keyword
MENU ▼
Read by QxMD icon Read
search

Pneumococci

keyword
https://www.readbyqxmd.com/read/28736074/a-novel-genetic-variant-of-streptococcus-pneumoniae-serotype-11a-discovered-in-fiji
#1
Sam Manna, Belinda Ortika, Eileen M Dunne, Kathryn E Holt, Mike Kama, Fiona M Russell, Jason Hinds, Catherine Satzke
OBJECTIVES: As part of annual cross-sectional Streptococcus pneumoniae carriage surveys in Fiji (2012-2015), we detected pneumococci in over 100 nasopharyngeal swabs that serotyped as '11F-like' by microarray. We examined the genetic basis of this divergence in the 11F-like capsular polysaccharide (cps) locus, compared to the reference 11F cps sequence. The impact of this diversity on capsule phenotype, as well as serotyping results using genetic and serological methods, was determined...
July 20, 2017: Clinical Microbiology and Infection
https://www.readbyqxmd.com/read/28711510/serotyping-of-brunei-pneumococcal-clinical-strains-and-the-investigation-of-their-capability-to-adhere-and-invade-a-brain-endothelium-model
#2
Nurul Adhwa Rahman, Aishah Sharudin, Suwarni Diah, Siti Hanna Muharram
INTRODUCTION: Pneumococcal infections have caused morbidity and mortality globally. Streptococcus pneumoniae (pneumococci) are commensal bacteria that colonize the nasopharynx, asymptomatically. From there, pneumococci can spread in the lungs causing pneumonia and disseminate in the bloodstream causing bacteremia (sepsis) and reach the brain leading to meningitis. Endothelial cells are one of the most important components of the blood-brain barrier that separates the blood from the brain and plays the first protective role against pneumococcal entry...
July 12, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28711389/population-genetic-structure-antibiotic-resistance-capsule-switching-and-evolution-of-invasive-pneumococci-before-conjugate-vaccination-in-malawi
#3
Chrispin Chaguza, Jennifer E Cornick, Cheryl P Andam, Rebecca A Gladstone, Maaike Alaerts, Patrick Musicha, Chikondi Peno, Naor Bar-Zeev, Arox W Kamng'ona, Anmol M Kiran, Chisomo L Msefula, Lesley McGee, Robert F Breiman, Aras Kadioglu, Neil French, Robert S Heyderman, William P Hanage, Stephen D Bentley, Dean B Everett
INTRODUCTION: Pneumococcal infections cause a high death toll in Sub Saharan Africa (SSA) but the recently rolled out pneumococcal conjugate vaccines (PCV) will reduce the disease burden. To better understand the population impact of these vaccines, comprehensive analysis of large collections of pneumococcal isolates sampled prior to vaccination is required. Here we present a population genomic study of the invasive pneumococcal isolates sampled before the implementation of PCV13 in Malawi...
July 12, 2017: Vaccine
https://www.readbyqxmd.com/read/28702310/development-of-pcrseqtyping-a-novel-molecular-assay-for-typing-of-streptococcus-pneumoniae
#4
Geetha Nagaraj, Feroze Ganaie, Vandana Govindan, Kadahalli Lingegowda Ravikumar
BACKGROUND: Precise serotyping of pneumococci is essential for vaccine development, to better understand the pathogenicity and trends of drug resistance. Currently used conventional and molecular methods of serotyping are expensive and time-consuming, with limited coverage of serotypes. An accurate and rapid serotyping method with complete coverage of serotypes is an urgent necessity. This study describes the development and application of a novel technology that addresses this need. METHODS: Polymerase chain reaction (PCR) was performed, targeting 1061 bp cpsB region, and the amplicon was subjected to sequencing...
2017: Pneumonia
https://www.readbyqxmd.com/read/28690025/invasive-pneumococcal-disease-caused-by-ceftriaxone-resistant-streptococcus-pneumoniae-in-taiwan
#5
Hao-Yuan Lee, Tsu-Lan Wu, Lin-Hui Su, Hsin-Chieh Li, Rajendra Prasad Janapatla, Chyi-Liang Chen, Cheng-Hsun Chiu
BACKGROUND: Invasive pneumococcal disease (IPD) was associated with mortality, but the risk factors associated with mortality remains controversial. METHODS: A retrospective cohort study was designed. All patients with IPD from 2011 to 2013 admitted in a medical center were screened and collected for their clinical presentations and laboratory characteristics. RESULTS: Approximately half of the 134 IPD isolates derived from these patients belonged to three major serotypes (19A, 6A and 3), which are included in 13-valent pneumococcal conjugate vaccine (PCV13), but not in 7-valent pneumococcal conjugate vaccine (PCV7)...
