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991.
Verena Aliane Sylvie Pérez ré Nieoullon Jean-Michel Deniau Marie-Louise Kemel 《The European journal of neuroscience》2009,30(7):1269-1279
The dysfunction of basal ganglia circuits related to stereotyped motor activity was analysed using the well-established model of cocaine-induced stereotypy in the rat. We examined and compared the neurochemical and electrophysiological effects occurring in medial prefrontal and sensorimotor basal ganglia circuits of the dorsal striatum after cocaine injection in sensitized and non-sensitized rats. Acute injections of cocaine (25 mg/kg), not inducing stereotyped behaviour, affected both medial prefrontal and sensorimotor circuits in a similar way: (i) a mild and delayed increase and decrease of N-methyl-D-aspartate-evoked dopamine and acetylcholine release, respectively and (ii) a marked decrease of cortically evoked inhibition of substantia nigra pars reticulata neurons revealing an imbalance of information transmission between the direct and indirect trans-striatal pathways. In contrast, following sensitization to cocaine, a challenge injection of the same dose of cocaine, generating strong stereotyped behaviour, provoked neurochemical and electrophysiological effects only in the medial prefrontal but not in the sensorimotor circuits: (i) a strong increase of dopamine and decrease of acetylcholine release in the medial prefrontal territory of the dorsal striatum and (ii) a reduction of all inhibitory and excitatory components of the responses evoked in substantia nigra pars reticulata by medial prefrontal stimulation. Therefore, these data disclose distinct reactivity of the medial prefrontal and sensorimotor circuits of the basal ganglia to repeated cocaine administration leading to stereotyped behaviour induced by subsequent cocaine challenge. Thus, we suggest that stereotyped behaviour is correlated to an imbalance between the medial prefrontal and sensorimotor circuits of the basal ganglia resulting in a loss of control of motor behaviour. 相似文献
992.
Sarah King PhD Jo Campbell PhD Rebecca Rowe MA MCLIP Marie-Louise Daly MD George Moncrieff MD Catriona Maybury PhD 《Journal of Cosmetic Dermatology》2023,22(10):2650-2662
Background
Topical azelaic acid (AA) is indicated for acne and rosacea, but there is some evidence for its use for other dermatological conditions.Aims
To assess the effectiveness and safety of topical AA for acne vulgaris, rosacea, hyperpigmentation/melasma, and skin aging.Methods
RCTs of at least 6 weeks' treatment duration were eligible for inclusion. Databases including MEDLINE, Embase, CINAHL, and ClinicalTrials.gov were searched up to December 2022. Two reviewers were involved in all stages of the systematic review process.Results
Forty-three RCTs met the inclusion criteria. Meta-analyses within 20 rosacea studies demonstrated that erythema severity, inflammatory lesion counts, overall improvement, and treatment success (achieving skin clarity) were significantly improved with AA compared with vehicle after 12 weeks. AA was more effective than metronidazole 0.75% for improved erythema severity, overall improvement, and inflammatory lesion counts. Sixteen acne studies suggest that AA is more effective than vehicle for improving global assessments and reducing acne severity. AA 20% also significantly reduced more lesions than erythromycin gel. Within seven melasma studies, AA 20% was significantly better than vehicle for both severity and global improvement. AA 20% demonstrated significantly better results compared with hydroquinone 2% for global improvement. Very few significant differences between AA and comparators were observed for commonly reported adverse events. No eligible RCTs were found that evaluated skin aging.Conclusions
AA is more effective than vehicle for rosacea, acne and melasma. Comparisons between AA and other treatments were often equivalent. Where there is equivalence, AA may be a good option for some clinical situations. RCT evidence is needed to evaluate the effectiveness of AA on skin aging. 相似文献993.
Cheryl Zlotnick Harshida Patel Parveen Azam Ali Temitayo Odewusi Marie-Louise Luiking 《Nursing inquiry》2024,31(2):e12607
Globally, one of every eight nurses is a migrant, but few studies have focused on the healthcare experiences of migrant nurses (MNs) as consumers or recipients of healthcare. We address this gap by examining MNs and their acculturation, barriers to healthcare access, and perceptions of healthcare encounters as consumers. For this mixed-methods study, a convenience sample of MNs working in Europe and Israel was recruited. The quantitative component's methods included testing the reliability of scales contained within the questionnaire and using Hayes Process Model #4 to test for mediation. The qualitative component's methods included analyzing interviews with iterative inductive thematic analysis. Quantitative findings on MNs (n = 73) indicated that the association between acculturation and perception of the healthcare encounter, which MNs experienced as healthcare consumers, was mediated by barriers to healthcare access, even after adjusting for age and gender (p = 0.03). Qualitative interviews with MNs (n = 13) provided possible explanations for the quantitative findings. Even after working in the host country's healthcare system for several years, MNs reported difficulties with their healthcare encounters as healthcare consumers, not only due to their limited knowledge about the culture and healthcare resources but also due to the biased responses they received. 相似文献
994.
