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S Yoshida

Publications and source records attributed to S Yoshida.

At least 55 records · Page 3Linked to original sources
PubMed2004

Narrow-band imaging in the diagnosis of colorectal mucosal lesions: a pilot study.

BACKGROUND AND STUDY AIMS: A newly developed narrow-band imaging (NBI) technique, in which modified optical filters were used in the light source of a video endoscope system, was applied during colonoscopy in a clinical setting. This pilot study evaluated the clinical feasibility of the NBI system for evaluating colorectal lesions. PATIENTS AND METHODS: A total of 43 colorectal lesions in 34 patients were included in the study. The quality of visualization of colorectal lesions and the accuracy of differentiation between neoplastic and non-neoplastic lesions using the NBI system were evaluated in comparison with results from conventional colonoscopy and with chromoendoscopy. RESULTS: For pit pattern delineation, NBI was superior to conventional endoscopy (P < 0.001), but inferior to chromoendoscopy (P < 0.05). NBI achieved better visualization of the mucosal vascular network and of the hue of lesions than conventional endoscopy (P < 0.05). However there was no significant difference between NBI and chromoendoscopy in differentiating neoplastic from non-neoplastic lesions (both techniques had a sensitivity of 100 % and a specificity 75 %). This was better than the results of conventional colonoscopy (sensitivity 83 %, specificity 44 %; P < 0.05 for specificity). CONCLUSIONS: These results suggest that in the examination of colonic lesions the NBI system provides imaging features additional to those of both conventional endoscopy and chromoendoscopy. For distinguishing neoplasms from non-neoplastic lesions, NBI was equivalent to chromoendoscopy.

Aged↗
PubMed2004

Imaging findings of urachal mucinous cystadenocarcinoma associated with pseudomyxoma peritonei.

Pseudomyxoma peritonei is an uncommon neoplastic condition in which gelatinous fluid-like materials are observed in the peritoneal cavity caused by the dissemination of mucinous adenocarcinoma. Although ruptured appendiceal mucocele is the most common cause, tumors arising from other organs may also cause pseudomyxoma peritonei. We report the imaging findings of an extremely rare case of urachal mucinous adenocarcinoma associated with pseudomyxoma peritonei on computed tomography and magnetic resonance imaging with histopathologic correlation.

Aged↗
PubMed2004

Rapid healing of intractable diabetic foot ulcers with exposed bones following a novel therapy of exposing bone marrow cells and then grafting epidermal sheets.

BACKGROUND: Diabetic foot ulcers with exposed bones commonly result in amputation. OBJECTIVES: To determine whether exposure of bone marrow cells and subsequent grafting of epidermal sheets accelerates healing and reduces the need for amputation. METHODS: Thirty-eight patients with chronic wounds caused by diabetes mellitus were enrolled in this study. Epidermal sheets obtained from suction blisters of each patient were grafted on to diabetic foot ulcers without exposed bones (n = 10) and were compared with the standard treatment of local wound care, debridement with a scalpel when indicated, bed rest and parenteral antibiotics (n = 8). In another group of patients, diabetic wounds with exposed bones were treated either with the standard procedure (n = 9) or with a newly developed experimental procedure (n = 11). In that new procedure, the affected bone was initially exposed by debridement with a scalpel, followed by partial excision with a bone scraper until fresh bleeding was observed from the exposed bone. The lesions were then immediately covered with an occlusive dressing, and finally the wound was covered with an epidermal graft of skin harvested from suction blisters. Patients in each group were matched with their counterparts by age, sex, wound size, wound infection and wound duration, to compare the time needed for total skin repair and rates of amputation. RESULTS: Epidermal grafting significantly accelerated the healing of diabetic foot ulcers (P = 0.042) without exposed bones, with site-specific differentiation. The newly developed combination therapy resulted in the healing of all diabetic ulcers with exposed bones without the occurrence of osteomyelitis or the necessity for amputation (P < 0.0001). CONCLUSIONS: Our study indicates that early aggressive debridement of diabetic foot ulcers with exposed bones down to a bleeding vascularized base and then grafting epidermal sheets significantly improves healing and reduces the rate of amputation.

