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Biomedical subjects

S Kobayashi

Publications and source records attributed to S Kobayashi.

At least 73 records · Page 4Linked to original sources
PubMed2004

Midbrain hypometabolism as early diagnostic sign for progressive supranuclear palsy.

OBJECTIVE: Progressive supranuclear palsy (PSP) is often misdiagnosed in early phase. The purpose of this study is to investigate the feature of [(18)F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography images for the early diagnosis of PSP. METHODS: We studied 15 patients with PSP and 16 normal subjects. Using SPM99 and analysis of covariance to eliminate the effect of aging, the differences between PSP and normals were displayed as a statistical map. In the PSP, we also investigated the correlation with duration and with the subscores of Unified Parkinson's Disease Rating Scale. RESULTS: The glucose metabolism of midbrain was significantly lower in PSP than in normals. However, correlation was not found between the metabolism of midbrain and clinical deterioration. CONCLUSIONS: The statistical map clearly demonstrated the hypometabolism of midbrain in PSP, which is independent of the clinical deterioration. The hypometabolism of midbrain is one of the most promising sign for early diagnosis of PSP.

Adult↗
PubMed2004

Radiographic examination of the mandibular (glenoid) fossa in ancient and modern man.

OBJECTIVE: To compare the morphology of the mandibular (glenoid) fossa between ancient and modern Japanese. METHODS: There were 221 specimens from the ancient period and 206 specimens from the modern period. Radiographs of the mandibular fossa were obtained using a modified Schuller technique and were studied. The length, depth, and area of the mandibular fossa and angulation of the frontal slope of the mandibular fossa on the radiographs were automatically computed. In addition, morphological changes of the mandibular fossa in the ancient or modern periods on radiographs were evaluated in order to assess tendency of temporomandibular joint disorder (TMD). RESULT: The ratio of mandibular fossa having morphological alternation in the modern period was greater than that in the Yayoi. Differences in the length and area between the right and left sides became progressively larger from the Yayoi to modern periods. The angulation of the anterior slope of the mandibular fossa in the modern period was smaller than that in other periods. CONCLUSION: The morphology of the mandibular fossa was shown to have changed and asymmetry has increased from the Yayoi to modern periods. It can be speculated that this change in morphology of the mandibular fossa in the modern period is the result of an increase of TMD.

Cephalometry↗
PubMed2004

Fluoride mouth rinsing proficiency of Japanese preschool-aged children.

AIM: To determine whether Japanese preschool-aged children swallow fluoride solution while rinsing and how much fluoride was retained in the mouth after rinsing. METHODS: The subjects were 769 children who participated in a school-based fluoride mouth rinse programme (FMR) using 0.05% sodium fluoride solution daily. The group of younger, mean age of 4 years and 10 months, experienced the FMR for two months, and the group of older children, mean age of 5 years and 4 months, did it for at least 8 months, rinsing for a minute using 7 ml of the solution. The amount of fluoride retained in the mouth was estimated as the amount present in the net rinsing solution prepared minus what returned to the solution expectorated. RESULTS: No child swallowed all the solution. The rate of fluoride retained was 12.0% (mean = 0.19 mg) in the younger group and 10.7% (mean = 0.17 mg) in the older. Only six children retained over 0.5 mg of fluoride. With the extra survey using weekly intervals, the amount retained was below 0.5 mg in all children. CONCLUSION: That Japanese preschoolaged children could perform fluoride mouth rinsing safely and efficiently.

Age Factors↗
PubMed2004

Protein composition of human metaphase chromosomes analyzed by two-dimensional electrophoreses.

A large amount of metaphase chromosomes were isolated from synchronized human cell lines by a polyamine procedure. All the chromosomal proteins extracted by an acetic acid extraction method were fully dissolved into the sample solutions for isoelectric focusing (IEF) or radical free and highly reduced (RFHR) two-dimensional electrophoreses (2-DEs). As a result, well-separated and highly reproducible 2-DE patterns were obtained. This could not be attained by an ordinary acetone precipitation method. The 2-DE patterns visualized using Coomassie Brilliant Blue (CBB) staining indicated that more than one hundred proteins were involved in the isolated metaphase chromosomes, although the most abundant proteins, histones, occupied a greater part of the chromosomal proteins. It was also shown that colcemid treatment for cell cycle synchronization had little effect on the 2-DE pattern compared to that obtained without the treatment. Furthermore, no significant differences were observed in the 2-DE patterns among the chromosomal proteins prepared from two different human cell lines, BALL-1 and K562. However, 2-DE analysis of isolated metaphase chromosomes from HeLa cells apparently showed a smaller number of proteins than the BALL-1 and K562 cell lines at a neutral pI range. The present study paves the way for elucidating protein composition of human metaphase chromosomes.

