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41.
Thymic neuroendocrine tumors (TNET) are rare primary epithelial neoplasms of the thymus. This study aimed to determine clinically relevant parameters for their classification and for therapeutic decisions. We performed a comprehensive histological, clinical, and genetic study of 73 TNET cases (13 thymic typical carcinoids [TTC], 40 thymic atypical carcinoids [TAC], and 20 high‐grade neuroendocrine carcinomas [HGNEC] of the thymus), contributed by multiple institutions. The mean number of chromosomal imbalances per tumor was 0.8 in TTC (31% aberrant cases) versus 1.1 in TAC (44% aberrant cases) versus 4.7 in HGNEC (75% aberrant cases). Gains of 8q24 (MYC gene locus) were the most frequent alteration and one of the overlapping features between carcinoids and HGNEC. The 5‐year survival rates for TTC, TAC, and HGNEC were 100, 60, and 30%. The 10‐year survival rates for TTC and TAC were 50 and 30% (P = 0.002). Predictive mitotic cut‐off values for TTC versus TAC were 2.5 per 10 high‐power fields (HPF; indicating a higher death rate, P = 0.062) and 15 per 10 HPF (indicating higher risk of recurrence, P = 0.036) for separating HGNEC from TAC. We conclude that the current histopathologic classifications of TNET reflect tumor biology and provide important information for therapeutic management. © 2014 Wiley Periodicals, Inc.  相似文献   
42.
The present study evaluated dynamic coagulation profiles, platelet aggregation, and thrombin generation in whole blood (WB) from eight children with thrombocytopenia during chemotherapy, and the haemostatic potential of platelets (+60 × 109/l), recombinant factor VIIa (rFVIIa – NovoSeven®), and a potent rFVIIa analogue (NN1731) both at 1 and 4 μg/ml. Dynamic WB coagulation profiles were recorded by thrombelastometry employing activation with tissue factor (TF – Innovin®) at low concentrations. The baseline WB coagulation patterns were characterised by a prolonged clotting time (CT) and a pronounced reduction in clot propagation (MaxVel). WB platelet aggregation signal was five times lower in the study group compared with measurements in modelled thrombocytopenic WB from healthy volunteers. In vitro addition of fresh platelets reversed the coagulopathy. Addition of rFVIIa induced no significant changes in the thrombelastographic profile, whereas spiking with NN1731 shortened the CT significantly. The changes in WB thrombin generation reflected the changes in the MaxVel. In modeled thrombocytopenic WB from healthy individuals, both rFVIIa and NN1731 exhibited a pronounced haemostatic effect with NN1731 showing greater potency than rFVIIa. Compromised platelet function in the study group was assumingly responsible for the weakened haemostatic potential of rFVIIa as well as that of NN1731.  相似文献   
43.
Recent studies suggest that the oligomers of short amyloid beta (Aβ) peptides such as Aβ25–35 as well as full-length Aβ peptides (i.e. Aβ1–40 and Aβ1–42 peptides) are responsible for synaptic dysfunction and/or neuronal loss in Alzheimer's disease (AD). Among antioxidant phytochemicals derived from fruit and vegetables, cyanidin 3-O-glucoside (Cy-3G) has recently gained attention for its neuroprotective properties. In this in vitro study, we demonstrated that Cy-3G can inhibit Aβ25–35 spontaneous aggregation into oligomers and their neurotoxicity in human neuronal SH-SY5Y cells. In particular, the pre- and co-treatment of SH-SY5Y cells with Cy-3G reduced the neuronal death, in terms of apoptosis and necrosis, elicited by Aβ25–35 oligomers. Cy-3G also shows the interesting ability to prevent the early events leading to neuronal death such as the Aβ25–35 oligomer binding to plasma membrane and the subsequent membrane integrity loss. Taken together, these findings suggest that Cy-3G may be considered a phytochemical with neuroprotective properties useful in finding potential drug or food supplements for the therapy of AD.  相似文献   
44.
45.
BACKGROUND. Alterations in the growth hormone (GH)/insulin‐like growth factor I (IGF‐I) axis are associated with increased cardiovascular morbidity and mortality, but previous studies have yielded conflicting results. In addition, the T1169A polymorphism in the GH1 gene has been associated with IGF‐I levels.

AIMS. To investigate whether IGF‐I concentrations and the T1169A polymorphism of the GH1 gene are associated with cardiovascular risk factors and the intima media thickness (IMT) of the carotid artery.

METHODS. Fasting plasma IGF‐I concentrations (n = 1008) were measured in a large population‐based OPERA (Oulu Project Elucidating Risk of Atherosclerosis) cohort. Genotype variants were determined by the restriction fragment length polymorphism method.

RESULTS. Low IGF‐I concentrations associated with several cardiovascular risk factors including age, adiposity, and high triglyceride, fasting insulin and C‐reactive protein concentrations in the analysis of all subjects. In the multivariate models, however, IGF‐I concentrations were positively associated with the mean IMT of women (ß = 0.127, P = 0.009) whereas the association in men was weaker and negative (ß = ?0.088, P = 0.034). The 1169A allele was associated with low low‐density lipoprotein cholesterol in both sexes and with low systolic blood pressure levels in women.

