Nanoparticle Augmentation of Adhesive Systems: Impact on Tensile Strength in Fiberglass Post Placement within Root Dentin.

BACKGROUND Modification of the glass fiber post (GFP) with titanium dioxide or silver particles can improve the durability and reliability of dental treatments for ensuring long-term success. This research assessed the tensile bond strength (TBS) of an adhesive system used for cementing GFPs into root dentin following the incorporation of nanoparticles of titanium dioxide (NTiO2) and silver (NAg). MATERIAL AND METHODS Sixty human maxillary canines were prepared to create a 10-mm intra-radicular space for post placement from the cementoenamel junction. The specimens were randomly allocated into 2 groups (a non-thermocycling group and a thermocycling group). Each group was divided into 3 subgroups (10 samples each) according to the adhesive system used (adhesive system devoid of any addition, adhesive system including 1% NAg, and adhesive system infused with 1% NTiO2). TBS tests were conducted and recorded in MPa using a Universal Testing Machine, with an axial load applied at a rate of 0.5 mm/min until failure. The TBS for both groups (non-thermocycling and thermocycling) was measured in megapascals (MPa), and the failure type was recorded. The data were statistically analyzed using one-way analysis of variance (ANOVA) and Tukey's test with P.

The risks of artificial intelligence: A narrative review and ethical reflection from an Oral Medicine group.

As a relatively new tool, the use of artificial intelligence (AI) in medicine and dentistry has the potential to significantly transform the healthcare sector. AI has already demonstrated efficacy in medical diagnosis across several specialties, used successfully to detect breast, lung and skin cancer. In Oral Medicine, AI may be applied in a similar fashion, used in the detection and diagnosis of oral cancers and oral potentially malignant diseases. Despite its promise as a transformative diagnostic aid, the use of AI in healthcare presents significant safety, reliability and ethical concerns. There is no formal consensus on the safe and ethical implementation of AI systems in healthcare settings, but the literature converges on several key principles of ethical AI use including transparency, justice and fairness, non-maleficence, responsibility and privacy. This article provides a narrative review of the key ethical issues surrounding AI use in medicine, and reflects on these, providing view-points of a bioethicist and Oral Medicine clinicians from several units.

Methylene blue-assisted molecularly-imprinted film modified nitrogen and sulfur co-doped molybdenum carbide for simultaneous electrochemical determination of two hepatotoxic drugs.

A novel electrochemical sensor with a dual-template molecular imprinting technology was fabricated for the simultaneous detection of paracetamol (PAR) and isoniazid (INZ). The sensor was constructed using nitrogen and sulfur co-doped molybdenum carbide (N, S@Mo2C) and a thin layer of electro-polymerized methylene blue was applied onto the surface of the N, S@Mo2C. The electrochemical sensor demonstrated remarkable analytical efficiency for the concurrent PAR and INZ quantification under optimal circumstances. The system achieved an exceptionally low limit of detection (S/N = 3) of  3.7 nM for PAR, with a concentration range  of  0.013 and 140 µM.  A LOD of 7.6 nM was attained for INZ, with a linear range  between 0.025 and 140 µM. Furthermore, the platform's selectivity was evaluated using differential pulse voltammetry  (DPV). The designed platform successfully detected PAR and INZ in authentic samples with recoveries varying between 98.3% and 104.9%. The relative standard deviations (RSD) for these measurements ranged from 2.7 to 4.0%, demonstrating that the proposed sensor is extremely stable, repeatable, and reproducible. These promising results suggest that the sensor holds potential for the detection of various (bio) molecules, paving the way for future applications in sensing fields.

Ratiometric fluorometric determination of sulfide using graphene quantum dots and self-assembled thiolate-capped gold nanoclusters triggered by aluminum.

A ratiometric-based fluorescence emission system was proposed for the determination of sulfide. It consists of blue emissive graphene quantum dots (GQDs) and self-assembled thiolate-protected gold nanoclusters driven by aluminum ion (Al3+@GSH-AuNCs). The two types of fluorophores are combined to form a ratiometric emission probe. The orange emission of Al3+ @GSH-AuNCs at 624 nm was quenched in the presence of sulfide ion owing to the strong affinity between sulfide and Au(I), while the blue GQDs fluorescence at 470 nm remained unaffected. Interestingly, the Al3+@GSH-AuNCs and GQDs were excited under the same excitation wavelength (335 nm). The response ratios (F470/F624) are linearly proportional to the sulfide concentration within the linear range of 0.02-200 µM under the optimal settings, with a limit of detection (S/N = 3) of 0.0064 µM. The proposed emission probe was applied to detect sulfide ions in tap water and wastewater specimens, with recoveries ranging from 95.3% to 103.3% and RSD% ranging from 2.3% to 3.4%, supporting the proposed method's accuracy.

