Biomedical subjects

Y Mochizuki

Publications and source records attributed to Y Mochizuki.

At least 37 records · Page 2Linked to original sources

PubMed2001

Cx32 but not Cx26 is associated with tight junctions in primary cultures of rat hepatocytes.

On freeze-fracture replicas, gap junctions are frequently colocalized with tight junctions. In this study, to elucidate the relationship between gap- and tight-junction proteins, we investigated the localization of gap-junction proteins Cx32 and Cx26 and tight-junction proteins occludin, claudin-1, ZO-1, and ZO-2 in primary cultured rat hepatocytes, using confocal laser microscopy. In hepatocytes cultured in 2% DMSO and 10(-7) M glucagon medium, Cx32- but not Cx26-immunoreactive lines were observed on the most subapical plasma membrane at cell borders, while on the basolateral membrane both Cx32- and Cx26-positive spots were colocalized. Occludin-, claudin-1-, ZO-1-, and ZO-2-immunoreactive lines were also linearly observed on the most subapical plasma membrane and were colocalized with only Cx32-immunoreactive lines. In freeze-fracture analysis, many small gap-junction plaques were observed within a well-developed tight-junction strand network. The fence function of tight junctions in the cells, as examined by diffusion of labeled sphingomyelin, was well maintained. We also carried out Western blotting for Cx32 following immunoprecipitation with anti-occludin, anti-claudin-1, or anti-ZO-1 antibodies. Cx32 was detectable in all immunoprecipitates. These results suggest that Cx32 gap junctions, but not those with Cx26, are closely coordinated with the expression and function of tight junctions in hepatocytes and that Cx32 gap-junction formation may affect cell polarity through modification of tight-junction expression.

Animals↗

PubMed2001

Maintenance of connexin 32 and 26 expression in primary cultured rat hepatocytes treated with 3-acetylpyridine.

BACKGROUND AND AIM: We recently reported that primary rat hepatocytes treated with 3-acetylpyridine (3-AP), an analog of nicotinic acid, could maintain hepatic differentiated functions such as albumin, tryptophan 2,3-dioxygenase, and connexin 32 (Cx32) mRNA expressions for more than a week. In the present experiment, we investigated the expression of not only Cx32, but also Cx26 in cells treated with 10 mmol/L 3-AP in detail. METHODS: We examined the expression of Cx32 and Cx26 in primary rat hepatocytes by using the methods of immunocytochemistry, immunoelectron microscopy, northern blotting, and dye-transfer. RESULTS: The hepatocytes treated with 3-AP were polygonal with a large cytoplasm from day 3, and were maintained for approximately 2 weeks, whereas the cells without 3-AP began to die from day 4. Immunocytochemically in the cells with 3-AP, many Cx32- and Cx26-positive spots were observed between most adjacent cells, and the intensity of positive spots increased with time in culture, whereas in the cells without 3-AP, Cx32- and Cx26-positive spots disappeared at day 4. Furthermore, most Cx26-positive spots were colocalized with Cx32-positive ones. The amounts of Cx32 and Cx26 mRNA transcripts in the cells with 3-AP at day 14 were more than 80% and approximately 30% of those of Cx32 and Cx26 mRNA transcripts in the cells at day 1, respectively. Gap junctional intercellular communication was maintained in the cells treated with 3-AP at day 8, although it was lost in the cells without 3-AP. CONCLUSION: Thus, the addition of 10 mmol/L 3-AP to the medium enhanced the maintenance of Cx32 and Cx26 expression, which is one of the hepatic differentiated functions, in primary rat hepatocytes for a long time.

Animals↗

PubMed2001

Correlations between P300 components and regional cerebral blood flows.

To evaluate the diagnostic importance of event-related potential P300, the correlation between P300 and regional cerebral blood flow (rCBF) was investigated in various brain regions in patients with multiple cerebral infarction (16 cases), chronic alcoholism (11 cases) and Alzheimer's disease (5 cases) and in seven healthy people. Cognitive function was also evaluated by mini-mental state examination. P300 latency and rCBF was measured by recording of evoked potentials using an oddball paradigm and stable xenon computed tomographic scanning, respectively. A significant (P<0.05) negative correlation between P300 and rCBF was observed in the thalamus in patients with multiple cerebral infarction and chronic alcoholism. In addition, a significant (P<0.01) negative correlation between P300 latency and the mini-mental state examination score and positive correlation between rCBF in the thalamus and the mini-mental state examination score were observed. These findings suggest that P300 latency is associated with rCBF in the thalamus and cognitive function.

