Association between periodontal health and trait anxiety in Egyptian women: A cross-sectional study.

OBJECTIVES: This study explored the relationship between periodontal problems and trait anxiety in a sample of Egyptian women. MATERIALS AND METHODS: The Egyptian validated Arabic version of the State-Trait Anxiety Inventory-Trait subscale was used to measure levels of trait anxiety, and the periodontal health status of 451 Egyptian women was assessed using the Community Periodontal Index. Data were also collected on potential covariates such as age, educational level, marital status, parity, smoking, and oral healthcare-seeking behavior. Multivariate logistic regression analysis was done to evaluate the association between periodontal diseases and trait anxiety. RESULTS: Among study participants, and after adjusting for some of the potential confounders, trait anxiety exhibited weak association with periodontal diseases (OR: 1.11; 95% CI= 1.07, 1.14; p <0.001). Also, old age (OR: 1.12; 95% CI = 1.07, 1.17; p < 0.001) as well as parity (OR: 7.26; 95% CI = 2.89, 18.27; p <0.001) were significantly associated with periodontal problems in the adjusted model. CONCLUSION: While the study findings may implicate that personality traits, such as trait anxiety, could be linked to periodontal diseases more research is warranted to confirm or reject this association.

COVID-19 vaccine acceptance and perceptions among dental teaching staff of a governmental university in Egypt.

BACKGROUND: Vaccine acceptance among healthcare workers (HCWs) is an important determinant of its acceptance among the general population. Dentists are an essential group of HCWs who are at an increased risk of COVID-19 infection. This study aimed to assess vaccine acceptance and its determinants among a group of dental teaching staff in Egypt. METHODS: An Internet-based cross-sectional study was conducted where the dental teaching staff of a governmental university in Egypt were targeted using total population sampling. Data was collected on socio-demographics, attitudes towards COVID-19, risk perception, general attitudes towards vaccination, vaccine acceptance, and concerns about COVID-19 vaccines, along with barriers and motivators to vaccination. Multivariate regression was done to determine factors significantly associated with unwillingness to receive COVID-19 vaccine. RESULTS: A total of 171 dental faculty members participated in the study. At the time of data collection (August 2021-October 2021), 45.6% of the dental teaching staff were willing to receive the vaccine, while 46.7% were against vaccination, and 7.6% were vaccine hesitant. Female gender, not having a private practice, not intending to travel internationally, having anyone sick in the immediate social circle, and being more anxious about COVID-19 were significantly associated with unwillingness to receive the COVID-19 vaccine. CONCLUSION: At the time of conducting this study (August 2021-October 2021), less than half of the participating dental teaching staff in the studied Egyptian university were willing to receive the COVID-19 vaccine. Findings of the current study can guide Egyptian health authorities to adopt strategies that correct misconceptions among HCWs, educate them and build their trust in the efficacy and safety of COVID-19 vaccines, which can ultimately increase its acceptance in the general population.

Production of Superoxide in Bacteria Is Stress- and Cell State-Dependent: A Gating-Optimized Flow Cytometry Method that Minimizes ROS Measurement Artifacts with Fluorescent Dyes.

The role of reactive oxygen species (ROS) in microbial metabolism and stress response has emerged as a major theme in microbiology and infectious disease. Reactive fluorescent dyes have the potential to advance the study of ROS in the complex intracellular environment, especially for high-content and high-throughput analyses. However, current dye-based approaches to measuring intracellular ROS have the potential for significant artifacts. Here, we describe a robust platform for flow cytometric quantification of ROS in bacteria using fluorescent dyes, with ROS measurements in 10s-of-1000s of individual cells under a variety of conditions. False positives and variability among sample types (e.g., bacterial species, stress conditions) are reduced with a flexible four-step gating scheme that accounts for side- and forward-scattered light (morphological changes), background fluorescence, DNA content, and dye uptake to identify cells producing ROS. Using CellROX Green dye with Escherichia coli, Mycobacterium smegmatis, and Mycobacterium bovis BCG as diverse model bacteria, we show that (1) the generation of a quantifiable CellROX Green signal for superoxide, but not hydrogen peroxide-induced hydroxyl radicals, validates this dye as a superoxide detector; (2) the level of dye-detectable superoxide does not correlate with cytotoxicity or antibiotic sensitivity; (3) the non-replicating, antibiotic tolerant state of nutrient-deprived mycobacteria is associated with high levels of superoxide; and (4) antibiotic-induced production of superoxide is idiosyncratic with regard to both the species and the physiological state of the bacteria. We also show that the gating method is applicable to other fluorescent indicator dyes, such as the 5-carboxyfluorescein diacetate acetoxymethyl ester and 5-cyano-2,3-ditolyl tetrazolium chloride for cellular esterase and reductive respiratory activities, respectively. These results demonstrate that properly controlled flow cytometry coupled with fluorescent probes provides precise and accurate quantitative analysis of ROS generation and metabolic changes in stressed bacteria.

