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N Yamada

Publications and source records attributed to N Yamada.

At least 19 recordsLinked to original sources
PubMed2006

Glucose utilization in the inferior cerebellar vermis and ocular myoclonus.

In a patient with symptomatic ocular myoclonus, the authors observed the regional cerebral metabolic rate of glucose use (rCMRGlu) before and after successful treatment with clonazepam. Even after the symptoms resolved, the rCMRGlu in the hypertrophic olive increased persistently, whereas that in the inferior cerebellar vermis contralateral to the hypertrophic olive decreased. The inferior cerebellar vermis, belonging to the vestibulocerebellar system, may be associated with the generation of symptomatic ocular myoclonus.

Aged, 80 and over↗
PubMed2006

Pulse-spray pharmacomechanical thrombolysis for proximal deep vein thrombosis.

OBJECTIVE: The aim of this study was to evaluate the efficacy, safety, and feasibility of pulse-spray pharmacomechanical thrombolysis to treat proximal deep vein thrombosis (DVT) in conjunction with the placement of a non-permanent IVC filter. METHODS: We studied 31 consecutive patients with acute proximal DVT defined as the inferior vena cava (IVC), iliac vein and/or femoral vein, who were diagnosed using duplex ultrasonography and/or contrast venography. All were treated with pulse-spray urokinase. Early success was assessed by comparing the pre- and post-treatment venographic severity score. Non-permanent IVC filters were used to reduce the risk of pulmonary thromboembolism. RESULTS: The average total urokinase dose was 1.71 million IU (range: 0.72-3.6 million IU) and the average duration of therapy was 2.4 days. The average percentage of thrombus lysed was 85% (range: 22-100%). A large thrombus trapped by the filter was detected using cavography before extraction of the filter in one patient. There was no major treatment-related adverse event. CONCLUSION: The combination of pulse-spray pharmacomechanical thrombolysis and the prophylactic use of a non-permanent IVC filter was a safe and effective approach for treating acute proximal DVT.

Adult↗
PubMed2006

Expression and role of MHC class I-related chain in myeloma cells.

BACKGROUND: The molecular mechanism of natural killer (NK) cell cytotoxicity to myeloma cells remains unclear. We investigated whether MHC class I-related chain (MIC), a ligand of NKG2D that is an activating NK cell receptor, is involved in the cytotoxicity of NK cells toward myeloma cells, and examined the effects of various drugs on the cytotoxicity. METHODS: Two human myeloma cell lines and fresh myeloma cells from 10 patients were used. MIC expression was examined by flow cytometry and reverse transcription (RT)-PCR. NK cell cytotoxicity was examined using a 51Cr-release assay. The effects of various drugs, including thalidomide, all-trans retinoic acid, dexamethasone, IFN-alpha and incadronate, on the MIC expression and NK cell cytotoxicity were examined. RESULTS: MIC was highly expressed on the human myeloma cell lines U266 and RPMI-8226 and in myeloma cells of one of 10 patients examined. MIC expression on these cells was not changed by various drugs except IFN-alpha, by which MIC expression was down-regulated. Although MIC and HLA class I molecules were similarly expressed at high levels on both cell lines, U266 was sensitive to NK cells whereas RPMI-8226 was not. Furthermore, cytolysis by NK cells was not inhibited by the addition of anti-MIC Ab or decreased expression of MIC caused by IFN-alpha. DISCUSSION: MIC plays a role in the cytolysis by NK cells in multiple myeloma.

Angiogenesis Inhibitors↗
PubMed2006

Elevated levels of soluble fibrin or D-dimer indicate high risk of thrombosis.

BACKGROUND: Fibrin-related markers such as soluble fibrin (SF) and D-dimer are considered useful for the diagnosis of thrombosis. However, the evidence for diagnosis of thrombosis by fibrin-related markers is not well-established. OBJECTIVE: To evaluate the cutoff values of D-dimer and SF in the diagnosis of thrombosis. PATIENTS AND METHODS: Plasma concentrations of SF and D-dimer were measured in 784 inpatients suspected of having thrombosis between 1 August 2003 and 31 December 2004, and then correlated with thrombosis. RESULTS AND CONCLUSIONS: Plasma concentrations of D-dimer and SF were significantly higher in patients with disseminated intravascular coagulation (DIC), deep vein thrombosis (DVT) and cerebral thrombosis, compared with those in patients without thrombosis. When cutoff values of > 3.0 microg mL(-1) for D-dimer and > 6.0 microg mL(-1) for SF were used for the diagnosis, more than 50% of patients (with the exception of liver transplant patients and postoperative patients) had thrombosis. Receiver operating characteristic analysis showed that SF was more useful than D-dimer for the diagnosis of thrombosis (i.e. DVT and DIC). The cutoff value of D-dimer (7.87 microg mL(-1)) was the same for DVT and DIC, while that of SF was slightly lower for DVT (7.05 microg mL(-1)) than for DIC (8.60 microg mL(-1)). Our findings suggest that high levels of plasma fibrin-related markers reflect high risk for thrombosis.

