538 research outputs found
Remyelination of the corpus callosum by olfactory ensheathing cell in an experimental model of multiple sclerosis
Multiple Sclerosis (MS) causes loss of the myelin sheath, which leads to loss of neurons. Regeneration of myelin sheath stimulates axon regeneration and neurons� survival. In this study, olfactory ensheathing cell (OEC) transplantation is investigated to restore myelin sheath in an experimental model of MS in male mice.OECs were isolated from the olfactory mucosa of seven-day-old infant rats and cultured. Then, cells were evaluated and approved by flow cytometry by p75 and GFAP markers. A total of 32 mice (C57BL /6) were studied in four groups; 1) without any treatment (control), 2) Sham (receiving PBS), 3) MS model and 4) MS and OEC transplantation. MS was induced by adding Cuprizon in the diet of animals for six weeks. After the expiration of 20 days, histologic analysis was performed with approval of the presence of cells in the graft area and the removal of myelin and myelin regeneration with two types of luxal fast blue (LFB) staining and immunohistochemistry. The purity of the cells ensheathing the olfactory was 90. There was a significant difference in Myelin percentage of PBS and OEC recipient groups (P�0.05). MBP and PLP of the myelin sheath in the group receiving OECs were more than MS group.According to the findings, in MS model MBP and PLP of the myelin sheath is reduced. In the group receiving OECs, it was returned to a normal level significantly compared to the sham group received only PBS significant differences were observed. The OECs transplantation can improve myelin restoration. © 2015 Tehran University of Medical Sciences. All rights reserved
Analyse économique de la compétitivité de la filière tomate dans la région du Souss-Massa (Maroc)
The aim of this study is to evaluate the government’s intervention policies for greenhouse tomato production. The study is based on data collected from a sample of farmers in the Souss-Massa. The choice of the Souss-Massa region was made for several reasons, including the potential of tomato crop production, the share of the greenhouse tomato production in relation to domestic production and the existence of different segments and operators involved in the fresh tomato industry. For this study, we used the Policy Analysis Matrix (PAM) method. Analysis of data showed that tomato production in farms of Souss-Massa region is profitable. It has a comparative advantage and can generate foreign currency. This is due to the lower social costs of tradable inputs and to the fact that actors use many domestic resources in their production systems. Thus, with a Domestic Cost Resources ratio (DRC) below one, the activity is competitive and will be more competitive in case of a decline in social costs of domestic resources.
Key words: Tomato, Souss-Massa, policy analysis matrix, reference price, comparative advantageL’objectif de cette étude est l’évaluation des politiques d’intervention de l’État pour la production de la tomate sous serre. L’étude a été basée sur les données collectées auprès d’un échantillon d’agriculteurs de la zone de Souss-Massa. Le choix de la région de Souss-Massa a été fait pour plusieurs raisons, notamment, le potentiel de production des cultures sous serre, l’importance de la part de la production de la tomate sous serre par rapport à la production nationale et l’existence des différents segments et opérateurs qui interviennent dans la filière tomate. Pour cette étude, nous avons utilisé la méthode de la matrice d’analyse des politiques (MAP). L’analyse des données a montré que la production de la filière tomate dans les exploitations de la région de Souss-Massa est rentable. Elle a un avantage comparatif aux prix de référence et peut générer de la devise étrangère. Ceci s’explique par la diminution des coûts sociaux des intrants échangeables et par le fait que les acteurs utilisent beaucoup de ressources domestiques dans leurs systèmes de production. Par conséquent, avec un CRD (Coefficient de coût en Ressources Domestiques) inférieur à l’unité, l’activité est compétitive et elle sera plus compétitive en cas de régression des coûts sociaux (économiques) des ressources domestiques.
