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PurposeTo investigate the safety and clinical efficacy of bipolar radiofrequency ablation (b-RFA) with increased (> 70 °C) target temperature for the treatment of spine metastases with the intent of achieving pain relief or local tumor control.Materials and methodsThirty-one patients with a total of 37 metastases who were treated with b-RFA with increased temperature and vertebroplasty from January 2016 to May 2019 were retrospectively included. There were 20 women and 11 men with a mean age of 62.4 ± 10.5 (SD) years (range: 40–78 years). Patients and metastases characteristics, procedure details and clinical outcomes were analyzed.ResultsMetastases were predominantly located in lumbar (22/37; 59.5%) or thoracic spine (13/37; 35.1%). Mean target temperature was 88.4 ± 3.5 (SD) °C (range: 70–90 °C). Technical success was 100% (37/37 metastases). One (1/37; 2.7%) major complication unrelated to b-RFA was reported. One (1/37; 2.7%) metastasis was lost to follow-up. Favorable outcome was noted in patients receiving b-RFA for pain management (16/20 metastases; 80%; mean follow-up, 3.4 ± 2.9 [SD] months) or with oligometastatic/oligoprogressive disease (6/6 metastases; 100%; mean follow-up, 5.0 ± 4.6 [SD] months). In patients receiving b-RFA to prevent complications, favorable outcome was noted in 6/10 metastases (60%; mean follow-up, 3.8 ± 4.8 [SD] months).ConclusionsB-RFA with increased target temperature has an excellent safety profile and results in high rates of pain relief and local metastasis control in patients with oligometastatic/oligoprogressive disease. Suboptimal results are achieved in patients receiving b-RFA to prevent complications related to the growth of the index tumor.  相似文献   
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BACKGROUND: The relative contribution to the olfactory dysfunction of the lesions in the specific brain regions involved in olfaction compared with the lesions scattered all over the rest of the brain has not been fully clarified yet in patients with multiple sclerosis (MS). The concurrent use of Magnetic Resonance Imaging (MRI) and a standardized test of odor identification ability now permits to study the relation between smell loss and the extent of white matter abnormalities. METHODS: We tested the olfactory function of 40 patients with definite MS and of 40 age-sex- and smoking-habit-matched healthy controls by using the Cross Cultural Smell Identification Test. We measured also the lesion load on T2-weighted images in the inferior-frontal and temporal lobes and in the rest of the brain in MS patients. Therefore, we tried to correlate measures of lesion load and smell test scores. RESULTS: A robust correlation was demonstrated between MR measures of lesion load in the white matter of the olfactory brain region and smell loss (r=-0. 739, P<0.0001). A significant relationship has been found even after taking potential confounding factors, such as sex, age, disease duration, disability, anxiety and depression, into account (r=-0.90, P<0.0001). CONCLUSIONS: Our findings show, in MS patients with stable neurological impairment and no recent disease exacerbation, a correlation between smell loss and the lesion load in the regions of the brain involved in olfaction and support the theory that the extent and severity of MRI abnormalities in specific brain regions are related to the presence of selective neurologic and neuropsychologic impairment.  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   
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BACKGROUND: Mixed cryoglobulinemia (MC) is a systemic vasculitis secondary to circulating immune complex deposition in the small vessels. In the overwhelming majority of patients, hepatitis C virus (HCV) infection represents the triggering factor of the disease. MC is characterized by multiple organ involvement, mainly skin, liver, renal, peripheral nerves, and less frequently by widespread vasculitis and cancer. OBJECTIVES: To investigate the demographic, clinical, serologic features, and survival in a large series of MC patients. METHODS: The study included 231 MC patients recruited between 1972 and 2001 at the Rheumatology Unit of the University of Pisa. All patients underwent wide clinicoserologic and virologic assessment. Cumulative survival rates were computed by the Kaplan-Meier method; moreover, the prognostic relevance of the main variables was investigated by Cox model analysis. RESULTS: In 92% of cases, the presence of HCV infection was demonstrated (anti-HCV antibody, 92%; HCV RNA, 90%), whereas hepatitis B virus (HBV) represented the possible causative agent in only 1.8% of patients (HBV DNA). Clinically, the MC syndrome followed a relatively benign clinical course in over 50% of cases, whereas a moderate-severe clinical course was observed in one third of patients whose prognosis was severely affected by renal and/or liver failure. In a limited, but significant, percentage (15%) of