Aged↗
PubMed2006

Upflow anaerobic sludge blanket (UASB) treatment of supernatant of cow manure by thermal pre-treatment.

Upflow anaerobic sludge blanket (UASB) methane fermentation treatment of cow manure that was subjected to screw pressing, thermal treatment and subsequent solid-liquid separation was studied. Conducting batch scale tests at temperatures between 140 and 180 degrees C, the optimal temperature for sludge settling and the color suppression was found to be between 160-170 degrees C. UASB treatment was carried out with a supernatant obtained from the thermal treatment at the optimal conditions (170 degrees C for 30 minutes) and polymer-dosed solid-liquid separation. In the UASB treatment with a COD(Cr) loading of 11.7 kg/m3/d and water temperature of 32.2 degrees C, the COD(Cr) level dropped from 16,360 mg/L in raw water to 3,940 mg/L in treated water (COD(Cr), removal rate of 75.9%), and the methane production rate per COD(Cr) was 0.187 Nm3/kg. Using wastewater thermal-treated at the optimal conditions, also a methane fermentation treatment with a continuously stirred tank reactor (CSTR) was conducted (COD(Cr) in raw water: 38,000 mg/L, hydraulic retention time (HRT): 20 days, 35 degrees C). At the COD(Cr) loading of 1.9 kg/m3/d, the methane production rate per COD(Cr), was 0.153 Nm3/kg. This result shows that UASB treatment using thermal pre-treatment provides a COD(Cr), loading of four times or more and a methane production rate of 1.3 times higher than the CSTR treatment.

Anaerobiosis↗
PubMed2006

Successful treatment of hepatitis B virus-associated membranous nephropathy with lamivudine.

We present a case of chronic hepatitis B with membranous nephropathy, that was improved by lamivudine treatment. A 37-year-old man was admitted to our hospital for the evaluation of proteinuria. He was diagnosed as having chronic glomerulonephritis associated with chronic hepatitis B. Histopathological findings of the renal biopsy specimen indicated membranous nephropathy. He suffered from nephrotic syndrome associated with leg edema, which was parallel to the exacerbation of hepatitis. Lamivudine was started for the treatment of hepatitis, which caused the disappearance of serum hepatitis B virus DNA and the normalization of ALT level in 4 weeks. Additionally, proteinuria disappeared 120 weeks after the treatment was started. Lamivudine treatment may remit HBV-associated nephropathy.

Adult↗
PubMed2006

[Surgical strategy for critical aoritc stenosis with small aortic annulus in the elderly patients].

BACKGROUND: There are an increasing number of elderly patients with critical aortic stenosis. This study was performed to evaluate the surgical outcome of aortic valve surgery for elderly patients with aortic stenosis. METHODS: Eleven patients aged over 75 years old (mean 79.7 +/- 4.4) underwent aortic valve replacement with stented bioprosthesis from May 2001 to August 2004. All of the patients had a history of congestive heart failure, syncope, or angina pectoris with multiple medical problems including renal dysfunction, diabetes mellitus, cerebral infarction, or coronary artery disease. The New York Heart Association (NYHA) classification ranged II to IV (mean 2.8 +/- 0.7). Their logistic Euro score ranged from 2.56 to 41.61 (mean 8.6 +/- 10.9). The concomitant procedures were annular enlargement in 2 and coronary artery bypass grafting (CABG) in 3 patients. RESULTS: All patients tolerated these procedures well and were discharged except 1 patient who died from arrhythmia on the postoperative day 14. Postoperative echocardiogram after 3 months showed satisfactory decrease in peak left ventricular-aortic pressure gradient as well as left ventricular mass regression. All surviving patients are in NYHA class I. CONCLUSIONS: Aortic valve replacement provided satisfactory results for elderly patients. Surgical treatment should be considered even for the elderly patients with critical aortic stenosis under meticulous perioperative management.

