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Biomedical subjects

M Sakurai

Publications and source records attributed to M Sakurai.

At least 145 records · Page 8Linked to original sources
PubMed1999

Shift work-related problems in 16-h night shift nurses (1): Development of an automated data processing system for questionnaires, heart rate, physical activity and posture.

To assess the shift work-related problems associated with a 16-h night shift in a two-shift system, we took the following important factors into consideration; the interaction between circadian rhythms and the longer night shift, the type of morningness and eveningness experienced, the subjective sleep feeling, the subjects' daily behavior, the effectiveness of taking a nap during the long night shift, and finally the effectiveness of using several different kinds of measuring devices. Included among the measuring devices used were a standard questionnaire, repetitive self-assessment of subjective symptoms and daily behavior at short intervals, and a continuous recording of such objective indices as physical activity and heart rate. A potential problem lies in the fact that field studies that use such measures tend to produce a mass of data, and are thus faced with the accompanying technical problem of analyzing such a large amount of data (time, effort and cost). To solve the data analysis problem, we developed an automated data processing system. Through the use of an image scanner with a paper feeder, standard paper, an optical character recognition function and common application software, we were able to analyze a mass of data continuously and automatically within a short time. Our system should prove useful for field studies that produce a large amount of data collected with several different kinds of measuring devices.

Algorithms↗
PubMed1999

Shift work-related problems in 16-h night shift nurses (2): Effects on subjective symptoms, physical activity, heart rate, and sleep.

We compared the shift work-related problems between 16-h night shift and 8-h evening/night shifts among nurses in a university hospital with respect to subjective symptoms, physical activity, heart rate (HR), and sleep. The nurses of one group (n = 20) worked a 16-h night shift under a rotating two-shift system, while those of the other group (n = 20) worked an 8-h evening or night shift under a rotating three-shift system. The 16-h night shift was staffed by three or four nurses who alternately took a 2-h nap during the shift, and had at least one day off after each shift. Subjective symptoms and daily behavior were measured every 30 min by the nurses before, during, after each shift as well as during days off using a time-budget method. Also, physical activity, heart rate (HR), and posture were recorded during shifts. The results showed similar or lower levels of sleepiness, difficulty in concentration, fatigue, physical activity, and HR during the 16-h shift compared to the 8-h shifts. No differences in subjective symptoms between the two shift schedules were observed before or after the shifts or during days off. The main sleep was longer after the shifts and during days off in the 16-h shift group than in the 8-h shift group. Our results suggest that the work-related problems in 16-h night shift nurses may not be excessively greater than those in 8-h evening/night shift nurses, as long as appropriate countermeasures are taken during and after the extended shift.

Adult↗
PubMed1999

Enhanced cytotoxic interaction between 5-fluorouracil and 4-hydroperoxycyclophosphamide against L1210 murine leukemic cells: applicability to ex vivo purging.

Eradication of contaminated tumor cells in bone marrow is a matter of utmost concern in the setting of autologous bone marrow transplantation. 4-Hydroperoxycyclophosphamide (4-HC) is often used for ex vivo chemical purging of contaminated tumor cells in bone marrow. The marrow from patients pretreated with 5-fluorouracil (5-FU) is enriched with multifactor-responsive high proliferative potential colony-forming cells. To develop an efficient ex vivo chemical purging system, we evaluated interaction between 4-HC and 5-FU. We investigated the antitumor effect of cyclophosphamide, a mother compound of 4-HC, and 5-FU against L1210 ascites tumor in B6D2F1 mice. The median lifespan of the mice treated with 4-HC or 5-FU alone was 8 and 12 days, respectively. The combination of both drugs significantly extended the median lifespan to 18.5 days. The median effect plot analysis indicated a synergistic cytotoxic interaction between 5-FU and 4-HC in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl terazolium bromide (MTT) assay. Clonogenic assay also showed that combination of 4-HC and 5-FU significantly reduced L1210 leukemic colonies to 20% of untreated control. Bone marrow cells from the mice treated with 5-FU at 150 mg/kg body weight was resistant to 4-HC at concentrations as high as 0.2 microgram/ml, which was more than 70% inhibitory concentration for colony formation in L1210 leukemic cells. Findings suggest that sequential treatment with in vivo 5-FU followed by ex vivo 4-HC could selectively enhance antitumor effects of 4-HC in tumor cells remaining in bone marrow.

Animals↗
PubMed1999

[Fungal infection in patients with serious disease. Risk analysis of fungal infection].

