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Biomedical subjects

M Abe

Publications and source records attributed to M Abe.

At least 703 records · Page 39Linked to original sources
PubMed1994

Presence of C5a-potentiating activity in the plasma of a patient with Kimura's disease.

To determine whether the response to the active complement fragment C5a in polymorphonuclear leukocytes (PMN) obtained from a patient with Kimura's disease is similar to that in normal subjects, we evaluated superoxide anion (O2-) generation after stimulation with C5a. The patient's PMN produced more O2- than did those from healthy controls after stimulation with human C5a in vitro. The response returned to normal with the improvement in clinical indicators after initiation of steroid administration. We conducted the following experiments with the plasma of this patient during the active disease stage to establish the presence of a humoral factor that potentiated the C5a-response of PMN. Incubation of PMN from normal controls having the same blood type as the patient at 37 degrees C for 2 h with the patient's plasma at the active disease stage revealed that the cells generated abundant O2- after stimulation with C5a. Incubation of normal PMN with the patient's plasma during the inactive disease stage showed no potentiated response to C5a. This activity was lost after incubation at 56 degrees C for 30 min. Coincubation of PMN with methylprednisolone up to 100 micrograms/ml did not suppress this activity. Although the plasma concentration of C5a at the active stage was mildly elevated (13 ng/ml), it was below the limit of detection (< 10 ng/ml) at the inactive stage. These results suggest the presence of a heat-labile, humoral factor in the patient's plasma that upregulated the response of PMN to C5a and that was not suppressed by in vitro treatment with a steroid. This factor may influence the acute inflammatory reaction in this disorder.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1994

An immunohistochemical study of Warthin-Finkeldey cells in measles.

An autopsy case of an 18 month old male infant with measles infection is reported. An autopsy revealed generalized lymphadenopathy, splenomegaly and hyperplastic thymus. Histologically, there were many Warthin-Finkeldey cells (WFC) in hyperplastic lymphoid tissues. Although viral particles and inclusions were not detected electronmicroscopically, the infection of measles virus was detected in WFC by immunofluorescent technique using anti-measles antibody. Warthin-Finkeldey cells were morphologically and immunohistochemically divided into two groups. The first type was WFC appearing in the germinal centers of lymphoid tissue, revealing many large nuclei and B cell markers. The second type was WFC appearing in the interfollicular areas and thymus, showing many small hyperchromatic nuclei and T cell markers. The data indicate that there might be a morphologic and immunophenotypic heterogeneity in WFC.

Autopsy↗
PubMed1994

Inhibitory effect of melatonin on cataract formation in newborn rats: evidence for an antioxidative role for melatonin.

We evaluated the inhibitory effect of melatonin, a recently discovered scavenger of free radicals, on cataract formation in the newborn rat. The glutathione synthesis inhibitor, buthionine sulfoximine (BSO) (3 mmol/kg), was intraperitoneally injected into newborn rats for 3 consecutive days starting on day 2 after birth. These glutathione depleted rats develop cataracts. Melatonin (4 mg/kg) was injected intraperitoneally into half of the rats once a day beginning at day 2 after birth; the other half of the animals received solvent daily. The incidence of cataract was observed on day 16, after the eyes of the newborn animals had opened. Both reduced glutathione (GSH) and oxidized glutathione (GSSG) levels were measured. Cataracts were observed in all animals (18/18) treated with BSO plus solvent. The incidence of the cataract in the animals cotreated with melatonin was only 6.2% (1/15). Total lenticular glutathione (GSH + GSSG) levels in BSO only treated rats were reduced by 97%. The total glutathione in the lens of the BSO plus melatonin group was significantly higher (by 3%) than that of the BSO only group. The percentage of the total glutathione as GSSG for the BSO plus solvent group was higher than the control value. Cotreatment of BSO injected rats with melatonin (4 mg/kg/day) clearly reduced cataract formation proving that it is directly or indirectly protective against oxidative stress which accompanies glutathione deficiency. The inhibitory effects of melatonin on cataract formation in this study could be due to melatonin's free radical scavenging activity or due to its stimulatory effect on glutathione production.

