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41.
Uterine fibroids are common tumors of the female pelvis. Uterine artery embolization (UAE) is a minimally invasive alternative procedure in appropriate candidates to conventional myomectomy and hysterectomy for symptomatic uterine leiomyoma, reducing or eliminating leiomyoma-related symptoms of bleeding, bulk, and/or pain. In order to completely block the arterial blood supply to the fibroid, UAE is typically performed in both uterine arteries. At 1 year follow-up, the uterus may shrink by up to 55%, however, a re-growth of the fibroid may occur. The rate of major complications and amenorrhea following this procedure is low, ranging in most series from 1% to 3.5% and 1% to 7%, respectively. Nevertheless, the rate of amenorrhea in women over 45 seems to be higher. Women who wish to become pregnant should be cautioned about potential complications during pregnancy. Despite the lack of controlled studies that compared UAE with conventional surgery, and despite limited extended outcome data, UAE has gained rapid acceptance, primarily because this procedure preserves the uterus, is less invasive, and has less short-term morbidity than most surgical options. This review focuses on recent publications evaluating UAE and concludes that it is a safe treatment option, providing substantial improvement in both health-related quality of life and symptom control for most patients, with a very low rate of major complications. Any centre that offers UAE should adhere to published clinical guidelines, maintain ongoing assessment of quality improvement measures, and observe strict criteria to obtain procedural privileges. The gynecologist is likely to be the primary initial consultant to patients who present with myomas symptoms. Therefore, they must be familiar with the indications, exclusions, outcome expectations, and complications of UAE. When hysterectomy is the only option, UAE should be seriously taken into consideration. At this particular moment in time, data are needed from randomized controlled trials comparing UAE with surgical procedures. Current efforts to provide prospective objective assessment of treatment outcomes and complications after UAE will help to optimize women options and clinical guidelines.  相似文献   
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Background

Recent data support the hypothesis that genetic damage occurring early in life during childhood can play an important role in the development of chronic diseases in adulthood, including cancer.

Objectives

The objective of this paper, part of the MAPEC_LIFE project, is to describe the frequency of micronuclei and meta-nuclear alterations in exfoliated buccal cells of 6–8year-old Italian children recruited in five Italian towns (i.e., Brescia, Torino, Pisa, Perugia and Lecce) with different air pollution levels.

Methods

About 200 children per town were recruited from primary schools. Biological samples were collected twice from the same children, in two different seasons (winter 2014-15 and late spring 2015). Cytogenetic damage was evaluated by the buccal micronucleus cytome assay.

Results

Overall,n?=?1046 children represent the final cohort of the MAPEC_LIFE study. On the whole, the results showed a higher mean MN frequency in winter (0.42?±?0.54‰) than late-spring (0.22?±?0.34‰). MN frequency observed among the five Italian towns showed a trend that follows broadly the levels of air pollution in Italy: the highest MN frequency was observed in Brescia during both seasons, the lowest in Lecce (winter) and Perugia (late-spring).

