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Bernard Louizette Christophe, Mariana Mott, Gabriela da Cunha, Juliana Caierão, Pedro D Azevedo, Cícero Dias
PURPOSE: Invasive pneumococcal disease (IPD) in the elderly is an important public health issue due to the increased proportion of this population in many countries including Brazil. We aimed to characterise pneumococci isolates in adults >50 years with IPD, following the introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) as part of the National Childhood Immunisation Program for children ≤2 years in March 2010. METHODOLOGY: Between 2013 and 2015, pneumococcal isolates were collected and serotypes were determined using multiplex PCR and/or Quellung reaction...
March 13, 2018: Journal of Medical Microbiology
Faidad Khan, Mohsin Ahmad Khan, Nadeem Ahmed, Muhammad Islam Khan, Hamid Bashir, Saad Tahir, Ahmad Usman Zafar
INTRODUCTION: Pakistan has one of the highest burdens of pneumococcal diseases in the world, but unfortunately studies in this demanding research area are limited in the region. Pneumococcal surface protein A (PspA) is the next generation pneumococcal vaccine candidate as the protein locates on the Streptococcus pneumoniae surface. Its gene, pspA, might be encoded by all pneumococci, and the protein has proven immunogenicity. The molecular characterization of PspA, pneumococcal serotype distribution and antibiotic susceptibility are important for regional diversity studies...
March 9, 2018: Infectious Diseases and Therapy
Dandan Wang, Jingcai Lu, Jinfei Yu, Hongjia Hou, Kees Leenhouts, Maarten L Van Roosmalen, Tiejun Gu, Chunlai Jiang, Wei Kong, Yongge Wu
BACKGROUND: Streptococcus pneumoniae is a major pathogen accounting for a large number of pneumococcal disease in worldwide. Due to the mucosal immune pathway induces both systemic and mucosal immune responses, the potential strategy to prevent pneumococcal disease may be to develop a mucosal vaccine. METHOD: In this study, we developed an intranasal pneumococcal protein vaccine based on a bacterium-like particle (BLP) delivery system. PspA is expressed and exposed on the surface of all pneumococcal strains, which confers the potential to induce immune responses to protect against pneumococcal infection...
March 2, 2018: Immunological Investigations
Juliane Hoyer, Jürgen Bartel, Alejandro Gómez-Mejia, Manfred Rohde, Claudia Hirschfeld, Nathalie Heß, Thomas Sura, Sandra Maaß, Sven Hammerschmidt, Dörte Becher
Iron is an essential trace element and involved in various key metabolic pathways in bacterial lifestyle. Within the human host, iron is extremely limited. Hence, the ability of bacteria to acquire iron from the environment is critical for a successful infection. Streptococcus pneumoniae (the pneumococcus) is a human pathobiont colonizing symptomless the human respiratory tract, but can also cause various local and invasive infections. To survive and proliferate pneumococci have therefore to adapt their metabolism and virulence factor repertoire to different host compartments...
February 13, 2018: International Journal of Medical Microbiology: IJMM
Mona Mohammadzadeh, Setareh Mamishi, Babak Pourakbari, Shima Mahmoudi
Despite the availability of relatively effective vaccines, Streptococcus pneumoniae still causes widespread morbidity and mortality. Current vaccines contain free polysaccharides or protein-polysaccharide conjugates, but do not induce protection against serotypes that are not included in the vaccines. Therefore, developing alternative vaccines is of high priority and importance. Several investigators have identified protective antigens common to pneumococci of many or all serotypes. Malley et al. in their study, have recommended unencapsulated whole cells, as an alternative vaccine, a number of such antigens unoccluded by capsule were presented in a native configuration in 2001...
December 2017: Iranian Journal of Microbiology
Tiffany M Zarrella, Dennis W Metzger, Guangchun Bai
Cyclic di-adenosine monophosphate (c-di-AMP) is a newly discovered bacterial second messenger. However, regulation of c-di-AMP homeostasis is poorly understood. In Streptococcus pneumoniae , a sole diadenylate cyclase, CdaA, produces c-di-AMP and two phosphodiesterases, Pde1 and Pde2, cleave the signaling di-nucleotide. To expand our knowledge of the pneumococcal c-di-AMP signaling network, we performed whole genome sequencing of Δ pde1 Δ pde2 heat shock suppressors. In addition to surviving heat shock, these suppressor mutants restored general stress resistance and improved growth in rich medium...
February 26, 2018: Journal of Bacteriology
Agnar Bjarnason, Johan Westin, Magnus Lindh, Lars-Magnus Andersson, Karl G Kristinsson, Arthur Löve, Olafur Baldursson, Magnus Gottfredsson
Background: The microbial etiology of community-acquired pneumonia (CAP) is often unclear in clinical practice, and previous studies have produced variable results. Population-based studies examining etiology and incidence are lacking. This study examined the incidence and etiology of CAP requiring hospitalization in a population-based cohort as well as risk factors and outcomes for specific etiologies. Methods: Consecutive admissions due to CAP in Reykjavik, Iceland were studied...
