Prevalence of methicillin-resistant Staphylococcus aureus in Saudi Arabia: Systemic review and meta-analysis

In recent years, methicillin-resistant Staphylococcucs aureus (MRSA) have become a truly global challenge. Systemic review and meta-analysis was performed to summarize the prevalence of MRSA in different regions of Kingdom of Saudi Arabia (KSA). A search of the PubMed, Google and Google Scholar databases for studies published during the period of 1 January 2002 through 31 December 2012 was conducted. We included studies that looked at the number and prevalence of MRSA among total S. aureus. Meta-analyst and comprehensive meta-analysis were used for statistical analysis. Twenty six studies were included in the review, representing five regions of KSA. Pooled estimation of 22,793 S. aureus strains showed 35.6% (95% Confidence interval (CI), 0.28 –0.42; P < 0.01) of the strains were MRSA with significant heterogeneity. Prevalence of MRSA ranged from 5.97% to 94% in Dahran and Riyadh cities, respectively. MRSA proportion among KSA regions is slightly high and varied from one city to the other.Key words: Saudi – methicillin-resistant Staphylococcucs aureus -systemic review

Polymorphism in the protein of the thoracic muscle of an endemic bee (Anthophora pauperata) in the St Katherine Protectorate

Genetic variability of the solitary bee Anthophora pauperata, endemic to the St Katherine Protectorate, was assessed within and between seven wadis in South Sinai, Egypt. Low levels of variation were found, with most diversity within rather than between sites. There were a total of 34 bands, of which only seven were polymorphic among individuals

Purification and characterization of phenoloxidase from immunized haemolymph of Schistocerca gregaria

Phenoloxidase (PO) is a key factor in insect immunity. On invasion of microorganisms and pathogens, prophenoloxidase (PPO) changes to its active form, PO. The present study has been conducted to purify and characterize the PO from the haemolymph of desert locust, Schistocerca gregaria (Forskal) following activation of immune system by invasion of bacteria, Bacillus thuringiensis kurstaki (Bt). PO is purified by a combination of ammonium sulfate precipitation, blue sepharose CL-6B and phenyl sepharose CL-4B chromatography yielded a 209.97-fold purity and 54.75% recovery of activity. Sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) reveals that the molecular weight of the purified PO is 70.154 kDa. The purified PO is characterized in terms of its biochemical and enzymatic properties by using L-DOPA as a specific substrate. Ca2+ and Cu2+ significantly stimulated PO activity when compared with other metals. The PO reaction was strongly inhibited by phenylthiourea and thiourea, moderately inhibited by ethylene diamine tetractic acid (EDTA) and poorly inhibited by ethylene glycol tetraacetic acid (EGTA) and diethyl dithiocarbamate (DTC). Inhibition of PO showed excellent recovery ability by addition of Ca2+ on EGTA-inhibited enzyme. Therefore, PO is most probably a kind of tyrosinase-type Ca2+-containing metalloenzyme. The content of Ca2+ is higher than other trace metal elements. The reactive intermediates yielded by PO with its specific substrate L-DOPA had a broad-spectrum bactericidal activity against Gram +ve bacteria (Bacillus cereus and Staphylococcus aureus) with a greater degree more than Gram-ve bacteria (Escherichia coli and Pseudomonas aeruginosa). From the present study, PO from S. gregaria is most probably a tyrosinasetype calcium-containing mono-phenoloxidase, which functions not only as a catalytic enzyme in melanin production in locusts, but perhaps also as a humoral factor in host defense via melaninization as in other insects.Key words: Schistocerca gregaria, phenoloxidase, purification

PREPARATION AND EVALUATION OF CHEMICALLY INACTIVATED SALMONELLA ENTERITIDIS VACCINE IN CHICKENS

  Objective: Salmonella enteritidis ghosts (SEGs) is a non-living empty bacterial cell envelopes which were generated using a different concentration of sodium hydroxide (NaOH) 6.4 mg/mL and evaluated as a vaccine candidate in specific pathogen-free (SPF) chicken. SEGs have been produced by chemical-mediated lysis and evaluated the potential efficacy of chemically induced SEG vaccine and its ability to induce protective immune responses against virulent S. enteritidis challenge in SPF chickens.Methods: SPF chickens were divided into three groups: Group A (non-vaccinated control), Group B (vaccinated with prepared vaccine), and Group C (vaccinated with commercial vaccine).Results: Vaccination of SPF chicken with SEGs induced higher immune responses before and after virulent challenge. SPF chicken vaccinated with SEGs showed increasing in serum enzyme-linked immunosorbent assay (ELISA) antibodies. During the vaccination period, Groups B and C showed higher serum antibody titer compared to Group A. The minimal inhibitory concentration (MIC) of NaOH was capable of inducing non-living SEGs, and it has successfully generated non-living SEGs by MIC of NaOH.Conclusion: It is a one-step process which means easy manufacturing and low production cost compared to protein E-mediated lysis method. Chemically induced SEG vaccine is a highly effective method for inducing protective immunity. This study strongly suggests that SEGs will be a permissive vaccine, as the method of inhibition of S. enteritidis was safe and cheaper than other methods, and it gave a good protection

