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N Ohara

Publications and source records attributed to N Ohara.

At least 55 records · Page 3Linked to original sources
PubMed2001

Adenovirus-mediated ex vivo gene transfer of basic fibroblast growth factor promotes collateral development in a rabbit model of hind limb ischemia.

Adenovirus-mediated ex vivo gene transfer of basic fibroblast growth factor (bFGF), a new strategy for the treatment of chronic vascular occlusive disease, was examined in a rabbit model of hind limb ischemia. The left femoral artery was completely excised to induce an ischemic state in the hind limb of male rabbits. Simultaneously, a skin section was resected from the wound, and host fibroblasts were cultured. The cultured fibroblasts were infected with adenovirus vector containing modified human bFGF cDNA with the secretory signal sequence (AxCAMAssbFGF) or LacZ cDNA (AxCALacZ). At 21 days after femoral artery excision, the gene-transduced fibroblasts were administered through the left internal iliac artery. The fibroblasts significantly accumulated in the ischemic hind limb, and the AxCAMAssbFGF-treated cells secreted bFGF for less than 14 days without elevation of systemic bFGF level. At 28 days after cell administration, calf blood pressure ratio, angiographic score, capillary density of muscle tissue and blood flow of the left internal iliac artery were determined, and animals with AxCAMAssbFGF-treated cells showed significantly greater development of collateral vessels, as compared with those with AxCALacZ-treated cells. These findings suggest that adenovirus-mediated ex vivo gene transfer of bFGF was effective for improvement of chronic limb ischemia.

Adenoviridae↗
PubMed2001

Leiomyosarcoma arising in a remnant esophagus after esophagectomy: a case report.

We report an extremely rare case of leiomyosarcoma arising from a remnant esophagus. A 52-year-old Japanese man was referred to our hospital for treatment of a tumor arising from the remnant esophagus. Four years earlier, he underwent a subtotal esophagectomy for esophageal squamous cell carcinoma (well differentiated squamous cell carcinoma, T1N0M0 Stage I) located in the lower esophagus. After preoperative studies, partial esophagectomy with laryngeal preservation and reconstruction using a free graft from the jejunum were performed. Histopathological and immunohistochemical examination revealed leiomyosarcoma without metastasis. Immunohistochemical examination showed that most tumor cells were positive for smooth muscle actin and vimentin, but were negative for cytokeratin and S100. The deeply biopsied specimens are helpful for preoperative histological diagnosis. Mitotic activity has been considered an important criterion of malignancy. However, some cases with minimal mitosis in the tumor grow rapidly and were associated with poor prognosis. Therefore, we advocate that the clinical behavior is the only true indication of malignancy. We also provide a review of 64 cases of esophageal leiomyosarcoma reported in the Japanese literature with available data between 1969 and 1999, including the present case, and discuss their clinicopathological features. Asynchronous occurrence of leiomyosarcoma and squamous cell carcinoma in the esophagus is most unusual and has never been reported. Patients with infiltrating type leiomyosarcoma measuring more than 5 cm in diameter tend to have a poor prognosis. Chemotherapy did not exhibit any survival benefits. In the present patient, no recurrence has been noted for 23 months after surgery.

Carcinoma, Squamous Cell↗
PubMed2001

TNF-alpha-mediated activation of HIV-1 LTR in monocytoid cells by mycobacteria.

Mycobacterial infection occurs commonly in patients with acquired immune deficiency syndrome. Incubation of monocytoid cell line U937 cells, which was cotransfected HIV-1 long terminal repeat sequence (LTR) chloramphenicol acetyltransferase (CAT) plasmid and Tat expression plasmid, with Mycobacterium smegmatis, Mycobacterium avium, Mycobacterium bovis BCG and Mycobacterium tuberculosis resulted in enhancement of CAT production, indicating that these mycobacteria could activate LTR in this cell line. The amount of CAT in the cells coexisting with M. smegmatis was higher than that infected with other mycobacteria. The amounts of CAT production in the cells coculturing with M. avium and M. bovis BCG were intermediate. M. tuberculosis slightly stimulated CAT production. The amount of tumor necrosis factor (TNF)-alpha produced by transfected U937 cells was correlated with the amount of CAT production. The interleukin (IL)-1beta and IL-6 levels in the supernatant from coculturing with all species were similar. The antibody to TNF-alpha inhibited CAT production induced by mycobacterial infections. The anti-IL-1beta and anti-IL-6 antibodies, however, scarcely influenced stimulation of LTR by mycobacteria. In addition, U937 cells transfected with full length LTR CAT plasmid showed increased CAT production by activation with mycobacteria, but the cells transfected with mutant LTR CAT constructs from which the nuclear factor (NF)-kappaB binding site was deleted did not show activation. These findings indicated that activation of Mycobacterium-induced LTR CAT is NF-kappaB dependent. These findings suggested that activation of HIV-1 LTR by mycobacteria was mainly mediated by NF-kappaB-induced secondary release of cytokine TNF-alpha.

