Biomedical subjects

S Takata

Publications and source records attributed to S Takata.

At least 19 recordsLinked to original sources

PubMed2005

Morphological changes in human gastric tumours after eradication therapy of Helicobacter pylori in a short-term follow-up.

BACKGROUND: It is controversial as to whether the development of gastric cancer is influenced by Helicobacter pylori eradication. If eradication itself influences the tumour morphology, this may affect the tumour discovery rate. AIM: To investigate the morphological changes in the gastric neoplasm after H. pylori eradication. METHODS: We studied 37 patients with eradication therapy. After a 1-month follow-up, endoscopic re-evaluation was performed and the appearance was compared with first image. All lesions were resected endoscopically, and were subjected to histological assessment and to immunohistochemistry. Serum gastrin levels were determined before and after eradication. RESULTS: Twenty-nine of 37 patients underwent successful eradication. The appearance of 11 lesions (33% of 33 lesions) became indistinct after successful eradication. All lesions were of the superficial-elevated type and the height of the lesions decreased. We detected normal columnar epithelium over the neoplasm in eight of the lesions. Higher expression of single-stranded deoxyribonucleic acid in the deep area was characteristic in tumours with an indistinct appearance. These changes did not correlate with the serum gastrin levels. CONCLUSIONS: The morphology of the gastric neoplasm change after eradication in the short-term. This may contribute to the decreased tumour discovery rate.

Adenocarcinoma↗

PubMed2004

Barium sulphate with a negative zeta potential accelerates skin permeability barrier recovery and prevents epidermal hyperplasia induced by barrier disruption.

BACKGROUND: Barium sulphate, a stable inorganic material, has been used in contrast media and cosmetic products because of its stability. As a negative external electric potential accelerates the skin barrier repair after barrier disruption, we hypothesized that topical application of barium sulphate may affect the skin barrier recovery rate depending on its zeta potential. OBJECTIVES: To investigate whether barium sulphate particles in aqueous solution have different zeta potentials depending on their surface structure, and to investigate the possible relation between zeta potential and skin barrier recovery rate. METHODS: Mice were subjected to tape stripping to disrupt barrier function, or were treated with acetone and kept in a dry environment to induce epidermal hyperplasia. They were then treated with different forms of barium sulphate, and barrier recovery was monitored by measurements of transepidermal water loss. RESULTS: There was a significant correlation between the barrier recovery rate and zeta potential of barium sulphate applied topically. Barium sulphate with a negative zeta potential significantly accelerated barrier recovery, but barium sulphate with a positive zeta potential did not accelerate or even delayed barrier repair. Barium sulphate with a negative zeta potential had an X-ray diffraction pattern different from that with a positive potential. The distribution of calcium in the epidermis was also influenced by the polarity of zeta potential. CONCLUSIONS: These findings suggest a new pharmacological approach towards altering barrier function or epidermal hyperplasia with inorganic particles in healthy and diseased skin.

Administration, Cutaneous↗

PubMed2003

Decreased computed tomographic lung density during exacerbation of asthma.

Recently, it was shown that both mean lung density (MLD) and the relative lung area with an attenuation of <-950 HU (RA950) are related to severity of asthma in nonsmoking asthmatics. The aim of the present study was to examine whether reduced computed tomography (CT) lung density during exacerbation could change after treatment. A cross-sectional study was performed to compare CT lung density in 30 stable asthmatics, 30 unstable asthmatics and 25 control subjects. In order to investigate longitudinally the effect of treatment on decreased CT lung density, 17 asthmatics with an exacerbation were followed at the initiation of treatment and 2 months after relief. The MLD was significantly lower and the RA950 significantly higher in unstable asthmatics than in controls and stable asthmatics. Both MLD and RA950 changed significantly with administration of systemic glucocorticoid therapy. The changes in forced expiratory volume in one second correlated significantly with those in both MLD and RA950. The changes in residual volume also correlated significantly with those in both MLD and RA950. It was concluded that decreased computed tomographic lung density during an asthma exacerbation is at least partially reversible, and changes in mean lung density and the relative lung area with a radiation attenuation of <-950 HU are related to the change in forced expiratory volume in one second and residual volume.

Adult↗

PubMed2002

Cyclic thrombocytopenia and polycythemia vera.

