Impact of psychological stress on the outcomes of assisted reproduction in Tunisian infertile women

Introduction: childlessness is an emotionally difficult experience for infertile couples. Undergoing assisted reproductive treatments (ART) could generate further stress in these patients. Studies investigating the impact of anxiety on ART outcomes have shown controversial results. Moreover, there are no publications focusing on anxiety symptomsin infertile Tunisian couples. Methods: we conducted a prospective study including 79 infertile women undergoing in vitro fertilization at the Reproductive Medicine Unit of the Farhat Hached Hospital (Tunisia). Participants were asked to answer to the Beck anxiety inventory (BAI) on the day of oocyte retrieval. Accordingly, they were classified into the 3 groups: group A: very low anxiety (n= 36; BAI<21), group B: moderate anxiety (n= 24; 22≤BAI≤35) and group C: severe anxiety (n=19; BAI≥36). For each patient, two blood samples were collected to assess free cortisol level on the day of oocyte retrieval and on the day of embryo transfer. Results: results showed that women with primary infertility were significantly more stressed than those with secondary infertility (p= 0.011). Cortisol level was significantly higher on the day of embryo transfer than on the day of oocyte pick-up (p<0.0001). A lower implantation rate was found in severely anxious patients compared with moderately anxious women (p= 0.03) and those having low levels of anxiety (p= 0.001) and was negatively correlated to BAI score (r= -0.65; p= 0.001). Both clinical pregnancy and livebirth rates were similar among the three groups. Conclusion: the day of embryo transfer is the most stressful timepoint and psychological counseling is crucial to enhance implantation rate. Hence implantation took place, no effect of stress on pregnancy and live birth was found

Nonlinear Control Strategies of an Autonomous Double Fed Induction Generator Based Wind Energy Conversion Systems

In the last few decades, among the wide range of renewable energy sources, wind energy is widely used. Variable speed wind energy conversion systems based on double fed induction generator have a considerable interest mostly in case of islanded networks and/or isolated applications. In this paper, as a means to supply remote areas, an investigation of a wind energy conversion system (WECS) based on a double fed induction generator (DFIG) is carried out. The presence of both wind turbine aerodynamics and DFIG coupled dynamics causes strong nonlinearities in the studied system. Wind speed and demanded power variations have a major impact on the quality of the produced energy. In order to control and maintain the stator output voltage and frequency at their nominal values (220 V/50 Hz) under wind speed and load variations, this work presents a study of three kinds of controllers: PI, Back-Stepping and Sliding Mode controllers. These controllers are integrated in the studied system and a comparison of their dynamic performances has been developed. Moreover, in order to ensure the rotor side converter safety on the one hand and to guarantee an optimal operation of the DFIG on the other hand, a management strategy is proposed in this work. Simulation results are performed using Matlab/Simulink environment and show the effectiveness and the accuracy of each controller compared to others mainly with the presence of wind speed and load demand variations

On-line Electrochemical Impedance Spectroscopy method for PV diagnosis system

PV fault conditions in photovoltaic (PV) systems reduce panel power performance and accelerate cell degradation. In this way, many research have recently turned to the diagnosis of PV generator to minimize the cost of the produced energy and ensure reliable power production. This paper proposes a new PV diagnosis system based on on-line Electrochemical Impedance Spectroscopy. This latter is used to estimate internal parameters of PV panel connected to a resistive load via a DC/DC boost converter. The Nyquist Diagram allows to plot and evaluate dynamic impedance response versus variable low frequency signal injected in conjunction with the high frequency system allowing to operate the PV in MPPT condition. The dynamic single diode model with a series resistance, a shunt resistance and a junction capacitance is used to design the PV model in MATLAB/Simulink. Simulations results are given for normal and for faulty operation whether in the PV panel or in the load. Referring to these results, it is concluded that the proposed diagnosis method allows to detect PV panel faults regardless of load variation

Antibiotic resistance in Escherichia coli in husbandry animals. The African perspective

