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Biomedical subjects

I Watanabe

Publications and source records attributed to I Watanabe.

At least 793 records · Page 44Linked to original sources
PubMedDate not supplied

Expression of stem cell factor in pterygium.

PURPOSE: To investigate the possible role of stem cell factor (SCF) in the pathogenesis of pterygium. METHODS: The localization of SCF was examined immunohistochemically in excised tissue from 4 primary pterygia and 5 normal conjunctival specimens. RESULTS: Three of the four pterygia showed strong immunoreactivity of SCF in the subepithelial connective tissue at the cap area. This immunoreactivity was completely blocked by using a primary antibody preincubated with recombinant SCF. The SCF-positive cells were identified as a population of fibroblasts by immunostaining for vimentin and prolyl 4-hydroxylase in adjacent sections. No apparent immunoreactivity of SCF was observed in the subepithelial connective tissues in the head and body of the pterygia and in the normal conjunctiva. CONCLUSION: Stem cell factor is overexpressed in fibroblasts at the cap area of most pterygia.

Antibodies, Monoclonal↗
PubMedDate not supplied

Postnatal transfer of PCBs from exposed mothers to their babies: influence of breast-feeding.

Polychlorinated biphenyl (PCB) concentrations in the blood of mothers who were occupationally exposed to PCBs in a capacitor manufacturing facility, and their children, were analyzed from 1975 to 1979. The factory terminated PCB use in 1972, and environmental PCBs were eliminated artificially. Despite this, blood PCB levels of the mothers were very high, i.e., 10-100 times higher than that of non-occupationally exposed persons. In a previous report, we discussed the relationship between breast-feeding and PCB levels in the blood. This relationship is confirmed further by the present investigation which continued during a 5-yr period. The PCB levels in blood of children were influenced greatly by the duration of breast-feeding, but showed little relationship to the PCB levels in maternal blood. The PCB exposure period of the mothers, time of birth, and age of the children were less clearly related to the PCB levels in the children. The PCB concentration in the children's blood decreased at a constant rate and was independent of their blood PCB levels. A similar result was noted for their mothers' PCB levels. A slight difference, however, was found in the rate of decrease of blood PCB levels between the mothers and children. The results of questionnaire research on the health conditions and the medical examinations for the children showed that frequency of complaints, e.g., red eye, fever, itchy skin, and carious teeth, related favorably to the duration of breast-feeding. Less severe findings, i.e., decay of nails, pigmentation, mottled enamel, carious teeth, which were typical symptoms in yusho patients, were observed in some children. They were not, however, diagnosed as having PCB poisoning inasmuch as medical treatments were unnecessary.

Breast Feeding↗
PubMedDate not supplied

Early edematous lesion of pyrithiamine induced acute thiamine deficient encephalopathy in the mouse.

Pyrithiamine induced acute thiamine deficient encephalopathy in the mouse is one of the possible animal models of human Wernicke-Korsakoff syndrome. In this experiment, the adult male Swiss Mice, treated with a daily subcutaneous injection of pyrithiamine in conjunction with a thiamine deficient diet, abruptly developed unique encephalopathic signs on day 10. In the animals sacrificed immediately after the onset of the disease, the gross examination of the brains revealed a small number of minute hemorrhagic lesions in the thalamus, mammilary bodies and pontine tegmentum, including the medial and lateral vestibular nuclei. When spared the hemorrhage, these regions appear intact grossly and in paraffin sections, but were found to be significantly altered in Epon sections. In semithin Epon sections of the pontine tegmentum, there was edematous swelling of all the astrocytes and oligodendrocytes and occasional myelin sheaths. By electron microscopy, the edema of astrocytes involved both nucleus and cytoplasm extensively. The oligodendroglial edema was severe in the peripheral cytoplasm, particularly in the inner loops of the myelin sheaths and only moderately in the nuclei, perinuclear cytoplasm and outer loops. Disintegration of the myelin lamellae occurred when edema of the inner loops had advanced. The axis cylinders surrounded by the edematous loops were essentially intact. In contrast to such glial cell damage, the nerve cells and blood vessels were not altered. These findings suggest that (1) astroglia and oligodendroglia are the cells most sensitive to thiamine deficiency and (2) the resultant glial cell injury is the initial change of thiamine deficient encephalopathy in man and in experimental animals.