A periodic fall of platelet number characterizes an acquired pathological condition named cyclic thrombocytopenia. We describe an unusual case of polycythemia vera in which the episodes of thrombocytopenia were followed regularly by thrombocytosis. The period of platelet count fluctuation was about 50 days, with the counts ranging from 34 to 820 x 10(9)/l. Bone marrow megakaryocytes were decreased in number during platelet nadir. Circulating thrombopoietin levels fluctuated out of phase with the platelet count. We suggest that at least some cases of polycythemia vera may have an unstable hematopoietic stem cell pool in nature, which could contribute to the development of unprovoked cyclic thrombocytopenia.

Aged↗

PubMed2002

Fournier's gangrene after unrelated cord blood stem cell transplantation.

A 16-year-old boy with refractory acute myelogenous leukemia developed Fournier's gangrene as an early complication after two-antigen HLA-mismatched unrelated cord blood stem cell transplantation. On day 25 after the transplantation, he noted abrupt onset of penile swelling with miction pain. The penile inflammation rapidly extended posteriorly to involve the scrotum and perianal tissues, inferiorly to involve the thighs, and superiorly up the lower abdominal region within the next 36 h, and he died from sepsis on day 27. Fournier's gangrene presenting as a genitoperineal necrotizing fasciitis should be considered as a potential complication in umbilical-cord blood recipients in the cytopenic post-transplant phase.

Adolescent↗

PubMed2002

Bilateral adrenal hemorrhage in essential thrombocythemia.

A 67-year-old woman with previously untreated essential thrombocythemia developed bilateral adrenal hemorrhage. She had no known vascular risk factors including smoking, diabetes mellitus, hypertension, and hypercholesterolemia. Her platelet count was 921 x 10(9)/l. She received preemptive steroid therapy to prevent the occurrence of adrenal crisis, but 5 weeks later the replacement therapy was discontinued because the patient fully recovered with a normal adrenocorticotropic hormone stimulation test. Thereafter, she remained well for more than 4 years with a platelet count ranging from 600 to 800 x 10(9)/l. Although adrenal hemorrhage is very rare, it can occur as a hemorrhagic complication of essential thrombocythemia.

Adrenal Gland Diseases↗

PubMed2001

Percutaneous transluminal mitral valvuloplasty improves cardiopulmonary baroreflex sensitivity in patients with mitral stenosis.

Patients with heart failure frequently have increased sympathetic tone, which could result in part from impairment of the inhibitory influence of cardiopulmonary baroreflexes. Percutaneous transluminal mitral valvuloplasty (PTMV) provides a unique model for evaluating functional changes in cardiopulmonary baroreflexes without open-heart surgical manipulation. We examined the effects of PTMV on cardiopulmonary baroreflexes and sympathetic nerve activity in 10 patients with mitral stenosis. We measured muscle sympathetic nerve activity using microneurography. Cardiopulmonary baroreflex provocation was performed by applying a lower body negative pressure of -10 mm Hg, and its sensitivity was determined by dividing the percent change in muscle sympathetic nerve activity by the change in central venous pressure. Response to isometric exercise was assessed by handgrip at 30% of maximal voluntary contraction for 3 min. PTMV significantly increased mitral valve area and cardiac index and decreased mean left atrial pressure. PTMV significantly decreased burst rate from 25.1+/-2.5 to 15.6+/-2.6 bursts/min (p < 0.01) and burst incidence from 37.1+/-3.7 to 23.6+/-3.3 bursts/100 heart beats (p < 0.01). After PTMV, cardiopulmonary baroreflex sensitivities measured using burst rate and burst incidence were -39.9+/-4.9%/mm Hg and -38.7+/-6.2%/mm Hg, respectively, which were significantly steeper than those before PTMV (-9.2+/-1.1%/mm Hg and -8.4+/-1.1%/mm Hg; p < 0.01). There were significant correlations between muscle sympathetic nerve activity at rest and cardiopulmonary baroreflex sensitivity. PTMV did not affect muscle sympathetic responses to handgrip exercise. These results suggest that patients with mitral stenosis have baseline sympathetic nerve activation, which could result in part from impaired cardiopulmonary baroreflexes.

Adult↗

PubMed2001

Correlation of genetic etiology with response to beta-adrenergic blockade among symptomatic patients with familial long-QT syndrome.