In the last years different surveillances have been published in Africa, especially in Northern countries, regarding antimicrobial resistance among husbandry animals. Information is still scarce, but the available data shows a worrying picture. Although the highest resistance rates have been described against tetracycline, penicillins and sulphonamides, prevalence of plasmid mediated quinolone resistance genes and extended-spectrum -lactamase (ESBL) are being increasingly reported. Among ESBLs, the CTX-M-1 group was dominant in most African surveys, being CTX-M-15 the main variant both in animals and humans, except in Tunisia where CTX-M-1 was more frequently detected among E. coli from poultry. Certain blaCTX-M-15-harboring clones (ST131/B2 or ST405/D) are mainly identified in humans but they have also been reported in livestock species from Tanzania, Nigeria or Tunisia. Moreover, several reports suggest an inter-host circulation of specific plasmids (e.g. blaCTX-M-1-carrying IncI1/ST3 in Tunisia, IncY and Inc-untypeable replicons co-harboring qnrS1 and blaCTX-M-15 in Tanzania and the worldwide distributed blaCTX-M-15-carrying IncF-type plasmids). International trade of poultry meat seems to have contributed to the spread of other ESBL variants, such as CTX-M-14, and clones. Worryingly, first descriptions of OXA-48 and OXA-181-producing E. coli have been recently documented in cattle from Egypt, and the emergent plasmid-mediated colistin resistance mcr-1 gene has been also identified in chickens from Algeria, Tunisia and South Africa. These data reflect the urgent need of a larger regulation in the use of veterinary drugs and the implementation of surveillance programmes in order to decelerate the advance of antimicrobial resistance in this continent

Detection of CTX-M-15 harboring Escherichia coli isolated from wild birds in Tunisia

Abstract Background The spreading of antibiotic resistant bacteria is becoming nowadays an alarming threat to human and animal health. There is increasing evidence showing that wild birds could significantly contribute to the transmission and spreading of drug-resistant bacteria. However, data for antimicrobial resistance in wild birds remain scarce, especially throughout Africa. The aims of this investigation were to analyze the prevalence of ESBL-producing E. coli in faecal samples of wild birds in Tunisia and to characterize the recovered isolates. Results One hundred and eleven samples were inoculated on MacConkey agar plates supplemented with cefotaxime (2 μg/ml). ESBL-producing E. coli isolates were detected in 12 of 111 faecal samples (10.81%) and one isolate per sample was further characterized. β-lactamase detected genes were as follows: bla CTX-M-15 (8 isolates), bla CTX-M-15 + bla TEM-1b (4 isolates). The ISEcp1 and orf477 sequences were found respectively in the regions upstream and downstream of all bla CTX-M-15 genes. Seven different plasmid profiles were observed among the isolates. IncF (FII, FIA, FIB) and IncW replicons were identified in 11 CTX-M-15 producing isolates, and mostly, other replicons were also identified: IncHI2, IncA/C, IncP, IncI1 and IncX. All ESBL-producing E. coli isolates were integron positive and possessed “empty” integron structures with no inserted region of DNA. The following detected virulence genes were: (number of isolates in parentheses): fimA (ten); papC (seven); aer (five); eae (one); and papGIII, hly, cnf, and bfp (none). Molecular typing using pulsed-field gel electrophoresis and multilocus sequence typing showed a low genetic heterogeneity among the 12 ESBL-producing strains with five unrelated PFGE types and five different sequence types (STs) respectively. CTX-M-15-producing isolates were ascribed to phylogroup A (eleven isolates) and B2 (one isolate). Conclusion To our knowledge, this study provides the first insight into the contribution of wild birds to the dynamics of ESBL-producing E. coli in Tunisia

Occurrence of Textile Dyes and Metals in Tunisian Textile Dyeing Effluent: Effects on Oxidative Stress Status and Histological Changes in Balb/c Mice

Although it is known that textile wastewater contains highly toxic contaminants whose effects in humans represent public health problems in several countries, studies involving mammal species are scarce. This study was aimed to evaluate the toxicity profile of 90-days oral administration of textile dyeing effluent (TDE) on oxidative stress status and histological changes of male mice. The TDE was collected from the textile plant of Monastir, Tunisia and evaluated for the metals, aromatic amines, and textile dyes using analytical approaches. Metal analysis by ICP-MS showed that the tested TDE exhibited very high levels of Cr, As, and Sr, which exceeded the wastewater emission limits prescribed by WHO and Tunisian authority. The screening of TDE through UPLC-MS/MS confirmed the presence of two textile dyes: a triphenylmethane dye (Crystal violet) and a disperse azo dye (Disperse yellow 3). Exposure to TDE significantly altered the malondialdehyde (MDA), Conjugated dienes (CDs), Sulfhydryl proteins (SHP) and catalase levels in the hepatic and renal tissues. Furthermore, histopathology observation showed that hepatocellular and renal lesions were induced by TDE exposure. The present study concluded that TDE may involve induction of oxidative stress which ensues in pathological lesions in several vital organs suggesting its high toxicity. Metals and textile dyes may be associated with the observed toxicological effects of the TDE. These pollutants, which may have seeped into surrounding rivers in Monastir city, can cause severe health malaise in wildlife and humans.Ministry of Higher Education and Scientific Research in Tunisi