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N Yamanaka

Publications and source records attributed to N Yamanaka.

At least 37 records · Page 2Linked to original sources
PubMed2001

Detection of endophyte toxins in the imported perennial ryegrass straw.

From 1997 to 1999, 29 cases of disorders were detected in cattle and horses that had been fed ryegrass straw imported from the U.S.A. These animals showed symptoms resembling ryegrass staggers and the clinical signs disappeared after removal of the straw. Endophytic hyphae were detected in the seeds of all straw samples that were responsible for the clinical cases. Lolitrem B concentrations in the straw ranged between 972 and 3740 ppb. Ergovaline concentrations were between 355 and 1300 ppb. Even though the concentrations of lolitrem B were lower than the toxic threshold proposed by Oregon State University in better part of the cases, our observations suggest the possibility that lolitrem B lower than the proposed threshold can bring disorders to sensitive individuals.

Animals↗
PubMed2001

[An experimental study for qualitatively diagnosing stapes lesions by helical 3-dimensional CT].

To evaluate qualitative diagnosis of stapes lesions by 3-dimensional computed tomography (3D-CT) combined with superselective image processing (3D-SS) of stapes, we studied helical 3D-CT on a phantom model of the temporal bone. Two stapes models were used-1 made from the bone filler, Celatite, consistent in bone density but changing in cross sectional area, and the other made from an apacerum rod used in quantitative computed tomography (QCT), consistent in cross sectional area but changing in bone density. These stapes models were put into a skull phantom and analyzed by helical 3D-CT. The influence of the tympanic cavity conditions on CT images of stapes was evaluated by filling the phantom model with Vaseline following 3D selective reconstruction. In all stapes models, lowering the lower CT window width threshold resulted in an enlarged cross-sectional area of the model. The higher the bone density, the lower the increase in cross-sectional area in the image. The stapes model with lower density had greater influence on the imaging by tympanic cavity conditions and was likely to be misdiagnosed as showing higher bone density. Based on the experimental study, 3D-SS by helical 3D-CT appears to be a useful measure for qualitatively diagnosing stapes lesions.

Hearing Loss, Conductive↗
PubMed2001

[Adjuvant GM-CSF cytokine gene therapy for breast cancer].

UNLABELLED: The aim of this study was to examine the enhancement of antitumor immunity of irradiated granulocyte macrophage-colony-stimulating factor (GM-CSF) gene-transduced mouse breast cancer cells. METHODS: BALBMC mouse were vaccinated subcutaneously with saline or irradiated mouse breast cancer cells, BALBMC (1 x 10(6)/mouse), infected or not infected with recombinant adenovirus harboring GM-CSF gene on day-7. Mice were injected with parental cells (1 x 10(5)/mouse) on day 0. RESULTS: No mice vaccinated with irradiated GM-CSF producing BALBMC cells developed a tumor during the observation period of up to 16 weeks, whereas 100% of mice injected with saline developed a tumor. CONCLUSION: Our study demonstrates the feasibility of this immunotherapeutic approach as a novel adjuvant cancer therapy after surgery for breast cancer.

Animals↗
PubMed2001

[Docetaxel was effective as neoadjuvant chemotherapy for patients after failure of trans-arterial neoadjuvant chemotherapy with CEF in 2 cases of advanced breast cancer].

Docetaxel was effective as a second line neoadjuvant chemotherapy after failure of cyclophosphamide, epirubicin and 5-FU (CEF) in 2 cases of breast cancer. In Case 1, 4 cycles of trans-arterial neoadjuvant chemotherapy of docetaxel showed a PR effect after failure of 2 cycles of trans-arterial neoadjuvant chemotherapy with CEF. This patient died of pleuritis carcinomatosa 18 months after surgery for breast cancer (latissimus dorsi muscle myocutaneous flap after radical mastectomy). In Case 2, 6 cycles of neoadjuvant venous drip infusion of docetaxel resulted in a CR effect after failure of 2 cycles of transarterial neoadjuvant chemotherapy with CEF. This patient is alive and disease-free 27 months after the operation for breast cancer (same operation as for Case 1). Docetaxel was effective as neoadjuvant chemotherapy for patients after failure of trans-arterial neoadjuvant chemotherapy with CEF.

Aged↗
PubMed2000

Long-term assessment of serum vitamin B(12) concentrations in patients with various types of orthotopic intestinal neobladder.

