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J Kagawa

Publications and source records attributed to J Kagawa.

At least 55 records · Page 3Linked to original sources
PubMed1992

[The mechanism of neutrophil-induced lung injury--autoregulation of superoxide generation in cells].

Neutrophils which are isolated in the lung adhere to endothelial cells due to chemotactic factors, and release various proteases, superoxide anions and prostanoids in inflammatory processes. However, this host defense mechanism can cause tissue damage. Excessive adherent neutrophils are not always derived from lung injury. We have previously reported that an increase in cell density in human neutrophils attenuates superoxide anion generation by cell to cell communication (autoregulation). Autoregulation of the protein kinase c stimulator, phorbol myristate acetate, and also of the cell membrane receptor stimulator, N-formyl-methionyl-leucyl-phenyl-alanine was observed. The autoregulation was not related to the presence of extracellular Ca2+ not to a change of [Ca2+]i induced by stimulants. These results suggest that neutrophils accumulated in the lung tissue have a built-in defense mechanism induced by membrane to membrane contact of neutrophils, which protects tissues from an excessive inflammatory response.

Homeostasis↗
PubMed1991

[Subjective symptoms and blood findings in painters exposed to organic solvents].

Subjective symptoms and blood findings were studied in 16 construction workers and 30 vehicle repairmen using organic solvent and compared to 30 workers who were not exposed to organic solvents. A statistically significant increase was observed in the prevalence of subjective symptoms, serum phospholipid, lipoprotein fraction and IgE in construction workers and vehicle repairmen. A statistically significant decrease in neutrophils function was observed in construction workers.

Adolescent↗
PubMed1991

Comparison of longitudinally and cross-sectionally determined age-related decline in spirometric measurements.

In order to compare the longitudinally and cross-sectionally determined annual decline of spirometric measurements, we measured spirograms from 326 male adults four times over five years. Acceptable results were obtained three times or more in 269 subjects aged 30 to 55 at the initial survey. Longitudinal annual changes in the height-squared proportional values of forced vital capacity (CFVC), forced expiratory volume in one second (CFEV1), and maximal expiratory flow at 50% and 25% of FVC (CVmax 50 and CVmax 25), was estimated by the model in which the effect of each individual's level was included as an explanatory variable. The cross-sectional annual change in those indices was determined by including the effect of each survey's level in the model. The longitudinal estimate of annual decline was significantly smaller than the cross-sectional estimate for all indices except CVmax 25. No evidence suggested that systemic error of measurement or a learning effect caused significant bias in the data. The discrepancy in the estimated annual changes seemed to be caused by the cohort effect in our subjects, since the cross-sectional analysis is primarily sensitive to harmful factors operating in the past. We concluded that the longitudinal data for individuals or groups should not be compared with any reference value based on a cross-sectional analysis.

Adult↗
PubMed1991

[Longitudinal analysis of a four-year follow up of pulmonary function development in children with a past history of asthma].

In order to longitudinally study the pulmonary function development of children with a history of asthma, we measured the flow-volume curves of 441 fourth-grade children in seven primary schools randomly selected from the Kashima district in Ibaraki prefecture in 1980, and again in 1982 and 1984. Levels and slopes of pulmonary function indices for individual children were calculated in 325 children who performed acceptable forced expiratory maneuvers at all of the three surveys. In FVC and FEV1, no significant difference of levels and slopes was observed between children with asthmatic history and control children. However, the level and slope of V25 of children with asthmatic history were significantly lower than those of control children (0.5 l/sec for the level, 0.08 l/sec for the slope) even when only those who did not suffer from wheezing attack during the follow-up period were concerned. These results suggested that the functional change of peripheral airways in children with asthmatic history did not recover within a couple of years even when they were in remission. Moreover, the functional differences between those two groups of children might become larger in early adolescence.

Asthma↗
PubMed1991

[Sulfuric acid submicron aerosols induce morphological changes in the central airways in the guinea pig].

We examined the airway injury of the guinea pig exposed to sulfuric acid submicron aerosols (1 mg/m3). The animals were exposed to filtered air (sham control) or to submicrometer-sized sulfuric acid aerosols for 4 hr/day, 6 days/week, with sacrifices after 4 hours, 3 days, 1, 2, and 4 weeks of acid exposure. Light and electron microscopic examinations revealed that epithelial injury such as disappearance of cilia in the central airways was observed and the severity of the injury increased with exposure duration. This experimental study shows that submicrometer particles of sulfuric acid induces significant alterations in the central airways and may be involved in the incidence of asthma attack.

Aerosols↗
PubMed1990

Change in the growth hormone (GH) response to GH-releasing factor (GRF) caused by exogenous GH in short children.