June 26, 2017: Journal of Microbiology, Immunology, and Infection, Wei Mian Yu Gan Ran za Zhi
https://www.readbyqxmd.com/read/28659923/subcutaneous-immunization-with-fusion-protein-dnaj-%C3%AE-a146ply-without-additional-adjuvants-induces-both-humoral-and-cellular-immunity-against-pneumococcal-infection-partially-depending-on-tlr4
#6
Yufeng Su, Dagen Li, Yan Xing, Hong Wang, Jian Wang, Jun Yuan, Xiaofang Wang, Fang Cui, Yibing Yin, Xuemei Zhang
Subunit vaccines that are poorly immunogenic are often combined with adjuvants for immunization. Our previous research identified a pneumolysin variant (ΔA146Ply), a Toll-like receptor 4 agonist, that was an effective adjuvant in the protection of fusion protein DnaJ-ΔA146Ply against mucosal Streptococcus pneumoniae infections. For pneumococcal vaccines, World Health Organization recommend injection as a regular vaccination approach. Subcutaneous immunization is a common and effective method of injection, so we explored the immunity mechanism of subcutaneous immunization with DnaJ-ΔA146Ply...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28657670/mapping-the-recognition-domains-of-pneumococcal-fibronectin-binding-proteins-pava-and-pavb-demonstrates-a-common-pattern-of-molecular-interactions-with-fibronectin-type-iii-repeats
#7
Sajida Kanwal, Inga Jensch, Gottfried J Palm, Mark Brönstrup, Manfred Rohde, Thomas P Kohler, Daniela Somplatzki, Werner Tegge, Howard F Jenkinson, Sven Hammerschmidt
Colonization of mucosal respiratory surfaces is a prerequisite for the human pathobiont Streptococcus pneumoniae (the pneumococcus) to cause severe invasive infections. The arsenal of pneumococcal adhesins interacts with a multitude of extracellular matrix proteins. A paradigm for pneumococci is their interaction with the adhesive glycoprotein fibronectin, which facilitates bacterial adherence to host cells. Here, we deciphered the molecular interaction between fibronectin and pneumococcal fibronectin-binding proteins (FnBPs) PavA and PavB, respectively...
June 28, 2017: Molecular Microbiology
https://www.readbyqxmd.com/read/28638805/increased-zinc-availability-enhances-initial-aggregation-and-biofilm-formation-of-streptococcus-pneumoniae
#8
Lindsey R Brown, Rachel C Caulkins, Tyler E Schartel, Jason W Rosch, Erin S Honsa, Stacey Schultz-Cherry, Victoria A Meliopoulos, Sean Cherry, Justin A Thornton
Bacteria growing within biofilms are protected from antibiotics and the immune system. Within these structures, horizontal transfer of genes encoding virulence factors, and promoting antibiotic resistance occurs, making biofilms an extremely important aspect of pneumococcal colonization and persistence. Identifying environmental cues that contribute to the formation of biofilms is critical to understanding pneumococcal colonization and infection. Iron has been shown to be essential for the formation of pneumococcal biofilms; however, the role of other physiologically important metals such as copper, zinc, and manganese has been largely neglected...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28626738/streptococcus-pneumoniae-serotype-prevalence-and-antibiotic-resistance-among-young-children-with-invasive-pneumococcal-disease-experience-from-a-tertiary-care-center-in-south-india
#9
Savitha Nagaraj, Bhuvanesh Sukhlal Kalal, Anand Manoharan, Anita Shet
INTRODUCTION: We performed a study to describe the clinical profile, antimicrobial susceptibility and prevalent serotypes of pneumococcal isolates from children with suspected invasive pneumococcal disease (IPD) admitted to a tertiary care hospital in South India. METHODS: Hospitalized children, ≤ 5 years with fever (>38 °C); increased respiratory rate or neurological symptoms were recruited, (as part of the Alliance for Surveillance of Invasive Pneumococci - ASIP - project) from January 2011 to March 2013...
June 2017: Germs
https://www.readbyqxmd.com/read/28618091/bacterial-transformation-comfa-is-a-dna-dependent-atpase-that-forms-complexes-with-comfc-and-dpra
#10
Amy Diallo, Hannah R Foster, Katarzyna A Gromek, Thomas N Perry, Annick Dujeancourt, Petya V Krasteva, Francesca Gubellini, Tanya G Falbel, Briana M Burton, Rémi Fronzes
Pneumococcal natural transformation contributes to genomic plasticity, antibiotic resistance development, and vaccine escape. Streptococcus pneumoniae, like many other naturally transformable species, has evolved sophisticated protein machinery for the binding and uptake of DNA. Two proteins encoded by the comF operon, ComFA and ComFC, are involved in transformation but their exact molecular roles remain unknown. In this study, we provide experimental evidence that ComFA binds to single stranded DNA (ssDNA) and has ssDNA-dependent ATPase activity...
