Biomedical subjects

T Sato

Publications and source records attributed to T Sato.

At least 73 records · Page 4Linked to original sources

PubMed2005

Portal flow into the liver through veins at the site of biliary-enteric anastomosis.

The aim of this study was to establish the role played by jejunal veins in hepatopetal flow after biliary-enteric anastomosis and to evaluate the helical CT features of hepatopetal flow through the anastomosis. We retrospectively analyzed helical CT images of the liver in 31 patients with biliary-enteric anastomosis who underwent hepatic angiography with (n=13) or without (n=18) CT arterial portography within 2 weeks of the CT examination during the last 4 years. Arterial portography showed hepatopetal flow through small vessels located (communicating veins) between the elevated jejunal veins and the intrahepatic portal branches in two (9%) of 22 patients with a normal portal system. Helical CT showed focal parenchymal enhancement around the anastomosis in these two patients. All nine patients with extrahepatic portal vein occlusion (100%) had hepatopetal flow through the anastomosis, and four of the nine had decreased portal flow. CT revealed small communicating veins in two of these four patients. In five patients with normal portal perfusion despite extrahepatic portal vein occlusion, CT detected dilated communicating veins and elevated jejunal veins. The presence of communicating veins and/or focal parenchymal enhancement around the anastomosis indicates hepatopetal flow through the elevated jejunal veins.

Adult↗

PubMed2005

Angle-resolved photoemission spectroscopy of the antiferromagnetic superconductor Nd1.87Ce0.13CuO4: anisotropic spin-correlation gap, pseudogap, and the induced quasiparticle mass enhancement.

We performed high-resolution angle-resolved photoemission spectroscopy on Nd1.87Ce0.13CuO4, which is located at the boundary of the antiferromagnetic (AF) and the superconducting phase. We observed that the quasiparticle (QP) effective mass around (pi,0) is strongly enhanced due to the opening of the AF gap. The QP mass and the AF gap are found to be anisotropic, with the largest value near the intersecting point of the Fermi surface and the AF zone boundary. In addition, we observed that the QP peak disappears around the Néel temperature (TN) while the AF pseudogap is gradually filled up at much higher temperatures, possibly due to the short-range AF correlation.

Journal Article↗

PubMed2005

Health risks of heavy metals to the general public in Tianjin, China via consumption of vegetables and fish.

Consumption of vegetables and fish contaminated with the heavy metals Cu, Zn, Pb, Cd, Hg, and Cr is the most likely route for human exposure in Tianjin, China. Health risks associated with these heavy metals were assessed based on the target hazard quotients (THQs), which can be derived from concentrations of heavy metals in vegetables and fish consumed in four districts (Dong Li, Xi Qing, Jin Nan, and Bei Chen) and the urban area of Tianjin, China. Individual metal THQ (<1) values indicate the relative absence of health risks associated with intake of a single heavy metal through consumption of either contaminated vegetables or fish only. However, consumption of both vegetables and fish would lead to potential health risks especially for children, since individual THQs for vegetables and fish would sum up to almost 1. If individual THQs resulting from crops consumption are considered, the health risks would be greater for children since the THQ values will always be >1. Risk contribution from Cr is minimal compared to the other elements. Hg is the major risk contributor for children in Bei Chen since the THQ contribution amounts to about 45% of the total THQ values due to vegetables and fish consumption. The health risk to adults in Ding Li is ascribed mainly to the intake of Cd by vegetables and fish consumption, which contributes a substantial fraction to the total THQ (about 51%).

Adult↗

PubMed2005

Heme oxygenase-1 inhibits cigarette smoke-induced increase in the tracheal mucosal permeability in guinea pigs in vivo.

OBJECTIVE: To examine whether heme oxygenase (HO)-1 inhibits cigarette smoke (CS)-induced increase in the airway mucosal permeability. METHODS: Mucosal permeability was quantified by monitoring the rate of appearance in the circulation of horseradish peroxidase that had been instilled into the isolated tracheal segment in guinea pigs in vivo, after exposure to CS or room air. RESULTS: Exposure to 10 puffs of CS did not increase the tracheal mucosal permeability but did increase the permeability after pretreatment with zinc protoporphyrin, a competitive inhibitor of HO-1. Moreover, pretreatment with hemin, a potent inducer of HO-1, inhibited the increase in the permeability of the tracheal mucosa induced by 20 puffs of CS exposure. CONCLUSION: It is concluded that HO-1 has an important role in suppressing the increase in the mucosal permeability induced by CS in guinea pig trachea.

Animals↗

PubMed2005

Simulations of an accelerator-based shielding experiment using the particle and heavy-ion transport code system PHITS.

