Test d’ajustement des copules paramétriques

Les tests d’ajustement des copules paramétriques représentent un objet très vaste et important. Dans ce mémoire de magistère on a présenté quelques approches de test d’ajustement de copules avec les méthodes qui nous permettent d’estimer les paramètres de copules. Dans l’application on a utilisé la statistique de Cramer-Von Mises qui dépend de la fonction de dépendance empirique sur quelque copules, telle que la copule de gausse, la copule de Frank et les copules de Gumbel et Clayton

Fucosyltransferase 1 and 2 play pivotal roles in breast cancer cells.

FUT1 and FUT2 encode alpha 1, 2-fucosyltransferases which catalyze the addition of alpha 1, 2-linked fucose to glycans. Glycan products of FUT1 and FUT2, such as Globo H and Lewis Y, are highly expressed on malignant tissues, including breast cancer. Herein, we investigated the roles of FUT1 and FUT2 in breast cancer. Silencing of FUT1 or FUT2 by shRNAs inhibited cell proliferation in vitro and tumorigenicity in mice. This was associated with diminished properties of cancer stem cell (CSC), including mammosphere formation and CSC marker both in vitro and in xenografts. Silencing of FUT2, but not FUT1, significantly changed the cuboidal morphology to dense clusters of small and round cells with reduced adhesion to polystyrene and extracellular matrix, including laminin, fibronectin and collagen. Silencing of FUT1 or FUT2 suppressed cell migration in wound healing assay, whereas FUT1 and FUT2 overexpression increased cell migration and invasion in vitro and metastasis of breast cancer in vivo. A decrease in mesenchymal like markers such as fibronectin, vimentin, and twist, along with increased epithelial like marker, E-cadherin, was observed upon FUT1/2 knockdown, while the opposite was noted by overexpression of FUT1 or FUT2. As expected, FUT1 or FUT2 knockdown reduced Globo H, whereas FUT1 or FUT2 overexpression showed contrary effects. Exogenous addition of Globo H-ceramide reversed the suppression of cell migration by FUT1 knockdown but not the inhibition of cell adhesion by FUT2 silencing, suggesting that at least part of the effects of FUT1/2 knockdown were mediated by Globo H. Our results imply that FUT1 and FUT2 play important roles in regulating growth, adhesion, migration and CSC properties of breast cancer, and may serve as therapeutic targets for breast cancer

Influence of Personality Types and Socio-Demographic Characteristics of Work-Study Students at a Private University, Southwest Nigeria

This study examined the influence of personality types and socio-demographic characteristics on work-study of students at Covenant University, Ota. The study used questionnaires to collect information from 100 students who participated in the programme in 2014/2015 academic session. The chi-x2 result of 12.30 for the variable responses showed that the age and the sex of students influenced their participation in work study programme with chi-x2 (29.80), degree of freedom 4 and significance level of 1 % of the combined result respectively. The finding of investigation also show that birth order influenced students participation in work study initiative with chi-x2 distribution of 19.70, degree of freedom of 4 and asymptotic significance of 1 %. Also, the result of the T-statistics (28.23) with the degree of freedom 99 revealed significance among the Personality Type “A” and “B” compositions at 1% level of significance. The estimated correlation coefficient indicates a significant strong correlation (0.630) between the response variables “Personality Type” and influence on student participation in work study programme

FAM129B, an antioxidative protein, reduces chemosensitivity by competing with Nrf2 for Keap1 binding.

BackgroundThe transcription factor Nrf2 is a master regulator of antioxidant response. While Nrf2 activation may counter increasing oxidative stress in aging, its activation in cancer can promote cancer progression and metastasis, and confer resistance to chemotherapy and radiotherapy. Thus, Nrf2 has been considered as a key pharmacological target. Unfortunately, there are no specific Nrf2 inhibitors for therapeutic application. Moreover, high Nrf2 activity in many tumors without Keap1 or Nrf2 mutations suggests that alternative mechanisms of Nrf2 regulation exist.MethodsInteraction of FAM129B with Keap1 is demonstrated by immunofluorescence, colocalization, co-immunoprecipitation and mammalian two-hybrid assay. Antioxidative function of FAM129B is analyzed by measuring ROS levels with DCF/flow cytometry, Nrf2 activation using luciferase reporter assay and determination of downstream gene expression by qPCR and wester blotting. Impact of FAM129B on in vivo chemosensitivity is examined in mice bearing breast and colon cancer xenografts. The clinical relevance of FAM129B is assessed by qPCR in breast cancer samples and data mining of publicly available databases.FindingsWe have demonstrated that FAM129B in cancer promotes Nrf2 activity by reducing its ubiquitination through competition with Nrf2 for Keap1 binding via its DLG and ETGE motifs. In addition, FAM129B reduces chemosensitivity by augmenting Nrf2 antioxidative signaling and confers poor prognosis in breast and lung cancer.InterpretationThese findings demonstrate the important role of FAM129B in Nrf2 activation and antioxidative response, and identify FMA129B as a potential therapeutic target. FUND: The Chang Gung Medical Foundation (Taiwan) and the Ministry of Science and Technology (Taiwan)

GPER-induced signaling is essential for the survival of breast cancer stem cells.

