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S Takemura

Publications and source records attributed to S Takemura.

At least 19 recordsLinked to original sources
PubMed2005

Brown-Séquard-plus syndrome due to stab injury: a case report.

STUDY DESIGN: Case report. OBJECTIVE: To describe the mechanism of injury in this case and its clinical features. Magnetic resonance (MR) images of hemorrhage in spinal cord injury due to stab wound are discussed. METHODS: We describe the case of a 21-year-old woman who was stabbed in the right side of her neck and developed left-sided Brown-Séquard syndrome plus loss of bilateral proprioceptive sensation. Neither plain radiographs nor computed tomography of the cervical spine demonstrated any foreign bodies or fractures of the cervical spine. T2-weighted cervical MR images confirm spinal cord hemiresection at C5-C6. RESULTS: MR imaging was performed serially at 4 days, 4 weeks, and 8 weeks after trauma. The signal pattern of the spinal cord at the site of injury varied iso, iso, and low on T1-weighted consecutive images. Meanwhile, high signal intensity on T2-weighted images was consistent during the 8 weeks after incidence of trauma. A T2-weighted sagittal image showed a tiny spot of low intensity in the high signal band at the site of penetration, demonstrating hemosiderin formation in the spinal cord. The patient was treated conservatively and, recovered from Frankel grade C to grade D. CONCLUSION: Spinal cord injuries (SCI) following stab wounds are rare. MR imaging is definitely useful for recording and monitoring the pathology of SCI.

Adult↗
PubMed2005

Recurrence rate and transplantability after liver resection in patients with hepatocellular carcinoma who initially met transplantation criteria.

To understand the recurrence rate and transplantability after liver resection (LR), which are essential factors to predict the prognosis of initial resection and salvage transplantation for hepatocellular carcinoma (HCC), we reviewed the clinical records of 279 consecutive HCC patients who met the Milan criteria and underwent LR between 1990 and 2000. Recurrence-free survival rates after 1, 2, 3, 5, and 10 years following LR were 84%, 62%, 49%, 29%, and 17%, respectively. Multivariate analysis using clinical factors such as age, sex, histological differentiation, serum levels of alpha-fetoprotein and 7S domain of type IV collagen (7S collagen), platelet counts, indocyanin green retention test after 15 minutes, and type of LR (resection of one or more segments, or less than one segment) revealed 7S collagen to be a independent factor that significantly affects recurrence-free survival. Yearly recurrence rates up to 5 years after resection ranged from 14% to 27%, averaging 20%. Concerning 169 patients who underwent tests for 7S collagen, the average yearly recurrence rate (27%) in patients with 7S collagen levels 8.0 ng/mL or higher was remarkably greater than that in the patients with levels less than 8.0 ng/mL (16%). The transplantability rate at the time of recurrence meeting the Milan criteria was roughly 60%. There were no pre-LR factors that significantly predicted transplantability. This result indicates that patients with lower 7S collagen levels are more eligible for initial LR and then salvage LT rather than primary LT.

Adult↗
PubMed2003

Choledocholithiasis caused by migration of a surgical clip into the biliary tract following laparoscopic cholecystectomy.

As experience with laparoscopic cholecystectomy (LC) has increased, so have the number and variety of complications. We report a case of choledocholithiasis caused by migration of a surgical clip applied during LC. A 57-year-old Japanese man who had undergone LC 6 years previously was referred to our hospital with pruritus and jaundice. Magnetic resonance cholangiopancreatography and ultrasonography revealed a solid mass in the common hepatic duct and dilatation of the intrahepatic bile ducts. Abdominal arteriography demonstrated interruption of the right hepatic artery by surgical clips. Five days after a biopsy of the mass was performed through a percutaneous transhepatic biliary drainage tube, the mass moved to the terminus of the common bile duct along with one of the surgical clips. A basket catheter was used to remove the mass via endoscopy. Despite the fact that other clips in the common hepatic duct were partially exposed, the patient has been well for 2 years with no additional interventions.

Bile Ducts, Intrahepatic↗
PubMed2002

Smoking behavior, initiating and cessation factors among Japanese nurses: a cohort study.

