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H Yoshida

Publications and source records attributed to H Yoshida.

At least 19 recordsLinked to original sources
PubMed2007

Association of vascular parkinsonism with impaired neuronal integrity in the striatum.

The purpose of this study is to identify the underlying differences between patients with white matter lesions (WMLs) who manifested gait disturbance suggestive of vascular parkinsonism (VaP) and those who did not, using the PET scan. Fourteen patients with extensive WMLs, as determined by MRI, were divided into two groups - 7 with gait disturbance and 7 without it. Neuronal integrity was evaluated with a PET scan using [(11)C]flumazenil (FMZ) by calculating the distribution volume of FMZ (FMZ-V(d)) in various regions of interest by non-linear curve fitting. Additionally, tracer kinetic analysis was applied for voxel-by-voxel quantification of FMZ-V(d) and data analysis was performed using statistical parametric mapping. The striatal FMZ-V(d) values were inversely correlated with the motor UPDRS scores (r = 0.70, p < 0.005), and their reductions were associated with the presence of gait disturbance. Therefore, differences in neuronal integrity in the striatum may determine whether patients with WMLs develop VaP or not.

Aged↗
PubMed2007

Bicalutamide 80 mg combined with a luteinizing hormone-releasing hormone agonist (LHRH-A) versus LHRH-A monotherapy in advanced prostate cancer: findings from a phase III randomized, double-blind, multicenter trial in Japanese patients.

To compare combination therapy with bicalutamide 80 mg and a luteinizing hormone-releasing hormone agonist (LHRH-A) versus LHRH-A alone in Japanese men with untreated advanced prostate cancer. A total of 205 patients with stage C/D prostate cancer were randomized to either LHRH-A+once-daily oral bicalutamide 80 mg or placebo. Primary study variables have been reported previously. Secondary variables included: time to achieve prostate-specific antigen < or = 4 ng/ml, time-to-treatment failure (TTTF), time-to-disease progression (TTP), overall survival (OS), adverse events and adverse drug reactions. Following combination therapy with bicalutamide 80 mg, there were significant (P<0.001) advantages over LHRH-A alone in terms of TTTF and TTP, but the difference in the interim OS was not statistically significant. First-line combination therapy with bicalutamide 80 mg in Japanese patients with advanced prostate cancer offers significant benefits over LHRH-A alone, with respect to TTTF and TTP. Follow-up for OS continues.

Aged↗
PubMed2006

Absence of tyrosine kinase mutations in Japanese colorectal cancer patients.

Tyrosine kinases, which are important regulators of intracellular signal-transduction pathways, have mutated forms that are often associated with oncogenesis and are attractive targets for therapeutic intervention. Recently, systematic mutational analyses of tyrosine kinases revealed that a minimum of 30% of colorectal cancer contain at least one mutation in the tyrosine kinases. To further explore these mutations, we examined all reported mutations of NTRK3, FES, KDR, EPHA3, NTRK2, JAK1, PDGFRA, EPHA7, EPHA8, ERBB4, FGFR1, MLK4 and GUCY2F genes in the 24 colorectal cancer cell lines. Unexpectedly, among 24 colorectal cancer cell lines, only two cell lines (LoVo and CaR1) harbored mutation C1408T (R470C) in MLK4 gene. The mutation rate was extremely low compared to that previously reported. Therefore, we analyzed mutations in 46 colorectal cancer samples resected from the same number of Japanese patients. Surprisingly, none of the 46 samples contained any of the mutations reported. Based on our study, we advise that a more comprehensive tyrosine kinase gene mutation assay is necessary in the future.

Aged↗
PubMed2006

Gastric cancer among peptic ulcer patients: retrospective, long-term follow-up.