The effect of therapeutic footwear on the recurrence and new formation of foot ulcers in previously affected diabetic patients in Jeddah, Saudi Arabia.

AIM: Diabetic foot ulcers (DFUs), which are a common serious complication of diabetes mellitus, (lifetime occurrence, 19%-34%) account for at least 85% of all lower-limb amputations in diabetic patients. Special footwear (therapeutic footwear) is frequently recommended for such patients to adapt to changes in their foot structure. We aimed to, measure the effect of therapeutic footwear on DFU development and recurrence among previously affected patients in Saudi Arabia. MATERIALS AND METHODS: A cross-sectional study was performed between June and September 2022. The study targeted patients aged ≥18 years previously diagnosed with DFU. Participants were contacted by telephone to complete a questionnaire assessing footwear use and foot care. RESULTS: This study included 115 participants with a mean age of 61.9 ± 11.63; overall, 47% of participants used therapeutic footwear and 46% were adherent with wearing it. The DFU recurrence rate among patients who used therapeutic footwear was 27.8% versus 52.5% among patients who did not (p = 0.013). While using therapeutic footwear, patients with foot deformities reported a lower ulcer healing rate than those who did not (50% vs. 81.8%, p = 0.04). Patients who examined their feet had a lower recurrence rate than those who did not (38.5% vs. 50%, p = 0.43). CONCLUSION: Therapeutic footwear use was significantly associated with decreased DFU recurrence. Further investigation to enhance the evidence for the effectiveness of therapeutic footwear in DFUs is warranted.

Juglone from Walnut Produces Cardioprotective Effects against Isoproterenol-Induced Myocardial Injury in SD Rats.

Therapeutic and/or preventive interventions using phytochemical constituents for ischemic heart disease have gained considerable attention worldwide, mainly due to their antioxidant activity. This study investigated the cardioprotective effect and possible mechanism of juglone, a major constituent of the walnut tree, using an isoproterenol (ISO)-induced myocardial infarction (MI) model in rats. Rats were pretreated for five (5) days with juglone (1, 3 mg/kg, i.p) and atenolol (1 mg/kg, i.p) in separate experiments before inducing myocardial injury by administration of ISO (80 mg/kg, s.c) at an interval of 24 h for 2 consecutive days (4th and 5th day). The cardioprotective effect of juglone was confirmed through a lead II electrocardiograph (ECG), cardiac biomarkers (cTnI, CPK, CK-MB, LDH, ALT and AST) and histopathological study. The results of our present study suggest that prior administration of juglone (1 and 3 mg/kg) proved to be effective as a cardioprotective therapeutic agent in reducing the extent of myocardial damage (induced by ISO) by fortifying the myocardial cell membrane, preventing elevated T-waves, deep Q-waves in the ECG, heart to body weight ratio, infarction and also by normalizing cardiac marker enzymes (cTnI, CPK, CK-MB, LDH, ALT and AST) and histopathological changes, such as inflammation, edema and necrosis. In conclusion, this study has identified phytochemical constituents, in particular juglone, as a potential cardioprotective agent.

Extracellular ATP targets Arabidopsis RIBONUCLEASE 1 to suppress mycotoxin stress-induced cell death.

Extracellular ATP is a purinergic signal with important functions in regulating plant growth and stress-adaptive responses, including programmed cell death. While signalling events proximate to receptor activation at the plasma membrane have been characterised, downstream protein targets and the mechanism of cell death activation/regulation are unknown. We designed a proteomic screen to identify ATP-responsive proteins in Arabidopsis cell cultures exposed to mycotoxin stress via fumonisin B1 (FB1) application. Arabidopsis RIBONUCLEASE 1 (RNS1) was identified by the screen, and transgenic plants overexpressing native RNS1 showed greater susceptibility to FB1, while a gene knockout rns1 mutant and antisense RNS1 transgenic plants were resistant to FB1-induced cell death. Native RNS1 complemented rns1 mutants and restored the cell death response to FB1, while a catalytically inactive version of the ribonuclease could not. The FB1 resistance of salicylic acid (SA)-depleted nahG-expressing plants was abolished by transformation with native RNS1, but not the catalytically dead version. The mechanism of FB1-induced cell death is activation of RNS1-dependent RNA cleavage, which is blocked by ATP via RNS1 suppression, or enhanced by SA through induction of RNS1 expression. Our study reveals RNS1 as a previously unknown convergence point of ATP and SA signalling in the regulation of stress-induced cell death.

