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21.

Background

Various megaprostheses are currently available for reconstruction of the proximal femur after tumor resection. This study evaluates the survival and complications of a modular megaprosthesis for reconstruction of the proximal femur.

Materials and methods

We studied the medical files of 109 tumor patients (age range 16–86 years) who underwent proximal femoral reconstruction with the MRP® megaprosthesis from 2002 to 2011. There were 70 patients with metastases, 34 patients with bone sarcomas, and five patients with hematological malignancies; 82 were primary and 27 were revision reconstructions. Mean follow-up was 2.5 years; 31 patients had a minimum five-year follow-up. We evaluated the survival and function of the patients, and the survival and complications of the megaprostheses.

Results

Survival was significantly higher for the patients with bone sarcomas compared to those with metastases and hematological malignancies. Mean MSTS functional score was similar between patients with bone sarcomas and those with hematological malignancies and metastases, and between patients with primary and those with revision reconstructions. Overall survival of the MRP® megaprostheses was 74 % at 5 and 9 years. Fourteen (13.6 %) major complications occurred at a mean period of 1.4 years (range 3 months to 4.5 years); these included infection (5.8 %), dislocation (3.9 %), local recurrence (2.9 %), and acetabular fracture (1 %).

Conclusion

MRP® megaprostheses are a valuable reconstruction option after tumor resection of the proximal femur.
  相似文献   
22.

Purpose

The aim of this study was to analyse factors predicting the diagnostic accuracy of computed tomography (CT)-guided transthoracic fine-needle aspiration (TTFNA) for solid noncalcified, subsolid and mixed pulmonary nodules, with particular attention to those responsible for false negative results with a view to suggesting a method for their correction.

Materials and methods

From January 2007 to March 2010, we retrospectively reviewed the CT images of 198 patients of both sexes (124 males and 74 females; mean age, 70 years; range age, 44–90) used for the guidance of TTFNA of pulmonary nodules. Aspects considered were: lesion size and density, distance from the pleura, and lesion site. Multiplanar reformatted images (MPR) were retrospectively obtained in the sagittal and axial oblique planes relative to needle orientation.

Results

The overall diagnostic accuracy of TTFNA CTguided biopsy was 86% for nodules between 0.7 and 3 cm, 83.3% for those between 0.7 and 1.5 cm, and 92% for those between 2 and 3 cm. Accuracy was 95.1% for solid pulmonary nodules, 84.6% for mixed nodules, and 66.6% for subsolid nodules. The diagnostic accuracy of CT-guided TTFNA in relation to the distance between the nodule and the pleural plane was 95.6% for lesions adhering to the pleura and 83.5% for central ones. The diagnostic accuracy was 84.2% for the pulmonary upper lobe nodules, 85.3% for the lower lobe and 90.9% for those in the lingula and middle lobe. In 75% of false negative and inadequate/insufficient cases the needle was found to lie outside the lesion, after reconstruction of the needle path by MPR.