OBJECTIVES: Vitamin B(12) deficiency is an important long-term problem after urinary diversion using an intestinal segment. In this study, we examined serum vitamin B(12) concentrations in patients with neobladders constructed from various intestinal segments to determine the anatomic factors important for avoiding vitamin B(12) deficiency. METHODS: Twenty-two patients (19 men and 3 women) had an ileal neobladder (modified Studer type); 9 men had an ascending colonic neobladder (Goldwasser type); 30 patients (24 men and 6 women) had a sigmoid neobladder (modified Reddy type); and 18 (15 men and 3 women) had an ileocolic neobladder (Mainz type). The postoperative follow-up ranged from 3 months to 11 years (mean +/- SD, 3.4 +/- 2.8 years). The serum vitamin B(12) concentration was determined at several points after surgery. RESULTS: No patient with a neobladder fashioned from ascending or sigmoid colon developed a low vitamin B(12) concentration. Of the 18 patients with an ileocolic neobladder, 3 (16.6%) developed decreased serum vitamin B(12) concentrations after 5 to 6 years. Of the 22 patients with an ileal neobladder, 3 (13.6%) developed a low serum concentration of vitamin B(12) between 9 months and 3 years after surgery. No patient developed megaloblastic anemia or neurologic symptoms. CONCLUSIONS: Preservation of the terminal 15 cm of ileum is not sufficient to ensure adequate vitamin B(12) absorption, and thus, preserving the ileal length is important. Use of colonic segments to construct neobladders appears to be preferable to ileal segments to preserve vitamin B(12) absorption.

Aged↗
PubMed2000

Immune response to surface protein A of Streptococcus pneumoniae and to high-molecular-weight outer membrane protein A of Moraxella catarrhalis in children with acute otitis media.

The immune response was evaluated in 11 children with Streptococcus pneumoniae and in 9 children with Moraxella catarrhalis otitis media. The age of the children had a range of 4-32 months. The mean IgG, IgM, and IgA antibody responses to surface protein A (PspA) of S. pneumoniae in sera from children at the acute and convalescent stages were 4864 versus 5831 ng/mL, P<.05, 1075 versus 3752 ng/mL, P<.05, and 67 versus 93 ng/mL, nonsignificant (NS), respectively. The mean IgG, IgM, and IgA antibody responses to the high-molecular-weight outer membrane protein (UspA) of M. catarrhalis in sera from children at acute and convalescent stages were 710 versus 935 mg/mL, NS; 1895 versus 2646 ng/mL, NS; and 121 versus 204 ng/mL, P<.05, respectively. These data show that PspA and UspA are immunogenic in children after otitis media.

Acute Disease↗
PubMed2000

Characterization and identification of (CT)n microsatellites in soybean using sheared genomic libraries.

Three small insert (300 to approximately 600 bp) sheared genomic libraries were constructed by pipetting and DNase I treatment of soybean DNA. About 15,000 clones from each library were screened for CT- simple sequence repeats (CT-SSRs). The CT-SSRs were abundant in the soybean genome at an estimated frequency of approximately one SSR per 110 kb of genomic DNA. Following the sequencing of 129 positive clones, the repeat types and frequency of CT repeats among the positive clones were characterized. Forty-nine primer pairs were designed and preliminarily evaluated for their ability to amplify genomic DNA from a set of six varieties, including parents of a mapping family. Amplified products were analyzed by 10% PAGE. Eighty-eight percent of the designed primers were able to amplify all these genomic DNAs using a single PCR profile of 53 degrees C annealing temperature, of which 22 (45%) were polymorphic in the six varieties, and 14 of them were polymorphic in the parents of the mapping family. The polymorphic primer sets were further assessed for allelic information using DNA from 16 soybean cultivars. The average number of alleles was 4, ranging from 2 to 7 with the highest polymorphism information content value 0.84. Fourteen of these SSRs were mapped, using an existing soybean RFLP map. The findings presented here will advance our understanding of the soybean genome, and assist in the mapping genome and discrimination of closely related varieties of this species.

Chromosome Mapping↗
PubMed2000

Optimal route of administration of mixed endothelin receptor antagonist (TAK-044) in liver transplantation.

