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P Fimbriae
P fimbriae (also known as pyelonephritis-associated pili) or P pili or Pap are chaperon-usher type (specifically of the π family) fimbrial appendages found on the surface of many ''Escherichia coli'' bacteria. The P fimbriae is considered to be one of the most important virulence factor in uropathogenic ''E. coli'' and plays an important role in upper urinary tract infections. P fimbriae mediate adherence to host cells, a key event in the pathogenesis of urinary tract infections. Structure and expression P fimbriae are large, linear structures projecting from the surface of the bacterial cell. With lengths of 1-2um, the pili can be larger than the diameter of the bacteria itself. The main body of the fimbriae is composed of approx. 1000 copies of the major fimbrial subunit protein PapA, forming a helical rod. The short fimbrial tip is made of the subunits PapK, PapE, PapF and the tip adhesin PapG, which mediates the binding. The fimbriae is assembled by a chaperone-usher syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaperone-Usher Fimbriae
Chaperone-usher fimbriae (CU) are linear, unbranching, outer-membrane pili secreted by gram-negative bacteria through the chaperone-usher system rather than through type IV secretion or extracellular nucleation systems. These fimbriae are built up out of modular pilus subunits, which are transported into the periplasm in a Sec dependent manner. Chaperone-usher secreted fimbriae are important pathogenicity factors facilitating host colonisation, localisation and biofilm formation in clinically important species such as uropathogenic ''Escherichia coli'' and ''Pseudomonas aeruginosa''. Structure Overall All chaperone/usher systems are found within gene clusters consisting of at least an usher, a chaperone and one or more fimbriae subunits. Overall the system includes periplasmic chaperones, periplasmic and extracellular pilus subunits, dimeric usher outer membrane pore and associated Sec machinery. The Pilus subunits polymerise via a non-covalent interaction to form the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycolipid
Glycolipids are lipids with a carbohydrate attached by a glycosidic (covalent) bond. Their role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connections that allow cells to connect to one another to form tissues. Glycolipids are found on the surface of all eukaryotic cell membranes, where they extend from the phospholipid bilayer into the extracellular environment. Structure The essential feature of a glycolipid is the presence of a monosaccharide or oligosaccharide bound to a lipid moiety. The most common lipids in cellular membranes are glycerolipids and sphingolipids, which have glycerol or a sphingosine backbones, respectively. Fatty acids are connected to this backbone, so that the lipid as a whole has a polar head and a non-polar tail. The lipid bilayer of the cell membrane consists of two layers of lipids, with the inner and outer surfaces of the membrane made up of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asymptomatic Bacteriuria
Bacteriuria is the presence of bacteria in urine. Bacteriuria accompanied by symptoms is a urinary tract infection while that without is known as asymptomatic bacteriuria. Diagnosis is by urinalysis or urine culture. ''Escherichia coli'' is the most common bacterium found. People without symptoms should generally not be tested for the condition. Differential diagnosis include contamination. If symptoms are present treatment is generally with antibiotics. Bacteriuria without symptoms generally does not require treatment. Exceptions may include pregnant women, those who have had a recent kidney transplant, young children with significant vesicoureteral reflux, and those undergoing surgery of the urinary tract. Bacteriuria without symptoms is present in about 3% of otherwise healthy middle aged women. In nursing homes rates are as high as 50% among women and 40% in men. In those with a long term indwelling urinary catheter rates are 100%. Up to 10% of women have a urinary tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cystitis
A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidney infection (pyelonephritis). Symptoms from a lower urinary tract infection include pain with urination, frequent urination, and feeling the need to urinate despite having an empty bladder. Symptoms of a kidney infection include fever and flank pain usually in addition to the symptoms of a lower UTI. Rarely the urine may appear bloody. In the very old and the very young, symptoms may be vague or non-specific. The most common cause of infection is ''Escherichia coli'', though other bacteria or fungi may sometimes be the cause. Risk factors include female anatomy, sexual intercourse, diabetes, obesity, and family history. Although sexual intercourse is a risk factor, UTIs are not classified as sexually transmitted infections (STIs). Kidney ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forssman Antigen
The Forssman antigen is a glycolipid heterophil protein and a type of heterogenetic antigen found in certain animals like dogs, horses, cats, turtles and sheep, and enteric organisms such as pneumococci. In sheep, it is found on erythrocytes but not on tissue and organs, unlike hamsters and guinea pigs whose organ cells do carry the antigen. The Forssman antigen is distinct from the Paul-Bunnell antigen, antibodies to which are diagnostic of glandular fever (infectious mononucleosis Infectious mononucleosis (IM, mono), also known as glandular fever, is an infection usually caused by the Epstein–Barr virus (EBV). Most people are infected by the virus as children, when the disease produces few or no symptoms. In young adult ...). Both antigens are present on the red blood cells of horse and sheep but guinea pig kidney cells have only the Forssman antigen. A serum positive for glandular fever therefore agglutinates horse or sheep red blood cells after absorption with guinea pig k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urosepsis
Pyelonephritis is inflammation of the kidney, typically due to a bacterial infection. Symptoms most often include fever and flank tenderness. Other symptoms may include nausea, burning with urination, and frequent urination. Complications may include pus around the kidney, sepsis, or kidney failure. It is typically due to a bacterial infection, most commonly ''Escherichia coli''. Risk factors include sexual intercourse, prior urinary tract infections, diabetes, structural problems of the urinary tract, and spermicide use. The mechanism of infection is usually spread up the urinary tract. Less often infection occurs through the bloodstream. Diagnosis is typically based on symptoms and supported by urinalysis. If there is no improvement with treatment, medical imaging may be recommended. Pyelonephritis may be preventable by urination after sex and drinking sufficient fluids. Once present it is generally treated with antibiotics, such as ciprofloxacin or ceftriaxone. Those wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