The prevalence of smoking among Japanese nurses, specially in their twenties, is higher than that among the general female population. To examine smoking behavior, smoking initiating and cessation factors, we conducted a cohort study through questionnaire survey, targeting nurses (n=1572) working at 11 hospitals located in Tokyo metropolitan area. The first survey was conducted using a confidential questionnaire on smoking, followed by a second survey conducted in the same manner on the same subjects two years later. As to smoking status after two years, 8% (95%CI=1.5%) started smoking and 6% (95%CI=1.4%) quitted resulting in a 2% increase in the prevalence of current smoking. The average nicotine dependence for nurses who were smokers in the two surveys rose from 3.9 to 4.3 (P<0.05). Smoking behavior of mother, friends, or superiors at work had a significant influence on smoking behavior of nurses. As to smoking cessation factors, the idea that women and medical workers should not smoke, and living with family each had a significant influence. Considering the fact that 6% of nurses in this study succeeded in quitting smoking within two years, it is required that anti-smoking education be conducted at medical institutions to decrease the prevalence of current smoking among the nurses in Japan.

Adult↗
PubMed2001

Differential localization of non-muscle myosin II isoforms and phosphorylated regulatory light chains in human MRC-5 fibroblasts.

We investigated the localization of non-muscle myosin II isoforms and mono- (at serine 19) and diphosphorylated (at serine 19 and threonine 18) regulatory light chains (RLCs) in motile and non-motile MRC-5 fibroblasts. In migrating cells, myosin IIA localized to the lamella and throughout the posterior region. Myosin IIB colocalized with myosin IIA to the posterior region except at the very end. Diphosphorylated RLCs were detected in the restricted region where myosin IIA was enriched. In non-motile cells, myosin IIA was enriched in peripheral stress fibers with diphosphorylated RLCs, but myosin IIB was not. Our results suggest that myosin IIA may be highly activated by diphosphorylation of RLCs and primarily involved in cell migration.

Cell Movement↗
PubMed2001

Escape from tolerance of organic nitrate by induction of cytochrome P450.

The mechanism of organic nitrate tolerance is poorly defined. We studied the rat P450-catalyzed conversion of organic nitrate to nitric oxide (NO) by purified P450 isoforms relationship between P450 expression and nitrate tolerance following continuous infusion of organic nitrates in rats. The hypotensive effect of an nitroglycerin (NTG) bolus injection was abolished in rats that had been previously provided a continuous 48 h infusion of NTG. This effect was accompanied by a gradual but marked decrease in plasma and urinary nitrate levels following a peak at 18-24 h. Nitrate tolerance was reversible; the decline in the hypotensive effect and P450 levels observed after 2 d of continuous infusion was followed by restoration to control levels 2 d after cessation of the infusion. Similarly, the hypotensive action disappeared in P450-depleted, and -inhibited rats. At 48 h after infusion, NTG-induced NO generation of the vessels increased in acetone (a P450 inducer) -pretreated rats. The appearance and disappearance of P450 paralleled the conversion of organic nitrates to NO. Our observations indicate that nitrate tolerance is in large part the result of decreased P450 expression and activity. Interventions that maintain or increase P450 activity may be a strategy to provide relief from ischemic conditions in humans.

Animals↗
PubMed2001

T cell activation in rheumatoid synovium is B cell dependent.

Rheumatoid arthritis results from a T cell-driven inflammation in the synovial membrane that is frequently associated with the formation of tertiary lymphoid structures. The significance of this extranodal lymphoid neogenesis is unknown. Microdissection was used to isolate CD4 T cells residing in synovial tissue T cell/B cell follicles. CD4 T cells with identical TCR sequences were represented in independent, nonadjacent follicles, suggesting recognition of the same Ag in different germinal centers. When adoptively transferred into rheumatoid arthritis synovium-SCID mouse chimeras, these CD4 T cell clones enhanced the production of IFN-gamma, IL-1beta, and TNF-alpha. In vivo activity of adoptively transferred CD4 T cells required matching of HLA-DRB1 alleles and also the presence of T cell/B cell follicles. HLA-DRB1-matched synovial tissues that were infiltrated by T cells, macrophages, and dendritic cells, but that lacked B cells, did not support the activation of adoptively transferred CD4 T cell clones, raising the possibility that B cells provided a critical function in T cell activation or harbored the relevant Ag. Dependence of T cell activation on B cells was confirmed in B cell depletion studies. Treatment of chimeric mice with anti-CD20 mAb inhibited the production of IFN-gamma and IL-1beta, indicating that APCs other than B cells could not substitute in maintaining T cell activation. The central role of B cells in synovial inflammation identifies them as excellent targets for immunosuppressive therapy.

Adult↗
PubMed2001

Lymphoid neogenesis in rheumatoid synovitis.