Aged↗

PubMed2001

Recent trend of increase in proportion of low birthweight infants in Japan.

BACKGROUND: The proportion of low birthweight babies (LBW: 1500-2499 g) in Japan decreased steadily from 1950 to the 1970s. However, since then it has started to increase consistently, the reason for which has not been discussed in detail. METHODS: Trends of birthweight and the two known factors for low birthweight (maternal smoking, and pre-pregnancy weight) were analysed with vital statistics, national nutritional and smoking prevalence survey data. RESULTS: Increase in term LBW due to intrauterine growth retardation, is the major risk factor for the overall increase since the 1970s. The increase of smoking prevalence in women in their thirties started in the 1970s, while that for women in their twenties started in the 1960s. The decrease of body mass index for women in their thirties also began in the 1970s, while that for women in their twenties began in the 1960s. The ratio of delivery to mothers in their thirties to mothers in their twenties has increased more than threefold compared to the late 1970s. CONCLUSIONS: Since the 1970s increase in smoking prevalence and decrease in body mass index in young women, especially those in their thirties, appeared to be the major factors involved in the increase in LBW babies.

Adult↗

PubMed2001

FDG accumulation in aortic walls.

A 65-year-old woman with no symptoms underwent whole-body F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for cancer screening. FDG accumulation was detected incidentally in her arterial walls, including the aortic wall. She had no history of inflammatory or cardiovascular disease. Although accumulation of FDG is well recognized in the aortic wall when vasculitis is present, this patient showed no symptoms of active vasculitis during the 22-month follow-up period after the PET study. The aortic wall might be a site where FDG accumulates physiologically in elderly persons.

Aged↗

PubMed2001

F-18 FDG uptake in endometrial cancer.

Endometrial cancer, which is one of the most common malignant gynecologic diseases, was detected by F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in a 60-year-old woman with abdominal distention. FDG PET revealed heterogeneous and marked accumulation in the endometrium, which was thought to represent endometrial cancer. In addition, focal intense accumulation of FDG in both lungs suggestive of lung metastases were noted. Endometrial cancer and lung metastases were confirmed by endometrial biopsy and computed tomography of the chest, respectively.

Endometrial Neoplasms↗

PubMed2001

Occludin and claudin-1 concentrate in the midbody of immortalized mouse hepatocytes during cell division.

It has been believed that epithelial cells maintain tight junctions at all times, including during cell division, to provide a continuous epithelial seal. However, changes in localization of integral tight junction proteins during cell division have not been examined. In this study, using SV40-immortalized mouse hepatocytes transfected with human Cx32 cDNA, in which tight junction strands and the endogenous tight junction proteins occludin, claudin-1, ZO-1, and ZO-2 were induced, we examined changes in localization of the tight junction proteins at all stages of cell division. All tight junction proteins were present between mitotic cells and neighboring cells throughout cell division. In late telophase, the integral tight junction proteins occludin and claudin-1, but not the cytoplasmic proteins ZO-1 and ZO-2, were concentrated in the midbody between the daughter cells and were observed at cell borders between the daugher and neighboring cells. These results indicate that the integral tight junction proteins are regulated in a different manner from the cytoplasmic proteins ZO-1 and ZO-2 during cytokinesis.

Animals↗

PubMed2001

Gene expression profiles in Ciona intestinalis tailbud embryos.

