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排序方式: 共有1546条查询结果,搜索用时 15 毫秒
941.
Di Ianni M Del Papa B Zei T Iacucci Ostini R Cecchini D Cantelmi MG Baldoni S Sportoletti P Cavalli L Carotti A Pierini A Falini B Martelli MF Falzetti F 《Transfusion and apheresis science》2012,47(2):213-216
We selected T regulatory cells (Tregs) from standard leukapheresis using double-negative selection (anti-CD8 and anti-CD19) followed by positive selection (anti-CD25) and 72 procedures were performed. A median of 263×10(6)cells (range 143-470×10(6)) were recovered with a mean of CD4(+)/CD25(+) cells of 94.5±2.4% (36.5±18.6% CD4(+)/CD25(+hi)). FoxP3(+) cells were equal to 79.8%±22.2. CD127(+) cells were 12.5%±8.2. The inhibition assay showed an inhibition rate of 67±22. Cells isolated by means of this approach can be used in allogeneic hematopoietic stem cell transplantation to reduce the incidence and severity of GvHD without bystander inhibition of general immunity. 相似文献
942.
An abundance of animal research suggests that fear inhibits pain whereas anxiety increases it. Human studies on this topic are more scarce, and the existing evidence seems rather inconsistent. Therefore, we aimed to investigate the divergent effects of both negative emotional states-that is, pain-related fear and anxiety on pain sensitivity and unpleasantness. Possible sex-related differences were also under investigation, as well as the potential mediational role of fear of movement-related pain on the differences in pain intensity and unpleasantness between both sexes. We employed a voluntary joystick movement paradigm using movements as conditioned stimuli (CSs) and a painful electrocutaneous stimulus as the unconditioned stimulus. Healthy participants received predictable shocks in one condition and unpredictable shocks in another condition. The former procedure is known to induce fear of movement-related pain to the CS+ movement (movement consistently followed by pain), whereas the latter procedure induces (contextual) pain-related anxiety. Results showed that fear of movement-related pain indeed resulted in decreased pain intensity/unpleasantness ratings, while pain-related anxiety led to increased pain intensity/unpleasantness reports. Further, the anticipated sex difference was modulated by time. That is, women gradually reported more pain/unpleasantness, whereas men do not show such a sensitization effect. Moreover, this sex-specific sensitization is partially mediated by (conditioned) fear of movement-related pain. Women also report increasingly more fear of pain over conditioning blocks, while men do not. These results might be interesting in the light of the overrepresentation of women in a number of clinical pain conditions as well as anxiety disorders. 相似文献
943.
Foti F Laricchiuta D Cutuli D De Bartolo P Gelfo F Angelucci F Petrosini L 《Cerebellum (London, England)》2011,10(1):104-119
The exposure to enriched environments allows the maintenance of normal cognitive functioning even in the presence of brain
pathology. Up until now, clinical and experimental studies have investigated environmental effects mainly on the symptoms
linked to the presence of neuro-degenerative diseases, and no study has yet analyzed whether prolonged exposure to complex
environments allows modifying the clinical expression and compensation of deficits of cerebellar origin. In animals previously
exposed to complex stimulations, the effects of cerebellar lesions have been analyzed to verify whether a prolonged and intense
exposure to complex stimulations affected the compensation of motor and cognitive functions following a cerebellar lesion.
Hemicerebellectomized or intact animals housed in enriched or standard conditions were administered spatial tests. Postural
asymmetries and motor behavior were also assessed. Exposure to the enriched environment almost completely compensated the
effects of the hemicerebellectomy. In fact, the motor and cognitive performances of the enriched hemicerebellectomized animals
were similar to those of the intact animals. The plastic changes induced by enhanced mental and physical activity seem to
provide the development of compensatory responses against the disrupting motor and cognitive consequences of the cerebellar
damage. 相似文献
944.
945.
