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Biomedical subjects

N Okita

Publications and source records attributed to N Okita.

18 recordsLinked to original sources
PubMed1991

In vitro cytotoxicity of tissue conditioners.

The cytotoxicity of four commercial tissue conditioners was evaluated by the agar overlay method. Every material either fresh or stored for 1 hour, 24 hours, 8 days, or 15 days, showed some degree of cytotoxicity. Coe Comfort and Kerr FITT materials exhibited marked cytolysis, whereas GC Soft-Liner and Visco-gel materials caused a decolorized zone with minimal cell damage. Based on the sum of reaction indices, the tissue conditioners tested seemed to be more cytotoxic than autopolymerizing denture base resins. Further analyses are needed to identify the cytotoxic components that continued to leach out from the tissue conditioners for at least 15 days.

Acrylic Resins↗
PubMed1991

Paroxysmal speech disorder following left frontal brain damage.

The patient was a 61-year-old female who suffered from the sudden attack of a speech disorder. The episodes of speech disorder lasted for less than 1 min, but occurred several times a day, paroxysmally. A CT revealed a low density area on the surface of the left frontal lobe and an EEG showed an abnormal wave at the frontoparietal area, more dominantly on the left. This condition was diagnosed as a kind of epilepsy. The paroxysmal speech disorder occurred very often during the 2 months after the first episode. However, with therapy using anticonvulsives and antibiotics, the condition began to improve after 4 months and disappeared completely after 6 months. It is assumed that the inflammatory change which occurred at the frontal lobe stimulated the supplementary motor area paroxysmally, and subsequently the speech disorder occurred as a kind of epilepsy.

Brain Damage, Chronic↗
PubMed1991

In vivo and in vitro studies on soft denture materials: microbial adhesion and tests for antibacterial activity.

The microbiological properties of four tissue conditioners, one soft liner, and one acrylic resin were studied. The tissue conditioners showed no or negligible antimicrobial effects toward salivary microorganisms by two different in vitro tests. In in vitro adhesion experiments, more Streptococcus mutans and Candida albicans adhered to the tissue conditioners and the soft liner in comparison with conventional acrylic resin used for denture-base fabrication. No difference in bacterial adhesion was found among the tissue conditioners. The microbial colonization of two tissue conditioners lined on maxillary dentures in three volunteers was followed for 14 days. No difference among the materials was found, but a tendency for subject-dependence in plaque formation on the materials was noted.

Acrylic Resins↗
PubMed1991

Selective hypoaldosteronism in a patient with Sjögren's syndrome: insensitivity to angiotensin II.

A 51-year-old Japanese woman with hypokalemia due to distal renal tubular acidosis associated with Sjögren's syndrome exhibited a decreased plasma aldosterone level despite elevated plasma renin activity. Our studies revealed selective hypoaldosteronism with normal adrenoglucocorticoid function. In the presence of a low level of serum potassium (3.6 mEq/l), plasma levels of deoxycorticosterone and corticosterone were normal, while plasma aldosterone was very low. The levels of these three mineralocorticoids showed only minor changes during infusion of angiotensin II. Furosemide administration under almost the same level of serum potassium (3.7 mEq/l) resulted in only a slight increase of plasma aldosterone. Since hypokalemia might possibly suppress the synthesis of aldosterone in the zona glomerulosa, angiotensin II was also infused under a normal level of potassium (4.3 mEq/l). However, angiotensin II also failed to stimulate any secretion of aldosterone, despite a progressive rise in blood pressure and sufficient suppression of plasma renin activity. On the other hand, rapid ACTH administration in the presence of 4.4 mEq/l of serum potassium increased both plasma aldosterone and cortisol. These results suggest that adrenal insensitivity to angiotensin II was the cause of the selective hypoaldosteronism in our patient, possibly due to a dysfunction of adrenal angiotensin II receptors, a disorder of postreceptors or both.

Acidosis, Renal Tubular↗
PubMed1987

Paroxysmal kinesigenic choreoathetosis and paroxysmal dystonic choreoathetosis in a patient with familial idiopathic hypoparathyroidism.

A patient with familial idiopathic hypoparathyroidism whose major symptoms were paroxysmal kinesigenic choreoathetosis (PKC) and paroxysmal dystonic choreoathetosis (PDC) was reported. CT revealed marked calcification in the basal ganglia, the thalamus and the dentate nucleus of cerebellum. Positron emission tomographic (PET) study showed decreased glucose metabolism in the basal ganglia and thalamus. The paroxysms were eliminated by the normalization of serum calcium level. Thus the paroxysms seemed to be induced by hypocalcemia which stimulated the lesions in the basal ganglia and thalamus, on one occasion, as in PKC, and on the other occasion, as in PDC. Concomitant occurrence of both PKC and PDC in a patient is unique and is of interest in considering the pathomechanisms of these different but related disorders.