Animals↗
PubMed1994

A new detection method for the K variant of butyrylcholinesterase based on PCR primer introduced restriction analysis (PCR-PIRA).

The K variant of human butyrylcholinesterase is caused by a G/A transition in the butyrylcholinesterase gene, which neither creates nor destroys any restriction site. In an attempt to detect the K variant both simply and rapidly, we developed a two step method of "PCR primer introduced restriction analysis" (PCR-PIRA). The first step was used to introduce a new Fun4HI site into the normal allele for a screening test, while the second step was performed to create a new MaeIII site on the variant allele for a specific test. This method thus enabled us to distinguish clearly the K variant from the normal allele, and also showed that the frequency of the K variant allele is 0.164 in the Japanese population.

Alleles↗
PubMed1994

Two distinct types of reticular cells in the pig sheathed artery.

The morphology of reticular cells of the sheathed arteries, in the red pulp of pig spleen, was studied by using transmission electron microscopy; and their histochemical reactivity with periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP). The phagocytic ability was evaluated by injecting colloidal carbon into the splenic artery. Reticular cells of the sheathed arteries were classified as type I and type II cells. Type I cells have a nucleus with scanty chromatin, and the cytoplasm reacts positively to PA-TCH-SP. The PA-TCH-SP-positive granules are considered to be subunits of beta-glycogen particles based on their morphological features. Type II cells have a nucleus with abundant chromatin and are not stained by PA-TCH-SP. Both types of reticular cells are connected with reticular fibers. Results of the colloidal carbon injection showed that type I reticular cells did not ingest carbon particles during the time frame of the experiment, whereas type II reticular cells are phagocytic and ingested carbon.

Animals↗
PubMed1994

Specific induction of LTC4 synthase by retinoic acid in rat basophilic leukemia-1 cells.

Overnight (10-16 h) incubation of retinoic acid (RA), a derivative of vitamin A, specifically induced LTC4 synthase activity (5 to 10-fold), but not LTA4 hydrolase activity in the lysate of rat basophilic leukemia-1 (RBL-1) cells. A time course study revealed that the increase of LTC4 synthase activity was time dependent and that the peak value was obtained after a 24-hour incubation with RA. The induction of enzyme activity was specifically localized to the microsomal fraction. Glutathione (GSH) S-transferase activity measured by using the same cell lysate as an enzyme source and 1-chloro-2,4-dinitrobenzene (DNCB) as a substrate was not influenced by RA treatment, indicating that the induction by RA is specific for membrane-bound LTC4 synthase. The induction of LTC4 synthase may be an important regulatory mechanism of peptide-LT synthesis in allergy and inflammatory diseases.

Animals↗
PubMed1994

Enhancement of chemosensitivity of quiescent cell populations in murine solid tumors using nicotinamide.

Cis-diamminedichloroplatinum(II) (CDDP) was intraperitoneally injected into mice bearing SCC VII or EMT6/KU tumors after 10 administrations of 5-bromo-2'-deoxyuridine (BUdR) to label all the proliferating tumor cells. One hour later, the tumors were excised, minced and trypsinized. The tumor cell suspensions were incubated with cytochalasin B (a cytokinesis blocker). The micronucleus (MN) frequency was determined using immunofluorescence staining to BUdR. The cells that were not labeled with BUdR could be regarded as the quiescent cells. The MN frequency in total tumor cells was determined from the tumors that were not pretreated with BUdR. To modify the sensitivity to CDDP, nicotinamide was intraperitoneally injected before CDDP administration. In both tumor system, the MN frequency in quiescent cells was lower than in total cells. Nicotinamide pretreatment increased the MN frequency in total and quiescent cells in both tumor systems, especially in total cells of the SCC VII tumor. The nicotinamide injection increased the uptake of 195mPt-CDDP into the total cells, especially in the SCC VII tumor. Nicotinamide administration before chemotherapy using CDDP was considered to be effective for tumor control, especially in tumors including large acutely hypoxic fractions such as the SCC VII murine tumor.

