Outer membrane protein size and LPS O-antigen define protective antibody targeting to the Salmonella surface

Lipopolysaccharide (LPS) O-antigen (O-Ag) is known to limit antibody binding to surface antigens, although the relationship between antibody, O-Ag and other outer-membrane antigens is poorly understood. Here we report, immunization with the trimeric porin OmpD from Salmonella Typhimurium (STmOmpD) protects against infection. Atomistic molecular dynamics simulations indicate this is because OmpD trimers generate footprints within the O-Ag layer sufficiently sized for a single IgG Fab to access. While STmOmpD differs from its orthologue in S. Enteritidis (SEn) by a single amino-acid residue, immunization with STmOmpD confers minimal protection to SEn. This is due to the OmpD-O-Ag interplay restricting IgG binding, with the pairing of OmpD with its native O-Ag being essential for optimal protection after immunization. Thus, both the chemical and physical structure of O-Ag are key for the presentation of specific epitopes within proteinaceous surface-antigens. This enhances combinatorial antigenic diversity in Gram-negative bacteria, while reducing associated fitness costs

Benchmarking the scientific output of industrial wastewater research in Arab world by utilizing bibliometric techniques

Rapid population growth, worsening of the climate, and severity of freshwater scarcity are global challenges. In Arab world countries, where water resources are becoming increasingly scarce, the recycling of industrial wastewater could improve the efficiency of freshwater use. The benchmarking of scientific output of industrial wastewater research in the Arab world is an initiative that could support in shaping up and improving future research activities. This study assesses the scientific output of industrial wastewater research in the Arab world. A total of 2032 documents related to industrial wastewater were retrieved from 152 journals indexed in the Scopus databases; this represents 3.6 % of the global research output. The h-index of the retrieved documents was 70. The total number of citations, at the time of data analysis, was 34,296 with an average citation of 16.88 per document. Egypt, with a total publications of 655 (32.2 %), was ranked the first among the Arab countries followed by Saudi Arabia 300 (14.7 %) and Tunisia 297 (14.6 %). Egypt also had the highest h-index, assumed with Saudi Arabia, the first place in collaboration with other countries. Seven hundred fifteen (35.2 %) documents with 66 countries in Arab/non-Arab country collaborations were identified. Arab researchers collaborated mostly with researchers from France 239 (11.7 %), followed by the USA 127 (6.2 %). The top active journal was Desalination 126 (6.2 %), and the most productive institution was the National Research Center, Egypt 169 (8.3 %), followed by the King Abdul-Aziz University, Saudi Arabia 75 (3.7 %). Environmental Science was the most prevalent field of interest 930 (45.8 %). Despite the promising indicators, there is a need to close the gap in research between the Arab world and the other nations. Optimizing the investments and developing regional experiences are key factors to promote the scientific research

Educators’ Readiness in Supporting Dental Students’ Mental Health: A Cross-Sectional Study

Maan Alsultan,1 Abrar Tounsi,2 Alhanouf Alnowaiser,3 Jawaher Alseneidi,3 Eman Alshayea1 1Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia; 2Department of Periodontics and Community Dentistry, College of Dentistry, King Saud University, Riyadh, Saudi Arabia; 3College of Dentistry, King Saud University, Riyadh, Saudi ArabiaCorrespondence: Abrar Tounsi, Department of Periodontics and Community Dentistry, College of Dentistry, King Saud University, PJ8C+3HH, Riyadh, Saudi Arabia, Email [email protected]: The mental health of dental undergraduates can significantly influence their overall well-being. Educators can be pivotal in identifying various mental health concerns. The aim of this study was to assess knowledge, experience, self-efficacy, and attitude of dental educators regarding the mental health of their students.Methods: A cross-sectional study involving a convenient sample was conducted on a group of faculty members from different dental schools in Riyadh Region. A validated self-administered online survey was carried out between June and August 2022.Results: A total of 80 faculty members participated in the study. A high percentage of participants were knowledgeable about the effect of mental health on students’ academic performance and retention (72.5%). About 56.3% of educators did not receive previous preparation to deal with students’ mental health issues, and 50% faced cases of mental health issues among their students. Even though 40% were not confident in their knowledge about mental health issues, the majority 85% agreed that getting a course on mental health issues and how to deal with them is crucial.Conclusion: The findings of this study indicate that while dental educators generally understand the impact of mental health on students’ academic performance, they face notable gaps in preparedness and confidence. Key barriers include insufficient training, limited awareness of institutional resources, and difficulties in accessing mental health information. These results emphasize the need to equip educators with the necessary knowledge and resources to effectively support students’ mental well-being.Keywords: students, dental, burnout, psychological, school mental health service

Efficacy of Different Tooth Lining Materials on Marginal Seal of Composite Restorations Extended upto Root Surface of the Tooth- Systematic Review