BACKGROUND: Candidemia is still a major source of high morbidity and mortality in severely disease patients. However, the etiology and risk factor is still unknown. PURPOSE: To evaluate the risk factor of fungal infection in intensive care patients. SUBJECTS AND METHOD: 505 patients who stayed in the intensive care unit of the Critical Care Center, Kyorin University more than 10 days between May 1, 1997 to June 31, 1998 were studied. They were divided into 7 groups: 1) trauma (injury severity score<10), 2) burn (burn index<10), 3) cerebro-vascular disease (unconsciousness 15), were in a coma, and had severe injury of lung parenchyme with chest AIS 3 or higher. In these serious patients, it is necessary to make a rapid diagnosis and treatment based on the surveillance culture and serological examination of sputum and urine for occult fungal infection.

Antifungal Agents↗
PubMed1999

[High-dose chemotherapy followed by peripheral blood stem cell transplantation in advanced extragonadal germ cell tumor--a case report].

We reported the experience of high-dose chemotherapy (HDC) combined with peripheral stem cell transplantation (PBSCT) in 29 years-old man with advanced retroperitoneal germ cell tumor accompanied with left supraclavicular lymph node metastases, who obtained complete remission after comprehensive treatment. The initial levels of serum AFP, hCG and beta-hCG were high at 30.2 ng/ml, 14,000 mIU/ml and 66 ng/ml, respectively. After 3 courses of chemotherapy (BEP regimen), while left supraclavicular lymph node swelling was disappeared, the retroperitoneal mass lesion persisted on CT scan. Not all of 3 markers fell to the normal range. After myelosuppressive chemotherapy (etoposide 500 mg/m2 Day 1-3), PBSCs were collected by two consecutive apheresises on Day 17 and 18. In total, 19.5 x 10(6)/kg CD 34 positive cells were obtained. The patient underwent PBSCT (all CD 34 positive cells were infused) on Day 0 following HDC (CBDCA 250 mg/m2/day, etoposide 300 mg/m2/day, IFM 1.5 g/m2/day, Day-7(-)-3, respectively). He became severely leukopenic and thrombopenic with nadir of 200/microliter on Day 6 and 2 x 10(4)/microliter on Day 2, respectively. By administration of platelet transfusion and G-CSF, the white blood cell counts and thrombocyte counts recovered to 6,400/microliter and 4.1 x 10(4)/microliter on Day 10, respectively. Microbiologically enterocolic and respiratory tract infections occurred with elevated body temperature (> 40 degrees C). Antibiotic and antimycotic treatments were continued until disappearance of all clinical and microbiological evidence. He was kept for 10 days in clean room. After HDC, all markers fell to the normal range, but the retroperitoneal residual mass still persisted. Resection of the residual mass and retroperitoneal lymph node dissection were performed with pathological examination revealing tissue necrosis without viable cell. The patient has survived with no sign of the disease for 9 months.

Adult↗
PubMed1999

TMC-171A,B,C and TMC-154, novel polyketide antibiotics produced by Gliocladium sp. TC 1304 and TC 1282.

Four new antibiotics, TMC-171A (2), B (3), C (4) and TMC-154 (5) have been isolated from the fermentation of fungal strains Gliocladium sp. TC 1304 and TC 1282, respectively. Spectroscopic and degradation studies have shown that TMC-171s and TMC-154 were new members of the TMC-151 class of antibiotics, unique polyketides modified with a D-mannose and a D-mannitol or a D-arabitol. These compounds showed moderate cytotoxicity to various tumor cell lines.

Anti-Bacterial Agents↗
PubMed1999

Type A aortic dissection involving a right-sided aortic arch.

We report a rare case of a 39-year-old man with type A aortic dissection involving a right-sided aortic arch with the symptom of vascular ring. Computed tomography scanning and angiography were performed to define the extent of the dissection and the anatomy of the branching vessels. The ascending aorta was replaced through a median sternotomy and right thoracotomy using a hypothermic cardiopulmonary bypass associated with selective cerebral perfusion and partial circulatory arrest, and his symptom of vascular ring disappeared postoperatively.

Adult↗
PubMed1999

[Resected case of synchronous double cancer of lung and ovarium].

A 45-year-old woman was admitted to our department for a tumor shadow in the right lung on chest rentogenogram and chest CT. Detailed examination led to the diagnosis of simultaneous lung cancer and ovarian cancer. No abnormality was found in the liver. Serum AFP level was 113.8 ng/ml preoperatively, but deceased upper lobectomy of the right lung to 11.4 ng/ml on the 15th day postoperatively. Immunohistochemical study revealed positive staining of carcinoma cells with anti AFP serum.

Adenocarcinoma↗
PubMed1999

Rapid normalization of interleukin-8 production after low-density lipoprotein apheresis in steroid-resistant nephrotic syndrome.

