keyword
MENU ▼
Read by QxMD icon Read
search

hypervirulent

keyword
https://www.readbyqxmd.com/read/28494709/hypervirulent-klebsiella-pneumoniae-in-california-sea-lions-zalophus-californianus-pathologic-findings-in-natural-infections
#1
Mauricio Seguel, Nicole L Gottdenker, Kathleen Colegrove, Shawn Johnson, Carsten Struve, Elizabeth W Howerth
Tissues of stranded California sea lions ( Zalophus californianus) naturally infected with a hyperviruluent strain of Klebsiella pneumoniae were examined by histopathology and immunohistochemistry against the K. pneumoniae K2 capsular antigen. In 7 of 8 animals, there was severe purulent bronchopneumonia, sometimes complicated by fibrinonecrotizing pleuritis with pyothorax. In affected areas of lung, large numbers of degenerate neutrophils and macrophages were admixed with rare large extracellular and intracellular gram-negative bacilli surrounded by a prominent capsule...
January 1, 2017: Veterinary Pathology
https://www.readbyqxmd.com/read/28484429/protective-effect-of-carvacrol-against-gut-dysbiosis-and-clostridium-difficile-associated-disease-in-a-mouse-model
#2
Shankumar Mooyottu, Genevieve Flock, Abhinav Upadhyay, Indu Upadhyaya, Kendra Maas, Kumar Venkitanarayanan
This study investigated the effect of carvacrol (CR), a phytophenolic compound on antibiotic-associated gut dysbiosis and C. difficile infection in a mouse model. Five to six-week-old C57BL/6 mice were randomly divided into seven treatment groups (challenge and control) of eight mice each. Mice were fed with irradiated feed supplemented with CR (0, 0.05, and 0.1%); the challenge groups were made susceptible to C. difficile by orally administering an antibiotic cocktail in water and an intra-peritoneal injection of clindamycin...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28482027/cmr-is-a-redox-responsive-regulator-of-dosr-that-contributes-to-m-tuberculosis-virulence
#3
Laura J Smith, Aleksandra Bochkareva, Matthew D Rolfe, Debbie M Hunt, Christina Kahramanoglou, Yvonne Braun, Angela Rodgers, Alix Blockley, Stephen Coade, Kathryn E A Lougheed, Nor Azian Hafneh, Sarah M Glenn, Jason C Crack, Nick E Le Brun, José W Saldanha, Vadim Makarov, Irene Nobeli, Kristine Arnvig, Galina V Mukamolova, Roger S Buxton, Jeffrey Green
Mycobacterium tuberculosis (MTb) is the causative agent of pulmonary tuberculosis (TB). MTb colonizes the human lung, often entering a non-replicating state before progressing to life-threatening active infections. Transcriptional reprogramming is essential for TB pathogenesis. In vitro, Cmr (a member of the CRP/FNR super-family of transcription regulators) bound at a single DNA site to act as a dual regulator of cmr transcription and an activator of the divergent rv1676 gene. Transcriptional profiling and DNA-binding assays suggested that Cmr directly represses dosR expression...
May 8, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28481721/s-oralis-activates-the-efg1-filamentation-pathway-in-c-albicans-to-promote-cross-kingdom-interactions-and-mucosal-biofilms
#4
Hongbin Xu, Takanori Sobue, Martinna Bertolini, Angela Thompson, Margaret Vickerman, Clarissa J Nobile, Anna Dongari-Bagtzoglou
Candida albicans and Streptococcus oralis are ubiquitous oral commensal organisms. Under host-permissive conditions these organisms can form hypervirulent mucosal biofilms. C. albicans biofilm formation is controlled by six master transcriptional regulators: Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1. The objective of this work was to test whether any of these regulators play a role in cross-kingdom interactions between C. albicans and S. oralis in oral mucosal biofilms, and identify downstream target gene(s) that promote these interactions...
May 8, 2017: Virulence
https://www.readbyqxmd.com/read/28463987/the-emergence-of-clostridium-difficile-infection-in-asia-a-systematic-review-and-meta-analysis-of-incidence-and-impact
#5
Nienke Z Borren, Shadi Ghadermarzi, Susan Hutfless, Ashwin N Ananthakrishnan
BACKGROUND: Clostridium difficile infection (CDI) is the most common healthcare associated infection and is highly prevalent in Europe and North America. Limited data is available on the prevalence of CDI in Asia. However, secular increases in prevalence of risk factors for CDI suggest that it may be emerging as a major cause of morbidity, highlighting the urgent need for a systematic study of the prevalence of CDI in Asia. METHODS: We systematically searched PubMed/Medline and Embase for publications from Asia between 2000-16 examining prevalence of CDI...
