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51.
Aim: Owing to carelessness of endoscopists, invasive procedures, such as biopsy, are sometimes carried out inadvertently in patients receiving antithrombotic therapy. The aim of the present study was to retrospectively evaluate the actual status of such careless mistakes and the efficacy of new safety measures. Methods: A questionnaire survey was conducted in 34 endoscopists at Toranomon Hospital about experiences of careless mistakes and experiences of anxiety before and after the procedure. ‘Anxiety before procedure’ was defined as the experience of discontinuing a given procedure because endoscopists remembered that the patient was receiving antithrombotic therapy, and ‘anxiety after procedure’ was defined as the experience of feeling anxious about the status of medication after the invasive procedure. A new measure was introduced at Health Management Center in August 2009. In this measure, endoscopists directly interview each patient about the status of medication just before examination, and attach forceps valves of one of two colors depending on the status of medication. A blue forceps valve is attached for patients undergoing antithrombotic therapy, and a conventional black forceps valve is attached for patients not undergoing antithrombotic therapy. Six months after introduction, a questionnaire survey was conducted in 10 endoscopists in this center. Results: Approximately half of endoscopists (18/34) experienced such careless mistakes. ‘Anxiety’ had been experienced by approximately 80%. After introduction, there was no report of careless mistakes and frequency of ‘anxiety’ evaluated by visual analog scale score decreased significantly. Conclusion: This new safety measure is expected to facilitate safer gastrointestinal endoscopy in patients receiving antithrombotic therapy.  相似文献   
52.
Summary The C-terminal R peptide of ecotropic murine leukemia virus (MLV) envelope protein (Env) negatively controls membrane fusion activity. The R peptide cleavage during virion maturation activates its fusogenicity and is required for viral entry. We analyzed fusogenicity and transduction efficiency of mutant Env proteins of ecotropic, amphotropic, polytropic, and xenotropic MLVs. As the result, we found that the hydrophobic amino acid residues around the R peptide cleavage site are important for membrane fusion inhibition by the R peptide. In addition, we found that Env complexes with R peptide-truncated and -containing Env proteins have lower fusogenicity and transduction efficiency than those with the R-peptide-truncated Env alone, suggesting that efficient R peptide cleavage is required for efficient MLV vector transduction. The role of R peptide cleavage in amphotropic, polytropic, and xenotropic MLV infection has not been investigated. We found in this study that the R peptide cleavage is required for amphotropic, xenotropic, and polytropic MLV vector transduction, like with ecotropic MLV. The R-peptide-truncated Env proteins of the xenotropic and polytropic MLVs, however, had much lower fusogenicity than those of the ecotropic and amphotropic MLVs. These results provide valuable information for construction of efficient MLV vectors and for understanding the retroviral entry mechanism.  相似文献   
53.
Esophagus - Talaporfin sodium photodynamic therapy (tPDT) is an effective salvage treatment for local failure after chemoradiotherapy for esophageal cancer. Repeated tPDT could also be indicated...  相似文献   
54.
A 69-year-old man was diagnosed as having idiopathic thrombocytopenic purpura (ITP) in April 2000, and treated with prednisolone (PSL) without effect. Splenectomy performed in June 2000 had only a transient and marginal influence on his platelet count. Two months later, he developed autoimmune hemolytic anemia (AIHA) without Coombs test positivity, and his diagnosis was changed to Coombs-negative Evans syndrome. Treatment with PSL led to recovery of his hemoglobin level, but not his platelet count. Although the mechanism responsible for development of AIHA after splenectomy in this patient with ITP remains unknown, close observation is required for any association with other autoimmune diseases such as SLE.  相似文献   
55.
Gastric inhibitory polypeptide (GIP) is a 42-amino acid hormone that stimulates insulin secretion in the presence of glucose. Complementary DNA clones encoding human GIP were isolated from a library prepared with RNA from duodenum. The predicted amino acid sequence indicates that GIP is derived by proteolytic processing of a 153-residue precursor, preproGIP. The GIP moiety is flanked by polypeptide segments of 51 and 60 amino acids at its NH2 and COOH termini, respectively. The former includes a signal peptide of about 21 residues and an NH2-terminal propeptide of 30 amino acids. GIP is released from the precursor by processing at single arginine residues. There is a region of nine amino acids in the COOH-terminal propeptide of the GIP precursor that has partial homology with a portion of chromogranin A as well as pancreastatin.  相似文献   
56.
The prognosis of patients with primary mediastinal large B-cell lymphoma has improved over recent years. However, the optimal treatment strategy including the role of radiotherapy remains unknown. We retrospectively analyzed the clinical outcomes of 345 patients with newly diagnosed primary mediastinal large B-cell lymphoma in Japan. With a median follow up of 48 months, the overall survival at four years for patients treated with R-CHOP (n=187), CHOP (n=44), DA-EPOCH-R (n=9), 2nd- or 3rd-generation regimens, and chemotherapy followed by autologous stem cell transplantation were 90%, 67%, 100%, 91% and 92%, respectively. Focusing on patients treated with R-CHOP, a higher International Prognostic Index score and the presence of pleural or pericardial effusion were identified as adverse prognostic factors for overall survival in patients treated with R-CHOP without consolidative radiotherapy (IPI: hazard ratio 4.23, 95% confidence interval 1.48–12.13, P=0.007; effusion: hazard ratio 4.93, 95% confidence interval 1.37–17.69, P=0.015). Combined with the International Prognostic Index score and the presence of pleural or pericardial effusion for the stratification of patients treated with R-CHOP without radiotherapy, patients with lower International Prognostic Index score and the absence of effusion comprised approximately one-half of these patients and could be identified as curable patients (95% overall survival at 4 years). The DA-EPOCH-R regimen might overcome the effect of these adverse prognostic factors. Our simple indicators of International Prognostic Index score and the presence of pleural or pericardial effusion could stratify patients with primary mediastinal large B-cell lymphoma and help guide selection of treatment.  相似文献   
57.
58.
MicroRNAs (miRNAs) fine‐tune cellular signaling by regulating expression of signaling proteins, and aberrant expression of miRNAs is observed in many cancers. The tyrosine kinase c‐Src is upregulated in various human cancers, but the molecular mechanisms underlying c‐Src‐mediated tumor progression remain unclear. In previous investigations of miRNA‐mediated control of c‐Src‐related oncogenic pathways, we identified miRNAs that were downregulated in association with c‐Src transformation and uncovered the signaling networks by predicting their target genes, which might act cooperatively to control tumor progression. Here, to further elucidate the process of cell transformation driven by c‐Src, we analyzed the expression profiles of miRNAs in a doxycycline‐inducible Src expression system. We found that miRNA (miR)‐129‐1‐3p was downregulated in the early phase of c‐Src‐induced cell transformation, and that reexpression of miR‐129‐1‐3p disrupted c‐Src‐induced cell transformation. In addition, miR‐129‐1‐3p downregulation was tightly associated with tumor progression in human colon cancer cells/tissues. Expression of miR‐129‐1‐3p in human colon cancer cells caused morphological changes and suppressed tumor growth, cell adhesion, and invasion. We also identified c‐Src and its critical substrate Fer, and c‐Yes, a member of the Src family of kinases, as novel targets of miR‐129‐1‐3p. Furthermore, we found that miR‐129‐1‐3p‐mediated regulation of c‐Src/Fer and c‐Yes is important for controlling cell adhesion and invasion. Downregulation of miR‐129‐1‐3p by early activation of c‐Src increases expression of these target genes and synergistically promotes c‐Src‐related oncogenic signaling. Thus, c‐Src‐miR‐129‐1‐3p circuits serve as critical triggers for tumor progression in many human cancers that harbor upregulation of c‐Src.  相似文献   
59.

