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Biomedical subjects

Y Maeda

Publications and source records attributed to Y Maeda.

At least 1,153 records · Page 64Linked to original sources
PubMedDate not supplied

The occurrence of precipitating antibodies in transfused Japanese patients with hereditary ninth component of complement deficiency and frequency of C9 deficiency.

Antibodies to the ninth component of complement (C9) were found in a patient with hereditary C9 deficiency (C9D) who had received multiple transfusions. The incidence of anti-C9 precipitating antibodies following transfusion was investigated in 63,625 patients treated at Kyushu University Hospital, and 475,886 blood donors at the Fukuoka Red Cross Blood Center were studied to determine the frequency of C9D in Japan. Transfusion reactions in recipients having anti-C9 were also monitored. One hundred and eighty-six subjects (15 patients and 171 donors) with C9D were identified (a prevalence of 0.036%). Four of 15 C9-deficient patients had received transfusions. One of the patients who had received several units of blood within 1 week developed low-titer C9-precipitating antibody. This patient was transfused in the presence of the antibody without evidence of adverse reactions. No precipitating antibody was detected in the remaining three patients who had received several units of blood on a single day. These observations suggest that multiple transfusions may contribute to the development of anti-C9.

Chemical Precipitation↗
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Preparation of white-cell-poor blood components using a quadruple bag system.

A method for the preparation of white-cell-poor red cells from 400 ml of blood collected in a quadruple bag with one 80-ml and two 300-ml satellite bags is described. In this procedure, a platelet concentrate was prepared from the buffy coat fraction obtained by the first centrifugation of whole blood. After centrifugation of whole blood for 5 minutes at 3500 X g, the plasma was transferred into the 300-ml bag until the interface of red cells and plasma reached a level 32 mm from the top of the bag; then approximately 70 g of plasma and buffy coat were collected into the 80-ml bag. The buffy coat fraction was centrifuged further for 5 minutes at 170 X g, and the supernatant (concentrated platelets in plasma) was transferred into the second 300-ml bag. In this blood processing, the recovery of red cells into the packed red cells and of platelets into the platelet concentrate was 93 +/- 4 percent and 52 +/- 13 percent, respectively, of the original value. White cells in the packed red cells were 70 +/- 28 X 10(7) with recovery of 32 +/- 9 percent of the original value, and the lymphocytes in the white cells were only 7 +/- 5 X 10(7) (7 +/- 4% of the original value). White cell contamination of platelet concentrate was below the threshold of white cell detection by the microcell counter (less than 300 cells per microliter of concentrate).

Blood Cells↗
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Prevention of acquired defects in platelet function during blood processing.

Two kinds of platelet concentrates were prepared in this study: one as pelleted platelets from platelet-rich plasma (PCs), and the other as a platelet suspension from the buffy coat fraction (nonpelleted PCs). The characteristics of both platelet concentrates were studied. White cell contamination in the nonpelleted PCs was below the threshold of detection by a microcell counter (less than 300 cells/microliter of concentrate); in the pelleted PCs, it was 3 +/- 1 x 10(7) cells per concentrate. The difference between the white cell contamination in pelleted PCs and nonpelleted PCs was significant (p less than 0.001). The degree of aggregation induced in pelleted PCs by ADP (9 microM) and collagen decreased to 33 and 55 percent, respectively, of that in platelet-rich plasma. The secondary wave of platelet aggregation induced by ADP and epinephrine was absent in pelleted PCs, and ATP secretion from these platelets by ADP stimulation also decreased remarkably. However, the degrees of aggregation and ATP secretion in nonpelleted PCs were similar to those in platelet-rich plasma. Furthermore, it was found that the amount of platelet factor 4 release seen in pelleted PCs was large in comparison to that in nonpelleted PCs and platelet-rich plasma. These results suggested that the deterioration of platelet function might have resulted from the platelet activation induced by pellet formation during the preparation of PCs from platelet-rich plasma.

