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This research investigates the influence of synthesis kinetics on the structural and photocatalytic properties of chitosan–clay nanocomposites (Cs/MMT) and chitosan–hectorite nanocomposites (Cs/HET), employing an optimized initial stoichiometry of 1:3. Utilizing a variety of analytical techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR), the study explores the structural evolution of the nanocomposites and their photocatalytic performance using semiconductor catalysts TiO2 and ZnO. The findings emphasize the significant impact of reaction kinetics, particularly after 3 h of reaction time, on the structural features of the nanocomposites. Notably, Cs/MMT demonstrates greater crystalline stability compared to Cs/HET due to variations in octahedral cavity occupancy in the initial clays. FTIR and TEM analyses depict the progressive evolution of the nanocomposites during the reaction, shedding light on how reaction kinetics drive the formation of specific bonds within the nanocomposites. In terms of photocatalytic activity, this study provides insights into the complex dynamics of photocatalytic degradation, with a specific focus on the performance of TiO2 and ZnO under diverse experimental conditions. The superior efficacy of TiO2 as a catalyst, particularly when integrated with Cs/MMT nanocomposites, is unequivocally demonstrated, with degradation rates exceeding 80%. This preference stems from TiO2 consistently exhibiting higher degradation rates compared to ZnO, attributed to structural disparities between montmorillonite and hectorite, influencing catalyst–support interactions. The findings underscore the critical importance of selecting suitable catalyst and support matrix combinations for optimizing performance in specific applications.

To improve the intrinsic qualities of hybrid nanocomposite (NC), polymer, clay, and metallic oxide are combined. This study investigates the effects of starting stoichiometry variation on the microstructural and functional properties of synthesized hybrid NC composed of chitosan (CTS), Na-montmorillonite (MMT), and ZnO nanoparticles (NPs). To carry out the synthesized process, a solution blending approach is used. A correlation of the outcomes from the several analyses methods such as X-ray diffraction (XRD), Fourier Transform InfraRed spectroscopy (FTIR), Transmission Electron Microscopy (TEM), Impedance spectroscopy (IS), and UV–VIS spectrophotometry ensures the accuracy of the analysis. Regardless of the initial stoichiometry rate, the microstructural analysis shows that NC can be successfully synthesized. The growth and changes in the intensity and sharpness of the characteristic reflections shown by the semiquantitative XRD analysis suggest that the synthesis process was certainly successful. The apparent structure aberration, caused by the stoichiometry fluctuation, is manifested as an XRD reflection position shift and varied intensity strength.The intercalation process and the exfoliation of ''clay-particles'' enclosing the organic fraction, according to TEM/EDX experiments, occurred as the clayey fraction's abundance surged. Despite the variable ratio approved at the start of the synthesis process, FTIR spectroscopy displays the polymer fraction's characteristic absorption bands. Synthesized NC has significant UV blocking properties while retaining good transparency in the visible range. This behavior may have its roots throughout the fact that the CS surface modification has induced the bandgap energy fluctuation of ZnO NPs. The photocatalytic activity of the produced NC is evaluated using MB degradation measurements. The outcomes are extremely positive for the sample with a starting stoichiometry almost equally distributed between CTS and ZnO (NPs). Results from the IS, for the selected sample, shows that synthesized NC exhibits semiconductor behavior,and as a dielectric material, the sample is dispersive with a power loss over a specific frequency range.

Study aim: The aim of the study was to analyse the lifespan of Polish male Olympic medallists in comparison to the general male population.

Abstract Lateral luxation is defined as a traumatic displacement of a tooth in any direction other than axially. A laterally luxated tooth is often immobile because of its bony lock. It produces a high metallic sound during percussion. Pulp sensibility testing is likely to be negative during the initial follow‐up. However, the tooth should be monitored until a definitive pulp diagnosis is made. Treatment includes local anesthesia, suturing soft tissue injuries, manual repositioning of the luxated tooth, and stabilization with a flexible splint for 4 weeks. Given the risk of pulp necrosis following lateral luxation, particularly in teeth with radiographically closed apices and severe displacement, an immediate (prophylactic) root canal treatment is recommended. The objective of this work was to report and discuss the management of a case of lateral luxation involving a permanent tooth treated by reduction, followed by contention with 0.4 steel wire and composite resin, and endodontic treatment, and which was complicated by root resorption 3 months later. We also highlighted the possible complications following lateral luxation, especially root resorption.

