Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0034186 (pyelonephritis)
 6,144 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two new strains of Serratia marcescens were constructed by the gene manipulation method from the clinical isolate US 46, which has two kinds of pili--mannose-sensitive (MS) and mannose-resistant (MR) ones--on the cell surface. After cloning the genes of the MS and MR pili, either the MS or the MR gene was transferred to the nonpiliated Escherichia coli, and MS- or MR-piliated strains were obtained. In the experimental pyelonephritis model of rats, MS- or MR-piliated bacteria were inoculated directly to the renal parenchyma, and the following results were obtained. MS-piliated rather than MR-piliated strains stimulated severe scarring of the kidney, and this scarring was suppressed by treatment with colchicine or superoxide dismutase (SOD) during an early stage of the infection. These findings suggest that MS-piliated bacteria stimulated polymorphonuclear leukocytes, which released large amounts of superoxide resulting in renal scarring. SOD was hoped to be a drug capable of preventing renal scarring, and such a result was successfully obtained.
 ...
PMID:Suitability of colchicine and superoxide dismutase for the suppression of renal scarring following an infection with bacteria showing mannose-sensitive pili. 168 29

Renal scars are thought to be the end stage of chronic pyelonephritis and one of the most important causes of renal insufficiency and renal hypertension. The role of bacterial pili was examined in scar formation after an infection of newly constructed bacterial strains using the recombinant DNA technique, which possessed either mannose resistant (MR) or mannose sensitive (MS) pili of Serratia marcescens. Strains that differed in only a single virulence factor, namely, MR or MS pili, were used in a rat model of chronic pyelonephritis. In this model, MS-piliated bacteria stimulated renal scarring more severely than non-piliated or MR-piliated bacteria.
 ...
PMID:Increased renal scarring by bacteria with mannose-sensitive pili. 197 56

Proteus mirabilis, a common cause of urinary tract infection, can lead to serious complications including pyelonephritis. Adherence factors, urease, and hemolysin may be virulence determinants. These factors were compared for bacteria cultured from 16 patients with acute pyelonephritis and 35 with catheter-associated bacteriuria and for 20 fecal isolates. Pyelonephritis isolates were more likely (P less than .05) to express the mannose-resistant/Proteus-like (MR/P) hemagglutinin in the absence of mannose-resistant/Klebsiella-like (MR/K) hemagglutinin than were catheter-associated or fecal isolates. Pyelonephritis isolates produced urease activity of 63 +/- 27 (mean +/- SD) mumol of NH3/min/mg of protein, not significantly different from catheter-associated or fecal isolates. Hybridization of Southern blots of P. mirabilis chromosomal DNA with two urease gene probes demonstrated that urease gene sequences were conserved in all isolates. Geometric mean of reciprocal hemolytic titers for pyelonephritis isolates was 27.9; for urinary catheter isolates, 18.0; and for fecal isolates, 55.7 (not significantly different, P greater than .1). Although in vivo expression of urease and hemolysin may not be reliable indexes of virulence, MR/P hemagglutination in the absence of MR/K hemagglutination may be necessary for development of pyelonephritis.
 ...
PMID:Hemagglutinin, urease, and hemolysin production by Proteus mirabilis from clinical sources. 217 24

Acute pyelonephritis, a complication of Escherichia coli bacteriuria, must represent a bacterial invasion through the kidney epithelium. To study this process, we overlaid bacterial suspensions onto monolayers of cultured human kidney proximal tubular epithelial cells and measured cytotoxicity by release of lactate dehydrogenase (LDH). Thirty-four isolates cultured from patients with acute pyelonephritis were screened for the ability to cause pyelonephritis in CBA mice by transurethral challenge. The eight most virulent strains (greater than or equal to 70% of mice challenged developed greater than or equal to 10(3) CFU/g of kidney after 48 h) were selected for study. Each strain displayed mannose-resistant hemagglutination of human O erythrocytes; three strains were phenotypically and genotypically hemolytic. Pyelonephritogenic strains were significantly more cytotoxic (30.1 +/- 9.5% LDH release after 18 h) than eight fecal control strains (13.5 +/- 11.5% LDH release; P = 0.0068). We selected the most cytotoxic strain, CFT073, for further study. Sterile filtrate from this hemolytic strain was significantly more cytotoxic than was the filtrate of the fecal control strain, FN414. Transposon mutagenesis of CFT073 with TnphoA abolished hemolytic activity and cytotoxicity by both whole cells and sterile filtrate. Southern blot analysis revealed that the Tnphoa insertion mapped to the E. coli chromosomal hly determinant within a 12-kilobase SalI restriction fragment. Transformation of a nonhemolytic strain, CPZ005 with plasmid pSF4000, which carries a cloned hemolysin determinant, resulted in highly elevated cytotoxicity. Light micrographs of proximal tubular epithelial cell cultures demonstrated cell damage by pyelonephritogenic strains that was not induced by a fecal strain or the hemolysin-deficient mutant. Results indicate that pyelonephritogenic E. coli strains are more frequently cytotoxic for a putative target, that is, human renal tubular epithelium, than are fecal isolates. Hemolysin, in some strains, is apparently responsible for this cytotoxicity.
 ...
PMID:Pyelonephritogenic Escherichia coli and killing of cultured human renal proximal tubular epithelial cells: role of hemolysin in some strains. 218 40