Cell Line, Tumor↗
PubMed2004

Ubc9 interacts with chicken ovalbumin upstream promoter-transcription factor I and represses receptor-dependent transcription.

Chicken ovalbumin upstream promoter-transcription factors (COUP-TFs) are orphan receptors involved in regulation of neurogenesis and organogenesis. COUP-TF family members are generally considered to be transcriptional repressors and several mechanisms have been proposed to underlie this activity. To explore novel transcriptional coregulators for COUP-TFs, we used the COUP-TFI as bait in a yeast two-hybrid screen of an adrenocortical adenoma cDNA library. We have identified Ubc9, a class E2 conjugating enzyme of small ubiquitin-related modifier (SUMO)-1 as a COUP-TFI corepressor. Ubc9 interacts with COUP-TFI in yeast and in glutathione S-transferase pulldown and coimmunoprecipitation assays. Fluorescence imaging studies show that both Ubc9 and COUP-TFI are colocalized in the nuclei of transfected COS-1 cells. The C-terminal region of Ubc9 encoding amino acids 59-158 interacts with the C-terminus of COUP-TFI encoding amino acids 383-403, in which transcriptional repression domains are located. Mammalian one-hybrid assays utilizing a variety of Ubc9 fragments fused to Gal4 DNA-binding domain show that a Ubc9 fragment encoding amino acids 1-89 contains autonomous transferrable repression domain. Transfection of Ubc9 into COS-1 cells markedly enhances transcriptional repression by Gal4 DNA-binding domain-fused to COUP-TFI(155-423), but not by Gal4-COUP-TFI(155-388) which lacks a repressor domain. Coexpression of a C-terminal deletion mutant of Ubc9(1-58), which fails to interact with COUP-TFI, but retains a transcriptional repression domain, has no effect on Gal4-COUP-TFI-mediated repression activity. These findings indicate that interaction of Ubc9 with COUP-TFI is crucial for the corepressor function of Ubc9. Overexpression of Ubc9 similarly enhances COUP-TFI-dependent repression of the promoter activity of the bovine CYP17 gene encoding steroid 17alpha-hydroxylase. In addition, the C93S mutant of Ubc9, which abrogates SUMO-1 conjugation activity, continues to function as a COUP-TFI corepressor. Our studies indicate that Ubc9 functions as a novel COUP-TFI corepressor, the function of which is distinct from its SUMO-1 conjugating enzyme activity.

Animals↗
PubMed2004

Diurnal rhythm of cerebrospinal fluid and plasma leptin levels related to feeding in non-lactating and lactating rats.

Leptin suppresses food intake and increases energy expenditure in the hypothalamus. Rats consume most of their daily food intake during the dark phase of the diurnal cycle. Lactating rats have increased food intake, but the involvement of leptin in the regulation of food intake in this physiological condition is not well understood. The present experiment was carried out to determine the circadian pattern of leptin concentrations in plasma and cerebrospinal fluid (CSF) in relation to the feeding behavior of non-lactating and lactating rats. Female rats were maintained on a controlled lighting schedule (lights on between 0600 and 1800 h) and the food intake of lactating rats was two- or threefold higher than that of non-lactating rats. In both groups, food intake was three times greater in the dark phase (P<0.01) compared with the light phase. The plasma concentrations of leptin were lower (P<0.01) in lactating rats than non-lactating rats in both light and dark phases, but there were no differences in plasma leptin levels between light and dark phases. In contrast, and in both groups, the leptin concentrations in CSF were lower (P<0.01) in the dark phase than in the light phase. Leptin levels in CSF were lower (P<0.01) in lactating rats than in non-lactating rats. We conclude that a diurnal pattern of leptin levels within the brain (but not in plasma) reflects characteristics of feeding behavior in lactating and non-lactating rats.

