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This paper deals with the adaptive blind source separation problem in presence of impulsive noise. New algorithms extending the well known SOBI method from batch to adaptive scheme are introduced. At first, the standard Gaussian noise case is considered, leading to our first algorithm referred to as Adaptive SOBI (A-SOBI). Later on, a robust version of A-SOBI, referred to as RA-SOBI is derived to handle the impulsive noise case. RA-SOBI relies on robust subspace tracking for the whitening stage together with robust correlation estimation for the separation stage. All proposed algorithms are of relatively low complexity and allow to achieve good separation quality as illustrated by our simulation results.

This study was conducted to investigate first the bacterial contamination by Enterobacteriaceae, fecal coliforms and the prevalence of Salmonella spp. and second to identify the main associated risk factors in Algerian farms, slaughterhouses and butcheries during a two-years period. Thus, a cross-sectional study was performed using a simple random sampling method to target 20 farms, 10 slaughterhouses and 5 butcheries. A structured questionnaire was further used to assess hygienic status of the farms and slaughterhouses. A total of 265 samples were collected from wall, floor, litter, food, water and animals' samples composed mainly of meat, neck skin and liver. Samples from walls and floors, from different sites were analyzed to evaluate the overall contamination and the hygiene of sites for Total viable bacteria, Enterobacteriaceae counts and Fecal coliforms counts. Furthermore, E.coli and salmonella spp. were identified in all samples. The overall contamination by sampling sites expressed as log10 CFU/g (mean ± SD) for Total Aerobic Microbial Count, Enterobacteriaceae count and fecal coliforms counts were around 4.71 ± 1.1, 4.73 ± 1.3 and 4.68 ± 1.2 respectively. The findings evidenced that the prevalence of E.coli and Salmonella spp. were 63.40% and 18.49% respectively. The highest rate of E.coli contamination was for poultry farms (70%), beef farms (64%) and butcheries (74.54%) followed by poultry meat slaughterhouses (60%) and sheep farms (48%) while beef slaughterhouses have the lowest rate of contamination (33.84%). For salmonella spp. the contamination was found to be mainly in poultry meat slaughterhouses (31.11%), butcheries (25.45%), followed by poultry farms (22%), beef farms (20%) and sheep farms (12%) while beef slaughterhouses have the lowest rate of contamination (4.61%). This study evidenced multifactor effects of microbial contamination in farms such as animal density, litter hygiene and scraping, manure storage, water and pest control, contact with other animals and decontamination process. Overall, this trial indicated a high rate of microbial contamination for which further studies are needed to determine all the potential risk factors in order to evaluate the corrective effects.

Background: Congenital bilateral absence of vas deferens (CBAVD) is responsible for 2-6% of male infertility. It occurs in 95% of men with cystic fibrosis. This malformation is present in patients with a sterile obstructive azoospermia but without clinical evidence of cystic fibrosis. Molecular study of the cystic fibrosis transmembrane conductance regulator ( CFTR) gene responsible for cystic fibrosis could show the relationship between this disease and bilateral absence of vas deferens. Patients and methods: The study involved 20 male patients aged between 28-40 years, referred with suspected cystic fibrosis and in whom bilateral absence of vas deferens was confirmed by cyto-biochemical analyses and urogenital ultrasound. Molecular study of the CFTR gene was based on several techniques: DHPLC, DGGE and direct sequencing. Results: Thirteen patients had CFTR mutations: F508del, G542X, W1282X, E1104X, 711++1G → T, V201M (TG) m and IVS8-5T. These mutations were associated with polymorphisms: M470V and D1270N. Seven cases presented only polymorphisms. Conclusion: The different mutations found in this study were associated with polymorphisms which decrease the severity of the disease and delay its onset. Thus, bilateral agenesis of the vas deferens is classed as a form of cystic fibrosis with only genital expression. [ABSTRACT FROM AUTHOR]

Microcavity lasers are of interest for both fundamental studies of cavity quantum electrodynamics and for potential applications in all-optical networks. Among the different types of microcavities, the microdisk is especially suited for fabricating polymer microcavity lasers. Current research with microdisk lasers has focused on two areas: (1) directional laser emission; and (2) laser threshold minimization. The laser emissions are obtained with optical pumping performed by focusing the pump laser directly on the top face of the microdisks. We present the lasing characteristics of optically pumped luminescent polymer microdisks on semiconductor substrates. Geometrical parameters such as radius disks are shown to affect the lasing threshold. [Copyright &y& Elsevier]

