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S Tomizawa

Publications and source records attributed to S Tomizawa.

At least 19 recordsLinked to original sources
PubMed2005

Distinction between some saccharides in scattered optical sum frequency intensity images.

Using an optical sum frequency (SF) microscope with visible and infrared light pulses for excitation, we have attempted to distinguish among four saccharide species. The saccharides we studied were d-glucose, amylopectin, beta-cyclodextrin, and amylose. The wavelength of the infrared light was resonant to CH vibration. Amylose showed very weak sum frequency scattering for CH vibration among the four saccharides. As for the other three saccharides, we found a big difference in the sum frequency spectra of their CH stretching vibration near 2900 cm-1, when the incident visible and infrared light pulses were p- and s-polarized, respectively. Based on these facts, we have demonstrated a distinction between these three saccharides in the scattered SF intensity images.

Amylopectin↗
PubMed2001

Percutaneous transvenous embolisation through the occluded sinus for transverse-sigmoid dural arteriovenous fistulas with sinus occlusion.

We report six cases of transverse-sigmoid dural arteriovenous fistulae (TS DAVF) treated with percutaneous transvenous embolisation through the occluded sinus. All patients had sinus occlusive lesions: an isolated sinus in five cases and a distal occlusion of the affected sinus in one. Leptomeningeal retrograde venous drainage via the vein of Labbé or the sylvian vein was observed in all patients with an isolated sinus. In five patients a microcatheter was easily passed through the occluded sinus. In four of them, a complete angiographic cure was achieved by packing the sinus with coils. However, in one, sinus packing was ineffective and surgical excision of the affected sinus was necessary. The microcatheter could not be passed through the occluded sinus in one case, and direct packing of the isolated sinus was later required. In all cases, complete cure was achieved without complications. This safe, not very invasive and highly effective treatment for TS DAVF with sinus occlusion is thus worth trying when the occluded segment is relatively short.

Aged↗
PubMed2001

Prognosis of acute poststreptococcal glomerulonephritis (APSGN) is excellent in children, when adequately diagnosed.

BACKGROUND: Recently, the prognosis of acute poststreptococcal glomerulonephritis (APSGN) has been reported as improved, compared with the results of previous studies. In an attempt to clarify this, we analyzed the clinical course of patients with APSGN. METHODS: A total of 220 children with acute nephritic syndrome were treated in the affiliated hospitals of our department, between January 1988 and December 1997. Among them, 138 children who were diagnosed with APSGN according to the presence of hematuria, transient hypocomplementemia and evidence of group A beta-hemolytic streptococcal infection, were studied. RESULTS: Serum creatinine and blood urea nitrogen levels at onset were 0.5 +/- 0.2 mg/dL and 20 +/-12 mg/dL, respectively. There were no patients with renal dysfunction (serum creatinine level > or = 1.5 mg/dL), but one patient with nephrotic syndrome. Blood pressure was well controlled in all patients and there were no patients with persistent hypertension. Serum complement levels were normalized within 12 weeks (100%), hematuria disappeared within 4 years (100%) and proteinuria disappeared within 3 years (100%) from the onset. CONCLUSIONS: These data indicate that the prognosis of APSGN during childhood is excellent, when adequately diagnosed and treated.

Acute Disease↗
PubMed2001

Characterization of 5'-flanking region of rat somatostatin receptor sst2 gene: transcriptional regulatory elements and activation by Pitx1 and estrogen.

