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S Baba

Publications and source records attributed to S Baba.

At least 1,351 records · Page 75Linked to original sources
PubMedDate not supplied

Generation of fractal dimension images and its application to automatic edge detection in brain MRI.

We have developed four methods to generate a fractal dimension image and have applied them to the brain MRI. We have adopted four types of scanning methods, "CONVENTIONAL", "OVERLAPPING", "SYMMETRIC" and "FOLDED" to estimate the fractal dimension. The first three methods show almost the same fractal dimension images and their values were between two and three. In the "FOLDED" method, we were able to obtain the images in which the edge of a narrow region including dura and scalp surrounding the brain was selectively enhanced in the T1-weighted MRI. This is found to be a new edge-enhancing filter. We could remove the surrounding structure of the brain by using these filtered images and detect the edge of the brain surface automatically. The brain surface data can be used for various applications such as three-dimensional surface display and registration of inter-modal brain images.

Adult↗
PubMedDate not supplied

Development of microplate-radioluminography for 32P.

Basic research for designing a microplate which can be applied to determination of 32P by radioluminography was carried out. It was proven that 32P can be determined by using the microplate which has plural planchets placed at intervals on a thin plate and a brass collimator that fills the gaps between the planchets. The microplate is joined with the collimator, and exposed to an imaging plate for 24 h. The detection limit of the proposed method was estimated to be 6 m Bq. The cross-talk ratio was negligibly small (0.2%).

Microchemistry↗
PubMedDate not supplied

Immunohistochemical analysis of platelet-derived growth factor-B expression in myocardial tissues in hypertrophic cardiomyopathy.

Intimal and/or medial hyperplasia of intramyocardial small vessels is thought to be one of the causes of myocardial ischemia in hypertrophic cardiomyopathy (HCM). However, the pathogenesis of such vascular lesions in HCM is not yet known. To evaluate the pathogenic role of platelet-derived growth factor (PDGF-B) and basic fibroblast growth factor (b-FGF), which have a potential to induce cellular and molecular changes observed in the vessels in HCM, we examined the expression of these molecules and PDGF receptors in cardiac tissues from six patients with HCM and seven controls using immunohistochemistry. The percentage of PDGF-B positive cells in the myocyte population in HCM was significantly higher than that in controls (52.6 +/- 16.2 (mean +/- SD) vs. 21.6 +/- 9.6, p < 0.01). PDGF-B was also observed in vascular regions in HCM (61.1 +/- 25.5% of arterioles) but not in controls. There were no significant differences in the expression of b-FGF and PDGF receptors in the myocyte and non-myocyte populations and the vascular regions between the HCM and control groups. Our study revealed that the expression of PDGF-B protein was up-regulated in HCM, suggesting the contribution of this molecule to the development of intramyocardial vasculopathy.

Adolescent↗
PubMedDate not supplied

Effect of hydrocortisone on the synthesis of 2,3-diphosphoglycerate in human erythrocytes.

Studies were carried out on the mechanism of action of glucocorticoids on erythrocyte glycolysis. Inosine increased the levels of 2,3-DPG, lactate, and ATP in red blood cell samples with very low glucose concentrations in which the glycolytic system was unable to utilize glucose. With inosine and hydrocortisone added to red blood cells, 2,3-DPG and lactate increased more than in red blood cells supplemented with inosine alone. There was no significant increase in the level of ATP when glucose and inosine were added compared to the addition of inosine only. There were no changes in the activity of enzymes such as PFK and PGK. From these findings, it is suggested that glucocorticoids increase the level of red blood cell 2,3-DPG, by activating the conversion of 1,3-DPG to 2,3-DPG during glycolysis, probably by stimulating 2,3-DPG mutase.

2,3-Diphosphoglycerate↗
PubMedDate not supplied

Acquired and congenital cholesteatoma: determination of tumor necrosis factor-alpha, intercellular adhesion molecule-1, interleukin-1-alpha and lymphocyte functional antigen-1 in the inflammatory process.