It is well known that endothelin-1(ET-1) is a factor involved in the pathogenesis of ischemia-reperfusion injury. This study was undertaken to investigate the optimal route (intravenous vs intraportal) for administering mixed endothelin receptor antagonist (TAK-044) in a liver transplantation. First, in a rat isolated liver cold-perfusion model, the pharmacodynamics of TAK-044 and endothelin-1 (ET) in the liver tissue and the systemic circulation after cold perfusion were compared in the different administration routes. Next, in a rat orthotopic transplantation model, we compared the hepatoprotective effect of TAK-044 among different administration routes. In each model, there were three groups: IV group, intravenous injection of TAK-044 (10mg/kg) immediately before cold perfusion or anhepatic phase; IP group, intraportal administration with cold perfusion solution or with reflush solution for the graft; control group, no treatment. In the cold perfusion model, liver tissue ET level increased to a similar extent after reperfusion in the three groups, and the plasma and liver tissue TAK-044 concentrations after reperfusion were highest in the IV group. However, the increase in plasma ET was also greatest, and therefore, the ratio of liver tissue to plasma TAK-044 was lower in the IV group compared with the IP group. In the transplantation model, elevation of plasma ET was significantly higher in the IV group. Leakage of serum alanine aminotransferase (ALT), sinusoidal narrowing, and cell swelling after grafting were significantly suppressed in the IP group. We conclude that intraportal administration before reperfusion offers more efficient accumulation of TAK-044 in the liver tissue, without harmful systemic elevation of ET, and achieves a hepatoprotective effect on the graft compared with intravenous administration.

Alanine Transaminase↗
PubMed2000

Viral serostatus and coexisting inflammatory activity affect metachronous carcinogenesis after hepatectomy for hepatocellular carcinoma. A further report.

Little data are available regarding the effects of hepatitis virus serostatus and the severity of coexisting chronic inflammation on intrahepatic recurrence after hepatectomy for hepatocellular carcinoma (HCC). We investigated the extent to which these factors modified the prognosis of hepatectomized patients. A total of 274 patients treated in the period January 1981 to December 1996 were divided into three groups: antihepatitis C-positive (HCV; n = 144), hepatitis B surface antigen-positive and HCV antibody (Ab)-negative (HBsAg; n = 106), and HBsAg-negative and HCV Ab-negative (NBNC; n = 20). Positivity for HBV-related antibody in the HCV group was 76%. Histologic grading of inflammatory activity from coexisting hepatitis was determined according to Knodel's histological activity index (HAI) scoring system. Post-hepatectomy crude survival rates and disease-free survival (DFS) rates were compared, according to tumor characteristics, between the three groups. In the patients overall and also in the patients with a single nodular HCC, the HCV group had significantly higher HAI scores and preoperative serum aspartate aminotransaminase (AST) levels than the other two groups. When the patients were limited to those with a single nodular HCC, the crude survival was similar in the three groups with comparable tumor characteristics; however, the DFS was different (NBNC > HBsAg > HCV). When the patients were further limited to those with a single nodular HCC without microscopic extracapsular spread, in whom removal of the tumor was expected to be microscopically complete, the difference in the DFS became more marked. Irrespective of the viral serostatus, better crude and disease-free survivals were observed in the patients with lower AST levels (< or =50 IU/ 1) than in those with higher AST levels (>50IU/l). In contrast, there were no differences in survivals and HAI scores according to the presence or absence of HBV-related antibody in the HCV group. From our univariate analysis, we can conclude that the severity of virally induced inflammation, which was well correlated with viral serostatus, may be a factor that affects intrahepatic recurrence, which is more likely to originate from metachronous carcinogenesis. Prior co-infection of HBV in HCV patients may not be an adverse risk factor for intrahepatic recurrence.

Carcinoma, Hepatocellular↗
PubMed2000

Evolution of and obstacles in surgical treatment for hepatocellular carcinoma over the last 25 years: differences over four treatment eras.

This study was designed to clarify what differences the last 25 years have made in surgical results for patients with hepatocellular carcinoma (HCC). We examined results for 716 hepatectomized patients in four treatment eras: first era (1973-1980; n = 58), second era (1981-1985; n = 155), third era (1986-1990; n = 243), and fourth era (1991-1997; n = 260). Patient background, tumor characteristics, type of hepatectomy, treatment for intrahepatic recurrences, and surgical results in the four eras were compared by univariate analysis to clarify the factors that have contributed to or impeded progress in the surgical treatment of HCC. Although there were no significant chronological differences in liver pathology and surgical resectability, operative mortality was reduced to 2% in the fourth era, from 29% in the first era. With an increasing proportion of early-stage HCCs (TNM, stages I and II), the cumulative survival rate at 5 years improved in the course of the eras in our overall population of patients (12%, 31%, 38%, and 51%, respectively, for the first, second, third, and fourth eras) and in a subset of the population divided according to tumor stage. Also, we found a chronological improvement in the survival rate at 3 years after intrahepatic recurrence (10%, 28%, 36%, and 44%, respectively in the first second, third, and fourth eras). This improvement was associated with the establishment of an early detection program for intrahepatic recurrences. However, the recurrence rate was similar in any subset of the population through the four eras. Although this univariate study could not determine independent factors that contributed to the chronological progress in results for HCC surgery in the four eras, it is conceivable that the establishment of indication criteria for hepatectomy, an early detection program for primary and recurrent lesions, and the introduction of multimodal treatment for recurrence were contributory factors in this improvement. A strategy for alleviating the frequent recurrences originating from posthepatectomy metachronous carcinogenesis remains to be established.