The sst2 somatostatin receptor mediates the inhibitory effects of somatostatin on secretive and proliferative processes. We previously showed that sst2 is one of the major subtypes expressed in the rat pituitary, and its messenger RNA level is up-regulated by chronic treatment with estrogen. To investigate the molecular mechanisms regulating sst2 gene expression, we cloned the upstream region (9.5 kb) from the translation initiation codon of the rat sst2 gene. It contained a single intron (5.0 kb) at the 5'-untranslated region, lacked TATA and CCAAT boxes, and had multiple transcriptional start sites. Transient transfection analysis with deleted mutants of a luciferase reporter construct showed that the promoter activity was regulated negatively and positively in the distal and proximal promoter regions, respectively. The promoter activity of each construct was more efficient in GH(3) pituitary cells than in nonpituitary cells. The construct (-77/+172/luc) containing a cAMP response element (CRE; -54/-47) provided maximum promoter activity, but a further 5'-deleted construct dramatically reduced the activity. Competitive gel shift and supershift assays indicated that Sp2 and Sp3 were bound to an Sp1 site (-40/-31), and activating transcription factor-2 and c-Jun were bound to a CRE site. Both Sp1 and CRE sites were essential for the full promoter activity. Overexpression of the pituitary homeoprotein Pitx1 activated the promoter activity of the -4066/+172/luc construct, and mapping analysis indicated the existence of two Pitx1 response sites, including the CRE site. Estrogen also increased the promoter activity of -77/+172/luc in GH(3) cells or in HeLa cells overexpressing both the estrogen receptor and c-Jun. These studies demonstrated the nature of the rat sst2 gene and the functional importance of both Sp1 and CRE sites in regulating sst2 gene expression and suggest that the CRE site mediates, at least partly, the promoter activity activated by Pitx1 or estrogen.

5' Untranslated Regions↗
PubMed1998

Difference in topology and numbers of barosensitive catecholaminergic and cholinergic neurons in the medulla between SHR and WKY rats.

We hypothesized that there may be a significant difference in the neuronal composition of the baroreceptor reflex pathway between normotensive Wistar Kyoto (WKY) and spontaneously hypertensive SHR rats. Using the double-immunoreactive (IR) method, the topology and numbers of barosensitive neurons that contain glutamate (Glu), glutamic acid decarboxylase (GAD), tyrosine hydroxylase (TH), phenylethanolamine N-methyltransferase (PNMT) and choline acetyltransferase (ChAT) were compared between the two strains. The control rats were sham-operated only for cannulation of the trachea and femoral artery/vein. The test rats were injected with the pressor agent phenylephrine to raise blood pressure and stimulate arterial baroreceptors. In both the control and test experiments, the c-Fos/Glu-, GAD-, TH- and PNMT-IR neurons were found in the nucleus tractus solitarii (NTS) and ventrolateral medulla (VLM), while the FosB/ChAT-IR neurons were found in the NTS, dorsal motor nucleus of the vagus (DMX) and nucleus ambiguus (AMB). In the control experiment, no significant difference in numbers was recognized in any of the double-IR neurons between the two strains. In the test experiment, the numbers of FosB/ChAT-IR neurons in the NTS, DMX and AMB were significantly smaller in SHR than in WKY. The numbers of c-Fos/TH-IR neurons in the caudal VLM were significantly larger in SHR than in WKY. These results suggest that a smaller number of barosensitive cholinergic neurons in the DMX and AMB in SHR causes the weaker baroreceptor-cardiac vagal reflex in SHR, and that a larger number of barosensitive catecholaminergic neurons in the caudal VLM in SHR are involved in the stronger baroreceptor-vasopressin reflex in SHR.

Animals↗
PubMed1998

Influence of age at onset on the outcome of steroid-sensitive nephrotic syndrome.

To investigate whether age at onset of steroid-sensitive nephrotic syndrome (SSNS) is predictive of subsequent relapses, or influences outcome, we retrospectively studied 60 patients who were under 10 years of age at onset and were followed for over 10 years. They were divided into three groups according to age at diagnosis: group 1-3 (1.0-3.9 years at onset, n=24), group 4-6 (4.0-6.9 years at onset, n=22), and group 7-9 (7.0-9.9 years at onset, n=14). In the 51 patients with long-term remission, defined as remaining relapse-free over 3 years, the total number of relapses was significantly more in group 1-3 (n=18) than in group 4-6 (n=19), and the interval between onset and long-term remission was significantly longer. Group 4-6 and group 7-9 had fewer patients with active disease at 10 years, follow-up than group 1-3, as assessed by the Kaplan-Meier method. These data suggest that the age at onset of SSNS influences the clinical course (i.e., frequency of relapses) and the time to reach long-term remission. An age of less than 4 years at onset of SSNS is associated with greater likelihood for frequent relapses and a greater time interval to attain long-term remission.

Age of Onset↗
PubMed1998

Chronic treatment with estrogen up-regulates expression of sst2 messenger ribonucleic acid (mRNA) but down-regulates expression of sst5 mRNA in rat pituitaries.