The molecular and cellular factors resulting in the pathologic features of acquired and congenital cholesteatomas are not completely known. Recently, proinflammatory cytokines like interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) have been shown to induce bone resorption, in vitro. To elucidate the key molecules involved in bone resorption and cell infiltration associated with cholesteatoma, we examined the in vivo levels of IL-1 alpha and TNF-alpha, intercellular adhesion molecule-1 (ICAM-1) and lymphocyte functional antigen-1 (LFA-1) in acquired and congenital cholesteatomas, by reverse transcriptase-polymerase chain reaction, immunohistochemistry, and ELISA. Increased levels of IL-1 and TNF-alpha were detected in both types of cholesteatomas as compared to normal skin. Increased ICAM-1 expression and LFA-1+ cells were detected in acquired but not congenital cholesteatoma. Strong correlation was detected between TNF-alpha and bone resorption in both types of cholesteatoma, and between TNF-alpha and ICAM, TNF-alpha and severity of infection, or cell infiltration in acquired cholesteatoma. No correlation existed between various parameters and IL-1 alpha. These results suggest that TNF-alpha may play a crucial role in the pathogenesis of both acquired and congenital cholesteatomas by regulating bone resorption and cell infiltration.

Adult↗
PubMedDate not supplied

Plasma serotonin and platelet aggregation during ischemia-reperfusion in dogs: effect of dipyridamole and coenzyme Q10.

Platelet aggregation and plasma serotonin were studied during ischemia-reperfusion of the small intestine in dogs. Blood was withdrawn from the superior mesenteric vein before and 1 h after ischemia, then 5, 30 and 60 min after reperfusion. Dipyridamole (5 mg/kg body weight) and coenzyme Q10 (CoQ10; 10 mg/kg body weight) were administered intravenously 5 min before reperfusion, following 1 h ischemia, in order to investigate their effects on platelet function and free serotonin. Ischemia-reperfusion resulted in an increased local free serotonin concentration together with an enhanced platelet response to ADP, collagen and arachidonic acid. Administration of dipyridamole and CoQ10 prior to reperfusion prevented, at least in part, augmented platelet activation and serotonin release. It appeared that dipyridamole was more potent than CoQ10. Our results may indicate a possible protective effect of dipyridamole on enhanced platelet activation during ischemia-reperfusion in dogs.

Animals↗
PubMedDate not supplied

The pupillary light reflex in borderline diabetics.

Computerized IR videopupilography, using an open-loop photic stimulator, was used to compare the reflexes of borderline diabetics with overt non-insulin-dependent diabetics and with age- and sex-matched non-diabetic healthy controls. The patients were all male, aged 41-59 years. Overt non-insulin-dependent diabetics in their 40s had a smaller pupillary area and pupillary diameter prior to photic stimulus compared with borderline diabetics and healthy controls. Overt non-insulin-dependent diabetics in their 50s had a lower pupillary area and pupillary diameter prior to photic stimulus, maximum velocity and acceleration of constriction and maximum velocity of dilation than did borderline diabetics or controls. The only abnormality observed among borderline diabetics compared to controls was a smaller amplitude of constriction in response to light in patients in their 50s. Amplitude of constriction in response to light and velocity of constriction measurements of borderline diabetics, however, were considerably more frequently abnormal than were those of controls. The frequency of abnormal pupillary diameter prior to photic stimulus, maximum velocity of dilation and acceleration of constriction was higher in overt non-insulin-dependent diabetics than in borderline diabetics. The results indicate that borderline diabetics have autonomic neuropathy before the disease becomes overt. The importance of the pupillary light reflex examination is discussed.

Adult↗
PubMedDate not supplied

Acceleration of fructose mediated collagen glycation.

The effect of fructose on the formation of advanced Maillard reaction products which show fluorescence and have crosslinking was investigated. Type I collagen was added to various concentrations of glucose and fructose which were then incubated at 37 degrees C for 4 weeks. The level of furosine and the fluorescence intensity both increased in direct proportion to glucose and fructose levels and to the duration of incubation. Incubation with fructose produced less furosine but more intense fluorescence than incubation with glucose. Furthermore, collagen was significantly less soluble after incubation with fructose than after incubation with glucose. These results suggest that fructose in the polyol pathway plays an important role in the formation of advanced Maillard products.

Collagen↗
PubMedDate not supplied

Influence of serum protein levels on serum fructosamine levels.

The serum fructosamine level is influenced by the serum protein level. Therefore, we investigated the relationship between serum fructosamine levels and serum total protein and albumin levels measured simultaneously in non-diabetic and diabetic patients. Significant positive correlations were found between them. A correction formula was constructed to express the serum fructosamine level when the serum total protein level was 7 g/dl or when the serum albumin level was 4 g/dl: corrected fructosamine (mmol/l) = measured fructosamine (mmol/l) + A (7 (g/dl) or 4 (g/dl)--serum total protein (g/dl) or serum albumin (g/dl] where A is 0.28 for serum total protein and 0.30 for serum albumin in non-diabetic subjects; 0.29 for serum total protein and 0.31 for serum albumin in non-diabetic and diabetic subjects combined.