Cell surface hydrophobicity, haemagglutination pattern and adherence to HeLa cells were examined in 230 strains of Escherichia coli collected from women (n = 61 strains) and children (n = 65 strains) with non-obstructive acute pyelonephritis and in 104 faecal control strains of E. coli from healthy adults (n = 71 strains) and children (n = 33 strains). Pyelonephritogenic E. coli strains showed a significantly increased incidence of hydrophobic properties (90%) and mannose resistant haemagglutination (MRHA) of human erythrocytes (83%) than faecal control strains (64 and 23% respectively, P less than 0.001 in both cases). Mannose sensitive haemagglutination (MSHA) was observed in 48% of the pyelonephritogenic E. coli strains and in 50% of the faecal control strains (NS). The incidence of adherence to HeLa cells was low both in pyelonephritogenic and faecal control strains, 6 and 7% respectively (NS). The bacterial phenotypes MRHA + MSHA + and MRHA + MSHA- appeared significantly more often in pyelonephritogenic E. coli strains (35 and 48% respectively) than in faecal control strains (5 and 17% respectively, P less than 0.001 in both cases). The phenotype MRHA- MSHA + occurred significantly more often in control strains (45%) than in pyelonephritogenic strains (13%, P less than 0.001). Eighty-three per cent of the pyelonephritogenic E. coli strains expressing hydrophobic properties showed MRHA and 50% of the hydrophobic strains showed MSHA. There were no significant correlations between cell surface hydrophobic properties and haemagglutination pattern or adherence to HeLa cells in pyelonephritogenic E. coli strains nor in faecal control strains.
 ...
PMID:Cell surface hydrophobicity, adherence to HeLa cell cultures and haemagglutination pattern of pyelonephritogenic Escherichia coli strains. 220 32

Two hundred and thirty-two strains of Escherichia coli isolated from children with non-obstructive acute pyelonephritis (n = 65), women with non-obstructive acute pyelonephritis (n = 63) and the faecal flora of healthy children (n = 33) and adults (n = 71) were examined for cytotoxic necrotizing factor production, haemolysin synthesis, verocytotoxin production and expression of mannose-resistant haemaglutination of human erythrocytes. Forty-eight per cent of the pyelonephritogenic Escherichia coli strains produced cytotoxic necrotizing factor and 61% produced haemolysin compared to 25% and 27% of faecal control strains (p less than 0.001 and p less than 0.001 respectively). Cytotoxic necrotizing factor production did not occur among the non-haemolytic Escherichia coli strains which confirms the close association between these two toxic factors. The bacterial phenotypes producing both haemolysin and cytotoxic necrotizing factor, and the phenotype expressing both these toxic factors and mannose-resistant haemagglutination occurred significantly more often in pyelonephritogenic strains than in faecal isolates (p less than 0.001). Haemolytic strains without the ability to produce cytotoxic necrotizing factor were more common in faecal isolates than in uropathogenic strains (p = 0.05). Strains lacking the ability to synthesize both these toxins were also over-represented in faecal isolates (p less than 0.01).
 ...
PMID:Production of cytotoxic necrotizing factor, verocytotoxin and haemolysin by pyelonephritogenic Escherichia coli. 226 21