2017: PloS One
https://www.readbyqxmd.com/read/28450867/p2x7-receptor-in-bone-marrow-derived-cells-aggravates-tuberculosis-caused-by-hypervirulent-mycobacterium-bovis
#6
Caio César Barbosa Bomfim, Eduardo Pinheiro Amaral, Alexandra Dos Anjos Cassado, Érika Machado Salles, Rogério Silva do Nascimento, Elena Lasunskaia, Mario Hiroyuki Hirata, José Maria Álvarez, Maria Regina D'Império-Lima
Tuberculosis (TB) remains a serious public health problem despite the great scientific advances in the recent decades. We have previously shown that aggressive forms of TB caused by hypervirulent strains of Mycobacterium tuberculosis and Mycobacterium bovis are attenuated in mice lacking the P2X7 receptor, an ion channel activated by extracellular ATP. Therefore, P2X7 receptor is a potential target for therapeutic intervention. In vitro, hypervirulent mycobacteria cause macrophage death by a P2X7-dependent mechanism that facilitates bacillus dissemination...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28439781/batrachochytrium-dendrobatidis-and-the-decline-and-survival-of-the-relict-leopard-frog
#7
Jef R Jaeger, Anthony W Waddle, Rebeca Rivera, D Tyler Harrison, Silas Ellison, Matthew J Forrest, Vance T Vredenburg, Frank van Breukelen
Epizootic disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) is a major driver of amphibian declines, yet many amphibians declined before the pathogen was described. The Relict Leopard Frog, Rana onca (=Lithobates onca), was nearly extinct, with the exception of populations within a few geothermal springs. Growth of Bd, however, is limited by high water temperature, and geothermal springs may have provided refuge during outbreaks of chytridiomycosis. We conducted field surveys and laboratory experiments to assess the susceptibility of R...
April 24, 2017: EcoHealth
https://www.readbyqxmd.com/read/28409125/colibactin-contributes-to-the-hypervirulence-of-pks-k1-cc23-klebsiella-pneumoniae-in-mouse-meningitis-infections
#8
Min-Chi Lu, Ying-Tsong Chen, Ming-Ko Chiang, Yao-Chen Wang, Pei-Yi Hsiao, Yi-Jhen Huang, Ching-Ting Lin, Ching-Chang Cheng, Chih-Lung Liang, Yi-Chyi Lai
Klebsiella pneumoniae is the most common pathogen of community-acquired meningitis in Taiwan. However, the lack of a physiologically relevant meningitis model for K. pneumoniae has impeded research into its pathogenesis mechanism. Based on the core genome MLST analyses, the hypervirulent K1 K. pneumoniae strains, which are etiologically implicated in adult meningitis, mostly belong to a single clonal complex, CC23. Some K1 CC23 K. pneumoniae strains carry a gene cluster responsible for colibactin production...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/28402698/hypervirulence-and-hypermucoviscosity-two-different-but-complementary-klebsiella-spp-phenotypes
#9
Juan Carlos Catalán-Nájera, Ulises Garza-Ramos, Humberto Barrios-Camacho
Since the hypermucoviscous variants of Klebsiella pneumoniae were first reported, many cases of primary liver abscesses and other invasive infections caused by this pathogen have been described worldwide. Hypermucoviscosity is a phenotypic feature characterized by the formation of a viscous filament ≥5 mm when a bacterial colony is stretched by a bacteriological loop; this is the so-called positive string test. Hypermucoviscosity appears to be associated with this unusual and aggressive type of infection, and therefore, the causal strains are considered hypervirulent...
April 12, 2017: Virulence
https://www.readbyqxmd.com/read/28400757/streptococcus-agalactiae-causing-neonatal-infections-in-portugal-2005-2015-diversification-and-emergence-of-a-cc17-pi-2b-multidrug-resistant-sublineage
#10
Elisabete R Martins, Cristiano Pedroso-Roussado, José Melo-Cristino, Mário Ramirez
The molecular characterization of 218 GBS isolates recovered from neonatal invasive infections in Portugal in 2005-2015 revealed the existence of a small number of genetically distinct lineages that were present over a significant time-span. Serotypes III and Ia were dominant in the population, together accounting for >80% of the isolates. Clonal complex 17 included 50% of all isolates, highlighting the importance of the hypervirulent genetic lineage represented by serotype III ST17/rib/PI-1+PI-2b. Serotype Ia was represented mainly by ST23, previously reported as dominant among invasive disease in non-pregnant adults in Portugal, but also by ST24, showing an increased frequency among late-onset disease...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28396132/clostridium-difficile-infection
#11
REVIEW
Luis Alcalá Hernández, Elena Reigadas Ramírez, Emilio Bouza Santiago
Clostridium difficile infection (CDI) is the main cause of nosocomial diarrhea in industrialized countries and the source of a growing number of cases of diarrhea in the community. The outbreak of the hypervirulent strain belonging to ribotype 027 has increased the incidence and severity of CDI in some countries. Although CDI usually courses as a mild diarrhea it can lead to severe forms such as toxic megacolon or septic shock. One of every 2 episodes of CDI is not diagnosed in Spanish hospitals due to a lack of clinical suspicion or the use of insensitive diagnostic methods...
