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981.
The central visual system of white zebra finches is physiologically and anatomically different from normally coloured (wild type) animals. The main difference to normal birds is an enhanced response to ipsilateral stimulation in all areas of the tectofugal visual pathway. Previous experiments indicated that besides an enhancement of recrossing fibers, it might be a lack of inhibition which causes this effect. We show here that such an explanation can only be true for a part of the entopallium, the telencephalic station of this projection. Only within the so-called perientopallium, the number of GABAergic neurons is strongly reduced, while there is no significant difference between white and wild type birds in the other visual areas. It is speculated that these neurons in normal birds inhibit ipsilateral input conveyed by the second visual projection in birds, the thalamofugal pathway. 相似文献
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984.
Giulia M. Stella Roberta Scabini Simona Inghilleri Francesca Cemmi Simona Corso Ernesto Pozzi Patrizia Morbini Adele Valentini Roberto Dore Simona Ferrari Maurizio Luisetti Michele Zorzetto 《Journal of cancer research and clinical oncology》2013,139(8):1327-1335
Purpose
Knowledge of tumor mutational status has become a priority for effective NSCLC-tailored treatment. NSCLC diagnosis is more often reached through biopsy; thus, there is a clear need to implement for routine tumor molecular profiling on small cytological samples. This work aims to screen and compare the EGFR and KRAS mutational prevalence in fresh tumor cells and in corresponding routinely processed samples derived from trans-thoracic fine-needle aspiration. The latter currently represents the most appropriate diagnostic procedure in case of peripheral lesions, such as adenocarcinomas, which account for almost 40 % of all NSCLCs and for the highest EGFR mutational rates.Methods
Two hundred and forty-four patients carrying peripheral lung masses underwent CT-guided aspiration. The obtained material was split, and a part was addressed to conventional histopathological analysis while the remaining one was stored at ?20 °C. In case of confirmation of adenocarcinoma, tumor genomic DNA was extracted from both fresh and fixed material, and EGFR and KRAS sequencing was performed.Results
We identified 136 adenocarcinomas; from 134, we could recover enough material for the study. A full match was demonstrated between EGFR/KRAS mutational prevalences through the two approaches tested. We found EGFR mutations in 13 patients (9.7 %); 7 were females and 11 never or former smokers. KRAS mutations occurred in 20 (14.9 %) patients. EGFR and KRAS mutations were mutually exclusive.Conclusions
Mutational screening on fresh cancer cells is an achievable, safe and cost-effective procedure which might allow routinely tumor molecular profiling as powerful integration of conventional histopathological analysis. 相似文献985.
Federica Vinciguerra Roberto Baratta Maria Grazia Farina Patrizia Tita Giuseppa Padova Riccardo Vigneri Lucia Frittitta 《Acta diabetologica》2013,50(3):443-449
The prevalence of very severe obesity has increased progressively and faster than other classes of obesity over the last years. It is unclear whether the prevalence of obesity-related complications and health risks increases progressively or reaches a plateau above a certain degree of obesity. The aim of our study was to investigate whether the severity of obesity was correlated with the prevalence of type 2 diabetes mellitus (T2DM), impaired fasting glucose, impaired glucose tolerance (IGT), metabolic syndrome (MS), and cardiovascular diseases (CVDs) in a large cohort of patients with different degrees of obesity. A cross-sectional study was conducted in 938 obese patients without a previous diagnosis of diabetes. Patients were assigned to different categories of obesity: mild-moderate obesity (BMI 30–39.9 kg/m2), morbid obesity (BMI 40–49.9 kg/m2), and super-obesity (SO, BMI ≥50 kg/m2). The prevalence of IGF, IGT, screen-detected T2DM, MS, and CVD was higher in SO patients than in the other groups. Interestingly, the association between SO and either MS or CVD was independent of glucose tolerance status, indicating that factors other than glucose metabolism also favor cardio-metabolic complications in obese patients. In patients without screen-detected T2DM (n = 807), insulin sensitivity and secretion OGTT-derived indexes indicated that SO patients had the worst glucose homeostasis relative to the other categories of obesity, which was indicated by the most reduced disposition index in these patients, a predictor of future T2DM. In conclusion, SO patients have an extremely high prevalence of glucose metabolism deterioration, and cardio-metabolic complications are more prevalent in these patients compared to less obese patients. 相似文献
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987.
