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T Sameshima

Publications and source records attributed to T Sameshima.

At least 19 recordsLinked to original sources
PubMed2001

Preoperative assessment of vascularity by color Doppler ultrasonography in human rectal carcinoma.

PURPOSE: Although angiogenesis assessed by immunostaining endothelial cells (microvessel density) is a well-known prognostic factor in a wide variety of human solid tumors, preoperative determination of microvessel density seems to be difficult in rectal carcinoma. Thus, we performed transanal color Doppler ultrasonography in 46 patients with rectal carcinoma to assess preoperative angiogenic status and compare it with microvessel density in surgical specimens. METHODS: Time-averaged maximal velocity, peak systolic velocity, number of vascular points, and vascular point index were conducted by color Doppler ultrasonography in 46 patients with rectal carcinoma. Number of vascular points was defined as the number of vessels with pulsation in the section of tumor. Vascular point index was defined as the average number of vascular points divided by the area assessed by color Doppler ultrasonography in the section of tumor. The profiles of number of vascular points were similar to those assessed by microangiography in five rectal carcinomas. RESULTS: Vascular point index significantly correlated with microvessel density (P < 0.0001). No significant correlation was found between microvessel density and time-averaged maximal velocity or peak systolic velocity. Vascular point index was also a better indicator of lymph node metastasis and venous invasion than microvessel density. In addition, 11 of 46 cases with postoperative hematogenous metastasis (23.9 percent) were observed prospectively. Vascular point index may be a best predictor for hematogenous metastasis from rectal carcinoma compared with peak systolic velocity, time-averaged maximal velocity, and microvessel density by receiver operating characteristic analysis. CONCLUSION: These results suggest that preoperative quantification of angiogenesis using color Doppler ultrasonography will provide quick and useful information in the management of rectal carcinoma.

Blood Flow Velocity↗
PubMed2001

Molecular typing and epidemiological study of Salmonella enterica serotype Typhimurium isolates from cattle by fluorescent amplified-fragment length polymorphism fingerprinting and pulsed-field gel electrophoresis.

One hundred twenty Salmonella enterica serotype Typhimurium strains, including 103 isolates from cattle gathered between 1977 and 1999 in the prefecture located on the northern-most island of Japan, were analyzed by using fluorescent amplified-fragment length polymorphism (FAFLP) and pulsed-field gel electrophoresis (PFGE) to examine the genotypic basis of the epidemic. Among these strains, there were 17 FAFLP profiles that formed four distinct clusters (A, B, C, and D). Isolates that belonged to cluster A have become increasingly common since 1992 with the increase of bovine salmonellosis caused by serotype Typhimurium. PFGE resolved 25 banding patterns that formed three distinct clusters (I, II, and III). All the isolates that belonged to FAFLP cluster A, in which all the strains of definitive phage type 104 examined were included, were grouped into PFGE cluster I. Taken together, these results indicate that clonal exchange of serotype Typhimurium has taken place since 1992, and they show a remarkable degree of homogeneity at a molecular level among contemporary isolates from cattle in this region. Moreover, we have sequenced two kinds of FAFLP markers, 142-bp and 132-bp fragments, which were identified as a polymorphic marker of strains that belonged to clusters A and C, respectively. The sequence of the 142-bp fragment shows homology with a segment of P22 phage, and that of the 132-bp fragment shows homology with a segment of traG, which is an F plasmid conjugation gene. FAFLP is apparently as well suited for epidemiological typing of serotype Typhimurium as is PFGE, and FAFLP can provide a source of molecular markers useful for studies of genetic variation in natural populations of serotype Typhimurium.

Animals↗
PubMed2000

Expression of emmprin (CD147), a cell surface inducer of matrix metalloproteinases, in normal human brain and gliomas.

