Spread, circulation, and evolution of the Middle East respiratory syndrome coronavirus

The Middle East respiratory syndrome coronavirus (MERS-CoV) was first documented in the Kingdom of Saudi Arabia (KSA) in 2012 and, to date, has been identified in 180 cases with 43% mortality. In this study, we have determined the MERS-CoV evolutionary rate, documented genetic variants of the virus and their distribution throughout the Arabian peninsula, and identified the genome positions under positive selection, important features for monitoring adaptation of MERS-CoV to human transmission and for identifying the source of infections. Respiratory samples from confirmed KSA MERS cases from May to September 2013 were subjected to whole-genome deep sequencing, and 32 complete or partial sequences (20 were ≥99% complete, 7 were 50 to 94% complete, and 5 were 27 to 50% complete) were obtained, bringing the total available MERS-CoV genomic sequences to 65. An evolutionary rate of 1.12 × 10−3 substitutions per site per year (95% credible interval [95% CI], 8.76 × 10−4; 1.37 × 10−3) was estimated, bringing the time to most recent common ancestor to March 2012 (95% CI, December 2011; June 2012). Only one MERS-CoV codon, spike 1020, located in a domain required for cell entry, is under strong positive selection. Four KSA MERS-CoV phylogenetic clades were found, with 3 clades apparently no longer contributing to current cases. The size of the population infected with MERS-CoV showed a gradual increase to June 2013, followed by a decline, possibly due to increased surveillance and infection control measures combined with a basic reproduction number (R0) for the virus that is less than 1

Transmission and evolution of the Middle East respiratory syndrome coronavirus in Saudi Arabia:a descriptive genomic study

BACKGROUND: Since June, 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) has, worldwide, caused 104 infections in people including 49 deaths, with 82 cases and 41 deaths reported from Saudi Arabia. In addition to confirming diagnosis, we generated the MERS-CoV genomic sequences obtained directly from patient samples to provide important information on MERS-CoV transmission, evolution, and origin. METHODS: Full genome deep sequencing was done on nucleic acid extracted directly from PCR-confirmed clinical samples. Viral genomes were obtained from 21 MERS cases of which 13 had 100%, four 85-95%, and four 30-50% genome coverage. Phylogenetic analysis of the 21 sequences, combined with nine published MERS-CoV genomes, was done. FINDINGS: Three distinct MERS-CoV genotypes were identified in Riyadh. Phylogeographic analyses suggest the MERS-CoV zoonotic reservoir is geographically disperse. Selection analysis of the MERS-CoV genomes reveals the expected accumulation of genetic diversity including changes in the S protein. The genetic diversity in the Al-Hasa cluster suggests that the hospital outbreak might have had more than one virus introduction. INTERPRETATION: We present the largest number of MERS-CoV genomes (21) described so far. MERS-CoV full genome sequences provide greater detail in tracking transmission. Multiple introductions of MERS-CoV are identified and suggest lower R0 values. Transmission within Saudi Arabia is consistent with either movement of an animal reservoir, animal products, or movement of infected people. Further definition of the exposures responsible for the sporadic introductions of MERS-CoV into human populations is urgently needed. FUNDING: Saudi Arabian Ministry of Health, Wellcome Trust, European Community, and National Institute of Health Research University College London Hospitals Biomedical Research Centre

Risk analysis of needle stick and sharp object injuries among health care workers in a tertiary care hospital (Saudi Arabia)

Objective: To study different risk factors associated with needle stick injury among health care workers of a tertiary care hospital in Saudi Arabia. Subjects and methodology: Retrospective study involving all reported cases of needle stick and sharp object injury among health care workers through using Epinet™ access U.K. version 1.3 program in King Saud Medical City (KSMC) during the period (January 2007–December 2011). Results: During the study period, 477 needle stick and sharp object injuries were reported with peak incidence (13.84%) during 2009. Distribution of needle stick and sharp object injuries according to the location of their occurrence clarified that patient room/ward was the most common place of occurrence of NSSIs 150/477, followed by emergency department 82/477, then the intensive and critical care units 70/477. The study presented that nurses were encountered as the most affected job category and use of items is the most common activity associated with the incidents. Most of the incidents were caused by needles with disposable needle and hands were the most affected body parts. Conclusion: Needle stick and sharp object injuries represent a major occupational challenge to health care workers. Prevention should be based on different working lines including immunization, education of health care workers and proper engineering control measures

