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J W Warren

Publications and source records attributed to J W Warren.

At least 37 records · Page 2Linked to original sources
PubMed1998

Polymerase chain reaction amplification of bacterial 16S rRNA genes in interstitial cystitis and control patient bladder biopsies.

PURPOSE: Several characteristics of the chronic bladder disease called interstitial cystitis (IC) suggest an infectious etiology. However, a single causative organism has not been convincingly cultured in vitro, and DNA for a variety of microorganisms has been found inconsistently in bladder biopsies from IC patients. We therefore looked for a possible bacterial cause for IC by using a sensitive nested PCR assay on cystoscopic bladder biopsy specimens obtained from IC patients and controls. MATERIALS AND METHODS: Bladder biopsies were obtained at cystoscopy from 6 IC patients and 6 controls. DNA was extracted from these specimens and PCR with 2-round amplification performed using nested primers from a highly conserved region of the bacterial 16s rRNA gene. Amplified DNA was purified and sequenced using the Sequenase PCR Product Sequencing Kit, and the sequences obtained were compared with bacterial rRNA gene sequences recorded in GenBank. RESULTS: Biopsy specimens from all 6 patients and 6 controls were positive by PCR for DNA encoding bacterial 16s rRNA. Sequence data indicated a predominant microorganism in 10 of the 12 specimens, with > 95% homology to DNA from several different genera of bacteria including Acinetobacter, Propionobacterium, Salmonella, and Escherichia. None of the organisms identified by PCR had been cultured from tissue or urine obtained simultaneously from these persons, using sensitive culture techniques. CONCLUSIONS: These data indicate no difference between IC patients and controls in the proportion of bladder biopsies with PCR positivity or the type(s) of organism present, providing additional evidence that IC is not associated with infection by a particular type of bacterium.

Cystitis, Interstitial↗
PubMed1998

A diagnostic in vitro urine assay for interstitial cystitis.

OBJECTIVES: A low molecular weight urine factor that inhibits the proliferation of normal bladder epithelial cells in vitro was previously shown to be present significantly more often in the urine of patients with interstitial cystitis (IC) than in the urine of asymptomatic age-, race-, and sex-matched control subjects. We sought to determine the specificity of this finding for IC by determining whether the urine of patients with other urogenital inflammatory disorders also contains a factor that inhibits bladder epithelial cell proliferation. METHODS: Urine was collected from women with IC, acute bacterial cystitis, or vulvovaginitis, as well as from asymptomatic control women. The proliferation of primary normal adult bladder epithelial cells was determined by measuring 3H-thymidine incorporation in vitro. RESULTS: Osmolality- and pH-corrected urine specimens from 50 (86%) of 58 women with IC significantly inhibited human bladder epithelial cell proliferation compared with 3 (8%) of 36 asymptomatic control women, 7 (12%) of 58 women with bacterial cystitis, and 0 (0%) of 12 women with vulvovaginitis (P < 0.001 for the comparison of mean percent change in 3H-thymidine incorporation with IC urine versus urine from each of the control groups). Optimal sensitivity and specificity values of 91.4% and 90.6%, respectively, were achievable at a cutoff of 25% inhibition of 3H-thymidine incorporation, using all three control groups. CONCLUSIONS: The measurement of urine antiproliferative activity may be a useful noninvasive means for diagnosing IC in women.

Adult↗
PubMed1998

A hypothesis for the etiology of interstitial cystitis based upon inhibition of bladder epithelial repair.

Interstitial cystitis (IC) is a chronic bladder disease characterized by distinct bladder mucosal abnormalities, for which the etiology is unknown. Although the epidemiology of this disorder is similar to that of bacterial cystitis, prospective studies using sensitive culture techniques and polymerase chain reaction assay for a variety of microorganisms have failed to identify a specific infectious etiology for IC. We have identified a low-molecular-weight peptide in the urine of IC patients that inhibits the proliferation of normal bladder epithelial cells in vitro. We therefore propose a model of IC, in which this peptide inhibits bladder epithelial regeneration following damage (such as that caused by bacterial cystitis). The chronically damaged epithelium is prone to colonization with various microorganisms, and the resulting exposure to these microorganisms, other urinary antigens, and/or damaged epithelial cells prompts the low-level inflammatory response commonly seen in this disorder.