BACKGROUND: Patients with duodenal ulcer are not at high risk although Helicobacter pylori infection is no doubt associated with gastric cancer development. However, little is known about the risk after long-term follow-up. AIMS: We investigated the incidence for gastric cancer development in peptic ulcer patients in a long term. PATIENTS AND METHODS: Between 1965 and 2004, endoscopic follow-up of more than 1 year was conducted on 1504 peptic ulcer patients in our hospital. They consisted of 978 gastric ulcer patients, 444 duodenal ulcer patients and 82 gastric and duodenal ulcer patients. Gastric and duodenal ulcer patients were excluded from the analysis because of their limited number. RESULTS: Gastric cancers developed in 32 (3.3%) of gastric ulcer patients and 3 (0.68%) of duodenal ulcer patients. Kaplan-Meier analysis showed that the incidence of gastric cancer in duodenal ulcer patients was significantly lower than that in gastric ulcer patients (log-rank test, p=0.0059). Cox's proportional hazard model denoted the relative risk for duodenal ulcer against gastric ulcer adjusted by sex and age as 0.23 (95% CI: 0.072-0.77, p=0.016). CONCLUSION: The risk for patients with duodenal ulcer to develop gastric cancer over the long term is significantly less than in those with gastric ulcer.

Duodenal Ulcer↗
PubMed2006

Submandibular abscess caused by Salmonella.

Salmonella species represent uncommon causative agents in focal infections of the head and neck. This article presents a rare case of Salmonella submandibular abscess in a 59-year-old patient with diabetes mellitus, chronic hepatitis and liver cirrhosis. The patient was successfully treated with drainage of the abscess and oral administration of quinolone. An immunocompromised condition can be a critical predisposing factor for Salmonella submandibular abscess.

Abscess↗
PubMed2006

Pilot evaluation of selective serotonin reuptake inhibitor antidepressants in hot flash patients under androgen-deprivation therapy for prostate cancer.

PURPOSE: Hot flash (HF) is a common side effect in prostate cancer patient undergoing androgen-deprivation therapy (ADT). In this study, we evaluated the efficacy of paroxetine (selective serotonin reuptake inhibitors (SSRIs)) for HF. PATIENTS AND METHODS: In total, 10 men with prostate cancer under ADH who were suffering with HF entered this study. Self-report questionnaire was used for the evaluation. RESULTS: The average rating for HF frequency decreased (P=0.009) and HF severity decreased (P=0.0332) also, reported QOL score increased (P=0.0218). CONCLUSION: These preliminary data suggest that low dose (10 mg/day) of antidepressant paroxetine can be helpful in the treatment of HFs in patients under ADT for prostate cancer. Further controlled studies are needed to more fully evaluate the efficacy of the SSRIs.

Aged↗
PubMed2006

Development of PCR-based allele-specific and InDel marker sets for nine rice blast resistance genes.

Blast resistance is one of the most important traits in rice breeding, and application of molecular markers for blast resistance breeding is likely to allow the rapid screening for the trait during early growth stages, without the need for inoculation of pathogen and phenotyping. Allele-specific PCR markers and insertion/deletion (InDel) markers, which genotype single-nucleotide polymorphisms and InDel polymorphisms, respectively, are useful tools for marker-assisted selections. We developed sets of allele-specific PCR and InDel markers for nine rice blast resistance genes -- Piz, Piz-t, Pit, Pik, Pik-m, Pik-p, Pita, Pita-2, and Pib -- which are commonly used in Japanese blast resistance rice breeding programs. For each resistance gene, we used the segregation information from thousands of progeny in several crosses or published gene locations to generate a marker that cosegregated with the gene and markers that closely flanked the gene on either side. The developed cosegregating markers uniquely discriminated among each of the lines with the individual resistance genes (except for Pita and Pita-2). Therefore, these markers will likely facilitate the development of multiline cultivars carrying one or a combination of these nine blast resistance genes. In addition, the systems we developed may be valuable tools in the quality control of seed production from blast-resistant multiline cultivars.

Alleles↗
PubMed2006

Ischemia-induced disturbance of neuronal network function in the rat spinal cord analyzed by voltage-imaging.

