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BackgroundStreptococcus pneumoniae is still one of the major causes of morbidity and mortality worldwide. The prevalent serotype distribution had shown variation along different studies conducted at different time intervals. In order to efficiently assess the epidemiology of the diseases for effective preventive and treatment strategies, serotype prevalence need to be periodically reassessed.ObjectivesConducting a reassessment of the prevalent S. pneumoniae serotypes in Egypt as an essential step in the search for a regional vaccine. In addition, monitoring the antibiotic susceptibility patterns of pneumococcal strains currently causing infections as an evaluation of therapeutic strategies applied.Materials and MethodsA total of 100 specimens of different sources were collected in Cairo, Egypt, from 2011 to 2013, representing almost all different types of diseases caused by S. pneumoniae such as meningitis, pneumonia, otitis media and sinusitis. Conventional and molecular identification methods were performed, the antimicrobial susceptibility patterns were assessed and serotyping was done using PCR assays to identify the most prevalent types. In addition, detection of certain virulence genes for the most prevalent serotypes was carried out.ResultsOur results revealed that in Egypt, currently, the most prevalent serotypes were serogroup 6 and serotype 19F as they represented 58% of all isolates. High rates of resistance were found to different antibiotic classes. The lytA and psaA genes were found to be more sensitive for S. pneumoniae identification than ply.ConclusionsOur study illustrates the importance of constantly monitoring the prevalent serotypes in any region in order to aid in the development of more effective vaccines.

The use of Synthetic antioxidants is being widely restricted because of their reported toxic and carcinogenic effects. Thus, now there is considerable interest being focused towards finding antioxidants from natural sources with any unlikely effects. There is also considerable evidence which indicates lower risk of Cancer in yeast extracts and the used commercial media. The present study was conducted to determine antioxidant activity of yeast extracts grown on four different commercial media using DPPH, total phenolic content, total antioxidant activity and TBARS and to study the anticancer activity of yeast extracts on the mentioned media against human hepato carcinoma cell line (HEPG-2) using the MTT assay, Cell Cycle Analysis and mRNA Expression of Cell Apoptosis-related Gene. The yeast extract of corn meal was found to have more antioxidant activity than other commercial media. The antioxidant potential was then correlated with the total phenol content. The yeast extract of corn meal showed maximum anticancer activity against HEPG-2 as compared to that of other used media. Overall, the results achieved in this study are promising and indicate that yeast fermentation on corn meal medium is better than other used media to get on antioxidant and anticancer activities.

Streptococcus pneumoniae is a pathogen that causes serious invasive infections, such as septicemia, meningitis and pneumonia in addition to mild upper respiratory tract infections. Protection from pneumococcal diseases is thought to be mediated mainly by serotype-specific antibodies to capsular antigens. Pneumococcal conjugate vaccine consists of sugars (polysaccharides) from the capsule of the bacterium S. pneumoniae that are conjugated to a carrier protein. Three pneumococcal conjugated vaccines, each directed against a group of serotypes, are registered in Egypt; however, local vaccine production is required to cover the most prevalent serotypes. In this work, capsular polysaccharide from the most current and prevalent serotypes in Egypt were extracted, purified and conjugated to bovine serum albumin (BSA). The polysaccharide protein conjugate was purified through ultrafiltration technique and molecular size distribution was compared to an available vaccine. The immunogenicity of the prepared vaccine was examined via two methods: First, by measuring the levels of the elicited antibodies in the sera of the vaccinated mice; second, by challenging the vaccinated groups of mice with approximately 107 CFU of each specific serotype and determining the degree of protection the developled vaccine offers. Our results show that the developed conjugated capsular polysaccharide vaccine is highly immunogenic and protective in mice. This finding illustrates the importance of tracking the most recent and predominant peneumococcal serotypes to generate effective vaccines, instead of using expensive imported vaccines with large number of serotypes which might not be even present in the community.