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Biomedical subjects

Y Morikawa

Publications and source records attributed to Y Morikawa.

At least 343 records · Page 19Linked to original sources
PubMed1979

Manometry and histochemistry in the diagnosis of Hirschsprung's disease.

Acetylcholine esterase histochemistry and rectal manometry have been used sequentially to evaluate constipated children and to make the diagnosis of Hirschsprung's disease. When applied together, these modalities give a reliable diagnosis of Hirschsprung's disease, restricting the use of deep rectal biopsy to those patients in whom symptoms are most suggestive of Hirschsprung's disease. Acetylcholine esterase histochemistry may be more reliable than rectal manometry in the newborn and premature periods. It is hoped that the combined use of these techniques may make deep rectal biopsy obsolete except in patients with hypoganglionosis.

Acetylcholinesterase↗
PubMed1978

NAD recycling in the collagen membrane.

NAD recycling in the collagen membrane was investigated as follows: (1) Alcohol dehydrogenase and lactate dehydrogenase were co-immobilized in the collagen membrane and the rate of lactate production by immobilized enzymes was compared with that of free enzymes by using free NAD. An increased rate was observed in the case of immobilized enzyme. (2) The soluble high molecular weight derivatives of NAD (dextran-NAD) were immobilized in the collagen membrane with the two dehydrogenases and recycling of dextran-NAD in the membrane was examined. Lactate was produced by the membrane without adding free NAD. The interaction between the high molecular weight NAD derivatives and enzymes are also discussed.

Alcohol Oxidoreductases↗
PubMed1978

Changes in placental permeability to corticosterone and estradiol-17beta toward the end of gestation in the rat.

Radioactivity in the fetal plasma 1 h after maternal injection of 14C-4-corticosterone or 14C-4-estradiol-17 beta on day 21 of gestation was markedly higher than that 1 h after injection on day 22. Radioactivity in the maternal plasma was not different on these 2 days. The results suggest that the placental permeability to steroids from the mother to the fetus declines toward the end of gestation in the rat.

Animals↗
PubMed1978

Development of the fetal pituitary-testicular system based on the observation of Leydig cells in encephalectomized, hypophysectomized and control fetal rats.

The time of onset of brain regulation of the pituitary-Leydig cell system in fetal rats was assessed by fetal encephalectomy, which allowed the pituitary to persist in situ. The effects of encephalectomy were compared with those of fetal hypophysectomy (surgical decapitation). The parameter for interpretation of these effects was the collective volume of Leydig cells, measured by the method of Chalkley ('43). The normal increase in the collective volume of Leydig cells in fetuses encephalectomized on day 17 of gestation and autopsied on day 18 was not retarded, whereas that in decapitated fetuses of the same age was retarded. In all other one-day experimental periods (day 18-19, 19-20, 20-21, and 21-22), the increase in volume was retarded to approximately the same extent in encephalectomized as in decapitated fetuses. The collective volume of Leydig cells continued to increase to some extent without the brain until day 20, after which it ceased to increase. The results suggest that in fetal rats, the brain control of the pituitary-Leydig cell system begins to operate from day 18 of gestation, when the day following overnight mating was designated as day 1 of gestation.

Animals↗
PubMed1978

Cholinergic nerve development of fetal lung in vitro.

The development of the cholinergic or parasympathetic nervous system was studied in embryonic lung dissociated from the central nervous system and placed in organ culture. In vitro development was similar to that seen in vivo. This study demonstrated that migration of neuroblasts from the central nervous system to the trachea takes place before day 12. Neuroblasts differentiate to small immature ganglia and then to larger more mature ganglia that give off nerve fibers to the submucosa and the epithelium. This isolated lung preparation was used to study neurostimulators. Thyroxine (T4) was found to accelerate nerve fiber growth and differentiation of ganglia in vitro. The neuroepithelial body, an epithelial cell with acetylcholine-esterase-positive granules, also differentiated in vitro. This cell may fill the morphologic criteria of an intrapulmonary chemoreceptor.

Animals↗
PubMed1978

Studies on 15-hydroxyprostaglandin dehydrogenase with various prostaglandin analogues.

The NAD+-linked 15-hydroxyprostaglandin dehydrogenase (PGDH) of swine lung was purified to a high specific activity by affinity chromatographies on prostaglandin (PG)-and NAD+-Sepharose. The affinities of the enzyme for various synthetic analogues of PGA, E, F, and I and their inhibitory effects on the enzymatic reaction were examined. The modification of the alkyl side chain of PG, particularly at C-15 or C-16, reduced the affinity of the enzyme for these PG analogues. Furthermore, 14-methyl-13,14-dihydro-PGE1 and 16-cyclopentyl-omega-trinor-15-epi-PGE2 were potent inhibitors of PGDH.

Animals↗
PubMed1978

Increased secretion of Müllerian inhibiting substance after immunological blockade of endogenous luteinizing hormone releasing hormone in the rat.

In order to evaluate the role of leuteinizing hormone releasing hormone (LHRH) and gonadotropins in the control of secretion of Müllerian inhibiting substance, groups of pregnant rats were injected intraperitoneally with high potency antiserum from a rabbit immunized with LHRH. Pregnant females were injected at 13 and 20 days of gestation with LHRH antiserum or an equal volume of normal rabbit serum as a control. The testes and penis were reduced in weight and size in 6-day-old pups of the experimental group indicating the luteinizing hormone (LH) was blocked and that LHRH antiserum was active. Testicular fragments of 17-day fetuses and 6-day-old pups showed an increase relative to controls in Müllerian inhibiting substance activity in a graded organ culture bioassay system. These studies suggest that secretion of Müllerian inhibiting substances is curtailed by one or both gonadotropins.