Adenosine Triphosphate↗
PubMedDate not supplied

High-dose chemotherapy with hematopoietic stem cell transplantation is effective for nasal and nasal-type CD56+ natural killer cell lymphomas.

CD56+ natural killer (NK) cell lymphomas occur frequently in the nasal and nasopharyngeal regions and carry a poor prognosis. We have studied seven cases with NK-cell lymphomas. These lymphomas showed the following immunophenotype: CD56+, CD2+, sCD3- and Epstein-Barr virus-encoded small RNAs (EBERs)+. Six patients had localized (stage I or II) disease involving the nasopharyngeal region, while one had stage III disease. One patient with stage I disease achieved a complete remission (CR) after treatment with involved-field irradiation, but subsequently relapsed and died. The remaining six patients received combination chemotherapy as primary treatment: five patients with localized stage I or II disease and one patient with advanced stage III disease. Responses to initial chemotherapy were generally poor. These six patients received a variety of salvage chemotherapy regimens, but never achieved a CR. Subsequently, four of six patients showed a highly aggressive clinical course and died of disseminated disease within 1 year from the diagnosis. Three of six patients received high-dose chemotherapy supported by syngeneic, autologous or allogeneic peripheral blood stem cell transplantation. Two of the three transplant patients achieved a CR and are now surviving in continuous CR. Our clinical experience suggests that myeloablative high-dose chemotherapy and bone marrow rescue by hematopoietic stem cell transplantation may be an effective salvage treatment modality for refractory NK-cell lymphomas and could be considered as a part of the initial therapy for these patients.

Adolescent↗
PubMedDate not supplied

The effects of intraperitoneal injection of 6-hydroxydopamine on the turnover and the levels of the brain catecholamines and the levels of plasma corticosterone in rats.

1. The effects of intraperitoneal injection of 6-hydroxydopamine (6-OHDA) on the levels and the turnover of brain catecholamines and the levels of plasma corticosterone were studied in rats. 2. Two weeks after intraperitoneal injection of 6-OHDA (150 mg/kg) a virtually complete disappearance of cardiac noradrenaline was observed. 3. An increment and an accelerated turnover of noradrenaline in the hypothalamus was observed 2 weeks after peripheral administration of 6-OHDA (150 mg/kg). 4. There was no change in the levels and the turnover of noradrenaline in the cortex of the rats so treated. 5. There was not change in the levels and the turnover of dopamine in either the hypothalamus or the cortex of the 6-OHDA-treated rats. 6. An increment and an accelerated turnover of hypothalamic noradrenaline were not associated with any change in plasma corticosterone.

Animals↗
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Gene transfer into rat renal cells using adeno-associated virus vectors.

Adeno-associated virus (AAV) vectors have a number of attractive features, including lack of cytotoxicity, ability to transduce nondividing cells, and long-term transgene expression. We investigated whether rat renal cells could be efficiently transduced with AAV vectors. Rat glomerular mesangial cells were transduced with AAV-lacZ vector containing beta-galactosidase gene in vitro, and the expression of beta-galactosidase was evaluated by X-gal staining and ELISA. For ex vivo experiments, sections of rat kidneys were incubated with AAV-lacZ, and then evaluated by X-gal histochemical staining. The level of beta-galactosidase expression in cultured rat mesangial cells increased in a dose-dependent manner (ranging from 1 x 10(5) to 5 x 10(6) particles/cell). When transduced with 5 x 10(6) vector particles/cell of AAV-lacZ, about 50% of mesangial cells were stained positively with X-gal, and the level of beta-galactosidase expression reached 9.9 +/- 1.5 ng/mg protein. Expression was detectable during the culture period for at least 7 days. X-gal histochemical examination of the ex vivo transduced renal tissue revealed tubular cell and interstitial tissue staining. However, gene transfer was not clearly observed in glomeruli. These findings suggest that AAV vectors have the potential for gene therapy of renal diseases.