Using a voltage-imaging technique, we analyzed the acute effect of ischemia, hypoxia and hypoglycemia on the neuronal network function of the rat spinal cord. Ischemic, hypoxic, or hypoglycemic stress was loaded to spinal cord slices with an oxygen- and glucose-free, oxygen-free, or glucose-free mock cerebrospinal fluid, respectively. Depolarizing signals in the dorsal horn, induced by dorsal root stimulation, consisted of fast (pre-synaptic) and slow (post-synaptic) components. The slow component was attenuated much more than the fast component under an ischemic condition (P<0.0002). Post-synaptic neuronal activities in lamina III-IV were suppressed earlier than those in lamina I-II. The nerve fiber was relatively resistant to ischemia. As long as the fast component was preserved in the dorsal horn, the suppression of the fast and slow components was reversible. There was a significant difference (P<0.05) in the recovered slow component sizes between the group in which the fast component was suppressed by more than 20% by ischemia and the group in which the suppression was less than 20%. Further prolonged stress irreversibly eliminated most of the slow component, and attenuated the fast component (to 59+/-8%) accompanied by cellular damage in histology. Suppression of neural activity by hypoxic or hypoglycemic stress was less prominent than that by ischemia. Prolonged ischemic stress suddenly and irreversibly eliminated depolarizing signals in the ventral horn accompanied by morphological damage of motoneurons. Immunohistochemical staining was negative for apoptosis. We have, for the first time, analyzed the processes of spinal cord disturbance induced by ischemia, hypoxia and hypoglycemia at the neuronal network level by directly observing the regional neuronal network activities within the spinal cord. We conclude that synaptic transmission in the dorsal horn, especially in deep regions, is vulnerable and first affected by these stresses. Severe ischemic stress induces irreversible dysfunction of neurons accompanied by eventual cell death in both dorsal and ventral horns.

Animals↗
PubMed2006

Terahertz surface-wave resonant sensor with a metal hole array.

A surface-wave sensor based on the resonant transmission characteristics of metal hole arrays is demonstrated in the terahertz (THz) region. Since the frequency of the transmission peak of a metal hole array, which corresponds to the resonant frequency of the surface waves, is particularly sensitive to the refractive index in the vicinity of the metal surface, a very small change in the substances attached to the surface can be detected by monitoring the transmission spectrum. By attaching a layer of substance (thickness t < 5 microm) much thinner than the wavelength of the THz wave (lambda(THz) = 1 mm at 0.3 THz) to the surface of a metal hole array, we demonstrated that the existence of such a small amount of substance can be detected more easily than without the metal hole array. This demonstration of THz sensing with metal hole arrays indicates the possibility of realizing THz surface-wave sensors for biochemical molecules in the THz region.

Journal Article↗
PubMed2006

Artificial ascites technique for percutaneous radiofrequency ablation of liver cancer adjacent to the gastrointestinal tract.

BACKGROUND: Percutaneous radiofrequency ablation (RFA) of liver tumours adjacent to the gastrointestinal tract is controversial. This study assessed the value of an intraperitoneal water infusion (artificial ascites) technique for percutaneous RFA of such tumours. METHODS: Before ablation in 52 patients (55 treatments, 58 tumours), between 250 and 3000 (mean 681) ml 5 per cent glucose solution was infused into the abdominal cavity using a 14-G needle, with the aim of preventing thermal injury by separating the liver from the gastrointestinal tract. RESULTS: There were no adverse events associated with the artificial ascites technique. In 43 (78 per cent) of the 55 treatments, the liver and gastrointestinal tract were separated successfully. In the other 12 treatments, in which the separation was not confirmed by real-time ultrasonography, there was one case of perforation of the ascending colon after RFA; adhesion of the liver and colon resulting from previous laparotomy may have been related to the injury. CONCLUSION: Production of artificial ascites can be undertaken safely, making RFA safe and effective for hepatic tumours adjacent to the gastrointestinal tract. In patients with possible postoperative adhesions, confirmation of separation of the liver from surrounding organs is mandatory to avoid thermal injury.

Aged↗
PubMed2006

CagA protein secreted by the intact type IV secretion system leads to gastric epithelial inflammation in the Mongolian gerbil model.