EMMPRIN (extracellular matrix metalloproteinase inducer), also called CD147, basigin or M6 in the human, is a member of the immunoglobulin superfamily that is present on the surface of tumor cells and stimulates adjacent fibroblasts to produce matrix metalloproteinases (MMPs). In our study, we investigated expression of EMMPRIN in human normal brain and gliomas, since mouse basigin and chicken HT7, the species homologues of human EMMPRIN, are associated with neuronal interactions and normal blood-brain barrier function, respectively. EMMPRIN expression was detected in all samples of non-neoplastic brain and glioma tissues examined. However, expression levels of EMMPRIN mRNA and protein were significantly higher in gliomas than in non-neoplastic brain. Moreover, levels of mRNA expression and immunohistochemical staining correlated with tumor progression in gliomas: They were highest in the most malignant form of glioma, glioblastoma multiforme, followed by anaplastic astrocytoma and then low-grade astrocytoma. Also, immunolocalization revealed quite different distributions in non-neoplastic brain and glioma: EMMPRIN was demonstrated only in vascular endothelium in non-neoplastic regions of the brain, whereas it was present in tumor cells but not in proliferating blood vessels in malignant gliomas. These data indicate that an MMP inducer molecule EMMPRIN is differently expressed in human normal brain and gliomas and could be associated with astrocytoma progression. Possible mechanisms whereby glioma cell EMMPRIN could influence tumor progression will be discussed.

Antigens, CD↗
PubMed2000

Glioma cell extracellular matrix metalloproteinase inducer (EMMPRIN) (CD147) stimulates production of membrane-type matrix metalloproteinases and activated gelatinase A in co-cultures with brain-derived fibroblasts.

Extracellular matrix metalloproteinase inducer (EMMPRIN) also called CD147, basigin or M6 in the human is a member of the immunoglobulin superfamily that is enriched on the surface of tumor cells and stimulates adjacent stromal cells to produce several matrix metalloproteinases (MMPs). In this study, we have demonstrated that coculturing of EMMPRIN-expressing human glioblastoma multiforme cells (U251) with brain-derived human fibroblasts not only stimulates production, but also activation of pro-gelatinase A (proMMP-2), an enzyme that is enriched in malignant gliomas and most likely crucial to tumor progression. Production of membrane types 1 and 2-MMPs (MT1-MMP and MT2-MMP), which are activators of proMMP-2, was also stimulated in these cocultures. Stimulation of MMP-2, MT1-MMP and MT2-MMP production was inhibited by anti-EMMPRIN monoclonal antibody in a dose-dependent manner. Thus, we have shown, for the first time, that EMMPRIN causes increased expression of MT1-MMP and MT2-MMP, as well as increased production and activation of MMP-2.

Antibodies, Monoclonal↗
PubMed2000

Clonal turnover of enterohemorrhagic Escherichia coli O157:H7 in experimentally infected cattle.

A total of 401 enterohemorrhagic Escherichia coli (EHEC) O157:H7 isolates from two experimentally infected calves were analyzed using molecular biological methods. Genetic differences detected by pulsed-field gel electrophoresis were observed between the inoculated and recovered strains as early as 1 day post inoculation. The loss of the inoculated clone was observed in one calf. Replication and dissemination of the EHEC O157:H7 strains that mutated in cattle may result in the diversification of this organism among cattle populations.

Animals↗
PubMed2000

Multiple duodeno-jejunal diverticula causing massive intestinal bleeding.

A case of massive intestinal blood loss from multiple duodeno-jejunal diverticula is described. A 39-year-old man was referred to our hospital because of recurrent bloody stool and worsening anemia. Upper and lower endoscopy, selective abdominal angiography, and radionuclide scanning were performed to seek the cause of the intestinal bleeding, but none of these studies revealed the source of bleeding. Small-bowel barium follow-through examination showed numerous diverticula in the distal duodenum and proximal jejunum. Excision of the duodenal diverticulum and resection of the involved portion of the jejunum cured the patient. On histopathological examination, an ulcerative lesion with an exposed vessel suggestive of the source of bleeding was seen in the resected duodenal diverticulum. Although duodeno-jejunal diverticula are rare, the importance of a careful search for this malformation in a patient with intestinal blood loss is stressed.