BACKGROUND: Low-density lipoprotein apheresis (LDL-A) treatment combined with steroids demonstrated significant improvement of nephrotic proteinuria in steroid- or immunosuppressive-resistant patients from focal and segmental glomerulosclerosis (FGS). The mechanisms of the effect of LDL-A in nephrotic syndrome (NS) are unknown, but a reduction in inflammatory cytokines and chemokines secreted from macrophages has been supposed. METHODS: Serum levels of interleukin (IL)-8, tumor necrosis factor-alpha (TNF-alpha), and monocyte chemoattractant protein-1 (MCP-1) were measured by enzyme-linked immunosorbent assay in 27 patients with NS [13 with FGS and 14 with minimal change nephrotic syndrome (MCNS)] before and after LDL-A and in 13 age-matched, healthy controls. We also selected three FGS patients who were resistant to steroid therapy for at least one month and who had undergone six LDL-A procedures. The effects of steroids and LDL-A on the production of IL-8, TNF-alpha, and MCP-1 by peripheral blood mononuclear cells (PBMCs) were also determined in some patients. RESULTS: In NS, the serum levels of IL-8 and TNF-alpha, but not MCP-1, were significantly higher than in healthy controls. After LDL-A, IL-8 and TNF-alpha tended to decrease. IL-8 production by lipopolysaccharide (LPS)-stimulated PBMC, mainly adherent cells, was significantly reduced in both the steroid-resistant FGS group and nontreated NS group compared with controls, but TNF-alpha production was reduced in the only FGS group. After LDL-A, only IL-8 production recovered to the control group level. CONCLUSION: Significant amelioration of IL-8 production independent of any effect of steroids on LPS-stimulated PBMCs may reflect a beneficial effect of LDL-A in normalizing the function of circulating monocytes in steroid-resistant FGS.

Blood Component Removal↗
PubMed1999

[Clinical experience of extracorporeal shock wave lithotripsy for elderly patients with upper urinary stones].

This study was aimed to evaluate the usefulness and feasibility of extracorporeal shock wave lithotripsy (ESWL) performed in elderly patients. ESWL by Triptor X-1 was used to treat 530 patients with upper urinary tract stones from 1991 to 1998. Sixty one (11.5%) of them were aged 70 years and older. The results of ESWL treatment in this elderly group were compared retrospectively with those in 122 patients aged from 20 to 39 and 243 patients aged from 40 to 59. Although the elderly had a higher incidence of preoperative risk factors, the postoperative complication rates were similar among all groups. The stone-free rate and the success rate at one month in the elderly group were 67.2% and 92.5%, respectively, which were similar to those in the younger groups. These results suggested that ESWL offered a safe and effective means of treating upper urinary tract stones in elderly patients.

Adult↗
PubMed1999

[Smooth muscle myosin of SM1 and SM2 isoforms expressing human neuroblastoma cell line of MP-N-MS].

Human neuroblastoma (NB) cell lines have at least three morphological appearance of neuroblastic (N-type), substrate-adhessive (S-type) and intermediate(I) cells. Our previous study revealed S-type cells expressed alpha-smooth muscle actin, desmin and/or basic-calponin, indicating the plausible smooth muscle cell characteristics of S-type cells. In this study, a new human NB cell line, MP-N-MS, was established from bone marrow metastasis of a one year and six-month old girl with advanced NB, originating from right adrenal gland. Morphology of this cell line is composed of S-type cells. MP-N-MS was identified as a NB cell line by surface membrane antigen analysis and MYCN gene amplification. EWS-FLI1 and EWS-ERG chimeric products, observed in Ewing family tumors, were not detected by RT-PCR (reverse transcriptase-polymerase chain reaction). In cytoskeletal protein analysis, alpha-smooth muscle actin and basic calponin of smooth muscle cell markers were detected. Furthermore, smooth myosin of SM1 isoform was identified in MP-N-MS cell line by immunofluorescence, Western blot and RT-PCR, whereas smooth myosin of SM2 was detected by RT-PCR. MP-N-MS is the first cell line, showing SM1 and SM2 isoforms. The presence of smooth muscle myosin of SM1 and SM2 isoforms in MP-N-MS demonstrated the mature smooth muscle phenotype of this NB cell line, and the ability of NB cells to differentiate into smooth muscle cell.

Cell Differentiation↗
PubMed1999

[Clinical evaluation of granisetron (BRL43694) in nausea and vomiting induced by anticancer drugs--pediatrics].

Granisetron has been used widely for the prevention and treatment of nausea and vomiting associated with anticancer drugs in adult patients with cancer. This multi-center open study was conducted to study the efficacy, safety and usefulness of granisetron in children with cancer. Among 166 evaluable patients, the efficacy rate (percentage of "remarkably effective" or "effective") was 84.9% and the usefulness rate (percentage of "extremely useful" or "useful") was 87.3%. No serious adverse effects were observed. As granisetron 40 micrograms/kg had an excellent antiemetic effect and a high degree of safety against nausea and vomiting associated with anticancer drugs, it was shown to be useful for children with cancer.

