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Biomedical subjects

S Higami

Publications and source records attributed to S Higami.

At least 19 recordsLinked to original sources
PubMed2004

A short daytime test using correlation dimension for respiratory movement in OSAHS.

In order to examine the pathology in patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS), the nonlinear properties of respiratory movement and breath-to-breath variations during resting wakefulness with eyes closed was investigated. Recording of the respiratory movement using inductive plethysmography was performed on 14 patients with OSAHS and 13 control subjects for 2 h in the supine position during daytime. To calculate the correlation dimension (D2) for respiratory movement, an algorithm proposed by Grassberger and Procaccia was applied. The indices of breath-to-breath variations were estimated. To calculate D2 and breath-to-breath variations, two different segments were selected (200 s each). The value of D2 for respiratory movement in patients with OSAHS was significantly greater than that in control subjects. In the case of > or = 2.0 of D2 for respiratory movement, the sensitivity and specificity of detecting the presence of OSAHS was 85.7% and 76.9%, respectively. On the basis of breath-to-breath variations, only the coefficient of variation of expiratory time for respiratory movement in patients with OSAHS was significantly greater than that in the control subjects. In conclusion, the measurements of correlation dimensions for respiratory movement with a brief period during wakefulness may be a useful index for identifying patients with obstructive sleep apnoea/hypopnoea syndrome.

Adult↗
PubMed2001

Cerebral metabolic impairment in patients with obstructive sleep apnoea: an independent association of obstructive sleep apnoea with white matter change.

OBJECTIVES: To determine the relation between severity of obstructive sleep apnoea (OSA) and degree of cerebral metabolic impairment. METHODS: Fifty five patients with habitual snoring and excessive daytime sleepiness underwent standard overnight polysomnography and magnetic resonance spectroscopy separately. Proton MR spectra were measured with two dimensional chemical shift imaging (repetition time; 1500 ms, echo time; 135 ms). Severity of cerebral metabolic impairment was assessed by the N-acetylaspartate (NAA)/choline ratios for the cerebral cortex and white matter. Severity of OSA was assessed by the apnoea-hypopnoea index (AHI) and the minimum value of peripheral oxyhaemoglobin saturation. All patients were evaluated for the presence or absence of comobidities including hypertension, cardiac disease, diabetes mellitus, and hyperlipidaemia. Univariate analysis of variance (ANOVA) and mulitple linear regression analysis were used for statistical analyses. RESULTS: Univariate ANOVA disclosed significant effects of AHI, age, and the presence or absence of hypertension on the NAA/choline ratio for cerebral white matter (p=0.011, p=0.028, p=0.0496, respectively). The AHI had a significant negative association with the NAA/choline ratio for cerebral white matter, independent of age and the presence or absence of cardiac disease, in the final multivariate regression model (standardised partial regression coefficient=-0.417, p<0.001). No significant relation was found between severity of OSA and the NAA/choline ratio for the cerebral cortex. Age alone had a significant effect on the NAA/choline ratio for the cerebral cortex on univariate ANOVA (p<0.001) and a significant negative association with the NAA/choline ratio for the cerebral cortex in the regression model (r=-0.552, p<0.001). CONCLUSIONS: A significant relation exists between AHI and the degree of metabolic impairment in cerebral white matter in patients with OSA.

Adult↗
PubMed2000

Relationship between hypersomnia and respiratory disorder during sleep in Prader-Willi syndrome.

To assess whether hypersomnia in Prader-Willi syndrome (PWS) patients is related to the respiratory disorder during sleep (RDDS), we made a systematic evaluation regarding the relationship between the two disorders in three patients. All patients showed hypersomnia manifested as the long duration of night sleep and shortened sleep latencies of multiple sleep latency test. Although magnetic resonance imaging and laboratory studies revealed obstruction of the upper airway and mild increase of esophageal pressure during sleep, the number of other apneic episodes or awakenings was not as frequent. From the above results, we speculate that the mechanism of excessive daytime sleepiness in PWS is not caused by RDDS and quite resembles that of essential hypersomnia.

Adolescent↗
PubMed2000

Clinical significance of negative esophageal pressure in sleep apnea syndrome.

The authors investigated the relationship between esophageal pressure fluctuation (DPes) during sleep and the following parameters: respiratory disorder variables and daytime sleepiness manifested as the Epworth sleepiness scale (ESS). In the younger patient group under 60 years of age (n=33), DPes was correlative to both the apnea-hypopnea index and ESS. However, in the elderly group of 60 years and over (n = 16), the variables showed smaller values than did those in the younger group. These results suggest that DPes may be associated with the aggravating process of sleep apnea syndrome (SAS) in the younger patient.

