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Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 721 records · Page 40Linked to original sources
PubMed1991

[3H]mepyramine binding sites, histamine H1-receptors, in bovine retinal blood vessels.

The presence of histamine H1-receptors in the bovine retinal blood vessels was studied with a [3H]mepyramine binding assay. The membranes of purified vessels obtained from bovine retinas showed specific [3H]mepyramine binding sites with a dissociation constant (KD) of 2.78 +/- 0.32 nM. This was similar to values obtained from the retinal neuronal fractions. The binding capacity (Bmax) was 53.8 +/- 1.7 fmol/mg protein, which was about a half that of the retinal neuronal fractions (108.9 +/- 3.1 fmol/mg protein). Some H1-antagonists proved to be potent competitors for [3H]mepyramine binding sites in bovine retinal blood vessels. These results indicate that histamine H1-receptors exist in the retinal blood vessels which may be involved in the physiological and the pathological responses of blood circulation in retinas.

Animals↗
PubMed1991

[Plasma thrombomodulin levels in elderly subjects].

Plasma levels of thrombomodulin (TM), fibrinogen, antithrombin III (ATIII) and thrombin ATIII complex (TAT) were studied in healthy young subjects (group A), healthy elderly subjects (group B) and patients with level of TM in group B tended to be higher than that in group A. Levels of TM, fibrinogen and TAT in group C suggested the presence of a hypercoagulable state. When group C was further divided into those with and without diabetes mellitus (DM), the TM level in the former tended to be higher than that in the latter. Furthermore, among the patients with DM, those with diabetic retinopathy showed significantly higher levels of TM than those without retinopathy. Thus, high TM levels indicate the presence of endothelial injury. In groups B and C, TM correlated positively with fibrinogen, and negatively with ATIII, which also indicates that a high TM level is related to a hypercoagulable state. In conclusion, the TM level is considered to be a potential marker of the presence of endothelial injury.

Adult↗
PubMed1991

Organ assimilation of peptides.

Dipeptides injected intravenously or added to liver perfusion medium were hydrolyzed rapidly to amino acids. The clearance volumes per min of plasma Gly-Phe and Gly-Lys were 63% and 224%, respectively, of the total plasma volume. These values far exceed the blood flow in any single organ, suggesting that several organs must be involved in peptide assimilation. Intravenous administration of peptides increased the levels of their constituent amino acids in organs. Two possible explanations for this were assimilation of the peptides by the organs, and transport into the organs of the amino acids generated by extracellular hydrolysis of the peptides. The former possibility was tested by eliminating plasma lysine by enzymic degradation, so that the amino acid would accumulate only in the organs that assimilate lysine-containing peptides. Results showed that all organs tested, except the brain, had an intrinsic ability to assimilate peptides.

Animals↗
PubMed1991

[Histamine metabolism in the nasal tissue of human and nasal hypersensitive guinea-pig].

Histamine (HA) is the most important mediator of nasal allergy and nasal hypersensitivity. To investigate HA metabolism, HA content and activities of its synthetic enzyme, histidine decarboxylase (HDC) and degrading enzymes, histamine-N-methyltransferase (HMT) and diamine oxidase (DAO) in nasal mucosa of human and toluene diisocyanate (TDI) sensitized guinea-pigs were measured. In human nasal mucosa and nasal polyps, HA content and HDC activity were 80-200 nmol/g tissue, 20-30 fmol/min/mg protein respectively. Among two degrading enzymes, HMT activity was 20-200 times higher than that of DAO. In the nasal mucosa of guinea-pigs, HA content was significantly increased by TDI sensitization, and was decreased immediately after TDI provocation. In 24 hours after provocation, HA content recovered to 80% of pre-provocation level. HDC activity increased by TDI sensitization significantly. Though HMT activity increased slightly by TDI sensitization and provocation, DAO activity was unchanged. The data suggest that, increase in turnover rate of HA is present in allergic nasal mucosa.

