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Plants are an important source of pharmacologically active compounds. In the present work, we characterize the impact of black cumin ( Nigella sativa L.) aqueous extracts on a yeast model of p53-dependent apoptosis. To this end, the Saccharomyces cerevisiae recombinant strain over-expressing p53 was used. The over-expression of p53 triggers the expression of apoptotic markers: the externalization of phosphatidylserine, mitochondrial defect associated with cytochrome-c release and the induction of DNA strand breaks. These different effects were attenuated by Nigella sativa L. aqueous extracts, whereas these extracts have no effect on the level of p53 expression. Thus, we focus on the anti-apoptotic molecules present in the aqueous extract of Nigella sativa L. These extracts were purified and characterized by complementary chromatographic methods. Specific fluorescent probes were used to determine the effect of the extracts on yeast apoptosis. Yeast cells over-expressing p53 decrease in relative size and have lower mitochondrial content. The decrease in cell size was proportional to the decrease in mitochondrial content and of mitochondrial membrane potential (ΔΨm). These effects were prevented by the purified aqueous fraction obtained by fractionation with different columns, named C4 fraction. Yeast cell death was also characterized by reactive oxygen species (ROS) overproduction. In the presence of the C4 fraction, ROS overproduction was strongly reduced. We also noted that the C4 fraction promotes the cell growth of control yeast cells, which do not express p53, supporting the fact that this purified extract acts on cellular mediators activating cell proliferation independently of p53. Altogether, our data obtained on yeast cells over-expressing p53 demonstrate that anti-apoptotic molecules targeting p53-induced apoptosis associated with mitochondrial dysfunction and ROS overproduction are present in the aqueous extracts of Nigella seeds and in the purified aqueous C4 fraction.

Background: The P-glycoprotein (P-gp) is one of the mechanisms of Imatinib (IM) resistance in chronic myeloid leukemia (CML). P-gp has been identified as an efflux pump involved in releasing of IM outside CML cells. To date, the P-gp involvement in the IM resistance development was not completely understood. Therefore, the present study aimed at measuring the P-gp expression level on lymphocytes from Tunisian patients with CML and correlating this level with a molecular response to IM., Method: The expression of P-gp on peripheral blood lymphocytes from 59 Tunisian patients with CML (27 IM responder patients vs 32 IM non-responder patients) was evaluated by flow cytometry., Result: Our finding showed significantly positive expression of P-gp in the lymphocytes from the IM non-responder group when compared to the IM-responder group (P = .001). In IM non-responder CML patients, the comparison between CCyR achievers and non-achievers showed a high mean fluorescence intensity (MFI) of P-gp expression in patients who did not achieve their CCyR (P = .001). The comparison between patients with primary and secondary resistance to IM showed an increasing MFI value in patients with primary resistance to IM (P = .001). Besides, the comparison between nilotinib-treated and dasatinib-treated patients proved a high value of MFI in nilotinib-treated patients (P = .001)., Conclusion: The overexpression of P-gp on lymphocytes has significantly correlated with the failed molecular response to IM in patients with CML., (© 2020 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals LLC.)

Aims: To determine region-specific reference ranges of lymphocyte T subsets in blood donors and to assess the influence of gender and age on lymphocyte T susbsets., Methods: Blood samples from 143 blood donors were collected in the Blood Transfusion Center of Sfax. Lymphocyte T subsets were analyzed using a dual-platform method with a flow cytometer (percentages) and an automated hematology analyzer (white blood cells and lymphocytes). ANOVA and Student's tests were used for data analysis., Results: Reference values were expressed as mean and 95% confidence intervals for T cells: CD3+: 1415 ± 348 cells/μL [1357-1473], CD3+/CD4+: 786 ± 220 cells/μL [732.31-811.7], CD3+/CD8+: 639 ± 258 cells/μL [596-862] and CD4+/CD8+ ratio was 1.46 ± 0.77 [1.36-1.62]. Gender and age influenced blood lymphocyte T subsets., Conclusion: Our study leads to the establishment of peripheral blood lymphocyte T subset reference ranges in blood donors in the region of Sfax. A study on a more diversified population, including more important number of individuals from various regions of Tunisia and including enumeration of other lymphocyte subsets (B cells and NK cells) is required.

