Serological and molecular capsular typing, antibiotic susceptibility of Streptococcus pneumoniae isolates from invasive and non-invasive infections

Krishnappa, Lakshmana Gowda; Marie, Mohammed Ali M.; John, James; Dabwan, Khaled Homoud M; Shashidhar, Pradeep Chikkabidare

doi:10.1556/amicr.61.2014.2.7

Cited by 11 publications

(6 citation statements)

References 19 publications

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“…A high multidrug resistance rate was also documented, while vancomycin tolerance was not observed [100]. It is important to note that cotrimoxazole resistance in Saudi Arabia is the highest within the region, reaching up to 100 % in patients of all ages with invasive and non-invasive diseases [101,102]. This represents a disturbing increase from the resistance rates observed in the early 2000s from paediatric patients [103].…”

Section: Epidemiology Of Resistance In the Middle East Regionmentioning

confidence: 99%

“…In a recent retrospective study [104], S. pneumoniae was the fourth most common keratitis-causing bacteria. In contrast to previous studies, where pneumococcal strains were isolated from sterile body sites such as cerebrospinal fluid, blood and synovial fluid [99][100][101][102], this study only included corneal isolates, and of these the pneumococcal strains expressed lower resistance rates to penicillin and erythromycin, although no resistance to FQ or vancomycin was observed.…”

Section: Epidemiology Of Resistance In the Middle East Regionmentioning

confidence: 99%

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Molecular mechanisms and epidemiology of resistance in Streptococcus pneumoniae in the Middle East region

Moujaber

Osman

Rafei

et al. 2017

Journal of Medical Microbiology

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Purpose. Streptococcus pneumoniae is a commensal bacterium that normally colonizes the human nasopharyngeal cavity. Once disseminated, it can cause several diseases, ranging from non-invasive infections such as acute otitis media and sinusitis through to invasive infections with higher mortality, including meningitis and septicaemia. Since the identification of the first S. pneumoniae strain with decreased susceptibility to penicillin in the 1960s, antibiotic resistance among S. pneumoniae has increased disturbingly and the mechanisms of resistance have begun to unfold.Methodology. This work briefly reviewed the available data on the molecular mechanisms underlying antimicrobial resistance and its epidemiology among pneumococcal strains in Middle Eastern countries.Key findings. Both intrinsic and acquired mechanisms (mutations, acquisition of novel mobile genetic elements and sometimes gene duplication and overexpression) affect susceptibility to a large variety of antibiotics. In Middle Eastern countries, including Lebanon, Iran, Saudi Arabia and Turkey, surveillance showed a disturbing increase in the strength and prevalence of resistance to antibiotics over the years, especially in the last decade. However, no surveillance reports were found in other Middle Eastern countries, such as Syria and Iraq.Conclusion. In order to better survey, control and prevent the emergence of multidrug-and extremely drug-resistant S. pneumoniae strains, antimicrobial stewardship, national surveillance and public awareness programmes should be developed urgently in Middle Eastern countries.

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Section: Epidemiology Of Resistance In the Middle East Regionmentioning

confidence: 99%

Section: Epidemiology Of Resistance In the Middle East Regionmentioning

confidence: 99%

Molecular mechanisms and epidemiology of resistance in Streptococcus pneumoniae in the Middle East region

Moujaber

Osman

Rafei

et al. 2017

Journal of Medical Microbiology

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“…Successful pathogens like S . pneumoniae have evolved new strategies to counter existing vaccine and antibiotics [ 41 ]. Although multivalent vaccines against S .…”