We previously showed that 17beta-estradiol (E2) induces the somatostatin (SRIF) responsiveness of the rat anterior pituitary, which leads to inhibition of PRL secretion through E2-dependent SRIF receptors. To examine receptor subtypes regulated by E2, we determined the messenger ribonucleic acid (mRNA) levels of all subtypes using a semiquantitative RT-PCR and characterized pituitary membrane receptors using subtype-preferential SRIF analogs. Most of the SRIF receptor subtype mRNAs were sst5 and sst2A in ovariectomized rat pituitaries [sst5/glyceraldehyde 3-phosphate dehydrogenase (GAPDH) = 1.4 x 10(-2), sst2A/GAPDH = 0.4 x 10(-2)]. The expression pattern of the subtypes in ovariectomized rat pituitaries was similar to that of normal male and female rat pituitaries, although the mRNA levels of sst5 and sst2A in male rat pituitaries were higher than in females. Chronic administration (4 weeks) of E2 to the ovariectomized rats increased mRNA expression of sst2A, sst2B, sst3, and sst1 and drastically decreased expression of sst5; the transcripts of sst2 isoforms constituted 87% of total SRIF receptor subtype mRNAs (sst2A/GAPDH = 1.2 x 10(-2)), whereas the sst5 mRNA level was less than 1%. Receptor-binding studies revealed that in pituitaries from both ovariectomized rats and male rats, heterogeneous receptor types, probably sst5 and sst2, were expressed, whereas receptors from E2-treated rat pituitaries mostly exhibited characteristics of the sst2 subtype. The results demonstrated that sst5 and sst2A were the major subtypes expressed in normal rat pituitaries with a sex-dependent difference and that whereas E2 up-regulates the expression of sst2 isoforms, it down-regulates the expression of sst5, suggesting roles for these subtypes in the control of pituitary functions.

Animals↗
PubMed1997

Lipoprotein glomerulopathy: a pediatric case report.

We report an 8-year-old girl with lipoprotein glomerulopathy who may have developed this condition as young as 4 years of age. To our knowledge this is the youngest reported case of this disease. Lipid studies of the patient and her family members revealed elevated concentrations of apolipoprotein E (apo E), the apo E phenotype E2/3, and the genotype E3/3. However, other families revealed no urinary abnormalities. Our findings suggest that an apo E abnormality may be responsible for the development of lipoprotein glomerulopathy. Genetic analysis of apo E is needed to clarify the pathogenesis.

Apolipoproteins↗
PubMed1996

Separated ossicles of the lateral malleolus.

Sixty ankles of 59 patients with symptomatic ossicles of the lateral malleolus were studied. All patients underwent clinical and radiographic examinations. Stress arthrography was performed on 58, arthroscopy on 48, operative treatment on 52, and histologic examination on 23. The ossicles were classified into 3 sizes (small, medium, and large) and 2 levels (A and B) by location. The relationship between the ossicle and fibular tip was classified into 3 grades according to arthrography results (Grade 1, little inflow [< 1 mm] of the contrast medium; Grade 2, an apparent space [1-2 mm]; Grade 3, a large gap [> 2 mm]) and to operative and arthroscopic findings (Type A, a fibrous union; Type B, a partial continuity; Type C, a lax thin scar tissue; Type D, no continuity). There were significant differences in talar tilt angles on stress radiography between the 3 grades. Chronic symptoms had a tendency to increase from Grade 1 to Grade 3 and from Type A to Type C or D, with instability occurring more than pain. The size and level did not correlate with instability. Acute or chronic inversion forces may act on the connection between the ossicle and fibular tip, and damage to this structure may cause symptoms.

Adolescent↗
PubMed1996

[Crystal forms, improvements of dissolution and absorption of poorly water-soluble (R)-1-[2,3-dihydro-1-(2'-methylphenacyl)-2-oxo-5-phenyl-1H-1, 4-benzodiazepin-3-yl]-3-(3-methylphenyl)urea (YM022)].