Conclusions

To the best of our knowledge, the number of recruited children included in the analysis (n?=?1046) is the highest compared to previous studies evaluating the frequency of MN in exfoliated buccal cells so far. MN frequency was associated with winter season and living in towns at various levels of air pollution, suggesting an important role of this exposure in determining early cytogenetic effects.  相似文献   
45.
This work was carried out within the context of an R&D project on morphable polymer matrix composites (PMC), actuated by shape memory alloys (SMA), to be used for active aerodynamic systems in automotives. Critical issues for SMA–polymer integration are analyzed that are mostly related to the limited strength of metal–polymer interfaces. To this aim, materials with suitable thermo-mechanical properties were first selected to avoid premature activation of SMA elements during polymer setting as well as to avoid polymer damage during thermal activation of SMAs. Nonstandard samples were manufactured for both static and fatigue pullout tests under thermo-mechanical loading, which are made of SMA wires embedded in cylindrical resin blocks. Fully coupled thermo-mechanical simulations, including a special constitutive model for SMAs, were also carried out to analyze the stress and temperature distribution in the SMA–polymer samples as obtained from the application of both mechanical loads and thermal activation of the SMA wires. The results highlighted the severe effects of SMA thermal activation on adhesion strength due to the large recovery forces and to the temperature increase at the metal–polymer interface. Samples exhibit a nominal pullout stress of around 940 MPa under static mechanical load, and a marked reduction to 280 MPa was captured under simultaneous application of thermal and mechanical loads. Furthermore, fatigue run-out of 5000 cycles was achieved, under the combination of thermal activation and mechanical loads, at a nominal stress of around 200 MPa. These results represent the main design limitations of SMA/PMC systems in terms of maximum allowable stresses during both static and cyclic actuation.  相似文献   
46.
Radial shock waves therapy (RSWT) differs from extracorporeal shock waves therapy (ESWT) in that it produces a non-focused wave that is dissipated radially at the skin. Few studies have yet explored the effects of RSWT on bone tissue. Osteoblasts in culture flasks were studied by polymerase chain reaction after treatment with RSW (500 impulses, 0.05?mJ/mm2). An inhibited osteoblastogenesis was observed, with a statistically significant reduction in type 1 collagen, osterix, bone sialoprotein and receptor activator NF kappa ligand expression at 24 and 48?h, of osteocalcin at 24, 48 and 72?h, and osteopontin at 48 and 72?h. These findings show that RSWT is not indicated for treatment of delayed fracture union, pseudoarthrosis, and complex regional pain syndrome. The observed reduction in the receptor activator of nuclear factor-kB ligand/osteoprotegerin ratio suggests that it has an inhibiting effect on osteoclastogenesis, which could make it a useful tool for applications in proliferative diseases.  相似文献   
47.
Purpose : Awareness and knowledge of Assistive Technology (AT) are key factors in supporting empowerment of people with disabilities. They also greatly contribute to the success of AT solutions. Based on the findings of the EUSTAT study--an international project within the Telematics Application Programme of the European Commission--this paper offers a synthesis of the guidelines developed for those who organize educational activities on AT addressed towards end-users. Results : The educational process is looked at within an empowerment perspective rather that as a mere transmission of notions. The effectiveness of education should be evaluated in relation to the increased ability of end users to make use of AT knowledge for improving their quality of life, and becoming informed, demanding and responsible consumers of AT products and services. Conclusion : To such end a number of critical factors are identified, and ways to address them are discussed. Finally, a case study is reported as an example of an effective AT educational curriculum for end-users.  相似文献   
48.
The hypothesis that extracellular truncation of the common receptor subunit for interleukin-3 (IL-3), granulocyte-macrophage colony- stimulating factor, and IL-5 (h beta c) can lead to ligand-independent activation was tested by infecting factor-dependent hematopoietic cell lines with retroviruses encoding truncated forms of h beta c. A truncation, resembling that in v-Mpl, and retaining 45 h beta c-derived extracellular residues, led to constitutive activation in the murine myeloid cell line, FDC-P1. However, infection of cells with retrovirus encoding a more severely truncated receptor, retaining only 7 h beta c- derived extracellular residues, did not confer factor independence on these cells. These experiments show that truncation activates the receptor and define a 37-amino acid segment of h beta c (H395-A431) which contains two motifs conserved throughout the cytokine receptor superfamily (consensus Y/H XX R/Q VR and WSXWS), as essential for factor-independent signaling. The mechanism of activation was also investigated in less severe truncations. A receptor that retains the entire membrane-proximal domain (domain 4) also conferred factor independent growth on FDC-P1 cells; however, a retrovirus encoding a truncated form of h beta c having two intact membrane proximal domains did not have this ability, suggesting that domain 3 may have an inhibitory role in h beta c. The ability of these receptors to confer factor independence was cell specific as demonstrated by their inability to confer factor-independent growth when introduced into the murine IL-3-dependent pro-B cell line BaF-B03. These results are consistent with a model in which activation requires unmasking of an interactive receptor surface in domain 4 and association with a myeloid- specific receptor or accessory component. We suggest that in the absence of ligand intramolecular interactions prevent inappropriate signaling.  相似文献   
49.

Purpose

High-dose-rate, multicatheter interstitial brachytherapy is technically complex and operator-dependent, requiring lengthy training and specialized skills. Furthermore, until the advent of contouring on computerized tomography (CT) images, difficulties existed in locating the target volume precisely. The present article reports the results of a study that aimed at producing and validating a 3D-printed template to aid in target volume localization for multicatheter interstitial brachytherapy in patients with breast cancer.

Methods and Materials

Thirteen patients, candidates for accelerated partial breast irradiation or boost, were enrolled in the study. The target volume was defined on CT slices, and a template with empty spaces corresponding to the target volume projection on the patient's skin was produced by a 3D printer. The procedure was compared with the standard method followed in our center (1) visually, by assessing overlap between the target volume projections on the patient's skin, (2) by X-ray findings, and (3) by intraclass correlation coefficient.

Results

Visual assessment and X-ray findings showed the 3D-printed target volume always fell within the standard volume in all 13 patients. The intraclass correlation coefficient indicated moderate agreement for both the medial and the lateral skin projections.

Conclusions

The 3-D printed templates constitute a quick, easy, and reliable method to localize the target volume for high-dose-rate interstitial multicathether brachytherapy in patients with breast cancer and can safely be used in clinical practice.  相似文献   
50.
Introduction: Complex regional pain syndromes (CRPS) are rare painful conditions characterized by considerable variability in possible triggering factors, usually traumatic, and in the clinical scenario. The limited knowledge of the pathophysiological mechanisms has led to countless treatment attempts with multiple conservative and surgical options that act by different mechanisms of action.

Areas covered: In this narrative review, the authors discuss key points about CRPS definitions, diagnostic criteria and pitfalls, pathophysiological hypotheses, and treatment strategies with particular reference to pharmacotherapy. The article was based on a literature search using PubMed while the available guidelines for the management of CRPS were also examined.

Expert opinion: According to the quality of evidence, pharmacological interventions for CRPS seem to be more effective all the more so when they act on peripheral mechanisms, particularly on nociceptive pain, and when applied early in the disease, while reliable evidence about central mechanisms of chronic pain in CRPS is lacking. In our opinion, drug therapy should be preferred as early as possible, particularly in warm forms of CRPS to prevent significant functional limitation, psychological distress, and social and economic fallout.  相似文献   

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