In rheumatoid arthritis (RA), tissue-infiltrating lymphocytes can be arranged in sophisticated organizations that resemble microstructures usually formed in secondary lymphoid organs. Molecular pathways and host risk factors involved in this process of lymphoid neogenesis remain to be defined. In a series of 64 synovial tissue biopsies, lymphoid follicles with germinal centers (GCs) were found in 23.4% of the patients. Follicular dendritic cells (FDCs) were exclusively present in tissues with GCs, suggesting that the recruitment or in situ maturation of FDCs is a critical factor for GC formation in the synovial membrane. Primary follicles were absent, emphasizing the role of Ag recognition in the generation of inflammation-associated lymphoid organogenesis. Multivariate logistic regression analysis of tissue cytokines and chemokines identified two parameters, in situ transcription of lymphotoxin (LT)-beta and of B lymphocyte chemoattractant (BLC; BLC/CXCL13), that were predictors for FDC recruitment and synovial GC formation. LT-beta and BLC/CXCL13 were found to be independent variables that could, in part, compensate for each other to facilitate GC formation. Prediction models incorporating in situ transcription of LT-beta and BLC/CXCL13 had high negative yet moderate positive predictive values, suggesting that LT-beta and BLC/CXCL13 are necessary but not sufficient. LT-beta protein was detected on a subset of mantle zone and GC B cells, but also on T cells in follicular structures. BLC/CXCL13 was produced by FDCs in follicular centers, but was predominantly found in endothelial cells and synovial fibroblasts, suggesting heterotypic signaling between cells of the synovial membrane and infiltrating lymphocytes in regulating extranodal lymphoid neogenesis.

Arthritis, Rheumatoid↗
PubMed2001

The influence of lifestyle and health status factors on sleep loss among the Japanese general population.

STUDY OBJECTIVE: To examine the relationship between lifestyle, health status factors and sleep loss. DESIGN: A cross-sectional questionnaire survey conducted by the Ministry of Health and Welfare, Japan. SETTING: N/A. PATIENTS OR PARTICIPANTS: Approximately 30,000 subjects selected from the general population in Japan. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: This study indicated that approximately 28% of the general population sleep less than 6 hours nightly and approximately 65% sleep less than 7 hours. However, approximately 80% of the population reported getting sufficient sleep. Multiple logistic regression analysis showed that being females, being of younger age, living in an urban environment, being unemployed, and having an unhealthy lifestyle (i.e., lack of exercise, poor health status, and irregular eating habits) were associated with sleep loss. CONCLUSION: In this study, sleep loss was found to be associated with having an unhealthy lifestyle and being in poor general health. These findings suggest that health education and promotion of a healthy lifestyle should be advocated.

Adult↗
PubMed2001

CD4+,CD28- T cells in rheumatoid arthritis patients combine features of the innate and adaptive immune systems.

OBJECTIVE: To determine whether CD4+,CD28- T cells, which are expanded in patients with rheumatoid arthritis (RA), express receptors that typically regulate the function of natural killer (NK) cells. METHODS: Expression of the NK cell surface molecules CD158, p70, CD94, CD161, and CD8alpha on T cell subsets was determined by multicolor flow cytometric analysis of peripheral blood mononuclear cells from 36 RA patients. Expression of CD161 on tissue-infiltrating CD4 T cells was determined by 2-color immunohistochemistry analysis of synovial tissue samples. RESULTS: Killer cell-inhibitory receptors (KIR) and killer cell-activating receptors (KAR) were exclusively expressed on CD4+,CD28- T cells, with the CD158b molecule being the most frequently detected isoform. A coordinated mechanism inducing KIR/KAR expression was suggested by similarities in the expression of CD158b on CD4 and CD8 T cells. CD4+,CD28- T cells were also positive for CD8-alphaalpha homodimers, another characteristic shared with NK cells. Of the C-type lectin NK cell receptors (NK receptors), CD94 was consistently absent, but CD161 was found on a CD4 T cell population that is significantly expanded in RA patients (P = 0.01). Involvement in disease of NK receptor-expressing CD4 T cells was suggested by the presence of CD4+,CD161+ T cells in follicular microstructures typical of rheumatoid synovitis. CONCLUSION: Patients with RA have an expanded and unusual subset of CD4 T cells that infiltrates the tissue lesions and is characterized by a deficiency of CD28, the expression of CD8-alphaalpha homodimers, and the expression of several types of HLA class I-recognizing NK receptors. CD4 T cells bearing NK receptors can bridge functions of the innate and adaptive immune systems, such as responsiveness to specific antigen, rapid release of interferon-gamma, cytotoxicity, independence from classic costimulatory pathways, and integration of multiple activating and inhibitory signals to control effector functions.