In order to estimate the biological effects of HZE particles, an accurate knowledge of the physics of interaction of HZE particles is necessary. Since the heavy ion transport problem is a complex one, there is a need for both experimental and theoretical studies to develop accurate transport models. RIST and JAERI (Japan), GSI (Germany) and Chalmers (Sweden) are therefore currently developing and bench marking the General-Purpose Particle and Heavy-Ion Transport code System (PHITS), which is based on the NMTC and MCNP for nucleon/meson and neutron transport respectively, and the JAM hadron cascade model. PHITS uses JAERI Quantum Molecular Dynamics (JQMD) and the Generalized Evaporation Model (GEM) for calculations of fission and evaporation processes, a model developed at NASA Langley for calculation of total reaction cross sections, and the SPAR model for stopping power calculations. The future development of PHITS includes better parameterization in the JQMD model used for the nucleus-nucleus reactions, and improvement of the models used for calculating total reaction cross sections, and addition of routines for calculating elastic scattering of heavy ions, and inclusion of radioactivity and burn up processes. As a part of an extensive bench marking of PHITS, we have compared energy spectra of secondary neutrons created by reactions of HZE particles with different targets, with thicknesses ranging from <1 to 200 cm. We have also compared simulated and measured spatial, fluence and depth-dose distributions from different high energy heavy ion reactions. In this paper, we report simulations of an accelerator-based shielding experiment, in which a beam of 1 GeV/n Fe-ions has passed through thin slabs of polyethylene, Al, and Pb at an acceptance angle up to 4 degrees.

Aluminum↗

PubMed2005

Minimally invasive plate osteosynthesis for comminuted fractures of the metaphysis of the radius.

Five comminuted and displaced fractures of the distal metaphysis of the radius were treated by a technique of minimally invasive plate osteosynthesis (MIPO) with the aim of minimizing soft tissue damage and devascularization of the fracture fragments. This technique used the small AO T-shaped locking compression plate (AO LCP T-plate) and left the pronator quadratus intact. Radial inclination, palmar tilt, and ulnar variance were restored without loss of reduction in all five cases and the fractures healed at an average of 10 weeks, with good to excellent clinical outcomes.

Adult↗

PubMed2005

Deoxyspergualin prophylaxis with tacrolimus further improves long-term graft survival in living-related renal-transplant recipients transfused with donor-specific blood.

BACKGROUND: We examined whether deoxyspergualin (DSG) prophylaxis in combination with cyclosporine (CsA)- or tacrolimus (Tac)-based immunosuppression augments the effect of donor-specific blood transfusions (DSTs) to improve long-term survival of living-related renal-transplants. METHODS: From May 1985 to January 1998, 176 patients received DST from one-haplotype-identical donors prior to kidney transplantation. Group A (n = 64, 1985 to 1989) received CsA, prednisolone (PSL), antilymphocyte globulin (ALG), and azathioprine (AZA). Group B (n = 89, 1989 to 1996) received CsA, PSL, ALG, and DSG. Group C (n = 23, 1996 to 1998) received Tac, PSL, ALG, and DSG, with DSG followed by AZA. Rejection episodes were classified as acute rejection (AR, within the first 3 months) or late acute rejection (LAR, from 4 months to 1 year). RESULTS: Five-year graft survivals were 73.4%, 88.8%, and 91.3% for groups A, B, and C, respectively. The incidence of AR was 34%, 30%, and 13%, and that of LAR was 23%, 26%, and 30% for groups A, B, and C, respectively. There was no significant difference in the incidence of AR or LAR among the three groups. However, an elevated serum creatinine (sCr) > or =1 mg/dL was observed in 73%, 15%, and 0% of patients during AR, and in 53%, 30%, and 14% during LAR for groups A, B, and C, respectively. These results suggest that the severity of AR or LAR was lowest among group C, contributing to the improved long-term graft survival in these patients. CONCLUSIONS: DSG prophylaxis with Tac-based immunosuppression further improves long-term graft survival among living-related renal-transplant recipients treated with DST by decreasing the severity of acute rejection episodes.

Acute Disease↗

PubMed2005

Irritable psychomotor elation in depressed inpatients: a factor validation of mixed depression.