Toroidal nuclei of columnar lyotropic chromonic liquid crystals coexisting with an isotropic phase.

Nuclei of ordered materials emerging from the isotropic state usually show a shape topologically equivalent to a sphere; the well-known examples are crystals and nematic liquid crystal droplets. In this work, we explore experimentally and theoretically the toroidal in shape nuclei of columnar lyotropic chromonic liquid crystals coexisting with the isotropic phase. The geometry of these toroids depends strongly on concentrations of the disodium cromoglycate (DSCG) and the crowding agent, polyethylene glycol (PEG). High concentrations of DSCG and PEG result in thick toroids with small central holes, while low concentrations yield thin toroids with wide holes. The multitude of the observed shapes is explained by the balance of bending elasticity and anisotropic interfacial tension.

Primary hyperparathyroidism in Saudi Arabia revisited: a multi-centre observational study.

PURPOSE: Primary hyperparathyroidism (PHPT) is a common cause of hypercalcemia and remains understudied within the Arabian population. The present study, the largest of its kind within the Gulf Cooperation Council (GCC) countries, aims to determine the demographics and clinical presentation of PHPT in Saudi Arabia. METHODS: In this multi-center retrospective study involving three tertiary hospitals in different geographic locations of Saudi Arabia namely, Riyadh, Al Ahsa and Jeddah, a total of 205 out of 243 confirmed PHPT cases aged 16 to 93 years old were included (N = 96 from Riyadh; N = 59 from Al Ahsa and N = 50 from Jeddah). Demographics, clinical manifestations and surgical outcomes were recorded as well as laboratory and radiologic investigations including serum parathyroid hormone (PTH), 25(OH)D, adjusted calcium, estimated glomerular filtration rate (eGFR) and nuclear scan outcome. RESULTS: PHPT cases appeared to increase over time when compared to other local studies published so far, with 12.8 cases per 100,000 hospital population. Females outnumber males (3:1) with 86% seen as out-patients. The average age was 59.8 ± 15.5 years. Abnormal PTH scan was seen in 171 patients (83.4%). Kidney stones was the most common renal manifestation (32 cases, 15.6%) and osteoporosis was the most common skeletal manifestation (67 cases, 32.7%). Al Ahsa had the highest prevalence of multiple comorbidities at 54% and the highest prevalence of obesity as a single comorbidity (17%) compared to other regions (p < 0.05). Jeddah recorded the highest prevalence of osteoporosis with bone and joint pains (30%) (p < 0.05). CONCLUSION: Comparison of present data with previous local studies suggest an increasing trend in PHPT cases in Saudi Arabia. Regional variations in the clinical presentation of PHPT were observed and warrant further investigation.

Aspergillus ochraceus: Metabolites, Bioactivities, Biosynthesis, and Biotechnological Potential.

Fungus continues to attract great attention as a promising pool of biometabolites. Aspergillus ochraceus Wilh (Aspergillaceae) has established its capacity to biosynthesize a myriad of metabolites belonging to different chemical classes, such as isocoumarins, pyrazines, sterols, indole alkaloids, diketopiperazines, polyketides, peptides, quinones, polyketides, and sesquiterpenoids, revealing various bioactivities that are antimicrobial, cytotoxic, antiviral, anti-inflammatory, insecticidal, and neuroprotective. Additionally, A. ochraceus produces a variety of enzymes that could have variable industrial and biotechnological applications. From 1965 until June 2022, 165 metabolites were reported from A. ochraceus isolated from different sources. In this review, the formerly separated metabolites from A. ochraceus, including their bioactivities and biosynthesis, in addition, the industrial and biotechnological potential of A. ochraceus are highlighted.

Advances in Fungal Phenaloenones-Natural Metabolites with Great Promise: Biosynthesis, Bioactivities, and an In Silico Evaluation of Their Potential as Human Glucose Transporter 1 Inhibitors.

