Biomedical subjects

S Sato

Publications and source records attributed to S Sato.

At least 19 recordsLinked to original sources

PubMed2007

A comparison of root surface instrumentation using two piezoelectric ultrasonic scalers and a hand scaler in vivo.

BACKGROUND AND OBJECTIVE: This study compared the effectiveness of two piezoelectric ultrasonic scalers and a hand scaler for subgingival scaling and root planing in vivo. MATERIAL AND METHODS: Fifteen patients with advanced periodontal disease and with teeth scheduled for extraction were selected for this study. Three experimental groups of 10 teeth each were treated with one of two piezoelectric ultrasonic scalers [Vector scaler and Enac scaler] or with a hand scaler. Instrumentation was continued until the root surface felt hard and smooth to an explorer tip. The root surface characteristics after instrumentation were examined using scanning electron microscopy, and the amount of remaining calculus, roughness and loss of tooth substance were estimated using the remaining calculus index and roughness loss of tooth substance index. RESULTS: The remaining calculus index did not differ significantly among the three groups. The roughness loss of tooth substance index was significantly lower for the Vector scaler and Enac scaler groups than for the hand scaler group and also differed significantly between the Vector scaler and Enac scaler groups. CONCLUSION: This study suggests that the Vector scaler produces a smooth root surface with minimal loss of tooth substance. It is a reasonable choice for gentle periodontal maintenance treatment.

Dental Calculus↗

PubMed2006

Prediction of visceral fat area in Japanese adults: proposal of prediction method applicable in a field setting.

OBJECTIVE: This study aimed to develop a prediction equation for the visceral fat area at the umbilical level (VFA(L4-5)) in Japanese adults, using internal fat mass (IFM) estimated from a few anthropometric variables. METHODS: Subjects were 112 adults aged from 25 to 82 years (body mass index (BMI)=24.2+/-3.1 kg/m(2), ranged from 15.7 to 31.2 kg/m(2)). Another 60 adults aged from 21 to 71 years were recruited for the crossvalidation group (BMI=24.5+/-4.0 kg/m(2), ranged from 17.1 to 34.6 kg/m(2)). We examined (1) the prediction of IFM based on a small number of skinfold thicknesses; (2) the prediction of VFA(L4-5) using IFM and (3) the application of bioelectrical impedance analysis (BIA) measurement. VFA(L4-5) was measured by computed tomography (reference value). Total fat mass was measured by dual-energy X-ray absorptiometry (DXA) and single-frequency BIA with 8-point tactile electrodes. RESULTS: Three skinfolds at the abdomen, side chest and suprailiac were selected to estimate IFM. From IFM estimated using these three skinfolds, waist-to-hip ratio (WHR), sex and age, about 75% of the variance of VFA(L4-5) could be explained (Eq(VFA)1: R=863, R(2)=0.745, standard error of estimate (s.e.e.)=20.483 cm(2)). When substituting IFM based on BIA measurement (IFM(BIA)) into Eq(VFA)1, there were no significant mean differences from the reference in both equations, and high correlations were found (r=0.860, s.e.e.=20.902 cm(2)), although a significant mean difference in total fat mass was found between DXA and BIA measurements. The prediction equation using IFM(BIA) (Eq(VFA)2) could have prediction accuracy comparable with that of Eq(VFA)1 (Eq(VFA)2: R=879, R(2)=0.773, s.e.e.=20.324 cm(2)). Furthermore, when applying these equations to the crossvalidation group, there were cross-validity in both equations. CONCLUSION: This study proposed a prediction equation for VFA(L4-5) from WHR and IFM based on three skinfolds, and the validity of BIA measurement in Japanese adults. We can propose the procedure for a field setting.

Absorptiometry, Photon↗

PubMed2006

CSF tau protein: a new prognostic marker for Guillain-Barré syndrome.

We measured the CSF tau protein levels in 26 patients with Guillain-Barré syndrome. The levels of the poor outcome group (Hughes grade at 6 months was between II and VI, n = 6) were higher than those of the good outcome group (0 or I, n = 20) (p < 0.0005). The higher levels of CSF tau may reflect axonal degeneration and could predict a poor clinical outcome in Guillain-Barré syndrome.

