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971.

Objectives

Phenylbis(acyl) phosphine oxide (BAPO) and diphenyl(acyl) phosphine oxide (TPO) are alternative photoinitiators to camphorquinone (CQ) in dental resinous materials. Aim of this study was to investigate their cytotoxic/genotoxic potential in human oral keratinocytes (OKF6/Tert2) and Chinese hamster lung fibroblasts (V79) in comparison to CQ.

Methods

Cells were exposed to different concentrations of BAPO and TPO (1–50 μM). Cytotoxicity was evaluated using H33342 and MTT assay, cell proliferation by BrdU proliferation assay and microscopy. Effects on cellular redox homeostasis were assessed by detecting intracellular levels of reactive oxygen/nitrogen species (ROS/RNS) using the DCFH2 assay and by quantification of mRNA expression of oxidatively regulated, cyto-protective enzymes. Genotoxic potential was determined by use of micronucleus (MN) assay.

Results

BAPO and TPO induced a concentration-dependent decrease of cell number. BAPO and TPO showed 50- to 250-fold higher cytotoxicity than CQ. In contrast to CQ, both photoinitiators revealed no increase of intracellular ROS/RNS. However, BAPO (10 μM) at least significantly induced mRNA-expression of redox-regulated proteins after 24 h similar to 2.5 mM CQ. Additionally, BAPO significantly raised the number of micronuclei, but only in V79 cells (10 μM: 12 ± 1, 2.5 mM CQ: 15 ± 1, medium control: 6 ± 3). However, it also significantly decreased proliferation of these cells (10 μM BAPO: 19.8% ± 7.3% compared to controls).

Significance

BAPO and TPO revealed concentration-dependent cytotoxic effects in human oral keratinocytes and V79 cells. However, in contrast to CQ, no generation of intracellular ROS/RNS was found. Only BAPO induced genotoxicity in V79 cells.  相似文献   
972.
The purpose of the study was to evaluate the efficacy of conservative surgical treatment of medication related osteonecrosis of the jaw (MRONJ) in patients affected by osteoporosis and exposed to oral bisphosphonates (BPs).Subjects diagnosed with MRONJ and osteoporosis under oral BPs that had undergone conservative surgery and had at least 24 months follow-up were included. All patients received medical-antibiotic therapy and then underwent conservative surgical treatment consisting of sequestrectomy, soft tissue debridement and bone curettage with limited or no extension.A total of 53 patients, mean age of 71.9 ± 10.2 years (range 41–87), were enrolled. Two years after conservative surgical therapy 45 patients (91.8%) showed complete healing. The presence of rheumatoid arthritis (p = 0.003) and a more severe initial MRONJ stage (p = 0.023) were associated with a negative surgical outcome while the presence of bone sequestrum was strongly associated with a positive outcome (p = 0.036).Conservative surgical treatment of MRONJ lesions in patients affected by osteoporosis and receiving only oral BPs may represent a valid therapeutic approach determining a high number of complete healing cases. Conservative surgery should be encouraged at early MRONJ stages and after medical therapy failure.  相似文献   
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976.

Background

Abdominal aortic aneurysm (AAA) is a frequent cause of death among elderly. Patients affected by lower extremity peripheral arterial disease (LE-PAD) seem to be particularly at high risk for AAA. We aimed this study at assessing the prevalence and the clinical predictors of the presence of AAA in a homogeneous cohort of LE-PAD patients affected by intermittent claudication.

Methods

We performed an abdominal ultrasound in 213 consecutive patients with documented LE-PAD (ankle/brachial index ≤0.90) attending our outpatient clinic for intermittent claudication. For each patient we registered cardiovascular risk factors and comorbidities, and measured neutrophil count.

Results

The ultrasound was inconclusive in 3 patients (1.4%), thus 210 patients (169 males, 41 females, mean age 65.9 ± 9.8 yr) entered the study. Overall, AAA was present in 19 patients (9.0%), with a not significant higher prevalence in men than in women (10.1% vs 4.9%, p = 0.300). Patients with AAA were older (71.2 ± 7.0 vs 65.4 ± 9.9 years, p = 0.015), were more likely to have hypertension (94.7% vs 71.2%, p = 0.027), and greater neutrophil count (5.5 [4.5 – 6.2] vs 4.1 [3.2 – 5.5] x103/μL, p = 0.010). Importantly, the c-statistic for neutrophil count (0.73, 95% CI 0.60 – 0.86, p =0.010) was higher than that for age (0.67, CI 0.56–0.78, p = 0.017). The prevalence of AAA in claudicant patients with a neutrophil count ≥ 5.1 x103/μL (cut-off identified at ROC analysis) was as high as 29.0%.