Phenaloenones are structurally unique aromatic polyketides that have been reported in both microbial and plant sources. They possess a hydroxy perinaphthenone three-fused-ring system and exhibit diverse bioactivities, such as cytotoxic, antimicrobial, antioxidant, and anti-HIV properties, and tyrosinase, α-glucosidase, lipase, AchE (acetylcholinesterase), indoleamine 2,3-dioxygenase 1, angiotensin-I-converting enzyme, and tyrosine phosphatase inhibition. Moreover, they have a rich nucleophilic nucleus that has inspired many chemists and biologists to synthesize more of these related derivatives. The current review provides an overview of the reported phenalenones with a fungal origin, including their structures, sources, biosynthesis, and bioactivities. Moreover, more than 135 metabolites have been listed, and 71 references have been cited. SuperPred, an artificial intelligence (AI) webserver, was used to predict the potential targets for selected phenalenones. Among these targets, we chose human glucose transporter 1 (hGLUT1) for an extensive in silico study, as it shows high probability and model accuracy. Among them, aspergillussanones C (60) and G (60) possessed the highest negative docking scores of -15.082 and -14.829 kcal/mol, respectively, compared to the native inhibitor of 5RE (score: -11.206 kcal/mol). The MD (molecular dynamics) simulation revealed their stability in complexes with GLUT1 at 100 ns. The virtual screening study results open up a new therapeutic approach by using some phenalenones as hGLUT1 inhibitors, which might be a potential target for cancer therapy.

Natural Reno-Protective Agents against Cyclosporine A-Induced Nephrotoxicity: An Overview.

CA (cyclosporine A) is a powerful immunosuppressing agent that is commonly utilized for treating various autoimmune illnesses and in transplantation surgery. However, its usage has been significantly restricted because of its unwanted effects, including nephrotoxicity. The pathophysiology of CA-induced kidney injury involves inflammation, apoptosis, tubular injury, oxidative stress, and vascular injury. Despite the fact that exact mechanism accountable for CA's effects is inadequately understood, ROS (reactive oxygen species) involvement has been widely proposed. At present, there are no efficient methods or drugs for treating CA-caused kidney damage. It is noteworthy that diverse natural products have been investigated both in vivo and in-vitro for their possible preventive potential in CA-produced nephrotoxicity. Various extracts and natural metabolites have been found to possess a remarkable potential for restoring CA-produced renal damage and oxidative stress alterations via their anti-apoptosis, anti-inflammatory, and antioxidative potentials. The present article reviews the reported studies that assess the protective capacity of natural products, as well as dietary regimens, in relation to CA-induced nephrotoxicity. Thus, the present study presents novel ideas for designing and developing more efficient prophylactic or remedial strategies versus CA passive influences.

Tailoring the substitution pattern of Pyrrolidine-2,5-dione for discovery of new structural template for dual COX/LOX inhibition.

Dual inhibition of the enzymatic pathways of cyclooxygenases (COX-1/COX-2) and lipoxygenase (LOX) is a rational approach for developing more efficient and safe anti-inflammatory agents. Herein, dual inhibitors of COX and LOX for the management of inflammation are reported. The structural modifications of starting pyrrolidine-2,5-dione aldehyde derivatives resulted in two structurally diverse families (Family A & B). Synthesized derivatives from both Families displayed preferential COX-2 affinity in submicromolar to nanomolar ranges. Disubstitution pattern of the most active series of compounds having N-(benzyl(4-methoxyphenyl)amino moiety presents a new template that is mimic to the diaryl pattern of traditional COX-2 inhibitors. Compound 78 with IC50 value of 0.051 ± 0.001 µM emerged as the most active compound. Highly potent COX-2/5-LOX inhibitors have also demonstrated appreciable in-vivo anti-inflammatory activity through carrageenan induced paw edema test. Moreover, the involvement of histamine, bradykinin, prostaglandin, and leukotriene mediators to adjust the inflammatory response were also studied. Apart from COX inhibition, sulfonamide is considered an important template for carbonic anhydrase inhibition. Hence, we also evaluated six sulfonamide derivatives for off-target in-vitro bovine carbonic anhydrase-II inhibition. Biological results were finally rationalized by docking simulations. Typically, most active COX-2 inhibitors interact with the amino acid residues responsible for the COX-2 selectivity.

Facile one pot sonochemical synthesis of layered nanostructure of ZnS NPs/rGO nanosheets for simultaneous analysis of daclatasvir and hydroxychloroquine.