Antigens, Surface↗
PubMed2001

Smoking behavior and related factors among Japanese nursing students: a cohort study.

BACKGROUND: Although there have been several surveys on smoking behavior among Japanese nursing students, most have been cross-sectional studies. No longitudinal studies, such as a prospective cohort study, have ever been carried out. We therefore conducted a cohort study on, and analyzed smoking behavior and related factors among, Japanese nursing students. METHODS: A survey on smoking behavior using a confidential questionnaire was conducted on nursing students at two vocational schools of nursing and two nursing colleges/universities located in the Tokyo metropolitan area. Another survey was subsequently conducted in the same manner among the same subjects 1 year later. The surveys were conducted between 1997 and 1999. RESULTS: Over the 1-year period, the prevalence of smoking among nursing students increased by 10% for students at the vocational schools of nursing (n = 224) and by 3% for students at the nursing colleges/universities (n = 222). The average score for nicotine dependence for students who were daily smokers at both time points rose from 3.6 to 4.4 (P < 0.05). Two factors found to significantly predict smoking behavior were having friends who smoke and living alone. CONCLUSION: Smoking prevalence is increasing among Japanese nursing students. Smoking prevention and cessation interventions should be instituted in all nursing training programs.

Adult↗
PubMed2001

Mutated SEA-D227A-conjugated antibodies greatly enhance antitumor activity against MUC1-expressing bile duct carcinoma.

For the purpose of establishing a new adoptive immunotherapy for bile duct carcinoma (BDC), we have directed our attention to superantigens (SAgs), the most potent known activators of T lymphocytes. In our previous study, staphylococcal enterotoxin A (SEA) was conjugated chemically with MUSE11 mAb, which recognizes the MUC1 cancer-associated antigen, and shown to enhance the specific cytotoxic activity of T-LAK cells against MUC1-expressing BDC cells (TFK-1) in vitro and in vivo. However, it is probable that SEA might cause side-effects because of nonspecific binding to class II positive cells. In order to overcome these, we generated mutated SEA (mSEA) by changing Asp at position 227 of native SEA to Ala, which has reduced affinity to MHC class II molecules, but retains the potential for T cell activation. When mSEA-D227A was administered to rabbits to examine effects on blood pressure, 500 times more mSEA-D227A was tolerated than native SEA. This prompted us to construct a mSEA-D227A-conjugated mAb, reactive with MUC1. It augmented the antitumor activity of T-LAK cells significantly, and furthermore, mSEA-D227A could be conjugated to two bispecific antibodies, BsAb (anti-MUC1 x anti-CD3) and BsAb (anti-MUC1 x anti-CD28), which in combination had greater enhancing effects than mSEA-D227A-conjugated anti-MUC1 mAb, and combination of unconjugated BsAbs. These findings indicate a utility of mSEA-D227A-conjugated antibodies for targeted cancer immunotherapy.

Amino Acid Substitution↗
PubMed2001

Combined use of adenosine and amrinone inhibits reperfusion injury of rat liver.

Although intraportal infusion of adenosine suppressed the oxidative stress caused by activated neutrophils and attenuated ischemia-reperfusion injury of canine liver, high doses of adenosine elicit systemic hypotension. The present work demonstrates that combined use of low doses of adenosine and amrinone, a phosphodiesterase inhibitor, strongly inhibited reperfusion injury of the liver without eliciting hypotension. After 45 min ischemia followed by 60 min reperfusion of rat liver, low doses of adenosine and amrinone were administrated intraportally, resulting in significantly increased hepatic levels of cGMP, cAMP, nitrite plus nitrate in plasma, and decreased alanine aminotransferase in plasma without changing hemodynamics. Thus, intraportal administration of low doses of adenosine and amrinone increased the cyclic nucleotides, thereby improved microcirculation and attenuated reperfusion injury of the liver.

Journal Article↗
PubMed2001

Influence of previous interferon therapy on recurrence after resection of hepatitis c virus-related hepatocellular carcinoma.

Interferon (IFN) therapy decreases the incidence of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV). One hundred and fifty-nine consecutive patients who underwent liver resection for HCV-related HCC were studied. In 17 (group 1) of the 159 patients, HCC was detected during or after IFN therapy. The incidences of recurrence after surgery in the group 1 patients and the other 142 patients (group 2) were compared. Eight patients had a complete response to IFN, 4 had a partial response, and 5 had no response. The proportion of patients without HCV viremia was significantly higher in the group 1 patients (P < 0.0001). The tumor-free survival rate was significantly higher in the group 1 patients (P = 0.0010). By multivariate analysis of various risk factors for recurrence, no previous IFN was a significant independent risk factor for recurrence (risk ratio = 6.336; 95%CI, 1.512 - 26.50). The patients with HCC who underwent IFN therapy previously are good candidates for liver resection because recurrence after the operation was rarely observed.