Objectives. This work aimed to estimate the knowledge and practice of general dentists in the governorate of Manouba regarding the management of patients at risk of infective endocarditis. Materials and Methods. A survey involving private sector general dentists in the governorate of Manouba was performed. It contained 21 questions, and it was addressed to 111 dentists. Only 82 dentists responded. To carry out the descriptive study, we used the SPSS software version 21.0. Results. Our results proved the lack of knowledge among dentists in the governorate of Manouba with regard to the management of patients at risk of infective endocarditis. An overestimation of the risk and an overprescription of antibiotic were found in order to ensure an over-protection for the patients as well as the dentist. In fact, 85.4% of these dentists prescribed antibiotic prophylaxis for the two groups of patients (high risk and moderate risk). Only 9.8% followed the right modality of antibiotic prophylaxis prescription; 4.9% of the dentists prescribed antibiotic only 1 hour before the act and 4.9% of them prescribed antibiotic 1 hour before the act and continued the treatment in case of the presence of an infectious site. Conclusion. A discrepancy towards an over-estimation of risk and overprescription of antibiotic was found between the recommendations and real practice. Similar studies in the other governorates of Tunisia are recommended in order to better understand the problem.

Abstract Background Hypopituitarism is a recognized sequela of traumatic brain injury (TBI) and may worsen the quality of life (QoL) in survivors. Aims To assess the prevalence of post‐traumatic hypopituitarism (PTHP) and growth hormone deficiency (GHD), and determine their correlation with QoL. Methods Survivors of moderate to severe TBI were recruited from two Algerian centres. At 3 and 12 months, pituitary function was evaluated using insulin tolerance test (ITT), QoL by growth hormone deficiency in adults’ questionnaire (QoL‐AGHDA), and 36‐item short‐form (SF‐36) health survey. Results Of 133 (M: 128; F: 5) patients aged 18‐65 years, PTHP and GHD were present at 3 and 12 months in 59 (44.4%) and 23 (17.29%), 41/116 (35.3%) and 18 (15.5%). Thirteen patients with GHD at 3 months tested normally at 12 months, while 9 had become GHD at 12 months. At 3 and 12 months, peak cortisol was

Usher syndrome (USH) is an autosomal recessive disorder characterized by a dual sensory impairment affecting hearing and vision. USH is clinically and genetically heterogeneous. Ten different causal genes have been reported. We studied the molecular bases of the disease in 18 unrelated Algerian patients by targeted-exome sequencing, and identified the causal biallelic mutations in all of them: 16 patients carried the mutations at the homozygous state and 2 at the compound heterozygous state. Nine of the 17 different mutations detected in MYO7A (1 of 5 mutations), CDH23 (4 of 7 mutations), PCDH15 (1 mutation), USH1C (1 mutation), USH1G (1 mutation), and USH2A (1 of 2 mutations), had not been previously reported. The deleterious consequences of a missense mutation of CDH23 (p.Asp1501Asn) and the in-frame single codon deletion in USH1G (p.Ala397del) on the corresponding proteins were predicted from the solved 3D-structures of extracellular cadherin (EC) domains of cadherin-23 and the sterile alpha motif (SAM) domain of USH1G/sans, respectively. In addition, we were able to show that the USH1G mutation is likely to affect the binding interface between the SAM domain and USH1C/harmonin. This should spur the use of 3D-structures, not only of isolated protein domains, but also of protein-protein interaction interfaces, to predict the functional impact of mutations detected in the USH genes.

