Bacterial osmoprotection.
Explore the source record for details and available documents.
Adaptation, Physiological↗
Biomedical subjects
G J Domingue
Publications and source records attributed to G J Domingue.
Outer membrane proteins of E. coli in the host-pathogen interaction in urinary tract infection.
Outer membrane protein patterns (Omp) of Escherichia coli obtained directly from the urine of bacteriuric patients without passage on artificial culture media (ACM) were studied by polyacrylamide gel electrophoresis (SDS-PAGE) in an effort to determine whether in vivo conditions of growth affected the expression of these bacterial surface structures. Seventeen strains studied showed two distinct Omp patterns: one protein band appeared at the level of porin proteins (40 kDa) in both patterns, but Omp A protein was at the level of 36 kDa in the first pattern and a new protein was observed at 21.5 kDa in the second pattern suggesting that it is a fragment of Omp A. High molecular weight proteins were also observed in most of the strains and this finding was related to lack of free iron when the same strains were grown under iron restricted conditions in vitro. The same strains grown in pooled urine from normal females showed the first pattern mentioned above. Comparative growth on ACM of urinary strains and E. coli strains isolated from blood, feces and wounds showed an increase in the number of porins expressed (from 1 to 2 or 3, with some variability observed between strains). Differences in osmolality between pooled urine and ACM used, plus in vitro studies varying the osmolality of culture media, showed that osmolality accounted for differences in the number of porins expressed: porin expression decreased in urine the ACM of high osmolality, suggesting that the same phenomena occurred in vivo. It is concluded that host factors including low availability of iron and high osmolality present in the urinary tract influence the expression of several E. coli surface proteins. These proteins may relate to the ability of E. coli to colonize and invade the urinary tract by regulating the physiologic and/or metabolic state of the bacterial cell favoring survival of the organism in a hostile environment. Specific immune responses directed against porins could influence the outcome of this host-parasite interaction.
Bacterial Outer Membrane Proteins↗
Initial antibiotic therapy for alligator bites: characterization of the oral flora of Alligator mississippiensis.
An open thumb fracture resulting from an alligator bite became infected with Aeromonas hydrophila, Enterobacter agglomerans, and Citrobacter diversus. The patient was treated by surgical debridement and antibiotic therapy. We obtained cultures from the mouth of ten alligators to characterize their oral flora. Initial empiric therapy after alligator bites should be directed at gram-negative species, in particular, Aeromonas hydrophila and anaerobic species including Clostridium. Of the numerous fungi that were isolated, none has been reported to result in wound infection after alligator bites.
Adult↗
Virulence of wild-type E. coli uroisolates in experimental pyelonephritis.
This study was designed to analyze the colonizing and invasive properties of wild-type bacteriuric E. coli possessing a variety of phenotypic characteristics in experimental nonobstructive pyelonephritis (P and Type 1 [T] fimbriae, hemolysin [Hly], presence of K capsules, flagella [H], serotype, biotype, human and mouse serumcidal resistance). Special emphasis was on the role of Gal-Gal adhesin (P fimbriae) of non-genetically engineered uroisolates. It was shown that organisms that are P+ or T+ or Hly+ are more likely to colonize bladders than strains negative for those parameters (P less than 0.001). Additionally, P+ strains were more often associated with kidney histopathology than P- E. coli (P less than 0.05). However, the data also indicated that fimbriae (P and Type 1) were not sole determinants of virulence since two strains devoid of fimbriae, hemolysin, K capsules and sensitive to human serumcidal activity caused incipient and acute pyelonephritis. Even among identical serotypes and biotypes, the presence/absence of fimbriae did not appear to be the critical factor in urovirulence, nor did the presence of several positive characteristics (hemolysin, K capsule, flagella, serum resistance) in a given strain enhance uropathogenicity. Therefore, these properties do not need to work together to render an E. coli urovirulent. These phenotypic characters may simply represent associated or serologic markers with the host serving as the dominant determinant of susceptibility to urinary infection. The findings emphasize the inherent limitations in relating and extrapolating colonizing and invasive properties of genetically engineered strains to those of naturally occurring, wild-type E. coli human uroisolates causing pyelonephritis.
Adhesins, Escherichia coli↗
Human choriogonadotropin-like material in bacteria of different species: electron microscopy and immunocytochemical studies with monoclonal and polyclonal antibodies.
Immunocytochemical studies using antisera to whole human choriogonadotropin (hCG), to its alpha- and beta-subunits and to the COOH-terminal peptide of hCG beta, and two monoclonal antibodies to hCG beta, demonstrated expression of hCG-like material, its individual subunits and/or fragments in nine bacterial strains. Seven of these were isolated from patients with cancer and were definitely identified as Streptococcus faecalis (three strains), Staphylococcus haemolyticus (two strains) and Staphylococcus epidermidis and Escherichia coli (single strains). The other two strains were cell-wall-deficient (CWD) variants, one identified as Streptococcus bovis, isolated from the blood of a patient with a fever of unknown origin and a possible brain abscess. The other was a Gram-negative diphtheroid isolated from the urine of a pregnant woman, which during the period of study reverted to a Gram-positive Corynebacterium identified as a 'C. ulcerans' strain and expressed the hCG-like factor only during its phase as Gram-negative diphtheroid. Electron microscopy of these nine strains (including negative controls of strains of the same species subjected to the same immunocytochemical analyses and under identical cultural conditions) revealed morphological alterations in the bacterial cell walls and cytoplasmic material and/or bizarre forms of reproduction in six of the nine strains expressing hCG-like material including the two CWD variants. Collectively, these results provided evidence that (1) hCG-producing bacteria isolated from patients with overt cancer are not a new and unique species as claimed by others, and (2) there is a close resemblance between the bacterial protein and the human trophoblastic hormone, based on immunochemical recognition of different parts of the hCG molecule.(ABSTRACT TRUNCATED AT 250 WORDS)
Antibodies, Monoclonal↗
Host-parasite relationships in acute pyelonephritis.