Cystitis, Interstitial↗
PubMed1998

Polymerase chain reaction amplification of bacterial 16S rRNA genes from cold-cup biopsy forceps.

PURPOSE: In looking for a possible infectious cause for interstitial cystitis (IC), we previously determined that bladder tissue specimens from both IC patients and controls were uniformly positive by polymerase chain reaction assay (PCR) for bacterial 16S ribosomal RNA genes from various genera including Escherichia, Propionobacterium, Acinetobacter, and Salmonella. We therefore determined whether the biopsy forceps might be contaminated with bacterial DNA. MATERIALS AND METHODS: A total of 23 samples were obtained following disinfection of 6 cold-cup bladder biopsy forceps (2 to 5 specimens from each forceps over a period of 19 months). DNA was extracted from each sample, and PCR performed using nested primers from a highly conserved region of the bacterial 16S rRNA gene. Amplified DNA was purified and sequenced, and the sequences obtained were compared with bacterial rRNA gene sequences recorded in GenBank. RESULTS: Thirteen of 23 forceps specimens were positive by PCR for bacterial DNA, including at least one rinse from each of the 6 forceps. In comparison, none of 9 negative control specimens (sterile distilled water put into tubes and processed in the same manner as forceps rinses) had detectable bacterial DNA. Sequence data indicated the presence of a predominant organism in 12 of the 13 positive specimens, with >95% homology to DNA from several different genera of bacteria including Escherichia, Propionobacterium, Stenotrophomonas and Pseudomonas. CONCLUSIONS: These data indicate that reusable bladder biopsy forceps are frequently contaminated with bacterial DNA. Tissue specimens procured with such instruments therefore are inappropriate sources to look for the presence of bacterial pathogens by PCR.

Biopsy↗
PubMed1998

Comparison of Escherichia coli strains recovered from human cystitis and pyelonephritis infections in transurethrally challenged mice.

Urinary tract infection, most frequently caused by Escherichia coli, is one of the most common bacterial infections in humans. A vast amount of literature regarding the mechanisms through which E. coli induces pyelonephritis has accumulated. Although cystitis accounts for 95% of visits to physicians for symptoms of urinary tract infections, few in vivo studies have investigated possible differences between E. coli recovered from patients with clinical symptoms of cystitis and that from patients with symptoms of pyelonephritis. Epidemiological studies indicate that cystitis-associated strains appear to differ from pyelonephritis-associated strains in elaboration of some putative virulence factors. With transurethrally challenged mice we studied possible differences using three each of the most virulent pyelonephritis and cystitis E. coli strains in our collection. The results indicate that cystitis strains colonize the bladder more rapidly than do pyelonephritis strains, while the rates of kidney colonization are similar. Cystitis strains colonize the bladder in higher numbers, induce more pronounced histologic changes in the bladder, and are more rapidly eliminated from the mouse urinary tract than pyelonephritis strains. These results provide evidence that cystitis strains differ from pyelonephritis strains in this model, that this model is useful for the study of the uropathogenicity of cystitis strains, and that it would be unwise to use pyelonephritis strains to study putative virulence factors important in the development of cystitis.

Animals↗
PubMed1998

Cytotoxicity of hemolytic, cytotoxic necrotizing factor 1-positive and -negative Escherichia coli to human T24 bladder cells.