February 2018: Open Forum Infectious Diseases
Kimiko Ubukata, Miyuki Morozumi, Megumi Sakuma, Misako Takata, Eriko Mokuno, Takeshi Tajima, Satoshi Iwata
BACKGROUND: Acute otitis media (AOM) is a leading cause of childhood morbidity and antibiotic prescriptions. We examined etiologic changes in AOM after introduction of 13-valent pneumococcal conjugate vaccine as routine immunization for Japanese children in 2014. Serotypes, resistance genotypes, antibiotic susceptibilities, and multilocus sequence typing of pneumococcal isolates were also characterized. METHODS: Otolaryngologists prospectively collected middle ear fluid from 582 children by tympanocentesis or sampling through a spontaneously ruptured tympanic membrane between June 2016 and January 2017...
February 22, 2018: Pediatric Infectious Disease Journal
Anshu Shrivastav, Alexander N Dabrowski, Claudia Conrad, Nelli Baal, Holger Hackstein, Stephanie Plog, Kristina Dietert, Achim D Gruber, Philippe D N'Guessan, Sahar Aly, Norbert Suttorp, Janine Zahlten
Pneumococci frequently cause community-acquired pneumonia, a disease with high mortality rates, particularly in young children and in the elderly. Endogenous antimicrobial peptides and proteins such as PGLYRP3 may contribute to the progression and outcome of this disease. Since increasing antibiotic resistant strains occur all over the world, these endogenous antimicrobial molecules are interesting new targets for future therapies. In this study, the expression pattern of PGLYRP3 was analyzed in alveolar epithelial cells, alveolar macrophages and neutrophils...
2018: Frontiers in Microbiology
Beatríz Quintero Moreno, María Araque
We analyzed genetics mechanisms of antibiotics resistance, clonal composition and pili in forty eight MDR-pneumococci isolated from healthy children in Mérida, Venezuela. Intermediate resistance to penicillin was related to variations on pbp2b and pbp2x genes. High-level resistance to penicillin, low susceptibility to cephalosporins and carbapenems were associated with alterations on pbp1a, pbp2b and pbp2x genes. Non-beta-lactam resistance was associated with Tn3872, Tn5253, Tn6002, Tn2010 transposons. Macrolide-resistant strains carried ermB or mefE, but not the mefA gene...
February 12, 2018: Journal of Global Antimicrobial Resistance
Margareta Ieven, Samuel Coenen, Katherine Loens, Christine Lammens, Frank Coenjaerts, Anouk Vanderstraeten, Birgitta Henriques-Normark, Derrick Crook, Kris Huygen, Chris C Butler, Theo Jm Verheij, Paul Little, Kalina Zlateva, Anton van Loon, Eric Cj Claas, Herman Goossens
OBJECTIVES: To describe the role of bacteria (including bacterial resistance), viruses (including those recently described), and mixed bacterial-viral infections in adults presenting to primary care with lower respiratory tract infection (LRTI). METHODS: We enrolled 3104 adults with LRTI, 141 (4.5%) of whom had community-acquired pneumonia (CAP), and 2985 matched controls in a prospective study in 16 primary care networks in Europe, and followed patients up at 28-35 days...
February 12, 2018: Clinical Microbiology and Infection
Joo-Yeon Engelen-Lee, Matthijs C Brouwer, Eleonora Aronica, Diederik van de Beek
BACKGROUND: Delayed cerebral thrombosis (DCT) is a devastating cerebrovascular complication in patients with excellent initial recovery of pneumococcal meningitis. The aetiology is unknown, but direct bacterial invasion, activation of coagulation or post-infectious immunoglobulin deposition has been suggested. METHODS: We studied histopathology of 4 patients with pneumococcal meningitis complicated by DCT. Results were compared with 8 patients who died of pneumococcal meningitis without DCT and 3 non-meningitis control cases...
February 9, 2018: Annals of Intensive Care
Felipe P G Neves, Nayara T Cardoso, Aline R V Souza, Robert E Snyder, Mariel M Marlow, Tatiana C A Pinto, Lúcia M Teixeira, Lee W Riley
Objectives: To determine the population structure and change in drug resistance of pneumococci colonizing children before and after the introduction of the 10-valent and 13-valent pneumococcal conjugate vaccines (PCV10/13) in Brazil. Methods: We used MLST to analyse 256 pneumococcal isolates obtained from children aged <6 years before (2009-10; n = 125) and after (2014; n = 131) the introduction of the PCV10 and PCV13. Antimicrobial susceptibility and capsular types were previously determined...
