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Objective(s): Pneumococcal cell wall (PCW) is an inflammatory component in Streptococcus pneumoniae. The cell surface proteins and the toll-like receptors (TLR) signaling response were investigated in the human lung epithelial (A549) cells inoculated with PCW of different serotypes. Materials and Methods: The presence of genes encoding these proteins was determined using polymerase chain reaction (PCR). The structure of the cell walls was analyzed by proton nuclear magnetic resonance (1H NMR). The A549 cell line was challenged with PCW extracts of different serotypes. RNA from the infected host cells was extracted and tested against a total of 84 genes associated with TLR signaling pathways (TLR 1-6 and 10) using RT2 Profiler PCR Array. Results: Cell surface proteins; ply, lytA, nanA, nanB, and cbpD genes were present in all serotypes. The distribution and structure of surface protein genes suggest behavioral changes in the molecules, contributing to the resilience of the strains to antibiotic treatment. Conclusion: TLR2 showed the highest expression, while serotypes 1, 3, and 5 induced higher TNFα and IL-1α, suggesting to be more immunogenic than the other strains tested. [ABSTRACT FROM AUTHOR]

Objective: To characterise a collection of pili-carrying and none pili-carrying pneumococcal isolates of clinical origin for serotypes, antibiotic resistance and genotype. Methods: In total, 42 clinical isolates were collected between October 2017 and December 2019. Those isolates were analysed for antimicrobial susceptibility, serotype distribution, detection of pneumococcal virulence and pilus genes. Multilocus sequence typing was performed only for piliated isolates, followed by phylogenetic analysis. Results: The common isolation sites among the pneumococcal isolates were tracheal aspirate (28.6%), blood (26.2%), and sputum (23.8%). Fifty percent isolates were resistant to erythromycin, tetracycline (50.0%) and trimethoprim-sulfamethoxazole (43.0%). The most frequent were serotypes 19F (28.6%), 6A/B (23.8%) and 19A (14.3%). Piliated isolates were detected in a small proportion (33.3%); 64.3% were multidrug-resistant. ST320 was the prevalent sequence type among the piliated isolates and genetically related to the Pneumococcal Molecular Epidemiology Network clones Taiwan19F-14 (CC271). In the phylogenetic analysis, some piliated isolates showed a close association having similar ST320, carrying serotype 19A and both pilus genes indicating their clonal spread. Conclusions: Pneumococcal lineages of piliated isolates have been globally disseminated and pili could have played a role in the spread of antibiotic resistant clones. [ABSTRACT FROM AUTHOR]

Nanomedicine is now being introduced as a recent trend in the field of medicine. It has been documented that metal nanoparticles have antimicrobial effects for bacteria, fungi and viruses. Recent advances in technology has revived the use of silver nanoparticles in the medical field; treatment, diagnosis, monitoring and control of disease. It has been used since ancient times for treating wide range of illnesses. Bacterial cells adheres to surfaces and develop structures known as biofilms. These structures are natural survival strategy of the bacteria to invade the host. They are more tolerant to commonly used antimicrobial agents, thus being more difficult to be controlled. This leads to increase in severity of infection. In this study, we have investigated the effect of silver nanoparticles in the formation of biofilm in multidrug resistant strains of Pseudomonas aeruginosa. Observation showed that biofilm formation occurred at bacterial concentration of 106 cfu/ml for the sensitive strain of P. aeruginosa while in the resistant strain, the biofilm was evident at bacterial concentration of about 103 cfu/ml. The biofilm were then tested against various concentrations of silver nanoparticles to determine the inhibitory effect of the silver nanoparticles. In the sensitive strain, 20 μg/ml of silver nanoparticles inhibited the growth optimally at bacterial concentration of 104 cfu/ml with an inhibition rate of 67%. Similarly, silver nanoparticles inhibited the formation of biofilm in the resistant strain at an optimal bacterial concentration of 105 cfu/ml with an inhibition rate of 56%. Thus, silver nanoparticles could be used as a potential alternative therapy to reduce severity of disease due to P. aeruginosa infections. [ABSTRACT FROM AUTHOR]

