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991.
Effects of a single footshock followed by situational reminders on HPA axis and behaviour in the aversive context in male and female rats 总被引:2,自引:0,他引:2
Louvart H Maccari S Lesage J Léonhardt M Dickes-Coopman A Darnaudéry M 《Psychoneuroendocrinology》2006,31(1):92-99
Gender is an important factor in the vulnerability to develop psychopathologies. At the biological level, stress-related pathologies such as depression or post-traumatic stress disorder (PTSD) are associated with profound disturbances of the hypothalamo-pituitary-adrenal (HPA) axis. The aim of the present study was to assess sex-differences in the long-term effect of an intense stressful procedure on HPA function and behaviour in the aversive context in rats. Female and male rats experienced an aversive procedure consisting in an electric footshock (2mA, 10s) in a dark chamber followed by 3 weekly situational reminders (SR, 2min in the white chamber close to the footshock chamber). Our results indicate that 41 days after the end of the aversive procedure, female rats showed an increase of the corticosterone negative feedback in response to restraint stress, whereas such effect was not observed in males. Despite this change in the hormonal response, glucocorticoid receptors mRNA expression in the hippocampus was not affected in shocked females. In contrast, a significant increase of the mineralocorticoid receptors mRNA was observed in the CA2 of the hippocampus in shocked males. Finally, CRH mRNA levels in the paraventricular nucleus of the hypothalamus (PVN) were decreased in both female and male animals exposed to the aversive procedure. Behavioural observation revealed that shocked males and shocked females showed a high level of avoidance. However, the latency to visit the shock box was lower in females, which spent also more time in this area than males. In conclusion, our results suggest that gender might be a key factor impacting the direction of the effects induced by an intense stress. Interestingly, only females exhibited an increased negative feedback of the HPA axis response to stress, which could parallel endocrine changes of PTSD. 相似文献
992.
Veber D Mutti E Galmozzi E Cedrola S Galbiati S Morabito A Tredici G La Porta CA Scalabrino G 《Journal of neuroimmunology》2006,176(1-2):24-33
The levels of the soluble (s) CD40:sCD40 ligand (L) dyad, which belongs to the tumor necrosis factor (TNF)-alpha:TNF-alpha-receptor superfamily, are significantly increased in the cerebrospinal fluid (CSF), but not the serum of cobalamin (Cbl)-deficient (Cbl-D) rats. They were normalized or significantly reduced after treatment with Cbl, transforming growth factor-beta1 or S-adenosyl-L-methionine, and the normal myelin ultrastructure of the spinal cord was concomitantly restored. The concomitance of the two beneficial effects of these treatments strongly suggests that the increases in CSF sCD40:sCD40L levels may participate in the pathogenesis of purely myelinolytic Cbl-D central neuropathy in the rat. In keeping with this, an anti-CD40 treatment prevented myelin lesions. 相似文献
993.
Marchesi C De Panfilis C Cantoni A Fontò S Giannelli MR Maggini C 《Progress in neuro-psychopharmacology & biological psychiatry》2006,30(7):1240-1245
OBJECTIVE: In this naturalistic and prospective study, personality was assessed in patients with panic disorder (PD), in order to evaluate whether personality features negatively influence the outcome of pharmacological treatment. METHOD: Before drug treatment, PD was diagnosed with the Structured Clinical Interview for DSM-IV disorders and personality was assessed with the Structured Interview for DSM-IV Personality Disorders. Moreover, all patients were evaluated with the SCL-90, the Ham-A and Ham-D. Then, patients were randomly treated with paroxetine (33.5+/-13.3 mg/day) or citalopram (34.7+/-15.2 mg/day) and were followed at monthly intervals for 1 year. Absence of full and limited-symptom attacks, anticipatory anxiety, phobic avoidance and depression for 3 months was used to establish remission. The effect of personality traits on each symptom domain was evaluated. RESULTS: Seventy-one patients completed the study. Remission rate was 76% for panic attacks and 46% for complete remission. When the effects of age, gender, age of onset and duration of PD, baseline SCL-90 phobic anxiety, Ham-A and Ham-D scores, Axis I comorbidity and the SIDP traits on remission were analyzed in a logistic regression, only borderline traits negatively influenced remission of panic attacks (OR=0.69; 95% CI=0.49-0.96; p=0.03), whereas the number of traits of each personality Cluster and the total number of SIDP traits did not affect the outcome of treatment. CONCLUSIONS: This study suggests that in PD patients, borderline features may negatively influence the response to monotherapy with SSRI drugs; therefore, other treatment strategies (i.e., combination of SSRI with psychotherapy) are needed to obtain remission in these patients. 相似文献
994.