CONCLUSIONS. IGF‐I concentrations were associated with several traditional cardiovascular risk factors. The observed gender difference in the association between IGF‐I concentrations and carotid artery atherosclerosis warrants further study. The GH1 1169A allele may be associated with a favourable metabolic profile.  相似文献   
46.
Palytoxin (PlTX) is one of the largest compound present in nature and, with its strong ability to modify the normal function of different biological systems, is also classified as one of the most potent biotoxins. Many alterations are triggered by PlTX, directly or indirectly related to its interaction with Na+,K+-ATPase and the consequent conversion of this ion pump into a non-specific cation channel. The resulting perturbation of Na+, K+, Ca2+ and H+ ion fluxes is the driving force of PlTX-induced cytotoxic events, culminating with system disruption and, finally, cell death. The modifications in the distribution of these ions across the plasma membrane play key roles in the promotion of the PlTX-induced cytolytic and cytotoxic responses. In this scenario, PlTX-specific cytolysis can be part, but might not necessarily represent a unique aspect of the cytotoxic effects of the toxin. Owing to the complex array of responses, some of them being cell-type-specific and/or affected by experimental conditions, the distinction between cytolytic and cytotoxic events becomes ill-defined, but the two responses show distinct features, whose further characterization could contribute to a better understanding of the molecular mechanism of cellular effects induced by PlTX.  相似文献   
47.
Synthesis and antitumor activity of new E-3-(2-chloro-3-indolylmethylene)-1,3-dihydroindol-2-ones are described. All compounds prepared were active in the primary test (three human cell lines) and entered the second level (60 human cell lines). The most active antitumor derivatives bear the same substituents in the chloroindole ring and are not CDK1 inhibitors. A COMPARE analysis showed that they could act as tubulin binders. In most cell lines, E-3-(2-chloro-5-methoxy-6-methyl-3-indolylmethylene)-1,3-dihydroindol-2-one was a growth inhibitor more potent than vincristine.  相似文献   
48.
Closing the gap between research and clinical practice is nowadays considered a priority in outcome studies. Survey studies in community settings having as their main aim the multidimensional measure of outcome of mental health care interventions, including the use of standardised instruments administered as part of the routine clinical activities in mental health services, have recently started to be planned in various countries, but have encountered several difficulties. A naturalistic, longitudinal study aimed to assess the outcome of care provided by a community-based mental health service, the South Verona Outcome Project, has been conducted in Italy starting from the beginning of the 90's and is running since then. This paper: a) describes a series of methodological aspects of the South Verona Outcome Project, such as instruments, study design, inclusion and exclusion criteria, training of the staff, and focuses on strategies used so to ensure feasibility of the assessment and good quality of the data; b) summarises some results of the study, characteristics of feed-back provided, and outputs; c) discusses the problems faced, the impact of this approach on service provision, its limitations and future perspectives.  相似文献   
49.
PURPOSE: This collaborative study by three Italian groups of child neuropsychiatrists was carried on to evaluate the efficacy and safety of the classic 4:1 ketogenic diet as add-on treatment in refractory partial or generalized epilepsy in children, adolescents and young adults. METHODS: We performed a prospective add-on study in 56 refractory epilepsy young patients (age 1-23 years, mean 10.4 years), all with both symptomatic and cryptogenic, generalized or partial epilepsies. Child neuropsychiatrists worked with nutritional team for sample selection and patients management. The ketogenic diet was added to the baseline antiepileptic drugs and the efficacy was rated according to seizure type and frequency. During treatment, seizure frequency, side effects, urine and blood ketone levels and other parameters were systematically evaluated. RESULTS: Patients have been treated for 1-18 months (mean 5 months). A >50% reduction in seizure frequency was gained in 37.5 and 26.8% of patients after 3 and 6 months, respectively, at 12 months, this number fell by 8.9%. No significant relationship between diet efficacy and seizure or epilepsy type, age at diet onset, sex and etiology of epilepsy was noted. Nevertheless, it seems noteworthy that 64% of our patients with neuronal migration disorders improved on this diet. Adverse effects occurred, mainly in the first weeks of treatment, in 32 patients (57.1%), but were generally mild and transient. In seven patients (12.5%) it was possible to withdraw one to two AED after 3-4 months on ketogenic diet. CONCLUSION: This initial experience with the ketogenic diet was effective in difficult-to-treat patients with partial and generalized epilepsies, though its efficacy dropped significantly by 9-12 months.  相似文献   
50.
The state of the art with regard to the employment of various cytokine-based tumor immunotherapy strategies and their mechanisms of action are critically reviewed. As matters now stand, adoptive transfer of LAK cells or tumor infiltrating lymphocytes together with high doses of IL-2 constitutes the only immunologic way to hinder tumor growth in advanced stages of cancer. On the other hand, many experimental data show that the local presence of cytokines, either injected repeatedly at tumor site or released by cytokine-gene engineered tumor cells, arouses immunogenicity in apparently nonimmunogenic spontaneous tumors. By strengthening the notion that most tumors are potentially immunogenic, these f'mdings offer substantial evidence to stres~ the potential use ofcytoklnes as a component of new tumor vaccines.  相似文献   
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