Moreno LZ Paixão R Gobbi DD Raimundo DC Ferreira TP Hofer E Matte MH Moreno AM 《Research in microbiology》2012,163(4):268-271
Atypical Listeria innocua strains presenting phenotypic characteristics similar to those of Listeria monocytogenes were recently isolated from food and the environment. These isolates also tested positive for virulence genes specific to L. monocytogenes. Here we report the isolation of atypical hemolytic L. innocua strains from the environment of pork processing plants in Brazil. The strains were positive for L. monocytogenes virulence genes hly, inlA and inlB by PCR and presented genotypic similarities with human isolates of L. monocytogenes via the AFLP technique using HindIII single enzyme protocol. Phenotypic and genotypic similarities suggest that these atypical L. innocua may be pathogenic strains. 相似文献
946.
Alexandre A. Vieira Laurival A. De Luca JrEduardo Colombari Debora S.A. ColombariJosé V. Menani 《Neuroscience letters》2012
Electrolytic lesions of the commissural nucleus of the solitary tract (commNTS) in rats enhance the pressor response to bilateral carotid occlusion or to intravenous infusion of hypertonic NaCl without changing baroreflex responses. In an opposite direction, commNTS lesions abolish the pressor responses to peripheral chemoreflex activation. These opposite effects of commNTS lesions apparently result from an impairment of sympathetic activation in one case and in a facilitation of vasopressin secretion in the others. In the present study, we investigated the effects of the electrolytic lesions of the commNTS in the pressor responses that depend on sympathetic activation and vasopressin secretion produced by central cholinergic or adrenergic activation with intracerebroventricular (i.c.v.) injections of carbachol or noradrenaline, respectively, in unanesthetized rats. Male Holtzman rats (280–320 g, n = 8–15/group) with acute (1 day) or chronic (21 days) sham or commNTS lesions (1 mA × 10 s) and a stainless steel cannula implanted in the lateral ventricle were used. Acute commNTS lesions increased the pressor response to i.c.v. injection of carbachol (0.5 nmol/1 μ1) (52 ± 2, vs. sham: 37 ± 2 mmHg) or noradrenaline (80 nmol/1 μl) (45 ± 6, vs. sham: 30 ± 3 mmHg), whereas chronic commNTS lesions did not affect the pressor responses to the same treatments. Lesions of the commNTS impaired chemoreflex responses produced by intravenous KCN, without changing baroreflex responses. The results suggest that commNTS-dependent inhibitory signals are involved in the modulation of the pressor responses to central cholinergic and adrenergic activation, probably limiting vasopressin secretion. 相似文献
947.
Ochoa-Sanchez R Comai S Lacoste B Bambico FR Dominguez-Lopez S Spadoni G Rivara S Bedini A Angeloni D Fraschini F Mor M Tarzia G Descarries L Gobbi G 《The Journal of neuroscience》2011,31(50):18439-18452
Melatonin activates two brain G-protein coupled receptors, MT(1) and MT(2), whose differential roles in the sleep-wake cycle remain to be defined. The novel MT(2) receptor partial agonist, N-{2-[(3-methoxyphenyl) phenylamino] ethyl} acetamide (UCM765), is here shown to selectively promote non-rapid eye movement sleep (NREMS) in rats and mice. The enhancement of NREMS by UCM765 is nullified by the pharmacological blockade or genetic deletion of MT(2) receptors. MT(2), but not MT(1), knock-out mice show a decrease in NREMS compared to the wild strain. Immunohistochemical labeling reveals that MT(2) receptors are localized in sleep-related brain regions, and notably the reticular thalamic nucleus (Rt). Microinfusion of UCM765 in the Rt promotes NREMS, and its systemic administration induces an increase in firing and rhythmic burst activity of Rt neurons, which is blocked by the MT(2) antagonist 4-phenyl-2-propionamidotetralin. Since developing hypnotics that increase NREMS without altering sleep architecture remains a medical challenge, MT(2) receptors may represent a novel target for the treatment of sleep disorders. 相似文献
948.