Aged↗
PubMed2001

Relationship of the microvascular type to the tumor size, arterialization and dedifferentiation of human hepatocellular carcinoma.

Unlike normal liver with the sinusoids, hepatocellular carcinomas (HCCs) possess capillaries. Whether these capillaries derive from the sinusoids remains unclear in human HCCs. This study aimed to examine sinusoidal capillarization in human HCCs and its relationship to the tumor size, arterialization and dedifferentiation. Thirty-eight HCCs with a diameter of 10 - 140 mm were pathologically and angiographically examined. By electron microscopy, the microvasculature of tumors was classified into sinusoidal, intermediate and capillary types, which were all negative, partially positive and all positive, respectively, for four parameters, i.e., endothelial defenestration, continuous basement membrane, lack of Kupffer cells, and lack of lipid-containing hepatic stellate cells. Well-, moderately and poorly differentiated HCCs displayed sinusoidal / intermediate / capillary types, intermediate / capillary types and only capillary type, respectively, suggesting the transition from the sinusoids to capillaries in well-differentiated (and probably moderately differentiated) HCCs. Furthermore, well-differentiated HCCs with a diameter of less than 30 mm often received preferential portal venous blood, while moderately and poorly differentiated ones were all supplied with arterial blood, indicating a relationship between dedifferentiation and arterialization. In contrast, the microvascular type displayed no significant relationship with tumor size or arterialization in well-differentiated HCCs. The present study has demonstrated that sinusoidal capillarization occurs in human well-differentiated HCCs and seems to be related to dedifferentiation of parenchymal tumor cells, but not to tumor size or arterialization.

Adult↗
PubMed2001

Virologic and biochemical changes and prognosis after liver resection for hepatitis B virus-related hepatocellular carcinoma.

BACKGROUND/AIMS: During the natural course of hepatitis B virus (HBV) infection, clearance of HB e antigen (HBeAg) and HB surface antigen (HBsAg) occurs with remission of liver disease. We investigated the effects of postoperative changes in virologic and biochemical parameters on the prognosis after liver resection for HBV-related hepatocellular carcinoma (HCC). METHODS: We investigated the relationship between postoperative changes in virologic and biochemical parameters and the incidence of intrahepatic recurrence and the outcome during a 3-year period following surgery in 30 HCC patients with HBsAg. RESULTS: The incidence of intrahepatic recurrence of HCC was significantly higher in patients with acute postoperative exacerbation of hepatitis (p = 0.0084), a sustained high serum concentration of HBV DNA (> or = 5.0 mEq/ml, p = 0.001), and sustained expression of HBsAg after surgery (p = 0.0421). A high serum concentration of HBV DNA was significantly associated with a shorter survival time (p = 0.0447) and the cause of death was recurrence of HCC. CONCLUSION: Patients with acute postoperative exacerbation of hepatitis, sustained HBsAg expression, and sustained high serum concentrations of HBV DNA after surgery may require more intensive postoperative monitoring for HCC recurrence.

Adult↗
PubMed2001

Treatment of adrenal metastases after hepatic resection of a hepatocellular carcinoma.

BACKGROUND: The adrenal gland is a common site of extrahepatic metastases from a hepatocellular carcinoma (HCC). However, treatment of adrenal metastases has not been well characterized. METHODS: Of 562 patients who underwent hepatic resection for a HCC, 91 developed extrahepatic metastases. We reviewed the medical records of 10 patients with adrenal metastases (9 males and 1 female; mean age 63 years at the time of hepatic resection). RESULTS: The mean diameter of the primary tumors was 5 cm, and all were located in the right lobe of the liver. The mean interval from hepatic resection to recurrence was 18 months. Seven patients underwent treatment of intrahepatic recurrence. To treat the adrenal metastases, surgical resection was performed in 4 patients, and transcatheter arterial embolization was performed in 1 patient. The patients treated had no other extrahepatic metastases. The mean diameter of the resected adrenal tumors was 6 cm. There was no hospital mortality. With surgical resection, 1 patient has been alive 63 months after recurrence. CONCLUSIONS: Adrenal metastases from a HCC were often large at the time of diagnosis. Since surgical resection was a safe procedure, and some patients could be alive for a long time, it should be performed whenever possible.

Adrenal Gland Neoplasms↗