Amine Oxidase (Copper-Containing)↗
PubMed1991

[Clinical significance and usefulness of measuring nocturnal penile tumescence in children].

Nocturnal penile tumescence (NPT) is a physiological phenomena that is recognized in almost all normal males. This paper presents a study of NPT and the relation of this phenomenon to age, sexual maturation and physical growth in children. In 30 subjects, ranging from 3 to 18 years old, NPT was measured continuously throughout the night. The following results were obtained: 1. The frequency of NPT had a tendency to increase with age with a maximum frequency at 13 or 14 years of age, although the frequency ranged widely. 2. The maximum increase in penile circumference was below 10 mm in all cases below 10 years of age but was greater in children over 12 years old. 3. Tumescence time and percent tumescence time [tumescence time (min.)/sleep period time (min.)] x 100) was greater in children of over 12 years of age. Percent tumescence time showed a positive correlation with serum LH. Percent tumescence time was clearly higher in children with LH pulse, which indicates the onset of puberty, than in those without it. 4. These results suggest that NPT measurement in children can predict the onset of puberty, when coupled with endocrinological findings.

Adolescent↗
PubMed1991

[The role of surgeon in treatment of chronic respiratory failure after pulmonary tuberculosis operations].

We analyzed pulmonary functions and rib cage-phrenic motions on 296 cases of chronic empyema patients who had surgical treatment. Pulmonary functions were better preserved in patients with a single step than in those with multi-step operations, and in those who had more than five operations the impairment was inevitable. Both %VC and rib cage-phrenic motions improved by decortication, and by air-plombage, but in those who developed multi-rib fractures after the latter procedure, ipsilateral chest wall motion almost disappeared. Since some restriction of rib cage-phrenic motion is inevitable after the surgery, we have developed a cuirass respirator which can synchronize with the respiration to assist the movement of the chest wall. The results attained so far are satisfactory.

Aged↗
PubMed1991

Histamine and its synthesis in mammalian retinas.

Histamine (HA) content and histidine decarboxylase (HDC) activity were studied in the sensory retinas of the rat, guinea-pig, rabbit, dog, monkey, bovine and pig. Using a highly sensitive and specific method developed for the determination of histamine using high-performance liquid chromatography, HA was detected in the retinas of all species examined. HA content ranged from 11 (bovine) to 540 pmole/g wet tissue (dog), and HDC activity ranged from 2 (rabbit) to 150 (dog) fmol HA synthesized/min/mg protein. With the exception of the dogs, the retinal values were one order lower than those in the brain in all species examined. The canine retinas had the high HA and HDC values among the species examined, and were approximately equal to those in the brain. However, the ratios of HDC activity to HA content ranged from 0.04/min to 0.51/min. These values resembled those in the brain and were much higher than those in mast cells. This suggests that histamine in the retinas exists mainly in the neurons even though the actual amounts are small and may be involved in the physiological and the pathological responses in mammalian retinas.

Animals↗
PubMed1991

Repeated dose toxicity studies on catena-(S)-[mu-[N alpha-(3-aminopropionyl) histidinato(2-)-N1,N2,O:N tau]-zinc] in rats.

Thirteen- and 52-week oral toxicity studies of Z-103 (catena-(S)-[mu- [N alpha-(3-aminopropionyl) histidinato (2-)-N1,N2,O:N tau]-zinc], CAS 107667-60-7) were carried out in rats. In a 13-week repeated dose toxicity study (37.5, 75, 150, 300, 600 or 1200 mg/kg/d), deterioration of the general condition was observed at 300 mg/kg/d or more, a decrease in body weight gain at 600 mg/kg/d or more. Approximately 40% of the animals were found dead or sacrificed in a moribund state at 1200 mg/kg/d. Furthermore, in the 600 mg/kg group changes in urine volume, blood urea nitrogen and weight of kidneys were observed, suggesting that Z-103 may have had adverse effects on the kidney. No sex difference was noted. From these results the no-effect dose level was estimated to be 150 mg/kg/d under the conditions of this experiment. In a 52-week repeated dose toxicity study (18.75, 37.5, 75 or 150 mg/kg/d), proliferation of small duct and atrophy of acinar cells in the pancreas were observed in both sexes of the 150 mg/kg/d group. No other dose-related changes were observed throughout the administration period. Therefore, the no-effect dose level was estimated to be 75 mg/kg/d under this condition.