In this study, zinc sulfide nanoparticles were loaded on reduced graphene oxide (ZnS NPs/rGO) using simple sonochemical method. The nanocomposite was characterized using different morphological and electrochemical techniques such as TEM, SEM, PXRD, EDX, Raman spectroscopy, FTIR, N2-adsorption-desorption, CV, and EIS. The ZnS NPs/rGO modified glassy carbon electrode (GCE) was used to simultaneously estimate hydroxychloroquine (HCQ) and daclatasvir (DAC) in a binary mixture for the first time. The modified nanocomposite exhibited good catalytic activity towards HCQ and DAC detection. In addition, it showed higher sensitivity, good selectivity and stability; and high reproducibility towards HCQ and DAC analysis. The activity of the modified electrode was noticeably improved due to synergism between ZnS NPs and rGO. Under optimum conditions of DPV measurements, the anodic peak currents (Ipa) were obviously increased with the increase of HCQ and DAC amounts with linear ranges of 5.0-65.0 and 7.0-65.0 nM with LODs of 0.456 and 0.498 nM for HCQ and DAC, respectively. The ZnS NPs/ rGO modified GCE was used to quantify HCQ and DAC in biological fluids with recoveries of 98.7-102.7% and 96.9-104.5% and RSDs of 1.89-3.57% and 1.91-3.70%, respectively.

Evaluation of phytochemical, anti-oxidant and cardiac depressant effect of Rumex dentatus by using Langendorff's isolated heart apparatus.

Rumex dentatus has been used traditionally for ailment of cardiovascular diseases. The aim of the present study was to assess cardiovascular effects in isolated perfused rabbit heart. Aqueous and n-butanolic fractions were assessed for their effect on perfusion pressure (PP), force of contraction (FC) and heart rate (HR) of rabbit heart using Langendorff's method. The possible mechanisms of action of extracts/fraction were assessed with and without application of different agonist/antagonist. Phytochemical, toxicity and anti-oxidant activities were also determined. Both extracts at 1mg/mL dose produced a highly significant decrease in FC and HR but PP remained unchanged. Moreover, aqueous fraction of Rumex dentatus at 0.001mg/mL dose produced a highly significant decrease in FC and HR but no significant change in PP was observed. Atropine 10-5 M did not inhibit the cardiac depressant response of both fractions. Furthermore, both fractions blocked the positive ionotropic and chronotropic effects of adrenaline and calcium chloride. Phytochemical studies have shown the presence of some phytochemicals. Acute and sub-chronic toxicity studies demonstrated that test extracts are safe and produced no significant changes in haematological and biochemical parameters. Crude extract showed significant antioxidant activity like ascorbic acid. This study revealed that this plant have good cardiac depressant effect.

Antihypertensive and safety studies of Cydonia oblonga M.

Antihypertensive studies on aqueous-methanolic extract prepared from seeds of Cydonia oblonga M. were carried out. The test extract in 200, 400 and 600 mg/kg doses was investigated in normotensive, high cholesterol and glucose fed hypertensive rats through non-invasive blood pressure measuring technique. Acute and sub-chronic toxicity studies were conducted in mice and rats, respectively. The test extract significantly decreased dose dependently the systolic, diastolic and mean arterial pressures. The test extract in 600mg/kg dose produced maximum effect and prevented rise in blood pressure of high cholesterol diet and glucose fed rats as compare to control in 21 days studies. The extract was found safe up to 4g/kg dose in mice. In sub-chronic toxicity study, no significant alteration in blood chemistry of extract treated rats was observed except reduction in the low density cholesterol levels. It is concluded that Cydonia oblonga seeds extract possess antihypertensive effect which supports its use in folklore.

Appraisal of hypotensive effect of natural monoterpene: Bornyl acetate and in-silico molecular docking analysis.

The modern trend of research is highly focused on finding new bioactive molecules from medicinal plants. As a functional bicyclic monoterpene, Bornyl acetate (BA) has displayed antioxidant and anti-inflammatory properties in different types of cells and tissues. The purpose of this research was to evaluate the probable hypotensive effect of BA, an underlying mechanism(s) backboned by in-silico studies. Mean arterial pressure and heart rate were recorded via invasive blood pressure measuring technique in normotensive Sprague-Dawley rats following the administration of BA (1-80mg/kg). Docking studies were carried out with various targets involved in the pathophysiology of hypertension.RO5 and ADMET properties were also evaluated. In the current study dose-dependent reduction in systolic, diastolic and mean arterial pressure was observed. Pretreatment with atropine and captopril significantly (p<0.001) reduced the hypotensive effect produced by BA. On the other hand docking studies showed pronounced interactions with M2 mAch receptor in an agonistic way and ACE protein in an antagonistic way. BA justified all cut-off limits of RO5 and had an acceptable predicted computational toxicity profile. Results postulate that dose-dependent hypotensive effect of BA is mediated through the muscarinic pathway and ACE inhibitory activity corresponding well with findings of in-silico studies.