Usher syndrome (USH) is an autosomal recessive disorder characterized by combined deafness-blindness. It accounts for about 50% of all hereditary deafness blindness cases. Three clinical subtypes (USH1, USH2, and USH3) are described, of which USH1 is the most severe form, characterized by congenital profound deafness, constant vestibular dysfunction, and a prepubertal onset of retinitis pigmentosa. We performed whole exome sequencing in four unrelated Tunisian patients affected by apparently isolated, congenital profound deafness, with reportedly normal ocular fundus examination. Four biallelic mutations were identified in two USH1 genes: a splice acceptor site mutation, c.2283-1G>T, and a novel missense mutation, c.5434G>A (p.Glu1812Lys), in MYO7A, and two previously unreported mutations in USH1G, i.e. a frameshift mutation, c.1195_1196delAG (p.Leu399Alafs*24), and a nonsense mutation, c.52A>T (p.Lys18*). Another ophthalmological examination including optical coherence tomography actually showed the presence of retinitis pigmentosa in all the patients. Our findings provide evidence that USH is under-diagnosed in Tunisian deaf patients. Yet, early diagnosis of USH is of utmost importance because these patients should undergo cochlear implant surgery in early childhood, in anticipation of the visual loss.

Identification of the causative mutations in patients affected by autosomal recessive non syndromic deafness (DFNB forms), is demanding due to genetic heterogeneity. After the exclusion of GJB2 mutations and other mutations previously reported in Tunisian deaf patients, we performed whole exome sequencing in patients affected with severe to profound deafness, from four unrelated consanguineous Tunisian families. Four biallelic non previously reported mutations were identified in three different genes: a nonsense mutation, c.208C>T (p.R70X), in LRTOMT, a missense mutation, c.5417T>C (p.L1806P), in MYO15A and two splice site mutations, c.7395+3G>A, and c.2260+2T>A, in MYO15A and TMC1 respectively. We thereby provide evidence that whole exome sequencing is a powerful, cost-effective screening tool to identify mutations causing recessive deafness in consanguineous families.

Abstract Background Alzheimer's disease (AD) is a complex disorder that involves multiple biological processes. Many genes implicated in these processes may be present in low abundance in the human brain. DNA microarray analysis identifies changed genes that are expressed at high or moderate levels. Complementary to this approach, we described here a novel technology designed specifically to isolate rare and novel genes previously undetectable by other methods. We have used this method to identify differentially expressed genes in brains affected by AD. Our method, termed Subtractive Transcription-based Amplification of mRNA (STAR), is a combination of subtractive RNA/DNA hybridization and RNA amplification, which allows the removal of non-differentially expressed transcripts and the linear amplification of the differentially expressed genes. Results Using the STAR technology we have identified over 800 differentially expressed sequences in AD brains, both up- and down- regulated, compared to age-matched controls. Over 55% of the sequences represent genes of unknown function and roughly half of them were novel and rare discoveries in the human brain. The expression changes of nearly 80 unique genes were further confirmed by qRT-PCR and the association of additional genes with AD and/or neurodegeneration was established using an in-house literature mining tool (LitMiner). Conclusion The STAR process significantly amplifies unique and rare sequences relative to abundant housekeeping genes and, as a consequence, identifies genes not previously linked to AD. This method also offers new opportunities to study the subtle changes in gene expression that potentially contribute to the development and/or progression of AD.