Background

Locomotive syndrome (LS) includes disorders of the musculoskeletal system and is a high-risk condition that requires nursing care. We included an examination of locomotive function in specific health checkups to investigate the relationship between LS risk and the muscle strengths. The purpose of this study was to determine the distribution of LS and the relationship between LS and metabolic syndrome (MetS).

Methods

Among 2695 participants who undertook a specific health checkup, 790 received a locomotive examination (302 men and 488 women; mean age, 65.9 years). Data for MetS components were measured in the specific health checkup. Data about the locomotive examination were obtained from five tests: the two-step test, stand-up test, 25-question Geriatric Locomotive Function Scale, and measurement of lower limb muscular strength and grip strength.

Results

The MetS components did not differ according to LS risk level in men. In women, body weight, body mass index, and abdominal circumference were significantly lower in the non-LS group than in the LS risk level 1 or 2 groups. The ratio of lower limb muscular strength to body weight differed significantly between all risk groups in men and women. In women, lower limb muscular strength was significantly higher in those at risk of both LS and MetS (double-risk group) than in the LS-only group. In women, the ratio of lower limb muscular strength to body weight was significantly lower in the double-risk group than in the LS-only group.

Conclusions

Adding a locomotive examination to the specific health checkup may be useful for identifying people at risk of LS or MetS. The prevalence rates of LS and MetS correlate positively in women. The ratio of lower limb muscular strength to body weight might be a better index of locomotor dysfunction than lower limb muscular strength alone.  相似文献   
60.
Serious valve-related complications that occur in patients with prosthetic valves have been discussed. The emergency physician's role primarily is to recognize the high probability that one of these serious complications exists and hospitalize the patient so that rapid definitive diagnoses and therapeutic decisions are not delayed.  相似文献   
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