Animals↗
PubMed1994

Brushing-induced effects with and without a non-fluoride abrasive dentifrice on remineralization of enamel surfaces etched with phosphoric acid.

The remineralization of acid-etched enamel after brushing with and without a non-fluoride abrasive dentifrice was investigated using scanning electron microscopy after sodium hypochlorite (NaOCl) or ethylenediamine tetra-acetic acid treatment, of the specimens. Ground enamel pieces were etched with 30% phosphoric acid for 60 s and attached to resin plates. They were exposed to the oral environment of 4 subjects for 8 weeks and brushed for 1 min daily. Paste and brushing caused the acid-etched enamel to erode selectively, i.e., deep grooves were formed in the prism peripheral regions, while projections of the prism bodies showing a relatively low density of crystallites were retained. Brushing without dentifrice, on the other hand, caused about 0.5 micron thick pellicle with tag-like structures to cover the etched enamel. Fine mineral granules, presumably derived from saliva and minute fragments of etched crystallites, were precipitated on the enamel surface as a thin layer with the pellicle. These results indicate that daily brushing without dentifrice induces the remineralization of acid-etched enamel by depositing salivary components, while paste brushing will lead to abrasion of the weakened enamel.

Acid Etching, Dental↗
PubMed1994

Myocardial scintigraphic characteristics in patients with primary aldosteronism.

To evaluate the difference in myocardial damage between primary aldosteronism and untreated essential hypertension, we performed thallium-201 myocardial single-photon emission computed tomography in 10 patients with primary aldosteronism and 10 patients with essential hypertension who were matched for age, sex, blood pressure, and the severity of left ventricular hypertrophy for primary aldosteronism. From the analysis of thallium-201 myocardial scintigraphy, extent score was calculated. Extent score was significantly higher in primary aldosteronism than in essential hypertension (45.8 +/- 23.5% versus 9.5 +/- 7.3%, P < .01). After operation, blood pressure significantly decreased, and the precordial voltages (SV1 + RV5) and left ventricular mass indexes were significantly reduced in patients with primary aldosteronism. Extent score was also significantly improved. These results suggest that despite the same severity of myocardial hypertrophy between primary aldosteronism and essential hypertension, the myocardial damage estimated by thallium-201 myocardial scintigraphy is more severe in primary aldosteronism than in essential hypertension. Extent score was useful for evaluation of the severity of myocardial damage in hypertensive patients.

Echocardiography↗
PubMed1994

Evidence against a role of insulin in hypertension in spontaneously hypertensive rats. CS-045 does not lower blood pressure despite improvement of insulin resistance.

Hyperinsulinemia resulting from peripheral insulin resistance has been demonstrated both in spontaneously hypertensive rats (SHR) and in humans with essential hypertension. A new class of antidiabetic drugs, thiazolidinediones, which can improve insulin resistance, may be able to lower not only blood glucose levels but also blood pressure. The present study was therefore designed to clarify the proportion of SHR that are glucose intolerant and to observe the effect on blood pressure of CS-045 (troglitazone) administered at 70 mg/kg per day for 2 weeks to male SHR (n = 13). Among 67 male 8-week-old SHR, 74.6% were glucose intolerant and hyperinsulinemic. Systolic blood pressure did not correlate with plasma glucose or insulin levels before or after glucose loading. Treatment with CS-045 improved insulin resistance, as evidenced by a smaller area under the curve of plasma glucose and insulin levels in response to glucose loading. However, systolic blood pressure was not altered. When the data were reanalyzed according to the presence or absence of glucose intolerance before the treatment, blood pressure in the treated group was the same as in controls despite significant improvement in steady-state plasma glucose levels. These results suggest that hyperinsulinemia and/or insulin resistance may not be involved in the development or maintenance of hypertension in SHR, which is in contrast to models of hypertension such as obese Zucker rats or fructose-fed rats.

Animals↗
PubMed1994

Inhibition by dexamethasone of retinoic acid-induced enhancement of leukotriene C4 synthesis in rat basophilic leukemia-1 cells.