Adult↗
PubMed2004

[A successful management of acute myocardial infarction with severe left main trunk lesion using beating heart coronary artery bypass grafting: report of a case].

A 56-year-old male was admitted for sudden onset of severe chest pain and diagnosed as acute myocardial infarction (AMI). Emergency coronary angiography revealed complete obstruction of the left anterior descending artery (LAD) and 99% stenosis of left circumflex coronary artery (LCX), which was almost same with obstruction of the left main trunk coronary artery. Emergency coronary artery bypass grafting (CABG) to LAD and LCX was performed under a beating-heart. Left ventricular wall motion was improved after bypass grafting. CABG under a beating-heart is a new strategy for critical cases such as acute coronary syndrome. The better patency rate and the more complete revascularization that may be achieved with the new generation of stabilizers and retractors may improve long-term results.

Coronary Angiography↗
PubMed2004

Effect of cis-diammine dichloroplatinum on vascular endothelial growth factor expression in uterine cervical carcinoma.

PURPOSE OF INVESTIGATION: In this study, we investigated the effects of cis-diammine dichloroplatinum (CDDP) on VEGF mRNA expression and VEGF production in uterine cervical carcinoma tissues obtained from patients with locally advanced disease and in CaSki cells cultured in vitro. METHODS: VEGF in cultured CaSki cells and in the culture media was measured using a sensitive enzyme-linked immunosorbent assay (ELISA) before and 24 h, 48 h and 72 h after 3 h exposure to CDDP. VEGF mRNA expression in CaSki cells was assessed by the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) before and 24 h and 48 h after 3 h exposure to CDDP. We also examined the effect of CDDP on microvessel counts in uterine cervical carcinoma tissues obtained before and after high-dose CDDP intraarterial chemotherapy. Immunohistochemical staining using a monoclonal antibody against CD34 was carried out with cervical carcinoma tissue specimens, and microvessel counts were quantified by counting vessels. RESULTS: CDDP treatment resulted in significant increases in not only VEGF concentrations in cultured CaSki cells and culture media but also in VEGF mRNA expression levels in cultured CaSki cells in a time-dependent and dose-dependent manner compared to untreated controls (p < 0.05, n = 5). On the other hand, VEGF concentrations and microvessel counts in cervical carcinoma tissues were significantly lower in cases with complete response (CR) and partial response (PR), compared to those before treatment (p < 0.05, n = 5 ). By contrast, in cases with no change (NC) to CDDP, both VEGF concentrations and microvessel counts did not decrease and rather showed a somewhat increase compared with levels prior to the treatment. CONCLUSIONS: These results suggest that CDDP-induced increases in VEGF production by cervical carcinoma cells may stimulate angiogenesis in the tumor lesion after CDDP treatment.

Antigens, CD34↗
PubMed2003

Methamphetamine differentially regulates hippocampal glucocorticoid and mineralocorticoid receptor mRNAs in Fischer and Lewis rats.

Fischer 344 (F344) and Lewis (LEW) rats differ in physiological regulation of the limbic-hypothalamo-pituitary-adrenal (LHPA) axis, such that F344 rats exhibit greater LHPA axis responses to a variety of stimuli. Furthermore, LHPA axis activity has been implicated in the development of sensitization to abused drugs, and F344 rats exhibit greater behavioral sensitization to psychostimulants. Accordingly, we hypothesized that there may be some overlap between the neurobiological mechanisms that underlie these strain differences in LHPA axis activity and in behavioral sensitization to psychostimulants. We examined the effects of acute and repeated methamphetamine (4 mg/kg) treatments on the regulation of hippocampal glucocorticoid receptors (GR mRNA) and mineralocorticoid receptors (MR mRNA) in F344 and LEW rats. Our results showed that acute treatment with methamphetamine (MAP) does not alter the level of expression of GR or MR mRNA in both strains. However, repeated treatments with MAP decreased the expression of hippocampal GR, but not MR mRNA specifically in F344 rats. The same repeated treatments had no effect on either GR or MR mRNA in LEW rats. This selective MAP regulation of the level of expression of hippocampal GR mRNA in F344 suggests that these receptors may play a role in the development of behavioral sensitization to MAP in this strain. The lack of alteration in hippocampal GR mRNA in LEW rats suggests that plasticity of hippocampal GR may not be critical for the development of behavioral sensitization to MAP in this strain.