Approximately one-half of Escherichia coli isolates from patients with cystitis or pyelonephritis produce the pore-forming cytotoxin hemolysin, a molecule with the capacity to lyse erythrocytes and a range of nucleated cell types. A second toxin, cytotoxic necrotizing factor 1 (CNF1), is found in approximately 70% of hemolytic, but rarely in nonhemolytic, isolates. To evaluate the potential interplay of these two toxins, we used epidemiological and molecular biologic techniques to compare the cytotoxicity of hemolytic, CNF1(+), and CNF1(-) cystitis strains toward human T24 bladder epithelial cells in vitro. A total of 29 isolates from two collections of cystitis-associated E. coli were evaluated by using methylene blue staining of bladder monolayers at 1-h intervals after inoculation with each strain. Most (20 of 29) isolates damaged or destroyed the T24 monolayer (less than 50% remaining) within 4 h after inoculation. As a group, CNF1(+) isolates from one collection (11 strains) were less cytotoxic at 4 h than the CNF1(-) strains in that collection (P = 0.009), but this pattern was not observed among isolates from the second collection (18 strains). To directly evaluate the role of CNF1 in cytotoxicity of hemolytic E. coli without the variables present in multiple clinical isolates, we constructed mutants defective in production of CNF1. Compared to the CNF1(+) parental isolates, no change in cytotoxicity was detected in these cnf1 mutants. Our results indicate that CNF1 does not have a detectable effect on the ability of hemolytic E. coli to damage human bladder cell monolayers in vitro.

Bacterial Toxins↗
PubMed1997

Concentrations of specific epithelial growth factors in the urine of interstitial cystitis patients and controls.

PURPOSE: Interstitial cystitis (IC) is a chronic bladder disease for which the etiology is unknown. Because the bladder epithelium is often abnormal in IC, we determined whether the levels of specific urine growth factors postulated to be important for bladder epithelial proliferation are altered in IC. MATERIALS AND METHODS: ELISAs were used to determine levels of epidermal growth factor (EGF), insulin-like growth factor 1 (IGF1), insulin-like growth factor binding protein 3 (IGFBP3), and heparin binding epidermal growth factor-like growth factor (HB-EGF) in urine specimens from women with IC, asymptomatic women without bladder disease, and women with bacterial cystitis. RESULTS: Urine HB-EGF levels were specifically and significantly decreased in IC patients as compared to asymptomatic controls or patients with bacterial cystitis, whether expressed as concentration (amount per volume of urine) or the amount relative to urine creatinine in each specimen. In contrast, urine EGF, IGF1, and IGFBP3 levels were all significantly elevated in IC patients compared to asymptomatic controls. Further, the amounts of urine EGF and IGF1 were also elevated in IC patients as compared to patients with bacterial cystitis, and urine IGFBP3 levels were significantly elevated when expressed per milligram of urine creatinine. CONCLUSIONS: These findings indicate that complex changes in the levels of urine epithelial cell growth factors (EGF, IGF1, and HB-EGF) and a growth factor binding protein (IGFBP3) are associated with IC. While EGF, IGF1, and IGFBP3 levels are either the same or increased in the urine of IC patients as compared to patients with bacterial cystitis or asymptomatic controls, HB-EGF levels are significantly decreased in the urine of IC patients. Understanding the reasons for these changes may lead to understanding the pathogenesis of this disorder.

Adult↗
PubMed1997

Catheter-associated urinary tract infections.

Millions of urethral catheters are used each year. This device subverts several host defenses to allow bacterial entry at the rate of 3% to 10% incidence per day, and its presence encourages the organism's persistent residence in the urinary tract. Most catheter-associated bacteriurias are asymptomatic. The complications in short-term catheterized patients include fever, acute pyelonephritis, bacteremia, and death; patients with long-term catheters in place are at risk for these complications and catheter obstruction, urinary tract stones, local periurinary infections, chronic renal inflammation, chronic pyelonephritis, and, over years, bladder cancer. The closed catheter system has been a magnificant step forward in the prevention of catheter-associated bacteriuria. Indeed, only two catheter principles are universally recommended: keep the closed catheter system closed and remove the catheter as soon as possible. Most modifications of the closed catheter system have not improved markedly on its ability to postpone bacteriuria. On first inspection, systemic antibiotics seem to be an exception to this rule, but their use results in infection of the bladder with resistant organisms, including candida. This and the effect of side effects on the patient and emergence of resistant bacteria in the medical unit have led most authorities to conclude that antibiotics are not useful for prevention of bacteriuria, nor for treatment of bacteriuria in the asymptomatic catheterized patient. For symptomatic patients, usually with fever or signs of sepsis, treatment of bacteriuria with appropriate systemic antibiotics and removal or replacement of the urethral catheter are indicated. Gloves, hand washing, and segregation of catheterized patients can minimize nosocomial clusters. Because clinicians can only postpone bacteriuria, and once it occurs, clinicians seem unable to prevent its complications, methodologies other than urethral catheters should be used for urine drainage assistance whenever possible. These options include condom, intermittent, suprapubic, and intraurethral catheterization for appropriate patients. The few data available suggest that each one of these catheterization options yields a lower incidence of bacteriuria-and its consequent complications-than urethral catheterization.