Polymorphs of (R)-1-[2,3-dihydro-1-(2'-methylphenacyl)-2-oxo-5-phenyl-1H-1,4- benzodiazepin-3-yl]-3-(3-methylphenyl)urea (YM022) were investigated. Two crystalline forms (alpha- and beta-forms) of YM022 were confirmed by powder X-ray diffractometry and differential scanning calorimetry. alpha- And beta-forms were obtained by recrystallization from ethanol and ethanol: water (5:1), respectively. Amorphous YM022 was obtained by spray drying of YM022 methanol solution. Since both crystalline and amorphous YM022 were sparingly soluble in water, solubilization of YM022 by solid dispersion and wet grinding methods were performed. In vitro dissolution study and in vivo absorption study in dogs were carried out using spray-dried solid dispersion, heat-treated solid dispersion and mechanical mixture. Spray-dried solid dispersion and heat-treated solid dispersion showed enhanced bioavailability, whereas mechanical mixture showed no improvement.

Animals↗
PubMed1995

C9 deficiency in a patient with poststreptococcal glomerulonephritis.

The case of a 10-year-old girl with congenital C9 deficiency and poststreptococcal glomerulonephritis (PSGN) is presented. Although her clinical symptoms mimicked those of Henoch-Schönlein purpura, histological examination of a renal biopsy specimen revealed the features commonly described in PSGN.

Child↗
PubMed1994

Reversed-phase high-performance liquid chromatography for analysis of urinary proteins: diagnostic significance of alpha 1-acid glycoprotein.

In order to analyze urinary proteins from patients with various renal diseases, a reversed-phase high-performance liquid chromatography with IPG PACK ODS column packed with polyporous glass was employed. The peak areas of alpha 1-acid glycoprotein (alpha 1-AGP), beta 2-microglobulin (beta 2-MG) and albumin were measured by a chromato-integrator. The alpha 1-AGP/albumin ratio was regarded as the marker of glomerular damage, while the beta 2-MG/albumin ratio indicated tubular dysfunction. As a result, the alpha 1-AGP/albumin ratio in the urine from patients with either various glomerulonephritis (GN) or idiopathic nephrotic syndrome was significantly higher than that from either patients with postural proteinuria or healthy children. However, the beta 2-MG/albumin ratio in the urine from patients with GN was the same level as controls. The beta 2-MG/albumin ratio was elevated only in urine from patients with tubular dysfunctions. These data suggest that the urinary alpha 1-AGP/albumin ratio could be a beneficial indicator in locating patients with GN from among children with asymptomatic proteinuria.

Albuminuria↗
PubMed1994

Purification of two types of TNF inhibitors in the urine of the patient with chronic glomerulonephritis.

In order to clarify whether TNF inhibitory activity in the urine of glomerulonephritis (GN) patients depends on the existence of TNF inhibitors/soluble TNF receptors, we purified two types of TNF inhibitors from the urine of chronic renal failure (CRF) with GN patient. Using four steps of chromatography (anion exchange chromatography, preparative reverse phase chromatography, TNF affinity chromatography, analytical reverse phase chromatography), two types of 99% pure TNF inhibitors were purified. Amino terminal amino acid sequence revealed that one inhibitor was identical to soluble TNF receptor, p55, however, the other was homologous but not identical to soluble TNF receptor, p75. Our experiments demonstrated that TNF inhibitory activity in the urine of CRF patients depended partly on the existence of soluble TNF receptors in the urine.

Amino Acid Sequence↗
PubMed1993

Fatal pulmonary haemorrhage and crescentic glomerulonephritis without autoantibodies: a paediatric case report.

The case of an 8-year-old girl who had a fatal pulmonary haemorrhage and crescentic glomerulonephritis without autoantibodies is presented. Circulating anti-glomerular basement membrane antibodies, circulating immune complexes and anti-neutrophil cytoplasmic autoantibodies were not detected. To our knowledge this is the youngest reported case of the disease.

Antigen-Antibody Complex↗
PubMed1992

Inhibition of vascular permeability factor production by ciclosporin in minimal change nephrotic syndrome.

In order to ascertain whether ciclosporin (Cs) has an inhibitory effect on the vascular permeability factor (VPF) production, various quantities of Cs were added to T lymphocyte cultures from 8 children with minimal change nephrotic syndrome (MCNS) and the VPF activity of culture supernatants was assayed. As a result of the addition of Cs, a dose-dependent inhibition of VPF production was seen. VPF production was inhibited by a level of between 100 and 250 ng/ml of Cs in vitro. The reduction of proteinuria by Cs in MCNS might be due to the inhibition of VPF production.

Animals↗