Background: Streptococcus pneumoniae is a major causative agent of severe infections, including sepsis, pneumonia, meningitis, and otitis media, that has since become a major public health concern. In this study, the serotypes distribution of pneumococcal isolates was investigated to predict the efficacy of the 7-valent pneumococcal conjugate vaccine (PCV7) among the Malaysian populations. Methodology/Principal Findings: A total of 151 clinical isolates were serotyped using multiplex PCR assays. Out of them, there were 21.2% penicillin-resistant, 29.1% penicillin-intermediate, and 49.7% penicillin-susceptible S.pneumoniae strains. Serotypes detected among the Malaysian isolates were 1, 3, 10A, 11A/11D, 12F/12A, 14, 15A, 15B/15C, 16F, 18C/18B/18A/ 18F, 19A, 19F, 23F, 35B, 35F/47F, 6A/6B, 7C/7B/40, 7F/7A, 9V/9A, and 34. Serotype 19F and 23F were the two most prevalent serotypes detected. Serotypes are highly associated with invasiveness of isolates (p=0.001) and penicillin susceptibility (p<0.001). Serotype 19F was observed to have increased resistance against penicillin while serotype 19A has high invasive tendency. Age of patients was an important factor underlying the pneumococcal serotypes (p=0.03) and clinical sites of infections (p<0.001). High prevalence of pneumococcal isolates were detected among children <5 years old at nasopharyngeal sites while elderly adults Ζ60 years old were at increased risk for pneumococcal bacteremia. Conclusion/Significance: Current study revealed that a number of serotypes, especially those associated with high penicillin resistance, have been formulated in the PCV7. Therefore, the protections expected from the routine use of PCV7 would be encouraging for the Malaysian. However, it is not possible to predict serotypes that might become predominant in the future and hence continued surveillance of circulating serotypes will be needed. [ABSTRACT FROM AUTHOR]

Introduction: Rapid detection of influenza viruses and respiratory syncytial virus (RSV) can be achieved by having rapid molecular point of care tests (POCTs). This expedites the diagnosis attributed by having similar clinical presentations leading to facilitation of precision medicine and reduction of antimicrobial resistance. The growing number of POCTs foster the need to ensure that these POCTs have satisfactory and reliable performance. With that the aim of this study is to evaluate the performance of rapid molecular POCT regarded as 'X' for the detection of Influenza viruses and RSV in comparison to multiplex PCR. Methods: A laboratory-based study was conducted from January to December 2020 which involved analysis of 116 nasopharyngeal swabs, tested using POCT X and multiplex PCR as a method of reference. The performance analysis incorporated the sensitivity, specificity, positive and negative predicted values determination. The cycle threshold values were reviewed for discordant results. Results: The POCT X demonstrated sensitivity of 88.57% with 100% specificity for Influenza A virus, and 85.71% of sensitivity with 100% specificity for influenza B virus detection. Meanwhile it revealed 100% sensitivity and specificity for RSV detection. There were ten specimens demonstrating discordant results whereby viruses were not detected by POCT X, however detected by multiplex PCR. The POCT X was not able to detect eight (12.9%) and two (16.7%) influenza A and B viruses respectively. Conclusion: The overall performance of POCT X was corresponded to multiplex PCR. This best served as a steadfast ancillary test for influenza and RSV infection. [ABSTRACT FROM AUTHOR]

Objectives: Pneumococcal cell wall (PCW) is an inflammatory component in Streptococcus pneumoniae . The cell surface proteins and the toll-like receptors (TLR) signaling response were investigated in the human lung epithelial (A549) cells inoculated with PCW of different serotypes., Materials and Methods: The presence of genes encoding these proteins was determined using polymerase chain reaction (PCR). The structure of the cell walls was analyzed by proton nuclear magnetic resonance (1H NMR). The A549 cell line was challenged with PCW extracts of different serotypes. RNA from the infected host cells was extracted and tested against a total of 84 genes associated with TLR signaling pathways (TLR 1-6 and 10) using RT2 Profiler PCR Array., Results: Cell surface proteins; ply , lytA , nanA , nanB , and cbpD genes were present in all serotypes. The distribution and structure of surface protein genes suggest behavioral changes in the molecules, contributing to the resilience of the strains to antibiotic treatment., Conclusion: TLR2 showed the highest expression, while serotypes 1, 3, and 5 induced higher TNFα and IL-1α, suggesting to be more immunogenic than the other strains tested., Competing Interests: No potential conflicts of interest were reported by the author(s).