We investigated inhibitory actions of dexamethasone (DEX) on retinoic acid (RA)-induced enhancement of leukotriene C4 (LTC4) synthesis in rat basophilic leukemia-1 (RBL-1) cells. Cultured cells were preincubated with RA for 16 h with or without DEX, and generation of LTC4 was measured by high performance liquid chromatography in cell-free and intact cell systems. RA (0.1 microgram/ml) significantly potentiated calcium ionophore-stimulated production of LTC4 synthesis. DEX inhibited the RA-induced enhancement of LTC4 synthesis by up to approximately 95% in intact cells when stimulated with calcium ionophore. RA-induced LTC4 synthase activity, which was determined by enzyme assay, was also inhibited by DEX by 65% in a cell-free system. This discrepancy of inhibition between the intact and cell-free systems was due to a partial inhibition of phospholipase A2 activity by DEX in the intact cells. These results indicate that the production of LTC4 is predominantly regulated at a level of LTC4 synthase. The induction of new LTC4 synthase activity by RA and inhibition of the RA-induced activity by DEX are important regulatory mechanisms of LTC4 synthesis.

Animals↗
PubMed1994

Accurate diagnosis of metastatic cardiac leiomyosarcoma with infundibular stenosis and cardiac tamponade by transesophageal echocardiography and Gd-DTPA magnetic resonance imaging--report of a case.

We present a patient with metastatic cardiac leiomyosarcoma that was diagnosed antemortem by transesophageal echocardiography (TEE) and ECG-gated magnetic resonance imaging with gadolinium diethylene triaminepentaacetic acid (Gd-DTPA MRI). TEE and Gd-DTPA MRI clearly revealed the morphological characteristics of infundibular stenosis and cardiac tamponade. Our patient has survived about 30 months after cardiac surgery. Since sarcoma is usually associated with a very poor prognosis, surgical treatment should be performed as soon as possible. TEE with color Doppler imaging and Gd-DTPA MRI are very useful diagnostic methods for determining the precise anatomical characterization of cardiac tumor, and these procedures are prerequisite to precise therapy.

Adult↗
PubMed1994

[A study on stressful life events of workers in Japan].

The experience rates of eighteen life events of Japanese workers were surveyed and the strength of each of the events was evaluated by a self-reported questionnaire. The fifteen professions surveyed included construction, transport, mailing, chemical production, banking, newspaper, TV services, commercial publishing, advertising, teaching and civil service. The number of workers who answered was 18,657 males and 4,443 females, aged 20 to 59 years. The male workers were divided and analysed in six job groups: clerical workers (n = 5,866), professionals (n = 3,696), blue collar day workers (n = 1,623), blue collar night or shift workers (n = 3,191), drivers (n = 1,663) and construction workers (n = 2,466). They were divided into groups and compared according to job, sex and five different age groups. The highest experience rate in each of the life events such as family trouble for both sexes, death of a family member, financial trouble and anxiety, death of a close friend, dissatisfactory transport to workplace or job, respectively. Comparing the experience rates between males and females we found no significant difference for five items. However, other items had higher experience rates for males than for females with the exception of family trouble. In regard to the age characteristics of each of the life events, as the age increased the experience rates of health-related life events such as the death of a spouse, child, family member or close friend and one's own illness or injury became higher. In contrast, the experience rates of items such as moving to a worse residence and failure in a school or training program became lower as the age increased for both sexes. Among job groups, construction workers had the highest experience rates of most life events except for the item of dissatisfactory transport to the workplace or job. Among other job groups, drivers had higher experience rates in the following four items: re-employment, death of spouse, divorce and financial trouble and anxiety. Blue collar day workers had higher rates for failure in school or training program and family trouble. The blue collar night or shift workers had higher rates for failure in school or training program and dissatisfactory transport to the workplace or job. The mean values of strength in six life events: re-employment, death of a family member, death of a close friend, serious physical illness, dissatisfactory transport to the workplace or job and family trouble were stronger in females than in males.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1994

Scanning electron microscopical observation of the intramitochondrial body in the bovine corpus luteum during pregnancy and after parturition.