Mauro Contini Anna Apostolo Gaia Cattadori Stefania Paolillo Annamaria Iorio Erika Bertella Elisabetta Salvioni Marina Alimento Stefania Farina Pietro Palermo Monica Loguercio Valentina Mantegazza Marlus Karsten Susanna Sciomer Damiano Magrì Cesare Fiorentini Piergiuseppe Agostoni 《International journal of cardiology》2013
Background
Several β-blockers, with different pharmacological characteristics, are available for heart failure (HF) treatment. We compared Carvedilol (β1–β2–α-blocker), Bisoprolol (β1-blocker), and Nebivolol (β1-blocker, NO-releasing activity).Methods
Sixty-one moderate HF patients completed a cross-over randomized trial, receiving, for 2 months each, Carvedilol, Nebivolol, Bisoprolol (25.6 ± 12.6, 5.0 ± 2.4 and 5.0 ± 2.4 mg daily, respectively). At the end of each period, patients underwent: clinical evaluation, laboratory testing, echocardiography, spirometry (including total DLCO and membrane diffusion), O2/CO2 chemoreceptor sensitivity, constant workload, in normoxia and hypoxia (FiO2 = 16%), and maximal cardiopulmonary exercise test.Results
No significant differences were observed for clinical evaluation (NYHA classification, Minnesota questionnaire), laboratory findings (including kidney function and BNP), echocardiography, and lung mechanics. DLCO was lower on Carvedilol (18.3 ± 4.8* mL/min/mm Hg) compared to Nebivolol (19.9 ± 5.1) and Bisoprolol (20.0 ± 5.0) due to membrane diffusion 20% reduction (* = p < 0.0001). Constant workload exercise showed in hypoxia a faster VO2 kinetic and a lower ventilation with Carvedilol. Peripheral and central sensitivity to CO2 was lower in Carvedilol while response to hypoxia was higher in Bisoprolol. Ventilation efficiency (VE/VCO2 slope) was 26.9 ± 4.1* (Carvedilol), 28.8 ± 4.0 (Nebivolol), and 29.0 ± 4.4 (Bisoprolol). Peak VO2 was 15.8 ± 3.6* mL/kg/min (Carvedilol), 16.9 ± 4.1 (Nebivolol), and 16.9 ± 3.6 (Bisoprolol).Conclusions
β-Blockers differently affect several cardiopulmonary functions. Lung diffusion and exercise performance, the former likely due to lower interference with β2-mediated alveolar fluid clearance, were higher in Nebivolol and Bisoprolol. On the other hand, Carvedilol allowed a better ventilation efficiency during exercise, likely via a different chemoreceptor modulation. Results from this study represent the basis for identifying the best match between a specific β-blocker and a specific HF patient. 相似文献995.
