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Biomedical subjects

K Satoh

Publications and source records attributed to K Satoh.

At least 181 records · Page 10Linked to original sources
PubMed2000

A case of rapidly growing ovarian squamous cell carcinoma successfully controlled by weekly paclitaxel-carboplatin administration.

BACKGROUND: Primary squamous cell carcinoma of the ovary is uncommon and has a poor prognosis. Because of its rarity, the effective postoperative treatment is unknown. We describe a remarkable response of this tumor to weekly paclitaxel-carboplatin administration. CASE: A 53-year-old woman had rapidly growing primary squamous cell carcinoma of the ovary that metastasized to the abdominal wall and transverse colon after maximum cytoreductive surgery. The tumor was resistant to primary chemotherapy with cisplatin, vincristine, mitomycin C, and bleomycin. A combination of paclitaxel and carboplatin was used for second-line chemotherapy and was repeated every week. The patient tolerated the chemotherapy well and demonstrated a pathological complete response in the abdominal metastases following the five courses of chemotherapy. CONCLUSION: Weekly paclitaxel-carboplatin administration may be a safe and effective treatment for advanced and rapidly growing ovarian squamous cell carcinoma with primary resistance to chemotherapy.

Abdominal Neoplasms↗
PubMed2000

A PET study of visuomotor learning under optical rotation.

We measured the regional cerebral blood flow (rCBF) in six healthy volunteers with PET (positron emission tomography) and H(15)(2)O to identify the areas of the human brain involved in sensorimotor learning. The learning task was visually guided reaching with sensorimotor discrepancy caused by optical rotation. PET measurements were performed in the early and late stages of the adaptation to the sensorimotor perturbation. Control measurements were obtained during an eye movement task and a reaching task without optical rotation. The rCBF data of each learning stage were compared to those of both control conditions. During the early stage, rCBF increases were detected in the rostral premotor cortex bilaterally, the posterior part of the left superior parietal lobule (SPL), and the right SPL including the intraparietal sulcus (IPS). During the late stage, rCBF increases were detected in the left caudal premotor area, the left supplementary motor area proper, the left SPL, the right SPL including the IPS, and the right postcentral sulcus extending to the inferior parietal lobule. These results reveal that sensorimotor learning accompanies changes in the recruited cortical areas during different stages of the adaptation, reflecting the different functional roles of each area for different components of adaptation, from learning of new sensorimotor coordination to retention or retrieval of acquired coordination.

Adult↗
PubMed2000

Nafamostat mesilate modulates the release of platelet-activating factor during left ventricular assistance with hemofiltration in canine heart failure.

OBJECTIVE: The enhanced generation of various chemical mediators is regarded as one of the mechanisms by which severe heart failure progresses to multiple organ failure. Platelet-activating factor is a phospholipid mediator which plays an important role in inflammatory reactions and circulatory shock. We studied the changes in platelet-activating factor levels in a canine heart failure model treated with a left ventricular assist device and hemofiltration, and assessed the effect of a protease inhibitor, nafamostat mesilate. METHODS: Twenty dogs underwent multiple coronary ligations, and at 2 hours after the ligations they were maintained on left ventricular assist device support with continuous hemofiltration. The animals were divided into two groups: a nafamostat group (n = 10) that received nafamostat mesilate (2 mg/kg/hr), and a control group (n = 10) that received vehicle only. RESULTS: The blood platelet-activating factor level, before coronary ligations, in the control and nafamostat groups was 2.3 +/- 0.4 and 2.0 +/- 0.7 ng/ml, respectively, and the coronary ligations had little effect on the platelet-activating factor. However, after the initiation of left ventricular assist device, the platelet-activating factor in the control group (5.6 +/- 2.2) was significantly higher (p < 0.05) than that in the nafamostat group (1.1 +/- 0.3). Nafamostat administration was also effective in controlling the increase in the blood lactate level. Hemofiltration did not change the platelet-activating factor. CONCLUSIONS: We concluded that platelet-activating factor may play a critical role in the development of severe heart failure with left ventricular assistance, and nafamostat administration is likely to be beneficial in such a critical condition by suppressing the platelet-activating factor level.