Conclusions

The positive predictive factors of CT-guided TTFNA are related to the nodule size, density and distance from the pleural plane. The most common negative predictive factor of CT-guided TTFNA is the wrong position of the needle tip, as observed in the sagittal and axial oblique sections of the MPR reconstructions. The diagnostic accuracy of CT-guided TTFNA can therefore be improved by using the MPR technique to plan the needle path during the FNA procedure.  相似文献   
23.
Lymphocyte costimulatory receptors in renal disease and transplantation   总被引:12,自引:0,他引:12  
Cell-to-cell signal exchange during antigen presentation deeply influences the profile and extent of the immune response. Together with the TCR/MHC-mediated signal, accessory signals are provided to the T cell by the antigen-presenting cell (APC), through specific receptor-ligand interactions that represent indispensable costimulation for T-cell activation and survival. The main costimulatory pathways are the B7 family members and the CD40-CD154 receptor-ligand pair. B7-1 and B7-2 costimulate T-cells by binding to CD28. Their binding is prevented by the neoexpression of CTLA4, a CD28 homologue that can deliver a negative signal. Another CD28-like molecule, called ICOS (inducible costimulator), has been described and binds B7RP-1, a third member of the B7 family, but not B7-1 and B7-2. The CD40-CD154 interaction works as a two way costimulatory system by triggering activation signals to both T-cell and APCs. Its importance is highlighted by the discovery that mutations of the CD154 gene are responsible for a severe human immunodeficiency. Disruption of the natural costimulatory interaction was highly effective for prevention and treatment in several experimental models of autoimmune disease and transplant rejection. This review focuses on the most significant advances in understanding the physiopathological events involving costimulatory molecules, and their impact on renal diseases and transplantation.  相似文献   
24.
BackgroundSleeve gastrectomy (SG) leads to esophageal mucosal damage in an elevated percentage of cases, configuring a clinical condition of Barrett’s esophagus (BE) in a proportion as high as 15–18.8%. BE may rarely evolve into esophageal adenocarcinoma (EAC).ObjectivesTo raise awareness of BE as a precancerous lesion which may progress toward malignancy after this popular bariatric procedure.SettingBariatric referral centers, Italy.MethodsAll patients referred to our bariatric center who developed an EAC after SG between 2012 and 2019 were reviewed and consecutively included in this study. The available scientific literature regarding this complication is additionally reviewed.ResultsThe 3 male patients comprised in this case series underwent laparoscopic SG between 2012 and 2015 in different bariatric referral centers. Age and body mass index at baseline ranged from 21–54 years and 43.1–75.6 kg/m2, respectively. All patients were lost to follow-up early after surgery (3.7 ± 1.4 months), and were diagnosed with EAC at a mean of 27.3 ± 7.6 months after SG. The 4 reported cases in the scientific literature developed an EAC at a mean of 32.5 ± 23 months from SG. Overall, a diagnosis of EAC was made approximately 30.3 ± 17.1 months postoperatively, which seems relatively and worryingly early after surgery.ConclusionAlthough the rate and probability of progression from BE to EAC is still not well defined, assuming that the rising popularity and execution of SG leads to a growth in the BE incidence, then the preoperative identification and stratification of cancer risk factors in this subset of patients is strongly encouraged. Clinical and endoscopic follow-ups are essential to allow for prevention and early diagnosis and for epidemiologic data collection purposes.  相似文献   
25.
Conflicting results have been reported on vaccination against hepatitis B virus (HBV) as a prophylaxis against viral recurrence after liver transplantation. We investigated the efficacy of 1‐year, monthly vaccination using an adjuvant 3‐deacylated monophosphoryl‐lipid‐A (MPL) recombinant S vaccine initially administered together with hepatitis B immunoglobulins (HBIg) in 18 patients transplanted for HBV‐related cirrhosis. All received 12 vaccine doses (HBsAg, 20 mcg plus MPL, 50 mcg): the initial six doses (phase I) were administered within 7 days after intravenous HBIg (2000 IU), while the last 6 (phase II) following HBIg withdrawal. All patients received lamivudine during the study. Anti‐HBs titers were determined before each dose and then for 1 year after vaccination. After phase I anti‐HBs titers were greater than 100 IU/l in all patients and in three (16.6%) were greater than 500 IU/l. After phase II 10 patients (55.5%) achieved anti‐HBs titers greater than 100 IU/l and five (27.7%) greater than 500 IU/l. One year after vaccination eight patients (44.4%) maintained anti‐HBs titers greater than 100 IU/l, with a median titer of 234 IU/l (102–1205), and 2 (11.1%) greater than 500 IU/l. One‐year extended monthly vaccination with a MPL‐adjuvant recombinant vaccine induces a sustained protective anti‐HBs response in approximately half of transplant recipients.  相似文献   
26.
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder.  相似文献   
27.

