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991.
Glycosylation is the most abundant and diverse form of post-translational modification of proteins. Two types of glycans exist in glycoproteins: N-glycans and O-glycans often coexisting in the same protein. O-glycosylation is frequently found on secreted or membrane-bound mucins whose overexpression and structure alterations are associated with many types of cancer. Mucins have several cancer-associated structures, including high levels of Lewis antigens characterized by the presence of terminal fucose. The present study deals with the identification of MR signals from N-acetylgalactosamine and from fucose in HeLa cells by detecting a low-field signal in one-dimensional (1D) spectra assigned to the NH of N-acetylgalactosamine and some cross peaks assigned to fucose in two-dimensional (2D) spectra. The increase of Golgi pH by treatment with ammonium chloride allowed the N-acetylgalactosamine signal assignment to be confirmed. Behaviour of MR peak during cell growth and comparison with studies from literature taken together made it possible to have more insight into the relationship between aberrantly processed mucin and the presence of non-processed N-acetylgalactosamine residues in HeLa cells. Fucose signals, tentatively ascribed to residues bound to galactose and to N-acetylglucosamine, are visible in both intact cell and perchloric acid spectra. Signals assigned to fucose bound to galactose are more evident in ammonium chloride-treated cells where structural changes of mucin-related Lewis antigens are expected as a result of the higher Golgi pH. A common origin for the N-acetylgalactosamine and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results. 相似文献
992.
993.
Berardi GR Rebelatto CK Tavares HF Ingberman M Shigunov P Barchiki F Aguiar AM Miyague NI Francisco JC Correa A Senegaglia AC Suss PH Moutinho JA Sotomaior VS Nakao LS Brofman PS 《Experimental and molecular pathology》2011,(2):149-156
Stem cell therapy has been considered a promise for damaged myocardial tissue. We have previously shown that S-nitroso-N-acetyl-D,L-penicillamine (SNAP) increases the expression of several muscular markers and VEGF in mesenchymal stem cells, indicating that transplantation of SNAP-treated cells could provide better functional outcomes. Here, we transplanted SNAP-treated adipose tissue-derived stem cells (ADSCs) in rat infarcted myocardium. After 30 days, we observed a significant improvement of the ejection fraction in rats that received SNAP-treated ADSCs, compared with those that received untreated cells (p = 0.008). Immunohistochemical reactions showed an increased expression of troponin T–C and von Willebrand factor, and organized vascular units in the infarcted area of tissue transplanted with treated ADSCs. SNAP exposure induced intracellular S-nitrosation, a decreased GSH/GSSG ratio, but did not increase cGMP levels. Collectively, these results indicate that SNAP alters the redox environment of ADSCs, possibly associated with a pre-differentiation state, which may improve cardiac function after transplantation. 相似文献
994.
Alessandra Jales Rustom Falahati Elisabeth Mari Erik J Stemmy Weiping Shen Cathy Southammakosane Dallen Herzog Stephan Ladisch David Leitenberg 《Immunology》2011,132(1):134-143
Tumour pathogenesis is characterized by an immunosuppressive microenvironment that limits the development of effective tumour‐specific immune responses. This is in part the result of tumour‐dependent recruitment and activation of regulatory cells, such as myeloid‐derived suppressor cells and regulatory T cells in the tumour microenvironment and draining lymph nodes. Shedding of gangliosides by tumour cells has immunomodulatory properties, suggesting that gangliosides may be a critical factor in initiating an immunosuppressive microenvironment. To better define the immunomodulatory properties of gangliosides on antigen‐specific T‐cell activation and development we have developed an in vitro system using ganglioside‐treated murine bone‐marrow‐derived dendritic cells to prime and activate antigen‐specific CD4+ T cells from AND T‐cell receptor transgenic mice. Using this system, ganglioside treatment promotes the development of a dendritic cell population characterized by decreased CD86 (B7‐2) expression, and decreased interleukin‐12 and interleukin‐6 production. When these cells are used as antigen‐presenting cells, CD4 T cells are primed to proliferate normally, but have a defect in T helper (Th) effector cell development. This defect in Th effector cell responses is associated with the development of regulatory T‐cell activity that can suppress the activation of previously primed Th effector cells in a contact‐dependent manner. In total, these data suggest that ganglioside‐exposed dendritic cells promote regulatory T‐cell activity that may have long‐lasting effects on the development of tumour‐specific immune responses. 相似文献
995.