Muraro E Martorelli D Turchet E Miolo G Scalone S Comaro E Talamini R Mastorci K Lombardi D Perin T Carbone A Veronesi A Crivellari D Dolcetti R 《Breast cancer research : BCR》2011,13(6):R117-13
Introduction
The clinical efficacy of trastuzumab and taxanes is at least partly related to their ability to mediate or promote antitumor immune responses. On these grounds, a careful analysis of basal immune profile may be capital to dissect the heterogeneity of clinical responses to these drugs in patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy.Methods
Blood samples were collected from 61 locally advanced breast cancers (36 HER2- and 25 HER2+) at diagnosis and from 23 healthy women. Immunophenotypic profiling of circulating and intratumor immune cells, including regulatory T (Treg) cells, was assessed by flow cytometry and immunohistochemistry, respectively. Serum levels of 10 different cytokines were assessed by multiplex immunoassays. CD8+ T cell responses to multiple tumor-associated antigens (TAA) were evaluated by IFN-γ-enzyme-linked immunosorbent spot (ELISPOT). The Student's t test for two tailed distributions and the Wilcoxon two-sample test were used for the statistical analysis of the data.Results
The proportion of circulating immune effectors was similar in HER2+ patients and healthy donors, whereas higher percentages of natural killer and Treg cells and a lower CD4+/CD8+ T cell ratio (with a prevalence of naïve and central memory CD8+ T cells) were observed in HER2- cases. Higher numbers of circulating CD8+ T cells specific for several HLA-A*0201-restricted TAA-derived peptides were observed in HER2+ cases, together with a higher prevalence of intratumor CD8+ T cells. Serum cytokine profile of HER2+ patients was similar to that of controls, whereas HER2- cases showed significantly lower cytokine amounts compared to healthy women (IL-2, IL-8, IL-6) and HER2+ cases (IL-2, IL-1β, IL-8, IL-6, IL-10).Conclusions
Compared to HER2- cases, patients with HER2-overexpressing locally advanced breast cancer show a more limited tumor-related immune suppression. This may account for the clinical benefit achieved in this subset of patients with the use of drugs acting through, but also promoting, immune-mediated effects. 相似文献949.
Loi S Symmans WF Bartlett JM Fumagalli D Van't Veer L Forbes JF Bedard P Denkert C Zujewski J Viale G Pusztai L Esserman LJ Leyland-Jones BR 《The lancet oncology》2011,12(12):1162-1168
In this Personal View, we outline proposals for uniform collection of biospecimens obtained in neoadjuvant breast cancer trials undertaken by the Breast International Group (BIG) and the National Cancer Institute-sponsored North American Breast Cancer Group (NABCG). These proposals aim to standardise collection of high-quality specimens, with respect to both type and timing, to enhance and allow integration of results obtained from neoadjuvant trials done by several groups. They should be considered in parallel with recommendations for tissue-specimen collection and handling previously developed by BIG and NABCG. We propose that tumour tissue (formalin-fixed, paraffin-embedded and samples dedicated for molecular studies) should be taken at baseline, 1-3 weeks after the start of treatment, and at definitive surgery, with clear prioritisation in the study protocol of number, order, and preservation of samples to be gathered. This step should be accompanied by blood collection (plasma, serum, and whole blood) whenever possible. We advocate strongly a move towards one diagnostic and research biopsy procedure in all women with breast cancers potentially suitable for neoadjuvant treatment. If possible, patients should be referred at the outset to specialised centres to give them the opportunity to participate in neoadjuvant clinical trials, thereby avoiding several biopsy procedures. 相似文献
950.
Davide Serrano Matteo Lazzeroni Sara Gandini Debora Macis Harriet Johansson Jennifer Gjerde Ernst Lien Irene Feroce Giancarlo Pruneri Maria Teresa Sandri Fabio Bassi Fabricio Brenelli Alberto Luini Massimiliano Cazzaniga Clara Varricchio Aliana Guerrieri-Gonzaga Andrea DeCensi Bernardo Bonanni 《Breast cancer research : BCR》2013,15(3):R47