BACKGROUND: Early authors described hypomanic symptoms as mixed features in depressive episode, but this syndrome has not been sufficiently explored in previous studies. METHODS: 958 consecutive depressed patients were assessed by using a standardized method in terms of 43 psychiatric symptoms at hospitalization. RESULTS: A principal component analysis, followed by varimax rotation, extracted six interpretable factors: typical vegetative symptoms, depressive retardation/loss of feeling, hypomanic syndrome, anxiety, psychosis, and depressive mood/hopelessness. The extracted factor structure was relatively stable among several patient groups. There was no evidence that the hypomanic factor was exaggerated by antidepressant pretreatments before hospitalization. Bipolar diagnoses were associated with higher scores on depressive retardation and hypomanic symptoms, and a lower score on anxiety. LIMITATIONS: Psychiatric syndromes and their interrelationships, found in the present study, may be strongly influenced by the rating instrument used. The sample of this study was depressed inpatients. The results should not be generalized for depressed outpatients or epidemiological depressed populations. CONCLUSIONS: Hypomanic symptoms, as characterized by the flight of ideas, racing thought, increased drive, excessive social contact, irritability, and aggression are a salient syndrome in acutely ill depressed patients, lending support to the factor validity of mixed depression. The symptoms may not be related to pretreatments with antidepressants, or comorbidity of substance abuse, suggesting that they reflect various natural phenomenological manifestations of depressive episodes. Anxiety is unlikely to play a major role in the core phenomenological features of mixed depression. Hypomanic symptoms during a depressive episode were more represented in bipolar disorders, which may serve for further clarifications of latent bipolarity in unipolar depression, and prediction of switch into maniform states under biological depression treatments.

Adult↗

PubMed2005

Significance of eosinophilia after stem cell transplantation as a possible prognostic marker for favorable outcome.

Although eosinophilia after stem cell transplantation (SCT) has been addressed in recent reports, the significance of eosinophilia in disease outcome after SCT has not been well studied. In this study, we investigate the frequency of eosinophilia after SCT to determine its prognostic value. The subjects were 113 patients with malignant or nonmalignant diseases who underwent SCT treatment. In these patients, eosinophilia was detected in 44 cases (38.9%), on average 67.5 days after transplantation, and the mean maximum absolute eosinophil count was 840.5 x 10(6)/l. To study the basis of eosinophilia after SCT, various serum cytokine levels during SCT in patients both with and without eosinophilia were analyzed. Statistical analysis indicated that the overall patient survival rates improved in those with eosinophilia compared to those without eosinophilia (88.7 vs 43.0%, P=0.0034). In particular, in patients with malignant diseases, those with eosinophilia showed a higher event-free survival (81.1 vs 44.6%, P=0.0025) and a lower relapse rate (16.0 vs 43.0%, P=0.0287) than those without eosinophilia. In conclusion, we propose that eosinophilia after SCT could be a useful prognostic marker for determining favorable outcomes in patients with malignant diseases. The reasons for this good prognosis in SCT patients with eosinophilia are discussed.

Adolescent↗

PubMed2005

Association between arterial stiffness and platelet activation.

Increased arterial stiffness is strongly associated with atherosclerosis, while platelet activation is an important trigger of thrombotic events in patients with atherosclerosis. However, little is known about the effect of arterial stiffness on platelet activation. We therefore investigated the association between arterial stiffness and platelet activation in 38 normal volunteers (20 men and 18 women) aged 23-77 years (mean = 49 +/- 15 years). Arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (ba-PWV) and heart-brachial PWV (hb-PWV). Flow cytometric analyses were performed to evaluate platelet activation by measuring surface expression of P-selectin and platelet-neutrophil complexes (PNC) before and after activation by ADP. We also calculated the difference between basal and stimulated states of P-selectin and PNC to assess platelet activation reserve. PWVs were significantly correlated with age and BP (r = 0.60-0.81). For platelet activation and activation reserve, correlations with age were less strong but remained significant (r = 0.36-0.61), with the exception of P-selectin (not significant, NS), and correlations with SBP were similar (r = 0.35-0.53). A significant correlation was found between PWVs and platelet activation (r = 0.43-0.74). Multiple regression analysis demonstrated significant correlations between platelet activation and reserve and PWVs (coefficient = 2.17-6.59), when both age and BP were adjusted for simultaneously. In conclusion, platelet activation was associated with arterial stiffness, suggesting that arterial stiffness may play an important role in thrombotic events.

Adult↗

PubMed2005

Relationships of C-reactive protein, uric acid, and glomerular filtration rate to arterial stiffness in Japanese subjects.