We examined the frequency of bacterial strains expressing cell surface hydrophobicity, P-fimbriae, mannose-resistant haemagglutination (MRHA), type I fimbriae, production of aerobactin, haemolysin synthesis (Hly), production of cytotoxic necrotising factor (CNF) and HeLa cell adherence in 126 strains of Escherichia coli isolated from children (n = 65) and women (n = 61) with acute non-obstructive pyelonephritis. Previous investigations have shown that pyelonephritogenic strains of E. coli more often express hydrophobic properties, P-fimbriae, MRHA, aerobactin-mediated iron uptake, Hly and CNF production than strains isolated from the faecal flora of healthy persons. The objective of the present study was to examine phenotypic differences between strains of E. coli obtained from children with their first episode of acute pyelonephritis and strains from women with non-obstructive acute pyelonephritis. Of the pyelonephritogenic strains of E. coli isolated from children, 98% expressed cell surface hydrophobic properties compared to 82% isolated from adults (P = 0.004). Strains from children and adults had the same ability to assimilate iron and equally often expressed P-fimbriae, MRHA and type I fimbriae. Strains from children with acute pyelonephritis more significantly expressed Hly (72%) and CNF (58%) than did pyelonephritogenic strains from adults (49 and 37% respectively, P = 0.013 and P = 0.028 respectively). The frequency of HeLa cell adherence was similar and low in both groups. The phenotype aerobactin+ Hly+ and Hly+CNF+ was found significantly more often in pyelonephritogenic strains from children than in strains from adults (P = 0.006 and P = 0.028 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Phenotypic differences and characteristics of pyelonephritogenic strains of Escherichia coli isolated from children and adults. 227 74

Escherichia coli (E. coli) causes greater than 90% of urinary tract infections, UTI, in childhood. The capacity to adhere to urinary tract epithelial cells characterizes E. coli strains that cause acute pyelonephritis. Adherence of uropathogenic E. coli is the result of a specific interaction between bacterial adhesins and glycolipid receptors on the host cells, especially the globoseries of glycolipids which share the Galactose alpha 1-greater than 4Galactose beta disaccharide (Gal alpha 1-greater than 4Gal beta). In childhood UTI, Gal alpha 1-greater than 4Gal beta-binding bacteria caused significantly higher body temperature, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and pyuria, and lower renal concentrating capacity, than E. coli lacking this specificity. The Gal alpha 1-greater than 4Gal beta-binding bacteria thus appeared to be more potent inducers of inflammation than other strains. Since inflammation may lead to tissue damage we examined the relationship of infection with Gal alpha 1-greater than 4Gal beta-positive bacteria to renal scarring. The frequency of renal scarring was 5% in boys with Gal alpha 1-greater than 4Gal beta-positive and 40% in boys with Gal alpha 1-greater than 4Gal beta-negative E. coli. Bacterial binding to Gal alpha 1-greater than 4Gal beta can be detected with a commercially available test reagent. This reagent can thus be used as an effective predictor of risk for renal scarring. Interleukin-6 (IL-6) is a pyrogen and inducer of the acute phase reactants. It was shown to be produced locally in the urinary tract, in response to UTI, and to spread systemically. Mucosal challenge with dead bacteria was sufficient to induce the IL-6 response. Circulating IL-6, and/or IL-1 and tumor necrosis factor could explain the fever, as well as increased ESR and CRP found in association with acute symptomatic UTI.
 ...
PMID:Bacterial adherence as a virulence factor in urinary tract infection. 228 1

The antibody response to P-fimbriae of Escherichia coli in patients with upper urinary tract infections was investigated. In the sera of patients with pyelonephritis obtained at the initial visit to hospital (3 to 7 days after the onset of symptoms), a high incidence of antibodies to P-fimbriae was detected (12 out of 14 patients). P-fimbriated Escherichia coli strains were isolated from urine samples in all of these antibody-positive patients. Antibodies detected by ELISA using purified antigen were essentially IgG and specifically recognized P-fimbriae. These antibodies inhibited completely, or in some cases partially, mannose-resistant hemagglutination with P-fimbriated Escherichia coli.
 ...
PMID:Serological response to P-fimbriae of Escherichia coli in patients with urinary tract infections. 256 83

The uptake of D-glucose, L-aspartate, L-lysine and L-proline was investigated in renal brush border membrane (BBM) vesicles prepared from control, infected or passively-immunized-infected rats. Except L-aspartate, a progressive decrease in the uptake of these nutrients in both infected and immunized-infected groups during the course of infection was observed, but the changes were less apparent in immunized-infected rats than in non-immunized ones. The uptake of L-aspartate was increased in vesicles from early stages of infection but decreased in those from later stages. Also in L-aspartate uptake, the changes were smaller in immunized animals. The uptake of nutrients was detectable earlier than were histopathological alterations of both kidneys. The observations demonstrated that uptake of D-glucose and amino acids in the kidneys is disturbed prior to appearance of histopathological lesions and thus can be used for early detection of the disease. The data also demonstrate that antipili antibodies afford partial protection against ascending pyelonephritis.
 ...
PMID:Transport of nutrients into the renal brush border membrane vesicles as marker in evaluating the role of antipili antibodies in modulation of ascending pyelonephritis in rats. 256 54


<< Previous 1 2 3 4 5 6 7 8 Next >>