A set of 3423 expressed sequence tags derived from the Ciona intestinalis tailbud embryos was categorized into 1213 independent clusters. When compared with DNA Data Bank of Japan database, 502 clusters of them showed significant matches to reported proteins with distinct function, whereas 184 lacked sufficient information to be categorized (including reported proteins with undefined function) and 527 had no significant similarities to known proteins. Sequence similarity analyses of the 502 clusters in relation to the biosynthetic function, as well as the structure of the message population at this stage, demonstrated that 390 of them were associated with functions that many kinds of cells use, 85 with cell-cell communication and 27 with transcription factors and other gene regulatory proteins. All of the 1213 clusters were subjected to whole-mount in situ hybridization to analyze the gene expression profiles at this stage. A total of 387 clusters showed expression specific to a certain tissue or organ; 149 showed epidermis-specific expression; 34 were specific to the nervous system; 29 to endoderm; 112 to mesenchyme; 32 to notochord; and 31 to muscle. Many genes were also specifically expressed in multiple tissues. The study also highlighted characteristic gene expression profiles dependent on the tissues. In addition, several genes showed intriguing expression patterns that have not been reported previously; for example, four genes were expressed specifically in the nerve cord cells and one gene was expressed only in the posterior part of muscle cells. This study provides molecular markers for each of the tissues and/or organs that constitutes the Ciona tailbud embryo. The sequence information will also be used for further genome scientific approach to explore molecular mechanisms involved in the formation of one of the most primitive chordate body plans.

Animals↗

PubMed2001

Corticotroph cell adenoma without typical manifestations of Cushing's disease presenting with cavernous sinus syndrome following pituitary apoplexy.

This report presents a unique case of corticotroph cell adenoma in a 30-year-old man without acromegaly or features typical of Cushing's disease, who developed cavernous sinus syndrome following pituitary apoplexy. Magnetic resonance imaging revealed a large intrasellar/suprasellar mass with pituitary hemorrhage and extension of a hematoma to the anterior base of the skull. Urgent transnasal pituitary surgery revealed an acidophilic pituitary adenoma, with immunoreactivity for ACTH and GH and expression of proopiomelanocortin (POMC) and GH messenger ribonucleic acid (mRNA) demonstrated by in situ hybridization. To our knowledge, a silent corticotroph cell adenoma with GH production has never been reported. This type of adenoma may potentially enlarge and develop tumoral hemorrhage because it is free of endocrinological symptoms.

Adenoma↗

PubMed2001

Relation between smoking prevalence and various social factors in Japan.

Although the smoking prevalence among women is significantly low compared to that among men in Japan, the prevalence in young Japanese women has been steadily increasing recently. The relationship between the prevalence of smoking among the general population and various social factors was investigated with a special emphasis regarding the influence of household size on the smoking prevalence of young Japanese women. Thirty-one thousand and six hundreds twenty-seven subjects of 20 years and older were randomly selected from the general population of Japan. The Ministry of Health and Welfare, Japan planned and conducted the survey. Subjects were divided into male and female, and smoking prevalence was investigated in terms of age, place of residence, occupation and household size factors. Statistical analyses were performed using chi-square test and multiple logistic regression. Multiple logistic regression analyses suggested that for men there was a strong relationship between becoming a smoker and living in a municipality with a smaller population, and that for women who were living in a municipality with a larger population. For women, as the size of a household increased from living alone to a two- or three-generation household, the tendency to becoming a smoker decreased, but this tendency was not observed among men. As to reasons for quitting smoking, more women than men living in two- and three-generation households gave "family's advice" as a major reason (p < 0.01). The steady replacement of the traditional three-generation household by smaller households in Japan may lead to an increase in the number of young women who smoke.

Adult↗

PubMed2001

[Usefulness of OPCAB from the viewpoint of fluctuations in the level of blood natriuretic peptides].