Section: Discussionmentioning

confidence: 99%

Pneumococal Surface Protein A (PspA) Regulates Programmed Death Ligand 1 Expression on Dendritic Cells in a Toll-Like Receptor 2 and Calcium Dependent Manner

et al. 2015

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Pneumonia leads to high mortality in children under the age of five years worldwide, resulting in close to 20 percent of all deaths in this age group. Therefore, investigations into host-pathogen interactions during Streptococcus pneumoniae infection are key in devising strategies towards the development of better vaccines and drugs. To that end, in this study we investigated the role of S. pneumoniae and its surface antigen Pneumococcal surface protein A (PspA) in modulating the expression of co-stimulatory molecule Programmed Death Ligand 1 (PD-L1) expression on dendritic cells (DCs) and the subsequent effects of increased PD-L1 on key defence responses. Our data indicate that stimulation of DCs with PspA increases the surface expression of PD-L1 in a time and dose dependent manner. Characterization of mechanisms involved in PspA induced expression of PD-L1 indicate the involvement of Toll-Like Receptor 2 (TLR2) and calcium homeostasis. While calcium release from intracellular stores positively regulated PD-L1 expression, calcium influx from external milieu negatively regulated PD-L1 expression. Increase in PD-L1 expression, when costimulated with PspA and through TLR2 was higher than when stimulated with PspA or through TLR2. Further, knockdown of TLR2 and the intermediates in the TLR signaling machinery pointed towards the involvement of a MyD88 dependent pathway in PspA induced PD-L1 expression. Incubation of DCs with S. pneumoniae resulted in the up-regulation of PD-L1 expression, while infection with a strain lacking surface PspA failed to do so. Our data also suggests the role of PspA in ROS generation. These results suggest a novel and specific role for PspA in modulating immune responses against S. pneumoniae by regulating PD-L1 expression.

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“…after 24 h of bacterial inoculation, rats of each test group were administered with oleuropein NLC dispersion (100 mg/kg, qd, intraperitoneal injection) for 7 days. [43,44]…”

Section: In Vivo Methods For Inducing Bacterial Meningitismentioning

confidence: 99%

“…Six slices were used from each specimen and 10 random images from each slice were used for observation. [2,44]…”

Section: Histological Examinationmentioning

confidence: 99%

Untitled

Reddy¹

2019

AJP

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Background: Olive leaf, a versatile plant obtained from Olea europaea which was enriched with various secondary metabolites likes polyphenols, secoirodiods eg. Oleuropein, Hydroxytyrosol etc. Current treatment modalities for meningitis were ended up with MDR. Hence, a new strategy is mandate to alleviate bacterial meningitis. Objective: Current research structured to identify the potential of Oleuropein loaded NLC in the inhibition of Bacterial Meningitis. Glycerol is used as bio-solvent in hot blanching assisted microwave extraction & extracts were analyzed by using UV, FTIR, HPTLC and HPLC to quantify the Oleuropein. Methodology: NLC was formulated by melt dispersion ultrasonication method using Box-behnken design. Formulated NLC was analyzed for particle size, zeta potential and in-vitro drug release studies. Toxicity and Histo-pathological examination was done in albino Wistar rats using cerebellar cistern puncture method to estimate In-vivo potential of Oleuropein in bacterial meningitis. Results and Discussion: From the data, it was observed that hot blanching process potentiates the extraction and the data depicts that aqueous glycerol extract contain huge amount of Oleuropein. Optimized NLC resides with 165nm of size, ZP of -40mv and PDI of 0.3 with a sustainable release of drug for 12hrs. By Histo-pathological examination, regeneration of brain tissue was initiated in the hippocampus region in treated group as compared to control group. Conclusion: Combination of hot blanching with microwave extraction for Oleuropein and subsequent loading of drug into NLC shown significant positive effect on treatment of Streptococcal meningitis.

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Serological and molecular capsular typing, antibiotic susceptibility of Streptococcus pneumoniae isolates from invasive and non-invasive infections

Cited by 11 publications

References 19 publications

Molecular mechanisms and epidemiology of resistance in Streptococcus pneumoniae in the Middle East region

Molecular mechanisms and epidemiology of resistance in Streptococcus pneumoniae in the Middle East region

Pneumococal Surface Protein A (PspA) Regulates Programmed Death Ligand 1 Expression on Dendritic Cells in a Toll-Like Receptor 2 and Calcium Dependent Manner

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