Aged↗
PubMed1997

Proxies' decisions about clinical research participation for their charges.

OBJECTIVE: To examine the process by which proxies decide about their charges' participation in clinical research. DESIGN: Using eight hypothetical research studies encompassing a variety of risks and benefits, we interviewed 315 competent persons > or = 65 years old (charges) and, separately, the individuals who would be designated as their proxies if the charges were to become incompetent. The proxies were asked what they thought their charges would decide and what decisions they would make for their charges and for their own participation. SETTINGS: A medical house-call program, two apartment complexes, and three nursing homes. PARTICIPANTS: Charges > or = 65 years old and their proxies. MAIN OUTCOME MEASURE: Comparison of decisions made by charges and by proxies for their charges. RESULTS: The agreement between the proxies' and charges' decisions was not significantly different from random agreement (range of kappa statistics, 0.05-0.15). Rather, proxies' decisions for their charges were significantly related to the proxies' decisions for themselves (kappas, 0.52-0.86). When the paired proxies' and charges' decisions differed, the proxies were protective, more frequently refusing their charges' participation in the perceived riskier research studies. CONCLUSIONS: Proxies did not know what their charges would decide. Their choices for the charges related more to the proxies' decisions about their own participation (which they knew) than to the decisions of their charges (which they didn't know). This is similar to the process of a reasonable person making the decision, a characteristic of decisions made in the best interests of the patient.

Adult↗
PubMed1997

Pathogenicity island sequences of pyelonephritogenic Escherichia coli CFT073 are associated with virulent uropathogenic strains.

Urinary tract infection is the most frequently diagnosed kidney and urologic disease, and Escherichia coli is by far the most common etiologic agent. Defined blocks of DNA termed pathogenicity islands have been found in uropathogenic strains to carry genes not generally found in fecal strains. We have identified one of these regions of DNA within the chromosome of the highly virulent E. coli CFT073, isolated from the blood and urine of a woman with acute pyelonephritis. This strain, which is cytotoxic for cultured renal cells and causes acute pyelonephritis in transurethrally infected CBA mice, contains two distinct copies of the pap operon and is hemolytic. One pap operon was localized on a cosmid clone which was used to identify three overlapping cosmid clones. By using restriction mapping, DNA hybridization, sequencing, and PCR amplification, a region of approximately 50 kb was found to be present in this uropathogenic strain and to have no corresponding sequences in E. coli K-12. This gene block also carries hemolysin genes hlyCABD. The pathogenicity island begins 7 bp downstream of dadX (catabolic alanine racemase; 26.55 min) and ends at a position in the K-12 genome 75 bp downstream of the metV tRNA gene (62.74 min); this suggests that a chromosomal rearrangement has occurred relative to the K-12 linkage map. The junctions of the pathogenicity island were verified by PCR amplification directly from the genomic DNA of strain CFT073. DNA sequencing within the boundaries of the junctions revealed genes not previously identified in E. coli or in some cases bearing no known homologs. When used as probes for DNA hybridization, these sequences were found significantly more often in strains associated with the clinical syndromes of cystitis (82%) and acute pyelonephritis (79%) than in fecal strains (19%; P < 0.001).

Adult↗
PubMed1997

Urine autoantibodies in interstitial cystitis.

Interstitial cystitis is a chronic bladder disease with certain features that suggest autoimmunity may play a role in initiating or maintaining the disease process. We therefore determined whether immunoglobulin fractions from 14 IC patient and 19 control urine specimens bound in vitro to primary cultures of human bladder epithelial cells, as well as epithelial cells from a variety of other tissues. Urine autoantibodies that bound to normal human bladder epithelial cells were present in 8 of 14 IC specimens (from 6 of 9 IC patients) as compared to 3 of 23 control specimens (from 2 of 17 control patients). These antibodies, which were usually also present at low titers in sera from these persons, bound to at least four nuclear or cytoplasmic antigens, with the specificity of autoantibodies from a given individual varying over time. The autoantibodies were not specific for normal or malignant bladder epithelial cells, but bound to epithelial cells from a variety of tissues. These data show that anti-epithelial cell autoantibodies are present in the urine of IC patients, but suggest that these antibodies are not likely to be a primary cause of this disease.