Conclusions

Prevalence of AAA in claudicant patients is much higher than that reported in the general population. Ultrasound screening should be considered in these patients, especially in those with an elevated neutrophil count.
  相似文献   
977.
ObjectivesComputer-aided joint space analysis (CAJSA) is a recently developed, semi-automated tool to aid in the measurement of joint space margins based on hand radiographs. The objective of this study is to verify the potential effect of hand rotation during X-ray imaging on the measurement of joint space width using CAJSA and to evaluate the reproducibility of the CAJSA technique in healthy subjects and in patients with rheumatoid arthritis.MethodsAll joint space distance (JSD) measurements were performed using CAJSA-technology at the metacarpophalangeal articulation based on conventional and digital hand radiographs.ResultsI. Hand rotation showed an effect on the reproducibility with CV ranging between 0.39% (angulation 1°) and 1.66% (angulation 19°). II. Regarding the overall reproducibility of the CAJSA method, the intra-radiograph reproducibility of JSD was calculated with CV = 0.54% for conventional images and CV = 0.38% for digital images. The inter-radiograph reproducibility error was observed with CV = 0.66% (conventional images) and CV = 0.63% (digital images). III. The study revealed a reproducibility for CAJSA measurements in RA ranging between 0.37% (JSD-MCP ring finger; van der Heijde-modification of the Sharp method Score 1) to 1.37% (JSD-MCP index finger; van der Heijde-modification of the Sharp method Score 3).ConclusionCAJSA measures JSD at the metacarpophalangeal articulation with high reproducibility in healthy subjects and in patients with differing stages of rheumatoid arthritis. Additional findings show that hand rotation during X-ray imaging has an impact on the CAJSA measurements; thus avoiding acquisition of hand radiographs with a rotation error of more than 15 degrees can be recommended.  相似文献   
978.
Accurate and readily available systems for risk stratification and a wide array of antithrombotic agents, on top of classical anti-ischemic drugs, provide the noninvasive cardiologist admitting the patient in the CCU with an effective and reliable armamentarium for the safe management of most patients with ACS. From the interventionalist’s perspective, the immediate knowledge of the coronary anatomy yields the most valuable information to address the most appropriate treatment. The sooner angiography is performed the higher the benefit for patients at moderate to high risk, but if performed by expert teams and with the correct use of modern drugs and devices, the invasive approach has the potential to reduce costs and length of hospital stay also in low-risk patients. Although still some reluctance remains to equalize treatment strategies for patients with STEMI to those with NSTEMI, such differences will likely disappear in the near future with upcoming new evidence. Cardiac surgery may represent a life-saving alternative for patients presenting with NSTEMI evolving in cardiogenic shock or with mechanical complications, or in patients unsuitable for PCI or with failed PCI attempts. In stabilized conditions after the treatment of the culprit lesion, patients with severe multivessel disease may benefit from cardiac surgery to complete myocardial revascularization. Indications for CABG in this setting should be evaluated in the context of a local “heart team” or through prespecified protocols in centers without cardiac surgery on site.  相似文献   
979.

Objective

Classification criteria for systemic sclerosis (SSc; scleroderma) are being updated. Our objective was to select a set of items potentially useful for the classification of SSc using consensus procedures, including the Delphi and nominal group techniques (NGT).

Methods

Items were identified through 2 independent consensus exercises performed by the Scleroderma Clinical Trials Consortium and the European League Against Rheumatism Scleroderma Trials and Research Group. The first‐round items from both exercises were collated and redundancies were removed, leaving 168 items. A 3‐round Delphi exercise was performed using a 1–9 scale (where 1 = completely inappropriate and 9 = completely appropriate) and a consensus meeting using NGT was conducted. During the last Delphi round, the items were ranked on a 1–10 scale.

Results

In round 1, 106 experts rated the 168 items. Those with a median score of <4 were removed, resulting in a list of 102 items. In round 2, the items were again rated for appropriateness and subjected to a consensus meeting using NGT by European and North American SSc experts (n = 16), resulting in 23 items. In round 3, SSc experts (n = 26) then individually scored each of the 23 items in a last Delphi round using an appropriateness score ( 1 - 9 ) and ranking their 10 most appropriate items for the classification of SSc. Presence of skin thickening, SSc‐specific autoantibodies, abnormal nailfold capillary pattern, and Raynaud's phenomenon ranked highest in the final list that also included items indicating internal organ involvement.

Conclusion

The Delphi exercise and NGT resulted in a set of 23 items for the classification of SSc that will be assessed for their discriminative properties in a prospective study.  相似文献   
980.
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