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Context and Results: In this study, the heterojunction Cu 2 O/TiO 2 is used for the degradation of a cationic dye, Rhodamine B, under solar light irradiation over a wide pH range. The physical and optical properties of both semiconductors Cu 2 O and TiO 2 are correlated with the photo-electrochemical characterization to establish the energy diagram of the heterojunction Cu 2 O/TiO 2 . X-ray diffraction, UV-visible, SEM, EDX, and BET analyses are conducted for both photocatalysts. The band gap (E g ) of 3.26 eV is obtained for TiO 2 with an indirect optical transition. In the case of Cu 2 O, the transition is directly allowed at 2.05 eV. According to the BET analysis, the specific surface area of TiO 2 particles is higher (82.65 m 2  g -1 ) than that of Cu 2 O (29.81 m 2  g -1 ). The flat band potentials, determined from the Mott-Schottky plots, are 0.3 and - 0.32 V SCE for TiO 2 and Cu 2 O, respectively. The photocatalytic activity is directly proportional to the mass ratio, and the best result is obtained for the mass ratio 1:1 of Cu 2 O/TiO 2 ., Computational and Theoretical Techniques: Furthermore, a theoretical study is conducted by using density functional theory to optimize the structure, reactivity sites of the RhB molecule, and physical parameters like the energy of the frontier molecular orbitals and electronegativity and to predict the proposed mechanism of RhB degradation as well as its intermediates. Also, molecular dynamics simulation is used to determine the adsorption behavior of RhB on TiO 2 (101) and Cu 2 O (111) surfaces. The ecotoxicity evaluation showed that degradation products have significantly lower acute toxicity than RhB., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this study, the photodegradation of organophosphorus (OPs) pesticides in the honey medium was evaluated under sunlight irradiation. Some of the 22 samples collected at different sites contained OPs pesticides (Methyl parathion, Coumaphos and Fenitrothion) with an average of 8 ng/g. Moreover, three samples were found with pesticide residue levels exceeding the maximum residue limits (MRL ≥ 50 ng/g) imposed by the standard water (WHO). Gas chromatography (GC) combined with a tritium electron capture detector system was used for the analysis of OPs pesticides in honey. Total degradation of the Methyl parathion was obtained in less than 60 min of irradiation. Moreover, the elimination of the other OPs found in the samples was also effective with a rate of 85% for Coumaphos and Fenitrothion after 50 min of sunlight irradiation. The kinetics of the photodegradation reaction of all OPs pesticides studied followed a pseudo-first order model.

Metal oxide p-n heterojunctions consisting of p-Cu 2 O/n-ZnO/n-ZnS nanostructures were deposited on an ITO substrate by three-step electrodeposition. The effect of ZnS layer deposition temperature on the properties of the heterojunction was investigated by different techniques. The Mott-Schottky analysis confirmed the n-type conductivity for ZnO and ZnS and p-type conductivity for the Cu 2 O layer, respectively. Also, it showed a decrease of ZnS donor concentration with increasing deposition temperature. The X-ray diffraction (XRD) analysis confirms a pure phase of hexagonal ZnO, cubic ZnS and cubic Cu 2 O structures, respectively. The heterojunction with ZnS deposited at 60 °C shows high crystallinity. The morphological measurements by scanning electron microscopy (SEM) indicate that the deposition temperature has a significant influence on the morphology of ZnO and the atomic force microscopy (AFM) images revealed the improvement of Cu 2 O morphology by increasing the ZnS deposition temperature. The UV-Vis response shows strong absorption in the visible region and the profile of optical absorption spectra changes with the ZnS deposition temperature. The current-voltage ( I - V ) characteristics of the Au/p-Cu 2 O/n-ZnO/n-ZnS/ITO heterojunction display well-defined rectifying behavior for the heterojunction with ZnS deposited at 60 °C., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The authors aimed to determine the prevalence of antineuronal antibodies in 103 psychiatric inpatients and 41 control subjects with no history of malignancies or neurological disorders. All sera were tested by indirect immunofluorescence and positive sera by immunoblot. Using immunofluorescence, antineuronal nuclear autoantibodies were detected in 20 patients and none of the control subjects, and antibodies reacted with the cytoplasm of Purkinje cells in six patients and two control subjects. The immunoblot confirmed well-characterized antineuronal antibodies only in five patients: two had anti-Ri and three had anti-Yo antibodies. After a follow-up of 5 years, none of these patients developed neurological disorder or malignancy.