Aged↗
PubMed2005

Quantitative analysis of the effect of probenecid on pharmacokinetics of 99mTc-mercaptoacetyltriglycine in dogs.

Effect of probenecid on pharmacokinetics of 99mTc-mercaptoacetylytriglycine (99mTc-MAG3) in dogs was investigated before (control), and after 15 min and 24 h of i.v. injection of probenecid (20 mg/kg). Plasma concentration-time profiles of 99mTc-MAG3 were described with a two-compartment open model. Plasma 99mTc-MAG3 clearances (Clp, ml/min/kg) were 7.9 +/- 0.5, 3.3 +/- 0.5 and 4.8 +/- 1.3 in control, 15 min and 24 h after probenecid administration respectively. Similarly, the biological half-lives at elimination phase (t(1/2), h) were 0.61 +/- 0.09, 0.79 +/- 0.11 and 0.74 +/- 0.12, and volumes of distribution at steady state (Vdss, L/kg) were 0.29 +/- 0.04, 0.20 +/- 0.05 and 0.25 +/- 0.06 respectively. The prolonged biological half-life and decreased Vdss decreased Clp significantly. Clp was a function of plasma probenecid concentration based on Michaelis-Menten kinetics. The maximum Clp inhibition (Imax) by probenecid and the plasma probenecid concentration that induced 50% of Imax (I50) were estimated to be 72 +/- 12% and 13 +/- 8 microg/ml respectively. This means that the rest (about 28%) of the Clp is not blocked by probenecid alone, suggesting the possibility of another route(s) of elimination or renal transporters which are independent from probenecid. Moreover, inter-species correlation between Clp of 99mTc-MAG3 and body weight are discussed.

Animals↗
PubMed2005

Inactivation of swmA results in the loss of an outer cell layer in a swimming synechococcus strain.

The mechanism of nonflagellar swimming of marine unicellular cyanobacteria remains poorly understood. SwmA is an abundant cell surface-associated 130-kDa glycoprotein that is required for the generation of thrust in Synechococcus sp. strain WH8102. Ultrastructural comparisons of wild-type cells to a mutant strain in which the gene encoding SwmA has been insertionally inactivated reveal that the mutant lacks a layer external to the outer membrane. Cryofixation and freeze-substitution are required for the preservation of this external layer. Freeze fracturing and etching reveal that this additional layer is an S-layer. How the S-layer might function in motility remains elusive; however, this work describes an ultrastructural component required for this unique type of swimming. In addition, the work presented here describes the envelope structure of a model swimming cyanobacterium.

Bacterial Proteins↗
PubMed2005

[Yolk sac tumor of the anterior mediastinum and pulmonary metastases; report of a case].

A 31-year-old female was clinically diagnosed as having a anterior mediastinal yolk sac tumor because of the elevation of the AFP (17,500 ng/ml), a large mass lesion (9 x 5 cm) in the anterior mediastinum and bilateral lung metastases. After 4 courses of chemotherapy with cisplatin (CDDP), etoposide (VP-16) and bleomycin hydrochloride (BLM), the mediastinal mass reduced in size significantly and the serum AFP level reached within normal range. Fluorodeoxyglucose-positron emission tomography (FDG-PET) showed a weak uptake in the mediastinum, accordingly the operation was performed. The tumor was completely removed and there were no viable foci of the tumor in part of the tumor. After the operation, 4 courses of chemotherapy with carboplatin (CBDCA), VP-16 and ifosfamide (IFM) were performed. She is alive without evidence of recurrence in 5 months after operation. It was noticed that the serum AFP is a useful indicator for determing the chance of operation after chemotherapy.

Adult↗
PubMed2004

Overexpression of lipoprotein lipase improves insulin resistance induced by a high-fat diet in transgenic rabbits.