Fluctuations in the level of blood natriuretic peptides (ANP and BNP) were compared between 41 patients who underwent conventional coronary artery bypass (CCAB) and 19 patients who underwent off-pump coronary artery bypass (OPCAB). A blood sample was collected before surgery, and 6, 12 and 24 hours; 2, 3, 5 and 7 days; and 1 month after the end of extracorporeal circulation. There were no significant differences in left ventricular ejection fraction (LVEF) before and after surgery in either group or between the two groups. On average, 3.3 +/- 1.0 bypass grafts were used for the CCAB group, and 2.2 +/- 0.8 grafts for the OPCAB group. Furthermore, the maximum postoperative creatine phosphokinase-MB (CK-MB) level for the CCAB group was 49.1 +/- 17.5 IU/l, whereas that for the OPCAB group was significantly lower at 23.2 +/- 24.8 IU/l. The preoperative level of blood ANP for the CCAB group was 24.6 +/- 19.9 pg/ml while that for the OPCAB group was 39.3 +/- 29.5 pg/ml, but there was no significant difference between the two groups. In both groups, the level of blood ANP reached a peak three days after the end of extracorporeal circulation and then decreased after that point. Although the level of blood ANP for the OPCAB group decreased to 51.4 +/- 26.4 pg/ml one month after the end of extracorporeal circulation, that for the CCAB group one month after the end of extracorporeal circulation remained significantly high at 61.3 +/- 30.6 pg/ml, when compared to that before surgery. Furthermore, the preoperative level of blood BNP for the CCAB group was 40.0 +/- 35.2 pg/ml and that for the OPCAB group was 75.5 +/- 59.7 pg/ml, but there was no significant difference between the two groups. Then, in both groups, the level of blood BNP reached a peak 2-5 days after the end of extracorporeal circulation and then decreased after that. Whereas the level of blood BNP for the OPCAB group decreased to 96.4 +/- 56.0 pg/ml one month after the end of extracorporeal circulation, that for the CCAB group one month after the end of extracorporeal circulation remained significantly high at 160.3 +/- 106.2 pg/ml when compared to that before surgery. The levels of ANP and BNP increased postoperatively for both OPCAB and CCAB groups since the following events caused a great degree of stress on the heart: general anesthesia, cardiac herniation, stabilizer compression, regional blood flow blockage and reperfusion injury. Although the level of natriuretic peptides for the CCAB group remained high one month after the end of surgical stress, that for the OPCAB group returned to near the preoperative level one month later, thus supporting the notion that OPCAB is less invasive.

Aged↗

PubMed2001

Coronary artery bypass in dialysis patients.

This study evaluated the operative outcome of dialysis patients undergoing coronary artery bypass (CAB). In the past 6 years, 38 dialysis patients with a mean age of 57.5 years underwent CAB. Thirty-one operations were elective, and 7 were nonelective operations. Thirty-two operations were performed under cardiac arrest, 3 operations were performed under fibrillatory arrest, and 3 operations were performed without cardiopulmonary bypass. The average number of bypass grafts was 2.8. In all patients, the internal thoracic artery was used. Hospital mortality was 5.3%. Actuarial survival rates at 1, 3, and 5 years including all causes of death were 88%, 80%, and 72%, respectively. With improvements in perioperative management, coronary artery bypass can be performed with acceptable mortality and morbidity in dialysis patients. Complete revascularization without cardiopulmonary bypass is the ideal method and will increase in usage. However, the conventional CAB also provides acceptable results.

Adult↗

PubMed2001

[A case of rheumatoid lung disease in which lung involvement preceded arthritis].

A 75-year-old man was admitted because of dyspnea on exertion and diffuse pulmonary interstitial shadows. An open lung biopsy revealed unclassified interstitial pneumonia. The abnormal shadow subsided spontaneously. Three years later, however, rheumatoid arthritis developed with a simultaneous relapse of interstitial pneumonitis, which was alleviated by steroid therapy. We report here the rheumatoid lung disease that preceded the onset of arthritis, together with a review of the literature.

Aged↗

PubMed2001

[A case of mucoid impaction of bronchi (MIB) due to Schizophyllum commune].

A 51-year-old woman was admitted because of a productive cough. Atelectasis of the left upper lobe and eosinophilia were noted. The atelectasis was resolved after bronchoscopic removal of the mucous plug. Pathologically, it consisted of eosinophil accumulation with hyphae. Cultures of sputum samples revealed Schizophyllum commune. We diagnosed this case as mucoid impaction of bronchi due to S. commune. Eight months later, a productive cough developed again. Chest radiography showed atelectasis of the right middle lobe. Cultures of bronchial washings yielded S. commune and Aspergillus niger. The atelectasis was resolved by four months of administration of itraconazole (200 mg daily).

Aspergillosis, Allergic Bronchopulmonary↗

PubMed2001

[A case of Mycobacterium intracellulare lung disease occurred in a middle-aged man who complained hemoptysis with normal chest roentogenogram].