The liver contribution to the biological network underlying physical frailty in aging is underestimated. How best to measure this contribution magnitude and impact on health risk trajectories in frail individuals is not yet entirely clear. We analyzed the association of a novel liver frailty phenotype with the risk of death in older participants of the Salus in Apulia Study cohort. Clinical and physical examination, routine biomarkers, medical history, and anthropometry were analyzed in 1929 older adults (65?+). Physical frailty was classified by Cardiovascular Health Study criteria, and liver fibrosis risk by fibrosis-4 (FIB-4). The liver frailty phenotype was defined as physical frailty plus high-risk liver fibrosis (score?>?2.67). Physical frailty, high-risk liver fibrosis, and liver frailty subjects were compared to subjects without these conditions (non-frail). Proportional Cox regression tested the adjusted association between liver frailty and all-cause mortality for each category. The liver frailty prevalence was relatively low (3.8%), but higher in men (58.1%). Compared to non-frail older subjects, liver frailty subjects were significantly older (effect size (ES)???1.11, 95% confidence interval (CI)???1.35 to???0.87), with a lower education (ES 0.48, 95%CI 0.24 to 0.71) and higher multimorbidity (ES 15.81, 95%CI 4.20 to 27.41). Cox multivariate analyses showed a two-fold increased risk of overall mortality (hazard ratio 2.09, 95%CI 1.16–3.74) even after the adjustment for age, sex, education, and alcohol consumption. The liver frailty phenotype runs twice the risk of overall mortality compared with the non-frail population. This clinical tool, validated in a Southern Italian population, is based on simple sets of measures that can conveniently be assessed also in the primary care setting.

  相似文献   
28.
MED13L haploinsufficiency has recently been described as responsible for syndromic intellectual disability. We planned a search for causative gene variants in seven subjects with intellectual disability and overlapping dysmorphic facial features such as bulbous nasal tip, short mouth and straight eyebrows. We found two de novo frameshift variants in MED13L, consisting in single-nucleotide deletion (c.3765delC) and duplication (c.607dupT). A de novo nonsense variant (c.4420A>T) in MED13L was detected in a further subject in the course of routine whole-exome sequencing. By analyzing the clinical data of our patients along with those recently described in the literature, we confirm that there is a common, recognizable phenotype associated with MED13L haploinsufficiency, which includes intellectual disability and a distinctive facial appearance. Congenital heart diseases are found in some subjects with various degree of severity. Our observation of cleft palate, ataxia, epilepsy and childhood leukemia observed in single cases broadens the known clinical spectrum. Haploinsufficiency for MED13L should be considered in the differential diagnosis of the 1p36 microdeletion syndrome, due to overlapping dysmorphic facial features in some patients. The introduction of massive parallel-sequencing techniques into clinical practice is expected to allow for detection of other causative point variants in MED13L. Analysis of genomic data in connection with deep clinical evaluation of patients could elucidate genetic heterogeneity of the MED13L haploinsufficiency phenotype.  相似文献   
29.
Introduction: Since 2006, biosimilars have been available in several countries worldwide, thus allowing for potential savings in pharmaceutical expenditure. However, there have been numerous debates about the interchangeability of biosimilars and reference products based on concerns of immunogenicity by switching between biological products, which may cause lack of effect and toxicity.

Areas covered: The authors provide the reader with an overview of the different positions of regulatory authorities on the interchangeability and automatic substitution of biosimilars and reference products. Presently, the FDA allows automatic substitution without prescriber intervention if the biosimilar is interchangeable with reference products, while the European Medicines Agency delegate to each single EU member state.

Expert opinion: Different approaches in defining interchangeability and automatic substitution call for harmonization to increase confidence of healthcare professionals and patients about the clinical impact of switching. Networks of electronic healthcare records and administrative databases, potentially linkable to clinical charts and registries may rapidly assess frequency and benefit-risk profile of different switching patterns in routine care at different levels, thus integrating and strengthening pre-marketing evidence.  相似文献   

30.
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