The relationships between C-reactive protein (CRP), uric acid (UA), glomerular filtration rate (GFR), and arterial stiffness have not been fully investigated. The aim of this study was to clarify whether CRP, UA, and estimated GFR are related to arterial stiffness estimated using brachial-ankle pulse wave velocity (baPWV). The subjects were local government employees (3412 men and 854 women). baPWV, CRP, UA, GFR, and conventional risk factors were evaluated. Multiple linear regression analyses revealed that CRP and UA were significantly related to an elevation of PWV in male and female subjects, and that the estimated GFR was significantly related to an elevation of PWV in male subjects. Significant progressive increases in baPWV were observed across the quartiles of CRP in male subjects and for UA in male and female subjects. In female subjects, the relationship of quartile CRP to baPWV had marginal significance (P = 0.055). But, in male and female subjects, quartile of estimated GFR had no significant association with PWV. These results suggest that CRP and UA are associated with an increase of arterial stiffness in male and female subjects, and that estimated GFR is possibly related to arterial stiffness in male subjects.

Adult↗

PubMed2005

Involvement of transforming growth factor-beta and thrombopoietin in the pathogenesis of myelodysplastic syndrome with myelofibrosis.

We investigated the cause of myelofibrosis and proliferation of megakaryocytes in myelodysplastic syndrome with myelofibrosis (MDS-MF (+)). Plasma-transforming growth factor-beta1 (PTGF-beta1) concentrations closely correlated with myelofibrosis grade in MDS-MF (+) and were higher than those in idiopathic myelofibrosis (IMF), essential thrombocythemia (ET), idiopathic thrombocytopenic purpura (ITP), MDS-without MF (MDS-MF (-)) or healthy volunteers (HV). Peripheral blood mononuclear cells from MDS-MF (+) patients expressed more TGF-beta1 mRNA than those from IMF, MDS-MF (-) or HV. When we immunostained bone marrow specimens of MDS-MF (+) for TGF-beta, the intensity of blasts was apparently higher than that of megakaryocytes, while in MDS-MF (-), megakaryocytes were immunostained with a similar intensity as that in MDS-MF (+), but blasts were negative for staining. In IMF, megakaryocytes, monocytes and small mononuclear cells representing CD34+ cells were all similarly stained with a much lower intensity than that of blasts in MDS-MF (+). The number of bone marrow megakaryocytes were increased the most in MDS-MF (+), followed by ET, ITP, MDS-MF (-) and NHL and correlated with plasma thrombopoietin (TPO) levels or with plasma TGF-beta1 levels, respectively, in each disease. Thus, in MDS-MF (+), both myelofibrosis and the increased megakaryocytes were ascribed to overproduction of TGF-beta1 from blasts.

Adult↗

PubMed2005

Obsessive-compulsive disorder (OCD) with psychotic symptoms and response to treatment with SSRI.

The co-occurrence of obsessive-compulsive and psychotic symptoms in one patient often represents a diagnostic problem. Distinguishing among a schizophrenic disorder with comorbid obsessional symptoms, an OCD with comorbid psychotic symptoms, or an OCD and schizophrenia or any other psychotic disorder is of clinical importance, since the different diagnoses have different therapeutic as well as prognostic implications. In the following case report we describe a patient who suffered from a typical OCD for more than 18 years and then developed clear psychotic symptoms that completely remitted after treatment with citalopram.

Adult↗

PubMed2005

Transport of Clostridium bifermentans DPH-1 through the laboratory column can be explained by two-region model for bioremediation.

Transport of Clostridium bifermentans DPH-1 was characterized from laboratory-made column tests using fully saturated Toyoura sand. The conventional transport models were fitted to the column test results to investigate the applicability of prediction and assessment of bacterial transport in actual subsurface or ground water. Laboratory column tests confirmed that the transport characteristics of Clostridium bifermentans DPH-1 in activating tetrachloroethylene dechlorination could be described by mobile-immobile two-region model. The parameters of two-region model i.e. peclet number, retardation factor, fraction rate of mobile water and stanton number were characterized by fitting results. These parameters were also justified by a verification experiment. Two-region model parameters suggested that bacterial injection into the ground at a large concentration is difficult for rehabilitation of widely dispersed contaminated ground water.

Bacterial Proteins↗

PubMed2005

Quantification and detection of bacteria from postoperative maxillary cyst by polymerase chain reaction.

BACKGROUND/AIMS: Postoperative maxillary cyst (POMC) is known to occur as a delayed complication of radical maxillary sinus surgery, such as Caldwell-Luc surgery. The cyst gradually expands with no symptoms over a period of years, and then occasionally causes swelling and pain in the buccal region and/or the mucogingival fold. It is probable that bacterial infection affects the progression of POMC symptoms. The aims of this study were to determine the bacterial density and to examine the presence of 20 oral bacteria in POMC fluids. METHODS: POMC fluids (4 purulent, 2 mucous and 4 serous) were sampled from 10 subjects (aged 43-77 years). Bacterial quantification and detection were performed by real-time polymerase chain reaction (PCR) and nested PCR based on bacterial 16S rRNA genes, respectively. RESULTS: Bacterial DNA was detected in all samples and the average concentrations of bacterial DNA were 5.9 (purulent), 0.5 (mucous), and 0.7 (serous) ng/mg of sample. Twelve bacterial species, including anginosus streptococci, known to be associated with abscess formation, were detected in the purulent fluids, while two and five species were detected in the mucous and serous fluids, respectively. CONCLUSION: Purulent fluids contained numerous bacteria of various types, thus suggesting that oral bacteria may cause symptoms such as pain in POMC with purulent fluids. Mucous and serous fluids also contained bacteria, although their numbers were small, thus suggesting an association between bacteria and progression of POMC.