Adult↗
PubMed2000

A comparison of Escherichia coli O157 isolates from cattle in Japan and the USA by molecular biological methods.

Escherichia coli O157 isolates from cattle in Japan (n = 91) and in the USA (n = 415) were compared by pulsed-field gel electrophoresis of endonuclease-cleaved genomic DNA, location of the stx genes and bacteriophage typing. Three isolates from cattle in Japan with high similarity to isolates from cattle in the USA were found. Isolates from cattle farms in Japan and the USA may share a common source.

Animals↗
PubMed2000

Angiographic cerebral circulation time before and after endovascular therapy for symptomatic vasospasm.

AIM: To investigate the correlation between angiographic cerebral circulation time (CCT) and cerebral blood flow (CBF) evaluated by single photon emission computed tomography (SPECT) before and after endovascular treatment for symptomatic vasospasm. MATERIALS AND METHODS: Seven patients with unilateral vasospasm as demonstrated by catheter angiography who underwent pre- and post-treatment SPECT were selected. All patients had angiographic vasospasm of unilateral middle cerebral artery (MCA). Eight vessels in seven patients underwent intra-arterial papaverine infusion and three vessels underwent percutaneous transluminal angioplasty. Angiographic CCT was defined as the interval from the first image in which contrast medium was visible at the origin of MCA to its disappearance from the cortical arteries in the MCA territory. In SPECT studies, the ischaemic degree in MCA territory was analysed by side to side comparison with calculating the asymmetry index (AI). RESULTS: The pre-treatment mean CCT was 4.1 +/- 0.8 s. The mean CCT immediately after treatment was 2.7 +/- 0.5 s. In the control subjects (n = 15) with unruptured aneurysm, mean CCT was 3.5 +/- 0.2 s. The pre-treatment mean CCT was significantly prolonged compared with that in the control subjects (P = 0.02). The post-treatment mean CCT was significantly shortened compared with that in the control subjects (P = 0.001). The pre-treatment mean AI was 71.2 +/- 7.4%, and that immediately after treatment was 90.5 +/- 3.6%. AI increased in all territories treated with endovascular treatment; the mean change was 19.3%. Angiographic CCT was closely correlated with AI in both pre- (r = - 0.95) and post-treatment (r = - 0.79). CONCLUSION: Measurement of CCT is useful in evaluating cerebral haemodynamics of endovascular treatments in patients with cerebral vasospasm.

Adult↗
PubMed2000

Cord blood banking: volume reduction using "Procord" Terumo filter.

Cryopreserved cord blood (CB) banking, space storage, and ABO major incompatibility transfusion as well as potential progenitor cell loss during processing, are the subjects of this study. We evaluate processing of fresh and thawed CB on "Procord" (Terumo Corp., Japan). On 16 freshed CBs, mean NC, CD34, CFU-GM yields were, respectively, 54% (SD +/- 20), 75% (SD +/- 25), and 171% (SD +/- 168) in a final volume of 20 ml. Final product was enriched in mononuclear cells (mean 69% granulocytes depletion) with reproducible erythrocyte and platelet depletions means of 97% (SD +/- 1.5) and 93% (SD +/- 8). On seven previous whole frozen CB units, Procord gave comparable red blood cell (98%) depletion with 53% (SD +/- 30) mean CD34 recovery. Procord is an efficient method for erythrocyte depletion of CB, and recoveries of NC and progenitor cells are comparable to those obtained with similar processing. Nevertheless, as all existing methods, it is associated with cell and progenitor cell loss.

Antigens, CD34↗
PubMed2000

Unilateral middle cerebral artery stenosis in an adult with Down's syndrome--case report.