Analysis of Variance↗
PubMed2000

Does topical cooling alleviate ischemia/reperfusion injury during inflow occlusion in hepatectomy? Results of an experimental and clinical study.

This study was undertaken to evaluate whether topical cooling can alleviate ischemia/reperfusion injury, after continuous inflow occlusion during hepatectomy. Using a canine model of 70% partial liver ischemia (60 min), alteration in the subcellular (cytoplasm, mitochondria, nucleus) elements calcium, sodium, potassium, and chloride, and liver functions following reperfusion were compared between control livers and livers subjected to topical cooling down to 23 degrees +/- 4.9 degrees C by seeding ice slush over the ischemic lobe. The elements were determined by X-ray microanalysis using liver biopsy specimens. A similar clinical study was undertaken examining ten patients with hepatocellular carcinoma and chronic liver disease who underwent right-sided segmentectomy under continuous right inflow occlusion, five of whom were given topical cooling and five of whom were not. In the experimental study, postreperfusion worsening of liver function tests was significantly suppressed in the cooling group, which was associated with the suppression of subcellular Ca, Na, and Cl increases and K decreases after reperfusion. In the clinical study, the occlusion time was significantly longer in the hypothermic patients than in the normothermic patients, but no significant differences in postoperative liver function or postischemic increases in Ca, Na, or Cl and decreases in K were observed. These experimental and clinical findings suggest that topical cooling alleviates ischemic insult and enhances safe prolonged inflow occlusion.

Aged↗
PubMed2000

Intratumoral genomic heterogeneity in human hepatocellular carcinoma detected by restriction landmark genomic scanning.

BACKGROUND/AIMS: One of the unique features of advanced hepatocellular carcinoma (HCC) is the morphological heterogeneity in a single tumor nodule. In order to investigate the intratumoral genomic heterogeneity of HCC, we performed Restriction Landmark Genomic Scanning (RLGS), which allows genomic DNAs to be surveyed at approximately 2000 landmark sites in a single 2-dimensional gel electrophoresis. METHODS: RLGS profiles of two regions from a single HCC nodule in six patients were compared with non-tumorous liver tissue. Four HCCs consisting of moderately-differentiated cells were separated into several small parts by thin fibrous septa, but not encapsulated. DNA samples were obtained from both parts of these so-called "nodule-in-nodule" HCC. Two HCCs consisting of well-differentiated cells which did not have a definite partition appeared pathologically homogeneous, and two independent regions of the HCC were used for the analysis. RESULTS: All six HCCs demonstrated different RLGS profiles (in total about 160 different spots) from the corresponding non-tumorous liver, and the number of different spots was greater in the 4 moderately-differentiated nodule-in-nodule HCCs (39-68 spots) than in the 2 well-differentiated homogeneous HCCs (6 and 3 spots). RLGS profiles of the two parts were different to each other in all 4 nodule-in-nodule HCCs. On the other hand, two other homogeneous HCCs showed the same RLGS profiles in the two regions. CONCLUSION: Thus, intratumoral genomic heterogeneity was demonstrated in the advanced HCC samples, and the genomic alterations may relate to the progression of HCC.

Aged↗
PubMed2000

Middle ear adenoma with neuroendocrine differentiation.

The lining of the middle ear cleft is normally a thin modified respiratory type mucosa. Normal mucosa of the middle ear is devoid of salivary type seromucous glands. Middle ear adenoma is a rare tumor that seems to be derived from the middle ear mucosa. This tumor has been previously described under a variety of names because of its different nature and biological behavior. We herein report a case of middle ear tumor that shows adenomatous and neuroendocrine features. A 64-year-old woman presented with a history of hearing loss, tinnitus and stuffy feeling of the right ear. The patient was treated two times for ear polyp. She finally underwent a tympanomastoidectomy and there was no evidence of recurrence 18 months after the procedure. Histopathological examination displayed cuboidal and columnar cells, arranged as glands, trabeculae and solid sheets. Neuroendocrine differentiation was revealed by immunohistochemical staining with polyclonal antibodies against neuron specific enolase and chromogranin antigens.

Adenoma↗