Abscess↗

PubMed2005

Testicular dynamics in Syrian hamsters exposed to both short photoperiod and low ambient temperature.

The object of this study was to determine the details of morphological dynamics of spermatogenesis in Syrian hamsters exposed to both short photoperiod and low ambient temperature. Eight-week-old male hamsters, kept in a long photoperiod (14 h L, 10 h D), were transferred to a short photoperiod (6 h L, 18 h D) and kept there for 13 weeks to induce testicular regression. Some hamsters were then transferred from the room at 23 degrees C to that at 5 degrees C (5 degrees C group). Remaining hamsters were continuously kept at 23 degrees C (23 degrees C group). Thereafter, the morphology was examined. As a result, it took only 8 weeks until spermatogenesis recovered in the 23 degrees C group. However, it was not until 20 weeks that spermatogenesis was recognized in the 5 degrees C group. As the regulation of seasonal testicular activity is characterized by coordinated shifts in the relationships among mitosis, meiosis, and apoptosis, the changes in the proliferative and apoptotic activities were examined. Although no significant difference in proliferative activity of spermatogonia between the 5 degrees C and the 23 degrees C groups was confirmed, a notable increase in the rate of apoptosis was observed in the 5 degrees C group. Furthermore, this increase was more salient during the hibernation period. These findings suggest that both cold ambient temperature and hibernation caused the delay of testicular recrudescence and this delay arose from the increase of apoptotic activity but not the change in proliferative activity in spermatogonia in the 5 degrees C group.

Animals↗

PubMed2005

Three-dimensional vasculature of the bovine liver.

To clarify anatomical distribution of Fasciola infection, the vascular and ductal architectures of the liver were studied by means of corrosion cast technique using synthetic resin. The arteria hepatica propria (AP) passes as the arteria gastroduodenalis (AG); AP becomes the left trunk after the porta hepatis; AP passes on the right side of vena porta communis (VPC) and projects AG while curving in a U-shape below the portal vein. Hepatic veins located between the vena hepatica media (HM) and vena hepatica dextra (HD) varied widely among specimens and were irregular, including the vena hepatica dorso-lateralis sinistra (Hds), vena hepatica dorso-lateralis dextra (Hdd), vena hepatica lobi caudati (Hlc), venae hepaticae processus caudati (Hpc), venae hepaticae processus papillaris (Hpp), and the hepatic vein to the dorsal intermediate part, which directly or indirectly drained into the vena cava caudalis. The courses of the bovine hepatic veins were markedly diverse, and anastomoses between vena hepatica sinistra (HS) and Hds were observed in about a half of the livers. The portal vein entered the liver as VPC slightly above the centre of the right lobe on the visceral surface. The intermediate or transverse part [pars transversa trunci sinistri (PTS)] of truncus sinister (TS), which extends from the entry of the portal vein into the left lobe of the liver, was slightly arched downward [pars umbilicalis trunci sinistri (PUS)]. The portal vein further arched from the distal end of TS to the umbilical vein and ran towards the inter-lobar incision between the left lobe and quadrate lobe. Based on these branches, hepatic segments were determined as 13 or 14 areas. A total of 15 bile ducts were derived from various lobes. The hepatic duct was about 2.6-6 cm long from the confluence of the right and left hepatic ducts to the division of the cystic duct and the common hepatic duct.

Animals↗

PubMed2005

Peritoneal biphasic mesothelioma in a dog.

A 10-year-old German shepherd dog was presented with a severe abdominal distension. At necropsy, whitish and firm mass was observed in the mesentery with metastases in the pericardium and pleura. The intestinal serosa was thickened and stiff. Histologically, the tumours were composed of a biphasic population of cells, which reacted with cytokeratin, vimentin and Wilms' tumour 1 protein antibody. Ultrastructural examination revealed numerous microvilli, abundant rough endoplasmic reticulum, numerous desmosomes and bundles of microfilament. The tumour was classified as biphasic mesothelioma of peritoneal origin.

Animals↗