Animals↗
PubMed2003

Molecular marker dissection of rice (Oryza sativa L.) plant architecture under temperate and tropical climates.

Rice ( Oryza sativa L.) plants develop vertically with shoot elongation and horizontally with tillering. The purpose of this study was to identify and characterize genomic regions influencing the rice plant architecture by quantitative trait locus (QTL) analysis for the component traits: culm length (CL), panicle length (PnL), panicle number (PnN) and tiller number (TN). For this QTL analysis, 191 recombinant inbred lines (F(7)) derived from a cross of Milyang 23 (M23) and Akihikari (AK) were grown in 1995, 1996 and 1997 (May-Oct) in Joetsu, Japan (temperate climate), and in the 2000 dry season (Jan-Apr), the 2000 wet season (Jun-Oct) and the 2001 dry season in Los Baños, The Philippines (tropical climate). Results showed that rice plant architecture was influenced by 19 genomic regions categorized into five groups. In Group I, two regions (on chrs. 6 and 11) affected shoot elongation (CL and PnL) and tillering (PnN and TN) in opposite directions more significantly in Los Baños than in Joetsu. In Group II, two regions (chrs. 3 and 12) affected shoot elongation, whereas in Group III, five regions [chrs. 1 (two), 2, 3 and 9] affected only culm length (CL). Expressions of four regions of Group III were influenced by either tropical or temperate environments. In Group IV, seven regions (chrs. 1, 2, 4, 5, 6, 8 and 9) controlled panicle development (PnN or PnL), and in Group V, three regions (chrs. 1, 2 and 3) regulated tillering (PnN or TN). Characterizing these 19 genomic regions provided a detailed analysis of rice plant architecture with emphasis on the multiple effect and environmental responsive regions.

Genetic Markers↗
PubMed2003

Neural-cadherin expression associated with angiogenesis in non-small-cell lung cancer patients.

An immunohistochemical analysis for E(epithelial)-cadherin and N(neural)-cadherin expression in relation to tumour angiogenesis was performed in 150 patients with nonsmall cell lung cancer (NSCLC). In all, 71 carcinomas (47.3%) were E-cadherin-negative. Epithelial-cadherin-negative tumours had lymph node metastases significantly more frequently than E-cadherin-positive tumours (P=0.0100). On the other hand, 46 carcinomas (30.7%) were N-cadherin-positive. Regarding tumour vascularity, there was no significant correlation between E-cadherin expression and tumour vascular. In contrast, the frequency of hypervascular tumours was significantly higher for N-cadherin-positive carcinomas than for N-cadherin-negative carcinomas (P=0.0373). Regarding prognosis, the 5-year survival rate of patients with E-cadherin-negative NSCLCs was significantly lower than that of patients with E-cadherin-positive NSCLCs (P=0.0146). In contrast, of the patients with large cell carcinomas, the 5-year survival rate of patients with N-cadherin-positive tumours was significantly lower than that of patients with N-cadherin-negative tumours (P=0.0013). A multivariate analysis demonstrated that E-cadherin status (P=0.0339) and tumour vascularity (P=0.0295) were significant indicators for survival. In conclusion, E-cadherin expression and tumour vascularity are significant prognostic factors of NSCLC patients. Furthermore, N-cadherin expression is associated with tumour angiogenesis, and its expression is one of prognostic factors of patients with large cell carcinomas. Thus, N-cadherin also might play a specific role in undifferentiated large cell carcinomas.

Antigens, CD34↗
PubMed2003

Observation of B0-->pLambda(pi)(-).

We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.00)(-0.80)+/-0.56)x10(-6). Searches for B0-->pLambda(K)- and pSigma(0)pi(-) yield no significant signals and we set 90% confidence-level upper limits of B(B0-->pLambda(K)-)<8.2x10(-7) and B(B0-->pSigma(0)pi(-))<3.8x10(-6).

Journal Article↗
PubMed2003

Observation of B0 -->D0K0 and B0 -->D0K*0 decays.

We report on a search for B(0)-->D(*0)K(*0) decays based on 85 x 10(6) BB events collected with the Belle detector at KEKB. The B(0)-->D0K(0) and B(0)-->D0K(*0) decays have been observed for the first time with the branching fractions B(B(0)-->D0K(0))=(5.0(+1.3)(-1.2)+/-0.6)x10(-5) and B(B(0)-->D0K(*0))=(4.8(+1.1)(-1.0)+/-0.5)x10(-5). No significant signal has been found for the B(0)-->D(*0)K*0) and B(0)-->D(*0)K(*0) decay modes, and upper limits at 90% C.L. are presented.