June 15, 2017: Molecular Microbiology
https://www.readbyqxmd.com/read/28616365/streptococcus-pneumoniae-otitis-media-pathogenesis-and-how-it-informs-our-understanding-of-vaccine-strategies
#11
REVIEW
Caroline Bergenfelz, Anders P Hakansson
PURPOSE OF REVIEW: This study aimed to review the literature regarding the mechanisms of transition from asymptomatic colonization to induction of otitis media and how the insight into the pathogenesis of otitis media has the potential to help design future otitis media-directed vaccines. RECENT FINDINGS: Respiratory viruses have long been shown to predispose individuals to bacterial respiratory infections, such as otitis media. Recent information suggests that Streptococcus pneumoniae, which colonize the nasopharynx asymptomatically, can sense potentially "threatening" changes in the nasopharyngeal environment caused by virus infection by upregulating specific sets of genes involved in biofilm release, dissemination from the nasopharynx to other sites, and protection against the host immune system...
2017: Current Otorhinolaryngology Reports
https://www.readbyqxmd.com/read/28605238/mucin-1-protects-against-severe-streptococcus-pneumoniae-infection
#12
Poshmaal Dhar, Garrett Z Ng, Eileen M Dunne, Philip Sutton
Streptococcus pneumoniae is a bacterial pathogen that commonly resides in the human nasopharynx, typically without causing any disease. However, in some cases these bacteria migrate from the nasopharynx to other sites of the body such as the lungs and bloodstream causing pneumonia and sepsis, respectively. This study used a mouse model of infection to investigate the potential role of Mucin 1 (MUC1), a cell membrane-associated glycoprotein known for playing a key barrier role at mucosal surfaces, in regulating this process...
June 12, 2017: Virulence
https://www.readbyqxmd.com/read/28602840/rational-selection-of-broadly-cross-reactive-family-2-pspa-molecules-for-inclusion-in-chimeric-pneumococcal-vaccines
#13
T R Converso, C Goulart, D Rodriguez, M Darrieux, L C C Leite
Pneumococcal surface protein A (PspA) is a widely studied pneumococcal protein, exposed at the surface of all strains. It is an important virulence factor, preventing complement deposition as well as inhibiting the lytic effects of lactoferrin over pneumococci. Several studies have investigated the use of PspA as a candidate in alternative pneumococcal vaccines, with great success. However, PspA presents sequence variability - there are six clades, grouped in three families - and PspAs within the same clade exhibit different levels of cross-reactivity...
June 7, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28601872/il-37-causes-excessive-inflammation-and-tissue-damage-in-murine-pneumococcal-pneumonia
#14
Anja E Schauer, Tilman E Klassert, Carolin von Lachner, Diana Riebold, Anne Schneeweiß, Magdalena Stock, Mario M Müller, Sven Hammerschmidt, Philip Bufler, Ulrike Seifert, Kristina Dietert, Charles A Dinarello, Marcel F Nold, Achim D Gruber, Claudia A Nold-Petry, Hortense Slevogt
Streptococcus pneumoniae infections can lead to severe complications with excessive immune activation and tissue damage. Interleukin-37 (IL-37) has gained importance as a suppressor of innate and acquired immunity, and its effects have been therapeutic as they prevent tissue damage in autoimmune and inflammatory diseases. By using RAW macrophages, stably transfected with human IL-37, we showed a 70% decrease in the cytokine levels of IL-6, TNF-α, and IL-1β, and a 2.2-fold reduction of the intracellular killing capacity of internalized pneumococci in response to pneumococcal infection...
2017: Journal of Innate Immunity
https://www.readbyqxmd.com/read/28596944/cody-regulates-thiol-peroxidase-expression-as-part-of-the-pneumococcal-defense-mechanism-against-h2o2-stress
#15
Barak Hajaj, Hasan Yesilkaya, Sulman Shafeeq, Xiangyun Zhi, Rachel Benisty, Shiran Tchalah, Oscar P Kuipers, Nurith Porat
Streptococcus pneumoniae is a facultative anaerobic pathogen. Although it maintains fermentative metabolism, during aerobic growth pneumococci produce high levels of H2O2, which can have adverse effects on cell viability and DNA, and influence pneumococcal interaction with its host. The pneumococcus is unusual in its dealing with toxic reactive oxygen species (ROS) in that it neither has catalase nor the global regulators of peroxide stress resistance. Previously, we identified pneumococcal thiol peroxidase (TpxD) as the key enzyme for enzymatic removal of H2O2, and showed that TpxD synthesis is up-regulated upon exposure to H2O2...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28592301/pneumococcal-meningitis-with-normal-cerebrospinal-biochemistry-and-no-pneumococci-at-microscopy-mimicking-a-stroke-a-case-report
#16
Gideon Ertner, Jeppe Romme Christensen, Christian T Brandt
BACKGROUND: Bacterial meningitis commonly presents with symptoms such as headache, impaired consciousness, neck stiffness, and fever. In most cases, cerebrospinal fluid analysis will yield white cell counts >100/mm(3). Atypical presentations occur, especially in the very young or very elderly and the immunocompromised. We report an unusual case of pneumococcal meningitis in a healthy 78-year-old Danish woman who presented with clinical features mimicking a stroke with normal cerebrospinal fluid parameters and without microscopic evidence of bacteria...