Animals↗
PubMed2000

Evaluation of radiotherapeutic response in non-small cell lung cancer patients by technetium-99m MIBT and thallium-201 chloride SPET.

The purpose of this study was to investigate the relationship between technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) accumulation in tumours and response to radiotherapy in non-small cell lung cancer patients in comparison with the findings obtained using thallium-201 chloride (201Tl). Simultaneous dual single-photon emission tomography (SPET) imaging with 600 MBq 99mTc-MIBI and 111 MBq 201Tl was performed in 31 patients with biopsy- or sputum cytology-proven lung cancer. SPET images were acquired 15 min (early) and 2 h (delayed) after injection, and the early ratio, delayed ratio and retention index were measured. The tumours were classified into two groups on the basis of follow-up computed tomography (CT): responders (at least 50% reduction in tumour size) and non-responders (little or no change in tumour size). The mean (+/-SD) values of early ratio, delayed ratio and retention index using 99mTc-MIBI SPET were 3.0+/-1.1, 2.7+/-1.0 and -9.5+/-12.7, respectively, in responders and 2.4+/-0.7, 2.0+/-0.5 and -18.4+/-9.0, respectively, in non-responders. The corresponding values using 201Tl chloride SPET were 3.7+/-1.0, 4.7+/-1.5 and 24.2+/-22.1 in responders and 3.3+/-1.2, 4.0+/-1.3 and 20.4+/-20.5 in nonresponders. Using 99mTc-MIBI, the delayed ratio and retention index in responders were significantly higher than those in non-responders (P<0.01 and P<0.05, respectively). The results of this study indicate that patients with higher delayed ratio and retention index values using 99mTc-MIBI SPET are likely to respond better to radiotherapy than those with lower values. 99mTc-MIBI SPET may give an indication of the short-term response to radiotherapy in patients with non-small cell lung cancer.

Adult↗
PubMed2000

Phenotypic modulation of smooth muscle cells in human cerebral aneurysmal walls.

We used immunohistochemical methods to analyze the phenotypes of smooth muscle cells (SMCs) in human cerebral arteries and aneurysmal walls. Thirty-two aneurysmal walls were studied; 31 aneurysmal walls were resected at operation and 1 aneurysm was obtained at autopsy. Seven control arteries were obtained at autopsy. Semiserial sections were subjected to immunohistochemical staining with antibodies to alpha-smooth muscle actin (alpha-SMA), desmin and smooth muscle myosin heavy chain isoforms: SM1, SM2 and SMemb. In control cerebral arteries, SMCs in the media were strongly immunostained for alpha-SMA, desmin, SM1 and SM2; immunoreactivity for SMemb was faint or weakly positive. SMCs in both non-ruptured and ruptured aneurysmal walls showed no staining for desmin; the expression of alpha-SMA was well preserved. Compared with control cerebral arteries, in 4 of 11 non-ruptured aneurysmal walls, the staining intensity of SMCs for SMemb was clearly increased. In ruptured aneurysmal walls, the expression of SM2 was lower than in control cerebral arteries and non-ruptured aneurysmal walls. Our study suggests that the phenotype of SMCs in aneurysmal walls is different from the contractile type in the media of normal cerebral arteries, at least partially changing to the synthetic type in some non-ruptured aneurysms. SMCs in ruptured aneurysmal walls may have lost both phenotypes before rupture. Phenotypic modulation of SMCs in the aneurysmal walls appears to be related to a remodeling of the aneurysmal wall and to a rupture mechanism.

Actins↗
PubMed2000

Primary gastric lymphoma with spontaneous perforation: report of a case.

Primary gastric lymphoma with spontaneous perforation is rare. We report herein the case of a 53-year-old-man who was admitted to our hospital with severe epigastralgia. Emergency endoscopic examination showed a perforated gastric tumor in the lower body of the greater curvature, and a distal subtotal gastrectomy with lymph node dissection was performed. The resected tumor measured 10.0 x 8.0 cm and was associated with an area of ulceration, 8.0 x 6.0 cm in size, and perforation, 1.0 x 0.5 cm in size. Pathological examination confirmed a diagnosis of B-cell malignant lymphoma of the diffuse, medium-sized cell type. According to the Ann Arbor and Naqvi classifications, the lymphoma was stage II and stage III, respectively. Postoperative adjuvant chemotherapy comprising cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) was given. The patient is currently well with no signs of recurrence, 2 years 4 months after his operation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Outpatient evaluation and treatment of tubal obstruction with selective salpingography and balloon tuboplasty.