April 8, 2017: Medicina Clínica
https://www.readbyqxmd.com/read/28392922/first-report-of-invasive-liver-abscess-syndrome-with-endophthalmitis-caused-by-a-k2-serotype-st2398-hypervirulent-klebsiella-pneumoniae-in-germany-2016
#12
C Pichler, M Büchsel, J W Rossen, M Vavra, S Reuter, W V Kern, R Thimme, A Mischnik
We report a case of severe infection with liver abscess and endophthalmitis caused by a hypervirulent Klebsiella pneumoniae strain in an immunocompetent German male patient without travel history to Asia. Phenotypic and molecular characterization showed high similarity to the reference genome NTUH-K2044 isolated in Asia. The isolate was assigned as ST2398 (clonal complex 66). The findings underline global spread of hypervirulent Klebsiella pneumoniae strains to Europe.
May 2017: New Microbes and New Infections
https://www.readbyqxmd.com/read/28384318/correction-hypervirulent-mycobacterium-tuberculosis-strain-triggers-necrotic-lung-pathology-associated-with-enhanced-recruitment-of-neutrophils-in-resistant-c57bl-6-mice
#13
Fabrício M Almeida, Thatiana L B Ventura, Eduardo P Amaral, Simone C M Ribeiro, Sanderson D Calixto, Marcelle R Manhães, Andreza L Rezende, Giliane S Souza, Igor S de Carvalho, Elisangela C Silva, Juliana Azevedo da Silva, Eulógio C Q Carvalho, Afranio L Kritski, Elena B Lasunskaia
[This corrects the article DOI: 10.1371/journal.pone.0173715.].
2017: PloS One
https://www.readbyqxmd.com/read/28383686/cluster-of-fatal-group-a-streptococcal-emm87-infection-within-a-single-family-molecular-basis-for-invasion-and-transmission
#14
Anthony R Flores, Ruth Ann Luna, Jessica K Runge, Samuel A Shelburne, Carol J Baker
Hypervirulent disease due to group A Streptococcus (GAS) can result from strains with mutations that enhance virulence gene expression but reduce subsequent transmission. We used whole genome sequencing to investigate intra-familial spread between 4 siblings of a hypervirulent GAS strain resulting in a fatality. All invasive and pharyngeal GAS isolates had an identical mutation in a gene encoding a key regulatory protein that yielded a hyperinvasive phenotype. These data challenge the prevailing theory of reduced transmission induced by mutations that lead to hypervirulent GAS by showing that spread of hypervirulent GAS may lead to clusters of invasive disease...
April 5, 2017: Journal of Infectious Diseases
https://www.readbyqxmd.com/read/28379411/comparison-of-the-inflammatory-response-of-brain-microvascular-and-peripheral-endothelial-cells-following-infection-with-neisseria-meningitidis
#15
Julia Dick, Sabrina Hebling, Jérôme Becam, Muhamed-Kheir Taha, Alexandra Schubert-Unkmeir
The interaction of Neisseria meningitidis with both peripheral and brain endothelial cells is a critical event in the development of invasive meningococcal disease. In this study, we used in vitro models based on human brain microvascular endothelial cells (HBMEC), and peripheral endothelial EA.hy926 cells, to investigate their roles in the inflammatory response towards meningococcal infection. Both cell lines were infected with two pathogenic N. meningitidis isolates and secretion of the cytokine interleukin-6 (IL-6), the CXC chemokine IL-8 and the monocyte chemoattractant protein-1 (MCP-1) were estimated by ELISA...
