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T Miwa

Publications and source records attributed to T Miwa.

At least 271 records · Page 15Linked to original sources

Muramyl dipeptide-elicited production of PGD2 from astrocytes in culture.

We used primary cultures of rat brain astroglial cells in order to investigate the interrelationship between PGD2 and other sleep-promoting substances such as muramyl dipeptide (MDP), lipopolysaccharide (LPS), delta-sleep-inducing peptide (DSIP), uridine, and interleukin 1 (IL-1). A large amount of PGD2 was released into the culture medium by stimulation with MDP, LPS, and IL-1 but DSIP and uridine failed to stimulate such release. These results suggest that PGD2 may be part of the series of biochemical steps involved in induction of sleep by MDP, LPS, and IL-1.

Acetylmuramyl-Alanyl-Isoglutamine↗

Detection of proliferative cells in dysplasia, carcinoma in situ, and invasive carcinoma of the uterine cervix by monoclonal antibody against DNA polymerase alpha.

The distribution of DNA polymerase alpha-positive cells in neoplasia of the uterine cervix and in normal cervical epithelium was studied using a monoclonal antibody against DNA polymerase alpha. The positive cells were found only in the parabasal layer of normal cervical epithelium and only in the nonkeratinized areas of the cancer nests of invasive keratinizing carcinoma. Most cells in cancer nests of an invasive nonkeratinizing carcinoma were found to be DNA polymerase alpha-positive. In cases of mild or moderate dysplasia DNA polymerase alpha-positive cells were found only in the lower half of the epithelium. DNA polymerase alpha-positive cells in severe dysplasia to carcinoma in situ were distributed throughout the full thickness of the epithelium. The percentages of DNA polymerase alpha-positive cells in mild or moderate dysplasia, severe dysplasia to carcinoma in situ, and invasive carcinoma were 32.2%, 45.7%, and 53.7%, respectively. The authors previously developed immunohistochemical methods for detecting DNA polymerase alpha by monoclonal antibody that allowed the proliferative activity of cells in normal and neoplastic tissues to be estimated.

Antibodies, Monoclonal↗

The effect of omeprazole on ultrastructural changes in gastric parietal cells.

This study was designed to compare the effects of omeprazole and cimetidine on ultrastructural changes in parietal cells of guinea pigs during histamine stimulation. Both omeprazole and cimetidine remarkably inhibited acid secretion induced by histamine stimulation. Omeprazole, however, failed to prevent the morphological transition of parietal cells to an active stage during histamine stimulation, in contrast to cimetidine which inhibited the morphological transition. In addition, it was noticed that administration of omeprazole caused vacuolation in approximately 27% of all parietal cells. This phenomenon was not seen in control animals with histamine stimulation alone and only very rarely in cimetidine treated animals. Ultrastructural findings suggested that vacuoles originated in secretory canaliculi of parietal cells. These results may be the key to explain the difference of the inhibitory mechanism between omeprazole which acts on the final step of intracellular process (so-called proton pump) and cimetidine which acts on the H2-receptor site of plasma membrane.

Animals↗

Significance of intravenous olfaction test using thiamine propyldisulfide (Alinamin) in olfactometry.

The significance of intravenous olfaction test in olfactometry was studied by injection of thiamine propyldisulfide (Alinamin) intravenously. An original solution of Alinamin is a thiol-type derivative of vitamin B1, and releases a mercaptan smell (garlic smell) in expired air when it arrives at the olfactory epithelium via the nasopharynx. In the intravenous olfaction test (Alinamin test), the latent time which is a period between the initiation of injection and recognition of garlic smell, and duration time which is a period between the recognition and disappearance of smell are measured. Our results indicated that latent time is influenced by olfactory acuity and duration time depends on olfactory adaptation phenomenon. Central olfactory disorders were highly suspected in hyposmia patients with duration time of less than 15 sec, and nonresponders in Alinamin test always showed poor prognosis in the recovery of olfactory acuity. It was considered that the Alinamin test is useful not only for estimating the degree of olfactory disorders, but also for differential diagnosis of impaired lesions and olfactory prognosis.

Chronic Disease↗

Importance of unilateral examination in olfactometry.