Abnormalities of coagulation and fibrinolysis were studied in a group of 28 children and young adults with homozygous sickle cell disease (SCD), either in the steady state (n = 12) or during painful crisis (n = 16). Coagulation was explored by standard clotting tests and by measurement of prothrombin complex factors, factor VIII (VIII:C) and antithrombin III (ATIII), protein C (PC) and protein S (PS) activities, while fibrinolytic potential was evaluated using D-dimer, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) assays. In SCD patients, thrombin time (TT) was constantly shortened, both in the steady state (ratio to control 0.83 ± 0.08, p < 0.0001) and in crisis (0.76 ± 0.06, p < 0.0001). Mean levels of prothrombin complex were similar in asymptomatic patients to those in controls, but were significantly decreased during sickle cell crisis (p < 0.05 for factor V and p < 0.0001 for factors II,VII and X). Factor VIII:C was significantly increased, both in the steady state (207 ± 35%, p < 0.0001) and during crisis (208 ± 34 %, p < 0,0001). PS activity was reduced in the steady state (81 ± 12%, p < 0.01) and further diminished in crisis (68.5 ± 27.5%, p < 0.001), while D-dimers were significantly elevated during sickle cell crisis (1028 ± 675 ng/ml, p < 0.001). In all SCD patients, baseline levels of t-PA antigen were comparable to those in controls, whereas concentrations of PAI-1 antigen were significantly increased, either in the steady state (89.7 ± 26.3 ng/ml, p < 0.0001) or in crisis (75.0 ± 24.8 ng/ml, p < 0.0001). These results provide evidence for the presence of circulating activated clotting factors in SCD and for an imbalance of the profibrinolytic and antifibrinolytic systems most likely due to increased PAI-1 levels. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Sickle cell disease (SCD) is a group of hereditary chronic anemias that manifest essentially as painful crisis and susceptibility to infection. Neonatal screening is a preventive action that reduces the rates of mortality due to complications arising from infections by encouraging early prophylactic penicillin use and pneumococcal vaccination. The purpose of this pilot study was to set up a neonatal screening protocol at a lower cost than one that uses commercially available screening kits. DESIGN AND SETTING: Pilot study conducted over 1 year in two Tunis maternity hospitals. PATIENTS AND METHODS: Samples from 9148 newborns were collected using paper printed using a common office printer to collect blood spots from the newborns. A lab-prepared agarose gel for isoelectrofocusing (IEF) was used to test the dried blood samples from these newborns. RESULTS: The IEF on lab-prepared agarose gels was efficient since it was able to detect the main abnormal Hbs previously identified in the Tunisian population (HbS, HbC, HbO, and HbG). Furthermore, when data collected in this screening program were compared with the previously established national data, no statistically significant differences were found. After analysis, results were given back to the families of the patients, and the major Hb cases were directed to one of the hemoglobinopathies specialized centers, where at-risk couples benefited from genetic counselling and were informed about the possibility of prenatal diagnosis. CONCLUSION: This pilot experiment demonstrated the feasibility of SCD neonatal detection using a lower cost method as well as detection of other main structural Hb variants.

Introduction: Growth Hormone Deficiency (GHD) is a rare disease marked by a complete or partial reduction in the production of growth hormone. Vitamin D deficiency is frequent and may be associated with several pathologies. However, the association between GHD and vitamin D deficiency has not been extensively studied. This study aimed to analyse VDR gene polymorphisms related to vitamin D status to ensure better care for patients with GHD., Material and Methods: A case-control study was conducted at the Children's Hospital of Tunis in collaboration with the Farhat Hached's Hospital of Sousse, including patients with GHD and healthy subjects. Genetic analysis of the VDR gene polymorphisms was performed using PCR-RFLP technique. Haplotypes were examined with Haploview software, while statistical analyses were carried out using SPSS and R programming language., Results: Our study revealed significant differences in vitamin D (p = 0, 049) and calcium concentrations between patients and healthy subjects, which were lower in the GHD group (p = 0,018). A comparison of allelic and genotypic frequencies of the five polymorphisms indicated an association between the Fok I polymorphism and GHD. Furthermore, significant difference was observed between the Apa I genotypes and PTH (p = 0,019) and ALP (p = 0,035). Fok I genotypes were associated with phosphorus (p = 0,021). Additionally, One haplotype, CTAGT, exhibited a significant difference between the patients and healthy subjects (p = 0,002)., Conclusion: Our study findings indicate that hypovitaminosis D is common among patients with GHD, even when undergoing treatment with rhGH. This underscores the critical importance of vitamin D supplementation during treatment., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Familial Hypophosphatasia presents a complex diagnostic challenge due to its wide-ranging clinical manifestations and genetic heterogeneity. This study aims to elucidate the molecular underpinnings of familial Hypophosphatasia within a Tunisian family harboring a rare c.896 T > C mutation in the ALPL gene, offering insights into genotype-phenotype correlations and potential therapeutic avenues. The study employs a comprehensive approach, integrating biochemical examination, genetic analysis, structural modeling, and functional insights to unravel the impact of this rare mutation. Genetic investigation revealed the presence of the p.Leu299Pro mutation within the ALPL gene in affected family members. This mutation is strategically positioned in proximity to both the catalytic site and the metal-binding domain, suggesting potential functional consequences. Homology modeling techniques were employed to predict the 3D structure of TNSALP, providing insights into the structural context of the mutation. Our findings suggest that the mutation may induce conformational changes in the vicinity of the catalytic site and metal-binding domain, potentially affecting substrate recognition and catalytic efficiency. Molecular dynamics simulations were instrumental in elucidating the dynamic behavior of the tissue-nonspecific alkaline phosphatase isozyme (TNSALP) in the presence of the p.Leu299Pro mutation. The simulations indicated alterations in structural flexibility near the mutation site, with potential ramifications for the enzyme's overall stability and function. These dynamic changes may influence the catalytic efficiency of TNSALP, shedding light on the molecular underpinnings of the observed clinical manifestations within the Tunisian family. The clinical presentation of affected individuals highlighted significant phenotypic heterogeneity, underscoring the complex genotype-phenotype correlations in familial Hypophosphatasia. Variability in age of onset, severity of symptoms, and radiographic features was observed, emphasizing the need for a nuanced understanding of the clinical spectrum associated with the p.Leu299Pro mutation. This study advances our understanding of familial Hypophosphatasia by delineating the molecular consequences of the p.Leu299Pro mutation in the ALPL gene. By integrating genetic, structural, and clinical analyses, we provide insights into disease pathogenesis and lay the groundwork for personalized therapeutic strategies tailored to specific genetic profiles. Our findings underscore the importance of comprehensive genetic and clinical evaluation in guiding precision medicine approaches for familial Hypophosphatasia., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)