G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER- /PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs

FISH FARMING PROJECTS AROUND THE WORLD: A PRESENTATION OF SELECTED STATISTICS FROM THE FOOD AND AGRICULTURE ORGANISATION (FAO), 2022 REPORT

This paper aims to shed light on one of the most significant food-related projects: fish farming. Its importance is evident both at the individual level, by providing high nutritional value, and at the national level, through its contribution to economic and social development (food security, self-sufficiency, etc.). It also offers profitability for institutions operating within a market that is flourishing daily. The Food and Agriculture Organisation (FAO) has emphasised the importance of investing in this sector. Accordingly, this paper presents key statistics from the FAO's 2022 report. The findings indicate that fish farming production reached an estimated 120 million tonnes in 2020, a remarkable increase considering that the activity was once marginal and only began to develop from 1985 onwards. China leads in global production, accounting for more than 50%. Regionally, Asia ranks first in terms of global output, followed by Africa and Europe. Egypt is Africa's largest fish farming producer, contributing approximately 3% of global production. It is hoped that Algeria will increase its investment in this sector to achieve food security, particularly given its vast potential and capacity to take a leading position

Risks of corruption to development

The mechanisms of globalization have produced the tools, means and technological innovations that facilitated the forms of corruption, and what it also entails from the increased movement of economic activity and financial openness globally and locally, and the tendency to liberalize foreign and internal trade, and the related developments, which contributed to alleviating administrative and financial restrictions, and creating Damage to the economic structure of the state through wasting economic resources, increasing burdens on the public budget, reducing the efficiency of economic performance, or misdistributing resources, with the intent of achieving personal benefits, material or non-material, whether in kind or monetary, at the expense of the public interest. Opening channels to the emergence of many forms and forms of corruption, and thus the increased possibility of the spread of new forms of corruption, the most important of which is economic corruption. All this has led to the need for an international defense strategy against the forms and methods of corruption in institutions in general and banking in particular, linking international cooperation and regional and local coordination between the various concerned bodies economically, securely and politically, and declaring a real state of war waged by the regulatory and supervisory bodies in different countries, as well as entities The organization of development projects based on financing and lending from banking institutions in all its forms and forms against practices and forms of corruption in them

Sialylation of vasorin by ST3Gal1 facilitates TGF-β1-mediated tumor angiogenesis and progression.

ST3Gal1 is a key sialyltransferase which adds α2,3-linked sialic acid to substrates and generates core 1 O-glycan structure. Upregulation of ST3Gal1 has been associated with worse prognosis of breast cancer patients. However, the protein substrates of ST3Gal1 implicated in tumor progression remain elusive. In our study, we demonstrated that ST3GAL1-silencing significantly reduced tumor growth along with a notable decrease in vascularity of MCF7 xenograft tumors. We identified vasorin (VASN) which was shown to bind TGF-β1, as a potential candidate that links ST3Gal1 to angiogenesis. LC-MS/MS analysis of VASN secreted from MCF7, revealed that more than 80% of its O-glycans are sialyl-3T and disialyl-T. ST3GAL1-silencing or desialylation of VASN by neuraminidase enhanced its binding to TGF-β1 by 2- to 3-fold and thereby dampening TGF-β1 signaling and angiogenesis, as indicated by impaired tube formation of HUVECs, suppressed angiogenesis gene expression and reduced activation of Smad2 and Smad3 in HUVEC cells. Examination of 114 fresh primary breast cancer and their adjacent normal tissues showed that the expression levels of ST3Gal1 and TGFB1 were high in tumor part and the expression of two genes was positively correlated. Kaplan Meier survival analysis showed a significantly shorter relapse-free survival for those with lower expression VASN, notably, the combination of low VASN with high ST3GAL1 yielded even higher risk of recurrence (p = 0.025, HR = 2.967, 95% CI = 1.14-7.67). Since TGF-β1 is known to transcriptionally activate ST3Gal1, our findings illustrated a feedback regulatory loop in which TGF-β1 upregulates ST3Gal1 to circumvent the negative impact of VASN