Animals↗
PubMed1978

[Clinical evaluation of intravenous administration of ampicillin-oxacillin (Broadcillin 'Banyu') in bacterial infections in children (author's transl)].

Broadcillin 'Banyu', which contains an equal amount of ampicillin and oxacillin was given intravenously to children with acute bacterial infections and the following results were obtained. 1. Patients were 55 children with the following bacterial infections; respiratory tract infections (8 cases), pneumonia (34), sepsis (1), meningitis (1), cutaneous and subcutaneous suppurative inflammation (5), osteomyelitis (1), urinary tract infection (2), enteritis (1), and chemoprophylaxis (2). They ranged in age from newborns to 8 year old, but most of them were infants. In the majority of the patients, broadcillin 'Banyu' was administered 50 approximately 150 mg/day in three to four equally divided doses by one shot-injection or by a continuous drip infusion for a period of 2 approximately 10 days. The overall efficacy rate was 88.7% in 53 cases after two cases of chemoprophylaxis were excluded, i.e., excellent in 28, good in 19 and failure in 6: excellent in 4 and good in 4 in 8 cases of respiratory tract infections; excellent in 20, good in 11 and failure in 3 in 34 cases of pneumonia (an efficacy rate 91.2%); failure in sepsis and meningitis: excellent in 2 and good in 3 in 5 cases of cutaneous and subcutaneous suppurative inflammation; excellent in osteomyelitis; excellent in 1 and good in 1 of 2 cases of urinary tract infection; failure in enteritis. 2. Adverse reactions were noted on 10 occasions in 9 cases (16.4%), including 1 case of skin eruption, 1 case of eosinophilia, 5 cases of slight elevation of GOT, 1 case of slight elevation of GPT and 2 cases of slight elevation of BUN. 3. Based on the above results, it was concluded that clinical effect of broadcillin 'Banyu' by an intravenous administration is comparable to its intramuscular route and that safety of intravenous usage seems to be verified as long as the above described dosage is followed.

Acute Disease↗
PubMed1978

[Experimental studies on the passage of antibiotics into cerebrospinal fluid in staphylococcal meningitis in rabbits. II. Cephaloridine, cephalothin and cefazolin (author's transl)].

Passage of cephaloridine, cephalothin and cefazolin into cerebrospinal fluid (CSF) was evaluated in Staphylococcus aureus meningitis in rabbits and the following results were obtained. 1. Concentration in CSF (microgram/ml) [CSF/serum ratio (%)] was determined 1/2, 1 and 2 hours after a single intravenous injection of 100 mg/kg of each antibiotic, respectively; cephaloridine-7.5 [8.9], 9.7 [13.8], 9.1 [22.6]; cephalothin-0.42 [3.6], 0.23 [6.4], not detectable [0]; cefazolin-7.5 [11.8], 5.2 [19.3], 2.0 [17.5]. 2. When results with cefazolin after an intravenous injection 100 mg/kg and 200 mg/kg were compared, a definite dose response was noted in blood concentration but not in CSF concentration. 3. A standard error of CSF concentrations of each antibiotic was larger than that of penicillins, and "Unpredictability" of their passage into CSF was considered to be one of the characteristics common to these three drugs in respect of their passage into CSF. 4. There was no significant difference noted in antibiotic passage into CSF between cephaloridine of low protein binding rate and cefazolin of very high binding rate. Cephalothin, of which binding rate was intermediate, showed a remarkably lower passage into CSF. These results indicate that a correlation does not always exist between protein binding rate of the antibiotics and their passage into CSF. 5. Based on the above results, a review of the literature was made on clinical applicability of these three antibiotics in the treatment of bacterial meningitis. Low transport rate of cephalothin into CSF and nephrotoxicity of cephaloridine make them to be unsuitable for bacterial meningitis. Cefazolin is considered to be suitable in the treatment of ampicillin-resistant Escherichia coli meningitis and Gram-positive coccal meningitis in which penicillins are not applicable.

Animals↗
PubMed1977

Granularity of cells in the juxtaglomerular apparatus in fetal rats after maternal nephrectomy or fetal unilateral nephrectomy.

Granular cell indices (GCI: Dunihue and Robertson, '57) in kidneys of fetal rats one day after maternal nephrectomy of fetal unilateral nephrectomy on day 21 of gestation were determined by examining sections stained with Bowie's technique. Maternal nephrectomy induced an extreme increase of GCI in fetal kidneys with increased granularity of cells in the juxtaglomerular apparatus. Fetal unilateral nephrectomy did not cause any significant change.

Animals↗
PubMed1977

Mullerian inhibiting substance in human testes after birth.

Tiny testicular biopsies from humans were assayed for Mullerian inhibiting Substances using a graded organ culture technique. Mullerian Inhibiting Substance activity was high during the first year of life, declined during the second year of life, and then disappeared. Mullerian Inhibiting Substance activity is lower in boys with undescended testis than in children with normal or intersex testes at comparable ages under two years. It is possible that Mullerian Inhibiting Substance affects testicular descent as well as causing Mullerian duct regression.

Adolescent↗