Gabrio Bassotti Vincenzo Villanacci Riccardo Nascimbeni Elisabetta Antonelli Moris Cadei Stefania Manenti Luisa Lorenzi Amin Titi Bruno Salerni 《International journal of colorectal disease》2013,28(2):267-272
Background
Gut mast cells represent an important cell population involved in intestinal homeostasis and inflammatory processes. However, their possible role has not to date been investigated in colonic diverticular disease.Aims
This study aims to evaluate colonic mast cells in patients undergoing surgery for diverticular disease.Methods
Surgical resection samples from 27 patients undergoing surgery for diverticular disease (12 emergency procedures for severe disease and 15 elective procedures) were evaluated. The number of mast cells was assessed in the various layers by means of a specific antibody (tryptase) and compared with those evaluated in ten controls. In patients with mast cells degranulation, double immunohistochemistry, also assessing nerve fibres, was carried out. In addition, the presence of myenteric plexitis was sought.Results
Compared with controls, the number of mast cells in diverticular patients was significantly increased, both as an overall figure and in the various layers of the large bowel. In patients in whom mast cells degranulation was present, these were always closed to nerve fibres. No differences were found between the two subgroups of patients with respect to the number and distribution of mast cells; however, all patients undergoing emergency surgery (but none of those undergoing elective procedures) had myenteric plexitis, represented by lymphocytic infiltration in 67 % and eosinophilic infiltration in 33 % of cases.Conclusions
Patients with diverticular disease display an increase of mast cells in the large bowel. The presence of myenteric plexitis in those with complicated, severe disease, suggest that this could represent a histopathologic marker of more aggressive disease. 相似文献996.
Vincenzo Solfrizzi Emanuele Scafato Vincenza Frisardi Davide Seripa Giancarlo Logroscino Patrick G. Kehoe Bruno P. Imbimbo Marzia Baldereschi Gaetano Crepaldi Antonio Di Carlo Lucia Galluzzo Claudia Gandin Domenico Inzitari Stefania Maggi Alberto Pilotto Francesco Panza 《Age (Dordrecht, Netherlands)》2013,35(2):441-453
Midlife elevated blood pressure and hypertension contribute to the development of Alzheimer's disease (AD) and overall dementia. We sought to estimate whether angiotensin-converting enzyme inhibitors (ACE-Is) reduced the risk of developing mild cognitive impairment (MCI) in cognitively normal individuals. In the Italian Longitudinal Study on Aging, we evaluated 1,445 cognitively normal individuals treated for hypertension but without congestive heart failure from a population-based sample from eight Italian municipalities with a 3.5-year follow-up. MCI was diagnosed with current clinical criteria. Dementia, AD, and vascular dementia were diagnosed based on DSM-IIIR criteria, NINCDS–ADRDA criteria, and ICD-10 codes. Among 873 hypertension-treated cognitively normal subjects, there was no significant association between continuous exposure to all ACE-Is and risk of incident MCI compared with other antihypertensive drugs [hazard ratio (HR), 0.45, 95% confidence interval (CI), 0.16–1.28]. Captopril exposure alone did not significantly modify the risk of incident MCI (HR, 1.80, 95% CI, 0.39–8.37). However, the enalapril sub-group alone (HR, 0.17, 95% CI, 0.04 –0.84) or combined with the lisinopril sub-group (HR, 0.27, 95% CI, 0.08–0.96), another ACE-I structurally related to enalapril and with similar potency, were associated with a reduced risk of incident MCI. Study duration exposure to ACE-Is as a “class” was not associated with incident MCI in older hypertensive adults. However, within-class differences linked to different chemical structures and/or drug potencies may exist, with a possible effect of the enalapril and lisinopril sub-groups in reducing the risk of incident MCI. 相似文献
997.
Endothelial cell binding by systemic lupus antibodies: functional properties and relationship with anti-DNA activity 总被引:3,自引:0,他引:3
Moscato S Pratesi F Bongiorni F Scavuzzo MC Chimenti D Bombardieri S Migliorini P 《Journal of autoimmunity》2002,18(3):231-238
Anti-DNA antibodies and anti-endothelial cell antibodies (AECA) are often detected in systemic lupus erythematosus (SLE). Anti-DNA antibodies can also bind the membrane of human umbilical vein endothelial cells (HUVEC), but little is known about the presence of AECA in the population of immunoglobulins from SLE sera that do not bind DNA. The aim of this study is to analyse the ability of anti-DNA and non-anti-DNA antibodies from SLE sera to bind endothelial cell antigens and to investigate their pathogenic potential. Both anti-DNA and non-anti-DNA antibodies display AECA activity by immunoprecipitation and flow cytometry and in some patients recognize antigens of identical molecular weight. Complement-dependent cytotoxicity on HUVEC was not detected with either anti-DNA or non-anti-DNA antibodies. Similarly, apoptosis was not induced in HUVEC and HL60 incubated with anti-DNA or non-anti-DNA antibodies, as shown by the DNA hypodiploid content. These data indicate that AECA are highly heterogeneous, as they recognize a wide variety of surface molecules on HUVEC and equally present in anti-DNA and non-anti-DNA antibodies from SLE patients. 相似文献
998.