OBJECTIVE: To compare selective salpingography and balloon tuboplasty for the treatment of tubal obstruction. DESIGN: A retrospective evaluation of results of women treated for tubal obstruction by outpatient methods at a single center. SETTING: Tertiary-care, university-affiliated hospital. PATIENT(S): A total of 3,424 infertile women, of whom 418 had bilateral tubal obstruction by hysterosalpingography, treated at Nihon Medical Center from 1982 to 1997. INTERVENTION(S): Women with tubal obstructions who had visual evidence of an intact uterine tubal ostium at hysteroscopy were treated by selective salpingography. If selective salpingography could not establish patency, then transcervical balloon tuboplasty was performed with one of three catheter systems. Patients were followed expectantly for 1 year after treatment. MAIN OUTCOME MEASURE(S): Postoperative tubal patency and overall pregnancy rates (PRs) at 1-year of follow-up. RESULT(S): The overall patency rate was 67.5%, with 30% of these patients conceiving (20.2% of all subjects). Selective salpingography was associated with a 35. 7% patency rate, and 27.3% of these patients conceived. Of the subjects who failed selective salpingography and underwent balloon tuboplasty, 66.2% achieved patency, of whom 33% spontaneously conceived. Balloon tuboplasty was effective in restoring patency in many cases after selective salpingography had failed. Statistically significant differences were found between selective salpingography and balloon tuboplasty and for the different balloon tuboplasty catheters in terms of patency rates, while a trend was seen for PRs. CONCLUSION(S): Many women diagnosed as having tubal obstruction can be treated by outpatient methods that do not require general anesthesia. Achieving patency by these methods is associated with high PRs and avoids the need for assisted reproductive technologies in some cases. Balloon tuboplasty is a more effective treatment than selective salpingography. The choice of balloon tuboplasty catheter system may affect success rates.

Adult↗
PubMed2000

Correlations between plasma platelet-activating factor acetylhydrolase (PAF-AH) activity and PAF-AH genotype, age, and atherosclerosis in a Japanese population.

Platelet-activating factor acetylhydrolase (PAF-AH), a plasma enzyme that hydrolyzes PAF and oxidized phospholipids, is thought to be involved in protecting cells against oxidative stress. A G(994) (M allele)-->T (m allele) mutation in the plasma PAF-AH gene, which results in a Val(279)-->Phe substitution in the mature protein, leads to a loss of catalytic activity. To elucidate the relationships among PAF-AH enzyme activity, genotype, age, and atherosclerosis, we assayed these parameters in a large Japanese population (n=3932) that consisted of three groups; a control group (healthy individuals; n=1684), a risk-factor group (individuals having at least one conventional risk factor for atherosclerosis; n=1398), and a diseased group (patients who had suffered a myocardial infarction or stroke; n=850). We observed a significantly increased frequency of the m allele in the diseased group as compared with the control or risk-factor groups. Plasma PAF-AH activity increased significantly with age in women in the control group with the MM and Mm genotypes, and in men in the control group with the MM genotype, but not in men with the Mm genotype. In both the risk-factor and diseased groups, however, no correlation was observed between plasma PAF-AH activity and age in subjects with either genotype. These results suggest that in individuals with the MM genotype, plasma PAF-AH activity may be increased in response to stresses induced by PAF and/or oxidized phospholipids that might accumulate with age, but that this response is not evident or reduced in healthy individuals with the m allele, or in subjects with atherosclerotic disease, or having risk factors. Together with our previous findings, the G(994)-->T mutation in the PAF-AH gene may be one of the genetic determinants for atherosclerotic disease in the Japanese population.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed2000

Murine fetal resorption and experimental pre-eclampsia are induced by both excessive Th1 and Th2 activation.