Animals↗
PubMedDate not supplied

Effects of mianserin on human sleep.

Sleep EEG and nocturnal penile tumescence (NPT) were investigated in 6 healthy men during placebo and mianserin administration and after mianserin withdrawal. The results were assessed in a historical comparison with those previously obtained with clomipramine. With mianserin, REM sleep was suppressed slightly. However, the suppressive effect of mianserin on REM sleep--based on the historical comparison--was significantly weaker than that of clomipramine throughout all the drug nights. Accordingly, a rebound increase in REM sleep was not observed after withdrawal. Less suppressive effects on NPT and disturbance of sexual function with mianserin than with clomipramine were observed. We suggest that a correlation between the prolonging effect on REM latency and the clinical antidepressant effect is limited to some antidepressants.

Adolescent↗
PubMedDate not supplied

Cytologic features of pleural effusion in apocrine sweat gland carcinoma. A case report.

BACKGROUND: Carcinoma arising in the apocrine sweat glands is very rare, and there are few reports of the cytologic features. We encountered a case of metastatic apocrine carcinoma in a pleural effusion. CASE: A 46-year-old male had a dark reddish nodule in the right axillary region that was diagnosed as apocrine carcinoma of skin appendage origin. Three years after wide resection and chemotherapy, widespread metastases developed with a massive pleural effusion. Needle aspiration fluid cytology contained clusters of adenocarcinoma. Some tumor cells had abundant cytoplasm or periodic acid-Schiff-positive, coarse granules. Decapitation secretion was occasionally found on the cell surface. Immunohistochemically, the tumor cells were often positive for BRST-2 and BRST-3. CONCLUSION: Cytologic features of metastatic apocrine sweat gland carcinoma show some characteristics of adenocarcinoma. Moreover, its definitive diagnosis in a pleural effusion can be made because of retaining the characteristics of apocrine sweat gland.

Apocrine Glands↗
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Levels in stroke patients of CSF astroprotein, an astrocyte-specific cerebroprotein.

Astroprotein (an astrocyte-specific cerebroprotein) levels in cerebrospinal fluid (CSF) were determined by radioimmunoassay in 47 stroke patients. (Astroprotein is immunologically identical to glial fibrillary acidic protein.) Astroprotein levels in CSF increased markedly in acute cases of intracerebral hemorrhage and slightly to moderately in some acute cases of subarachnoid hemorrhage and cerebral infarction. In intracerebral hemorrhage, CSF astroprotein levels in the acute stage of the ictus reflected the size of the lesion and were used to estimate the clinical outcome. In subarachnoid hemorrhage and cerebral infarction, CSF astroprotein levels were related to the general neurological state. Evidence obtained indicated that fundamentally different destructive and/or degenerative processes in the brain may be involved in intracerebral hemorrhage, subarachnoid hemorrhage and cerebral infarction and that determination of CSF astroprotein may have clinical significance in stroke patients.

Acute Disease↗
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Responses of isolated canine basilar artery and human platelet to chlorpromazine and amitriptyline.

Sustained contraction of isolated canine basilar artery was induced by addition of prostaglandin F2 alpha, prostaglandin E2, hemoglobin-containing solution, or serum. Human platelet aggregation was induced by 1.0 microM adenosine diphosphate. The sustained contraction of basilar artery and the aggregation of platelet, particularly its secondary aggregation, were inhibited in a dose-dependent manner by addition of chlorpromazine or amitriptyline; calmodulin antagonist. The molar concentrations at 50% inhibition by chlorpromazine or amitriptyline were 5.9 to 7.7 microM or 28 to 39 microM for the contraction of basilar artery and 57 microM or 111 microM for the secondary aggregation of platelet. The results were discussed mainly on the basis of interaction of psychotropic drugs and Ca2+, calmodulin-dependent enzymes, particularly myosin light chain phosphorylation.

Adenosine Diphosphate↗
PubMedDate not supplied

Effect of selective inhibitor of thromboxane A2 synthetase on experimental cerebral vasospasm.