Mutations in any of the five genes KCNQ1, KCNH2, KCNE1, KCNE2, and SCN5A can be responsible for familial long QT syndrome (LQTS), an arrhythmogenic disorder that entails a high risk of sudden death. beta-Adrenergic blocking agents are the first therapeutic choice, and 80% of patients treated with these agents show symptomatic relief; however the remaining 20% do not respond well. We previously performed a nationwide analysis of familial long QT syndrome (LQTS) in Japan and identified 32 mutations in the KCNQ1 and KCNH2 genes. In the present retrospective study, we found that patients carrying mutations in the KCNQ1 gene responded better to beta-adrenergic blocking agents than those with KCNH2 mutations (12 of 13 vs 1 of 5; P = 0.0077, Fisher's exact test). This is a good example of the power of genetic diagnosis to direct the selection of appropriate therapy for patients with diseases of heterogeneous genetic etiology.

Adolescent↗

PubMed2001

Differences in energy metabolism and neuromuscular transmission between 30-Hz and 100-Hz stimulation in rat skeletal muscle.

OBJECTIVE: To examine differences in energy metabolism and neuromuscular transmission failure in rat hindlimb muscles subjected to electric stimulation at different frequencies. DESIGN: Experimental animal study. SETTING: Bioenergetic Research Center at Otsuka Pharmaceutical Company, Otsuka, Japan. ANIMALS: Thirty-two 25-week-old male Wistar-Kyoto rats. INTERVENTIONS: With the rat under general anesthesia, the sciatic nerve was electrically stimulated at 30Hz and 100Hz to induce muscle contraction. MAIN OUTCOME MEASURES: Energy level and intracellular pH of muscles by phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS); M-wave amplitude of muscles by electromyography. RESULTS: During the first 4 minutes under stimulation at 30Hz and at 100Hz, energy level and intracellular pH dropped to their lowest values (p <.05 or p <.01); the values then recovered with time. Recovery rates of energy level and intracellular pH during stimulation at 100Hz were greater than those observed during stimulation at 30Hz. The M-wave amplitude during 100-Hz stimulation was permanently and significantly lower than that measured during 30-Hz stimulation (p <.01), and the recovery rate of M-wave amplitude after stimulation at 100Hz was slower than that after stimulation at 30Hz. CONCLUSION: Neuromuscular transmission failure was greater with 100-Hz stimulation than with 30-Hz stimulation. This finding may account for the rapid recovery of energy level and intracellular pH that occurs with stimulation at 100Hz.

Animals↗

PubMed2001

Enhanced production of leukotrienes by peripheral leukocytes and specific IgE antibodies in patients with chronic obstructive pulmonary disease.

BACKGROUND: How leukotrienes (LTs) and IgE-mediated allergy reflect clinical features in patients with chronic obstructive pulmonary disease (COPD) remains unclear. OBJECTIVE: Our goal was to determine whether LTB4 and LTC4 would correlate with airway obstruction and whether IgE-mediated allergy would influence the generation of LTs and bronchial hyperresponsiveness in patients with COPD. METHODS: We measured the pulmonary function, methacholine bronchial hyperresponsiveness, and generation of LTB4 and LTC4 from peripheral leukocytes stimulated with calcium ionophore A23187 in relation to the presence of specific IgE antibodies against inhalant allergens. RESULTS: The leukocytes of patients with COPD generated significantly more LTB4 (with allergy, P <.001; without allergy, P <.001) and LTC4 (with allergy, P <.001; without allergy, P <.01) than the leukocytes of the control subjects. LTC4 production was significantly higher in the allergic COPD subjects than in the nonallergic COPD patients (P <.01), but the amount of LTB4 generated was not significantly different. FEV(1) significantly correlated with the level of both LTB4 (with allergy, r = -0.556, P =.0375; without allergy, r = -0.731, P =.0046) and LTC4 (with allergy, r = -0.764, P =.0043; without allergy, r = -0.526, P =.0414) generation in COPD. The log(10) of the minimum dose of methacholine was significantly higher in COPD patients without allergy than in those with allergy (P <.05). CONCLUSION: Enhanced LT generation from peripheral leukocytes is observed in patients with COPD, and the presence of specific IgE antibodies against inhalant allergens enhances LTC4 generation, bronchial hyperresponsiveness, and the relationship between LTC4 generation and airway obstruction.

Antibodies, Anti-Idiotypic↗

PubMed2001

Removal of digoxin by column for specific adsorption of beta(2)-microglobulin: a potential use for digoxin intoxication.

