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41.

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Objective

To assess the accuracy of available tools to predict LNI and to develop a novel model for men diagnosed via MRI-targeted biopsies.

Design, setting, and participants

A total of 497 patients diagnosed via MRI-targeted biopsies and treated with RP and extended pelvic lymph node dissection (ePLND) at five institutions were retrospectively identified.

Outcome measurements and statistical analyses

Three available models predicting LNI were evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analyses. A nomogram predicting LNI was developed and internally validated.

Results and limitations

Overall, 62 patients (12.5%) had LNI. The median number of nodes removed was 15. The AUC for the Briganti 2012, Briganti 2017, and MSKCC nomograms was 82%, 82%, and 81%, respectively, and their calibration characteristics were suboptimal. A model including PSA, clinical stage and maximum diameter of the index lesion on multiparametric MRI (mpMRI), grade group on targeted biopsy, and the presence of clinically significant PCa on concomitant systematic biopsy had an AUC of 86% and represented the basis for a coefficient-based nomogram. This tool exhibited a higher AUC and higher net benefit compared to available models developed using standard biopsies. Using a cutoff of 7%, 244 ePLNDs (57%) would be spared and a lower number of LNIs would be missed compared to available nomograms (1.6% vs 4.6% vs 4.5% vs 4.2% for the new nomogram vs Briganti 2012 vs Briganti 2017 vs MSKCC).

Conclusions

Available models predicting LNI are characterized by suboptimal accuracy and clinical net benefit for patients diagnosed via MRI-targeted biopsies. A novel nomogram including mpMRI and MRI-targeted biopsy data should be used to identify candidates for ePLND in this setting.

Patient summary

We developed the first nomogram to predict lymph node invasion (LNI) in prostate cancer patients diagnosed via magnetic resonance imaging-targeted biopsy undergoing radical prostatectomy. Adoption of this model to identify candidates for extended pelvic lymph node dissection could avoid up to 60% of these procedures at the cost of missing only 1.6% patients with LNI.  相似文献   
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43.
Postoperative complications(PC) are a basic health outcome, but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it performs. Most studies that have assessed the cost of PC suffer from poor quality and a lack of transparency and consistency. The payment system in place often rewards the volume of services provided rather than the quality of patients' clinical outcomes. Without a thorough registration of PC, the economic costs involved cannot be determined. An accurate, reliable appraisal would help identify areas for investment in order to reduce the incidence of PC,improve surgical results, and bring down the economic costs. This article describes how to quantify and classify PC using the Clavien-Dindo classification and the comprehensive complication index, discusses the perspectives from which economic evaluations are performed and the minimum postoperative follow-up established, and makes various recommendations. The availability of accurate and impartially audited data on PC will help reduce their incidence and bring down costs. Patients, the health authorities, and society as a whole are sure to benefit.  相似文献   
44.
This paper describes a study to capture the key roles and activities of nephrology nurses across different countries in Europe. The concept of the study and the need to clarify the activities of the nephrology nurse arose as part of a larger study to develop the European Practice Database (EPD) (1). The Research Board (EDTNA/ERCA) needed to identify key questions that would detect significant differences in the role and responsibilities of nephrology nurses in different countries and monitor the evolution over time of nephrology nursing practice in Europe. It was therefore appropriate to devise a separate small study to generate evidence based questions for the EPD and confirm the reliability and usefulness of the information captured.  相似文献   
45.
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease.  相似文献   
46.
47.
OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility.  相似文献   
48.
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements.  相似文献   
49.
Abstract  The discipline of nursing is still struggling with the differences that need to be clearly defined between the notions of care and nursing care. To be able to clarify this distinction, agreement must first be reached on the meaning of care itself. The present article proposes a conception of care in light of the philosophy of Emmanuel Levinas (1906–1995). This philosopher's thought throws considerable light on the ontology of care, thanks especially to his focus on the deeper implications of human encounter. A profound sense of responsibility towards the other enables Levinas to bring out such dimensions of the concept of care as the relation involved, the feeling of affection, and the interventions. We examine here what these entail regarding nursing care.  相似文献   
50.
BACKGROUND: Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. OBJECTIVES: To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. MATERIAL AND METHODS: One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. RESULTS: Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. CONCLUSIONS: These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.  相似文献   
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