A 45-year-old man visited our clinic because of intermittent bloody sputum. The chest roentogenogram was normal, but the high-resolution computed tomography (HRCT) showed very small nodules and bronchiolitis adjacent to pleura in the upper right lung field. The bronchoscopic examination revealed blood-streaked bronchial secretion in the right upper lobe bronchus, and the cultures of the sputa and the bronchial washing specimen showed acid-fast bacilli identified as Mycobacterium intracellulare by DNA-DNA hybridization (DDH) method. This case was diagnosed as Mycobacterium intracellulare lung disease. The patient received isoniazid, levofloxacin, and clarithromycin for three years without clinical and bacteriological improvement. His hemoptysis and the number of colonies recovered from sputum cultures decreased without any medication later. The serial chest roentogenograms and HRCTs have showed no changes for 6 years after the diagnosis. This case may show some clues to elucidate the mechanism of the onset of Mycobacterium intracellulare lung disease without predisposing conditions.

Hemoptysis↗

PubMed2001

[Pulmonary nocardiosis associated with nephrotic syndrome].

A 70-year-old man treated for 6 months with prednisolone for nephrotic syndrome, was referred to our pulmonary division because of a nodule in the right lower lung field. Nocardia asteroides was isolated from the culture of the percutaneous lung aspiration, and the case was diagnosed as pulmonary nocardiosis. The lesion disappeared after 2 months of therapy with sulfamethoxazole/trimethoprim (1,600 mg/320 mg once a day). Though it had been given prophylactically (800 mg/160 mg twice a week) for the prevention of pneumocystis carinii pneumonitis.

Aged↗

PubMed2001

[Severe Klebsiella pneumonia improved by endotoxin adsorption and continuous hemodiafiltration].

A 57-year-old man who had past history of alcoholic hepatitis was admitted to our hospital because of fever, general malaise and dyspnea. Chest X-ray films and computed tomographic scans disclosed lobar pneumonia of the right upper lobe. Laboratory tests showed hypoxemia and renal dysfunction. Artificial ventilation, endotoxin adsorption (PMX) and continuous hemodiafiltration (CHDF) were started on the day after admission because of the appearance of progressive renal failure, hypotension and disturbance of consciousness. A diagnosis of septic multiple organ failure was made on the basis of a blood and sputum culture that revealed a K. pneumoniae infection. After the initiation of intensive therapy, the patient's general condition improved and artificial ventilation, PMX and CHDF were withdrawn. However, MRSA was isolated from sputum specimens and a lung abscess developed. In spite of vancomycin administration, the effect was limited. The patient underwent a right upper lobectomy and was discharged. The prognosis of bacteremic K. pneumoniae pneumonia in alcoholics is reported to be very poor. In our case, it is suggested that PMX and CHDF contributed to the improvement of the clinical course.

Adsorption↗

PubMed2001

[The validity of repeated mail surveys concerning smoking habits for Japanese physicians].

PURPOSE: A cross-sectional study of smoking prevalence among medical doctors was performed using questionnaires. Mailing four times proved essential in order to obtain a reasonable number of responses from the subjects. The objective of the present study was to analyze the smoking characteristics of the subjects who returned the questionnaires after the second to fourth mailings. METHODS: A set of an anonymous questionnaire and a letter from the President of the Japan Medical Association (JMA) requesting cooperation was mailed with a return envelope with the subject's name and address written to 3,000 male and 1,500 female doctors randomly selected from the roster membership of the JMA. The survey was conducted between February and June 2000. RESULTS: The collection rate after the first mailing was 66%, while the subtotal collection rate for the second through fourth mailings was 21%, bringing the grand-total to 87%. The total prevalence of smoking among the subjects who had sent back the questionnaire on the second to fourth mailings was approximately 1.5 times higher than for those who had sent back the questionnaire after the initial mailing for both male and female subjects. As to other characteristics of the subjects who only responded after the second to fourth mailings were: working in hospitals (odds ratios; male: 1.39, female: 1.47), not giving smoking cessation guidance (odds ratio; male: 0.58), and not recognizing the idea that doctors should not smoke (odds ratio; female: 0.67). CONCLUSIONS: The results suggested that for future surveys on smoking to be conducted in academic institutions or work-places, efforts to obtain responses from those who do not answer the first attempt should take into consideration these points.

Adult↗