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101.
Introduction: In light of the recent development of new soft materials, nanostructured self-assembled systems have attracted attention in a variety of technological fields of high social impact. Cyclodextrin nanosponges (CDNS) represent a new and highly versatile class of cross-linked cyclodextrin (CD)-based nanoporous polymers. Their intriguing properties, including safety, biodegradability, negligible toxicity, marked swelling behavior, superior inclusion capability with respect to native CD, are the bases for potential for applications in drug delivery, tissue engineering and regenerative medicine.

Areas covered: We report on the state-of-art concerning a detailed characterization of structural and dynamical features of CDNS explored by the combined use of different and complementary techniques, such as Fourier transform infrared absorption in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopies, and high resolution magic angle spinning (HR-MAS) NMR spectroscopy. The ambitious objective is to furnish an exhaustive survey of the role played by hydrophobic and hydrophilic groups within the cross-linked network, in dry and swollen states, in determining the macroscopic functional features of CDNS.

Expert opinion: The reported results may significantly contribute in the rational design and optimization of new stimuli-responsive systems exhibiting tunable inclusion/release properties, adapted to the therapeutic demands of pathology.  相似文献   

102.
Journal of Neurology - Compression of the median nerve at the carpal tunnel can give demyelinating features and result in distal motor latency (DML) prolongation fulfilling the EFNS/PNS...  相似文献   
103.
Neurological Sciences - Up to 50% of motor neuron disease (MND) patients show neuropsychological deficits which negatively affect prognosis and care. However, disability-related logistical issues...  相似文献   
104.
Neurological Sciences - Dysphagia is a common symptom during the trajectory of ALS, and it can significantly impact on the quality of life and prognosis of patients. Nowadays, no specific tool for...  相似文献   
105.
A remote cerebellar hemorrhage (RCH) is a spontaneous bleeding in the posterior fossa, which can be rarely observed as a complication of spine surgery. As well as for RCH reported after supratentorial procedures, it shows a characteristic bleeding pattern defined “zebra sign”. Nowadays, RCH pathophysiology still remains unknown. We performed a comprehensive review, collecting all cases of RCH after spine surgery reported in literature in order to identify the procedures most frequently associated with RCH and the possible risk factors. We assessed percentages of incidence and 95 % confidence interval of all demographic, neuroradiological, and clinical features. Univariate and multivariate analyses were used to evaluate their association with outcome. We included 44 articles reporting 57 patients with mean age of 57.6?±?13.9 years and a male/female ratio of 23/34. A RCH was more frequently reported as a complication of decompressive procedures for spinal canal stenosis, particularly when associated with instrumented fusion, followed by spinal tumor debulking and disc herniation removal. In the majority of cases, RCH occurrence was characterized by progressive impairment of consciousness, whereas some patients complained non-specific symptoms. Coagulation disorders, hypertension, and placement of postoperative subfascial drainages were the most frequently reported risk factors. The occurrence of intraoperative dural lesions was described in about 93 % of patients. Zebra sign was the most common bleeding pattern (about 43 % of cases) followed by parenchymal hematoma (37.5 %) and mixed hemorrhage (about 20 %). Impairment of consciousness at clinical onset and intake of anticoagulants/antiplatelets appeared associated with poor outcome at univariate analysis. However, more than 75 % of patients showed a good outcome and a RCH often appeared as a benign and self-limiting condition, which usually did not require surgical treatment, but only prolonged clinical surveillance, unless of the occurrence of complications.  相似文献   
106.

Background

Sirtuins (SIRTs), ubiquitous deacetylases, are main regulators of energy homeostasis and metabolism. SIRT1 has a positive impact on obesity, diabetes mellitus, liver steatosis, and other metabolic disorders. Lean subjects have higher expression of SIRT1 in the adipose tissue compared to obese. However, it is not known whether weight loss associates with changes in blood SIRT1. We evaluated the effect of weight loss on circulating SIRT1, metabolic parameters, and body composition.

Methods

Thirty-two obese subjects were studied before and 6 months after BioEnterics® Intragastric Balloon (BIB®) [22 patients, BMI 41.82?±?6.28 kg/m2] or hypocaloric diet [10 patients, BMI 38.95?±?6.90 kg/m2]. Plasma SIRT1, body composition, measures of metabolic syndrome (waist circumference, fasting plasma glucose, blood pressure, HDL cholesterol, triglycerides), and inflammation markers (ESR, CRP, fibrinogen) were recorded.