Adult↗

PubMed2006

Primary germinoma arising from the midbrain.

A 29-year-old man presented with diplopia, dysarthria, anisocoria, oculomotor nerve paralysis, abducens nerve paralysis, right facial palsy, and spastic hemiparetic gait. Magnetic resonance imaging (MRI) showed a homogenously enhanced mass in the midbrain. MRI-guided stereotactic biopsy was performed, and the histologic diagnosis was pure germinoma. The tumor disappeared after chemotherapy and radiotherapy. Germinoma should be included in the differential diagnosis of midbrain lesions in young adults. MRI-guided stereotactic biopsy provided a helpful diagnostic clue in a patient with a midbrain lesion.

Adult↗

PubMed2006

Molecular cloning and gene expression of a fibrillarin homolog of tobacco BY-2 cells.

Fibrillarin is known to play an important role in precursor ribosomal RNA processing and ribosome assembly. The present study describes a fibrillarin homolog gene isolated from tobacco BY-2 cells and its expression during the cell cycle. The cDNA for a fibrillarin homolog, named NtFib1, was first cloned in Nicotiana tabacum with degenerate primers. It encodes 314 amino acids and the deduced amino acid sequence has some highly conserved functional domains, such as the glycine and arginine-rich (GAR) domain for nucleolar localization and the RNA-binding motif. The C-terminal region is highly conserved and has 7 beta-sheets and 7 alpha-helices which are peculiar to fibrillarin. Thus, it is suggested that the fibrillarin homolog of this plant species functions in the same way as the fibrillarin already known from human and yeast cells. Northern blot analysis of BY-2 cells synchronized with aphidicolin or a combination of aphidicolin and propyzamide showed that the histone H4 gene was specifically expressed in the S phase but NtFib1 mRNA remained at high levels during the cell cycle. Examination of the localization of NtFib1 protein tagged with green-fluorescent protein (GFP) suggested that some persisting in the mitotic apparatus was eventually incorporated into reconstructed nucleoli in late telophase. Newly synthesized GFP-tagged NtFib1 protein in the cytoplasm was added to the recycled protein in early mitosis. Highly concentrated actinomycin D completely inhibited the transcription of genes coding for rRNA (rDNA) but did not significantly suppress the amount of either NtFib1 mRNA or protein, although the NtFib1 protein was reversibly dislocated from nucleoli. Although hypoxic shock completely prohibited rDNA transcription, NtFib1 mRNA remained at the same level as in the control experiment, even after the 4 h treatment. These results indicate that the transcription of NtFib1 mRNA is not related to rDNA transcription and NtFib1 mRNA is resistant to disrupting factors during the cell cycle.

Amino Acid Sequence↗

PubMed2006

Comparative study of cellular structures implicated in gravisensing in statocytes of primary and lateral roots of Vigna angularis.

The cellular structures of statocytes implicated in gravisensing in primary and lateral roots of Vigna angularis were compared. The statocytes of lateral roots already had small amyloplasts immediately after they emerged from the primary root. Although these amyloplasts sedimented, the lateral roots showed much weaker gravitropism than primary roots, at least until they reached a length of about 30 mm. The nuclei were usually positioned in the upper end of the statocytes in both types of roots. Electron microscopic surveys showed that many tubular elements of endoplasmic reticulum (ER) were frequently localized in the lower end of the statocyte and they sometimes diverged or curved, suggesting that the ER forms a large reticulate complex. It is worth noting that statocytes with a large ER complex were found much more frequently in primary roots than in lateral roots. The amyloplasts were not always settled on this complex but were very frequently under it, especially in the primary roots. In lateral roots, they were usually localized under the ER complex when they were present. Thus, it is suggested that the differential development and organization of the amyloplast-ER complex system is involved in the differential gravitropism of the two types of roots.

Endoplasmic Reticulum↗

PubMed2006

Surgical resection of tumors located in subcortex of language area.

