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Pneumococci

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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
#1
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
#2
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
#3
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
#4
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
#5
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
#6
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...
June 10, 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
#7
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
#8
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
#9
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
#10
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
#11
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
#12
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
https://www.readbyqxmd.com/read/28542565/promiscuous-signaling-by-a-regulatory-system-unique-to-the-pandemic-pmen1-pneumococcal-lineage
#13
Anagha Kadam, Rory A Eutsey, Jason Rosch, Xinyu Miao, Mark Longwell, Wenjie Xu, Carol A Woolford, Todd Hillman, Anfal Shakir Motib, Hasan Yesilkaya, Aaron P Mitchell, N Luisa Hiller
Streptococcus pneumoniae (pneumococcus) is a leading cause of death and disease in children and elderly. Genetic variability among isolates from this species is high. These differences, often the product of gene loss or gene acquisition via horizontal gene transfer, can endow strains with new molecular pathways, diverse phenotypes, and ecological advantages. PMEN1 is a widespread and multidrug-resistant pneumococcal lineage. Using comparative genomics we have determined that a regulator-peptide signal transduction system, TprA2/PhrA2, was acquired by a PMEN1 ancestor and is encoded by the vast majority of strains in this lineage...
May 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/28516866/invasive-serotype-35b-pneumococci-including-an-expanding-serotype-switch-lineage-united-states-2015-2016
#14
Sopio Chochua, Benjamin J Metcalf, Zhongya Li, Hollis Walker, Theresa Tran, Lesley McGee, Bernard Beall
We used whole-genome sequencing to characterize 199 nonvaccine serotype 35B pneumococcal strains that caused invasive pneumococcal disease (IPD) in the United States during 2015-2016 and related these findings to previous serotype 35B IPD data obtained by Active Bacterial Core surveillance. Penicillin-nonsusceptible 35B IPD increased during post-pneumococcal 7-valent conjugate vaccine years (2001-2009) and increased further after implementation of pneumococcal 13-valent conjugate vaccine in 2010. This increase was caused primarily by the 35B/sequence type (ST) 558 lineage...
June 2017: Emerging Infectious Diseases
https://www.readbyqxmd.com/read/28516842/serotype-distribution-antimicrobial-resistance-and-prevalence-of-pilus-islets-in-pneumococci-following-the-use-of-conjugate-vaccines
#15
Mitsuyo Kawaguchiya, Noriko Urushibara, Meiji Soe Aung, Masaaki Shinagawa, Satoshi Takahashi, Nobumichi Kobayashi
PURPOSE: In Japan, the 7-valent pneumococcal vaccine (PCV7) was introduced in 2010 and, in 2013, the PCV7 was replaced with the 13-valent pneumococcal vaccine (PCV13). This study was conducted to investigate serotypes, antimicrobial resistance and prevalence of pilus islets in pneumococcal isolates from inpatients in a Japanese tertiary hospital. METHODOLOGY: From April 2011 to February 2016, 151 isolates [95 (18 children, 77 adults) and 56 (19 children, 37 adults) in the PCV7 and PCV13 periods, respectively] were collected...
May 2017: Journal of Medical Microbiology
https://www.readbyqxmd.com/read/28516066/the-alpha-tocopherol-form-of-vitamin-e-boosts-elastase-activity-of-human-pmns-and-their-ability-to-kill-streptococcus-pneumoniae
#16
Elsa N Bou Ghanem, James N Lee, Basma H Joma, Simin N Meydani, John M Leong, Alexander Panda
Despite the availability of vaccines, Streptococcus pneumoniae remains a leading cause of life-threatening infections, such as pneumonia, bacteremia and meningitis. Polymorphonuclear leukocytes (PMNs) are a key determinant of disease course, because optimal host defense requires an initial robust pulmonary PMN response to control bacterial numbers followed by modulation of this response later in infection. The elderly, who manifest a general decline in immune function and higher basal levels of inflammation, are at increased risk of developing pneumococcal pneumonia...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28515075/pigr-and-pecam-1-bind-to-pneumococcal-adhesins-rrga-and-pspc-mediating-bacterial-brain-invasion
#17
Federico Iovino, Joo-Yeon Engelen-Lee, Matthijs Brouwer, Diederik van de Beek, Arie van der Ende, Merche Valls Seron, Peter Mellroth, Sandra Muschiol, Jan Bergstrand, Jerker Widengren, Birgitta Henriques-Normark
Streptococcus pneumoniae is the main cause of bacterial meningitis, a life-threating disease with a high case fatality rate despite treatment with antibiotics. Pneumococci cause meningitis by invading the blood and penetrating the blood-brain barrier (BBB). Using stimulated emission depletion (STED) super-resolution microscopy of brain biopsies from patients who died of pneumococcal meningitis, we observe that pneumococci colocalize with the two BBB endothelial receptors: polymeric immunoglobulin receptor (pIgR) and platelet endothelial cell adhesion molecule (PECAM-1)...
June 5, 2017: Journal of Experimental Medicine
https://www.readbyqxmd.com/read/28511165/susceptibility-of-streptococcus-pneumoniae-to-fluoroquinolones-and-macrolides-in-upper-respiratory-tract-infections
#18
Yaroslav O Mykhalko, Tetyana V Duhovych, Pavlo P Kish
INTRODUCTION: Streptococcal species are known as the most common cause of bacterial upper respiratory tract infections (URTI). Once bacterial infection is diagnosed it demands empirical antibiotic prescription. On the other hand antimicrobial resistance is a global burden in today's medicine. For that reason, knowing of antimicrobial susceptibility patterns in population is an important background for successful treatment of bacterial caused URTI. The aim of this study was to analyze S...
2017: Wiadomości Lekarskie: Organ Polskiego Towarzystwa Lekarskiego
https://www.readbyqxmd.com/read/28489454/acquisition-and-transmission-of-streptococcus-pneumoniae-is-facilitated-during-rhinovirus-infection-in-families-with-children
#19
Sinikka Karppinen, Johanna Teräsjärvi, Kari Auranen, Linnea Schuez-Havupalo, Lotta Siira, Qiushui He, Matti Waris, Ville Peltola
RATIONALE: Laboratory and clinical evidence suggests synergy between rhinoviruses and Streptococcus pneumoniae in the pathogenesis of respiratory tract infections. However, it is unclear whether rhinoviruses promote pneumococcal acquisition and transmission. OBJECTIVES: To describe the impact of rhinovirus infection on acquisition and transmission of pneumococci within families with children. METHODS: We investigated 29 families with at least two children...
May 10, 2017: American Journal of Respiratory and Critical Care Medicine
https://www.readbyqxmd.com/read/28487056/polysaccharide-conjugate-vaccine-protein-carriers-as-a-neglected-valency-potential-and-limitations
#20
REVIEW
Michael Bröker, Francesco Berti, Joerg Schneider, Ivo Vojtek
The development of vaccines against polysaccharide-encapsulated pathogens (e.g. Haemophilus influenzae type b, pneumococci, meningococci) is challenging because polysaccharides do not elicit a strong and long-lasting immune response (i.e. T-cell independent). This can be overcome by conjugating the polysaccharide to a protein carrier (e.g. tetanus toxoid, cross-reacting material 197 [CRM]), which vastly improves the immune response and induces memory to the polysaccharide (T-cell dependent). Although it is well documented that protein carriers additionally induce an immune response against themselves, this potential "additional valency" has so far not been recognized...
June 5, 2017: Vaccine
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