CODE SEC.XI BASED ON FAILURE PROBABILITY

ABSTRACT Based on the faihre probability, the flaw acceptaao~ standard of ASME Code Sec. XI is examined with some concerns weather tbe faihre l~vbabflity is unif~in for flaws with various aspect ratios and failure frcquoneies are small enough. In this paper, the results of lreliminmy case studies are deseff0ed on liae failure probability of n~etor pressure vessels (RPVs) with a surface flaw specified in Scc. XI. PFM code PASCAL was used for case studies. A PTS (Pressurized Thermal Shock) Iransient prescn'bcd by NRC2EPRI ITS Benchmark Study was used as an applied load. Analysis results showcd that the conditional failure probability of a RPV wilh ~m initial flaw of acceptable depth depends on the aspect mlio. h case flaw' shapes ~ze close to semi-circular, the failme probability are higher than that of the eases aspect ration are less than 0.6 by one order of magnitude due to the diffczeace of fracture behavior at the surface point. A case study for determining the acceptable flaws based on failure probability was also eanied on

A prospective study to evaluate a new dental management protocol before hematopoietic stem cell transplantation

Pre-hematopoietic stem cell transplantation (HSCT) dental treatment is essential to prevent serious infections from oral sources during immunosuppression, in patients who undergo HSCT therapy. This study was planned to establish a dental management protocol for such patients. Forty-one patients scheduled for HSCT to treat hematological malignancies were consecutively enrolled in the prospective trial. The dental status of all patients was evaluated by clinical and radiographic examination at a median of 47 days before the commencement of HSCT therapy. Thirty-six patients had one or more dental diseases; the remaining five had none. Caries was found in 26 patients, apical periodontitis in 19, marginal periodontitis in 24 and a partially erupted third molar in 11. Our policy is to preserve patients\u27 teeth whenever possible, and therefore minimal dental intervention was planned. Treatment was completed for all 36 patients with dental pathologies, before the conditioning regimen began. All patients received the scheduled HSCT therapy without alteration, interruption or delay, and did not show any signs or symptoms associated with odontogenic infection while they were immunosuppressed. This protocol, therefore, appears to be appropriate for the pre-HSCT dental treatment of patients with hematological diseases

Delay in referral of oropharyngeal squamous cell carcinoma to secondary care correlates with a more advanced stage at presentation, and is associated with poorer survival

Squamous carcinoma of the oropharynx presents with symptoms common to many benign diseases, and this can cause delay in referral to secondary care. We investigate delay in referral, defining this as the time from symptom-onset to date of general practitioners referral letter to secondary care, and the effect of that delay, using a retrospective case notes based study of patients presenting at our institution with oropharyngeal squamous carcinoma between 1995 and 2005. Using correlation analysis and ordinal regression, we examined the relationship between increased referral delay from primary care, clinical stage at presentation, and survival. Increasing time from symptom onset to referral to secondary care was positively correlated with more advanced disease stage at presentation (rs=+0.346, P=0.004). This was confirmed with ordinal regression modelling (delay estimate=0.045, P=0.042). Patients with delay of less than 6 weeks had significantly improved survival compared to those with a delay of greater than 6 weeks (P=0.032). For every 1 week of delay in referral, we estimate that the stage of presentation will progress by 0.045 of ‘a stage'

Diagnostic aids in the screening of oral cancer

The World Health Organization has clearly indentified prevention and early detection as major objectives in the control of the oral cancer burden worldwide. At the present time, screening of oral cancer and its pre-invasive intra-epithelial stages, as well as its early detection, is still largely based on visual examination of the mouth. There is strong available evidence to suggest that visual inspection of the oral mucosa is effective in reducing mortality from oral cancer in individuals exposed to risk factors. Simple visual examination, however, is well known to be limited by subjective interpretation and by the potential, albeit rare, occurrence of dysplasia and early OSCC within areas of normal-looking oral mucosa. As a consequence, adjunctive techniques have been suggested to increase our ability to differentiate between benign abnormalities and dysplastic/malignant changes as well as to identify areas of dysplasia/early OSCC that are not visible to naked eye. These include the use of toluidine blue, brush biopsy, chemiluminescence and tissue autofluorescence. The present paper reviews the evidence supporting the efficacy of the aforementioned techniques in improving the identification of dysplastic/malignant changes of the oral mucosa. We conclude that available studies have shown promising results, but strong evidence to support the use of oral cancer diagnostic aids is still lacking. Further research with clear objectives, well-defined population cohorts, and sound methodology is strongly required

Temporomandibular joint dysfunction and orthognathic surgery: a retrospective study

<p>Abstract</p> <p>Background</p> <p>Relations between maxillo-mandibular deformities and TMJ disorders have been the object of different studies in medical literature and there are various opinions concerning the alteration of TMJ dysfunction after orthognathic surgery. The purpose of the present study was to evaluate TMJ disorders changes before and after orthognathic surgery, and to assess the risk of creating new TMJ symptoms on asymptomatic patients.</p> <p>Methods</p> <p>A questionnaire was sent to 176 patients operated at the Maxillo-Facial Service of the Lille's 2 Universitary Hospital Center (Chairman Pr Joël Ferri) from 01.01.2006 to 01.01.2008. 57 patients (35 females and 22 males), age range from 16 to 65 years old, filled the questionnaire. The prevalence and the results on pain, sounds, clicking, joint locking, limited mouth opening, and tenseness were evaluated comparing different subgroups of patients.</p> <p>Results</p> <p>TMJ symptoms were significantly reduced after treatment for patients with pre-operative symptoms. The overall subjective treatment outcome was: improvement for 80.0% of patients, no change for 16.4% of patients, and an increase of symptoms for 3.6% of them. Thus, most patients were very satisfied with the results. However the appearance of new onset of TMJ symptoms is common. There was no statistical difference in the prevalence of preoperative TMJ symptoms and on postoperative results in class II compared to class III patients.</p> <p>Conclusions</p> <p>These observations demonstrate that: there is a high prevalence of TMJ disorders in dysgnathic patients; most of patients with preoperative TMJ signs and symptoms can improve TMJ dysfunction and pain levels can be reduced by orthognathic treatment; a percentage of dysgnathic patients who were preoperatively asymptomatic can develop TMJ disorders after surgery but this risk is low.</p

