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Biomedical subjects

M Miyata

Publications and source records attributed to M Miyata.

At least 181 records · Page 10Linked to original sources
PubMed1997

Consecutive maintenance of human solitary and hereditary colorectal polyps in SCID mice.

Recently, the sequential changes from adenoma to adenocarcinoma have been well studied in human colorectal carcinogenesis. To study the precise clonal changes from colorectal polyps to cancer, we have established an experimental system to maintain human colorectal polyps in severe combined immunodeficient (SCID) mice that have been improved by the selective inbreeding of C.B17-scid/scid homozygous male and female showing undetectable serum IgG and IgM (< 1 microgram/ml). Two of two solitary polyps from two nonhereditary colon polyp patients, four of five colon polyps from two Peutz-Jeghers' syndrome patients and one polypoid lesion from a familial polyposis coli (FAP) patient grew very slowly but steadily, at approximately one-tenth the rate of their malignant form, (i.e., adenocarcinoma), in the improved SCID mice and were maintained for a long period (more than 2 years), over several mouse generations. However, two polyps from FAP and Peutz-Jeghers' syndrome patients could not be transplanted further because of microinfection at the transplanted site due to incomplete sterilization of original human tumors prior to surgical operation (endoscopic polypectomy). Transplanted colon polyps had a semitransparent, soft and sticky appearance, with cells containing large amounts of mucin. Malignant transformation of human colon polyp to adenocarcinoma has not been observed during the maintenance period (about 2 years) in SCID mice. In the consecutively maintained human colon polyps, however, K-ras mutations were detected at codon 12, while these mutations were not found in their original polyps in the patients.

Adenomatous Polyposis Coli↗
PubMed1997

[Continuous infusion high-dose leucovorin with cisplatin and 5-fluorouracil for a recurrent oropharynx carcinoma].

Cisplatin and leucovorin heighten the activity of 5-fluorouracil by increasing the intracellular concentration of reduced folates. Therefore, we treated the recurrent oropharynx carcinoma case, who had received concurrent chemotherapy with low-dose cisplatin and radiotherapy, with continuous infusion high-dose leucovorin with cisplatin and 5-fluorouracil. Chemotherapy included continuous intravenous infusion of cisplatin (25 mg/m2, days 1 through 5); 5-fluorouracil (600 mg/m2, days 2 through 6); and leucovorin (200 mg/m2, days 1 through 6) administered once about every 4 weeks. Three cycles were performed, and a complete response was achieved. Grade 3 to 4 mucositis, nausea-vomiting, anemia, neutropenia, and thrombocytopenia occurred. Continuous infusion high-dose leucovorin with cisplatin and 5-fluorouracil was effective for this recurrent head and neck carcinoma. However, one must be cautious when comparing this chemotherapy in terms of toxicity.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[A case of supramediastinal neurinoma: its operative approach (via supraclavicular route) and radiographic findings (target sign)].

A 76-year-old female with supramediastinal tumor was admitted. CT scan showed central high density area surrounded by low density area and MR imaging emphasized the same concentric circle. This concentric circle pattern on CT scan and MR imaging is called "Target sign", which is known as characteristic radiographic finding of neurinoma. Therefore we could diagnose her case as mediastinal neurinoma preoperatively. She underwent operation through the supraclavicular approach and the tumor was completely resected. By incising the skin through the modified left hemi-collar incisional line and cutting the clavicula at its central part, we could ensure a good operative field and safely performed this operation without mid-sternotomy or thoracotomy. The supraclavicular approach for the operation of supramediastinal tumor is useful.

Aged↗
PubMed1997

Laparoscopic cholecystectomy in patients with cardiac disease: hemodynamic advantage of the abdominal wall retraction method.

We examined the use of an abdominal wall retraction method instead of pneumoperitoneum in laparoscopic cholecystectomy for patients with cardiac disease to prevent the hemodynamic deterioration associated with pneumoperitoneum. Eight patients with cardiac diseases, mainly valvular or coronary artery diseases, underwent laparoscopic cholecystectomy under hemodynamic monitoring. Five patients without cardiac disease served as controls. As hemodynamic parameters, heart rate, mean systemic arterial pressure (mAP), mean pulmonary arterial pressure (mPAP), central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), and cardiac index (CI) were measured. The patients with cardiac disease showed significantly elevated mPAP and PCWP compared with the control group under pneumoperitoneum, and one patient showed critically decreased CI due to increased tricuspid regurgitation under pneumoperitoneum. These changes, however, were resolved on the abdominal wall retraction. There was no major perioperative complication. This abdominal wall retraction method is, therefore, favorable for patients with underlying cardiac disease to minimize the hemodynamic deterioration during laparoscopic cholecystectomy.