February 1, 2018: Journal of Antimicrobial Chemotherapy
Anne Leonard, Philipp Gierok, Karen Methling, Alejandro Gómez-Mejia, Sven Hammerschmidt, Michael Lalk
The Gram-positive bacterium Streptococcus pneumoniae can cause a broad range of severe diseases including pneumonia and septicemia. The pneumococcal pathophysiology is highly dependent on host nutrients such as purines, pyrimidines, amino acids and carbon sources. Therefore, we aimed to decipher the metabolome with a metabolomics approach that allows for the investigation of the basic metabolic characteristics during growth in a chemical defined medium composed of typical host metabolites. By using a combination of 1H-NMR, HPLC-MS and GC-MS methods we monitored extracellular uptake and secretion of metabolites as well as the intracellular metabolic composition...
January 3, 2018: International Journal of Medical Microbiology: IJMM
Haley R Pipkins, Jessica L Bradshaw, Lance E Keller, Larry S McDaniel
Background: Current Streptococcus pneumoniae vaccines selectively target capsular polysaccharide of specific serotypes, leading to an increase in nonencapsulated S. pneumoniae (NESp). Cocolonization by encapsulated pneumococci and NESp increases the opportunity of intra-species genetic exchange. Acquisition of NESp genes by encapsulated pneumococci could alter virulence and help vaccine-targeted serotypes persist in the host. Methods: Adhesion and invasion assay were performed using immortalized human pharyngeal or lung epithelial cells...
January 31, 2018: Journal of Infectious Diseases
Erika van der Maten, Bryan van den Broek, Marien I de Jonge, Kim J W Rensen, Marc J Eleveld, Aldert L Zomer, Amelieke J H Cremers, Gerben Ferwerda, Ronald de Groot, Jeroen D Langereis, Michiel van der Flier
Pneumococcal capsular serotype is an important determinant of complement resistance and invasive disease potential, but other virulence factors have also been found to contribute. Pneumococcal surface protein C (PspC), a highly variable virulence protein that binds complement factor H to evade C3 opsonization, is divided into two subgroups: choline-bound subgroup I and LPxTG-anchored subgroup II. The prevalence of different PspC subgroups in invasive pneumococcal disease (IPD) and functional differences in complement evasion are unknown...
January 29, 2018: Infection and Immunity
Joseph A Lewnard, Noga Givon-Lavi, Paula A Tähtinen, Ron Dagan
Background: All-cause otitis media (OM) incidence has declined in numerous settings following introduction of pneumococcal conjugate vaccines (PCVs) despite increases in carriage of non-vaccine pneumococcal serotypes escaping immune pressure. To understand the basis for declining incidence, we assessed the intrinsic capacity of pneumococcal serotypes to cause OM independently and in polymicrobial infections involving nontypeable Haemophilus influenzae (NTHi) using samples obtained from middle ear fluid and nasopharyngeal cultures before PCV7/13 rollout...
January 29, 2018: Infection and Immunity
Paul J Collini, Martin A Bewley, Mohamed Mohasin, Helen M Marriott, Robert F Miller, Anna-Maria Geretti, Apostolos Beloukas, Athanasios Papadimitropoulos, Robert C Read, Mahdad Noursadeghi, David H Dockrell
Rationale People living with HIV (PLWH) are at significantly increased risk of invasive pneumococcal disease, despite long-term antiretroviral therapy (ART). The mechanism explaining this observation remains undefined. Objectives We hypothesized apoptosis-associated microbicidal mechanisms, required to clear intracellular pneumococci that survive initial phagolysosomal killing, are perturbed. Methods Alveolar macrophages (AM) were obtained by bronchoalveolar lavage (BAL) from healthy donors or HIV-1-seropositive donors on long-term ART with undetectable plasma viral load...
January 24, 2018: American Journal of Respiratory and Critical Care Medicine
Mary F Nakamya, Moses B Ayoola, Seongbin Park, Leslie A Shack, Edwin Swiatlo, Bindu Nanduri
Invasive infections caused by Streptococcus pneumoniae, a commensal in the nasopharynx, pose significant risk to human health. Limited serotype coverage by the available polysaccharide-based conjugate vaccines coupled with increasing incidence of antibiotic resistance complicates therapeutic strategies. Bacterial physiology and metabolism that allows pathogens to adapt to the host are a promising avenue for the discovery of novel therapeutics. Intracellular polyamine concentrations are tightly regulated by biosynthesis, transport and degradation...
January 19, 2018: Medical Sciences: Open Access Journal
Satoshi Nakano, Takao Fujisawa, Yutaka Ito, Bin Chang, Yasufumi Matsumura, Masaki Yamamoto, Miki Nagao, Shigeru Suga, Makoto Ohnishi, Satoshi Ichiyama
After the introduction of pneumococcal conjugate vaccines, the incidence of pneumococcal infections due to meropenem-resistant serotype 15A-ST63 strains increased in Japan. By using whole-genome sequencing and comparing sequences with those of clones from the United Kingdom, the United States, and Canada, we clarified the traits of the serotype 15A-ST63 clone. Our analysis revealed that the meropenem-resistant serotype 15A-ST63 strains from Japan originated from meropenem-susceptible strains from Japan. Recombination site prediction analysis showed that the meropenem-resistant strain-specific recombination regions included the pbp1a and pbp2b regions...
February 2018: Emerging Infectious Diseases
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