Adult↗
PubMed1996

Construction of a flagellum-negative mutant of Proteus mirabilis: effect on internalization by human renal epithelial cells and virulence in a mouse model of ascending urinary tract infection.

To examine the role of flagella in pathogenesis of urinary tract infection caused by Proteus mirabilis, we constructed a nonmotile, nonswarming flagellum mutant of strain WPM111 (an hpmA hemolysin mutant of strain BA6163, chosen because of its lack of in vitro cytotoxicity in renal epithelial cell internalization studies). A nonpolar mutation was introduced into the flaD gene, which encodes the flagellar cap protein. This mutation does not affect the synthesis of flagellin but rather prevents the assembly of an intact flagellar filament. In in vitro assays, the genetically characterized nonmotile mutant was found to be internalized by cultured human renal proximal tubular epithelial cells in numbers less than 1% of those of the flagellated parent strain. Internalization of the nonmotile mutant was increased significantly (14- to 21-fold) by centrifugation onto the monolayer. To assess virulence in vivo, CBA mice were challenged transurethrally with 10(7) CFU of P. mirabilis BA6163 (wild type) (n = 16), WPM111 (hpmA mutant) (n = 46), or BB2401 (hmpA flaD mutant) (n = 46). Differences in quantitative cultures between the parent strain and the hemolysin-negative mutant were not significant. However, the hpmA flaD mutant was recovered in numbers approximately 100-fold lower than those of the hmpA mutant or the wild-type parent strain and thus was clearly attenuated. We conclude that while hemolysin does not significantly influence virulence, flagella contribute significantly to the ability of P. mirabilis to colonize the urinary tract and cause acute pyelonephritis in an experimental model of ascending urinary tract infection.

Animals↗
PubMed1996

Decreased 3H-thymidine incorporation by human bladder epithelial cells following exposure to urine from interstitial cystitis patients.

PURPOSE: Interstitial cystitis (IC) is a chronic bladder disease of unknown etiology. We sought to determine whether a cytotoxin is present in the urine of IC patients that could cause the epithelial damage seen in this disease. MATERIALS AND METHODS: Evidence for a cytotoxin was sought using both a neutral red uptake viability assay in T24 bladder epithelial cells, and a 3H-thymidine incorporation assay in primary normal adult bladder epithelial cells and FHS 738 Bl human fetal bladder cells. RESULTS: The neutral red assay in T24 cells indicated the presence of a cytotoxin in 2 of 9 IC patient urine specimens. However, the more sensitive assay of cell proliferation (3H-thymidine incorporation) in normal adult human bladder epithelial cells revealed antiproliferative activity in urine from 10 of 13 (77%) IC patients vs. 3 of 19 (16%) controls (two-way analysis of variance, p = .019). The antiproliferative activity of IC urine specimens was confirmed using FHS 738 Bl human fetal bladder cells. The antiproliferative urinary substance(s) appeared to be a low molecular weight (< 10,000 Da), heat stable, trypsin-sensitive factor(s). CONCLUSIONS: Because a denuded or damaged bladder epithelium is a central finding in IC, it is possible that the antiproliferative protein(s) contributes to the pathogenesis of this disease.

Adult↗
PubMed1995

Spatial features in body-surface potential maps can identify patients with a history of sustained ventricular tachycardia.