Introduction: Microleakage is a major concern in composite restorations, especially with margins located on dentin or cementum of the tooth. This study aimed to review the available literature investigating in vitro the efficacy of different tooth lining materials on the marginal seal of composite restorations extended below the Cemento-Enamel Junction (CEJ) of the tooth.&#x0D; Materials and Methods: Different combinations of the review terms were used to electronically search PubMed, Google Scholar, Cochrane Library, and Ebscohost databases for the last fifteen years. The records were initially screened for relevancy based on title and abstract. Articles that seemed to meet the criteria for inclusion were selected for full-text assessment.  Studies deemed eligible were in vitro studies conducted on human teeth with cavities extending below the CEJ and restored using different tooth lining materials under the composite restorations.Every included study was evaluated using the Cochrane risk of bias assessment tool.&#x0D; Results: The initial search identified 619 publications. After removing duplicated records, the remaining 421 records are screened at the level of titles and abstracts to meet our inclusion criteria. 62 records were designated for full-text methodological assessment, and 15 studies were found eligible for qualitative synthesis. The sealing ability of different tooth lining materials under composite restorations was investigated in the chosen studies, with varying outcomes. Microleakage in the tooth restorations was determined by examining the extent of dye penetration under a microscope.&#x0D; Conclusion: Despite the reports of less dye penetration with specific tooth liners in some in-vitro studies, there is no consistent evidence supporting that such tooth liners could reduce microleakage in composite restorations of the tooth.</jats:p

Validation and psychometric testing of the Arabic version of the mental health literacy scale among the Saudi Arabian general population

Abstract Objective This study aimed to validate the Arabic Version of the Mental Health Literacy Scale (Arabic-MHLS) among the Saudi Arabian general population, assessing its internal consistency, test-retest reliability, and structural validity. Methods A total of 700 Arabic-speaking Saudi adults were randomly selected to complete the electronic questionnaire in May 2023, which generated 544 participants. Data were coded and stored in the ZdataCloud research data collection system database. Test-retest reliability was assessed using a subsample of 48 participants who completed the questionnaire twice, with a one-week interval. Structural validity was examined using confirmatory factor analysis (CFA) and Exploratory Factor Analysis (EFA). Results The Arabic-MHLS demonstrated good internal consistency (Cronbach’s alpha = 0.87) and test-retest reliability (intraclass correlation coefficient = 0.89). EFA revealed a four-factor model closely resembling the model identified in the Slovenian validation of MHLS, with factor loadings ranging from 0.40 to 0.85. The four factors included knowledge of mental health disorders, knowledge of help-seeking, knowledge of self-help strategies, and knowledge of professional help also showed good internal consistency. Conclusion The Arabic-MHLS is a valid and reliable tool for assessing mental health literacy in the Saudi Arabian general population. However, further research is needed to refine the measurement tool and understand the complex relationships between mental health literacy and other mental health-related concepts. This will contribute to the development of targeted interventions and policies aimed at improving mental health literacy and promoting mental well-being in the Saudi Arabian population and beyond

Outer membrane protein size and LPS O-antigen define protective antibody targeting to the Salmonella surface

AbstractLipopolysaccharide (LPS) O-antigen (O-Ag) is known to limit antibody binding to surface antigens, although the relationship between antibody, O-Ag and other outer-membrane antigens is poorly understood. Here we report, immunization with the trimeric porin OmpD from Salmonella Typhimurium (STmOmpD) protects against infection. Atomistic molecular dynamics simulations indicate this is because OmpD trimers generate footprints within the O-Ag layer sufficiently sized for a single IgG Fab to access. While STmOmpD differs from its orthologue in S. Enteritidis (SEn) by a single amino-acid residue, immunization with STmOmpD confers minimal protection to SEn. This is due to the OmpD-O-Ag interplay restricting IgG binding, with the pairing of OmpD with its native O-Ag being essential for optimal protection after immunization. Thus, both the chemical and physical structure of O-Ag are key for the presentation of specific epitopes within proteinaceous surface-antigens. This enhances combinatorial antigenic diversity in Gram-negative bacteria, while reducing associated fitness costs.</jats:p

Outer membrane protein size and LPS O-antigen define protective antibody targeting to the Salmonella surface

Lipopolysaccharide (LPS) O-antigen (O-Ag) is known to limit antibody binding to surface antigens, although the relationship between antibody, O-Ag and other outer-membrane antigens is poorly understood. Here we report, immunization with the trimeric porin OmpD from Salmonella Typhimurium (STmOmpD) protects against infection. Atomistic molecular dynamics simulations indicate this is because OmpD trimers generate footprints within the O-Ag layer sufficiently sized for a single IgG Fab to access. While STmOmpD differs from its orthologue in S. Enteritidis (SEn) by a single amino-acid residue, immunization with STmOmpD confers minimal protection to SEn. This is due to the OmpD-O-Ag interplay restricting IgG binding, with the pairing of OmpD with its native O-Ag being essential for optimal protection after immunization. Thus, both the chemical and physical structure of O-Ag are key for the presentation of specific epitopes within proteinaceous surface-antigens. This enhances combinatorial antigenic diversity in Gram-negative bacteria, while reducing associated fitness costs