Animals↗
PubMedDate not supplied

Evaluation of hyperactive caloric responses in patients with inner ear diseases.

Twenty-three patients with various types of inner ear diseases, who showed hyperactive caloric responses (21 patients showed unilateral hyperactive caloric responses, and 2 patients showed bilateral hyperactive caloric responses) were monitored during 2-10 years and underwent caloric tests repeatedly (2-7 times). None of them showed continuous hyperactivity of the labyrinth throughout their clinical courses. It seems that hyperactive caloric responses in patients who suffer from inner ear disease may be a transient phenomenon, caused by fluctuations of the vestibular condition, central compensation, age and/or mental state of the patients.

Adult↗
PubMedDate not supplied

Characteristics of capillary permeability in nasal mucosa.

The transendothelial passage of horseradish peroxidase (HRP) and colloidal carbon and diffusion of HRP in pericapillary space, injected intravenously into rats, was studied at the light microscopic and ultrastructural level in the nasal mucosa. In the lamina propria of the mucosa in the middle third of the nasal septum of rats, the capillaries directly beneath the epithelium were mostly with fenestrae, while the capillaries around the nasal gland were without the fenestrae. The permeability of the capillaries in the lamina propria of the nasal mucosa was very high and some of the endothelial cells were wide open, like liver sinusoid, allowing free passage of carbon pasrticles. Marked transendothelial passage was also noted at ten seconds after HRP infusion through the capillaries without fenestrae located around the nasal gland. On the other hand, no extracapillary leakage of HRP was noted even at 150 seconds after its infusion in the capillaries without fenestrae located in the muscles. The permeability of small venules located in the lamina propria of nasal mucosa also was extremely high. The reasons for the greater permeation of HRP through capillaries of nasal mucosa are as follows. First, the endothelial cell junction was loose in the nasal mucosa and in some capillaries endothelium had holes like liver sinusoid. Second, interstitium surrounding the capillary was loose in nasal mucosa.

Animals↗
PubMedDate not supplied

Morphological alterations affecting the microvasculature in nasal allergy.

The fine structure of human nasal blood vessels was studied in 15 nasal allergic patients. Biopsies were taken at different stages after provocation. In the early stage (two minutes after provocation), characteristic alterations of capillaries and venules were congestion, gap formation between two endothelial cells, and swollen vascular endothelial cells. Evidence of locally increased vascular permeability and congestion causing mucosal edema was found. In the late stage (20 minutes after provocation), evidence of congestion disappeared. Vascular dilatation and marked interendothelial cell gaps were observed. In both perivascular space and sometimes in intravascular space, degranulated eosinophils were observed, suggesting that not only histamine but also lysosomal enzymes in eosinphil granules may be involved in causing increased vascular permeability.

Adolescent↗
PubMedDate not supplied

Reaction mechanism of protocatechuate 3,4-dioxygenase.

We have observed that high SOD-like function (decomposition of superoxide anion) was observed for several iron(III) compounds with tripodal ligands and several oxovanadium(IV) compounds, and also that these compounds exhibit high catalytic activity for oxidative cleavage of 3,5-di-tert-butylcatechol in non-donating solvents such as dichloromethane or nitromethane. These are suggesting that the same reaction intermediate exists in reaction mixtures of both the SOD-like and catecholase-like functions of these compounds. Based on these facts, we have proposed a new reaction mechanism for the oxidative cleavage of catechol catalyzed by the native non-heme iron dioxygenases; this includes formation of an iron(III)-peroxide adduct as a reaction intermediate, which exhibits electrophilic nature.

Binding Sites↗
PubMedDate not supplied

Meniere's disease and the mastoid pneumatization.

The size of the mastoid penumatization was radiographically examined and planimetrically measured in the patients with Meniere's disease, patients with other sensorineural hearing loss and clinically ear healthy persons. Law projection was used for the radiographical examination. No statistical differences were seen among the three groups. Meniere's disease and the factors which influence the mastoid pneumatization are discussed.

Adult↗
PubMedDate not supplied

Transfer of radioisotope from CSF to nasal secretion.

The physiological range of radioisotope (RI) transferred from the CSF to the nasal secretions was observed in 17 subjects without CSF rhinorrhea. A combination of RI cisternography and insertion of cotton pledgets in the nose was used in order to detect the RI transfer in the nasal secretion. The RI ratio was calculated, and those of the 17 subjects were less than 0.3. This is likely to be the normal physiological range of RI transfer.