Abdominal Muscles↗
PubMed1997

[The relationship between workers' attitudes towards health, lifestyle and mental health].

In order to investigate the relationship between health practices, various psychosocial factors, and mental health, a survey was conducted by means of a self-rating questionnaire on 424 industrial workers. The questionnaire included items concerning Goldberg's 12 selected items from the Japanese version of the General Health Questionnaire, the Type A scale used in the Framingham study, Breslow's 7 health practices, and other original psychosocial, health practicing items. A total of 391 or 92.2% responded to the questionnaire. Among them, 354 (266 males and 88 females) complete responders to the GHQ were analysed for the present study. As a result, several factors such as decrease in age, perceived present illness, worsening of perceived health status, increase in anxiety concerning health, exacerbation of alcohol and smoking related behaviour, decrease in physical exercise, reduction of Breslow's 7 health practices, perceived stress and difficulty in dealing with stress, increase in stress content, negative and malfunctional coping strategies, and decrease in relaxation were, according to the GHQ scores, related to negative mental health. Furthermore, Type A scores were significantly correlated to GHQ scores, the number of stress factors, and Breslow's 7 health practices in males, but they were weak or had no correlation in females. It is considered that favorable health practices and attitudes towards health might help to maintain positive mental health, but further analysis is needed to determine their causal relationships because of the cross-sectional design of the present study.

Adaptation, Psychological↗
PubMed1997

[Psychosocial evaluation on the correct recollection of periodic medical checkups of workers. 1. The ratio of correctly recalled results of medical checkups].

To investigate the usefulness of a periodic medical checkup at the workplace from the standpoint of remembering the results, a survey was performed by a self-rating questionnaire on 424 industrial workers in a certain manufacturing company. The questionnaire included several items, such as their recalled abnormal medical findings and follow-up toward them, Breslow's 7 health practices, Goldberg's 12 selected items from the Japanese version of the General Health Questionnaire, and other original health related items. The study was conducted a month after the workers received their results. A total of 391 (290 males and 101 females) or 92.2% responded to the questionnaire. Several factors, such as age, gender, the type of occupation, and perceived health status were significantly correlated to the recalled results of medical checkups, but, only age and the way of observing the results were in accordance with the actual results. Only forty-nine percent of the responders correctly remembered their results. Age and perceived health status were significantly correlated to the exact recollection of the results. In particular, those who had poor perceived health status tended to have a wrong understanding of their medical results. Furthermore, there were those with the highest averaged GHQ scores who responded as having some abnormal findings even though no abnormalities were discovered in the medical checkups. On the other hand, there were those with the lowest averaged GHQ scores who answered that they had no abnormal findings even though some abnormalities were revealed in the medical checkups. The frequency of correct follow-up of the results was lower than the exact recalling of the results. In addition, those who made a mistake in the follow-up were inclined to have an optimistic view. Therefore, comprehensive health care for precise recalling of the results of medical checkups should be required to improve abnormal findings or maintain a good health status.

Adult↗
PubMed1997

Isopoly-L-ornithine derivative as nucleic acid model.

Isopoly-L-ornithine derivatives of thymine, and thymidine were found to hardly interact with poly A. Conformational studies of the oligomers with CD and NMR revealed that stable intramolecular hydrogen bonding was formed between the thymine base and the ornithine unit.

DNA↗
PubMed1997

Substances reactive with mannose-binding protein (MBP) in sera of patients with rheumatoid arthritis.

OBJECTIVES: In order to evaluate the role of mannose-binding protein (MBP) in rheumatoid arthritis, we characterized MBP-binding substances in sera of patients with this disease. METHODS: An enzyme linked immunosorbent assay (ELISA) was used to detect MBP-binding substances in sera of patients with RA. We applied the sera of two RA patients to an immobilized MBP column, and by means of both ELISA and molecular sieve chromatography, examined the substances that bound to MBP. MBP-MASP complexes were added to the fractions containing the binding substances, and C4-consuming activity was examined. RESULTS: Sera of patients with RA showed stronger MBP binding on ELISA than did those of normal controls. In the case of RA sera, both IgG was IgM-RF eluted from the MBP column, whereas with normal controls, only IgG was obtained. The results of molecular sieve chromatography showed that the binding substances of RA patients consisted of immune complexes containing IgG and IgM-RF. These substances were specifically bound to MBP, and once bound, the MBP-MASP complexes were then able to consume C4. CONCLUSION: MBP binds to immune complexes consisting of IgG and IgM-RF, and probably recognizes either the mannose moiety of IgM-RF or the N-acetyl-glucosamine of agalactosyl IgG. When this occurs in RA patients, the lectin pathway would then be activated.