The aim of the study was to evaluate the antioxidant potential of hydroxytyrosol (HT) on human sperm quality during incubation in vitro. Semen samples collected from men attending the Laboratory of Histology-Embryology of Sfax Faculty of Medicine (Tunisia) for infertility investigations were evaluated for initial sperm parameters. Only normal selected ejaculates (n = 15) were centrifuged and incubated further with or without HT (200ug ml -1 ) at room temperature for 45 min. After incubation, sperm motility and viability, DNA oxidation and reactive oxygen species (ROS) production were assessed. The results showed that centrifugation significantly influenced sperm motility and viability. The supplementation of HT in incubating media improved (P = 0.01) significantly sperm viability and decreased sperm DNA oxidation (P < 0.001) and ROS levels (P = 0.03) following centrifugation. It can be concluded that supplementation of HT might be helpful to maintain the human spermatozoon after centrifugation., (© 2016 Blackwell Verlag GmbH.)

Alloimmunization against high-frequency erythrocyte antigens is a problematic situation in terms of laboratory diagnosis, transfusion and obstetrical management. We report the case of a pregnant woman alloimmunized against public Ag. We detail the difficulties of alloantibody (Ab) identification and transfusion management of the deliveries. A 29-year-old pregnant woman was hospitalized in gynecology and obstetrics departments at 36 weeks of gestation for assessment of hydrops fetalis. Antibody identification test revealed the presence of a pan-reactive antibody. Investigations realized in CNRGS (Paris) concluded in anti-GE2+anti-RH3+autoantibody. The red cell phenotype was GE: -2,3. A therapeutic interruption of the pregnancy was indicated. A program of autologous transfusion was organized with withdrawal of 2 units of blood. The 2nd pregnancy took place normally. Before delivery, an autologous blood reserve consisting of 2 red cell packs and 2 fresh frozen plasma was withdrawn and transfused after delivery. The management of anti-public alloimmunization poses several problems. The first one is of diagnostic nature with, on the one hand, the difficulty of Ab identification by the available red cell panels and, on the other hand, the possible presence of alloantibodies of transfusional or obstetric interest masked by anti-public Ab. The second is represented by transfusional care of these patients. In the absence of a national reserve of frozen rare blood, the autologous transfusion remains the only alternative. However, it can answer only a limited number of indications and only in case of moderate blood loss., (Copyright © 2016. Published by Elsevier SAS.)

In Tunisia, blood donation is voluntary, anonymous and non-remunerated. The aim of the study is to analyze donor motivation and sociology in the regional center of transfusion of Sfax. Between 14 May 2007 and 23 June 2007, a total of 903 Tunisian blood donors filled a questionnaire. Among the donors, 81.8% were men and have a mean age of 34.2 years and the majority of them have an age between 18 and 29 years. The middle social class was majority (77.8%) as well as the liberal profession (65.1%). Primary and secondary education were dominant (79.3%). Among the blood donors, 41.6% were new donors and 28.6% had a history of a single donation, 50.3% were voluntary and 49.7% replacement donors. The reasons motivating the voluntary donation were solidarity (69.9%), religion (21.2%), health benefit (3.6%) and insurance for the family (5.2%). The replacement donors refuse the voluntary donation for not obvious reasons (51%), lack of availability (13.3%), difficulties of accessibility of the sites of collection (7.6%), phobia of the blood and the stings (4.02%) or by refusal of blood donation (1.79%). The information and the raising awareness of the replacement donors could change in a near future their attitudes to become voluntary and regular donors. The implication of donor associations in the organization of the collections and the promotion of the blood donation would be of considerable contribution., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