Cell Line↗
PubMed2000

Expression of connective tissue growth factor in cartilaginous tumors.

BACKGROUND: Connective tissue growth factor (CTGF) predominantly is expressed in hypertrophic chondrocytes and its specific receptors are demonstrated on chondrocytic cells. Therefore, CTGF may be involved in the proliferation and/or differentiation of cartilage cells. In the current study, CTGF expression was examined both in chondrosarcoma and enchondroma to clarify the relation between the expression of CTGF and the grade of malignancy. METHODS: The expression of CTGF and proliferating cell nuclear antigen (PCNA) were analyzed immunohistochemically in 34 cartilaginous tumor specimens. Eighteen tumors were determined to be chondrosarcoma including 8 Grade 1 tumors, 6 Grade 2 tumors, and 4 Grade 3 tumors. The percentage of CTGF positive and PCNA positive cells was quantified using at least 500 cells. RESULTS: CTGF was expressed in 70.1% of enchondroma cells, 84.0% of Grade 1 chondrosarcoma cells, 53.7% of Grade 2 tumor cells, and 26.8% of Grade 3 tumor cells (rho = -0.501; P = 0.0053). In chondrosarcoma cases, CTGF expression was correlated closely with tumor grade (rho = -0.920; P = 0.0001). There was a strong correlation between PCNA expression and tumor grade (rho = 0.907; P < 0.0001) and a strong negative correlation between CTGF and PCNA expression (rho = -0.493; P = 0.0061). In chondrosarcoma cases, patients with high expression of CTGF (>/= 30%) showed higher overall survival compared with those with low expression (< 30%) (P = 0.004). CONCLUSIONS: The current study revealed a correlation between the histologic grade of chondrosarcoma and prognosis, and the concomitant association between CTGF immunostaining and tumor grade and prognosis. Therefore, immunohistochemical staining with CTGF is a useful procedure for assessing the tumor grade and clinical course in patients with chondrosarcoma.

Adolescent↗
PubMed2000

Blood coagulation and osmolar tolerance of erythrocytes in stroke-prone spontaneously hypertensive rats given rapeseed oil or soybean oil as the only dietary fat.

The life-span of stroke-prone spontaneously hypertensive rats (SHRSP) has been reported to become shorter by ingestion of some vegetable oils, including rapeseed oil, when given as the sole dietary fat. The present study was undertaken to examine if the ingestion of rapeseed (canola) oil affects blood coagulating time and erythrocyte membranes. Namely, SHRSP were orally given canola oil or soybean oil as the only dietary fat (10% of diet) for 4 weeks. After the 4-week feeding, activated partial thromboplastin time (APTT) in the canola oil group (19.9+/-0.5 s, N=8) was significantly shorter than that in the soybean oil group (21.6+/-0.6 s, N=8, P<0. 05), though there were no between-group differences in plasma Ca(2+), platelet density and platelet aggregation. Erythrocytes from the canola oil group were less tolerant to low osmotic pressure than those from soybean oil group; the EC(50) values for NaCl concentration to cause hemolysis were 0.42+/-0.004 and 0.40+/-0.005% in the canola oil and the soybean oil groups, respectively (N=10, P<0.01). The canola oil-induced shortening of blood coagulation time and increased fragility in erythrocyte membranes may have relevance to the promotion of strokes in SHRSP.

Animals↗
PubMed2000

Dietary intake of rapeseed oil or soybean oil as the only fat nutrient in spontaneously hypertensive rats and Wistar Kyoto rats - blood pressure and pathophysiology.

Spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) rats were fed a diet containing 10% rapeseed (canola) oil or soybean oil as dietary fat, and given drinking water containing 1% NaCl for 26 weeks. From the 10th week and later, systolic blood pressure in the canola oil group became higher than that in the soybean oil group in each strain. The 26-week feeding of canola oil increased plasma lipids and the neutrophil counts, and decreased the platelet counts. In the canola oil group the heart and kidney tended to become heavier with sporadically found histologic lesions. Acetylcholine- and nitroprusside-induced dilating responses of isolated aortic rings and norepinephrine- and veratridine-induced increases in vascular tone of isolated perfused mesenteric arteries were not different between the two groups in each strain. These results demonstrate that canola oil intake as the only dietary fat elevates blood pressure of the rat provided with drinking water containing 1% NaCl through mechanisms other than blunt dilating response of the blood vessel due to dysfunction of the endothelium or vascular smooth muscle, the augmented response to norepinephrine in the arteries and the increased amount of norepinephrine in the sympathetic nerve endings. The lesions in the heart and kidney in SHR may be related to a strain-specific peripheral vascular deterioration which was disclosed by the extremely high blood pressure in the canola oil group.

Acetylcholine↗
PubMed2000

Inhibition of multiplication of Mycobacterium leprae in mouse foot pads by recombinant Bacillus Catmette-Guérin (BCG).

Immunization of mice with recombinant Mycobacterium bovis Bacillus Calmette-Guérin (rBCG) which over-produces a putative protective antigen candidate, the A component of antigen 85 complex (Ag85A), reduced the multiplication of Mycobacterium leprae in the foot pads of mice. The inhibition by this rBCG (rBCG/85A) was more evident than that with parental BCG. Repeated rBCG/85A immunization significantly could reduce M. leplae multiplication in mice. This is first report of rBCG to control mycobacterial infection in animal model. Therefore, rBCG technique may be useful for the development of a more effective mycobacteria vaccine.

Acyltransferases↗
PubMed2000

Identification and characterization of the ribosome-associated protein, HrpA, of Bacillus Calmette-Guérin.

HrpA was found as a ribosome-associated protein which appeared in heat-stressed Mycobacterium bovis Bacillus Calmette-Guérin. Here, we have studied the function of HrpA in vitro. HrpA is a heat shock protein belonging to a small heat shock protein family. The putative molecular mass was 17784.86 kDa. Recombinant HrpA formed large complexes of nonamer or dodecamer. HrpA prevented the aggregation of enzymes under heat shock conditions, and it formed stable complexes with partially denatured enzymes. HrpA was induced temporarily by oxygen repletion after anaerobic condition.

Amino Acid Sequence↗
PubMed2000

Adverse outcome following transfemoral endovascular stent-graft repair of an abdominal aortic aneurysm in a patient with severe liver dysfunction: report of a case.

We describe herein the case of a patient with severe liver failure in whom an abdominal aortic aneurysm (AAA) extending to the right iliac artery was diagnosed. Because the risk of performing a standard open repair was considered too high in this patient, the aneurysm was uneventfully repaired using a technique of transfemoral endovascular stent-grafting with femorofemoral bypass and occlusion of the left common and right internal iliac arteries. Unfortunately, multiorgan failure associated with adult respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC) suddenly developed on postoperative day (POD) 2 and the patient died on POD 9. Thus, although endovascular stent-grafting is generally assumed to be less invasive and therefore feasible for high-risk patients, patients with severe liver dysfunction may not be suitable candidates.

Aged↗
PubMed2000

Thirteen-week dietary intake of rapeseed oil or soybean oil as the only dietary fat in Wistar Kyoto rats-change in blood pressure.

Wistar Kyoto (WKY) rats were fed a diet containing 10% rapeseed (canola) oil or soybean oil as the only dietary fat for 13 weeks. From week 5 of feeding, systolic blood pressure of the canola oil group became higher than that of the soybean oil group. The 13-week canola oil intake increased plasma levels of Na(+) and lipids, and decreased the level of K(+) compared to those in the soybean oil group. The canola oil group also showed a high density of neutrophils and a low density of platelets compared to the soybean oil group. Moreover, the activities of catalase and superoxide dismutase in the hepatic cytosol were depressed in the canola oil group. The mechanisms for the higher blood pressure are unclear. However, an increase in body fluid via activation of Na(+) pump or Na(+), K(+)-ATPase and/or a blunt endothelium-dependent vasodilation by increased superoxide might have relevance to the elevated blood pressure. The increased plasma lipids and the changes in the densities of platelets and neutrophils appear not to be critical in WKY rats. However, these would tend to promote peripheral vascular lesions in the strains, such as spontaneously hypertensive rats and stroke-prone spontaneously hypertensive rats, which are prone to present atheroscrelotic vascular injury.