Hyposmia, the decreased sense of smell, and anosmia, the loss of sense of smell, may be unilateral or bilateral. If the olfactory acuity examined by means of bilateral test is normal, olfactory disorders are not found; unilateral examination is therefore necessary for definite evaluation of olfactory acuity. As evidence, 7 cases out of 94 patients with chronic rhinosinusitis and 6 cases out of 12 patients who received the surgery of anterior cranial fossa showed definite different olfactory threshold between nasal cavities, and there were no patients who recognized the diminished sense of smell in spite of unilateral high olfactory threshold. Additionally, we have experienced that a patient with brain tumor was diagnosed by the help of unilateral olfactory test. We thus strongly recommend the unilateral olfactometry as a method for simple and reliable test in clinical measurement of the sense of smell.

Chronic Disease↗

Usefulness of word table for the quantitative evaluation of the recognition threshold in children's olfactometry.

In the quantitative evaluation of the recognition threshold in smell test, the influences of subjects' age, intelligence, and experience are unavoidable in expressing the nature of smell, especially in children. In order to avoid such individual differences, a word table has been designed in our clinic. In this study, we employed a word table for children's quantitative evaluation of the recognition threshold, and found that T & T olfactometry performed with use of a word table showed a greater reliability compared to the test without use of a word table. The use of a word table for children's olfactometry is also considered to be an easily administered procedure.

Adult↗

Gastric metaplasia in duodenal ulcer. Histochemical considerations of its pathophysiological significance.

Gastric metaplasia of the duodenal mucosa in biopsy specimens of healed duodenal ulcer and in surgical specimens of perforated duodenal ulcer was investigated using mucin histochemistry and the indirect immunoperoxidase method. Endoscopic methylene blue test was performed prior to biopsy. All specimens from areas showing no dye absorption revealed varying degrees of gastric metaplasia characterized by heterotopic occurrence of gastric-type foveolar cells mainly at the tips of stunted intestinal villi. On average, 31.8% of the total surface length of duodenal mucosa taken from areas showing no dye absorption was occupied by the metaplastic cells. They showed strong reactivities for periodic acid-Schiff (PAS) and galactose oxidase-Schiff sequences, while alcian blue and paradoxical concanavalin A staining, class III, were negative. Immunoperoxidase-PAS double staining revealed a few gastrin and somatostatin cells in foci of gastric metaplasia, but almost no cells containing motilin, secretin, cholecystokinin and gastric inhibitory peptide. Such endocrine cells were scattered in nonmetaplastic mucosa. While such metaplastic change has been regarded as a self-defence mechanism or adaptation of the duodenal mucosa against acid, a local decrease of normal endocrine cells, which allegedly function as acid receptors, may lead to alterations of gastroduodenal interaction. It is suggested that gastric metaplasia is important as one of the pathophysiological mechanisms involved in the recurrence of duodenal ulcer.

Adult↗

Evaluation of vertical vibration given to the human foot.

The effects of acceleration amplitudes and frequencies of vertical foot vibration on mechanical and sensation responses were studied in two sets of experiments. The first experiments determined the mechanical characteristics of the foot in three seated subjects at frequencies between 5 and 1000 Hz, in terms of the driving point mechanical impedances and acceleration transmission ratios between the foot and lower leg. In the second set of experiments, sensation scales for foot vibrations were determined in ten seated subjects at octave center frequencies between 8 and 400 Hz, which involved equal sensations of continuous and impulsive motions, sensation magnitudes, and rating of five successive categories of sinusoidal motion. Contours of mechanical and sensational responses are presented. Using the results obtained, a foot response meter was made and used in a field survey to evaluate foot vibration.

Acceleration↗

Interaction of nuclear proteins with muscle-specific regulatory sequences of the human cardiac alpha-actin promoter.

The human cardiac alpha-actin promoter is involved in the muscle-specific transcriptional regulation of the gene. In this study, we utilized gel mobility shift, methylation interference, and DNase I protection assays to examine protein factor interaction with the promoter in vitro. All assays demonstrated specific interaction of nuclear factors with a region of the promoter encompassed by nucleotides -93 to -113 base pairs from the transcriptional start site. This region contains a CC(A + T-rich)6GG element, termed a CArG box, which has previously been implicated in the muscle-specific transcriptional regulation of the gene by functional assays. Although the gene is only expressed in muscle cells, identical binding activity was present in nuclear extracts of all cell types examined, including those of muscle (C2, L8, and L6 cells) and nonmuscle (HeLa, NIH 3T3, HuT12, and L cells) origin. Furthermore, methylation interference assays showed that identical nucleotides interacted with factors isolated from C2 and HeLa cells. Competition studies showed that the CArG-binding factor, designated as CBF, also interacts with the c-fos serum responsive element, which contains a CArG element, but not with the simian virus 40 enhancer and early promoter. Thus, a region of the human cardiac alpha-actin promoter known to be functionally involved in muscle-specific regulation of the gene appears to interact in vitro, and in an identical manner, with a factor(s) which is neither muscle nor gene specific, suggesting a more complex mode of regulation than previously envisioned.