Blood Glucose↗
PubMedDate not supplied

Clinical features of diabetes mellitus in Japan.

The first Symposium on Diabetes Mellitus in Asia was held in Kobe, Japan, in 1970 and the second symposium in Kyoto, Japan, in 1975. These two symposia raised many questions. Participants from various countries compared their findings on the frequency of diabetes and its complications. Such comparisons are usually complicated because of the differences in diagnostic criteria used, the age groups compared, and duration of diabetes observed, etc. In spite of these problems, careful analysis and close comparisons may offer important clues as to the pathogenesis of diabetes and the factors related to its complications. Japanese and Caucasian diabetes have some differences resulting from the Japanese diabetic pathophysiologic, ethologic, and ecologic factors. In this paper, diabetes is discussed from an ecologic viewpoint, especially characteristics of the disease and its prognosis in relation to the complications and food habits in Japan.

Adolescent↗
PubMedDate not supplied

Hemoglobin A1 properties of diabetic and uremic patients.

Patients with diabetes mellitus as well as those with renal failure had high hemoglobin A1 (HbA1) levels. However, the portion of HbA1a+b fractions was larger in patients with renal failure than in diabetic patients. Thus, if renal disorder is advanced, caution should be exercised in evaluating HbA1 data. Furthermore, not only is the collective determination of Hb minor components such as HbA1 required, but also investigation of changes in HbA1a+b in patients with renal failure or diabetic nephropathy.

Diabetes Mellitus↗
PubMedDate not supplied

Low frequency of 5'-flanking insertion of human insulin gene in Japanese non-insulin-dependent diabetic subjects.

Polymorphism in the 5'-flanking region of the human insulin gene in 149 unrelated Japanese subjects [77 with non-insulin-dependent diabetes mellitus (NIDDM), 17 with insulin-dependent diabetes mellitus (IDDM), and 55 controls] was analyzed with Southern blot hybridization. We used the size of the hybridized fragments to classify the locus into three groups according to Bell's method (a short, class 1 allele averaging 570 base pairs; an intermediate-size, class 2 allele averaging 1320 base pairs, and a long, class 3 allele averaging 2470 base pairs in size). The allelic frequency of classes 2 and 3 in 298 alleles was 5.0% and in the 146 alleles of NIDDM, 7.8%. The value is lower than in Caucasians, American Blacks, and Pima Indians, and the results suggest that the 5'-flanking insertion is not a genetic marker in most NIDDM patients who are Japanese. However, the frequency of the 5'-flanking insertion in those who were not obese and had a family history of diabetes was higher than that of other NIDDM patients (P = .013), and the frequency in NIDDM patients with onset of diabetes at age less than or equal to 39 yr was lower than those whose onset was at age greater than or equal to 40 yr (P = .053). As NIDDM is a heterogeneous disorder, further analysis is needed. These results suggest that we cannot completely exclude the meaning of the insertion in NIDDM. On the other hand, the frequency in IDDM was 0%, lower than in NIDDM (P = .094). Because the number of subjects studied was small, this result is speculative.

Adult↗
PubMedDate not supplied

A study of the relationship between the T&T olfactometer and the University of Pennsylvania Smell Identification Test in a Japanese population.

The University of Pennsylvania Smell Identification Test (UPSIT) and a smell ability questionnaire were administered to 167 Japanese volunteers ranging in age from 20 to 59 years. Of these subjects, 80 also received the T&T olfactometer threshold test. Of the latter subjects, 36 were patients tested before endoscopic nasal surgery for sinusitis and polyposis. The patients exhibited decreased smell function, as measured by the T&T olfactometer, the UPSIT, and a 30-item version of the UPSIT in which the 10 least familiar items were removed (ps < 0.001). Spearman correlations ranging from 0.53 to 0.70 were found between (i) scores on the 30- and 40-item UPSITs and (ii) the T&T detection and recognition threshold values. Significant correlations were found between scores on the smell ability questionnaire and the olfactory test measures (UPSIT30 r = 0.56; UPSIT40 r = 0.58; T&T detection r = 0.56; T&T recognition r = 0.69, p < 0.001), indicating that subjects are relatively accurate in assessing their olfactory ability. This study suggests that the 30 and 40-item UPSITs correlate well with measures derived from the T&T olfactometer, and that all three tests are sensitive to the smell loss of Japanese sinusitis/polyposis patients.