Animals↗
PubMed1991

Antigenicity studies on catena-(S)-[mu-[N alpha-(3-aminopropionyl)histidinato(2-)-N1,N2,O:N tau]-zinc].

The antigenicity of Z-103 (catena-(S)-[mu[N alpha-(3-aminopropionyl) histidinato(2-)-N1,N2,O:N tau]-zinc], CAS 107667-60-7) was evaluated using the following assay procedures: 1. active systemic anaphylaxis (ASA) in guinea pigs. 2. passive cutaneous anaphylaxis (PCA) in guinea pigs with serum from guinea pigs sensitized with Z-103, 3. delayed type skin reaction (Maximization Test) in guinea pigs, 4. passive cutaneous anaphylaxis (PCA) in rats with serum from mice sensitized with Z-103 and 5. passive hemagglutination (PHA) with serum from mice sensitized with Z-103. In each test except for Maximization Test, the sera obtained 1 or 6 h (hereinafter designated as 1-h-sera or 6-h-sera) after a single oral administration of 500 mg/kg of Z-103 to the unused rats, guinea pigs or rabbits, were used as the challenge antigen. 1. ASA in guinea pigs: No anaphylaxis reaction was observed in any of the sensitized guinea pigs by elicitation with challenge antigen. 2. PCA in guinea pigs: PCA titer of sera from all the sensitized animals was less than 1 in elicitation with the challenge antigen. 3. Delayed type skin reaction test: No skin reaction was observed in sensitized guinea pigs after intradermal injection or dermal application of Z-103. 4. PCA in rats: PCA titer of sera from BALB/c and C3H/He mice sensitized with Z-103 was less than 5 in elicitation with the challenge antigen. 5. PHA reaction: When erythrocytes coated with challenge antigen were added to sensitized sera, the hemagglutination titer was less than 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaphylaxis↗
PubMed1991

[A study of urinary immunoglobulins and electrolyte excretion after lordosis].

We described a transient low or non-selective proteinuria after forced lordosis as a characteristic of orthostatic proteinuria and the heteroporous theory and sieving function theory which might explain the mechanism of orthostatic proteinuria. The angiogenic action of the renin-angiotensin system played an important part in these theories. Angiotensin II was recognized as the key regulator of renal sodium excretion, because it reduced the urinary Na/K ratio. Since the purpose of this study is to investigate the influence of the renin-angiotensin system on the mechanism of orthostatic proteinuria, proteins and electrolytes in the urine were examined before and after lordosis in 9 healthy children (Group A) and in 6 children with orthostatic proteinuria (Group B). The urinary ratio of protein/creatinine (P/cre) in Group B was already significantly higher than that in Group A before lordosis and significantly increased after lordosis, while P/cre in group A did not increase after lordosis. The urinary Na/K ratio (Na/K) in Group B was already significantly lower than that in Group A before lordosis, and after forced lordosis, Na/K in Group A decrease with no difference between both groups observed. It is suggested that a significant increase on P/cre after lordosis was obtained only in Group A, whereas in both groups the renal vein may be compressed by forced lordosis and as a result angiotensin II may be stimulated. There might be a difference of the responsibility to angiotensin II in glomerular mesangium contraction between both groups.

Adolescent↗
PubMed1991

The effect of pulmonary arterial flow and positive end-expiratory pressure on retrograde bronchial mucosal blood flow.