AIMS/HYPOTHESIS: Dysfunctions of lipoprotein lipase (LPL) have been found to be associated with dyslipidaemias, atherosclerosis, obesity and insulin resistance. There are two conflicting hypotheses regarding the roles of LPL in glucose metabolism and insulin resistance. Whether systemically increased LPL activity would be beneficial or detrimental to insulin sensitivity is yet to be resolved. To address this issue, we studied transgenic rabbits overexpressing human LPL transgene. METHODS: LPL transgenic and control rabbits were fed a 10% high-fat diet (HFD) for 16 weeks. To evaluate glucose metabolism, we compared plasma levels of glucose and insulin in transgenic rabbits with control rabbits and performed an intravenous glucose tolerance test. In addition, we measured adipose tissue accumulation in HFD-fed rabbits. RESULTS: Increased LPL activity in transgenic rabbits resulted in a significant reduction of plasma triglycerides and non-esterified fatty acids, but not in basal levels of glucose and insulin. HFD feeding induced an elevation of plasma glucose levels accompanied by hyperinsulinaemia in control rabbits, but was significantly inhibited in transgenic rabbits. The intravenous glucose tolerance test showed that transgenic rabbits had faster glucose clearance associated with lower levels of insulin secretion than control rabbits. In addition, there was a significant reduction of body adipose tissue in transgenic rabbits compared with in control rabbits fed an HFD. Scanning electron microscopic examination revealed that adipocytes in transgenic rabbits were predominately small cells. CONCLUSIONS/INTERPRETATION: Our results showed that systemically increased LPL activity improves insulin resistance and reduces adipose accumulation in transgenic rabbits, indicating that systemic elevation of LPL may have potential benefits for the treatment of insulin resistance and obesity.

Adipocytes↗
PubMed2004

Combination of transconjunctival and endonasal-transantral approach in the repair of blowout fractures involving the orbital floor.

In the repair of orbital blowout fractures through eyelid or conjunctival incision, it is difficult to see the posterior edge of the fracture and the condition of the herniated tissue before reduction of the orbital contents. Prolapsed orbital tissue or infraorbital nerve and vessels may therefore be damaged in the reduction. The recently advocated combination of traditional transconjunctival approach and endoscopic transantral approach allows reduction and reconstruction under clear endoscopic vision without a facial skin incision. We modified this technique to make it less invasive and applied it to the repair of orbital blowout fractures involving the orbital floor. The use of a 70-degree straight endoscope through an enlarged ostium as for functional sinus surgery allowed clear sight of the roof of the antrum. During the repair of the orbital floor through a transconjunctival approach, reduction and reconstruction was assisted from the antrum. Twelve cases of fresh blowout fractures were treated with this approach. There were seven male and five female patients. Mean age was 23.5 years. Causes of injuries were fights, motor vehicle or bicycle accidents, and sports. Patients with concomitant fractures involving the orbital rim were excluded. Persistent diplopia was present in eight cases and enophthalmos of more than 2 mm was detected in five cases preoperatively. The average intervals from injury to surgery was 22.8 days.Exploration, reduction and reconstruction of the orbital floor fractures were precisely performed with this procedure. Large orbital floor defects were reconstructed with silicone sheets, thin iliac bone grafts or nasal septal cartilage. In all eight cases that showed diplopia, ocular movement recovered and symptomatic diplopia disappeared after surgery. Enophthalmos of more than 2 mm was also improved in all five cases. One early case showed temporary entropion. Transient numbness of the cheek appeared in five cases and temporary maxillary sinusitis recovered in one case. Postoperative infection was not observed.This method provides visualisation of posterior edge of the fracture and the condition of herniated orbital contents before initiation of reduction. Dual manipulation by two surgeons is also possible in reduction and reconstruction of the orbital floor.

Adolescent↗
PubMed2004

Improvement of scopolamine-induced memory impairment by Z-ajoene in the water maze in mice.

Z-ajoene, a major compound containing sulfur in oil-macerated garlic products, exhibited inhibitory effects against scopolamine-induced memory impairment in mice using the Morris water maze test. The effects of Z-ajoene were observed dose-dependently (0.25-25 mg/kg). At the highest dosage, the memory performance of mice was improved compared to normal mice. The acetylcholinesterase (AChE) activity in the brain was reduced by administration of Z-ajoene dose-dependently. However, alliin and diallyl disulfide, organosulfur compounds from garlic, did not improve memory performance nor AChE inhibitory effect. These results suggest that Z-ajoene may act on the cholinergic system and on memory impairment caused by excess activity of AChE.

Acetylcholinesterase↗
PubMed2004

Neuroendocrine differentiation of periodic-acid Schiff and Alcian blue-negative signet-ring cell-like cells and tubular adenocarcinoma cells within a gastric cancer.