Animals↗
PubMed2000

Fibronectin-binding proteins secreted by Mycobacterium avium.

Mycobacterium avium is an intracellular pathogen and a major opportunistic infectious agent observed in patients with acquired immune deficiency syndrome (AIDS). Fibronectin is an extracellular matrix protein and is a virulence factor for several extracellular pathogenic bacteria binding to mucosal surfaces. We investigated the fibronectin (FN)-binding proteins in the culture filtrate of M. avium by two-dimensional electrophoresis (2DE). Proteins in Sauton medium of M. avium after 3 weeks were separated by 2DE. The proteins were blotted onto polyvinylidene difluoride membrane and incubated with FN. FN-binding proteins were detected by Western blotting using anti-FN antibody. FN bound to five spots (33 kDa, 32 kDa, 31 kDa, 30 kDa and 25 kDa). N-terminal amino acids of these were determined. The 33 kDa spot corresponded to antigen 85 (Ag 85) C. The 32 and 31 kDa spots were either Ag 85 A or Ag 85 B. The 30 kDa spot corresponded to Ag 85 B of M. avium. The 25 kDa spot corresponded to MPA51 (M. avium MPB51). Thus, FN bound exclusively to the Ag 85 complex and MPA51.

Amino Acid Sequence↗
PubMed2000

Ten years' experience of aortic aneurysm associated with systemic lupus erythematosus.

BACKGROUND: aortic aneurysm is a rare but life-threatening cardiovascular complication in patients with systemic lupus erythematosus (SLE). The purpose of this study was to clarify the characteristic clinical features and the pathological mechanism of aneurysmal formation in these patients. METHODS: among 429 patients operated on for abdominal aortic aneurysm (AAA) during the past 10 years, five cases with SLE were treated surgically. Their clinical data were reviewed, and the resected aneurysmal wall of the five patients was also examined histologically. RESULTS: the mean age of the patients with SLE was 55 years, which was statistically younger than that of the other patients (mean 77 years, s.d. 7.9, p <0.05). They had received long-term corticosteroid therapy for the treatment of SLE for a mean of 23 years. Histologically, destruction of the medial elastic lamina was characteristic. Four patients had no complications in the postoperative follow-up period (mean 4 years), while the remaining patient died of rupture of a dissecting aneurysm two years after operation. CONCLUSION: prolonged steroid therapy may play a major role in accelerating atherosclerosis, which can result in aortic aneurysmal enlargement, possibly together with primary aortic wall involvement and/or vasculitic damage in patients with SLE.

Adrenal Cortex Hormones↗
PubMed2000

Increased incidence of follicular lymphoma in the duodenum.

The incidence of indolent lymphomas in the lymph nodes and extranodal regions is quite different. Follicular lymphoma (FL) is most common in the nodes, and it seems to be least common in the gastrointestinal (GI) tract, where mucosa-associated lymphoid tissue lymphoma arises most frequently. The authors report that the incidence of FL is unexpectedly high in the duodenum compared with other portions of the GI tract. FL was detected in only eight of 222 cases of GI lymphoma (3.6%). However, five cases of FL arose in the duodenum, which accounted for 38.5% of 13 duodenal lymphomas. Only in two patients did FL arise in either the stomach or the colorectum, and in the remaining patients FL was widespread with lymphomatous polyposis. Duodenal FL was composed of neoplastic follicles with small cleaved cells in dominance, and the immunophenotype of the lymphoma cells was CD10+, BCL-2+, CD20+, CD75+, CD79+, CD3-, CD5-, cyclin D1-, CD23-, and CD45RO-. All the patients were women age 37 to 66 years (average age, 52.4 yrs). In all patients the lymphoma was present around the ampulla of Vater, and four of five patients showed multiple small-size polyps. Although lymphoma cell infiltration was confined to the submucosa in the four patients examined, the regional lymph nodes were involved partially in two patients without distant metastasis. All patients are alive at 2 to 50 months of follow up (average, 27 mos), which is comparable with the prognosis for indolent nodal lymphomas. These results suggest that the duodenum has a distinct background of histogenesis of the lymphomas and that biopsy specimens from the duodenum with multiple polyps should be examined carefully.

Adult↗
PubMed2000

Increase in blood pressure with enhanced Na+, K+ -ATPase activity in stroke-prone spontaneously hypertensive rats after 4-weeks intake of rapeseed oil as the sole dietary fat.

