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T Shimizu

Publications and source records attributed to T Shimizu.

At least 91 records · Page 5Linked to original sources
PubMed2004

Histopathological evaluation of 0-h biopsy specimens of donor kidney procured by laparoscopic donor nephrectomy.

UNLABELLED: We evaluated the histopathology of donor kidneys procured by laparoscopic donor nephrectomy (LDN), by examining allograft biopsy specimens obtained immediately after donor nephrectomy (0-h biopsies). MATERIALS AND METHODS: LDN was performed on 65 donors between December 1999 and November 2002, in our institution. Their mean age was 56 years, and there were 19 males and 46 females. Hand-assisted LDN (HALDN) was used in 10 cases and retroperitoneal LDN (RPLDN) in 55 cases. Allograft biopsy of all 65 kidneys was performed immediately after LDN (0-h biopsy), and the biopsy specimens were used in this study. All specimens were routinely examined by light and immunofluorescence microscopy. The 43 donors who underwent traditional open donor nephrectomy (ODN) between January 2001 and June 2001 served as controls. RESULTS: There was no significant difference in the rate of glomerular sclerosis and moderate interstitial fibrosis with tubular atrophy, the severity of arteriosclerosis, and the severity of arteriolar hyalinosis among the specimens from kidneys removed by the three different methods: HALDN, RPLDN, and ODN. Prominent and characteristic histopathological changes which are not usually seen in 0-h biopsy specimens of kidneys obtained by traditional ODN were 'subcapsular cortical damage (SCCD) with capsular lesions (CL)'. The SCCD with CL changes included a subcapsular degeneration and necrosis of tubular cells and a congestion of glomerular and peritubular capillaries (SCCD) associated with haemorrhage and fibrin deposits in the renal capsule (CL). In this study, such characteristic 'SCCD with CL' findings were observed in 35 specimens (54%). The damage was much milder in donor kidneys procured by RPLDN than by HALDN. CONCLUSION: SCCD with CL occurred in donor kidneys procured by LDN, which may be due to a compression of the renal parenchyma and veins. RPLDN may be better method for donor nephrectomy.

Adult↗
PubMed2004

Suppressive effects of breast milk on oxidative DNA damage in very low birthweight infants.

BACKGROUND: Human milk contains many kinds of antioxidant and is considered to prevent diseases mediated by oxygen free radicals in very low birthweight (VLBW) infants. AIMS: To examine the antioxidant effects of breast milk in VLBW infants by determining urinary 8-hydroxydeoxyguanosine (8-OHdG) excretion, which is known to be a non-invasive marker for in vivo oxidative DNA damage. METHODS: Urinary 8-OHdG concentrations were measured in 15 breast fed and 14 formula fed VLBW infants at 2, 7, 14, and 28 days of age. RESULTS: Urinary 8-OHdG excretion at 14 and 28 days of age was significantly lower than at 2 and 7 days of age in the breast fed group, and significantly lower than in the formula fed group. CONCLUSION: This is the first direct evidence of the antioxidant action of human milk in VLBW infants.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2004

Genetic analysis of crown size in the first molars using SMXA recombinant inbred mouse strains.

Tooth crown size may be determined by both genetic and environmental factors. The aim of this study was to identify quantitative trait loci (QTLs) affecting dental crown size and determine whether there is genetic independence between upper and lower teeth, using SMXA recombinant inbred strains of mice. Mesiodistal and buccolingual crown diameters (MD and BL, respectively) of the upper and lower first molars (M(1) and M(1), respectively) were measured. For each trait, mean values of substrains showed a continuous spectrum of distribution. Genome-wide scan detected QTLs exceeding suggestive threshold levels for MD of M(1) (chromosomes 7, 13, and 17), BL of M(1) (chromosomes 8 and 13), MD of M(1) (chromosomes 7 and 13), and BL of M(1) (chromosomes 3 and 15). These findings suggest that tooth crown size is controlled by multiple genes, and that there is some independence of genetic control between M(1) and M(1).