Antigen-Antibody Complex↗
PubMed1996

Cyclic AMP induces apolipoprotein E binding activity and promotes cholesterol efflux from a macrophage cell line to apolipoprotein acceptors.

RAW 264 mouse macrophage cells were stably transfected with human apolipoprotein E (apoE) expression vectors. Clonal derivatives were characterized for expression of the human apoE2, apoE3, and apoE4 isoforms. An apoE4-expressing clonal cell line and a non-expressing clonal control cell line were loaded overnight with either [3H]cholesterol or [3H]choline. The cells were washed and incubated for 24 h in serum-free medium with or without the addition of 8-bromo-cyclic AMP (8-Br-cAMP). Only the apoE-secreting cells and only in the presence of 8-Br-cAMP released large amounts of labeled cholesterol or phosphatidylcholine into the medium. Mass analyses of cellular free and esterified cholesterol confirmed the results of the labeling studies; a decrease in cellular cholesterol content was observed in the 8-Br-cAMP-treated apoE-secreting cells, concurrent with an increase in cholesterol found in the medium. FPLC analysis of the medium demonstrated that 8-Br-cAMP treatment of the apoE-secreting cells led to an increased size fraction and amount of a peak of secreted cholesterol which comigrated with apoE. The 8-Br-cAMP-mediated increase in cholesterol efflux was also observed in non-apoE-secreting cells incubated with exogenous apoE or apoAI, and the effect of apoE was saturable. The apoE2, apoE3, and apoE4 isoforms were equally efficient in promoting 8-Br-cAMP-dependent cholesterol efflux. Reductive methylation of apoE abolished its ability to promote 8-Br-cAMP-dependent cholesterol efflux. Brefeldin A and monensin, inhibitors of protein processing through the Golgi, both blocked the 8-Br-cAMP stimulation of cholesterol efflux to exogenous apoE. 8-Br-cAMP induced specific apoE and apoAI binding, but not apoE degradation, by the RAW cells. We present a model wherein cAMP induces a membrane apolipoprotein receptor that does not lead to endocytosis and degradation, but instead promotes the transfer of lipids to apolipoproteins, which can then be released from the cell.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1996

NF-kappa B is induced in the nuclei of cultured rat aortic smooth muscle cells by stimulation of various growth factors.

We investigated whether induction of transcription factor NF-kappa B is involved in the proliferation of cultured rat aortic smooth muscle cell using electrophoretic mobility shift assay and immunocytochemistry. NF-kappa B was induced in the nucleus in a dose-dependent manner when the smooth muscle cells were stimulated by various growth factors such as PDGF-BB, bFGF, EGF and IGF-1, but not growth inhibitors such as TGF-beta and IFN-gamma. Among growth factors, PDGF-BB and bFGF, more potent growth stimulators, induced higher kappa B binding activity than EGF or IGF-1. These evidences were also supported by the results obtained with immunocytochemistry. Immunocytochemistry also showed that the induced NF-kappa B contained p50 and p65. These results suggest that NF-kappa B induction may be involved in the proliferation of vascular smooth muscle cell.

Animals↗
PubMed1996

Structure of flavoprotein FP390 from a luminescent bacterium Photobacterium phosphoreum refined at 2.7 A resolution.

The three-dimensional structure of a flavoprotein, FP(390), from a luminescent bacterium, Photobacterium phosphoreum, solved by the molecular-replacement method, was refined to an R factor of 24.0% for 17 433 independent reflections, from 6.0 to 2.7 A resolution, collected by synchrotron radiation. The asymmetric unit of the crystal (space group P4(3)22, a = b = 76.8 and c = 242 A) contains two monomer molecules related by a non-crystallographic twofold axis to form a dimer. There are two Q-flavin [flavin mononucleotide (FMN) with myristic acid] molecules in FP(390) monomer. One of them is located at the interface of dimer which is bound to both monomer and the another is at the molecular surface. The electron density of myristic acids of Q-flavins at the dimer interface in both monomer are weak and unclear, showing the possibility that the Q-flavins bound in this site are not a single species but a mixture of two components, 6-(3"-myristic acid)-FMN and 6-(4"- myristic acid)-FMN.