OBJECT: Although functional mapping facilitates the planning of surgery in and around eloquent areas, the resection of tumors adjacent to language areas remains challenging. In this report, we took notice that the language areas (Broca's and Wernicke's) present at the perisylvian fissure. We posit that if there is non-essential language area on the inner surface of the Sylvian fissure, safe tumor resection may be possible even if the tumor is located under the language cortex. METHODS: The study population consisted of 5 patients with intrinsic brain tumors (frontal glioma, n = 3; temporal cavernous angioma, n = 1; primary malignant central nervous system lymphoma, n = 1) located in the perisylvian subcortex, in the language-dominant hemisphere. All patients underwent awake surgery and we performed intra-operative bipolar cortical functional language mapping. When the tumor was located under the language area, the Sylvian fissure was opened and the inner surface of the opercular cortex was exposed with the patient asleep, and additional functional mapping of that cortex was performed. This enabled us to remove the tumor from the non-functioning cortex. In our series, 4 of 5 patients had not language function on the inner surface of the operculum. Only one patient, a 52-year-old man with frontal glioblastoma (Case 3) had language function on the inner surface of the frontal operculum. CONCLUSION: We suggest that even perisylvian tumors located in the subcortex of the language area may be resectable via the nonfunctioning intrasylvian cortex by a transopercular approach without resultant language dysfunction.

Adult↗

PubMed2006

Systematic review and meta-analysis: importance of CagA status for successful eradication of Helicobacter pylori infection.

BACKGROUND: Some, but not all studies have provided evidence that the CagA status of Helicobacter pylori strains is a predictive factor for the outcome of eradication therapy. AIM: To clarify the association between CagA status and eradication outcome. METHODS: We included studies reporting the numbers of successful and failed cases in H. pylori-eradication therapy according to the CagA status. Fourteen studies (1529 patients) were included of 325 articles identified in the search. The pooled risk ratio for H. pylori-eradication failure in CagA-negative relative to CagA-positive strains and the pooled risk difference in eradication success between the two groups were used as summary statistics. Meta-regression was used for examining the source of heterogeneity. RESULTS: The summary risk ratio for eradication failure in CagA-negative relative to CagA-positive was 2.0 (95% CI: 1.6-2.4, P < 0.001), corresponding with the summary risk difference for eradication success between the groups of 11% (95% CI: 3-19%, P = 0.011). Meta-regression analysis demonstrated that usage of polymerase chain reaction examination for CagA status and a high proportion of non-ulcer dyspepsia patients were factors for heterogeneity among studies. CONCLUSIONS: Our meta-analysis confirmed the importance of the presence of CagA as a predictor for successful eradication of H. pylori.

Antigens, Bacterial↗

PubMed2006

Identification of a novel autoantibody reactive with 155 and 140 kDa nuclear proteins in patients with dermatomyositis: an association with malignancy.

OBJECTIVE: Myositis-specific autoantibodies (MSAs) are a useful tool in diagnosis, defining clinical subsets and predicting prognosis of dermatomyositis (DM) and polymyositis (PM). In this study, we identified a novel MSA reactive with 155 and 140 kDa nuclear proteins [anti-155/140 antibody (Ab)] and determined the clinical feature of DM patients positive for this autoantibody (autoAb). METHODS: Sera from 52 Japanese patients with DM, 9 with PM, 48 with systemic lupus erythematosus (SLE), 126 with systemic sclerosis and 18 with idiopathic interstitial pneumonia were examined by immunoprecipitation assays. Positive sera were further characterized by immunodepletion and immunofluorescence staining. RESULTS: Seven of the 52 (13%) Japanese patients with DM immunoprecipitated 155 and 140 kDa proteins from 35S-labelled K562 leukaemia cell extract. No patients with SLE, systemic sclerosis or idiopathic interstitial pneumonia as well as healthy controls were positive for this autoAb. Patients with anti-155/140 Ab developed heliotrope rash, Gottron's papules or sign and flagellate erythema significantly more frequently than those negative. Notably, internal malignancy was found at significantly higher frequency in those positive than those negative (71 vs 11%; P < 0.005). In contrast, none of these patients positive for this autoAb had interstitial lung disease. CONCLUSIONS: This novel MSA is associated with cancer-associated DM and may serve as a diagnostic serological marker for this specific subset.