Helicobacter pylori causes various gastro-duodenal diseases, including gastric cancer. The CagA protein, an H. pylori virulence factor, induces morphological changes in host cells and may be associated with the development of peptic ulcer and gastric carcinoma. The present study has analysed the role of CagA protein in the pathogenesis of H. pylori infection in the Mongolian gerbil model. Mongolian gerbils were challenged with wild-type H. pylori strain TN2, which has a functional cag pathogenicity island or isogenic mutants with disrupted cagA (DeltacagA) or cagE (DeltacagE) genes. They were sacrificed at 7, 13, and 25 weeks after inoculation. Pathological changes of the gastric mucosa were determined and apoptosis was assessed by the TUNEL assay. Immunohistochemistry for PCNA, phospho-IkappaBalpha, and phospho-Erk was also performed. All of the bacterial strains colonized the gerbil stomach at similar densities; however, the DeltacagA mutant induced milder gastritis than did the wild type. The extent of apoptosis and lymphoid follicle formation in the epithelium appeared to depend on intact cagA. The DeltacagA mutant induced less phosphorylation of IkappaBalpha and Erk, and less expression of interferon-gamma and interleukin-1beta mRNA in the epithelium than did the wild type. It is concluded that CagA protein may be essential for the induction of severe gastritis in the Mongolian gerbil model.

Animals↗
PubMed2006

A prospective study to evaluate a new dental management protocol before hematopoietic stem cell transplantation.

Pre-hematopoietic stem cell transplantation (HSCT) dental treatment is essential to prevent serious infections from oral sources during immunosuppression, in patients who undergo HSCT therapy. This study was planned to establish a dental management protocol for such patients. Forty-one patients scheduled for HSCT to treat hematological malignancies were consecutively enrolled in the prospective trial. The dental status of all patients was evaluated by clinical and radiographic examination at a median of 47 days before the commencement of HSCT therapy. Thirty-six patients had one or more dental diseases; the remaining five had none. Caries was found in 26 patients, apical periodontitis in 19, marginal periodontitis in 24 and a partially erupted third molar in 11. Our policy is to preserve patients' teeth whenever possible, and therefore minimal dental intervention was planned. Treatment was completed for all 36 patients with dental pathologies, before the conditioning regimen began. All patients received the scheduled HSCT therapy without alteration, interruption or delay, and did not show any signs or symptoms associated with odontogenic infection while they were immunosuppressed. This protocol, therefore, appears to be appropriate for the pre-HSCT dental treatment of patients with hematological diseases.

Adolescent↗
PubMed2006

Methionine-rich storage protein gene in the rice stem borer, Chilo suppressalis, is expressed during diapause in response to cold acclimation.

Gene expressions of acclimatized and non-acclimatized diapausing larvae were examined in Chilo suppressalis using a subtraction technique. A gene encoding a methionine-rich storage protein, CsSP1, was cloned and its complete cDNA sequence was determined. Potentially, CsSP1 encoded a 758-amino acid protein, with a calculated molecular weight of 88.8 kDa. The expression level of CsSP1 was higher in nondiapausing larvae than in diapausing ones. The CsSP1 expression was up-regulated in diapausing larvae when the temperature of cold acclimation was shifted to 5 degrees C. The up-regulated level was maintained at 40 days after incubation at 5 degrees C. In nondiapausing larvae, CsSP1 expression was down-regulated when the temperature was below developmental zero. Involvement of CsSP1 in diapause, cold tolerance acquisition and postdiapause development in C. suppressalis is discussed.

Acclimatization↗
PubMed2006

Prediction of femoral head collapse in osteonecrosis.