Animals↗
PubMed2004

Molecular epidemiology of tuberculosis in the north Hokkaido district of Japan.

SETTING: The incidence of tuberculosis in Japan has fallen rapidly in the past 50 years, to 27.9 cases per 100,000 population in 2001. OBJECTIVE: To assess the molecular epidemiology of tuberculosis in the north Hokkaido district, Japan. DESIGN: Restriction fragment length polymorphism analysis was consecutively performed on Mycobacterium tuberculosis strains from patients with pulmonary tuberculosis from April 1999 to March 2002. RESULTS: Of 229 patients, strains from 227 (99.1%) were available for analysis. The mean age of the patients analysed was 69.4 years. There was one immigrant patient. Two hundred and seven patients had six or more copies of IS6110. Of these, 16 (7.7%) in eight clusters had identical patterns, 120 (58.0%) belonged to five groups that had similar patterns (Dice coefficient >0.7) and 80 (38.6%) belonged to the 35 groups with the most common patterns (Dice coefficient >0.9). CONCLUSION: These results may reflect the epidemiological characteristics, age and migration of the residents and the incidence of tuberculosis of the area, and also those of Japan: many elderly patients were infected in the past, when the incidence of tuberculosis was very high.

Adolescent↗
PubMed2004

[Thymothymectomy for the thymoma with pure red cell aplasia; report of a case].

UNLABELLED: We report a case of thymothymectomy for the thymoma with pure red cell aplasia (PRCA). A 31-year-old male with a general fatigue had a severe anemia (hemoglobin 3.1 g/dl) since November 1997. By the bone marrow examination, PRCA was diagnosed and treated with blood transfusion and immunosuppressive drug (cyclosporin: CYA) administration but anemia had not been improved. The chest computed tomography displayed a 3 cm in a diameter of thymoma located in the anterior mediastinum. The extended thymothymectomy had been performed in February 1998, pathological detection disclosed Masaoka classification stage I, type AB was diagnosed due to the World Health Organization (WHO) classification. PRCA had not obtained an immediate remission during the postoperative-early term, while, adjuvant therapy (CYA 300 mg/day) has been continued and it brought a complete remission of PRCA in August 2001 (after the postoperative 3 years and 6 months later). CONCLUSIONS: Even though only thymothymectomy for thymoma with PRCA showed no effectiveness for the postoperative-early remission of PRCA, however, the combination of thymectomy and the postoperative adjuvant therapy (CYA) should bring a better outcome, and the continuous follow-up would be required for a long postoperative term.

Adult↗
PubMed2004

[Bilateral lower lobectomies for pulmonary mucormycosis].

Mucormycosis is an extremely rare case of pulmonary mycosis, its prognosis is very poor, and known as an opportunistic infection among immunocompromised hosts accompanied with other primary chronic disease. We report here a case of bilateral lower lobectomies carried out by two-stage operation for pulmonary mucormycosis combined with diabetes mellitus (type I) and severe resistance to an antimycobiotics under biblicographical considerations. A 36-year-old female was diagnosed as a diabetes mellitus (type I), and has been administrated with an insulin injection in 1989 at the age of 22-year-old. The patient was suffered a dry cough in June and the bilateral abnormal shadows were pointed out by the chest X-ray film in November, 2002. By transbronchial lung biopsy, Mucor fungus was confirmed in grannulomatous lung specimen. Intravenous injection of amphotericin B could not be continued due to the unavoidable side-effects from this agent. As the lung mass shadow was enlarged increasing and strongly suggested an abscess, formation in its focus, and then the left lower lobectomy was performed as the first step of surgical treatment and the right lower lobectomy was done on the postoperative forty-fourth day as the second step. The postoperative prognosis was considerably uneventful. After bilateral lower lobectomies, the patient could try a walk and go upstairs with a moderate dyspnea. A possible surgical resection should be conducted for the pulmonary mucormycosis, when the medicinal therapy showed an uneffectiveness and/or an infectious lesion was shown as restricted lesion.