Inhibition of hepatitis C viral RNA-dependent RNA polymerase by α-P-boranophosphate nucleotides: exploring a potential strategy for mechanism-based HCV drug design.

Improved treatments for chronic HCV infections remain a challenge, and new chemical strategies are needed to expand the current paradigm. The HCV RNA polymerase (RdR(P)) has been a target for antiviral development. For the first time we show that the boranophosphate (BP) modification increases the substrate efficiency of ATP analogs into HCV NS5BΔ55 RdRP-catalyzed RNA. Boranophosphate nucleotides contain a borane (BH3) group substituted for a non-bridging phosphoryl oxygen of a normal phosphate group, resulting in a class of modified isoelectronic DNA and RNA mimics capable of modulating the reading and writing of genetic information. We determine that HCV NS5BΔ55, being a stereospecific enzyme, incorporates the Rp isomer of both ATPαB and the two boranophosphate analogs: 2'-O-methyladenosine 5'-(α-P-borano) triphosphate (2'-OMe ATPαB, 5a) and 3'-deoxyadenosine 5'-(α-P-borano) triphosphate (3'-dATPαB, 5b). The R(p) diastereomer of ATPαB (6), having no ribose modifications, was found to be a slightly better substrate than natural ATP, showing a 42% decrease in the apparent Michaelis-Menten constant (K(m)). The IC50 of both 2'-O-Me and 3'-deoxy ATP was decreased with the boranophosphate modification up to 16-fold. This "borano effect" was further confirmed by determining the steady-state inhibitory constant (K(i)), showing a comparable potency shift (21-fold). These experiments also indicate that the boranophosphate analogs 5a and 5b inhibit HCV NS5B through a competitive mode of inhibition. This evidence, together with previous crystal structure data, further supports the idea that HCV NS5B (in a similar manner to HIV-1 RT) discriminates against the 3'-deoxy modification via lost interactions between the 3'-OH on the ribose and the active site residues, or lost intramolecular hydrogen bonding interactions between the 3'-OH and the pyrophosphate leaving group during phosphoryl transfer. To our knowledge, these data represent the first time a phosphate modified NTP has been studied as a substrate for HCV NS5B RdRP.

Aptamer-mediated delivery of chemotherapy to pancreatic cancer cells.

Gemcitabine is a nucleoside analog that is currently the best available single-agent chemotherapeutic drug for pancreatic cancer. However, efficacy is limited by our inability to deliver sufficient active metabolite into cancer cells without toxic effects on normal tissues. Targeted delivery of gemcitabine into cancer cells could maximize effectiveness and concurrently minimize toxic side effects by reducing uptake into normal cells. Most pancreatic cancers overexpress epidermal growth factor receptor (EGFR), a trans-membrane receptor tyrosine kinase. We utilized a nuclease resistant RNA aptamer that binds and is internalized by EGFR on pancreatic cancer cells to deliver gemcitabine-containing polymers into EGFR-expressing cells and inhibit cell proliferation in vitro. This approach to cell type-specific therapy can be adapted to other targets and to other types of therapeutic cargo.

Boranophosphate siRNA-aptamer chimeras for tumor-specific downregulation of cancer receptors and modulators.

There is a need for novel, effective, and cell- and gene-specific therapeutics for cancer. Modified oligonucleotides can be used to modulate specifically and potently the expression of several genes that are upregulated in breast and prostate cancer and have been found to be causal to the tumor phenotype. Synergistic downregulation of these genes may be a potent therapeutic intervention. We are investigating the use of boranophosphate (BP) analogues of RNA as promising candidates for enhancing the potential of three relatively new, gene-specific, anticancer strategies: (1) Tumor-targeted borane siRNA against a combination of genes that control metabolism and transduction; (2) Tumor-specific modified aptamers against prostate specific membrane antigen (PSMA) and ERB2 in breast cancer as delivery agents; and (3) Cancer cell obliteration by cell-specific radiation therapy: Boron-Neutron-Capture-Therapy.