individuals, the disease was complicated by a malignancy, ie, B-cell lymphoma, and less frequently by hepatocellular carcinoma, or thyroid cancer. The survival study by the Kaplan-Meier method revealed a significantly lower cumulative 10th-year survival, calculated from time of diagnosis, in MC patients compared with expected death in the age- and sex-matched general population. Moreover, significantly lower survival rates were observed in males and in subjects with renal involvement. The multivariate analysis by the Cox proportional hazard regression model further supported the above findings: an increased mortality risk of 98% was observed for male gender (male/female hazard ratio, 1.978) and of 197% in patients with, compared with those without, renal involvement (hazard ratio, 2.967). At the end of the follow-up, 97 patients were deceased, and in 79 of 97 patients, the causes of death were ascertained: nephropathy (33%), malignancies (23%), liver involvement (13%), and diffuse vasculitis (13%) were the most frequent causes of death. CONCLUSIONS: Careful patient monitoring is recommended for a timely diagnosis of life-threatening MC complications, mainly nephropathy, widespread vasculitis, and B-cell lymphoma or other malignancies.  相似文献   
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Recent advances in social neuroscience research have unveiled the neurophysiological correlates of race and intergroup processing. However, little is known about the neural mechanisms underlying intergroup empathy. Combining event‐related fMRI with measurements of pupil dilation as an index of autonomic reactivity, we explored how race and group membership affect empathy‐related responses. White and Black subjects were presented with video clips depicting white, black, and unfamiliar violet‐skinned hands being either painfully penetrated by a syringe or being touched by a Q‐tip. Both hemodynamic activity within areas known to be involved in the processing of first and third‐person emotional experiences of pain, i.e., bilateral anterior insula, and autonomic reactivity were greater for the pain experienced by own‐race compared to that of other‐race and violet models. Interestingly, greater implicit racial bias predicted increased activity within the left anterior insula during the observation of own‐race pain relative to other‐race pain. Our findings highlight the close link between group‐based segregation and empathic processing. Moreover, they demonstrate the relative influence of culturally acquired implicit attitudes and perceived similarity/familiarity with the target in shaping emotional responses to others' physical pain. Hum Brain Mapp 34:3168–3181, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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The study of SARS-CoV-2 positive pregnant women is of some importance for gynecologists, obstetricians, neonatologists and women themselves. In recent months, new works have tried to clarify what happens at the fetal–placental level in women positive for the virus, and different pathogenesis mechanisms have been proposed. Here, we present the results of a large series of placentas of Coronavirus disease (COVID) positive women, in a reference center for COVID-positive pregnancies, on which we conducted histological, immunohistochemical and electron microscopy investigations. A case–control study was conducted in order to highlight any histopathological alterations attributable to SARS-CoV-2. The prevalence of maternal vascular malperfusion was not significantly different between cases and controls (54.3% vs. 43.7% p = 0.19), whereas the differences with regard to fetal vascular malperfusion (21.1% vs. 4.2% p < 0.001) were significant. More frequent in cases with respect to controls were decidual arteriopathy (40.9% vs. 1.4% p < 0.0001), decidual inflammation (32.4% vs. 0.7% p < 0.0001), perivillous fibrin deposition (36.6% vs. 3.5% p < 0.0001) and fetal vessel thrombi (22.5% vs. 0.7% p < 0.0001). No significant differences in the percentage of terminal villous hyperplasia and chorioamnionitis were observed between the two groups. As the pandemic continues, these studies will become more urgent in order to clarify the possible mechanism of maternal–fetal transmission of the virus.  相似文献   
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The current coronavirus pandemic has affected, in a short time, various and different areas of medicine. Among these, the obstetric field has certainly been touched in full, and the knowledge of the mechanisms potentially responsible for placental damage from SARS-CoV-2 occupy a certain importance. Here we present here a rare case of dichorionic twins born at 30 weeks and 4 days of amenorrhea, one of whom died in the first few hours of life after placental damages potentially related to SARS-CoV-2. We also propose a brief review of the current literature giving ample emphasis to similar cases described.  相似文献   
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