Adult↗
PubMed1987

Comparative studies on clinical features and CSF proteins of motor neuron disease patients.

Clinical features such as types of diseases, sex ratio, age of onset, sites of initial involvement, the appearance of bulbar signs, and duration of illness were studied in 52 patients with motor neuron disease (MND) with a special reference to immunoglobulin in cerebrospinal fluid (CSF) and serum. Although MND has been thought to be a degenerative disease of unknown cause, our data suggested there are some immunological abnormalities in this disease. The duration of illness and the abnormalities of CSF immunoglobulins appeared to be correlated with the type of disease and the site of initial involvement. However, whether or not these abnormalities in CSF immunoglobulins are directly related to the pathogenesis of MND remains unclear.

Adult↗
PubMed1987

Endocrinological abnormalities in myotonic dystrophy: consecutive studies of eight tolerance tests in 26 patients.

We studied endocrine functions of the hypothalamus, pituitary, thyroid, gonad, adrenal and pancreas in 26 patients with myotonic dystrophy. The following findings were obtained: (1) Hyporesponsivenesses of HGH to insulin, arginine and L-dopa test were observed in 25%, 45% and 54.5% of patients, respectively. To the administration of sulpiride and TRH, hypo- or hyperresponses of plasma PRL were observed in 4 or 2 patients, respectively. (2) Depressed plasma levels of testosterone were observed in 4 patients and those of estradiol were observed in 3 patients. Among these 7 patients, five were hypergonadotropic and the remaining two were hypogonadotropic. From the data of plasma cortisol and urinary 17-OHCS, the adrenal functions in patients with myotonic dystrophy were considered to be normal. The renin-angiotensin-aldosterone systems in these patients were considered to be grossly normal. (3) Basal levels of T3, T4 and free T4 were within the normal ranges, but 6 of 19 patients showed low levels of 131I-uptake and 11 of 24 patients showed reduced BMR values. (4) The basal level of plasma insulin was elevated in 5 patients. Insulin responses to oral glucose were exaggerated and delayed in 21 of 26 patients. From these results and the statistical evaluation of each laboratory and clinical data, we concluded that 1) the degrees of disturbances of endocrine functions are at random in each patient. 2) The measures of intellectual function obtained by WAIS were directly correlated with basal levels of TSH, but inversely with basal levels of somatostatin. No specific correlation was found between endocrinological disturbances and neurological severities. 3) Impairment of some endocrine functions, such as the gonadal, thyroid and somatotroph functions, was closely correlated with age and the duration of disease.

Adolescent↗
PubMed1985

Sudden death during ambulatory monitoring in a patient with left main coronary artery disease.

A 61 year old male with left main coronary artery disease died suddenly during ambulatory Holter monitoring. The monitoring documented ST depression followed by ST elevation, followed by junctional and ventricular escape rhythms with no measurable blood pressure by cuff methods. The mechanism of sudden death in patients with left main coronary artery disease is thought to be a combination of ventricular fibrillation or bradyarrhythmia and electromechanical dissociation secondary to a sudden onset of severe pump failure.

Angiography↗
PubMed1985

[Quantitative measurement of ventricular dilatation on CT scan--a proposal of new index and review of literature].

CT scan is able to show cerebral atrophy more safely and more easily than pneumo-encephalography or cerebral angiography. Then, various methods have been reported for quantitative analysis of cerebral atrophy on CT scan. Generally, cerebral atrophy might be judged from the ventricular dilatation with some indices, calculated from various ventricular width. But, there is no general agreement on what index is the most reliable. In this paper, we attempted to establish the index, easy to measure and most reliable. Our method is as follow. Method. We carried out the CT scan (EMI 1010) on 89 neurologically intact patients. Scans were parallel to orbito-meatal line (OML), and were 10 mm in thickness. On CT scan films, various width, area of anterior horns and area of bodies of lateral ventricles were measured (Fig. 1). Measurement about the anterior horns of lateral ventricles were carried out on image the most clearly showed the foramen of Monro. And measurements about the bodies of lateral ventricles were on image, 20 mm above the image of anterior horn. Correlations of various width and areas were calculated (Table 1). Then we proposed new indices with high correlations (over 0.9) with ventricular area; Anterior horn CVI (Cerebro-Ventricular Index) and Body CVI (Fig. 2, 3). Patients with myotonic dystrophy show cerebral atrophy. We carried out the CT scan (GE-CT/T 8800) on 17 myotonic dystrophy patients and 30 controls. Between the two groups, age and sex were almost matched (Fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