Twenty stroke-prone spontaneously hypertensive rats were divided into 2 groups of 10 animals each, and fed a defatted diet and orally administered rapeseed (canola) oil or soybean oil at 10 (w/w)% of the consumed diet once a day for 4 weeks. At the 4th week of administration, the systolic blood pressure in the canola oil group was higher (235 +/- 2 mmHg, mean +/- S.E.M., N=10) than that in the soybean oil group (225 +/- 4 mmHg, N=10, P<0.05). In isolated, perfused mesenteric bed from these rats, the increase in perfusion pressure by norepinephrine, ATP, arachidonic acid, endothelin-1, angiotensin II or serotonin showed no between-group differences. There were also no between-group differences in the production of thromboxane A2 and prostaglandin 12 in the outflow by arachidonic acid injection. On the other hand, in the isolated aortic ring from the canola oil group, developed tension in potassium-free solution was enhanced with activation of Na+, K+ -ATPase. These results suggest that canola oil intake as the sole dietary fat increases systolic blood pressure of stroke-prone spontaneously hypertensive rats. The changes in vascular responsiveness to vasoconstrictors and production of prostanoids are unlikely to have relevance to the elevation of blood pressure. However, altered Na+, K+ -ATPase activity may play a role in the promotion of blood pressure elevation.

6-Ketoprostaglandin F1 alpha↗
PubMed2000

Sequence analysis and variation of EBNA-1 in Epstein-Barr virus-related herpesvirus of cynomolgus monkey.

OBJECTIVES: The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1) is an important protein for immortalization and tumorigenesis of infected cells. EBNA-1 gene variants may play a role in tumorigenesis. We determined the nucleotide and amino acid (aa) sequences of EBNA-1 in EBV-related herpesviruses from cynomolgus monkeys (cynomolgus-EBV) which induced malignant lymphomas in its natural host and in rabbits, and compared them with sequences of EBV and other lymphocryptoviruses (LCVs). METHODS: Polymerase chain reaction and direct sequencing methods were performed using extracted DNA from cynomolgus-EBV-infected cell lines. RESULTS: The amino acid sequences of cynomolgus-EBV EBNA-1 from two cell lines (Si-IIA: 588 aa; Ts-B6: 619 aa) which are antigenically cross-reactive to human EBV EBNA-1 showed homology with human EBV (Si-IIA: 53%; Ts-B6: 58%) and other LCVs from baboons (54 and 52%) and rhesus monkeys (60 and 58%), especially in the C-terminal unique domain. Homology of the EBNA-1 sequence between Si-IIA and Ts-B6 was 92%. The sequence difference between EBV and the related LCVs was manifested mainly in the length of the internal repeat 3-corresponding region, which contains serine in the glycine/alanine repeat region of nonhuman LCVs. CONCLUSION: Sequence variation of cynomolgus-EBV EBNA-1 from different cell lines was observed. However, their sequences show a relatively high homology with human EBV and share the common features of EBNA-1 of EBV and other LCVs.

Amino Acid Sequence↗
PubMed2000

Impaired intestinal active calcium absorption and reduction of serum 1alpha, 25(OH)2D3 in streptozotocin-induced diabetic pregnant rats with hypocalcemia in their fetuses.

PURPOSE: The effects of maternal diabetes mellitus on fetal hypocalcemia were studied in streptozotocin-induced diabetic rats. MATERIALS AND METHODS: Experiments were performed using Wistar rats rendered diabetic with streptozotocin. Treatment with insulin was started in six diabetic pregnant rats after diabetes induction. On day 21 of gestation, cesarean section was performed and serum ionized calcium, parathyroid hormone and 1alpha, 25-dihydroxyvitamin D3 were measured and the active intestinal calcium absorption was measured in mother rats using the everted gut sac technique. RESULTS: In untreated diabetic pregnant rats, serum 1alpha, 25-dihydroxyvitamin D3 and the active intestinal calcium absorption were significantly decreased, and the placental calcium transfer was disturbed compared with the control and insulin-treated groups. Furthermore, serum ionized calcium levels were markedly reduced in fetuses from untreated diabetic pregnant rats. However, these abnormalities of calcium metabolism in untreated diabetic rats could be corrected by treatment with insulin. CONCLUSIONS: These data indicate that diabetes mellitus in pregnant rats a contribute to negative calcium homeostasis which is probably related to the development of fetal hypocalcemia.

Animals↗