The femoral head deteriorates in osteonecrosis. As a consequence of that, the cortical shell of the femoral head can buckle into the cancellous bone supporting it. In order to examine the buckling scenario we performed numerical analysis of a realistic femoral head model. The analysis included a solution of the hip contact problem, which provided the contact pressure distribution, and subsequent buckling simulation based on the given contact pressure. The contact problem was solved iteratively by approximating the cartilage by a discrete set of unilateral linear springs. The buckling calculations were based on a finite element mesh with brick elements for the cancellous bone and shell elements for the cortical shell. Results of 144 simulations for a variety of geometrical, material, and loading parameters strengthen the buckling scenario. They, particularly, show that the normal cancellous bone serves as a strong supporting foundation for the cortical shell and prevents it from buckling. However, under the development of osteonecrosis the deteriorating cancellous bone is unable to prevent the cortical shell from buckling and the critical pressure decreases with the decreasing Young modulus of the cancellous bone. The local buckling of the cortical shell seems to be the driving force of the progressive fracturing of the femoral head leading to its entire collapse. The buckling analysis provides an additional criterion of the femoral head collapse, the critical contact pressure. The buckling scenario also suggests a new argument in speculating on the femoral head reinforcement. If the entire collapse of the femoral head starts with the buckling of the cortical shell then it is reasonable to place the reinforcement as close to the cortical shell as possible.

Computer Simulation↗
PubMed2006

Renal adenocarcinoma in a ferret.

A spontaneous case of renal tumor was observed in a 7-year-old ovariectomized female pet ferret (Mustela putorius furo). Clinical signs included exhaustion, emaciation, anorexia, and stooping position. At necropsy, a solid and cystic mass replaced the left kidney and adrenal gland. The tumor was composed of pleomorphic epithelial cells with a large number of giant cells. Metastases were recognized in the lung, liver, greater omentum, right renal pelvis, and systemic lymph nodes. Immunohistochemical stains revealed that the tumor cells were positive for CD10, cytokeratin (CAM 5.2), and Ki-67 (MIB-1). On the basis of morphologic and immunohistochemical features, the tumor was diagnosed as a pleomorphic renal adenocarcinoma. This type of neoplasm is very rare in all species and has never been reported in a ferret.

Adenocarcinoma↗
PubMed2006

Cytoplasmic antineutrophil cytoplasmic antibody positive pauci-immune glomerulonephritis associated with infectious endocarditis.

Renal deterioration often occurs in cases of infectious endocarditis (IE), but, IE- associated nephritis with rapidly progressive glomerulonephritis (RPGN) is rare. Patients with severe infection (e.g., IE) sometimes show positivity for cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA). Therefore, diagnosis and treatment are very difficult in cases of RPGN with IE and positivity for C-ANCA. Such cases are rare, only 12 have been reported in the English literature. Herein, we describe the case of a 50-year-old man who presented with RPGN with IE and tested positively for C-ANCA. He was referred to our hospital because of leg edema, purpura and renal dysfunction. Laboratory tests revealed serum creatinine elevation and positivity for C-ANCA and proteinase 3-specific (PR3)-ANCA. RPGN and acute renal failure were diagnosed. Hemodialysis and steroid therapy were started. Streptococcus oralis was isolated by blood culture. Transthoracic echocardiography revealed grade III mitral valve insufficiency with two vegetations. Therefore, IE was diagnosed. The steroid therapy was stopped, and antibiotic therapy was begun. Because there was no improvement, surgical therapy was performed. The operation was successful, but the patient died of brain hemorrhage. Our experience in this case indicates C/PR3-ANCA positive RPGN must be ruled out in patients with infectious disease, particularly IE, together with renal symptoms, and renal biopsy should be performed.

Acute Kidney Injury↗
PubMed2006

[Infectious tricuspid valve endocarditis in a chronic hemodialysis patient; report of a case].

We report a rare case of isolated infectious tricuspid valve endocarditis. A 67-year-old male patient with chronic renal failure complained of fever up to 38 degrees C after hemodialysis. WBC was not elevated, but CRP was increased. Transthoracic and transesophageal echocardiography for investigating his chest discomfort demonstrated a large 13 x 25 mm vegetation on the tricuspid valve. Blood culture was negative. The tricuspid valve was replaced with a bioprosthetic valve. The extensive vegetation was found in the anterior, septal and posterior cusps and diagnosed as infectious endocarditis pathologically. The postoperative course was uneventful. WBC and CRP remained normal 9 months after surgery and no signs of recurrence were observed. The cause of the infectious endocarditis seemed to be the insertion of a double lumen catheter for dialysis or the puncture of the arteriovenous shunt.

Aged↗