Mots clés: Tomate, Souss-Massa, matrice d’analyse des politiques, prix de référence, avantage comparati
The prognostic performance of Adjuvant! Online and Nottingham Prognostic Index in young breast cancer patients: an international multicentre hospital-based retrospective cohort study
High-Temperature Oxidation Behavior of Refractory High-Entropy Alloys : Effect of Alloy Composition
Knowledge, Practice, and Attitudes of Physicians in Low- and Middle-Income Countries on Fertility and Pregnancy-Related Issues in Young Women With Breast Cancer
PURPOSE: Fertility and pregnancy-related issues are highly relevant for young ( 64 40 years) patients with breast cancer. Limited evidence exists on knowledge, practice, and attitudes of physicians from low- and middle-income countries (LMICs) regarding these issues. METHODS: A 19-item questionnaire adapted from an international survey exploring issues about fertility preservation and pregnancy after breast cancer was sent by e-mail between November 2019 and January 2020 to physicians from LMICs involved in breast cancer care. Descriptive analyses were performed. RESULTS: A total of 288 physicians from Asia, Africa, America, and Europe completed the survey. Median age was 38 years. Responders were mainly medical oncologists (44.4%) working in an academic setting (46.9%). Among responders, 40.2% and 53.8% reported having never consulted the available international guidelines on fertility preservation and pregnancy after breast cancer, respectively. 25.0%, 19.1%, and 24.3% of responders answered to be not at all knowledgeable about embryo, oocyte, or ovarian tissue cryopreservation, respectively; 29.2%, 23.6%, and 31.3% declared that embryo, oocyte, and ovarian tissue cryopreservation were not available in their countries, respectively. 57.6% of responders disagreed or were neutral on the statement that controlled ovarian stimulation can be considered safe in patients with breast cancer. 49.7% and 58.6% of responders agreed or were neutral on the statement that pregnancy in breast cancer survivors may increase the risk of recurrence overall or only in those with hormone receptor-positive disease, respectively. CONCLUSION: This survey showed suboptimal knowledge, practice, and attitudes of physicians from LMICs on fertility preservation and pregnancy after treatment completion in young women with breast cancer. Increasing awareness and education on these aspects are needed to improve adherence to available guidelines and to promote patients' oncofertility counseling
Potency of extracts from selected Egyptian plants as inducers of the Nrf2-dependent chemopreventive enzyme NQO1
Clinical behavior and outcomes of breast cancer in young women with germline BRCA pathogenic variants
Young breast cancer (BC) patients carrying a germline BRCA pathogenic variant (mBRCA) have similar outcomes as non-carriers. However, the impact of the type of gene (BRCA1 vs. BRCA2) and hormone receptor status (positive [HR+] vs. negative [HR 12]) on clinical behavior and outcomes of mBRCA BC remains largely unknown. This is an international, multicenter, hospital-based, retrospective cohort study that included mBRCA patients diagnosed, between January 2000 and December 2012, with stage I\u2013III invasive early BC at age 6440 years. From 30 centers worldwide, 1236 young mBRCA BC patients were included. Among 808 and 428 patients with mBRCA1 or mBRCA2, 191 (23.6%) and 356 (83.2%) had HR+tumors, respectively (P < 0.001). Median follow-up was 7.9 years. Second primary BC (P = 0.009) and non-BC malignancies (P = 0.02) were more frequent among mBRCA1 patients while distant recurrences were less frequent (P = 0.02). Irrespective of hormone receptor status, mBRCA1 patients had worse disease-free survival (DFS; adjusted HR = 0.76, 95% CI = 0.60\u20130.96), with no difference in distant recurrence-free interval (DRFI) and overall survival (OS). Patients with HR+ disease had more frequent distant recurrences (P < 0.001) and less frequent second primary malignancies (BC: P = 0.005; non-BC: P = 0.18). No differences in DFS and OS were observed according to hormone receptor status, with a tendency for worse DRFI (adjusted HR = 1.39, 95% CI = 0.94\u20132.05) in patients with HR+ BC. Type of mBRCA gene and hormone receptor status strongly impact BC clinical behavior and outcomes in mBRCA young patients. These results provide important information for patients\u2019 counseling on treatment, prevention, and surveillance strategies
NANOG alone induces germ cells in primed epiblast in vitro by activation of enhancers.
Nanog, a core pluripotency factor in the inner cell mass of blastocysts, is also expressed in unipotent primordial germ cells (PGCs) in mice, where its precise role is yet unclear. We investigated this in an in vitro model, in which naive pluripotent embryonic stem (ES) cells cultured in basic fibroblast growth factor (bFGF) and activin A develop as epiblast-like cells (EpiLCs) and gain competence for a PGC-like fate. Consequently, bone morphogenetic protein 4 (BMP4), or ectopic expression of key germline transcription factors Prdm1, Prdm14 and Tfap2c, directly induce PGC-like cells (PGCLCs) in EpiLCs, but not in ES cells. Here we report an unexpected discovery that Nanog alone can induce PGCLCs in EpiLCs, independently of BMP4. We propose that after the dissolution of the naive ES-cell pluripotency network during establishment of EpiLCs, the epigenome is reset for cell fate determination. Indeed, we found genome-wide changes in NANOG-binding patterns between ES cells and EpiLCs, indicating epigenetic resetting of regulatory elements. Accordingly, we show that NANOG can bind and activate enhancers of Prdm1 and Prdm14 in EpiLCs in vitro; BLIMP1 (encoded by Prdm1) then directly induces Tfap2c. Furthermore, while SOX2 and NANOG promote the pluripotent state in ES cells, they show contrasting roles in EpiLCs, as Sox2 specifically represses PGCLC induction by Nanog. This study demonstrates a broadly applicable mechanistic principle for how cells acquire competence for cell fate determination, resulting in the context-dependent roles of key transcription factors during development.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nature1648
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