Adult↗

PubMed2006

Landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, does not alter the electroencephalographic effect of isoflurane in swine model.

BACKGROUND: beta-Adrenergic blocking agents may interact with anaesthetics, and several studies suggest that beta-blockers attenuate electroencephalographic responses during general anaesthesia. We have investigated the influence of landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, on the electroencephalographic effect of isoflurane in pigs. METHODS: Ten swine were anaesthetized through inhalation of 2% isoflurane. The inhalational concentration was then decreased to 0.5% and maintained for 25 min, before being returned to 2% and maintained for a further 25 min (control period). After control measurements, infusion of landiolol (at 0.125 mg kg(-1) min(-1) for 1 min, and then at 0.04 mg kg(-1) min(-1)) was started. After a 20 min stabilization period, the inhalational concentration was varied as in the control period (40 gamma landiolol). Finally, infusion of landiolol was increased from 0.04 to 0.2 mg kg(-1) min(-1), and after a 20 min stabilization period, the inhalational concentration was again varied as in the control period (200 gamma landiolol). End-tidal isoflurane concentrations and spectral edge frequencies were recorded throughout the study. Analysis of the pharmacodynamics was performed using a sigmoidal inhibitory maximal effect model for spectral edge frequency vs effect-site concentration. RESULTS: There were no significant differences in the effect of isoflurane among the conditions used. Landiolol did not shift the concentration-effect relationship [the effect-site concentration that produced 50% of the maximal effect was 1.35 (0.17)% under control conditions, 1.30 (0.12)% at 40 gamma landiolol, and 1.38 (0.30)% at 200 gamma landiolol]. CONCLUSION: Landiolol does not alter the electroencephalographic effect of isoflurane.

Adrenergic beta-1 Receptor Antagonists↗

PubMed2006

Clinical and MRI features of Japanese patients with multiple sclerosis positive for NMO-IgG.

This study investigates the relation between the serological status of NMO (neuromyelitis optica)-IgG and the clinical and MRI features in Japanese patients with multiple sclerosis. Serum NMO-IgG was tested in 35 Japanese patients diagnosed with multiple sclerosis, including 19 with the optic-spinal form of multiple sclerosis (OSMS), three with the spinal form of multiple sclerosis (SMS), and 13 with the conventional form of multiple sclerosis (CMS), which affects the brain. NMO-IgG was detected in 14 patients, 12 with OSMS and 2 with CMS. In these patients, longitudinally extensive (> 3 vertebral segments) spinal cord lesions (93% v 57%) and permanent, complete blindness (no perception of light) in at least one eye (50% v 0%) were the noticeable features as compared with NMO-IgG-negative OSMS. The two patients having CMS with NMO-IgG had unusual brain lesions, but in other respects had features suggesting OSMS. NMO-IgG was detected in more than half the number of patients with OSMS and in some patients with CMS. This newly discovered serum autoantibody was markedly associated with longitudinally extensive spinal cord lesions and with complete blindness, suggesting severe optic-spinal disease.

Adult↗

PubMed2006

Moderate increase of mean daily temperature adversely affects fruit set of Lycopersicon esculentum by disrupting specific physiological processes in male reproductive development.

BACKGROUND AND AIMS: Global warming is gaining significance as a threat to natural and managed ecosystems since temperature is one of the major environmental factors affecting plant productivity. Hence, the effects of moderate temperature increase on the growth and development of the tomato plant (Lycopersicon esculentum) were investigated. METHODS: Plants were grown at 32/26 degrees C as a moderately elevated temperature stress (METS) treatment or at 28/22 degrees C (day/night temperatures) as a control with natural light conditions. Vegetative growth and reproductive development as well as sugar content and metabolism, proline content and translocation in the androecium were investigated. KEY RESULTS: METS did not cause a significant change in biomass, the number of flowers, or the number of pollen grains produced, but there was a significant decrease in the number of fruit set, pollen viability and the number of pollen grains released. Glucose and fructose contents in the androecium (i.e. all stamens from one flower) were generally higher in the control than METS, but sucrose was higher in METS. Coincidently, the mRNA transcript abundance of acid invertase in the androecium was decreased by METS. Proline contents in the androecium were almost the same in the control and METS, while the mRNA transcript level of proline transporter 1, which expresses specifically at the surface of microspores, was significantly decreased by METS. CONCLUSIONS: The research indicated that failure of tomato fruit set under a moderately increased temperature above optimal is due to the disruption of sugar metabolism and proline translocation during the narrow window of male reproductive development.