To determine whether exogenous GH induces feedback of GH release in children, growth hormone-releasing factor (GRP) tests were performed before and after 10-day GH administration. Sixteen non-obese short boys, aged 5-14 yr, with normal GH response to pharmacological tests were studied. Mean basal and peak serum GH levels in GRF tests before and after exogenous GH were not significantly different. The subjects were divided into two groups, A and B, according to the percent change in integrated areas under the GH curves in GRF tests (GH AUC) before and after 10-day GH administration. Group A consisted of 6 boys with decreased GH AUC and group B consisted of 10 boys with increased GH AUC. Mean peak GH in GRF tests and mean GH AUC were significantly higher before exogenous GH in group A than in group B. The boys in group A were all prepubertal, while 4 boys in group B had begun their early pubertal change. The mean age in group A (7.8 +/- 1.8 yr) was significantly lower than that of group B (11.9 +/- 2.4 yr). GH AUC before exogenous GH showed a significant correlation with the percent change in AUC (= -0.742, p less than 0.01). These data demonstrated that the exogenous GH suppressed the GH response to GRF in prepubertal children with good response to GRF before exogenous GH, while it exaggerated the GH response to GRF in older children with relatively poor response before GH.

Adolescent↗
PubMed1990

[Longitudinal analysis of the development of pulmonary function in childhood].

In order to evaluate, longitudinally, the development of pulmonary function in childhood, maximal expiratory flow volume (MEFV) curves, height, and weight of 441 fourth grade school children were measured in 1980, and again two and four years later. The same instruments were used to measure pulmonary function, height, and weight in all three surveys. In addition, pulmonary function tests were performed by the same examiner in all three surveys. Three hundred and twenty five children had acceptable results for MEFV curves at all of three surveys. Two simple linear models were fitted to the distribution of pulmonary function measurements. One has age, height, functional level of the individual child, and the interaction of age and height as explanatory variables. In the other model, the natural logarithm of pulmonary function measurements was considered as a dependent variable, and age, height, and functional level of the individual child were employed as explanatory variables. The models explained the distribution of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and maximal expiratory flows (MEFs) quite well both in males and in females. These results suggest that the development of FVC and FEV1 against height was not linear, and that age was an independent contributor to the development even after adjusting for height. Tracking in the development of MEFs as well as FVC and FEV1 was observed, suggesting that functional development of MEFs for an individual child could be evaluated accurately utilizing percentile curves as in the case of FVC and FEV1.

Adolescent↗
PubMed1990

[The relationship between alveolar apertures and alveolar size and smoking history in humans, and experimental studies on air pollutants].

Using surgical specimens from patients with lung tumor, alveolar apertures and alveolar sizes were quantitatively assessed using scanning electron microscopy. Compared with smoking habits, increased apertures, defined as alveolar destruction were observed in patients smoking more than 35 years, whereas alveolar size was increased in patients, with a 15-year smoking history. Experimental studies with exposure to NO2, O3 and H2SO4 mist showed that exposure of NO2 and H2SO4 could induce epithelial injury such as disappearance of cilia in the central airways.

Adult↗
PubMed1989

Prolonged suppression of gonadotropin secretion after weight recovery in an anorectic patient with Turner's syndrome: reduced gonadal function in anorexia nervosa is independent in part on nutrition.

Two hypotheses have been postulated as to the pathogenesis of hypogonadotropinemia in anorexia nervosa; one is starvation and weight loss and the other is a psychological factor to influence gonadotropin secretion. Our patient suffered from very rare concurrence of Turner's syndrome and anorexia nervosa and a study of this experiment in nature provided important evidences concerning decreased secretion of gonadotropins in the eating disorder. The patient was diagnosed as Turner's syndrome when she was 6 years old. Her gonadotropin levels were elevated to the castrated ranges (LH 61.8 IU/l; FSH 175.8 IU/l) after 8 years of age. She was noticed to be anorectic at the age of 13 years. Serum levels of the pituitary gonadotropins were lowered (LH 2.9 IU/l; FSH 3.0 IU/l) and their responses to luteinizing hormone-releasing hormone were decreased beneath the normal prepubertal limits. After one year of the anorectic period, she recovered the weight though her gonadotropin levels remained in the very low ranges (LH 2.7 IU/l; FSH 2.5 IU/l). The results suggest that hypogonadism in anorexia nervosa is not solely caused by nutritional deficiency but rather by other factors such as psychological abnormalities.

Adolescent↗
PubMed1989

The influence of gonadal function and the effect of gonadal suppression treatment on final height in growth hormone (GH)-treated GH-deficient children.