BACKGROUND: Regional disparities of ventricular primary-repolarization properties contribute to an electrophysiological substrate for arrhythmias. Such disparities can be assessed from body-surface distributions of ECG QRST areas. Our objective was to isolate and test those features of QRST-area distributions that would be suitable for identifying patients at risk for life-threatening ventricular arrhythmias. METHODS AND RESULTS: We recorded ECGs simultaneously from 120 leads during sinus rhythm for 204 patients taking no antiarrhythmic drugs: half had had sustained ventricular tachycardia (VT); the other half, a myocardial infarction but no history of VT. For each patient, we calculated the QRST area in each lead and, using Karhunen-Loeve (K-L) expansion, reduced these data to 16 coefficients (each relating to one spatial feature, an eigenvector, derived from the total set of 204 QRST-area maps). Using stepwise discriminant analysis, we selected feature subsets that best discriminated between the two groups, and we estimated by a bootstrap procedure using 1000 trials how these subsets would perform on a prospective patient population. The mean diagnostic performance of the classifier for 1000 randomly selected training sets (n = 102 in each, with both groups equally represented) increased monotonically with the number of features used for classification. The initial trend for the corresponding test sets (n = 102 in each) was the same but reversed when the number of features exceeded eight. For an optimal set of eight spatial features, the sensitivity and specificity of the classifier for detecting patients with VT in 1000 test sets were (mean +/- SD) 90.3 +/- 4.3% and 78.0 +/- 6.1%, and its positive and negative predictive accuracies were 80.7 +/- 4.2% and 89.2 +/- 4.2%, respectively. Use of QRS duration as a supplementary feature to eight K-L coefficients can, in the test sets, increase specificity to 80.9 +/- 5.4% and positive predictive accuracy to 82.8 +/- 3.9% compared with the results for the optimal number of eight K-L features alone. CONCLUSIONS: Multiple body-surface ECGs contain valuable spatial features that can identify the presence of an arrhythmogenic substrate in the myocardium of patients at risk for ventricular arrhythmias. Our results compare very favorably with those achieved by any other known test, invasive or noninvasive, for arrhythmogenicity.

Body Surface Potential Mapping↗
PubMed1995

A prospective study of microorganisms in urine and bladder biopsies from interstitial cystitis patients and controls.

OBJECTIVES: Interstitial cystitis (IC) is a chronic inflammatory condition of the bladder of unknown etiology. We tested the hypothesis that a microorganism would be found at higher prevalence in urine or bladder tissue from women with IC than from control women. METHODS: Urine and bladder tissue were obtained at cystoscopy from 11 IC patients and 7 control subjects. These specimens were cultured for a variety of fastidious and nonfastidious bacteria, mycobacteria, fungi, and viruses. In addition, special staining techniques were used to examine biopsy specimens and cytospun urine, and tissue sections and outgrowths of explanted bladder cells were examined by electron microscopy. RESULTS: Cultures of urine from 6 of 11 IC patients grew five different bacteria (Corynebacterium sp. Klebsiella pneumoniae, Lactobacillus sp, Streptococcus constellatus, and Streptococcus morbillorum), human cytomegalovirus, or Torulopsis glabrata; one of these organisms (Lactobacillus sp) was found in urine from 2 patients. Although contamination by urethral organisms is possible, the prevalence of microorganisms in urine of IC patients (6 of 11) was significantly greater than in urine of control subjects (0 of 7) (P < 0.05). Acridine orange staining revealed rods with appropriate morphology in urine from 4 of the 5 IC patients who had positive bacterial cultures and yeastlike organisms in urine and bladder tissue specimens that grew Torulopsis. Additionally, rodlike organisms were seen in urine from 2 IC patients with negative bacterial cultures and cocci were seen in the urine of 1 control patient. Biopsy specimens from 2 IC patients grew Torulopsis sp or Lactobacillus sp, in agreement with the results of acridine orange staining and culture of urine from these patients; in contrast, specimens from 3 control subjects grew small numbers of Pseudomonas sp or Staphylococcus epidermidis, but no organisms were cultured from urine or seen in acridine orange-stained tissue smears. All other cultures and stains were negative. CONCLUSIONS: These data do not provide evidence that IC is associated with infection or colonization by a single microorganism. However, they do generate the hypothesis that the prevalence of microorganisms, especially bacteria at low concentrations, is greater in the urine of IC patients than of control subjects. If these results are confirmed by other controlled studies, the question of whether the presence of these organisms is a cause or a result of IC should be addressed.

Biopsy↗