April 1, 2017: Pathogens and Disease
https://www.readbyqxmd.com/read/28375514/clinical-implications-of-genomic-adaptation-and-evolution-of-carbapenem-resistant-klebsiella-pneumoniae
#16
REVIEW
Angela Gomez-Simmonds, Anne-Catrin Uhlemann
Klebsiella pneumoniae poses a major challenge to healthcare worldwide as an important cause of multidrug-resistant infections. Nosocomial clones, including epidemic sequence type 258 (ST258), have shown an affinity for acquiring and disseminating resistance plasmids, particularly variants of the K. pneumoniae carbapenemase. By comparison, the resurgence of severe community-associated K. pneumoniae infections has led to increased recognition of hypervirulent strains belonging to the K1 and K2 capsular serotypes, predominantly in eastern Asia...
February 15, 2017: Journal of Infectious Diseases
https://www.readbyqxmd.com/read/28373547/emergence-of-a-new-neisseria-meningitidis-clonal-complex-11-lineage-11-2-clade-as-an-effective-urogenital-pathogen
#17
Yih-Ling Tzeng, Jose A Bazan, Abigail Norris Turner, Xin Wang, Adam C Retchless, Timothy D Read, Evelyn Toh, David E Nelson, Carlos Del Rio, David S Stephens
Neisseria meningitidis (Nm) clonal complex 11 (cc11) lineage is a hypervirulent pathogen responsible for outbreaks of invasive meningococcal disease, including among men who have sex with men, and is increasingly associated with urogenital infections. Recently, clusters of Nm urethritis have emerged primarily among heterosexual males in the United States. We determined that nonencapsulated meningococcal isolates from an ongoing Nm urethritis outbreak among epidemiologically unrelated men in Columbus, Ohio, are linked to increased Nm urethritis cases in multiple US cities, including Atlanta and Indianapolis, and that they form a unique clade (the US Nm urethritis clade, US_NmUC)...
April 18, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28373351/key-role-of-capsular-polysaccharide-in-the-induction-of-systemic-infection-and-abortion-by-hypervirulent-campylobacter-jejuni
#18
Orhan Sahin, Samantha A Terhorst, Eric R Burrough, Zhangqi Shen, Zuowei Wu, Lei Dai, Yizhi Tang, Paul J Plummer, Ju Ji, Michael J Yaeger, Qijing Zhang
Campylobacter jejuni is a zoonotic pathogen, and a hypervirulent strain, named clone SA, has recently emerged as the predominant cause of ovine abortion in the United States. To induce abortion, orally ingested Campylobacter must translocate across the intestinal epithelium, spread systemically in the circulation, and reach the fetoplacental tissue. Bacterial factors involved in these steps are not well understood. C. jejuni is known to produce capsular polysaccharide (CPS), but the specific role CPS plays in systemic infection and particularly abortion in animals remains to be determined...
April 3, 2017: Infection and Immunity
https://www.readbyqxmd.com/read/28366569/development-of-a-dose-assay-for-a-clostridium-difficile-vaccine-using-a-tandem-ion-exchange-high-performance-liquid-chromatography-method
#19
Feng Wang, Sha Ha, Richard R Rustandi
Clostridium difficile is a gram-positive intestine bacterium that causes a severe diarrhea and could eventually be lethal. The main virulence factor is related to the release of two major exotoxins, toxin A (TcdA) and toxin B (TcdB). Recent C. difficile-associated disease (CDAD) outbreaks have been caused by hypervirulent strains which secrete an additional binary toxin (CDTa/CDTb). Vaccination against these toxins is considered the best way to combat the CDAD. Recently, a novel tetravalent C. difficile vaccine candidate containing all four toxins produced from a baculovirus expression system has been developed...
March 21, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28363494/clinical-and-endoscopic-features-in-patients-with-hospital-acquired-diarrhea-associated-with-clostridium-difficile-infection
#20
J A Velarde Ruiz-Velasco, J M Aldana-Ledesma, M A Ibarra-Estrada, S A Aguirre Díaz, J A Fernández-Ramírez, F Cárdenas-Lara, F Álvarez López, L E Rodríguez-Noriega, H R Pérez-Gómez, M R Morfín-Otero
BACKGROUND AND AIMS: Clostridium difficile (CD) is the leading cause of hospital-acquired diarrhea. Clinical and endoscopic findings are poorly described in our country. The aim of this study is to depict those findings. MATERIAL AND METHODS: Prospective cohort study, which included patients with CD associated hospital-acquired diarrhea, diagnosed by means of fecal PCR and testing for the presence of hypervirulent strain NAP027. We analyzed clinical and endoscopic features, as well as the variables associated with severe disease...
March 28, 2017: Revista de Gastroenterología de México
keyword
keyword
79828
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"