Adult↗
PubMedDate not supplied

Communicatory routes connecting the middle ear, the inner ear and the subarachnoid space via perineural space.

Twenty-one rabbits received injection of Indian ink into the stylomastoid foramen. Observation of the serial sections of their temporal bones revealed Indian ink infiltration into the subarachnoid space, along the facial nerve, the auricular branch of the vagus nerve and the tympanic nerve. Along the acoustic nerve, the infiltration was found as far as the fundus of the internal auditory meatus. In some cases, however, Indian ink reached the subarachnoid space and infiltrated into the scala tympani, scala vestibuli and around the saccule by way of the cochlear aqueduct. These routes are suspected to be a course of spreading infection or tumor cells.

Animals↗
PubMedDate not supplied

Effects of exercise on nasal resistance and nasal blood flow.

Nasal resistance and nasal blood flow were measured consecutively before exercise, immediately after exercise, 5, 10, 15, 20, 25, and 30 minutes after exercise in 11 normal subjects and 18 patients with perennial allergic rhinitis. Nasal resistance was measured by Nihon-Koden Rhinorheograph MRP 2100, and nasal blood flow was measured by Periflux PF2, a laser doppler flowmeter. 77% of unilateral nasal cavities in normal subjects and 75% of unilateral cavities in patients with allergic rhinitis showed a decrease of both nasal resistance and nasal blood flow immediately after exercise. However, rates of changes in nasal resistance and in nasal blood flow were not correlated with each other. In the latter period after exercise, there was a discrepancy between nasal resistance and nasal blood flow. A laser doppler flowmeter is considered to measure blood flow in the superficial part of the nasal mucosa. Based upon our results, an intensive stimulus such as exercise seems to induce vasoconstriction in the superficial part as well as in the deeper part of the nasal mucosa. However, it is also suggested that the vessels in the various parts of the nasal mucosa don't always respond in the same way.

Adolescent↗
PubMedDate not supplied

Nasal resistance and nasal blood flow in postural changes.

Posture greatly influences nasal resistance. To investigate whether nasal blood flow synchronizes with nasal resistance during changes in posture, correlation coefficients were calculated based on findings from both nasal cavities in 14 normal subjects. There was no correlation between nasal resistance and nasal blood flow, except in the left nasal cavity of one subject. Nasal blood flow was measured by a laser Doppler flowmeter, which detects the blood flow in the superficial part of the nasal mucosa. Nasal resistance is regulated mainly by capacitance vessels located in the deeper part of the nasal mucosa. Therefore, the dissociation in nasal resistance and blood flow responses to postural changes noted in our study suggests that vessels in different parts of the nasal mucosa respond differently to this same stimulus.

Adult↗
PubMedDate not supplied

Blood pressure and cochlear blood flow in the guinea pig.

The relationship between blood pressure and cochlear blood flow was investigated in 68 guinea pigs, using the vasoactive drugs angiotensin II, norepinephrine, phentolamine, isoproterenol, dobutamine, salbutamol, propranolol, bradykinin, papaverine, vinpocetine dilazep, and brovincamine. Cochlear blood flow increases markedly and proportionately to increases in blood pressure. By contrast, cochlear blood flow shows various responses toward a fall in blood pressure. In general, cochlear blood flow appears relatively resistant to blood pressure decrease.

Animals↗
PubMedDate not supplied

A field emission SEM and HVTEM study of collagen fiber bundles in the lamina propria of the palatine mucosa in the developing mouse.

The ultrastructural development of the surface belonging to the epithelium-connective tissue interface of the hard and soft palatine mucosa of mouse was studied using field emission scanning electron microscopy and high voltage transmission electron microscopy methods. The tissues were analysed at 18 days of gestation, and, 1, 3, 7, 14, 21, 30 and 90 days after birth. The three-dimensional architecture of the connective tissue in the lamina propria showed different shapes. The papillae began to form on days 7 and 14 but continued to growth until the adult period. Different stages of primary and secondary connective tissue papillae were recognized in the hard palatine mucosa whereas the soft palate showed erect connective tissue papillae, small round formations containing taste buds and several openings of the salivary glands ducts.

Aging↗