Journal Article↗
PubMed1996

Decreased E-cadherin expression is associated with haematogenous recurrence and poor prognosis in patients with squamous cell carcinoma of the oesophagus.

Reduced expression of E-cadherin is associated with tumour invasiveness and metastasis. To elucidate whether E-cadherin expression correlates with clinical outcome in patients with oesophageal cancer, 62 patients were investigated immunohistochemically using an anti-E-cadherin monoclonal antibody (HECD-1). Eight patients had normal levels of expression in the tumour, 25 had tumours that expressed high levels (50 per cent or more tumour cells staining positive for E-cadherin) and 29 had tumours expressing low levels (less than 50 per cent of cells expressing E-cadherin). Patients with normally expressing tumours had a better prognosis at 3 years than those with low-expressing tumours (P < 0.05). Postoperative death was correlated significantly with lymphatic invasion, lymph node metastasis, E-cadherin expression and depth of invasion (P < 0.05). Furthermore, haematogenous recurrence was correlated with E-cadherin expression (rs = 0.38, P < 0.01) and blood vessel invasion (rs = 0.28, P < 0.05). These results suggest that evaluation of E-cadherin immunoreactivity may predict haematogenous recurrence and poor prognosis in patients with oesophageal cancer.

Adult↗
PubMed1996

Effect of pneumoperitoneum on interatrial pressure gradient during laparoscopic cholecystectomy.

Alterations of the left atrial/right atrial pressure gradient were determined using a Swan-Ganz thermodilution catheter in 20 patients who underwent laparoscopic cholecystectomy with 12 mmHg pneumoperitoneum (LAP) and 13 patients who underwent minilaparotomy cholecystectomy (MINI). Right and left atrial pressures were both elevated by pneumoperitoneum. A diminished or reversed left/right interatrial pressure gradient was recognized during pneumoperitoneum in 4 of the 20 patients (20%) in the LAP group, whereas it was not recognized during operation in any of the 13 patients in the MINI group. Evaluation of the elevation of intrathoracic pressure during pneumoperitoneum using peak inspiratory airway pressure or pulmonary arterial pressure could not predict the occurrence of this paradoxical interatrial pressure gradient.

Atrial Function, Left↗
PubMed1996

High serum concentration of lipoprotein(a) is a risk factor for restenosis after percutaneous transluminal coronary angioplasty in Japanese patients with single-vessel disease.

To determine the relation between the concentration of lipoprotein(a) [Lp(a)] and restenosis after percutaneous transluminal coronary angioplasty (PTCA) in Japan, we studied 80 consecutive patients with single-vessel disease who successfully underwent PTCA. All were evaluated by follow-up angiography a mean of 6.9 months after PTCA and were divided into the restenosis (30 patients) and the non-restenosis (50 patients) groups. The serum Lp(a) concentration of 29 +/- 17 mg/dl in the restenosis group was significantly higher than that of 17 +/- 14 mg/dl in the nonrestenosis group (p < 0.01). Multiple logistic regression analysis for risk factors revealed a significant correlation between restenosis and Lp(a) (p < 0.003). The serum Lp(a) concentration was positively correlated with the coronary artery percent stenosis at the time of follow-up angiography (r = 0.32, p < 0.01). High serum concentration of Lp(a) is therefore a risk factor for restenosis after PTCA in Japan.

Adult↗
PubMed1996

Gastric syphilis: polymerase chain reaction detection of treponemal DNA in pseudolymphomatous lesions.

Syphilis is an unexpected diagnosis in the stomach. To establish the diagnosis, evidence of Treponema pallidum in the gastric lesion is necessary. However, it is sometimes difficult to prove the presence of the organisms by conventional methods. The authors describe two cases of early gastric syphilis with pseudolymphomatous histology in which T pallidum gene was detected by the polymerase chain reaction (PCR) using paraffin biopsy sections. The gastric lesion of each case endoscopically and histologically simulated that of malignant lymphoma. However, no clonality was proved by immunohistochemistry or PCR gene rearrangement analysis. No spirochetal organisms were detected with certainty by Warthin-Starry silver stain, whereas the organisms were shown by immunofluorescent stain in one patient. A PCR study showed the treponemal DNA in both patients, and its validity was supported by a direct sequencing and a restriction enzyme digestion. Positive results of serological tests for syphilis and regression of the lesions after antisyphilitic treatment were confirmatory of the diagnosis. Gastric syphilis should be considered as a differential diagnosis when an atypical lymphoid infiltrate fails to show monoclonality. The present PCR method would be helpful in showing T pallidum using routinely processed small biopsy specimens as the tissue source.

Adult↗