The physiopathology of idiopathic achalasia is still unknown. The description of circulating antimyenteric autoantibodies (CAA), directed against enteric neurons in sera of patients, suggests an autoimmune process. Recent data showed controversies according to the existence and the significance of CAA. The aims of this study were to investigate whether CAA are detected in Tunisian patients with idiopathic achalasia and to look for associated clinical or manometrical factors with CAA positivity. Twenty-seven patients with idiopathic achalasia and 57 healthy controls were prospectively studied. CAA were assessed by indirect immunofluorescence on intestinal monkey tissue sections. Western blot on primate cerebellum protein extract and dot technique with highly purified recombinant neuronal antigens (Hu, Ri, and Yo) were further used to analyze target antigens of CAA. CAA were significantly increased in achalasia patients compared with controls when considering nuclear or cytoplasmic fluorescence patterns. (33% vs. 12%, P = 0.03 and 48% vs. 23%, P = 0.001 respectively). By immunoblot analysis, CAA did not target neuronal antigens, however 52/53 and 49 kDa bands were consistently detected. CAA positivity was not correlated to specific clinical features. The results are along with previous studies demonstrating high CAA prevalence in achalasia patients. When reviewing technical protocols and interpretation criteria, several discrepancies which could explain controversies between studies were noted., (© 2012 Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.)

Anti-cyclic citrullinated peptide antibodies (ACPA) seem to be produced locally at the site of joints inflammation in the first stage of rheumatoid arthritis (RA). A strong correlation between serum ACPA and ACPA in the synovial fluid (SF-ACPA) is now suggested. A case-control study was conducted to evaluate the usefulness of ACPA determination in SF of patients with RA. A total of 53 patients with a knee-joint effusion (26 RA, 18 peripheral spondyloarthropathies (SPA), and 9 osteoarthritis (OA)) were included in our study. SF samples were obtained by performing therapeutic arthrosynthesis. IgG serum ACPA and SF-ACPA levels were determined by the enzyme-linked immunosorbent assay (ELISA). We have also determined IgG levels in serum and SF by nephelometry. Higher levels of IgG ACPA antibodies in SF (p = 0.045) and serum (p = 0.045) were found in patients with RA with respect to SPA and OA patients. The Spearman correlation analysis showed a significant and positive correlation between ACPA in serum and SF (rho = 0.516; p = 0.007) not only in the RA group but also in patients with SPA. Serum ACPA discriminated RA from non-RA at a cut-off value of 2.7 U/ml (sensitivity, 69%; specificity, 78%; and area under the curve (AUC), 0.72), whereas SF-ACPA discriminated RA from non-RA at a higher cut-off value of 4.95 U/ml (sensitivity, 73%; specificity, 61%; and AUC, 0.71). Our study suggests that the determination of SF-ACPA give complement information to serum ACPA in patients with RA.

One hundred and three psychiatric inpatients (74 men) were assessed for a wide spectrum of autoantibodies including antinuclear, antismooth muscle, antimitochondrial, antiDNA, anti-phospholipid, anti-cardiolipin IgG and IgM, antikeratin, rheumatoid factor, antithyroperoxydase, antigliadin IgA and IgG, antitransgutaminase, and antiendomysium antibodies. Four groups of patients were considered separately, including 47 with schizophrenia, 23 with schizoaffective disorder, 16 with bipolar disorder and 17 patients with other different psychiatric diagnosis. Forty one healthy, age- and sex-matched blood donors were used as a control group. There were no significant difference in the prevalence of the different autoantibodies between patients (N = 103) and controls except for antigliadin IgG (30.1 vs 9.8 respectively, p = 0.01). Presence of autoantibodies was influenced by age but not by sex or treatment. As for diagnosis categories, patients with bipolar disorder presented significantly more autoantibodies than the three other categories and controls. These results point out a possible autoimmune activation in at least a subgroup of psychiatric patients especially amongst those suffering from bipolar disorder.