Mariana Fernandes Inês C. Gonçalves Stefania Nardecchia Isabel F. Amaral Mário A. Barbosa M. Cristina L. Martins 《International journal of pharmaceutics》2013
Chitosan microspheres have been explored for pharmaceutical applications, namely as a drug delivery systems for Helicobacter pylori gastric infection treatment, due to their mucoadhesive capacity. In this study, a different application of chitosan microspheres is proposed aiming the creation of an H. pylori-binding system where, after oral administration, microspheres will capture and remove these bacteria from infected patients, taking advantage of their muco/bacterial adhesive process. However, mucoadhesion is influenced by the degree of crosslinking necessary to avoid microspheres dissolution in the acidic gastric environment. 相似文献
999.
Stefania Mazzitelli Cinzia Pagano Danilo Giusepponi Claudio Nastruzzi Luana Perioli 《International journal of pharmaceutics》2013
The effect of different preparation parameters were analyzed with respect to the rheological and pharmaceutical characteristics of hydrogel blend patches, as transdermal delivery formulation. Mixtures of pectin and gelatin were employed for the production of patches, with adjustable properties, following a two-step gelation procedure. The first gelation, a thermal one, is trigged by the presence of gelatin, whereas, the second gelation, an ionic one, is due to the formation of the typical egg box structure of pectin. In particular, the patch structural properties were assessed by oscillation stress sweep measurements which provided information concerning their viscolelastic properties. In addition, different modalities for drug loading were analyzed with respect to drug homogeneous distribution; testosterone was employed as model drug for transdermal administration. Finally, the performances of the produced transdermal patches were studied, in term of reproducibility and reliability, by determination of in vitro drug release profiles. 相似文献
1000.
Angelo Blasio Attilio Iemolo Valentina Sabino Stefania Petrosino Luca Steardo Kenner C Rice Pierangelo Orlando Fabio Arturo Iannotti Vincenzo Di Marzo Eric P Zorrilla Pietro Cottone 《Neuropsychopharmacology》2013,38(12):2498-2507
The anti-obesity medication rimonabant, an antagonist of cannabinoid type-1 (CB1) receptor, was withdrawn from the market because of adverse psychiatric side effects, including a negative affective state. We investigated whether rimonabant precipitates a negative emotional state in rats withdrawn from palatable food cycling. The effects of systemic administration of rimonabant on anxiety-like behavior, food intake, body weight, and adrenocortical activation were assessed in female rats during withdrawal from chronic palatable diet cycling. The levels of the endocannabinoids, anandamide and 2-arachidonoylglycerol (2-AG), and the CB1 receptor mRNA and the protein in the central nucleus of the amygdala (CeA) were also investigated. Finally, the effects of microinfusion of rimonabant in the CeA on anxiety-like behavior, and food intake were assessed. Systemic administration of rimonabant precipitated anxiety-like behavior and anorexia of the regular chow diet in rats withdrawn from palatable diet cycling, independently from the degree of adrenocortical activation. These behavioral observations were accompanied by increased 2-AG, CB1 receptor mRNA, and protein levels selectively in the CeA. Finally, rimonabant, microinfused directly into the CeA, precipitated anxiety-like behavior and anorexia. Our data show that (i) the 2-AG-CB1 receptor system within the CeA is recruited during abstinence from palatable diet cycling as a compensatory mechanism to dampen anxiety, and (ii) rimonabant precipitates a negative emotional state by blocking the beneficial heightened 2-AG-CB1 receptor signaling in this brain area. These findings help elucidate the link between compulsive eating and anxiety, and it will be valuable to develop better pharmacological treatments for eating disorders and obesity. 相似文献