Adult↗
PubMed2003

Comparison of PCR-amplified JC virus control region sequences from multiple brain regions in PML.

The authors report a 14-year-old boy with Wiskott-Aldrich syndrome complicated by progressive multifocal leukoencephalopathy after allogeneic bone marrow transplantation. Several therapeutic approaches were attempted, but there was no response. The patient died 2 months after the onset of neurologic symptoms. We detected three distinct, rearranged regions of JC virus in the cerebellum, occipital lobe, and brainstem. These findings suggest that the brain lesions had three independent origins.

Adolescent↗
PubMed2003

CSF hypocretin levels in Guillain-Barré syndrome and other inflammatory neuropathies.

CSF hypocretin-1 was measured in 28 Guillain-Barré syndrome (GBS), 12 Miller-Fisher syndrome, 12 chronic inflammatory demyelinating polyneuropathy (CIDP), and 48 control subjects. Seven GBS subjects had undetectably low hypocretin-1 levels (<100 pg/mL). Hypocretin-1 levels were moderately reduced in an additional 11 GBS, 5 Miller-Fisher syndrome, and 1 CIDP subject. Low levels in GBS occurred early in the disease and were associated with upper CNS level abnormalities.

Adolescent↗
PubMed2003

Mechanism of superconductivity in the polyhedral-network compound Ba8Si46.

The silicon clathrates--materials composed of metal-doped Si(20) dodecahedra--were identified as the first superconductors based on pure silicon networks. The mechanism of superconductivity in these materials can be obtained by studying their phonon modes, as modified by isotope substitution, and specific-heat measurements. Here, we present experimental studies that provide strong evidence that superconductivity in Ba(8)Si(46) is explained in the framework of phonon-mediated Bardeen-Cooper-Schriefer theory. Analyses using the McMillan approximation of the Eliashberg equation indicate that the superconducting mechanism is in the medium coupling regime, but at the high-end limit. The large density of states at the Fermi level, which arises from hybridization of the Si(20) cluster and Ba orbitals, is responsible for the unexpectedly high superconducting temperature. The temperature evolution of the specific heat unambiguously shows that this is an s-wave symmetry superconductor.

Journal Article↗
PubMed2003

Comparative antimicrobial activities of gatifloxacin, sitafloxacin and levofloxacin against Mycobacterium tuberculosis replicating within Mono Mac 6 human macrophage and A-549 type II alveolar cell lines.

Mycobacterium tuberculosis (MTB) is capable of invading not only macrophages (Mphis) but also type II pneumocytes. In this study, we compared the antimicrobial activities of fluoroquinolones, including gatifloxacin, sitafloxacin and levofloxacin, against the MTB replication in the Mono Mac 6 human Mphi cell line (MM6-Mphis) and the A-549 human type II alveolar epithelial cell line (A-549 cells). When test quinolones were added at the MIC (0.125, 0.06 and 0.25 mg/l for gatifloxacin, sitafloxacin and levofloxacin, respectively) to the culture media of MTB-infected cells, these drugs exerted growth-inhibitory activity against intracellular organisms in the order of sitafloxacin > gatifloxacin > levofloxacin. On the other hand, when test quinolones were added at Cmax in the blood (1.7, 1.0 and 2.0 mg/l for gatifloxacin, sitafloxacin and levofloxacin, respectively), these drugs exhibited bactericidal activity against intracellular MTB in the order of gatifloxacin > sitafloxacin > or = levofloxacin. In addition, when test drugs were added at 1/8 C(max) to 1/2 C(max), the efficacy was in the order of sitafloxacin > gatifloxacin > levofloxacin. Thus, it appears that the MIC values of fluoroquinolones are not always predictive of their antimicrobial activity against intracellular MTB. In this context, it was also found that intracellular uptake of these quinolones by MM6-Mphis and A-549 cells was in the order of sitafloxacin > gatifloxacin > levofloxacin. This implies that the cellular permeability of these quinolones is an important factor that determines their efficacy to eliminate intracellular MTB organisms.