Absorptiometry, Photon↗
PubMed2003

Effects of acetazolamide and 4-aminoprydine on the responses of deflationary slowly adapting pulmonary stretch receptors to CO2 inhalation in the rat.

The inhibitory effect of CO(2) on deflationary slowly adapting pulmonary stretch receptors (deflationary SARs) was investigated before and after administration of acetazolamide, a carbonic anhydrase (CA) inhibitor, or 4-aminopyridine (4-AP), a K(+) channel blocker, in anesthetized, artificially ventilated rats after unilateral vagotomy. CO(2) inhalation (maximum tracheal CO(2) concentration ranging from 9 to 12%) for approximately 60 s decreased the impulse activity of deflationary SARs but had no significant effect on tracheal pressure (P(T)) as an index of bronchomotor tone. Acetazolamide treatment (20 mg/kg) diminished the inhibitory response of deflationary SARs to CO(2) inhalation. 4-AP (0.7 and 2.0 mg/kg) dose-dependently attenuated the decrease in deflationary SAR activity induced by CO(2) inhalation. When comparing the maximum attenuation due to 4-AP (2.0 mg/kg) and acetazolamide (20 mg/kg) in CO(2)-induced deflationary SAR inhibition, blockade of K(+) channels had a more pronounced effect. These results suggest that inhibition of deflationary SARs by CO(2) inhalation may be largely mediated by the stimulating action of 4-AP-sensitive K(+) currents in the nerve terminals of the receptors.

4-Aminopyridine↗
PubMed2003

Add-on effects of suplatast tosilate in bronchial asthma patients treated with inhaled corticosteroids.

Th2 cytokines play an important role in the pathogenesis of asthma. In the present study, we investigated the effect of suplatast tosilate, a selective Th2 cytokine inhibitor, on asthma control, in terms of subjective symptoms and pulmonary function in patients treated with inhaled corticosteroids. Thirty-eight patients with bronchial asthma being treated with inhaled corticosteroids were given suplatast tosilate (100 mg three times daily) for 12 weeks, in a multicenter setting. During the study period, other medications were continued. Morning and evening peak expiratory flow, asthma symptoms, blood eosinophil count and serum IgE levels were monitored. Suplatast tosilate treatment was associated with a significant improvement in mean morning peak expiratory flow (from 295 L/min to 348 L/min, P < 0.01) and evening peak expiratory flow (from 313 L/min to 357 L/min, P < 0.01). The mean daily variation in peak expiratory flow was significantly reduced (from 11.6% to 7.3%, P < 0.01) by suplatast tosilate treatment. The greatest improvement in peak expiratory flow was observed in patients whose blood eosinophil counts were decreased by suplatast tosilate treatment. Treatment with suplatast tosilate improved pulmonary function in patients with bronchial asthma. Our results suggest the therapeutic effects observed may occur through suppression of eosinophilic inflammation.

Administration, Inhalation↗
PubMed2003

Evaluation of mutans streptococci in plaque and saliva: correlation with caries development in preschool children.