Arnoud H. A. M. van Oijen Marie-Louise Verhulst Hennie M. J. Roelofs Wilbert H. M. Peters Wink A. de Boer Jan B. M. J. Jansen 《Cancer science》2001,92(12):1329-1334
Glutathione S-transferases (GST) and glutathione peroxidases (GPO) are important in detoxification. GST activity in the mucosa of the gastrointestinal tract is inversely correlated with the development of gastrointestinal cancer. Helicobacter pylori (H. pylori) infection has been associated with gastric cancer. We studied GST activity and the substrate glutathione (GSH) in patients with H. pylori-associated gastritis. GST activity and isoenzyme levels, GPO activity and GSH levels were studied in antral biopsies of 38 H. /pyfori-positive patients, before and after eradication treatment. In 31 patients in whom H. pylori was successfully eradicated, antral GST enzyme activity before therapy was 532 (465–598) nmol/mg protein-min (mean and 95% confidence interval) and that after therapy was 759 (682–836) nmol/mg protein-min ( P <0.0001). Correspondingly, levels of GST α and GST-P1 were higher after eradication ( P <0.001). GSH concentration significantly increased: 21.2 (16.2–26.2) nmol/mg protein before and 27.1 (23.6–30.6) nmol/mg protein after therapy ( P <0.05). In 7 patients in whom H. pylori was not eradicated, GST activity was 671 (520–823) nmol/mg protein min and 599 (348–850) nmol/mg protein before and after treatment respectively ( P =0.32). GSH levels were 17.4 (9.0–25.7) nmol/mg protein and 18.2 (9.1–27.3) nmol/mg protein, respectively ( P =0.84). No differences in antral GPO enzyme activity, both of selenium (Se)-dependent and total GPO, before and after successful treatment were found. Eradication of H. pylori infection increases GST activity and GSH levels in antral mucosa. Low GST activity and GSH concentration due to H. pylori infection might play a role in gastric carcinogenesis. 相似文献
995.
Veronique Hahn Marie-Louise Hartmann Jean-Pierre Ebel Patrick Stiegler 《Molecular immunology》1987,24(12):1373-1382
Analysis of the antigenic structure of the E. coli ribosomal protein S1 was undertaken using a set of 13 monoclonal antibodies (MAbs) directed against the isolated S1. The location of the epitopes was mapped using a series of large fragments and truncated forms of S1. Most of the epitopes were localized in the C-terminal half of the molecule, while only one antibody bound to the N-terminal region. Two MAbs were able to bind to more than one region of S1, suggesting the presence of repeated epitopes related to internal sequence homologies. Six distinct antigenic domains were identified by competitive binding assays. Competition between some antibodies suggested that the C-terminal region of S1 might be in spatial proximity with the N-terminal domain in the tertiary structure of the protein. The binding of a few MAbs induced conformational changes in the protein which resulted in the complete inhibition of antibody binding at non-adjacent sites. All the MAbs reacted with the isolated form of S1 or with the protein bound to the small ribosomal subunit. This indicated that the same epitopes were expressed in the two forms of the antigen and that they were accessible to antibody binding when S1 was part of the ribosomal subunit. 相似文献
996.
Cultures of Trypanosoma cruzi have been exposed to the drugs hydroxyurea and colchicine. We found that hydroxyurea (200 microgram/ml) completely inhibited growth and differentiation of T. cruzi Y strain. Colchicine (200 microgram/ml) reduced the growth of T. cruzi 30% and stimulated cell differentiation from epimastigotes to trypomastigotes. Furthermore it caused anuclear cells with apparently intact kinetoplasts. The possible use of these anuclear forms in studies on kinetoplast DNA organization and expression is suggested. 相似文献
997.
998.
N-(4-Hydroxyphenyl)retinamide, a new retinoid for prevention of breast cancer in the rat. 总被引:1,自引:0,他引:1
R C Moon H J Thompson P J Becci C J Grubbs R J Gander D L Newton J M Smith S L Phillips W R Henderson L T Mullen C C Brown M B Sporn 《Cancer research》1979,39(4):1339-1346
The synethesis of a new retinoid, N-(4-hydroxyphenyl)-all-trans-retinamide, which has useful biological properties, is described. This retinoid was more potent than retinyl acetate in reversing keratinization caused by retinoid deficiency in tracheal organ culture. It was markedly less toxic than retinyl acetate when fed p.o. to rats over 2-week or 6-month periods. It was an effective agent for inhibition of the development of breast cancer induced in rats by N-nitroso-N-methylurea, although it was not as potent as retinyl acetate in this regard. However, the lesser toxicity of 4-hydroxyphenylretinamide makes it a superior agent for prevention of breast cancer. High-pressure liquid chromatographic analyses of liver and breast extracts from rats treated for 6 months with retinoids show the pharmacokinetic basis for the superiority of 4-hydroxyphenylretinamide; this retinoid and its metabolites were found in high concentrations in breast tissue, without any measurable accumulation in the liver or evident liver toxicity. In contrast, chronic feeding of retinyl acetate caused marked deposition of retinyl esters in the liver and severe hepatotoxicity. Whole mounts of rat mammary glands, made after chronic feeding of 4-hydroxyphenylretinamide, showed that it had a marked antiproliferative effect on mammary epithelium. 相似文献
999.
1000.
Maria-Cristina Gagliardi Roberto Nisini Rosalba Benvenuto Guido De Petrillo Marie-Louise Michel Vincenzo Barnaba 《European journal of immunology》1994,24(6):1372-1376
In a previous study, we identified that transferrin receptor (TfR) is the receptor utilized by hepatitis B virus (HBV) to enter T cells. We demonstrated that hepatitis B envelope antigen (HBenv Ag) is taken up by activated T cells via TfR, processed in endosomal compartments, and presented on class II molecules to specific CD4+ T cell clones. Herein, we report that binding to soluble ferric Tf by HBenv Ag is needed in TfR-mediated endocytosis. Accordingly, presentation of HBenvAg by activated T cells is not observed in serum-free medium and is restored by addition of soluble Tf. Moreover, we provide evidence that pre-S2 and S regions of HBenv Ag contain the critical residues for the interaction with soluble Tf. Our data not only explain HBV entry into a variety of host activated cells, but may also help in developing strategies to alter the course of chronic HBV infection. 相似文献