Anti-Infective Agents↗
PubMed2003

Virus-induced silencing of WIPK and SIPK genes reduces resistance to a bacterial pathogen, but has no effect on the INF1-induced hypersensitive response (HR) in Nicotiana benthamiana.

Activation of two mitogen-activated protein kinases (MAPKs), wound-induced protein kinase (WIPK) and salicylic acid-induced protein kinase (SIPK), is one of the earliest responses that occur in tobacco plants that have been wounded, treated with pathogen-derived elicitors or challenged with avirulent pathogens. We isolated cDNAs for these MAPKs (NbWIPKand NbSIPK) from Nicotiana benthamiana. The function of NbWIPK and NbSIPK in mediating the hypersensitive response (HR) triggered by infiltration with INF1 protein (the major elicitin secreted by Phytophthora infestans), and the defense response to an incompatible bacterial pathogen (Pseudomonas cichorii), was investigated by employing virus-induced gene silencing (VIGS) to inhibit expression of the WIPK and SIPK genes in N. benthamiana. Silencing of WIPK or SIPK, or both genes simultaneously, resulted in reduced resistance to P. cichorii, but no change was observed in the timing or extent of HR development after treatment with INF1.

Algal Proteins↗
PubMed2003

Mice deficient in cytosolic phospholipase A2 are less susceptible to cerebral ischemia/reperfusion injury.

To determine the role of cytosolic phospholipase A2 (cPLA2) in infarct development, wild-type and cPLA2 knock-out mice were subjected to focal cerebral ischemia for 75 min by occluding the middle cerebral artery using nylon filament and subsequent reperfusion by withdrawing the filament. The neurological deficit severity was evaluated by a modified 4-point scale. After the reperfusion period (72 h), mice were killed, and the brains were cut into four 2 mm coronal sections using a rodent brain matrix. Sections were stained with 2% 2,3,5-triphenyltetrazolium chloride (TTC). The infarct volume was 87.19 +/- 27.54 mm3 (mean +/- SD, n = 11) in the wild-type mice and 48.20 +/- 31.32 mm3 (n = 10; P < 0.01 vs. wild-type) in the knock-out mice. Less severe functional neurological deficits were observed in knock-out mice at 72 h after ischemia when compared with wild-type. Thus, disruption of cPLA2 resulted in significant reduction of infarct area and neurological deficit severity in the MCA occlusion model. These data indicate a critical role for cPLA2 in the pathogenesis of cerebral ischemia/ reperfusion injury.

Animals↗
PubMed2003

Hand-assisted laparoscopic hepatectomy after partial splenic embolization.

The case of a patient with hepatocellular carcinoma and thrombocytopenia secondary to liver cirrhosis who underwent successful hand-assisted laparoscopic hepatectomy after partial splenic embolization is described. A 67-year-old man with severe liver cirrhosis was admitted for treatment of hepatocellular carcinoma. His early phase of hepatic angiography showed two hypervascular tumors in segment 6. The patients liver function was poor, with the indocyanine green retention at 15 min of 49.5%, a total serum bilirubin concentration of 2.0 mg/dl, an albumin concentration of 2.8 g/dl, and an hyaluronic acid concentration of 649 ng/ml. The platelet count was 3.0 x 10(4)/microl secondary to hypersplenism. Partial splenic embolization decreased the splenic volume by 50% preoperatively. At 2 months later, the platelet count was 6.0 x 10(4)/microl, and hand-assisted laparoscopic partial hepatectomy was performed uneventfully. The patients postoperative course was unremarkable, and he was discharged on postoperative day 12.

