Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 79 for “"streptococcal"”.
-
Molecular studies on streptococcal surface proteins
… protein of S. pyogenes identifies a family of streptococcal proteins with leucine-rich repeats (LRRs). Characterization of Blr and Slr revealed that the two proteins are efficiently camouflaged by other surface components. In S. agalactiae, exposure of Blr was increased ~100-fold in a mutant …
-
Streptococcal virulence and the coagulation system.
This thesis explores streptococcal virulence from both mechanistic and evolutionary perspectives, where the mechanistic studies focus on interactions with the human coagulation system. We describe interactions between streptococcal surface proteins and components of the intrinsic pathway of …
-
Streptococcal M protein and human C4BP
Antigenic variation of surface proteins allows microorganisms to evade the immune system of the infected host. This phenomenon represents an apparent paradox, because the variable protein must retain an important function, while its antigenic properties vary extensively. The surface associated M …
-
Recurrent Streptococcal Pharyngotonsillitis Studies on etiology and treatment
In acute pharyngotonsillitis group A streptococci (GAS) is the etiological agent in 30-50% of cases. Phenoxymethylpenicillin (pcV) is the drug of choice in Sweden. However, the failure rate is as high as 5-25% and further pcV treatment is followed by still higher failure rates. The background of …
-
Treatment of Group A Beta-Hemolytic Streptococcal tonsillopharyngitis: Cephalosporins Versus Penicillins
<p>Group A beta-hemolytic streptococcal (GABHS) tonsillopharyngitis, also known as strep throat, has been a diagnosis of significant worldwide public health concern for decades. Serious post-infectious complications associated with untreated GABHS tonsillopharyngitis propel prompt diagnosis and …
-
SRV REGULATION OF STREPTOCOCCAL BIOFILM DISPERSAL AND ITS IMPACT ON VIRULENCE
Group A Streptococcus (GAS) is a Gram-positive human pathogen that commonly causes mild skin infections. However, GAS also causes severe infections including necrotizing fasciitis. The mechanism for triggering the switch between mild and severe disease has yet to be discovered. Several groups have …
-
Roles of Group B Streptococcal membrane proteins in virulence and protection
… that may be HtrA regulated, including the novel Streptococcal surface immunogenic protein (Sip). Interestingly, HtrA‘s virulence effect is partially linked to Sip, since deletion of both proteins led to a similar rate of adverse pregnancy outcomes compared to either single deletion. Further, I …
-
Phenotypic and Genotypic Models of Streptococcal Colonization of the Human Tonsil
… of pathogen-host microenvironment effects on streptococcal virulence, the specific interaction between S. pyogenes and the human tonsillar surface relative to neighboring tissues remains insufficiently understood. This thesis investigates the unique interaction between the Group A …
-
Invasive Group B Streptococcal disease in newborns at Groote Schuur Hospital
Background. Group B Streptococcal disease is an important cause of morbidity and mortality in newborns globally, and is more common in Sub-Saharan Africa and South Africa. There are few studies reporting on the burden of invasive Group B Streptococcus disease (iGBS) in newborns in South Africa, …
-
Organization of the Streptococcal ExPortal and its Interaction with Cationic Antimicrobial Peptides
… the importance of secreted virulence proteins to streptococcal pathogenicity, the ExPortal is an attractive target for the development of therapeutics that can efficiently counter streptococcal infections. I investigated the interaction of cationic antimicrobial peptides with the streptococcal …
-
Streptococcal colonization of host mucosal surfaces: a study of biofilm formation and dispersal
Group A <italic>Streptococcus</italic> (GAS) is a Gram-positive pathogen that is the causative agent of a variety of human diseases. Infections include pharyngitis, otitis media, sepsis, a toxic-shock syndrome, necrotizing fasciitis, and the post-infectious sequelae acute rheumatic fever and acute …
-
Functional and Structural Characterisation of Spy0136, a Novel Group A Streptococcal Virulence Factor
Streptococcus pyogenes (Group A Streptococcus, GAS) is a leading human pathogen associated with a broad range of diseases and over half a million deaths annually all over the world. GAS generates numerous virulence factors contributing to the bacteria's pathogenesis. However, the function of many …
-
AFROStrep (SA): a surveillance system for group A streptococcal infection in South Africa
BACKGROUND AND AIMS OF THE THESIS: Group A β-haemolytic Streptococcus (GAS) also known as Streptococcus pyogenes, is responsible for a wide range of invasive and non-invasive GAS diseases. Prevalence and incidence data on GAS from developing countries are largely lacking when compared with …
-
Systems Biology Approach to Identifying Host Interactive Pathways Modulating the Severity of Streptococcal Sepsis
… provided evidence that in invasive Group A streptococcal (GAS) infections, genetic variations in both bacteria and patients influenced the severity of GAS sepsis. Allelic variations in class II human leukocyte antigens (HLA) contributed significantly to differences in the severity of group A …
-
Engineering soluble, high affinity T cell receptor domains for detection of staphylococcal and streptococcal exotoxins
… SEC), toxic shock syndrome toxin-1 (TSST-1) and streptococcal pyrogenic exotoxins (SpeA, SpeC) that possess superantigenic properties, by virtue of which they stimulate a large fraction of an individual’s T cells, leading to hyperinflammation and in some cases, organ failure and death. The …
-
Biochemical and Immunological Mechanisms Underlying Differential Interaction of Superantigens with Host Immunogenetic Factors in Streptococcal Sepsis
… array of diseases ranging from pharyngitis to streptococcal toxic shock (STSS), which is caused by excessive cytokines responses triggered by streptococcal superantigens (Strep SAgs). SAgs interact simultaneously with HLA class II molecules on antigen presenting cells (APC) and with the T cell …
-
Use of an Animal Model of Group A Streptococcal Infection to Identify Factors Important for Virulence
… necrotizing fasciitis (flesh eating disease) and streptococcal toxic shock syndrome (STSS). Virulence of the GAS is multifactorial, as it possesses an array of virulence factors regulated in a coordinated fashion by a complement of transcriptional regulators. A mouse model of streptococcal …
Page 1 of 4