Experimental cerebral vasospasm was induced in the canine basilar artery by an intracisternal injection of fresh autogenous arterial blood. Delayed vasospasm was defined as a reduction to less than 75% of the caliber of control basilar artery 5 days after the intracisternal blood injection. A selective inhibitor of thromboxane A2 synthetase, sodium(E)-3-[4-(3-pyridylmethyl) phenyl]-2-methyl-2-propenoate, was infused intravenously for 1 or 2 hrs at 50 micrograms/kg/min in normal animals exhibiting vasospasm. Angiographic evidence of cerebral vasospasm was not reversed. Mean regional cerebral blood flow was not significantly increased in normal and vasospastic animals, but a mean difference of regional cerebral blood flow was significantly increased only in vasospastic animals. Mean arterial blood pressure and pulse rate were not seriously changed in normal and spastic animals. Another selective thromboxane A2 synthetase inhibitor, (E)-3-[4-(1-imidazolylmethyl)phenyl]-2-propenoic acid hydrochloride monohydrate, showed a similar effect on the caliber of the basilar artery, regional cerebral blood flow, blood pressure, and pulse rate, in vasospastic animals. Venous blood was taken from the internal jugular vein, and the mean platelet aggregation induced by 10 micrograms/ml of collagen was inhibited by the infusion of either selective inhibitor at 50 micrograms/kg/min for 2 hrs. However, mean platelet aggregation rates in vasospastic animals before and after treatment with either selective inhibitor were not significantly different to those in normal animals.

Animals↗
PubMedDate not supplied

Effect of 5-lipoxygenase inhibitor on experimental delayed cerebral vasospasm.

Experimental delayed cerebral vasospasm was produced in canine basilar arteries by 2 successive injections, 2 days apart, of fresh autogenous arterial blood into the cisterna magna. When angiographic evidence of delayed vasospasm was confirmed 7 days after the initial intracisternal blood injection, a selective inhibitor of 5-lipoxygenase, 2-(12-hydroxydodeca-5,10-diynyl)-3,5,6-trimethyl-1,4-benzoqu inone (AA-861), was infused intravenously at 6.5 X 10(-4) mg/kg/min for 2 hours. However, angiographic evidence of delayed vasospasm was not reversed, and mean regional cerebral blood flow was not significantly increased. In other studies, oral doses of AA-861 at 100 mg/kg/day were given twice a day for 7 days after the initial intracisternal blood injection. In the treated group, angiographic evidence of delayed vasospasm was significantly reduced, and the contractile property of excised basilar arteries in response to vasoconstrictor agents was significantly improved. It is suggested that leukotrienes, 5-lipoxygenase products of arachidonic acid, might be important etiologic factors responsible for the development of delayed vasospasm and that AA-861 would have a therapeutic effect not on the reduction of delayed vasospasm once developed but on the prevention of the development of delayed vasospasm.

Administration, Oral↗
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Animal pharmacological effects of 24R,25-dihydroxyvitamin D3 one of the endogenous substances regulating calcium metabolism.

Lewis lung carcinoma was found to cause hypercalcaemia in tumour-bearing mice. 24R,25-Dihydroxyvitamin D3, a naturally occurring steric epimer, significantly prolonged the survival time of mice with Lewis lung carcinoma. It also had an analgesic effect in mice with Lewis lung carcinoma and increased the strength of bone weakened by the carcinoma which causes abnormal calcium metabolism and results in hypercalcaemia.

24,25-Dihydroxyvitamin D 3↗
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Effect of 24R,25-dihydroxyvitamin D3 in experimental renal insufficiency.

This placebo-controlled study in JCL-Wistar rats showed that 100 micrograms/kg 24R,25-dihydroxyvitamin D3, when given for 12 days consecutively, restored immune function which had deteriorated following aminonucleoside-induced nephrosis. Urinary creatinine excretion in five-sixths nephrectomized rats was also shown to be increased by 10 micrograms/kg 24R,25-dihydroxyvitamin D3. Hypophosphataemic effects in both these cases of experimentally-induced renal insufficiency was also shown following administration of 24R,25-dihydroxyvitamin D3.

