increased until 2 months of age and then gradually increased until 3 months of age. These changes in serum zinc and copper concentrations during early infancy suggested that human milk can provide sufficient zinc and copper for full-term infants during the first 3 months of life. Calculated daily zinc and copper intakes in infants fed on human milk were lower than recommended values. It is necessary to reconsider the appropriateness of previously recommended values for breast-fed animals.

Adult↗

Chronic hypernatremia associated with holoprosencephaly.

Two patients ( 1 7/12-year-old and 1 11/12-year-old girls) with chronic hypernatremia were studied. Neuroradiological findings and mildine facial defects showed characteristic features of holoprosencephaly. Water deprivation tests showed clear evidence of antidiuretic hormone (ADH) secretion. The responses to hypertonic saline infusion and acute water loading were abnormal. In one case, the impaired osmotic regulation of ADH secretion was demonstrated by measuring urinary ADH by a radioimmunoassay. In this case, the volume regulation of ADH secretion seemed to be also incomplete since chronic water loading for a period of six days induced water retension.

Brain↗

Effects of ether and pentobarbital anesthesia on thyroid function in the rat.

Studies were performed to examine the effect of two anesthetic agents, ether and pentobarbital, on the hypothalamic-pituitary-thyroid function in vivo. In non-anesthetized animals, plasma thyrotropin (TSH) increased rapidly from basal values of 0.1, a peak of 0.49 microng/ml, 25 min after exposure to the cold. Anesthesia with ether during exposure to the cold completely prevented the rise in TSH. During pentobarbital anesthesia, the rise in TSH after exposure to cold was reduced by more than 90%. Even a three minute period of ether anesthesia prior to cold exposure reduced the peak response to cold as well as delayed this response when compared to the untreated group. During two hours of anesthesia with ether, the TSH concentration declined in animals which were fed a low iodine diet at essentially the same rate as in animals on the same diet given an injection of 3 microng of triiodothyronine. Pentobarbital did not suppress TSH at room temperature. The release of thyrotropin after injection of synthetic thyrotropin-releasing hormone (TRH) was greater in animals anesthetized with pentobarbital than in controls and was slightly reduced in ether-anesthetized animals. This difference was observed when thyrotropin was given intraperitoneally or intravenously and the slope of the dose-response curves to TRH showed a flattening of the curve of rats treated with ether and a steeper slope of response in animals anesthetized with pentobarbital. We conclude that pentobarbital inhibited TSH response to cold but did not reduce the resting levels. Ether inhibited the rise of TSH in the cold and lowered the basal levels of TSH in animlas at room temperature. Pentobarbital increased the response to TRH and ether may have reduced the response to TRH.

Animals↗

A device for expressing the serum insulin glucose relationship in diabetes, hyper- or hypothyroidsm, and chronic hepatitis.

When the serum insulin valves during a 50-gm oral glucose tolerance test were expressed as the function of glucose concentrations, a good linear relationship was found in normal subjects and in patients with diabetes, hyperthroidism, hypothroidism or chronic hepatitis. The insulin index calculated from the line representing this relationship was less than 100 in all 19 diabetic patients and most of the 13 hyperthyroid patients with oxyhyperglycemia, whereas it was more than 100 in the 14 normal subjects, the 4 hypothyroid patients, and the 8 patients with oxyhyperglycemia due to chronic hepatitis. The insulin index decreased with increasing maximal blood glucose concentration during the glucose tolerance test in diabetic patients. Furthermore, improvement in the insulin index was correlated with the effectiveness of sulfornylurea drugs in the diabetic group.

Adult↗