A 29-year-old male with Down's syndrome presented with severe headache and vomiting. Computed tomography demonstrated subarachnoid hemorrhage. Left carotid angiography showed severe stenosis of the middle cerebral artery 2 cm distal to its origin, as well as abnormal hyper-vascularization near the stenosis site similar to that seen in moyamoya disease. Right carotid angiography showed no abnormalities. However, slight stenosis of the distal part of the bilateral vertebral arteries was noted. There was no aneurysm. We judged that the subarachnoid hemorrhage had been caused by rupture of the moyamoya-like vessel. Some patients with Down's syndrome have anatomical vascular abnormality and vascular fragility. The cerebral vascular abnormality found in this case may be part of the systemic vascular abnormalities associated with Down's syndrome. The vascular changes in some adult patients with Down's syndrome may be a sign of premature aging, and long-term studies with periodic vascular examination of patients with Down's syndrome need to be performed.

Adult↗
PubMed2000

Salmonella typhimurium DT104 from livestock in Japan.

We examined the distribution of multidrug-resistant Salmonella enterica serotype Typhimurium definitive phage type 104 (DT104) among Japanese livestock from 1973 to 1998. The 144 S. Typhimurium field isolates were tested for susceptibility to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline, kanamycin, trimethoprim, nalidixic acid, and norfloxacin. Thirty-six of 68 strains which exhibited resistance to five or more antimicrobials (ACSSuT+) were identified as DT104. Results of plasmid profiling showed that all DT104 strains retain a 90-kb virulence plasmid, while 20 of 36 strains possessed a few additional small plasmids ranging from 2 to 4 kb. These results showed that DT104 strains have existed in Japanese livestock since 1990, and that this phage type may be an important pathogen for cattle in Japan.

Animals↗
PubMed2000

Radiographic and scintigraphic courses of union in cervical interbody fusion: hydroxyapatite grafts versus iliac bone autografts.

UNLABELLED: This study investigated the radiographic and scintigraphic courses of union in cervical interbody fusion using hydroxyapatite (HA) grafts or iliac bone autografts. METHODS: Twelve patients underwent both serial plain radiography and bone scintigraphy during the 12 mo after surgery. Serial plain radiographs were obtained every month until the end of the study period. Bone scintigrams with 99mTc-hydroxymethylene diphosphonate (HMDP) were obtained at 2 wk and at 1, 2, 3, and 6 mo. Uptake of 99mTc-HMDP in the graft was expressed as a ratio of the counts in the graft to those in the axis. RESULTS: In the HA graft group, the plain radiographs of all patients showed a radiolucent stripe that disappeared 7.3 +/- 1.5 (mean +/- SD) months after surgery. In the autograft group, a radiolucent stripe around the graft was not seen for any patient, and union was confirmed by follow-up radiographs within 6 mo after surgery. The serial changes in the 99mTc-HMDP uptake ratio showed no difference between the 2 groups. The 99mTc-HMDP uptake ratio peaked 1 mo after surgery and decreased rapidly to a plateau within 2 mo. CONCLUSION: In the HA graft group, despite the presence of a radiolucent stripe around the graft for more than 6 mo, the scintigraphic course of union was not different from that in the autograft group. The likelihood is that the presence of a radiolucent stripe around the HA graft in the early months after surgery is not always a sign of pseudoarthrosis.

Biocompatible Materials↗
PubMed1999

Salmonella Abortusequi strains of equine origin harbor a 95kb plasmid responsible for virulence in mice.

Most Salmonella choleraesuis subsp. choleraesuis serovar Abortusequi strains of equine origin harbor a 95kb plasmid, pSA95. Results of PCR and Southern blot analysis suggest that pSA95 contains spv genes. A pSA95-cured strain of S. Abortusequi was 48 times less virulent to mice than its parental strain. Virulence was restored by reintroduction of pSA95. These results provide clear evidence that pSA95 confers virulence on S. Abortusequi in mice. This is the first report describing a virulence plasmid of S. Abortusequi.

Animals↗
PubMed1999

Clinical usefulness of and problems with three-dimensional CT angiography for the evaluation of arteriosclerotic stenosis of the carotid artery: comparison with conventional angiography, MRA, and ultrasound sonography.