OBJECTIVES: To test the ability of a site-specific method of evaluating mutans streptococci (MS) present in plaque in order to predict caries risk in children and to compare the results with those obtained from estimating the levels of MS present in saliva. METHODS: Caries prevalence was examined twice, 6 months apart, in 129 preschool children ranging in age from 1.5 to 5. A commercial strip method was used to evaluate the MS score (0-3) in plaque collected from four selected tooth surfaces at two interdental spaces and in saliva. RESULTS: The screening criteria of the MS score for caries incidence between scores 1 and 2, and scores 0 and 1 were the most valid for evaluating plaque (accuracy of prediction, 80%) and saliva (accuracy of prediction, 71%), respectively. Based on these screening criteria, the evaluation of saliva MS was invalid when the plaque MS score was considered. Screening plaque MS was effective, regardless of caries experience at baseline, according to the chi-square test (p<0.01), but screening saliva MS was ineffective when caries experience was present at baseline. A multivariate logistic regression analysis including six variables showed that the plaque MS score and caries experience at baseline were significantly correlated with caries incidence: caries experience at baseline (OR=5.02, 95%CI: 1.81-14.59) and high plaque MS score (2 or 3) (OR=12.59, 95%CI: 3.18-67.08). CONCLUSIONS: These results suggest that the semi-quantitative evaluation of plaque MS sampled from only two proximal sites on the molars is more effective for screening preschool children at a high risk of developing caries in their primary dentition than other important caries risk indicators.

Chi-Square Distribution↗
PubMed2003

A mouse model of the atopic eczema/dermatitis syndrome by repeated application of a crude extract of house-dust mite Dermatophagoides farinae.

BACKGROUND: We cultured Dermatophagoides farinae (Df), one of the most common mites in house dust and the most important allergen among natural allergens. With this material, we attempted to produce an animal model of the atopic eczema/dermatitis syndrome (AEDS). METHODS: We cultured Df mites in high density and prepared a crude extract of Df (DfE) together with the culture medium. We applied the extract to the back skin of NC/Nga and BALB/c mice three times per week for 8 weeks. RESULTS: In the NC/Nga group, dryness or scaling appeared on the skin, and scratching behavior increased at the second week in the DfE-treated group. Skin erosion and hemorrhage occurred at the fourth week. The epidermis thickened and deepened into the upper dermis, in which mast cells were highly accumulated, corresponding with the skin lesion of AEDS patients. Specific IgE and IgG to DfE and total IgE were elevated in the sera. Mice treated with an extract of mite culture medium did not develop skin lesions. In the BALB/c group, mice developed specific IgE and IgG to DfE, however, no typical skin lesions appeared. Mast cells in the upper dermis did not increase. CONCLUSIONS: Repeated painting of Dermatophagoides extract produced IgE-associated AEDS-like lesions on the skin of NC mice.

Allergens↗
PubMed2003

The percentage of myeloperoxidase-positive blast cells is a strong independent prognostic factor in acute myeloid leukemia, even in the patients with normal karyotype.

To examine whether the percentage of myeloperoxidase (MPO)-positive blast cells is useful as a prognostic factor for acute myeloid leukemia (AML), cytochemical analysis of MPO was performed in 491 patients who were registered to the Japan Adult Leukemia Study Group-AML92 study. Patients were divided into two using the percentage of MPO-positive blast (high [>or=50%] and low (<50%)). Complete remission rates were 85.4% in the former and 64.1% in the latter (P=0.001). The overall survival (OS) and the disease-free survival (DFS) were significantly better in the high MPO group (48.3 vs 18.7% for OS, and 36.3 vs 20.1% for DFS, P<0.001, respectively). Multivariate analysis showed that both karyotype and the percentage of MPO-positive blast cells were equally important prognostic factors. The high MPO group still showed a better survival even when restricted to the intermediate chromosomal risk group or the patients with normal karyotype (P<0.001). The OS of patients with normal karyotype in the high MPO group was almost equal with that of the favorable chromosomal risk group. The percentage of MPO-positive blast cells is a simple and highly significant prognostic factor for AML patients, and especially useful to stratify patients with normal karyotype.

Acute Disease↗
PubMed2003

Prolonged recovery of ultraviolet B-irradiated skin in neuropsin (KLK8)-deficient mice.