Suppressor of cytokine signaling 3 (SOCS3) is not an independent biomarker of colorectal adenoma risk

<p>Abstract</p> <p>Background</p> <p>Inflammation and its associated pathologies are increasingly suggested as risk factors for colorectal cancer (CRC) development. Previous research from our group has shown that increased levels of circulating, pro-inflammatory cytokines IL-6 and TNFα promote colorectal adenoma risk. Emerging data in mice and humans suggest that Suppressor of Cytokine Signaling 3 (SOCS3) may act as a tumor suppressor in the intestine, and decreased SOCS3 expression may promote CRC. As SOCS3 has been shown to inhibit the actions of IL-6 and TNFα in the intestine, we hypothesized that decreased SOCS3 expression in normal mucosa may predispose to adenomas and thus increase risk for CRC.</p> <p>Findings</p> <p>We examined SOCS3 mRNA levels in normal mucosa biopsies of 322 screening colonoscopy patients (93 with adenoma and 229 without adenoma) using real-time qRT-PCR. Logistic regression analysis was used to generate odds ratios (OR) and 95% confidence intervals to determine if low SOCS3 expression was associated with adenoma status. Median SOCS3 values did not differ between patients with or without adenoma. Logistic regression analysis showed no association (unadjusted or adjusted for age and sex) between SOCS3 and colorectal adenomas.</p> <p>Conclusions</p> <p>Low SOCS3 mRNA expression is not an independent biomarker of colorectal adenoma risk in the normal mucosa. SOCS3 silencing likely occurs later in CRC progression.</p

Selective accumulation of ALA-induced PpIX and photodynamic effect in chemically induced hepatocellular carcinoma

浜松医科大学学位論文　医博論第397号(平成１７年３月１０日

Strong neuroprotection with a novel platinum nanoparticle against ischemic stroke- andtissue plasminogen activator-related brain damages in mice

Reactive oxygen species (ROS) are major exacerbation factor in acute ischemic stroke, and thrombolytic agent tissue plasminogen activator (tPA) may worsen motor function and cerebral infarcts. The platinum nanoparticle (nPt) is a novel ROS scavenger, and thus we examined the clinical and neuroprotective effects of nPt in ischemic mouse brains. Mice were subjected to transient middle cerebral artery occlusion (tMCAO) for 60 min and divided into the following four groups by intravenous administration upon reperfusion, vehicle, tPA, tPA + nPt, and nPt. At 48 h after tMCAO, motor function, infarct volume, immunohistochemical analyses of neurovascular unit (NVU), in vivo imaging of matrix metalloproteinase (MMP), and zymography for MMP-9 activity were examined. Superoxide anion generation at 2 h after tMCAO was also examined with hydroethidine (HEt). As a result, administration of tPA deteriorated the motor function and infarct volume as compared to vehicle. In vivo optical imaging of MMP showed strong fluorescent signals in affected regions of tMCAO groups. Immunohistochemical analyses revealed that tMCAO resulted in a minimal decrease of NAGO and occludin, but a great decrease of collagen IV and a remarkable increase of MMP-9. HEt stain showed increased ROS generation by tMCAO. All these results became pronounced with tPA administration, and were greatly reduced by nPt. The present study demonstrates that nPt treatment ameliorates neurological function and brain damage in acute cerebral infarction with neuroprotective effect on NVU and inactivation of MMP-9. The strong reduction of ROS production by nPt could account for these remarkable neurological and neuroprotective effects against ischemic stroke

Ki-67 expression predicts locoregional recurrence in stage I oral tongue carcinoma

Oral tongue squamous cell carcinoma (OTSCC) is an aggressive cancer associated with poor prognosis. Methods for determining the aggressiveness of OTSCC from analysis of the primary tumour specimen are thus highly desirable. We investigated whether genomic instability and proliferative activity (by means of Ki-67 activity) could be of clinical use for prediction of locoregional recurrence in 76 pretreatment OTSCC paraffin samples (stage I, n=22; stage II, n=33; stage III, n=8; stage IV, n=13). Eleven surgical tumour specimens were also analysed for remnants of proliferative activity after preoperative radiotherapy. Ninety-seven percent of cases (n=72) were characterised as being aneuploid as measured by means of image cytometry. Preoperative radiotherapy (50–68 Gy) resulted in significant reduction of proliferative activity in all patients for which post-treatment biopsies were available (P-value=0.001). Proliferative activity was not associated with response to radiation in stage II patients. However, we report a significant correlation between high proliferation rates and locoregional recurrences in stage I OTSCC patients (P-value=0.028). High-proliferative activity is thus related to an elevated risk of recurrence after surgery alone. We therefore conclude that Ki-67 expression level is a potentially useful clinical marker for predicting recurrence in surgically treated stage I OTSCC