It has been proposed that immune responses in mammalian normal pregnancy are Th2-like, thereby protecting the fetus and placenta from being rejected. Administration of exogenous Th1 cytokines into pregnant mice is reported to induce feto-placental resorption. However, the effects of exogenous Th2 cytokines and Th2 directed responses in pregnant animals have not been well studied. In this study, we examined IL-4 and IL-12, which play decisive roles in the development of Th2 and Th1 responses, respectively, in the induction of fetal resorption and development of experimental pre-eclampsia. Transfer of either IL-4 and/or IL-12 stimulated splenocytes from BALB/C virgin female mice into BALB/C pregnant mice mated with either C57BL/6 or BALB/C male mice resulted in fetal resorption and glomerular nephritis associated with hypertension and proteinuria. In mice treated with IL-12 stimulated splenocytes, fatty liver degeneration associated with bile retention was observed. These results indicate that both excessive Th1 and Th2 activation contribute to the development of fetal resorption and pre-eclampsia, but that Th1 is critical to the development of liver degeneration.

Adoptive Transfer↗
PubMed2000

Does eradication of Helicobacter pylori reverse atrophic gastritis or intestinal metaplasia? Data from Japan.

In Japan, more reports showing improvement of atrophy or IM after eradication have appeared than reports showing no change. Many authors take biopsy specimens from the lesser and greater curvatures of the antrum and body and incisura angularis and make a histologic assessment using the standardized Updated Sydney System. Sampling errors should be taken into account, however. Interobserver agreement is poor in grading of atrophy. Apart from these problems, it seems almost certain that some patients show improvement or regression of atrophy or IM after eradication. Takizawa et al, evaluating many gastritis specimens, observed that antral IM might regress after eradication in the antral mucosa, where some pyloric glands remained under IM because pyloric glands and IM shared the proliferative zone, and that body IM replacing total fundic glands might hardly regress (T. Takizawa, MD, personal communication). Suto et al showed in an animal model that pseudopyloric glands differentiated into chief and parietal cells. Watanabe et al examined the influence of gastric pH on IM in x-irradiated rats and showed that increased acid secretion was associated with partial disappearance of IM without Paneth cells. Because gastric acid secretion of hypochlorhydric patients with body-predominant gastritis increased into normal range 1 to 6 months after eradication, it is possible that IM may regress in human subjects whose acid-secreting capacity recovers after eradication. The point of no return at which eradication leads to regression of atrophy and IM is not known. It is unknown how long IM takes to regress after eradication. There may be some differences in the characteristics between patients with and without improvement. Factors other than H. pylori (e.g., environmental factors) also should be investigated.

Gastritis, Atrophic↗
PubMed2000

Synthesis and biological activity of N-acylphenothiazines.

Previous studies have demonstrated the relationship between radical intensity and cytotoxic activity in water-soluble compounds. This relationship was investigated in lipophilic compounds. Several N-acylphenothiazines showed higher cytotoxic activity against human leukemic and squamous carcinoma cell lines than phenothiazine, the parent compound. Electron spin resonance (ESR) spectroscopy showed that these active compounds produced much lower amounts of radicals than phenothiazine. Several compounds failed to inhibit the cytopathic effects of human immunodeficiency virus (HIV) infection in MT-4 cells. It suggested that the radical-mediated-mechanisms has not involved in the induction of cytotoxic activity by lipophilic compounds, such as N-acylphenothiazines.

Anti-HIV Agents↗
PubMed2000

Cytotoxic activity of hydrolyzable tannins against human oral tumor cell lines--a possible mechanism.