BACKGROUND: Neuropsin (KLK8), a serine protease of the kallikrein family, is thought to be involved in the function of keratinocytes, i.e. migration, differentiation and desquamation. However, how neuropsin participates is still unknown. OBJECTIVE: To observe the epidermal function of serine protease in neuropsin-deficient mice. METHODS: We irradiated the skin of neuropsin-deficient mice with ultraviolet light to induce acute inflammation and compared the morphology with that of wild-type mice. RESULTS: We observed a phenotypic change in the epidermis. An acute inflammatory dose of ultraviolet light induced a marked increase in neuropsin mRNA expression in the skin. The signal intensity of the mRNA expression was highest on day 2-3 after irradiation, when keratinocytes were aligned irregularly in the recovery period. Morphological comparison between neuropsin -/- and +/+ mice revealed that an irregular alignment of cells in the thickened epidermis was obvious on day 2 after irradiation in the wild-type mice, whereas it was prolonged for at least 2 days in the neuropsin-deficient mice. The stratum corneum of neuropsin-deficient mice was remarkably thicker than that of the wild-type mice at 5, 14 and 21 days after irradiation. The increase, as a response to this stimulus, in involucrin immunoreactivity, a marker for cell envelope assembly, was delayed in the mutant mice. CONCLUSIONS: Thus, neuropsin might be involved early in the process of differentiation, such as in the assembly of the cell envelope, but not in migration and desquamation.

Acute Disease↗
PubMed2003

Functional magnetic resonance imaging of human jaw movements.

This study used functional magnetic resonance images (fMRI) to examine brain activity during clenching, gum chewing, and tapping tasks. It has been considered difficult to obtain sufficient fMRI data during jaw movement because the head motion associated with the jaw movements creates artifacts on the images. To avoid these artifacts, larger pixels were used, thus allowing some head motion of the subjects, and data from subjects where the heads were evaluated to have moved more than 0.5 mm were discarded. Further, all pixels obtained by fMRI were evaluated and pixels positively synchronized with the task, which were considered to show brain activity, were selected. Sufficient fMRI data was obtained from 30 experiments, 10 sets for each task. During the clenching and tapping tasks, the activated pixels were in the sensory, motor and pre-motor cortexes, and in the sensory and motor cortexes but not in the pre-motor cortex during the gum chewing task. There appears to be no significant differences between right- and left-hemispheres. It is conceivable that there are differences between voluntary jaw movements (clenching and tapping tasks) and mastication (gum chewing task) concerning the control of jaw movements.

Brain↗
PubMed2003

Effects of estriol on cell viability and 1,25-dihydroxyvitamin D3 receptor mRNA expression in cultured human osteoblast-like cells.

It is clinically evident that administration of estriol (E3) increases the bone mass density of the lumbar vertebrae in postmenopausal women, and that combined treatment with estrogen and 1,25-dihydroxyvitamin D3 (VD3) increases femoral neck bone mass density compared with treatment with estrogen alone in postmenopausal osteoporotic women. However, the molecular mechanism whereby treatment with E3 affects osteoblast cell function is still unknown. This study was conducted first to examine the comparative effects of E3 and VD3 on the cell viability of cultured human osteoblast-like cells (HOS) and second to determine whether E3 affects VD3 receptor mRNA expression in HOS. The cell viability and VD3 receptor mRNA expression of cultured HOS were assessed by MTT assay and semi-quantitative reverse transcriptase-polymerase chain reaction with Southern blot analysis, respectively. The treatment with E3 increased the cell viability of cultured HOS compared with untreated control cultures. The increase in cell viability caused by the treatment with E3 was further augmented by the combined treatment with VD3. The addition of either E3 (3.52 x 10(-8) mol/l) or E3 (3.52 x 10(-7) mol/l) to cultured HOS for 24 h resulted in a fourfold and eightfold increase, respectively, in VD3 receptor mRNA expression in HOS, compared with that in untreated control cultures. These results suggest that E3 may up-regulate the cell viability of osteoblast cells, and that the concomitant treatment with E3 and VD3 further augments the cell viability being associated with an E3-induced increase in VD3 receptor mRNA expression in those cells.

Calcitriol↗