A case of a Borrmann type 2 advanced gastric cancer with endocrine differentiation is described. Histologically, the cancer was either composed of cells arranged in a tubular pattern or formed solid nests of various sizes. The tubular pattern was composed of a moderately differentiated tubular adenocarcinoma. The histology showed partial carcinoid tumor-like features. Cancer cells inside solid nests had a signet-ring cell-like appearance. Periodic-acid Schiff (PAS) staining was positive in the cytoplasm of a few of the cells found in the tubular pattern and in the mucus in some lumens and on the apical surface of cells in some lumens, but PAS did not stain cancer cells in the solid nests. Neither cancer cells nor mucus in the lumens were stained with alcian blue. All cancer cells were strongly positive for Grimelius silver stain, and most of the cancer cells stained positively for chromogranin A. Electron microscopic examination showed electron dense neuroendocrine granules in the cytoplasm of cancer cells. Cancer cells were stained positively for pancytokeratin, cytokeratin 8/18 and carcinoembryonic antigen. Muc 1 mucin glycoprotein staining was positive along the cell surfaces of cancer cells, but Muc 2, 5AC and 6 stainings were negative, although Muc 3 stained positively in the cytoplasm of a few cancer cells. The present case is a gastric tubular adenocarcinoma with Muc 1-positive, neutral- and acid mucin-negative signet-ring cell-like cells, which is associated with neuroendocrine differentiation.

Adenocarcinoma↗
PubMed2004

Sex differences in mucosal response to Helicobacter pylori infection in the stomach and variations in interleukin-8, COX-2 and trefoil factor family 1 gene expression.

BACKGROUND: Gastric cancer incidence in men is almost double that in women. We investigated mucosal responses in the stomach against Helicobacter pylori (H. pylori) infections to elucidate the interindividual or sex-related differences, which may in turn be associated with gastric cancer incidence, mucosal changes of stomach as measured by the Sydney System, and interleukin-8, cyclooxygenase-2 and trefoil factor family 1 (TFF1) gene expression. METHODS: An age-, sex-, H. pylori status- and disease-matched case-control study was performed in 574 H. pylori-positive and 225 H. pylori-negative patients selected from 4125 patients with a diagnosis of benign disease of the stomach. Levels of acute and chronic inflammations, atrophy and intestinal metaplasia scored according to the Sydney System were compared by stomach site and by sex. Two biopsy specimens (antral and corpus gastric mucosa) from patients with benign gastric diseases (142 patients; 72 men, 70 women) were analysed for interleukin-8, cyclooxygenase-2 and TFF1 mRNA expression as measured by real-time PCR. RESULTS: Inflammation and activity scores in antrum with H. pylori infection were higher in men, but scores declined according to age. Atrophy and intestinal metaplasia scores in corpus with H. pylori infection appeared more severe in men than in women, especially in older patients. In women, atrophy score increased with increasing age, particularly in postmenopausal H. pylori-negative patients. Interleukin-8 mRNA induction was detected in both antrum and corpus mucosa in H. pylori infection, but sex differences were not found. Response of cyclooxygenase-2 mRNA expression against H. pylori infection in the mucosa was higher in men than women. In H. pylori-negative patients, TFF1 mRNA levels in women were significantly higher than in men, and TFF1 mRNA was significantly lower in positive than negative women. CONCLUSIONS: Sex differences in mucosal responses to H. pylori infection in the stomach may be correlated with sex differences in the incidence of stomach cancer.

Aged↗
PubMed2004

Diagnostic value of culture, histology and PCR for Helicobacter pylori in the remnant stomach after surgery.

BACKGROUND: Diagnosis of Helicobacter pylori infection in the remnant stomach has not been established. AIMS: To investigate the diagnostic value of culture, histology, PCR and serum IgG against H. pylori (ELISA) with and without eradication therapy in the remnant stomach, compared with the unoperated stomach. METHODS: Biopsy samples for bacterial culture and histological diagnosis of H. pylori were taken from the stoma and upper corpus of the remnant stomach and gastric juice was used for PCR assay. RESULTS: Bacterial culture-based diagnosis in the remnant stomach, sensitivity and specificity of culture were 95.1%, 100%; histology 89%, 92.3%; PCR 66%, 89.7%; and ELISA 100%, 50%, respectively, in cases without H. pylori eradication therapy. In assessment of the results of therapy for the remnant stomach, sensitivity and specificity of culture were 100%, 100%; histology 80%, 96.8%; PCR 80%, 91.7%; and ELISA 100%, 0%, respectively. CONCLUSION: Bacterial culture had the highest diagnostic value in the remnant stomach as well as unoperated stomach. Sensitivity by histology and PCR was lower in the remnant stomach than the unoperated stomach, but specificity values were equal. Serum ELISA assay was not suitable for the remnant stomach.

Adult↗