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101.
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Oxidation is a common degradation pathway that affects therapeutic proteins and peptides during production, purification, formulation, transportation, storage and handling of solid and liquid preparations. In the present work we review the scientific literature about structural and biological consequences of protein/peptide oxidation. Representative examples are discussed of specific products whose oxidation has been recently studied, including monoclonal antibodies, calcitonin, granulocyte colony-stimulating factor, growth hormone, insulin, interferon alpha and beta, oxytocin and parathyroid hormone. These examples illustrate that oxidation often leads to modifications of higher-order structures, including aggregate induction, and can generate products that are pharmacokinetically different, biologically less active and/or potentially more immunogenic than their native counterpart. It is therefore crucially important during the pharmaceutical development of therapeutic proteins and peptides to comprehensively characterize oxidation products and evaluate the impact of oxidation-induced structural modifications on the biological properties of the drug.  相似文献   
103.
Since its introduction, total joint arthroplasty (TJA) has improved the quality of life of patients with degenerative joint disorders. In the last decades, a number of conventional and biological disease-modifying antirheumatic drugs have become available for the treatment of patients with inflammatory rheumatic diseases (IRD), leading to a reduction in the need to undergo TJA. However, TJA is still frequently performed in IRD patients. Both rheumatologists and orthopedics should be aware that patients with IRD have a peculiar perioperative risk profile due to disease-related, patient-related, and surgery-related risk factors. On the basis of current evidence, TJA is a safe procedure for IRD patients as long as an accurate risk stratification and a multidisciplinary approach are applied. We here describe the current strategies for an appropriate surgical management of osteoarthritis in IRD patients and the fascinating opening perspectives that surgeons and clinicians may expect in the future.  相似文献   
104.

Purpose

Partial nephrectomy (PN) is standard for small renal masses, improving renal function by preserving renal parenchyma compared with radical nephrectomy. Recent work demonstrated that postoperative surgeon assessment of volume preservation (SAVP) and 3D imaging measurements agree and correlate with postoperative function. We hypothesize preoperative assessment of volume preservation (PAVP) with PN based on preoperative imaging will reliably indicate postoperative renal function.

Materials and Methods

Data were collected from 336 patients undergoing PN for suspected renal cancer by 40 surgeons at 12 centers in Europe and the United States within the Surface-Intermediate-Base International Consortium. Surgeons recorded PAVP and SAVP for individual patients; pre- and postoperative glomerular filtration rate (GFR) was estimated by Chronic Kidney Disease Epidemiology Collaboration equations. Correlations between PAVP, SAVP, and postoperative GFR were assessed with linear regression models. Bland–Altman analysis was used to assess agreement between PAVP and SAVP with a significant cutoff of 5%.

Results

Median PAVP was 90% (interquartile range [IQR] 85%–100%) and SAVP was 90% (IQR: 80%–94%). PAVP and SAVP were moderately correlated (R2?=?0.67, P < 0.0001) and deemed “interchangeable” by Bland–Altman analysis at a 5% acceptable rate of difference (95% CI: ?5.4, ?3.1). Median postoperative GFR was 77.3 (IQR: 56.2, 92.0). Both PAVP (R2?=?0.82, P < 0.0001) and SAVP (R2?=?0.83, P < 0.0001) were correlated with postoperative GFR. Multivariable models utilizing volume-adjusted GFR based on PAVP or SAVP significantly and similarly predicted postoperative GFR (R2?=?0.72 for each).

Conclusion

Renal function is closely linked to the amount of parenchymal volume preservation, whether estimated prior to surgery (PAVP) or afterward (SAVP). PAVP provides reasonably accurate information for decision-making in patients considering PN.  相似文献   
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Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2 mm from both applicators tips, the maximum temperature increase is approximately 60 °C downward from the tips, while it increases of about 40 °C and 30 °C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91?±?0.09 vs. 0.95 cm3). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.  相似文献   
109.

Background and purpose

Placement of flow-diverters across the ostia of major ICA branches carries a risk of arterial occlusion. We determined the rate of occlusion of the supraclinoid ICA branches and the related symptoms, following coverage with flow-diverters.

Materials and methods

A systematic search was performed in PubMed, MEDLINE, and EMBASE. We selected studies reporting treatments with flow-diverters in which the device was placed across the ostium of the OphtA, PcomA, or AchorA. Random-effects meta-analysis was used to pool the following outcomes: rate of arterial occlusion, diminished flow, incidence of related symptoms, factors associated with arterial occlusion.

Result

Twenty-one studies evaluating 1152 supraclinoid ICA branches were included in the meta-analysis. The incidence of OphtA occlusion and associated symptoms was 5.9% (95 CI%?=?3.1–8.6%) (incidence rate?=?6% per patient-year), and 0.8% (95% CI?=?0.1–1.4%) (incidence rate?=?0.8% per patient-year), respectively. Although asymptomatic in all cases, PcomA showed a higher occlusion rate (20.7%, 95% CI?=?8.9–32.4%) (incidence rate?=?19.5% per patient-year). AchorA was occluded in 1% (95% CI?=?0.3–2.4%) of cases, with approximately 1% (95% CI?=?0.4–2.3%) of transient neurological symptoms (incidence rate?=?0.96% per patient-year). There was a trend toward higher odds of arterial patency among arteries arising from the aneurysm (OR?=?2.94, P?=?0.06). Demographic factors and multiple stents were not associated with higher risk of arterial impairment. Adequate collateral circulation was reported in 94.5% of patients with arterial occlusion.

Conclusions

During aneurysm treatment, the ostium of the supraclinoid ICA branches can be covered with flow-diverter devices with low rates of neurological symptoms related to arterial occlusion.  相似文献   
110.

Introduction

The objective of this study was to present the outcomes of moderately hypofractionated helical intensity-modulated radiation therapy (HT) with/without simultaneous integrated boost (SIB) on fluorodeoxyglucose-positron emission tomography (FDG-PET) positive areas (gross tumor volume [GTV]-PET) for patients with progressive malignant pleural mesothelioma (MPM) after previous treatments.

Methods and Materials

From May 2006 to April 2014, 51 patients with a median age of 68.8 years (range, 38.6-82 years) were treated. There were 41 men and 10 women; 43 epithelioid MPM and 8 sarcomatoid, involving the left pleura in 25 patients and the right pleura in 26 patients. The initial stage was: I, 11 patients; II, 14 patients; III, 17 patients; and IV, 9 patients. Chemotherapy was prescribed for 46 patients, for 6 cycles (range, 0-18 cycles). Eighteen patients had pleurectomy/decortication, and 33 had talc pleurodesis. FDG-PET was used for target identification. A median dose of 56 Gy/25 fractions was prescribed to the involved pleura, and SIB to 62.5 Gy to GTV-PET was added in 38 patients.

Results

The median survival from diagnosis was 25.8 months (range, 8.4-99.0 months). One patient, treated with SIB, was alive at the October 2017 follow-up. Two cases of grade 5 radiation pneumonitis were registered. A GTV-PET ≤ 205 cc was predictive of late ≥ grade 2 lung toxicity, but also of better survival in stage III and IV disease: 5.9 versus 11.7 months (P = .04). A GTV-PET ≥ 473 cc was predictive of early death (P = .001).

Conclusions

Moderately hypofractionated, FDG-PET guided salvage HT in patients with progressive MPM after previous treatments showed acceptable toxicity and outcome results similar to adjuvant radiotherapy after pleurectomy/decortication, suggesting that the delay of radiotherapy is not detrimental to survival, and has the associated benefit of postponing inherent toxicity.  相似文献   
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