Adult↗
PubMedDate not supplied

Clarithromycin suppresses proliferation of rat nasal epithelium exposed to endotoxin.

A study was performed to elucidate the action of long-term macrolide therapy in chronic sinusitis. Clarithromycin (CAM) was administered orally once daily for 14 days. On the last 3 days, an endotoxin, lipopolysaccharide (LPS) was instilled intranasally. The extent of DNA synthesis acceleration was studied in both controls and pretreated animals by counting the number of 5-bromo-2'-deoxyuridine (BrdU)-labeled cells in the nasal transitional epithelium. Six hours after the final intranasal instillation of LPS, the number of BrdU-positive cells was significantly higher than control. Pretreatment with CAM for 2 weeks significantly inhibited this increase. Because similar results were obtained in neutrophil-depleted rats, LPS apparently promotes proliferation of the nasal epithelium in the absence of neutrophils: CAM-suppressed epithelial proliferation independently of the neutrophil count. Our results suggest that CAM inhibits LPS-induced increased rates of DNA synthesis by directly affecting the nasal epithelium. The mechanism by which macrolide therapy alleviates the signs and symptoms of chronic sinusitis might therefore involve suppression of inflammatory processes in the nasal and paranasal sinus epithelium.

Animals↗
PubMedDate not supplied

Electrocochleographic analysis of the suppression of tinnitus by electrical promontory stimulation.

To investigate the origin, and evaluate the mechanism by which tinnitus is suppressed we performed electrical promontory stimulation (EPS) in 56 patients with tinnitus, and measured the compound action potential (CAP) using electrocochleography before and after EPS. In the group of patients in whom tinnitus was suppressed, the CAP amplitudes increased significantly, whereas the latencies showed no remarkable change. In the group of patients in whom tinnitus was not suppressed, both the CAP amplitudes and latencies exhibited no significant change. These data indicate that the effect on the cochlear nerve plays an important role in the suppression of tinnitus by EPS. The CAP reflects the number of the auditory nerve fibers which discharge synchronously. It is speculated that an increase of the CAP amplitudes is caused by synchronizing discharges of the auditory nerve fibers, and that the mechanism by which EPS suppresses tinnitus may be related to synchronizing these discharges.

Adult↗
PubMedDate not supplied

Progression of prostate cancer: diagnostic and prognostic utility of prostate-specific antigen, alpha2-macroglobulin, and their complexes.

We previously reported cases of advanced prostate cancer (PCa) in which serum alpha2-macroglobulin (alpha2M) levels were markedly decreased to less than approximately 50 mg/dl whereas serum prostate-specific antigen (PSA) levels were remarkably increased. These cases were not complicated with disseminated intravascular coagulation (DIC). In this study, we measured serum PSA and alpha2M in 108 patients with either benign prostatic hyperplasia (BPH) or PCa to elucidate the relationship between PSA, i.e. the serum protease derived from the prostatic tissue, and alpha2M, i.e. the protease inhibitor that was the most abundantly contained in serum. alpha2M was determined by ELISA, total PSA and PSA-alpha1-antichymotrypsin (PSA-ACT) by EIA, and free-PSA by RIA in 44 patients with untreated BPH and 64 patients with untreated PCa. The ready association of alpha2M and PSA was assessed using Western blotting to identify complexes of the two. Levels of total serum PSA correlated positively with those of PSA-ACT in PCa (r = 0.99, p < 0.001), and both levels increased with advancing stage of disease. In contrast, the serum-free PSA/total PSA ratio (free/total PSA) and alpha2M levels decreased as the disease progressed. However, only the free/total PSA ratio attained significant difference for localized cancer in stage T1,2 versus BPH (p < 0.05). In stage M1b PCa, in which serum PSA levels were very high, there was a negative correlation between the total PSA and alpha2M values (r = -0.57, p < 0.05). In addition, serum alpha2M levels tended to decrease with progression of PCa. Serum total PSA levels correlated tightly with serum PSA-ACT levels. It is suggested that PSA is usually complexed with ACT in the serum. Free/total PSA was useful for differential diagnosis between early cancer and BPH. Levels of serum alpha2M of less than 50 mg/dl in PCa patients may indicate a possibility of bone metastases.

Aged↗