Aim: To assess the relationship between cardiothoracic ratio (CTR) and ventricular and atrial volumes in patients with repaired tetralogy of Fallot (TOF)., Materials and Methods: Patients with repaired TOF undergoing cardiac magnetic resonance (CMR) and chest radiography within 1 day were included (n = 82; median age: 24.7 years, interquartile range: 21.5-35.9). The CTR was obtained from upright posteroanterior chest roentgenograms. Analyses of CMR images and radiographs were performed in a blinded fashion., Results: There were 35.1% (13/37) of patients with normal CTR (<0.5) who had severe right ventricular (RV) dilatation. There were six patients (13.3%, 6/45) with high CTR with both normal RV and left-ventricular (LV) volumes. CTR did not correlate with either RV or LV volumes but showed a weak correlation with right- and left-atrial volumes (r = 0.43, p = 0.0001; r = 0.27, p = 0.01, respectively). CTR ≥0.5 showed poor ability in the identification of severe RV dilatation (sensitivity: 61.8%, specificity: 50%). The combination of CTR and signs of RV enlargement on lateral radiographs did not improve the diagnostic accuracy of any of those parameters alone., Conclusion: CTR in patients with repaired TOF reflected atrial rather than ventricular dilatation. The use of CTR or lateral radiographs in patients with repaired TOF may lead to false conclusions concerning ventricular size., (Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Background: Hypertrophic obstructive cardiomyopathy (HOCM) is characterised by asymmetric myocardial hypertrophy, which is most pronounced in the interventricular septum (IVS) and is responsible for the dynamic obstruction of the left ventricular outflow tract (LVOT). Successful alcohol septal ablation (ASA) of the IVS allows to reduce the thickness of the parabasal part of the IVS myocardium and, in most cases, to permanently reduce the gradient in the LVOT., Aim: To assess, using cardiac magnetic resonance imaging (MRI) and transthoracic echocardiography (TTE), the impact of gradient reduction in the LVOT on the type and severity of left ventricular (LV) remodelling., Methods: The study included 30 patients (aged 56.9 ± 11.9 years) with HOCM and the mean peak gradient (PG) in the LVOT of 123 ± 33 mm Hg who underwent ASA. MRI measurements were performed before and at 6 months after ASA and TTE measurements were performed before, at 3 months and at 6 months after ASA., Results: PG in the LVOT decreased to an average of 52 ± 37 mm Hg (p 〈 0.0001) at 3 months after ASA and to 37 ± 28 mm Hg (p 〈 0.0001) at 6 months after ASA. TTE revealed a decrease in IVS thickness outside the scar following ASA from 23.6 ± 3.5 mm to 19.3 ± 4.0 mm (p 〈 0.0001) and 19.4 ± 0.4 mm (p 〈 0.0001) at 3 and 6 months, respectively. There was also a decrease in lateral wall (PW) thickness from 15.9 ± 3.2 mm to 14.9 ± 2.9 mm (p = 0.046) and 14.16 ± 2.00 (p = 0.0065) at 3 and 6 months, respectively. MRI revealed a decrease in IVS thickness from 23.7 ± 2.8 mm to 18.04 ± 4.00 mm (p = 0.0001) at 6 months following ASA. We observed a regression of the PW hypertrophy from 13.2 ± 3.35 mm to 12.18 ± 2.4 mm (p = 0.0225). There was a decrease in IVS mass from 108.9 ± 20 g to 91.5 ± 29 g (p = 0.0006). There was a trend towards a decreased LV mass and LV mass excluding IVS mass at 6 months., Conclusions: A significant decrease in PG in the LVOT is associated with a decrease in LV mass and with regression of LV hypertrophy outside the scar after ASA.

Background: The diagnosis of left ventricular hypertrophy (LVH) in the presence of the left bundle branch block (LBBB) is difficult. In our study we compared commonly used ECG criteria with left ventricular mass index (LVMI) calculated during cardiac magnetic resonance imaging (CMRI) to verify their clinical value or the need to recalibrate., Methods: CMRI and ECG data of 36 patients were included in this study. Based on the ECG measures we used in our study selected ECG criteria for LVH detection in cases with LBBB: QRS duration, amplitude of S waves in V1, V2, V3; R waves in aVL, V5, V6 and combinations of amplitudes. LVH was defined as LVMI (CMRI) exceeding reference values., Results: LVH was diagnosed in 17 (47%) patients (6 women and 11 men). Following ECG parameters correlated the most prominently with LVMI - RV5: r = 0.5 (p = 0.002), RV6: r = 0.61 (p = 0.0001), SV1+RV5, 6: r = 0.64 (p = 0.001), RaVL+SV3: r = 0.5 (p = 0.002), SV2+RV5, 6: r = 0.71 (p = 0.0001), SV2, 3+RV5, 6: r = 0.75 (p = 0.0001). Based on the results of ROC analysis we proposed new cut points for LVH parameters. The highest diagnostic accuracy achieved S2+SV3 〉 6 mV, SV2,V3+RV5,V6 〉 4 mV, RaVL+SV3 〉 3.5 mV (86-89%)., Conclusions: In patients with LBBB the ECG parameters based on the amplitude of S wave in V2 or V3 and R wave in the leads aVL, V5, V6 have the highest clinical value in the prediction of the LVH determined by CMRI. It was necessary to recalibrate these parameters and it is needed to verify them in larger number of LBBB patients.