Hydrolyzable tannins showed higher cytotoxic activity against human oral squamous cell carcinoma and salivary gland tumor cell lines than against normal human gingival fibroblasts, whereas gallic acid, a component unit of tannins, showed much weaker selective cytotoxicity. The cytotoxic activity of dimeric compounds was generally higher than that of monomeric compounds. Macrocyclic ellagitannin oligomers, such as oenothein B, woodfordin C and woodfordin D showed the greatest cytotoxic activity, and their activity (per given number of molecules) was one order higher than those of gallic acid and epigallocatechin gallate, a major component of green tea. These compounds induced apoptotic cell death characterized by DNA fragmentation (as demonstrated by the TUNEL method) and cleavage of cytokeratin 18 by activated caspase(s) (as demonstrated by M30 monoclonal antibody). ESR spectroscopy revealed that these macrocyclic compounds at higher concentrations produced their own radicals and significantly enhanced the radical intensity of sodium ascorbate, possibly by their prooxidant actions. Catalase failed to eliminate their apoptosis-inducing activity, reducing the possibility of the involvement of hydrogen peroxide production in the extracellular fraction. These observations suggested that the antitumor activity of macrocyclic ellagitannin oligomers reported previously might be explained by their apoptosis-inducing activity.

Antineoplastic Agents↗
PubMed2000

Induction of cytotoxicity by chlorogenic acid in human oral tumor cell lines.

Millimolar concentrations of chlorogenic acid (CGA) showed higher cytotoxic activity against human oral squamous cell carcinoma (HSC-2) and salivary gland tumor (HSG) cell lines, as compared with that against human gingival fibroblast (HGF). The cytotoxic activity of CGA was significantly reduced by catalase or CoCl2, but not affected by FeCl3 or CuCl2. ESR spectroscopy showed that higher (millimolar) concentrations of CGA produced radicals under alkaline conditions, acting as a prooxidant, whereas lower concentrations of CGA scavenged superoxide and hydroxyl radical. CGA produced large DNA fragments (as identified by slightly faster migrating band of DNA on agarose gel electrophoresis) and nuclear condensation (as demonstrated by Hoechst (No. 33258) staining) in tumor cell lines. Activation of caspase was demonstrated by staining with M30 monoclonal antibody, which reacts with degradation products of cytokeratin 18. Contact with CGA for at least 6 h was necessary for irreversible cytotoxicity induction. Pretreatment of the cells with caspase 3 inhibitor partially inhibited the cytotoxic action of CGA. These date suggest that CGA induces cytotoxicity in oral tumor cell lines, possibly by hydrogen peroxide-mediated oxidation mechanism.

Anticarcinogenic Agents↗
PubMed2000

The effects of the traditional chinese medicine, "Banxia Houpo Tang (Hange-Koboku To)" on the swallowing reflex in Parkinson's disease.

Swallowing disorder is common in Parkinson's disease (PD). We studied the swallowing disorder in PD, and tested the efficacy of Banxia Houpo Tang (BHT, a Chinese traditional medicine) in improving the swallowing reflex of PD patients. The Swallowing reflex test is a simple method used to detect swallowing disorders in patients with cerebrovascular disease. Because we observed previously that BHT significantly improved the swallowing reflex in cerebrovascular patients, we studied whether BHT was also effective in improving the swallowing disorder in patients with PD. 23 PD patients (13 males, 10 females, mean age 66.0+/-9.3, Hoehn & Yahr (H-Y) mean score = 2.8) were evaluated for swallowing reflex and the concentration of substance-P in their saliva before and after 4 weeks of BHT treatment. The swallowing reflex before treatment was significantly delayed, according to the H-Y score (Spearman's p = 0.014, R2 = 0.463). The swallowing reflex before BHT treatment was 3.66+/-0.98 sec, and after BHT treatment, it improved significantly, to 2.27+/-0.54 sec (p < 0.0001). Substance-P concentration in PD patients saliva before treatment was significantly lower than in healthy controls (p = 0.007), but showed no significant change after BHT treatment. Our research shows that the swallowing reflex is an effective method to evaluate the swallowing disorder in PD. BHT can significantly improved the swallowing reflex in PD patients, and therefore can be a hopeful candidate for preventing aspiration pneumonia in PD.

Aged↗
PubMed2000

Reduction of Q(A) in the dark: Another cause of fluorescence F(o) increases by high temperatures in higher plants.