Kramer U Rosciano A Pavlovic M Berthoud L Despland JN de Roten Y Caspar F 《Journal of clinical psychology》2011,67(10):1017-1027
Motive-Oriented Therapeutic Relationship (MOTR, also called Complementary Therapeutic Relationship) has already shown itself to be related to therapeutic outcome in several studies. The present study aims to test MOTR in a 4-session Brief Psychodynamic Intervention for patients presenting with major depressive disorder (MDD) and comorbid personality disorder (PD). In total, N = 20 patients were selected; n = 10 had MDD, n = 10 had MDD with comorbid PD. The first therapy session was videotaped and analyzed by means of Plan Analysis and the MOTR scale. Results suggest a differential effect on outcome: only the nonverbal component of MOTR is related to symptomatic change in patients presenting with MDD and comorbid PD; no such effect was found for patients with MDD alone. These results are discussed in line with the generalization and refinement of the conclusions of previous findings on the MOTR. 相似文献
996.
Alessandra Grassi Salles Paula Nunes Toledo Marcus Castro Ferreira 《Aesthetic plastic surgery》2009,33(4):582-590
Background Despite modern reanimation surgical techniques, facial paralysis presents with functional and aesthetic deficits. We evaluated
facial symmetry after treating with botulinum toxin the healthy side of the face of 25 patients with long-standing facial
paralysis who had previously been treated by surgical methods, with 6 months follow-up.
Methods Evaluation consisted of a clinical score, the two subscales of the Facial Disability Index, and surface electromyography.
The mean botulinum toxin dose was 38 ± 5 U (range = 15–69 U).
Results The clinical score showed significant reduction of asymmetry of 48.4% at 1 month and 16.8% after 6 months. The initial result
was a consequence of reduced motion on the treated side combined with better motion on the paralyzed side. At 6 months, the
treated side returned to basal scores. The residual effect seen in symmetry was due to an increase (18%) of motion in the
paralyzed side. There was a significant decrease in the action potential of muscles on the nonparalyzed side 1 month post
injection but completely reverted after 6 months. The Physical Function Index increased, but not significantly. The Social/Well-Being
Function Index showed a significant increase at 6 months compared to pretreatment.
Conclusion The proposed treatment improved facial symmetry for up to 6 months. Even after the end of the clinical effect of the drug,
the paralyzed side’s clinical score was 18% higher than pretreatment, with an increased quality of life. 相似文献
997.
998.
999.
Marcello Deriu MD Giovanni Cossu MD Andrea Molari MD Daniela Murgia MD Alessandra Mereu BS PhD Paola Ferrigno MD Davide Manca MD Paolo Contu MD PhD Maurizio Melis MD 《Movement disorders》2009,24(5):697-701
The aim of our study was to explore restless legs syndrome (RLS) frequency in multiple sclerosis (MS)‐patients and establish whether RLS could be a symptom of MS. Over a period of 1 year, we consecutively enrolled 202 MS‐patients and 212 healthy controls, matched for sex and age, in a case‐control study. All of them filled in a structured questionnaire according to IRLSSG criteria. Those patients who fit the diagnostic criteria were subsequently examined by a neurologist to verify the effective presence of RLS. A total of 91 MS‐patients (45%) responded positively to the questionnaires. The diagnosis of RLS was carried out in 29subjects (14.4%). Among the healthy controls, a definite diagnosis of RLS was achieved only in 6 subjects (2.8%). The risk of MS patients to present RLS was significantly higher (OR.5.76 P:0.00002) than the general population. None of them was affected by other medical conditions related to RLS developing. The 62 remaining patients presented numbness and weakness of the legs not suggestive of RLS. Our findings confirm a significant correlation between MS and RLS. In our opinion, MS must be definitively included among RLS causes. © 2008 Movement Disorder Society 相似文献
1000.
Elisabetta Crocetti William W. Hale Alessandra Fermani Quinten Raaijmakers Wim Meeus 《Journal of anxiety disorders》2009,23(6):824-829
In this study examination is given to the psychometric properties of the Italian version of the Screen for Child Anxiety Related Emotional Disorders (SCARED) in a large community sample of adolescents. Additionally, a comparison was made between the anxiety scores of this Italian adolescent cohort (N = 1975) and a comparative Dutch adolescent cohort (N = 1115).Findings revealed that a five-factor structure of the SCARED applied not only to the Italian adolescents from the general community, but also to boys and girls, and to early and middle adolescents. Moreover, sex and age differences on anxiety scores within the Italian sample were found to be consistent with previous studies of adolescent anxiety disorders. Finally, Italian adolescents reported higher anxiety scores than their Dutch peers.Findings of this study highlight that the SCARED is a valid screening instrument to rate anxiety symptoms of Italian adolescents. 相似文献