Background: Pemphigus is a life-threatening autoimmune blistering disease mediated by autoantibodies against adhesion molecule of the skin. Its concurrence with systemic and organ-specific autoimmune disease was described in case reports., Objectives: To evaluate the presence of a broad spectrum of organ-specific and non-organ-specific autoantibodies other than anti-desmoglein antibodies in pemphigus patients., Patients and Methods: Serum samples were obtained from 105 pemphigus foliaceus (PF) patients, 51 pemphigus vulgaris (PV) patients and 50 controls. Both indirect immunofluorescence assay and ELISA were used to assess the presence of autoantibodies related to connective tissue diseases, autoimmune hepatitis, vasculitis, rheumatoid arthritis, coeliac disease, diabetes and thyroiditis., Results: Significant difference was observed between the three groups for anti-thyroglobulin antibodies in the pemphigus foliaceus group (18% vs. 4%, P=0.03). A significantly higher occurrence of IgM anti-cardiolipin (P=0.03), IgG anti-reticulin (P=0.01) and IgG anti-gliadin antibodies (P=0.008) were observed in the PV group. Cases with more than four autoantibodies were frequently positives for both anti-desmoglein 1 and anti-desmoglein 3., Conclusion: Autoantibodies other than anti-desmoglein antibodies are not rare in pemphigus patients. Clinical and serological follow-up of pemphigus patients with positive autoantibodies are needed to clarify their impact in disease evolution., (© 2010 The Authors. Journal of the European Academy of Dermatology and Venereology © 2010 European Academy of Dermatology and Venereology.)

The objective of the study is to assess the distribution of HLA-B genes, HLA-B27 subtypes, HLA-DRB1 and HLA-DQB1 alleles in patients with ankylosing spondylitis (AS) and in control subjects in the Tunisian population and to compare their distribution with that found in other countries. This is a case-control study that included 100 consecutive patients (85 males/15 females) with AS according to the modified New York criteria and 100 control individuals. HLA-B, B27 subtypes and class II (DR and DQ) typing of all subjects was performed by polymerase chain reaction amplification with sequence-specific primers (PCR-SSP). HLA-B27 was found in 62% of patients against 3% in controls (P = 0.0000, OR = 52.6, 15.6 < CI < 166.7). On the other hand, B*07 and B*51 were significantly decreased in comparison with controls (P = 0.01, OR = 0.3, 0.1 < CI < 0.8 and P = 0.0000, OR = 0.2, 0.1 < CI < 0.4, respectively). Eight B*27 subtypes were identified in the AS group, but the most frequent ones were B*2702 (32%) and B*2705 (24%). Among HLA-DRB1 alleles, a significant increase in DRB1*11 was found in comparison with controls (P = 0.01, OR = 2.2, 1.2 < CI < 4.5). However, DRB1*13 had a negative association with AS (P = 0.01, OR = 0.4, 0.2 < CI < 0.8). For HLA-DQB1 alleles, a significant positive association with DQB1*03 was observed in AS group (P = 0.03, OR = 1.8, 1.0 < CI < 3.4). Multivariate analysis by logistic regression revealed that DRB1*11 and DQB1*03 had no direct links with the disease, but were dependent on the presence of HLA-B27. Moreover, B*07 and B*51 seemed to have independently a negative correlation with AS, but DRB1*13 seemed to depend on B*51. Haplotypes carrying B27 were significantly associated with AS and those carrying B*07 or B*51 were negatively correlated with the disease. In conclusion, our study confirms that B27 predisposes to AS while B*07 and B*51 are negatively correlated with the disease.