Increases in the chlorophyll fluorescence F(o) (dark level fluorescence) during heat treatments were studied in various higher plants. Besides the dissociation of light-harvesting chlorophyll a/b protein complexes from the reaction center complex of PS II and inactivation of PS II, dark reduction of Q(A) via plastoquinone (PQ) seemed to be related to the F(o) increase at high temperatures. In potato leaves or green tobacco cultured cells, a part of the F(o) increase was quenched by light, reflecting light-induced oxidation of Q(A) (-) which had been reduced in the dark at high temperatures. Appearance of the F(o) increase due to Q(A) reduction depended on the plant species, and the mechanisms for this are proposed. The reductants seemed to be already present and formed by very brief illumination of the leaves at high temperatures. A ndhB-less mutant of tobacco showed that complex I type NAD(P)H dehydrogenase is not involved in the heat-induced reduction of Q(A). Quite strong inhibition of the Q(A) reduction by diphenyleneiodonium suggests that a flavoenzyme is one of the electron mediator to PQ from the reductant in the stroma. Reversibility of the heat-induced Q(A) reduction suggests that an enzyme(s) involved is activated at high temperatures and mostly returns to an inactive form at room temperature (25 degrees C).

Journal Article↗
PubMed2000

Identification of Photosystem I components from a glaucocystophyte, Cyanophora paradoxa: The PsaD protein has an N-terminal stretch homologous to higher plants.

Thylakoid membranes and Photosystem I (PS I) complexes were isolated from a glaucocystophyte, Cyanophora paradoxa, which is thought to have the most primitive 'plastids', and the proteins related to PS I were examined. The intrinsic light-harvesting chlorophyll protein complexes of PS I (LHC I) were not detected by an immunological method. The PS I complexes consisted of at least eight low-molecular-mass proteins in addition to PS I reaction center proteins. The N-terminal sequence of the PsaD protein has higher homology to that of Chlamydomonas reinhardtii and land plants, than to that of other algae or cyanobacteria. On the other hand, the PsaL sequence has the highest homology to those of cyanobacteria. Taking into account the other sequences of PS I components whose genes are encoded in the cyanelle genome, and the fact that LHC I is not detected, it is concluded that PS I of C. paradoxa has chimeric characteristics of both 'green' lineages and cyanobacteria.

Journal Article↗
PubMed2000

The carbohydrate deposits detected by histochemical methods in the molecular layer of the dentate gyrus in the hippocampal formation of patients with schizophrenia, Down's syndrome and dementia, and aged person.

Post-mortem brain tissue was obtained from 28 patients with brain disorders, of which 15 had clinically diagnosed schizophrenia, 6 Alzheimer type dementia, 5 dementia with tangles and 2 cases of Down's syndrome. The controls were 22 cases from autopsies without brain disorders or with no known episodes of brain disorder. The tissues were stained for the detection of carbohydrate deposits in the hippocampal formation, using lectin, immunohistochemical and conventional staining methods. The staining revealed the existence of spherical deposits in the inner and middle molecular layers of the dentate gyrus in the hippocampal formation which contained fucose, galactose, N-acetyl galactosamine, N-acetyl glucosamine, sialic acid, mannose and chondroitin sulfate. The number of the deposits was higher in patients with brain disorder such as schizophrenia, Alzheimer type dementia, dementia with tangles or Down's syndrome, and in some aged individuals, in comparison to those in younger individuals. No deposits were detected in a few younger or aged individuals. Spherical deposits 3-10 microm in diameter may be an immature form of the corpora amylacea, since they were similar in the histochemical characteristics with lectin, immunohistochemical and conventional staining methods. However, differing staining ability by hematoxylin, periodic acid Schiff's reagent and antibodies against the intracellular degraded proteins such as ubiquitin and tau-protein was observed. The antibodies against ubiquitin and tau-protein showed clear reactivity with the corpora amylacea and no reactivity with spherical deposits, indicating that the corpora amylacea has an intracellular origin and spherical deposits an extracellular matrix origin. The results obtained in this study indicate that not only neuronal degeneration but also unusual glycometabolism in neurons may disturb the neuronal function and cause brain disorders, and that spherical deposits may cause dysfunction of the neuronal network in the dentate gyrus of the hippocampus which is closely linked with recognition and memory functions.

Adult↗