One hundred and sixty-one children with idiopathic GH deficiency who received GH treatment were followed until they reached their final height. Final height was found to be influenced by gonadal function. In 108 patients who had spontaneous puberty (91 boys and 17 girls; group A), the mean final height was 151.8 +/- 6.6 (+/- SD) cm in boys and 141.7 +/- 7.4 cm in girls. In 29 patients with combined GH and gonadotropin deficiency (23 boys and 6 girls; group C), whose pubertal development was induced artificially at age 19.5 +/- 2.1 yr in the boys and 18.6 +/- 1.8 yr in the girls, the mean final height was 163.7 +/- 3.9 cm in boys and 151.0 +/- 5.1 cm in girls. The differences in final height between groups A and C were significant in both boys and girls. The shorter final height in group A was caused by the shorter pubertal duration and smaller pubertal height gain than those in normal children. In 24 patients (17 boys and 7 girls; group B) who developed early signs of puberty, gonadal suppression therapy with cyproterone acetate and/or medroxyprogesterone acetate was given. The mean SD score of the final height in these 24 patients was -2.1 +/- 0.6, significantly higher than that in group A. This beneficial effect of gonadal suppression treatment on final height was caused by increases in the duration of puberty and the pubertal height gain.

Adolescent↗
PubMed1989

[Monitoring of intracranial pressure in patients with brain tumors. Clinical study of the A wave mechanism].

Intracranial pressure (ICP) was continuously monitored in 70 patients with brain tumors. Simultaneous recording of respiration and systemic blood pressure was carried out in 20 and 13 cases, respectively. In 13 of the former 20 cases, blood gases were analyzed during typical A waves (Lundberg's A wave). In addition, in four cases cerebral blood flow (CBF) was measured during typical A waves. The A wave appeared when the baseline ICP exceeded 20 mmHg, and the higher the baseline pressure was, the more frequently the A wave was recorded. Three respiratory patterns occurred during typical A waves: hyperventilation, hypoventilation, and normal respiration. However, these respiratory patterns were not always clear-cut, and the three often were mixed. Systemic blood pressure during the typical A wave phase was either elevated (Cushing's response) or normal. All patients who showed Cushing's response had high baseline ICP and, with the frequently appearance of the A wave, had such symptoms of increased ICP as headache, nausea, and disturbance of consciousness. In all four cases studied, CBF decreased during typical A waves. These results, indicate that the A wave is associated with elevation of ICP and intracranial tightness. A particular region in the brainstem reportedly participates in the generation of the A wave. However, the mechanism of its development appears complex and involves such secondary factors as respiration and systemic blood pressure.

Adolescent↗
PubMed1989

[Treatment of the association of arteriovenous malformation and cerebral aneurysms].

The association of an arteriovenous malformation (AVM) and a cerebral aneurysm is not so rare. Many reports have analyzed its localized relationship and studied hemodynamically the development of the cerebral aneurysm. However its therapeutic measures have not been established so far. At this time, authors have experienced 9 cases of AVM associated with cerebral aneurysm, and have studied suitable therapeutic measures. All 9 cases developed with intracranial hemorrhage, and in 6 of 9 cases, cerebral aneurysm was recognized in the feeding arteries or feeding system of the AVM (Group I). In the other 3 cases, localization of cerebral aneurysm was hemodynamically considered to have less of a relationship with AVM (Group II). It was characteristic that cerebral aneurysm in Group I was multiple, and developed frequently in the peripheral regions of the cerebral artery, especially in feeding system of the AVM itself. An operation was carried out in all 9 cases, and in Group I, 2 of 6 cases were operated on in one stage. The other 4 cases because of difficulty of management in the same operative field, were divided into two stages. In cases with clearly hemorrhagic sources, operation was firstly performed on the hemorrhagic source, and its residual focus was operated on after several months. However, in cases with unknown hemorrhagic source, cerebral aneurysm existing on the proximal side was operated on firstly. On the other hand, in Group II, when the operation was performed at one or two stages, the hemorrhagic source was dealt with first.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

An attempt to assess the replacement dose of human growth hormone in the treatment of growth hormone deficient children.

In 25 patients with hGH deficiency, who had been treated long-term with hGH, the mode of hGH administration was switched from the conventional method (0.3-0.5 IU/kg/week, in two or three divided doses, intramuscularly) to daily subcutaneous injection at 1900-2100 hours with a dose of 0.46 +/- 0.07 IU/kg/week (equivalent to 14.7 +/- 2.0 IU/m2/week). After 1-3 months of this new mode of hGH administration, blood and urine were sampled at 0900 hours after overnight fasting. Blood glucose, plasma insulin, plasma IGF-1 and plasma total IGF (after extraction) were analysed in blood samples. IGF-1 and hGH were measured in urine samples. These measurements indicated that the dose studied was close to a replacement one, but might be slightly higher than the exact replacement dose.

Adolescent↗