24,25-Dihydroxyvitamin D 3↗
PubMedDate not supplied

Effect of 24R,25-dihydroxyvitamin D3 in experimental diabetic rats.

The results are presented of a controlled study in male Wistar rats into the effects of 24R,25-dihydroxyvitamin D3 on blood glucose levels, bone calcium content and ADP-induced platelet aggregation in streptozocin-induced diabetes mellitus. Blood glucose levels were shown to be decreased by 10 micrograms/kg 24R,25-dihydroxyvitamin D3. The reduced bone calcium content associated with diabetes mellitus was returned to normal levels with both 1 and 10 micrograms/kg 24R,25-dihydroxyvitamin D3. It was also shown to exhibit dose-dependent anti-platelet activity. The data suggest that 24R,25-dihydroxyvitamin D3 might have potential as a mild therapeutic agent in the treatment of osteoporosis and platelet hyperactivity associated with diabetes mellitus.

24,25-Dihydroxyvitamin D 3↗
PubMedDate not supplied

Effects of vitamin D3 metabolites in ovariectomized rats.

The effects of two vitamin D3 metabolites, 24R,25-dihydroxyvitamin D3 and 1 alpha,25-dihydroxyvitamin D3, were investigated in ovariectomized rats. The amount of ash in the femur on a defatted dry weight basis was significantly greater in rats treated with 1 microgram/kg 24R,25-dihydroxyvitamin D3, or 0.01 or 0.1 microgram/kg 1 alpha,25-dihydroxyvitamin D3 than in the controls. The concentration of bone gla protein in serum and amounts in the femur were significantly greater in rats treated with 1 or 10 micrograms/kg 24R,25-dihydroxyvitamin D3, but not those given 1 alpha,25-dihydroxyvitamin D3 compared with the controls. These results suggest that 24R,25-dihydroxyvitamin D3 increased bone mass probably through the stimulation of bone formation.

24,25-Dihydroxyvitamin D 3↗
PubMedDate not supplied

Genetic similarity and relationships of DNA fingerprints with performance and with heterosis in Japanese quail lines from two origins and under reciprocal recurrent or within-line selection for early egg production.

DNA fingerprints of Japanese quail male and female pure line breeders were obtained with probes 33.6, 33.15, and R18.1 and they yielded a total of 59 scoreable bands. Bandsharing (0<BS<1) was calculated within and between six quail lines of two origins, and under reciprocal recurrent (AA and BB), within-line (DD and EE) or no (PP and FF) selection. Twenty one pair types were compared. BS was 0.30 higher within line than between lines. BS with the control line was smaller for reciprocal recurrent selection lines than for lines under individual selection. Bandsharing between the two reciprocal recurrent selection lines was 0.19 lower than between lines under individual selection. These results indicate that the two selection methods had different effects on the genetic constitution of the lines, in agreement with previous observations made from the analysis of biochemical polymorphisms with the same set of birds. Egg production and weight traits of pure and crossbred progeny from fingerprinted quail were obtained and compared, and a linear relationship with the measure of bandsharing was estimated. No significant regression coefficient of performance on BS was found over all progeny genetic types. Heterosis from individual matings could also be estimated under the two selection methods since the same birds were parents of both pure and crossbred performance-tested quail. The association of heterosis with the difference between BS of parents of the purebreds and BS of parents of their half-sib crossbreds was favourable and significant for early production traits in lines DD and EE, but no relationship was found in lines AA and BB. These results indicate that the high level of heterosis obtained through reciprocal recurrent selection, and the heterosis observed under within-line selection may have, partly at least, a different genetic determinism. Therefore, the relationship of heterosis with BS may also depend on the past history of selection in the lines.

Journal Article↗