Adult↗
PubMed1999

Clinical efficacy of prosthetic mandibular advancement on obstructive sleep apnea syndrome.

In order to clarify the efficacy and indication of prosthetic mandibular advancement (PMA) on obstructive sleep apnea syndrome (OSAS), we made a comparison of both the polysomnographic findings and the upper airway configuration between before and during PMA on 19 OSAS patients. During PMA, there was a significant decreased apnea hypopnea index compared to before treatment. The changes in magnetic resonance imaging of the upper airway during sleep with PMA indicated that the treatment is regarded to be the first choice for OSAS patients with glossopharyngeal obstruction. In addition to that, the treatment might be considered for use in velopharyngeal obstruction.

Airway Resistance↗
PubMed1998

Mechanism of action and therapeutic indication of prosthetic mandibular advancement in obstructive sleep apnea syndrome.

Prosthetic mandibular advancement (PMA) was applied to nine patients with obstructive sleep apnea syndrome (OSAS) and its therapeutic usefulness, mechanism of action, and clinical indication were discussed based on polysomnographic findings and serial examination of upper airway before and during PMA treatment. Apnea hypopnea index significantly decreased during PMA treatment compared with the value before treatment (P < 0.01) and the rate of the treatment responder counted 78.1%. Cephalometric variables indicated forward and inferior advancement of mandible in our subjects. Magnetic resonance imaging of the upper airway during sleep revealed a marked improvement of velophanryngeal obstruction in most subjects. In addition, intraesophageal negative pressure during sleep decreased significantly. Our results confirmed the high therapeutic efficacy of PMA for OSAS and indicated forward advancement of the mandible and decrease of negative pressure loading on upper airway with PMA might suppress velopharyngeal collapse. Thus, PMA was regarded as one of the treatments of choice for OSAS occurring based on with velopharyngeal narrowing.

Adult↗
PubMed1998

[Retrospective analysis of the relationship between HUS incidence and antibiotics among patients with Escherichia coli O157 enterocolitis in the Sakai outbreak].

An outbreak of Escherichia coli O157:H7 infection occurred in July 1996 in Sakai City. About 5000 children were infected, 122 of whom developed hemolytic uremic syndrome (HUS). In this outbreak, almost all patients were administrated some type of antibiotics. The effects of antibiotics on E. coli O157 associated hemorrhagic colitis (HC) have been controversial. In this study, we focused on the effects of antibiotics on development of HUS in the HUS in the Sakai outbreak. We retrospectively determined the antibiotics administrated within three days after the onset of HC, clinical courses, and laboratory data of 301 patients who were hospitalized and identified as Escherichia coli O157 infection by stool culture, from results of questionnaires sent by the Osaka Prefecture Medical Association to hospitals in Osaka Prefecture. The antibiotics used could be identified for 216 patients. The incidence of HUS among these patients was 11.6%. They were divided into 19 groups based on the type of antibiotics administrated. The incidence of HUS in the new quinolone (3.7%) group was low, but was high in the intravenous cephalosporin (18.2%) group. The differences in the incidence of HUS among the 19 antibiotic groups was significant (p < 0.05) on analysis of covariance which eliminated the contributions of variables including age, sex and laboratory data. These findings indicate that the suitable antibiotics can prevent the development of E. coli O157-associated HUS.

Adolescent↗
PubMed1983

Immunofluorescence staining and immunological studies of arylsulphatase A of multiple sulphatase deficiency (MSD) and metachromatic leukodystrophy (MLD) fibroblasts.

Multiple sulphatase deficiency (MSD) and metachromatic leukodystrophy (MLD) are both characterized by a deficiency of arylsulphatase A (ARS A) activity, although they are inherited as separate autosomal recessive traits. However, it has been found that the immunologically active substance with anti-ARS A antibody is present in quite normal levels in MLD and in smaller quantities in MSD fibroblasts (Fiddler, 1979). Indirect immunofluorescence staining with anti-ARS A antibody displayed a coarse granular and diffuse distribution of ARS A or cross-reacting material (CRM) in the normal control and MLD fibroblasts, whereas very weak fluorescence staining was observed in MSD fibroblasts proportional to the decrease in the ARS A activity observed in the lysate enzyme assay. These results suggest that ARS A deficiency in MLD cells is due to an enzymatically deficient ARS A molecule, which is immunologically cross-reactive with anti-normal ARS A antibody. ARS A deficiency in MSD cells appears to be due to a reduced amount of normal ARS A.

Antibodies↗
PubMed1981

Cutaneous ultrastructural diagnosis of ceroid-lipofuscinosis.