As a continuation of previous research on a new series of potent and efficacious P-gp-dependent multidrug resistant (MDR) reversers with a N,N-bis(cyclohexanol)amine scaffold, we have designed and synthesized several analogs by modulation of the two aromatic moieties linked through ester functions to the N,N-bis(cyclohexanol)amine, aiming to optimize activity and to extend structure-activity relationships (SAR) within the series. This scaffold, when esterified with two different aromatic carboxylic acids, gives origin to four geometric isomers (cis/trans, trans/trans, cis/cis and trans/cis). The new compounds were tested on doxorubicin-resistant erythroleukemia K562 cells (K562/DOX) in the pirarubicin uptake assay. Most of them resulted in being potent modulators of the extrusion pump P-gp, showing potency values ([I](0.5)) in the submicromolar and nanomolar range. Of these, compounds 2b, 2c, 3d, 5a-d and 6d, showed excellent efficacy with a α(max) close to 1. Selected compounds (2d, 3a, 3b, 5a-d) were further studied to evaluate their doxorubicin cytotoxicity potentiation (RF) on doxorubicin-resistant erythroleukemia K562 cells and were found able to enhance significantly doxorubicin cytotoxicity on K562/DOX cells. The results of both pirarubicin uptake and the cytotoxicity assay, indicate that the new compounds of the series are potent P-gp-mediated MDR reversers. They present a structure with a mix of flexible and rigid moieties, a property that seems critical to allow the molecules to choose the most productive of the several binding modes possible in the transporter recognition site. In particular, compounds 5c and 5d, similar to the already reported analogous isomers 1c and 1d,(29) are potent and efficacious modulators of P-gp-dependent MDR and may be promising leads for the development of MDR-reversal drugs., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Purpose of the Study: To evaluate the prevalence of alloimmunization in women followed in an obstetrical environment in Tunisia, to identify the specificities of antibodies found and to determine factors that could influence the appearance of this immunization., Methods: We proceeded to a retrospective analysis of search for irregular antibodies in women followed up in obstetrical environment over nine consecutive years (2000-2008). The panel was officially defined and produced by the Regional Centre for Blood Transfusion in Sfax (Tunisia)., Results: Overall 5369 women benefited from 6575 antibody testing (average: 1.22; extremes: 1-14). The results were positive for 278 women (5.17 %), allowing to identify 216 antibodies or associations of antibodies. Among identified antibodies, those immune were found in 198 women. The rate of alloimmunization was 3.68 % (198/5369). The majority of the antibodies found was anti-Rh1, isolated or associated with another antibody, in 84.3 % of the total immunized women. The immunization of women according to the number of gestations showed a significant increasing rate ranging from 2.34 % for a first gestation to 5.27 % for four gestations or more. In addition, a significant difference was also noted between the rate of immunization in women who had received anti-Rh1 immunoglobulin and those who had not., Conclusion: Anti-Rh1 immunization is the most frequent in the population of studied women. This could denote of an insufficiency in pregnancies follow-up and immunoprophylaxis protocols., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

The aims of this study is to determine the hemogram reference values in a population of healthy adults of the region of Sfax, to compare our results with those from the literature, to estimate the age and sex variations in the blood count. The hemogram parameters were analyzed in 1000 blood donors. Hemogram was performed using Coulter ACT10's analyser. The differential leukocyte count was manually performed. The means of erythrocyte count, hemoglobin, haematocrit and red cell indices were significantly lower in women than in men. There was a significant variation in the red blood cell count, hemoglobin and haematocrit with age. There is also sex and age differences of the leukocyte count. The neutrophil and eiosinophil counts were higher in women than in men. The lymphocytes decreased with age in both sexes. The platelet count was significantly higher in women than in men. These results can be applied only to our local population of adults. The definition of reference values for the Tunisian population requires a study on a more diversified population, including more important number of individuals from various regions of the country.