Amino Acid Transport Systems, Neutral↗

PubMed2006

Serum levels of 8-isoprostane, a marker of oxidative stress, are elevated in patients with systemic sclerosis.

OBJECTIVE: To determine serum levels and clinical correlation of 8-isoprostane, which is produced in vivo through free radical-catalysed peroxidation of arachidonic acid and reflects oxidative stress, in patients with systemic sclerosis (SSc). METHODS: Serum 8-isoprostane levels from 32 patients with diffuse cutaneous SSc (dSSc) and 25 patients with limited cutaneous SSc (lSSc) were examined by enzyme-linked immunosorbent assay. RESULTS: Serum 8-isoprostane levels were elevated in dSSc and lSSc patients by 75-fold compared with normal controls (n=32). Serum 8-isoprostane levels correlated negatively with pulmonary function, such as percentage vital capacity and diffusion capacity for carbon monoxide, and correlated positively with renal vascular damage determined by colour flow Doppler ultrasonography. Serum 8-isoprostane levels also correlated positively with serum levels of IgG and anti-agalactosyl IgG autoantibody. CONCLUSION: Increased 8-isoprostane levels correlated with the severity of pulmonary fibrosis, the extent of renal vascular damage and immunological abnormalities in SSc, suggesting that enhanced oxidative stress is related to the development of SSc.

Adult↗

PubMed2006

Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing.

In the favoured core-accretion model of formation of planetary systems, solid planetesimals accumulate to build up planetary cores, which then accrete nebular gas if they are sufficiently massive. Around M-dwarf stars (the most common stars in our Galaxy), this model favours the formation of Earth-mass (M(o)) to Neptune-mass planets with orbital radii of 1 to 10 astronomical units (au), which is consistent with the small number of gas giant planets known to orbit M-dwarf host stars. More than 170 extrasolar planets have been discovered with a wide range of masses and orbital periods, but planets of Neptune's mass or less have not hitherto been detected at separations of more than 0.15 au from normal stars. Here we report the discovery of a 5.5(+5.5)(-2.7) M(o) planetary companion at a separation of 2.6+1.5-0.6 au from a 0.22+0.21-0.11 M(o) M-dwarf star, where M(o) refers to a solar mass. (We propose to name it OGLE-2005-BLG-390Lb, indicating a planetary mass companion to the lens star of the microlensing event.) The mass is lower than that of GJ876d (ref. 5), although the error bars overlap. Our detection suggests that such cool, sub-Neptune-mass planets may be more common than gas giant planets, as predicted by the core accretion theory.

Journal Article↗

PubMed2006

Antibacterial activity of plant extracts from azuki beans (Vigna angularis) in vitro.

This study was undertaken to examine the antimicrobial property of azuki beans (Vigna angularis). The water extracts of green, black and red colored azuki beans showed antibacterial effects against Staphylococcus aureus, Aeromonas hydrophila and Vibrio parahaemolyticus. In contrast, the extract of white azuki beans showed no inhibition towards any of the microorganisms examined. The extracts of colored azuki beans contained larger amounts of polyphenols including proanthocyanidins than the extracts of white azuki beans. The counts of S. aureus cells, inoculated in the medium containing the extracts of colored azuki beans, were significantly reduced in comparison with those of control and white azuki beans after 24 h (p < 0.05). These results suggest that polyphenols including proanthocyanidins in colored azuki beans may be responsible for their antibacterial activity.

Anti-Bacterial Agents↗

PubMed2006

Molecular mechanisms of nigral neurodegeneration in Park2 and regulation of parkin protein by other proteins.