Results

SIRT1 levels showed a significant increase, together with a significant reduction of BMI, excess body weight, and total fat mass either after BIB or diet intervention. The percent excess body weight loss was 33.73?±?19.06 and 22.08?±?11.62 % after BIB and diet, respectively, a trend toward a metabolic and inflammatory amelioration was observed with both treatments. Negative correlation between SIRT1 and % fat mass (BIB, ρ?=??0.537, p?=?0.017; diet, ρ?=??0.638, p?=?0.047) was also seen.

Conclusions

The reduction of fat mass associates with increased plasma SIRT1 indicating that, besides tissue levels, circulating SIRT1 is stimulated by a negative caloric balance. The rise of plasma SIRT1 may represent a parameter associating with fat loss rather than weight lowering regardless of the weight reduction system method used.
  相似文献   
107.
108.
BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.  相似文献   
109.
110.

Objective

To calculate the prevalence of common gain of function gene mutations in patients with different clinical manifestations of venous thromboembolism.

Design and setting

Case–control study in two hospitals in Italy.

Participants

387 patients with venous thromboembolism and 286 controls.

Main measures

Factor V (FV) Leiden, factor II (FII) A20210 and JAK2 V617F mutations.

Results

Among patients with deep vein thrombosis in one leg, 23 (20.9%) carried FV Leiden and FII A20210 mutations. Similar figures were observed in patients with cerebral vein thrombosis (CVT; n = 9; 20.0%) and in patients presenting with splanchnic vein thrombosis (SVT; n = 26; 18.7%). A lower prevalence was obtained in patients with retinal vein thrombosis (n = 11; 11.8%). The JAK2 F617 mutant allele was found in 27 (21.1%) patients with SVT, but in none of the patients presenting with a thrombotic event from different districts. 13 of the 27 JAK2 V617F‐positive subjects with SVT were previously known to have a myeloproliferative disease (MPD). Three other patients had a diagnosis of MPD after the occurrence of the thrombotic event.

Conclusion

Carriership of FV Leiden or FII A20210 mutations identifies an at‐risk condition for venous thrombosis in the lower extremities, SVT or CVT. In patients with SVT, screening for the JAK2 V617F mutation may be useful in recognising patients who should be carefully observed for the subsequent development of overt MPD. Thus, genetic tests may play a different role, various clinical manifestations of venous thromboembolism being associated with distinct risk profiles.Venous thrombosis is the third most common cardiovascular affliction after ischaemic heart disease and stroke.1 It is common in Caucasians, affecting 1 in 1000 individuals every year, and is strongly associated with life‐threatening pulmonary embolism. The pathogenesis of venous thrombosis is multifactorial, involving acquired and genetic factors. In addition to circumstantial predisposing factors (eg, surgery, pregnancy, immobilisation and malignancy), genetic predisposition due to molecular abnormalities of components of the coagulation pathway have been found in subjects who had had thromboembolic disease.2 Abnormalities within the gene loci encoding for natural anticoagulants (antithrombin, protein C and protein S) and for fibrinogen have been shown to be rather uncommon risk factors for venous thrombosis.3 In patients of European ancestry, common gain‐of‐function mutations within the gene of the coagulation factor V (FV Leiden mutation) and the factor II (FII) gene (a G→A transition at nucleotide position 20210) have been shown to account for a large number of cases of thromboembolism.2,3 Recently, the JAK2 V617F mutation, an acquired somatic event occurring in most patients with polycythaemia vera (PV) and in about half of the patients with essential thrombocythaemia (ET) or myelofibrosis (MF),4,5,6,7,8 has been found in a high proportion of patients with Budd–Chiari syndrome9 and in patients without cirrhosis with portal and mesenteric venous thrombosis, a heterogeneous group of disorders.10Thus, the high frequency of common mutations in patients presenting with venous thromboembolism raised the hypothesis that it can be considered as a feasible and practical approach for the identification of predisposing genetic risk factors. Genetic test results can better inform individuals about their risk of recurrence and appropriated tailored strategies for the prevention of venous thrombosis.However, depending on the different clinical manifestations of venous thromboembolism, the prevalence of inherited coagulation abnormalities varies, suggesting pathogenic differences.11,12,13 These data support the hypothesis that mechanistic differences are involved in the pathogenesis of thrombosis in different clinical settings. Thus, before considering whether it is advisable to investigate a subject for inherited risk factors, we need to know the prevalence of these risk factors in different clinical settings.We, therefore, calculated the prevalence of inherited thrombophilic risk factors in a large cohort of patients referred for a thrombophilic investigation with different clinical manifestations of venous thromboembolism.  相似文献   
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