BACKGROUND: A beta(2)-microglobulin adsorption column used for the treatment of dialysis-related amyloidosis removes serum beta(2)-microglobulin by recognition of lipophilic residue in the protein. No data are available for the adsorption of the highly lipophilic drug digoxin. METHODS: In vivo clearance of digoxin with the beta(2)-microglobulin column was measured by a single use of the column in 8 patients receiving hemodialysis with a therapeutic level of digoxin. In vitro adsorption was evaluated by use of incubation with adsorbent of the column and digoxin or ranitidine, a hydrophilic drug. Clearance with the beta(2)-microglobulin column was further compared with that obtained by use of activated charcoal in the dogs intoxicated with digoxin. RESULTS: Digoxin concentration was reduced from 1.11 +/- 0.25 ng/mL to 0.57 +/- 0.15 ng/mL at 240 minutes after initiation of hemoperfusion with the column in the patients. Digoxin clearance with the beta(2)-microglobulin column was about 145 +/- 20 mL/min, with a blood flow rate of 160 to 220 mL/min (80% of plasma flow rate). Eighty-five percent of digoxin was adsorbed in vitro, and the capacity of the beta(2)-microglobulin column was not saturated until a toxic level was reached (50 ng/mL). This value was higher than that obtained with use of charcoal. In dogs with digoxin intoxication, digoxin clearance was 38.9 +/- 1.5 mL/min, with a blood flow rate of 50 mL/min (95% of plasma flow rate), which was almost twice as that achieved with charcoal. The degree of thrombocytopenia and leukopenia was small with use of the beta(2)-microglobulin column. CONCLUSION: These data suggested that the beta(2)-microglobulin column selectively adsorbs digoxin. This column is a promising tool for the treatment of digoxin intoxication, especially in patients undergoing hemodialysis.

Adsorption↗

PubMed2001

Influence of age and disease severity on high resolution CT lung densitometry in asthma.

BACKGROUND: Low attenuation areas (LAA) on computed tomographic (CT) scans have been shown to represent emphysematous changes in patients with chronic obstructive pulmonary disease (COPD). However, the significance of LAA is still controversial in patients with asthma. This study was undertaken to assess the usefulness of lung CT densitometry in the detection of airspace enlargement in association with asthma severity. METHODS: Forty five asthmatic subjects and 15 non-smoking controls were studied to determine the influence of age, pulmonary function, and asthma severity on mean lung density (MLD) and the relative area of the lung showing attenuation values less than -950 HU (RA(950)) on high resolution CT (HRCT) scans. RESULTS: In asthmatic patients both MLD and RA(950) correlated with parameters of airflow limitation (%FEV(1), FEV(1)/FVC, %FEF(25-75)) and lung volume (%TLC, %FRC, %RV), but not with lung transfer factor (%TLCO, %TLCO/VA). The results of HRCT lung densitometry also correlated with patient age and severity of asthma. CONCLUSIONS: Decreased CT lung density in non-smoking asthmatics is related to airflow limitation, hyperinflation and aging, but not with lung transfer factor.

Adult↗

PubMed2001

Effect of weight bearing on recovery from nerve injury in skeletal muscle.

We examined the effect of weight bearing (WB) on muscle recovery after nerve injury. Rats were housed in individual cages for 2 wk under WB or hindlimb suspension (HS) after being subjected to sciatic nerve compression for 1 wk. Sham operated on rats served as controls (sham group). We used 31P- and 19F-nuclear magnetic resonance spectroscopy combined with histochemical, physiological, and biochemical techniques to assess the outcome in the three groups. Creatine kinase-BB (CK-BB) mRNA levels expression, CK activity, and type I fiber density in the WB group were elevated compared with those in the HS group. In addition, sciatic functional index, tetanic tension, energy state, and local circulation dynamics of the WB group were greater than those of the HS group. These results suggested that WB plays an important role in muscle regeneration, inhibits the reduction of CK activity, and facilitates the activation of neural recovery, energy state, and local circulation dynamics.

Adenosine Triphosphatases↗

PubMed2001

N-omega-nitro-L-arginine methyl ester increases airway responsiveness to serotonin but not to acetylcholine in cats in vivo.