The Association between Cardiovascular Risk Factors and Carotid Intima-Media Thickness in 42,726 Adults in UK Biobank: A Cross-Sectional Study

Background: Traditional modifiable cardiovascular risk factors, such as high blood pressure, have long been positively correlated with high carotid intima-media thickness (cIMT). However, traditional cardiovascular risk factors made a minor contribution to cIMT variance, meaning that other markers may be regarded as independent markers for increasing cIMT. Aims: To investigate the simple demographic patterns of carotid intima-media thickness (cIMT) in the UK Biobank and to identify which upstream cardiovascular disease (CVD) risk factors are independently associated with cIMT. Methods and Results: A cross-sectional-based study of healthy middle-aged people recruited in the UK between 2006 and 2010 (n = 42,726). Results: This study showed that the cardiovascular risk profile generally worsened across the cIMT quantiles from lowest to highest. The lowest cIMT quartile was defined as having a mean cIMT 748 µm. Specifically, the highest cIMT quantile group had a worse CVD risk factors profile compared to the lowest cIMT quantile group. It was found that, for every one SD increase in age and systolic blood pressure, the mean cIMT increased by 0.357 SD and 0.115 SD, respectively. Conclusion: Systolic blood pressure and age were the strongest independent risk factors for a high cIMT value compared to other risk factors

Molecular Mimics of Classic P-Glycoprotein Inhibitors as Multidrug Resistance Suppressors and Their Synergistic Effect on Paclitaxel

<div><p>P-glycoprotein (Pgp) is a membrane bound efflux pump spread in a variety of tumor cells and considered as a main component of multidrug resistance (MDR) to chemotherapies. In this work, three groups of compounds (imidazolone, oxazolone and vinyl dipeptide derivatives) were synthesized aiming to develop a molecular framework that effectively suppresses MDR. When tested for their influence on Pgp activity, four compounds coded Cur1-01, Cur1-12V, Curox-1 and Curox-3 significantly decreased remaining ATP concentration indicating Pgp substrate site blocking. On the other hand, Cur-3 and Cur-10 significantly increased remaining ATP concentration, which is indicative of Pgp ATPase inhibition. The cytotoxicity of synthesized compounds was examined against Pgp expressing/highly resistant colorectal cancer cell lines (LS-174T). Compounds Cur-1 and Cur-3 showed considerable cytotoxicity with IC₅₀ values of 7.6 and 8.9 μM, respectively. Equitoxic combination (at IC₅₀ concentrations) of PTX and Cur-3 greatly diminished resistant cell clone from 45.7% to 2.5%, albeit with some drop in potency from IC₅₀ of 7.9 nM to IC₅₀ of 23.8 nM. On the other hand, combination of PTX and the non-cytotoxic Cur1-12V (10 μM) significantly decreased the IC₅₀ of PTX to 3.8 nM as well as the resistant fraction to 16.2%. The combination test was confirmed using the same protocol but on another resistant CRC cell line (HCT-116) as we obtained similar results. Both Cur-3 and Cur1-12V (10 μM) significantly increased the cellular entrapment of Pgp probe (doxorubicin) elevating its intracellular concentration from 1.9 pmole/cell to 3.0 and 2.9 pmole/cell, respectively.</p></div

Chemomedulatory effects of test compounds on the cytotoxicity parameters of PTX against LS-174T cell line.

<p>Chemomedulatory effects of test compounds on the cytotoxicity parameters of PTX against LS-174T cell line.</p

The effect of serial equitoxic concentrations (ratio 1:100) of Cur3 (A), and 10 μM (B), and serial concentration of Cur1-12V (ratio 1:100) (C) on the cytotoxicity of PTX in HCT-116 cells.

<p>Cells were exposed to serial dilution of PTX (●), Chemosensetizer (▼) or their combination (○) for 72 h. Cell viability was determined using SRB assay.</p

Examples of Pgp inhibitors.

<p>Examples of Pgp inhibitors.</p

Structure and codes of the synthesized oxazolones and imidazolones.

<p>Structure and codes of the synthesized oxazolones and imidazolones.</p

Cytotoxic Activity of synthesized compounds against LS174T CRC cell lines.

<p>Cytotoxic Activity of synthesized compounds against LS174T CRC cell lines.</p