Most of the patients with Parkinson's disease (PD) are sporadic. However, Since identification of monogenic forms of PD, the contribution of genetic factors to the pathogenesis of sporadic PD is proposed as one of major risk factors. Indeed, this is supported by the demonstration of the high concordance in twins, increased risk among relatives of PD patients in case control and family studies. Thus, the functional analysis for the gene products for familial PD provides us a good hint to elucidate the pathogenesis of nigral degeneration. For example, although alpha-synuclein is involved in a rare dominant form of familial PD with dopa responsive parkinsonian features, this molecule is a major component of and Lewy bodies (LBs). In contrast, Park2 (parkin-related disease) is the most frequent form among patients with young-onset PD. However, Park2 brains generally lack the formation of LBs. In the other word, parkin responsible for Park2 is essential for the formation of LBs. Thus, both alpha-synuclein and parkin are speculated to share a common pathway. Here, we reviewed the parkin function and molecular mechanisms of Park2.

Gene Expression Regulation↗

PubMed2006

Role of antinuclear antibodies in experimental and clinical liver transplantation.

OBJECTIVE: We recently reported that autoreactive antibodies (Abs) against nuclear histone H1 was transiently induced at an early phase after orthotopic liver transplantation (OLT) in a tolerogenic rat OLT model and possessed immunosuppressive activity. It was also reported that nuclear antigen, high-mobility group box 1 (HMGB1) protein was one of the initiators of the immune reaction. The present study sought to evaluate the role of antinuclear Abs in experimental and clinical liver transplantation. MATERIALS AND METHODS: We prepared 3 animal models: natural tolerance model (DA liver into PVG); acute rejection model (DA liver into LEW); and drug-induced tolerance model (acute rejection model + cyclosporine [CsA]). In addition, we examined clinical samples, including 1 drug-free patient, to measure the antihistone H1/HMGB1 titers at various times after OLT. RESULTS: In a natural tolerance model, antihistone H1 and HMGB1 Ab was induced during the rejection and the tolerance induction phases, respectively. Those Ab responses were also confirmed in a drug-induced tolerance model, whereas no such responses were shown in an acute rejection model. In our clinical drug-free patient, antihistone H1/HMGB1 titer was significantly higher after cessation of CsA than that in healthy volunteers. CONCLUSIONS: Antinuclear Ab is actively expressed in accordance with overcoming rejection episodes with subsequent tolerance induction in both a natural tolerance model and a drug-induced tolerance model. We also observed a similar tendency in our clinical drug-free patient. These results suggested that antinuclear Abs may be useful markers to determine the timing to withdraw immunosuppressants.

Animals↗

PubMed2006

Histone H1 vaccine therapy for overcoming acute rejection in experimental organ transplantation.

OBJECTIVE: In a rat tolerogenic orthotopic liver transplantation (OLT) model, the recipient serum (post-OLT serum) shows strong immunosuppressive activity. In our previous reports, we suggested that autoreactive antibody (Ab) against histone H1 is a major immunosuppressive factor in this serum. The present study sought to determine whether up-regulation of anti-histone H1 Ab by histone H1 vaccination led to tolerance. MATERIALS AND METHODS: Using mixed lymphocyte reactions (MLR) and heterotopic heart transplantations (HHT), the alloreactive T-cell responses and allograft survivals of histone H1-immunized rats were compared with those of control rats. Cytokine and cellular profiles were determined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. RESULTS: The alloreactive T-cell response of histone H1-immunized rats was significantly lower than that of control rats, although there was no difference in nonspecific T-cell activation between the 2 groups. The allograft survival of histone H1-immunized rats was significantly prolonged after HHT. The major histocompatibility complex (MHC) class II and CD25 molecules of histone H1-immunized rats were significantly down-regulated compared with those of control rats. Moreover, the serum cytokine profile was modified by the immunization with histone H1. CONCLUSIONS: These results suggest that histone H1 vaccination of transplant recipients leads to the production of immunosuppressive factors and the modification of cytokine/cellular profiles.

Animals↗