Journal Article↗
PubMed2003

Observation of the decay B0-->lambda+cp.

We report the measurement of the charmed baryonic decay B(0)-->Lambda(+)(c)p with a branching fraction of (2.19(+0.56)(-0.49)+/-0.32+/-0.57)x10(-5) and a statistical significance of 5.8 sigma. The errors are statistical, systematic, and the error of the Lambda(+)(c)-->pK(-)pi(+) decay branching fraction. This is the first observation of a two-body baryonic B decay. The analysis is based on 78.2 fb(-1) of data accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) collider.

Journal Article↗
PubMed2003

Measurement of branching fractions for B-->eta(c)K(*) decays.

We report measurements of branching fractions for charged and neutral B-->eta(c)K decays where the eta(c) meson is reconstructed in the K(0)(S)K+/-pi(-/+), K+K-pi(0), K(*0)K-pi(+), and pp; decay channels. The neutral B0 channel is a CP eigenstate and can be used to measure the CP violation parameter sin(2phi(1). We also report the first observation of the B0-->eta(c)K(*0) mode. The results are based on an analysis of 29.1 fb(-1) of data collected by the Belle detector at KEKB.

Journal Article↗
PubMed2003

Measurement of the electroweak penguin process B-->X(s)l+l-.

We report the first measurement of the branching fraction for the inclusive decay B-->X(s)l(+)l(-), where l is either an electron or a muon, and X(s) is a hadronic recoil system that contains an s quark. We analyzed a data sample of 65.4 x 10(6) B meson pairs collected with the Belle detector at the KEKB e(+)e(-) asymmetric-energy collider. We find B(B-->X(s)l(+)l(-))=[6.1 +/-1.4(stat) +1.4-1.1(syst)] x 10(-6) for dilepton masses greater than 0.2 GeV/c(2).

Journal Article↗
PubMed2003

Prions prevent brain damage after experimental brain injury: a preliminary report.

The physiological function of the normal cellular form of prion protein (PrPC) is not yet fully understood. In the current study we used prion protein gene knock-out mice (Prnp-/-) to assess the role of PrPC in traumatic brain injury. Prnp+/- and Prnp-/- mice were subjected to weight-drop contusional brain injury over the left parietal cortex. Prnp-/- mice manifested a significantly larger lesion volume and worse neuromotor scores than did their Prnp+/- littermates. IgG immunostaining revealed that in Prnp-/- mice the breakdown in the blood-brain barrier (BBB) was more extensive at 1 month after brain injury. Our results are in agreement with previous in vitro findings of the neuroprotective role of PrPC and further support the hypothesis that functional loss of PrPC plays a pathogenic role in prion diseases. We also suggest that PrPC modulates BBB function.

Animals↗
PubMed2003

The glutamate AMPA receptor antagonist, YM872, attenuates regional cerebral edema and IgG immunoreactivity following experimental brain injury in rats.

We previously reported the neuroprotective effects of the glutamate AMPA receptor antagonist YM872 on neurobehavioral motor function and cortical tissue loss (lesion volume) in a brain-injured rat model. Here we examined its effect on brain edema and the breakdown of the blood-brain barrier (BBB). Rats subjected to severe right lateral (parasagittal) fluid-percussion brain injury or sham injury received a 4-hr intravenous infusion of YM872 (20 mg/kg/ hr, 20 mg/3 ml) or normal saline starting at 15 min post-injury. At 48 hr we removed their brains and evaluated the cerebral regional edema by the wet weight/dry weight method. Another group of rats was transcardially fixed with 10% formalin at 2 weeks after injury. Serial brain sections were immunostained for endogenous IgG and the extent and intensity of staining were evaluated. The administration of YM872 resulted in a significant reduction in regional cerebral edema in the injured parietal cortex and a markedly reduced area of IgG immunoreactivy in the injured cortex. Our results indicate that the post-traumatic administration of YM872 may be neuroprotective by reducing BBB breakdown and regional cerebral edema.

Animals↗