Effects of Internal Gas Explosion on an Underwater Tunnel Roof

An underwater reinforced concrete tunnel roof is subjected to an internal gas explosion. Dynamic analyses are performed for three cases, namely, (1) an uncoupled solution, (2) class II coupling analysis and (3) full model with class I and II couplings. Three load cases are considered, dead (gravity) load, uniformly distributed vertical loads from sand and water and finally an internal pressure gas explosion. Linear and non-linear constitutive relationships are considered for the materials constituting the gas explosion problem. Results include time deflection of tunnel roof, time histories of stresses in vertical reinforcing bars and contours of concrete stresses for tunnel roof. By conducting analyses from various models, the question whether the tunnel would be damaged to such an extent that its serviceability would be impaired is investigated

Dynamics on expanding spaces: modeling the emergence of novelties

Novelties are part of our daily lives. We constantly adopt new technologies, conceive new ideas, meet new people, experiment with new situations. Occasionally, we as individuals, in a complicated cognitive and sometimes fortuitous process, come up with something that is not only new to us, but to our entire society so that what is a personal novelty can turn into an innovation at a global level. Innovations occur throughout social, biological and technological systems and, though we perceive them as a very natural ingredient of our human experience, little is known about the processes determining their emergence. Still the statistical occurrence of innovations shows striking regularities that represent a starting point to get a deeper insight in the whole phenomenology. This paper represents a small step in that direction, focusing on reviewing the scientific attempts to effectively model the emergence of the new and its regularities, with an emphasis on more recent contributions: from the plain Simon's model tracing back to the 1950s, to the newest model of Polya's urn with triggering of one novelty by another. What seems to be key in the successful modelling schemes proposed so far is the idea of looking at evolution as a path in a complex space, physical, conceptual, biological, technological, whose structure and topology get continuously reshaped and expanded by the occurrence of the new. Mathematically it is very interesting to look at the consequences of the interplay between the "actual" and the "possible" and this is the aim of this short review.Comment: 25 pages, 10 figure

Selective Hydrogenation of Cinnamaldehyde over Salt-Promoted Pd-Based Catalysts

Abstract The effect of salt additives (AlCl 3 , SnCl 2 , FeCl 3 ) on the catalytic behavior o

Handwriting-Based Gender Classification Using End-to-End Deep Neural Networks

Handwriting-based gender classification is a well-researched problem that has been approached mainly by traditional machine learning techniques. In this paper, we propose a novel deep learning-based approach for this task. Specifically, we present a convolutional neural network (CNN), which performs automatic feature extraction from a given handwritten image, followed by classification of the writer's gender. Also, we introduce a new dataset of labeled handwritten samples, in Hebrew and English, of 405 participants. Comparing the gender classification accuracy on this dataset against human examiners, our results show that the proposed deep learning-based approach is substantially more accurate than that of humans

Hyperhomocysteinemia and Low Folate and Vitamin B12 Are Associated with Vascular Dysfunction and Impaired Nitric Oxide Sensitivity in Morbidly Obese Patients.

There is a high prevalence of hyperhomocysteinemia that has been linked to high cardiovascular risk in obese individuals and could be attributed to poor nutritional status of folate and vitamin B12. We sought to examine the association between blood homocysteine (Hcy) folate, and vitamin B12 levels and vascular dysfunction in morbidly obese adults using novel ex vivo flow-induced dilation (FID) measurements of isolated adipose tissue arterioles. Brachial artery flow-mediated dilation (FMD) was also measured. Subcutaneous and visceral adipose tissue biopsies were obtained from morbidly obese individuals and non-obese controls. Resistance arterioles were isolated in which FID, acetylcholine-induced dilation (AChID), and nitric oxide (NO) production were measured in the absence or presence of the NO synthase inhibitor, L-NAME, Hcy, or the superoxide dismutase mimetic, TEMPOL. Our results demonstrated that plasma Hcy concentrations were significantly higher, while folate, vitamin B12, and NO were significantly lower in obese subjects compared to controls. Hcy concentrations correlated positively with BMI, fat %, and insulin levels but not with folate or vitamin B12. Brachial and arteriolar vasodilation were lower in obese subjects, positively correlated with folate and vitamin B12, and inversely correlated with Hcy. Arteriolar NO measurements and sensitivity to L-NAME were lower in obese subjects compared to controls. Finally, Hcy incubation reduced arteriolar FID and NO sensitivity, an effect that was abolished by TEMPOL. In conclusion, these data suggest that high concentrations of plasma Hcy and low concentrations of folate and vitamin B12 could be independent predictors of vascular dysfunction in morbidly obese individuals

The clinical significance of tumor infiltrating lymphoctyes in breast cancer: does subtype matter?

Tumor infiltrating lymphocytes (TILs) are commonly detected in breast tumors but their bearing on disease outcome is uncertain. The importance of TILs appears to be subtype-specific and varies depending on the histologic characteristics of the tumor. As our understanding of tumorigenesis is increasing the relevance of immunobiology will become apparent