A skin biopsy from a 6-year-old girl was examined by electron microscopy and the diagnosis of ceroid-lipofuscinosis (CL) was confirmed. This has not been reported in the dermatology literature, because of the absence of specific skin manifestations. However, as we have shown, various cells of skin, including fibroblasts, Schwann cells, eccrine serous cells, endothelial cells and smooth muscle cells, accumulated characteristic substances to produce the finger print pattern (FPP) or the curvilinear profile (CLP) which are thought to be diagnostic for CL. Cutaneous ultrastructural research in such cases is important as asymptomatic skin disorders may exist in other congenital storage diseases.

Ceroid↗
PubMed1978

Prenatal diagnosis and fetal pathology of Niemann-Pick disease.

Prenatal diagnosis was successfully accomplished by determining sphingomyelinase activity in the cultured amniotic fluid cells in a case of high risk pregnancy for Niemann-Pick disease (NPD), type A. No detectable activity of sphingomyelinase was found in the cultured amniotic fluid cells obtained at the 17th week of gestation. Patient's pregnancy was terminated and the aborted fetus was proved to be affected with NPD. The liver, brain and skin fibroblasts from the aborted fetus revealed a markedly diminished activity of sphingomyelinase. Sphingomyelin content in the liver of the affected fetus was found to be increased approximately sevenfold as compared with that in a control fetus liver. On the other hand, there was no increase of sphingomyelin in the brain from the affected fetus. No significant increase in cholesterol content was found in the liver and brain from the affected fetus. Electron-microscopic findings revealed membranous cytoplasmic bodies and electron dense material with vacuoles in cytoplasm of the liver cell and a number of Zebra body-like inclusions in the cerebral vessel wall. Biochemical and histological findings of the NPD fetus indicate that there is the progress of the disorder already in the midtrimester of gestation.

Amniotic Fluid↗
PubMed1976

alpha-L-iduronidase activity in leukocytes: diagnosis of homozygotes and heterozygotes of the Hurler syndrome.

The activity of alpha-L-iduronidase was determined in leukocytes from two patients with the Hurler syndrome, five obligatory heterozygotes, one patient with the Hunter syndrome, and ten normal individuals. It was found that the determination of alpha-L-iduronidase in leukocytes was a useful method for differential diagnosis between the Hurler and Hunter syndromes. Heterozygotes of the Hurler syndrome showed approximately 50% level of alpha-L-iduronidase activity in leukocytes as compared with that of normal individuals. This suggests that the determination of alpha-L-iduronidase activity may be available for the carrier detection of the Hurler syndrome.

Diagnosis, Differential↗
PubMed1976

Prenatal diagnosis and fetal pathology of Tay-Sachs disease.

In 6 cases of high risk pregnancies for Tay-Sachs disease, prenatal diagnosis was successfully carried out by examining hexosaminidase A activity in the supernatant of amniotic fluid and the uncultured and cultured amniotic fluid cells. In 5 out of 6 cases, the activity of hexosaminidase A was found to be within normal or heterozygous levels. They continued their pregnancies and were delivered of healthy children. In the remaining 1 case, the activity was undetected. Her pregnancy was terminated at the 23rd week of gestation. There was no activity of hexosamindase A in the brain and liver from the aborted fetus. A moderate increase in GM2 ganglioside was found in the brain. Electron-microscopic findings revealed membranous cytoplasmic bodies in the spinal ganglion cells as well as in the nerve cells of the retina. These biochemical and histological findings of Tay-Sachs fetus suggest that the disease proceeds early in fetal period. It was found that the cultured amniotic fluid cells was the most reliable material for the prenatal diagnosis of Tay-Sachs disease, because the values of hexoxaminidase A in the cultured cells were well in accord with those in serum from the consequently bord children. Hexosaminidase pattern in the supernatant of amniotic fluid on DEAE-cellulose columnchromatogram showed a distinct difference between homozygote, heterozygote and normal. This procedure also may be useful for prenatal diagnosis of Tay-Sachs disease.

Amniocentesis↗
PubMed1976

Lysine malabsorption syndrome: a new type of transport defect.

A 21-month-old girl with physical and mental retardation is described. She excreted an increased amount of lysine in urine but no excessive quantities of arginine, ornithine, or cystine. Serum level of lysine was found to be low but the levels of the other amino acids were within normal limits. The endogenous renal clearance rates of amino acids showed a marked high value of lysine and normal values of the other dibasic amino acids. Oral loading test of amino acids revealed an imparied absorption of lysine and normal absorption of arginine, ornithine, and cystine in the intestine. These results indicate a specific defect in transport of lysine in the intestine as well as in the renal tubule.

Amino Acids↗