Large luteal cells of the bovine pregnant luteum can be characterized as steroid-producing cells. Mitochondria of these cells contained intramitochondrial bodies (IMB). The three-dimensional structure of the IMB and the degenerative process of luteal cells were as follows: 1) The IMBs were globular or oval, 0.1 to 1.5 microns in diameter. Their outer surfaces were coarse but their cut surfaces were uniform. Their outer surfaces changed from rough to smooth during pregnancy. 2) At the late stage of pregnancy, the large luteal cells lost their cytoplasmic processes, showing the first sign of degeneration at the cell level in such a way that their mitochondrial cristae transformed from tubular to laminar, and that they contained accumulated lipid droplets. 3) After parturition, the IMBs came out from degenerating large luteal cells, and were conveyed by lymphatic capillaries.

Animals↗
PubMed1994

Dentin hypersensitivity. Occlusion of dentinal tubules by brushing with and without an abrasive dentifrice.

Daily toothbrushing with and without an abrasive dentifrice was performed on the ground surfaces of human cervical dentin attached to resin plates, which had been exposed to the oral cavities of 4 subjects for 8 weeks. Brushing with a dentifrice containing calcium hydrogen phosphate as an abrasive caused most of the dentinal tubules to open. The patency of dentinal tubules is thought to induce dentin hypersensitivity. Brushing without a dentifrice, on the other hand, resulted in occlusion of the dentinal tubules with organic pellicle-containing minerals. Furthermore, abrasion did not occur; however, no bacterial plaque or dental calculus were retained. The occluded tubules which were distributed over the entire dentin surfaces will likely prevent hypersensitivity. Such organic-mineral materials occluding the tubules can be derived from saliva and embedded by the brushing. We suggest that use of a non-abrasive dentifrice will prevent or reduce dentin hypersensitivity in the cervical regions.

Adult↗
PubMed1994

Familial arteriovenous malformations of the brain--two case reports.

Familial arteriovenous malformation (AVM) of the brain is an uncommon entity. A 24-year-old female presented with sudden onset of left hemiparesis due to an AVM with a hematoma in the right frontal lobe, which was surgically removed. Her 23-year-old younger sister presented with motor aphasia and right hemiparesis due to an AVM with a hematoma in the left frontoparietal lobes, which was surgically removed. Thirty-two patients in 15 families have been described in total. The mean age of these patients was 28 years, with 15 males and 17 females. Multiple AVMs occurred in four patients (12.5%), more frequently than in non-familial cases.

Adult↗
PubMed1994

Changes in nitrogen balance with age in calves weaned at 5 or 6 weeks of age.

Three experiments were conducted to examine the changes of N utilization after early weaning in calves. In Exp. 1, eight male Holstein calves were weaned at 5 wk of age and N balance was determined on the 1st, 6th, 11th, and 19th wk after weaning. In Exp. 2, to examine the effect of weaning age on N utilization, three calves were weaned at 5 wk of age and the other three at 11 wk of age. The N balance of both groups was determined on the same weeks of age (i.e., the 1st, 6th, 8th, and 11th wk after weaning in the earlier-weaned group). In Exp. 3, to examine the effect of a higher content of CP (17.9%) and TDN (75%) in concentrate on N utilization, three calves were weaned at 6 wk of age and the N balance was determined on the 1st, 5th, 10th, and 20th wk after weaning. The intake of concentrate was low in wk 1 but rapidly increased in the next 5 wk (1.74 and 1.72 times in Exp. 1 and 2, respectively). Nevertheless, the TDN intake tended to be lower in calves weaned early just after weaning compared with that in suckling calves in Exp. 2. The apparent N digestibility steadily increased with age and reached a plateau on wk 11 and 6 after weaning in Exp. 1 and 2, respectively. Conversely, the ratio of N retained:N absorbed tended to be high up to wk 6 after weaning and thereafter decreased, leading to a transient high N retained:N intake ratio on wk 6 after weaning.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