Endothelium independent calcium channel blocking pathways mediate antihypertensive effect of morus nigra.

Present study was conducted to validate the folkloric claims of morus nigra l. (moraceae) using invasive blood pressure measuring and ex vivo vasorelaxant experimental techniques. Intravenous administration of mn. Aq in 0.01-30 mg/kg doses caused significant decrease in mean arterial pressure and heart rate in fructose-induced hypertensive rats. It also showed relaxation in high k+ [80 mm] and pe (1µm) mediated aortic contraction with ec50 1.25 and 3.72mg/ml values, respectively. Vaso-relaxant effect of mn.aq was partially blocked in presence of l-name with ec50, 5.32mg/ml value, but showed concentration dependent significant inhibition of ligand gated and voltage gated ca+2 channels and intracellular ca+2 release, similar to verapamil. Findings of current study designate that aqueous fraction of m. Nigra possesses antihypertensive activity with concentration-dependent vaso-relaxant effect predominantly mediated through endothelial-independent calcium channel blocking pathways accompanied by partial involvement of endothelium-dependent nos mediated relaxation.

Cardiotonic potential of Carissa opaca Stapf ex Haines: A study on isolated rabbit heart.

Carissa opaca (C.O) is a wild shrub, belonging to the family Apocynaceae. The medicinal virtues of this plant have long been known. The present study demonstrates the effects of aqueous-methanolic extract and various fractions (n-butanolic and aqueous) of Carissa opaca on cardiovascular parameters. The perfusion pressure (PP), force of contraction (FC) and heart rate (HR) were assessed on isolated heart of rabbit using Langendroff's technique for crude extract and fractions of C.O, followed by the elucidation of the mechanism of action after estimating toxicity of the plant. Negative ionotropic and positive chronotropic effects, with an increase in PP in isolated perfused rabbit heart were observed the with plant extract and fractions. The aqueous-methanolic extract exhibited maximum response at 1mg/ml while the n-butanolic and aqueous fractions showed a maximum response at 1mg/ml and 10µg/ml respectively. Both fractions produced the same response when treated with atropine (10-5 M), however the actions of adrenaline (10-5 M) and calcium chloride (10-5 M) remained unblocked. Acute toxicity studies indicated that the plant was safe up to 2000 mg/kg and sub-chronic studies demonstrated that no significant change in haematological and biochemical parameters observed. In conclusion, this study supports the folkloric claim of C.O extract.

An assessment of the level of concern among hospital-based health-care workers regarding MERS outbreaks in Saudi Arabia.

BACKGROUND: Middle East Respiratory Syndrome (MERS) is caused by MERS coronavirus (MERS-CoV). More than 80% of reported cases have occurred in Saudi Arabia, with a mortality exceeding 50%. Health-care workers (HCWs) are at risk of acquiring and transmitting this virus, so the concerns of HCWs in Saudi Arabia regarding MERS were evaluated. METHODS: An anonymous, self-administered, previously validated questionnaire was given to 1031 HCWs at three tertiary hospitals in Saudi Arabia from October to December, 2014. Concerns regarding the disease, its severity and governmental efforts to contain it, as well as disease outcomes were assessed using 31 concern statements in five distinct domains. A total concern score was calculated for each HCW. Multiple regression analyses were used to identify predictors of high concern scores. RESULTS: The average age of participants was 37.1 ± 9.0 years, 65.8% were married and 59.1% were nurses. The majority of respondents (70.4%) felt at risk of contracting a MERS-CoV infection at work, 69.1% felt threatened if a colleague contracted MERS-CoV, 60.9% felt obliged to care for patients infected with MERS-CoV and 87.8% did not feel safe at work using standard precautions. In addition, 87.7% believed that the government should isolate patients with MERS in specialized hospitals, 73.7% agreed with travel restriction to and from areas affected by MERS and 65.3% agreed with avoiding inviting expatriates from such areas. After adjustment for covariates, high concern scores were significantly associated with being a Saudi national (p < 0.001), a non-physician (p < 0.001) and working in the central region (p < 0.001). CONCLUSIONS: The majority of respondents reported concern regarding MERS-CoV infection from exposure at work. The overall level of concern may be influenced by previous experience of MERS outbreaks and related cultural issues. The concerns of HCWs may affect their overall effectiveness in an outbreak and should be addressed by incorporating management strategies in outbreak planning.