Aged↗
PubMed2003

Prognostic significance of bcl-2 expression in resected pN2 non-small cell lung cancer.

AIMS: The prognosis of non-small cell lung cancer with pathologic mediastinal lymph node involvement (pN2) is poor, we wished to study the expression of p53, bcl-2 by immunohistochemistry in a series of such patients. METHODS: Clinicopathologic factors were investigated in relation to prognosis in 60 patients with resected pN2 non-small cell lung cancer. RESULTS: The 5-year survival rate was 21.7%. Positive staining for p53, and bcl-2 was found in 29/60 and 12/60, respectively. Patients with bcl-2 positive tumor had a more favorable survival than those with bcl-2 negative tumor (P=0.0054). The expression of p53 was not related to patients' survival. Multivariate analysis showed that Bcl-2 expression and single N2 station were independent prognostic factors. CONCLUSIONS: Patients with bcl-2 positive tumors may comprise a favorable prognostic subgroup in pN2 non-small cell lung cancer.

Adult↗
PubMed2003

Effects of n-3 polyunsaturated fatty acids on indomethacin-induced changes in eicosanoid production and blood flow in the gastric mucosa of rats.

We investigated the effects of n-3 polyunsaturated fatty acids (PUFAs) on non-steroidal anti-inflammatory drug (NSAID)-induced changes in microcirculation and eicosanoid production in the gastrointestinal mucosa. We measured gastric mucosal blood flow using laser Doppler flowmetry, assessed the fatty acid composition in the mucosal phospholipids, and quantified the production of prostaglandin E2 (PGE2), leukotriene B4, and leukotriene C4 (LTB4 and C4) from the mucosa with the stimulation of calcium ionophore 20 min after an injection of indomethacin or vehicle in rats fed a diet containing different compositions of alpha-linolenic acid. Four weeks after the initiation of the test diet the arachidonic acid level in gastric mucosal phospholipids was significantly lower in the perilla group than in the other three groups. Conversely, alpha-linolenic acid and eicosapentaenoic acid (EPA) were significantly higher in the perilla group than in the other three groups. The percent of gastric mucosal blood flow in the three groups administered indomethacin were significantly lower than that in the control group injected with vehicle alone. The percent of gastric mucosal blood flow in the perilla group was significantly higher than that in the corn group. LTB4 and LTC4 production from the gastric mucosa in the soybean and corn groups were significantly higher than those in the control group, and the LTC4 production in the perilla group was significantly lower than that in the corn group. There were no significant differences in PGE2 production among the four groups. Our results suggest that alpha-linolenic acid affectively suppressed the indomethacin-induced decreases in gastric mucosal blood flow by increasing EPA and decreasing the levels of arachidonic acid and LTC4 in the gastric mucosa.

Animals↗
PubMed2003

Environmental isolates of Citrobacter braakii that agglutinate with Escherichia coli O157 antiserum but do not possess the genes responsible for the biosynthesis of O157 somatic antigen.

While searching for Escherichia coli O157 in the aquatic environment of Calcutta using an immunodetection procedure, we fortuitously detected five strains of Citrobacter braakii, which cross-reacted with the commercially available O157 polyvalent antiserum. The five C. braakii isolates gave positive results when a sensitive dot-ELISA was performed with E. coli O157 monoclonal antibody. Further, the O157 monoclonal antibody recognized the bands of proteinase K treated whole cells of lipopolysaccharide of all the C. braakii isolates. Apart from weak reactions with two or three of the DNA probes, all the C. braakii strains did not hybridize with the other probes spanning the minimum region required for O157 O-antigen biosynthesis. These strains did not possess any of the virulence genes that are commonly found in the Shiga toxin-producing E. coli (STEC) specially the serotype O157: H7. Therefore, it appears that the serological cross-reaction between C. braakii and E. coli O157 antiserum is based on structural mimicry between the O-polysaccharide of C. braakii and E. coli O157.

Agglutination↗