Synthesis and Characterization of Novel Sprayed Ag-Doped Quaternary Cu2MgSnS4 Thin Film for Antibacterial Application.

In this work, the effects of silver doping with different Ag/(Ag + Cu) ratios (i.e., 2%, 5% and 10% at.% in the spray solution) on the structural, morphological, optical, electrical and antibacterial properties of Cu2MgSnS4 (CMTS) thin film grown by spray pyrolysis have been studied. The X-ray diffraction (XRD) and selected area electron diffraction (SAED) results have shown that the kesterite phase of CMTS thin films has a maximum crystallite size of about 19.60 nm for 5% Ag/(Ag + Cu). Scanning electron microscopy (SEM) images have shown spherical grain shapes. The transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) microscopy observations confirmed the intrinsic reticular planes of CMTS thin film with (112) as a preferred orientation and interplanar spacing value of 3.1 Å. The optical properties showed high absorbance and an absorption coefficient of about 104 cm-1 in the visible region with an optical band gap energy of 1.51 eV. Impedance analysis spectroscopy demonstrated good electrical properties of the CMTS film obtained using 5% Ag/(Ag + Cu). The antibacterial activity of the undoped and Ag-doped particles of CMTS obtained using 5% Ag/(Ag + Cu) against different strains of pathogenic bacteria was tested using the agar well diffusion method. These results showed a significant antibacterial activity of the Ag-doped CMTS particle, which was much higher than the undoped CMTS particles. These experimental findings may open new practices for the Ag-doped CMTS compound, especially the one obtained using 5% Ag/(Ag + Cu), in antibacterial application.

Correction to: Relationship between Toxoplasma gondii seropositivity and schizophrenia in the Lebanese population: potential implication of genetic polymorphism of MMP-9.

An amendment to this paper has been published and can be accessed via the original article.

Relationship between Toxoplasma gondii seropositivity and schizophrenia in the Lebanese population: potential implication of genetic polymorphism of MMP-9.

BACKGROUND: Toxoplasma multiplication and its persistence into the brain cause a local neuroinflammatory reaction, resulting synthesis of neurotransmitters involved in neurological disorders, especially schizophrenia. The Matrix metallopeptidase 9 (MMP-9) protein can play a major role in this neuroinflammation. It can promote extravasation and migration of infected immune cells into the brain. The objectives of this study are to determine the possible association between schizophrenia and toxoplasmosis and highlight the existence of gene polymorphism encoding MMP-9 protein's in patients presented both schizophrenia and toxoplasmosis. METHODS: A case-control study was conducted on 150 patients with schizophrenia (case group), and 150 healthy persons (control group). Groups were matched with age, gender, and place of residence. The survey was conducted using a questionnaire and a serological profile assay for specific IgG and IgM antibodies against T. gondii. Reverse transcription-polymerase chain reaction (RT-PCR) of gene polymorphism encoding MMP-9 was performed on 83 cases selected randomly. RESULTS: Data show a significant association between toxoplasmosis (IgM+/IgG+ serological profile) and schizophrenia. Significant effects of raw meat consumption and contact with cats have been associated with the occurrence of schizophrenia. RT-PCR shows the presence of muted allele of MMP-9 gene in selected cases whose present T. gondii serological profile IgM+/IgG+ and IgM-/IgG+ respectively. CONCLUSION: Toxoplasmosis may be one of the etiological causes of schizophrenia, and MMP-9 gene polymorphism could be involved in the occurrence mechanism of this pathology following Toxoplasma infection.