June 7, 2017: Journal of Medical Case Reports
https://www.readbyqxmd.com/read/28586394/polyamine-transporter-potabcd-is-required-for-virulence-of-encapsulated-but-not-nonencapsulated-streptococcus-pneumoniae
#17
Haley R Pipkins, Jessica L Bradshaw, Lance E Keller, Edwin Swiatlo, Larry S McDaniel
Streptococcus pneumoniae is commonly found in the human nasopharynx and is the causative agent of multiple diseases. Since invasive pneumococcal infections are associated with encapsulated pneumococci, the capsular polysaccharide is the target of licensed pneumococcal vaccines. However, there is an increasing distribution of non-vaccine serotypes, as well as nonencapsulated S. pneumoniae (NESp). Both encapsulated and nonencapsulated pneumococci possess the polyamine oligo-transport operon (potABCD). Previous research has shown inactivation of the pot operon in encapsulated pneumococci alters protein expression and leads to a significant reduction in pneumococcal murine colonization, but the role of the pot operon in NESp is unknown...
2017: PloS One
https://www.readbyqxmd.com/read/28578394/integrated-proteomic-and-metabolomic-analysis-reveals-that-rhodomyrtone-reduces-the-capsule-in-streptococcus-pneumoniae
#18
Watcharapong Mitsuwan, Alfonso Olaya-Abril, Mónica Calderón-Santiago, Irene Jiménez-Munguía, José Antonio González-Reyes, Feliciano Priego-Capote, Supayang P Voravuthikunchai, Manuel J Rodríguez-Ortega
The emergence of antibiotic-resistant pathogenic bacteria is a healthcare problem worldwide. We evaluated the antimicrobial activity of rhodomyrtone, an acylphloroglucinol present in Rhodomyrtus tomentosa leaves, against the human Gram-positive pathogen Streptococcus pneumoniae. The compound exhibited pronounced anti-pneumococcal activity against a broad collection of clinical isolates. We studied the effects at the molecular level by integrated proteomic and metabolomic analysis. The results revealed alterations in enzymes and metabolites involved in several metabolic pathways including amino acid biosynthesis, nucleic acid biosynthesis, glucid, and lipid metabolism...
June 2, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28557543/impaired-mitochondrial-microbicidal-responses-in-chronic-obstructive-pulmonary-disease-macrophages
#19
Martin A Bewley, Julie A Preston, Mohammed Mohasin, Helen M Marriott, Richard C Budd, Julie Swales, Paul Collini, David R Greaves, Ruth W Craig, Christopher E Brightling, Louise E Donnelly, Peter J Barnes, Dave Singh, Steven D Shapiro, Moira K B Whyte, David H Dockrell
RATIONALE: Chronic obstructive pulmonary disease (COPD) is characterized by impaired clearance of pulmonary bacteria. OBJECTIVES: The effect of COPD on alveolar macrophage (AM) microbicidal responses was investigated. METHODS: Alveolar macrophages (AMs) were obtained from bronchoalveolar lavage from healthy donors or COPD patients and challenged with opsonized serotype 14 Streptococcus pneumoniae. Cells were assessed for apoptosis, bactericidal activity and mitochondrial reactive oxygen species (mROS) production...
May 30, 2017: American Journal of Respiratory and Critical Care Medicine
https://www.readbyqxmd.com/read/28550292/proteomic-comparisons-of-opaque-and-transparent-variants-of-streptococcus-pneumoniae-by-two-dimensional-differential-gel-electrophoresis
#20
Melissa H Chai, Florian Weiland, Richard M Harvey, Peter Hoffmann, Abiodun D Ogunniyi, James C Paton
Streptococcus pneumoniae (the pneumococcus) is a human pathogen, accounting for massive global morbidity and mortality. Although asymptomatic colonization of the nasopharynx almost invariably precedes disease, the critical determinants enabling pneumococcal progression from this niche to cause invasive disease are poorly understood. One mechanism proposed to be central to this transition involves opacity phase variation, whereby pneumococci harvested from the nasopharynx are typically transparent, while those simultaneously harvested from the blood are opaque...
May 26, 2017: Scientific Reports
keyword
keyword
34120
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"