Bronchial viability within the first few days after lung transplantation depends on collateral blood flow from the pulmonary to the bronchial circulation. In the present study the relationship between pulmonary arterial flow and retrograde bronchial blood flow, and the effect of positive end-expiratory pressure on bronchial blood flow were evaluated by laser Doppler velocimetry in an isolated in situ lung perfusion model. Nine adult mongrel dogs were exsanguinated by way of a left atrial cannula. Blood was pumped by a roller pump into the main pulmonary artery. Lungs were perfused at random flow (in 0.5 L/min increments) at rates of 1 to 3 L/min. Steady-state laser Doppler velocimetric measurements at each level of flow were made at the tracheal carina and both bronchial carina. Pump flow was then set at baseline cardiac output and positive end-expiratory pressure was applied. Steady-state laser Doppler velocimetric measurements were obtained at each level of positive end-expiratory pressure (5 cm H2O and 10 cm H2O). Bronchial blood flow correlated well with pulmonary arterial flow (for the tracheal carina; rs = 0.912 and p less than 0.0005; for the right bronchial carina, rs = 0.799, p less than 0.0005; for the left bronchial carina, rs = 0.917, p less than 0.0005; where rs is the common correlation coefficient). The bronchial blood flow at the left bronchial carina and the right bronchial carina were significantly higher than at the tracheal carina (p less than 0.005 and p less than 0.05, respectively). At baseline cardiac output, bronchial blood flow in the in situ model was approximately 50% lower than observed in the intact animals. Positive end-expiratory pressure increased the bronchial blood flow at the tracheal carina and both bronchial carina (p less than 0.05).

Animals↗
PubMed1991

[Effect of short-term administration of medroxyprogesterone acetate on side reactions of combination chemotherapy with ADR, VDS and CDDP in primary lung cancer].

The effect of short-term (10 days) Medroxyprogesterone acetate (MPA) administration on side reactions of combination chemotherapy with ADR, VDS and CDDP for primary lung cancer was studied by comparisons of MPA administration group (20 cases) with non administration group (30 cases). 1) Frequency of vomiting, duration of nausea and body weight loss were significantly improved in MPA administration Group (p less than 0.01). 2) Leukocyte and neutrophil counts in MPA administration group especially 7-10 days after of chemotherapy were maintained higher than these of non administration group (p less than 0.05). 3) Major side effects including thromboembolism in MPA administration group had not been observed. These results indicated that short-term MPA administration was relatively safe and effective in combination chemotherapy including CDDP.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[Cytoskeleton anomalies in disorders of red cell membrane proteins].

Cytoskeletal abnormalities in red cells were studied in 250 patients at our laboratory, especially on hereditary elliptocytosis (HE), hereditary spherocytosis (HS), and band 4.2 anomalies. First of all, on HE, we have found two patients of a dominantly-inherited trait of a new beta-spectrin variant with 216 kDa peptide. The contents of abnormal beta'-spectrin to the total spectrins were 7.6% in propositus, and 10.5% in her mother. As a functional abnormality, abnormal alpha beta'-spectrin dimer could not be converted to tetramer in both patients. Thus, our patients may differ from HE Nice. Secondarily, the causal relationship between red cell ankyrin and spectrin was studied on a typical HS case with abnormal chromosome, del (8p11.2-8p21.1). In this case, the deleted genetic locus was involved with loci of genes for SPH1 and ankyrin. The contents of ankyrin and other red cell membrane proteins, however, appeared to be normal on SDS-PAGE. In addition, as a unique disorder in Japan, unrelated five cases of membrane protein 4.2 deficiency were found at our laboratory. In these cases, the characteristic features were; 1) clinically uncompensated hemolysis, 2) ovalostomatocytosis, 3) markedly decreased deformability of the intact red cells by ektacytometry, if heat-treated, 4) two peptides of membrane protein 4.2 were detected in a trace amount by Western blot. Five phenotypes were categorized by Western blot, as based on the type of membrane protein 4.2 present; 1) 72 kDa peptide alone, 2) 72 kDa + 74 kDa in a trace amount, 3) 72 kDa + 74 kDa both in a trace amount, 4) 72 kDa + 68 kDa in a trace amount, and 5) complete deficiency.

Ankyrins↗