BACKGROUND: We previously reported that N(omega)-nitro-L-arginine methyl ester (L-NAME) enhances airway responsiveness to inhaled serotonin in cats treated with atropine and propranolol. OBJECTIVE: To further elucidate the role of nitric oxide (NO) in airway responsiveness, we investigated whether L-NAME induces airway hyperresponsiveness to serotonin and acetylcholine (ACh) in animals with intact innervation. METHODS: Cats were anesthetized with pentobarbital sodium (50 mg/kg, i.p.), and mechanically ventilated. To assess airway responsiveness, we measured increase in total pulmonary resistance (RL) produced by delivering serotonin or ACh aerosol to the airway, and determined PC200 (the concentration which caused a 200% increase in RL). RESULTS: The following results were obtained: (1) Airway responsiveness to serotonin was significantly enhanced by the administration of L-NAME (100 mg/kg) in animals treated with atropine and propranolol. (2) Airway responsiveness to serotonin was also significantly enhanced by L- NAME in animals with intact innervation. (3) In contrast, airway responsiveness to ACh was not changed by the addition of L-NAME in cats with intact innervation. CONCLUSION: These results suggest that NO modulates nonspecific airway responsiveness in animals with intact innervation, presumably by a reflex mechanism.

Acetylcholine↗

PubMed2001

Interleukin-1beta stimulates transendothelial mobilization of human peripheral blood mononuclear cells with a potential to differentiate into osteoclasts in the presence of osteoblasts.

There is accumulating evidence that interleukin-1 (IL-1) levels are increased locally at the site of active bone resorption in a variety of diseases including osteoporosis, periodontal disease and rheumatoid arthritis. However, the pathogenic role of IL-1 in bone loss remains to be fully elucidated. We present here additional evidence that IL-1beta enhances endothelial activation and thereby stimulates mobilization of peripheral blood mononuclear cells (PBMCs) from luminal to abluminal spaces across the endothelium. Furthermore, IL-1beta stimulates the differentiation of PBMCs into osteoclast-like cells with bone-resorbing activity in the presence of human osteoblastic SaOS-2 cells without systemic hormones. These findings provide circumstantial evidence for the hypothesis that IL-1beta generated in the bone microenviroment plays a stimulatory role in PBMC mobilization from the peripheral circulation and their subsequent differentiation into osteoclast-like cells in the bone tissue. In addition, the present study supports the notion that osteoclast progenitor cells might be derived from the peripheral circulating blood mononuclear cells in human.

Acid Phosphatase↗

PubMed2001

A patient with severe palindromic rheumatism and frequent episodes of pain.

A 44-year-old man began to experience episodes of joint pain with erythema in his knees, elbows, shoulders, and hands in April 1996. He was diagnosed as having palindromic rheumatism. Due to the increasing frequency and severity of these episodes, he was admitted to our hospital in May 1999. Heat therapy to the affected area produced a rapid improvement in symptoms. In addition, the continued use of physical therapy during symptom-free periods tended to reduce the frequency and severity of pain attacks. We present this case and discuss treatment options in patients with palindromic rheumatism.

Adult↗

PubMed2001

[A case of pulmonary capillary hemangiomatosis].

In March 1995, a 54-year-old woman was admitted to a hospital because of exertional dyspnea and her condition was diagnosed as primary pulmonary hypertension. In September 1996, respiratory difficulty and hemosputum were woted. The chest computed tomographic scan showed diffuse micronodular opacities, and she was admitted to our hospital for examination of other pulmonary conditions giving rise to pulmonary hypertention. However no lung biopsy could be performed, because the pulmonary arterial pressure was too high. Although the patient received medication, she died of progressive right heart failure. The pathological diagnosis at autopsy was pulmonary capillary hemangiomatosis (PCH). Although PCH is a very rare disease that causes secondary pulmonary hypertension, it is important to distinguish it from primary pulmonary hypertension and pulmonary veno-occlusive disease.

Diagnosis, Differential↗

PubMed2001

Disuse osteoporosis.

Reduction of mechanical stress on bone inhibits osteoblast-mediated bone formation and accelerates osteoclast-mediated bone resorption, and leads to what has been called disuse osteoporosis. Prolonged therapeutic bed rest, immobilization due to motor paralysis from injury of the central nervous system or peripheral nerves, application of cast to treat fractures, a common causes of disuse osteoporosis. Imaging diagnosis shows coarse trabecular pattern and thinning of cortical bones. Bone metabolism markers have been used to evaluate bone metabolism. From the viewpoint of bone metabolism, antiresorptive agents should be administered to inhibit bone resorption. Rehabilitation, including bed positioning, therapeutic exercise and electrical stimulation, should be prescribed to subject the atrophied bone to an appropriate level of mechanical stress. In spite of these aggressive and continuous treatments, most cases of disuse osteoporosis require a long time for bone to recover its bone mineral density and strength. Hence, we have to keep in mind that there are no treatments better than prophylaxis of disuse osteoporosis.

Autoimmune Diseases↗