Adolescent↗
PubMed1999

[Idiopathic pulmonary fibrosis of the upper lobe: a case report].

A 26-year-old man was admitted to our hospital complaining of exertional dyspnea. Chest x-ray films disclosed reticulonodular shadows predominantly in the upper fields of both lungs, but no apical cap. Lung biopsy specimens obtained from the upper lobe by video-assisted thoracoscopy revealed subpleural elasto-fibrosis. Also, specimens obtained from the lower lobes disclosed micro-honeycombing due to peri-lobular fibrosis resembling usual interstitial pneumonia. Although pneumothorax occurred repeatedly, the lungs reinflated on each occasion without artificial intervention. Similar radiographic findings had been obtained on the patient's father, who died of idiopathic pulmonary fibrosis at the age of 56. Idiopathic pulmonary upper lobe fibrosis was conclusively diagnosed because the patient exhibited most of the features originally described by Amitani et al.

Adult↗
PubMed1999

Delayed cytotoxicity of 6-mercaptopurine is compatible with mitotic death caused by DNA damage due to incorporation of 6-thioguanine into DNA as 6-thioguanine nucleotide.

Many protocol studies have shown that low dose 6-mercaptopurine (6MP) in maintenance chemotherapy for childhood acute lymphoblastic leukemia (ALL) can be utilized to cure the disease. Mitotic or reproductive cell death has been recognized after G2 arrest when cells are treated with antitumor agents. The precise mechanism of mode of action of 6MP still remains unclear. We found delayed cytotoxic effect of 6MP in P388 murine leukemic cells. Morphological study showed that 6MP induced delayed death was characterized by an enlargement of cell size and multinucleated nuclei. Agarose gel electrophoresis of fragmented DNA from cells treated with 6MP showed the typical ladder pattern. These findings were compatible with mitotic death. Our results make us hypothesize that the delayed cytotoxicity of 6MP is one of the drug induced mitotic deaths caused by DNA damage due to incorporation of 6-thioguanine (6TG) into DNA as thioguanine nucleotide (TGN). Mitotic death may be a mechanism for killing the cycling cells from residual leukemic cells in G0 or long G1 phases in the treatment of childhood ALL.

Animals↗
PubMed1999

Quantitative analysis and in situ localization of human telomerase RNA in chronic liver disease and hepatocellular carcinoma.

Telomerase is a specialized type of reverse transcriptase that catalyzes the synthesis and extension of telomeric DNA. High levels of telomerase activity have been detected in most hepatocellular carcinoma (HCC) tissues; very weak telomerase activity is, however, detected in approximately half of nontumorous chronic liver disease tissues. The purpose of this study was to investigate the possible source of this weak telomerase activity in these tissues using quantitative competitive reverse transcription (RT)-polymerase chain reaction (PCR) and in situ RT-PCR. Competitive RT-PCR indicated that the relative amount of human telomerase RNA (hTR) was significantly higher in chronic hepatitis or liver cirrhosis compared with the normal liver (p < 0.005), and in HCC compared with the normal liver (p < 0.001) and with chronic hepatitis or liver cirrhosis (p < 0.0001). In the normal liver tissue, hTR was detected by in situ RT-PCR in occasional sinusoidal cells and nuclei of occasional hepatocytes. In tumor-free liver or tumor-bearing liver, hTR was detected in sinusoidal cells, infiltrating lymphocytes, occasional proliferative bile ductal epithelial cells, and the nuclei of occasional hepatocytes. In HCC, hTR was detected in nuclei of all HCC cells as an intense signal and in sinusoidal cells. These results indicate that the amount of hTR increases in the nuclei of hepatocytes during hepatocarcinogenesis, and that the cells associated with the weak telomerase activity in approximately half of the nontumorous chronic liver lesions are mainly migrating lymphocytes and sinusoidal cells.

Adult↗
PubMed1998

Consensus phosphorylation sites of human GABA(c)/GABArho receptors are not critical for inhibition by protein kinase C activation.

The mechanism of inhibition of human GABA(C)/GABArho receptors by protein kinase C (PKC) activation was investigated in Xenopus oocytes. Phorbol 12-myristate 13 acetate (PMA), a potent PKC activator, at 25 nM inhibited the currents through GABArho2 receptors, which have one consensus phosphorylation site by PKC in the predicted intracellular loops. The time-courses and amplitudes of inhibition were not significantly different from those occurring through GABArho1 receptors, which have six such sites. The inhibitory effect of PMA was also observed after removing each consensus phosphorylation site in both GABArho1 and rho2 receptors by site-directed mutagenesis. These results suggest that phosphorylation of consensus sites in the intracellular loops is not involved in the inhibition of human GABA(C)/GABArho receptors by PKC activation.

Animals↗