BACKGROUND: Prevention of stroke is aided by determination of the degree of carotid artery stenosis and progression of arterial sclerosis. Three-dimensional computed tomography (CT) angiography (3D-CTA) is a new method for evaluating the degree of arterial stenosis. The purpose of this study was to compare the accuracy of 3D-CTA with the "gold standard": conventional angiography, magnetic resonance angiography (MRA), and ultrasound sonography (US). METHODS: A total of 128 carotid bifurcations in 64 patients (42 men and 22 women; mean age, 68.5 years) were examined by 3D-CTA because of symptoms of cerebral infarction, carotid bruit, or findings suggestive of arteriosclerotic carotid artery stenosis on MRA screening. The following were used to compare 3D-CTA with conventional angiography, MRA and US: 1) estimation of the degree of stenosis; 2) depiction of irregularities in arterial walls, including calcification, intimal thickening, ulcers and plaque; and 3) surgical planning for carotid endarterectomy (CEA) and percutaneous transluminal angioplasty (PTA), and postoperative evaluation. RESULTS: A strong correlation was found between the degrees of stenosis estimated by conventional angiography and 3D-CTA MIP image (r = 0.987/p < 0.0001). On the other hand, stenosis was generally overestimated by MRA, which, however, has the advantage of being able to scan the carotid siphon to the middle cerebral artery at one time. Calcification and ulceration of the artery wall could be evaluated with 3D-CTA, whereas with US, progression of arterial sclerosis could be evaluated by differentiation of homogenous and heterogenous plaque. The anatomical relationships between the site of stenosis and the internal jugular vein and bony structures, which must be known before CEA, were confirmed by observation of rotated images using the shaded surface reconstruction (SSR) method. Because the hemodynamics of cross and collateral flows cannot be clearly imaged with 3D-CTA, standard angiography is needed to determine suitability for bypass surgery. CONCLUSIONS: The current method used in our hospital for the diagnosis of stenosis of the internal carotid artery includes MRA or US for initial screening, 3D-CTA for evaluation of the degree of stenosis and for preoperative and postoperative evaluation of CEA and PTA, and conventional angiography for evaluation of hemodynamics and determination of the indications for a bypass surgery.

Aged↗
PubMed1999

Molecular typing of Escherichia coli O157:H7 (H-) isolates from cattle in Japan.

A total of 77 Escherichia coli O157:H7 (H-) isolates from cattle in Japan were investigated by molecular biological methods. Most of these isolates (43 isolates) possessed the stx-2 gene, but not stx1. Fifteen bacteriophage types and 50 pulsed-field gel electrophoresis (PFGE) profiles were observed. One isolate was indistinguishable from the human outbreak strain by these methods. This indicates that cattle must be considered as a possible source of human E. coli O157:H7 infection in Japan.

Animals↗
PubMed1999

The shift of genetic subtypes of Escherichia coli O157:H7 isolates from cattle.

A total of 46 Escherichia coli O157:H7 isolates were obtained from sequential faecal samples from seven cattle collected over periods of 2 months. Nine closely related genetic subtypes, determined by pulsed-field gel electrophoresis types using three kinds of restriction endonuclease were observed among the isolates. Distinguishable, but closely related genetic subtypes can be isolated from one farm, or from one cow, should be considered when undertaking an epidemiological survey.

Animals↗
PubMed1999

Simultaneous up-regulation of urokinase-type plasminogen activator (uPA) and uPA receptor by hepatocyte growth factor/scatter factor in human glioma cells.

Several lines of evidence indicate that hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, may play an important role in progression of human glioma. In this study, effects of HGF/SF on urokinase- type plasminogen activator (uPA)-mediated proteolysis network were examined in c-Met-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of uPA proteins accompanying increased transcription of uPA mRNA in a dose dependent fashion. The levels of uPA receptor (uPAR) mRNAs were also elevated simultaneously upon HGF/SF stimulation, and the cell-surface associated uPA activity was also elevated by the treatment. Since concomitant expression of HGF and its receptor c-Met are frequently observed in malignant gliomas, these results suggest that HGF/SF participates in invasive process of malignant glioma cells not only by its motility-stimulating activity but also through enhanced degradation of the extracellular matrix induced by autocrine activation of uPA proteolysis network.

Central Nervous System Neoplasms↗