Yasmin Pasha Lucy Pickard Patrizia Cohen Matthew Banks 《Scandinavian journal of gastroenterology》2013,48(9):1151-1152
Chemotactic, phagocytic, and oxidative metabolic activity of exudative leukocytes was measured in patients with Crohn's disease (n = 20) and with ulcerative colitis (n = 20). Unstimulated and casein-stimulated migration in Boyden chambers did not differ from that of healthy controls (n = 21). Patients with Crohn's disease had reduced serum-independent phagocytosis compared with healthy controls (p < 0.01) and patients with ulcerative colitis (p < 0.01). Serum-dependent phagocytosis by leukocytes from patients with Crohn's disease did not differ from that in controls but was slightly increased in patients with ulcerative colitis (p < 0.02). Unstimulated leukocytes showed increased oxidative metabolic activity in both patient groups compared with controls (p < 0.01), which was negatively correlated with the disease activity in Crohn's disease (p < 0.02). The study shows that mobilized leukocytes from patients with Crohn's disease differ from those mobilized in ulcerative colitis and supports the concept of an abnormal inflammatory reaction in Crohn's disease. 相似文献
988.
Patricia Iozzo Giuseppe RossiClaudio Michelassi Patrizia LandiClara Carpeggiani 《International journal of cardiology》2013
Background
Several epidemiological reports indicate that the body mass index (BMI) is inversely related with mortality, in spite of the notion that obesity is a recognized cardio-metabolic risk factor. The aim of the study was to evaluate the independent impact of overweight and obesity on long-term mortality in a large cohort of patients with heart disease (HD).Methods
The study included 10,446 patients hospitalized in the last three decades for ischemic (60%) or non-ischemic HD and followed-up for 10 years. The relationship between BMI and total or cardiovascular mortality was analyzed in the whole cohort, and in age-stratified categories (≤ 65 and > 65 years). Considering that survival in HD patients has improved after the introduction of revascularization, beta-blockers, ACE inhibitors, and statins, the relationship was re-examined separately in patients hospitalized before and after 1990.Results
Diabetes, hyperuricemia, hypertension, glycaemia, and triglyceridemia increased across BMI groups. During follow-up (73 ± 59 months) there were 1707 all-cause deaths (47% cardiac). Any relationship between BMI and mortality was lost in the ≤ 65 age category and in patients hospitalized before 1990, but it persisted in old patients hospitalized after 1990. Most significant independent predictors of mortality in all groups were hyperuricemia, diabetes and impaired ejection fraction.Conclusions
No independent relationship was found between BMI and mortality in subjects ≤ 65 years of age. This neutral relationship seems to be partly counteracted by treatment, particularly in old patients. A different effect of obesity onset in old vs. young age cannot be ruled out. 相似文献989.
Alterations during apoptosis lead to the activation of autoreactive T cells and the production of autoantibodies. This article discusses the pathogenic potential of cells dying in vivo, dissecting the role of signals that favor immune responses (adjuvants) and the influence of genetic backgrounds. Diverse factors determine whether apoptosis leads or not to a self-sustaining, clinically apparent autoimmune disease. The in vivo accumulation of uncleared dying cells per se is not sufficient to cause disease. However, dying cells are antigenic and their complementation with immune adjuvants causes lethal diseases in predisposed lupus-prone animals. At least some adjuvant signals directly target the function and the activation state of antigen presenting cells. Several laboratories are aggressively pursuing the molecular identification of endogenous adjuvants. Sodium monourate and the high mobility group B1 protein (HMGB1) are, among those identified so far, well known to rheumatologists. However, even the complementation of apoptotic cells with potent adjuvant signals fail to cause clinical autoimmunity in most strains: autoantibodies generated are transient, do not undergo to epitope/spreading and do not cause disease. Novel tools for drug development will derive from the molecular identification of the constraints that prevent autoimmunity in normal subjects. 相似文献
990.
Gambacciani M Monteleone P Vitale C Silvestri A Fini M Genazzani AR Rosano GM 《Maturitas》2002,43(2):117-123
OBJECTIVES: The purpose of this study was to evaluate endothelium-dependent flow-mediated dilation (FMD) in the brachial artery and the plasma levels of endothelin-1 in postmenopausal women at risk for coronary artery disease before and after treatment with both estradiol and estradiol plus dydrogesterone. METHODS: Sixteen postmenopausal women (PMW) (mean age 58+/-9 years) with more than two risk factors for coronary artery disease, were randomized to receive either oral estradiol (2 mg) for 28 days or oral estradiol (2 mg) for 14 days and oral estradiol (2 mg) and dydrogesterone (10 mg) for 14 days, in a double-blind, placebo-controlled, single cross-over study. Patients were crossed-over the complementary treatment 7 days after completing the first treatment. The study of forearm blood flow and the measurement of plasma endothelin-1 levels was carried out before and after each treatment. RESULTS: Estradiol significantly increased FMD as compared to baseline; the addition of dydrogesterone did not affect the effect of estradiol on FMD. Similarly reactive hyperemic flow increased after estradiol alone or in association with dydrogesterone compared to baseline. Plasma levels of endothelin-1 were significantly reduced by estradiol both when administered alone or in association with dydrogesterone. CONCLUSIONS: Hormone replacement therapy with estradiol and dydrogesterone improves endothelial function and reduces plasma levels of endothelin-1 in PMW at risk for coronary artery disease. 相似文献