Actins↗

Prenatal protein-energy malnutrition alters various biochemical components of the membranous bones in fetal rats.

The effects of prenatal protein-energy malnutrition on the biochemical parameters of the membranous bone were studied using fetal rats. Timed pregnant rats were fed a protein-deficient diet as an experimental group from day 13 of gestation, whereas control dams were fed a normal protein diet. By day 15, radioactive Na2SO4 was injected. On day 22, all fetuses were delivered by cesarean section. The hexosamine content per milligram dry tissue, and the protein and hexosamine contents per guanidine-HCl extract were greater in the mandibles but less in the calvaria of the malnourished group than in those of the controls. Calcium content per gram dry tissue was lower in both bones of the malnourished group. 35S-sulfate uptake per milligram dry tissue or milligram proteoglycan was greater in the malnourished group than in the controls in both bones. The mandible in the malnourished group had less lower-weight molecular proteoglycan subunits in the dissociative condition. Protein-energy malnutrition affects the mandible and calvaria in different ways, although both bones originate from membranous bone. Insufficient degradation of proteoglycan could be the reason for the delay of mineralization in the malnourished bones.

Animals↗

A case of spontaneous esophageal rupture treated with conservative therapy.

A 51 year-old male was admitted because of abrupt hematemesis and loss of consciousness. Emergency endoscopy depicted a giant esophageal ulcer on the left side extending from the middle intrathoracic region to the lower intrathoracic region. Esophagography, performed on the second day of admission, revealed a huge cavity (10 cm x 7 cm) filled with contrast medium resulting from a rupture in the ulceration. His state of shock improved with conservative therapy and no severe mediastinitis was noted. The drainage from the cavity into the lumen of the esophagus was considered to be acceptable from esophagography and an endoscopic examination. Secondary to his stable condition and continuous drainage, this patient was treated conservatively throughout his clinical course. The patient was given intravenous hyperalimentation (IVH) until the 25th hospital day and was medicated with broad spectrum-antibiotics. On the 21st hospital day the size of the esophageal cavity was markedly decreased (7 cm x 2 cm). Only small irregular mucosa was noted on the esophagogram taken 6 weeks after admission. Six months after the onset, an X-ray examination revealed complete healing of the spontaneous esophageal rupture with no recurrence.

Anti-Bacterial Agents↗

Activity and distribution of histidine decarboxylase and histamine concentration in rat stomach.

The involvement of histamine in mediating gastric function under normal and pathological conditions has been largely established. Histidine decarboxylase (HDC) is the only synthetic enzyme of histamine in the mast cell or enterochromaffin like (ECL) cell. In this study, we examined, the activity of HDC by a method based on the modification of Kobayashi's method, the histological distribution of HDC containing cells was determined by an immunohistochemical method and the histamine concentration by a HPLC method in rat stomach. Histamine concentration in the total gastric layer of the fundus is overwhelming large compared to that in the antrum. On the other hand, histamine concentration of the mucosal layer of the fundus is 72.1 +/- 0.4 micrograms/g (mean +/- S.D.) and that in both the muscular and serosal layers is 7.2 +/- 0.4 micrograms/g. HDC activity of the total gastric layer of the fundus was about ten times as high as that in the antrum. Histological distribution of HDC-containing endocrine cells was observed in the basal part of the gastric mucosa of the fundus, but could not be observed in the muscular and serosal layer. These results suggest that HDC-containing endocrine cells, in only the basal parts of the mucosal layer of the fundus, were similar to ECL cells and have important parts for biosynthesis of internal gastric histamine. Therefore, using the total gastric layer of the stomach was thought to be easier than using only the mucosal layer for measuring gastric histamine and HDC-activity in rats.

Animals↗