During a 1-year prospective study, a total of 15 patients (seven children and eight adults) were observed with acute nonobstructive pyelonephritis. P-fimbriated Escherichia coli was the causative pathogen in all 15 patients. The same serotype of E coli that was P-fimbriated was isolated from the vaginal introitus of 60% and from the fecal flora of 86% of these patients. The only host abnormality was moderate vesicoureteral reflux in 20% of the patients. Uroepithelial cells were isolated from the first morning-voided urine from patients, who had recovered from pyelonephritis, and from age-matched controls. Using fluorescein-labelled type 1 and P-fimbriated reference strains of E coli and fluorescence-activated cell sorting (FACS) analysis, we evaluated their ability to adhere to these uroepithelial cells. P-fimbriated E coli was more adherent than type 1 fimbriated E coli, and more P-fimbriated E coli adhered to the patients' cells. Our data show that both colonization with P-fimbriated strains of E coli and receptor availability are important in the pathogenesis of pyelonephritis.
Acute Disease↗
Antibodies to bacterial vaccines demonstrating specificity for human choriogonadotropin (hCG) and immunochemical detection of hCG-like factor in subcellular bacterial fractions.
Investigations were done to determine whether vaccines prepared with chemically killed Staphylococcus haemolyticus RU1 and Streptococcus bovis AV46 (bacteria that have been demonstrated to express human choriogonadotropin [hCG]-like material on their surface) elicited antibodies in rabbits with specificity for hCG determinants. In addition, the anatomical locus of the hCG-like factor was determined by separation of bacterial subcellular fractions. The results demonstrated that these bacterial vaccines elicited antibodies immunologically similar to those antibodies produced in response to the whole human trophoblastic hormone, a similarity extending even to cross-reactivity with human luteinizing hormone. The bacterial hCG-like material appeared to be localized in the membranes of the cell wall, and most was present in the soluble membranous and cytoplasmic constituents. Its expression in bacteria was a strain characteristic and not a species characteristic.
Animals↗
Pathogenic significance of P-fimbriated Escherichia coli in urinary tract infections.
The over-all aim of this study was to determine the pathogenic significance, and bacteriological and serological characteristics of P-fimbriated organisms isolated from a general population of patients with bacteriuria. A P-receptor specific particle agglutination test was used to identify P-fimbriated bacteria among 2,010 isolates from male and female patients with bacteriuria (age range infancy to 91 years). Of the 2,010 isolates 206 (10.2 per cent) were positive for P-fimbriae by the P-receptor specific particle agglutination test. Only Escherichia coli was found to be P-fimbriated, with an incidence of 21.5 per cent among 956 Escherichia coli isolates. The critical characteristic of pyelonephritic strains of Escherichia coli was P-fimbriation. In cases of nonobstructive acute pyelonephritis 100 per cent of the infecting bacteria were P-fimbriated. The data indicated clearly that the serotype, biotype, presence of type 1 fimbriae (mannose sensitive), undefined mannose-resistant adhesions, hemolysin production and motility of P-fimbriated Escherichia coli were clinically unimportant differential strain characteristics and not indicative of the virulence of P-fimbriated Escherichia coli within clinical syndromes. Isogenic P-fimbriated Escherichia coli strains were isolated from noncompromised patients in all clinical categories, that is pyelonephritis, asymptomatic bacteriuria and cystitis. A variety of bacterial strains appears to be capable of causing acute pyelonephritis in the presence of obstructive uropathic conditions, regardless of P-fimbriation. Therefore, P-fimbriation becomes a noncritical factor in compromised patients. The P-receptor specific particle agglutination test is a simple and rapid method to determine whether bacteria are P-fimbriated and may be an important screening method to identify those bacteria isolated from individuals at risk for nonobstructive acute pyelonephritis.
Agglutination Tests↗
Antigenic and immunogenic characteristics of subcellular fractions and whole cells of a rough E. coli 0111 (J5) mutant.
Little information is available on the antigenic and immunogenic properties of an E. coli rough mutant: J5 derived from E. coli 0111:B4, and the relationship of J5 to other cross-reacting antigens of Enterobacteriaceae. Subcellular fractions of J5 and various antigen preparations were tested against antisera to Enterobacterial Common Antigen (ECA-Kunin) and to the Re mutant of S. minnesota (R595). ECA-Kunin was demonstrated in all subcellular fractions of the J5 mutant by means of indirect hemagglutination and by hemagglutination inhibition tests. This common antigen was separable from J5 LPS by ethanol fractionation and by phenol-chloroform-petroleum ether extraction. Treatment with alkali destroyed the hemagglutinating reactivity of ECA-Kunin and revealed the complex nature of J5 surface antigens; an alkalinized 20p30 fraction (containing cell wall components) contained both specific J5 antigen and an antigen which cross-reacted with S. minnesota and S. typhimurium. This antigen was shown by absorption studies to be a new common antigen other than Re LPS or ECA-Kunin. Studies of J5 LPS by ELISA demonstrated that there was a shared cross-reactive immunodeterminant between the glycolipids of J5 and Re. Accordingly, heat-killed J5 preparations were complex vaccines which were able to elicit an antibody response with at least two specificities: ECA-Kunin and the specific J5 antigen.
Antibodies, Bacterial↗
Cross-reactive immunoprotective antibodies to Escherichia coli O111 rough mutant J5.
The potential immunoprotective role of antiserum to an Escherichia coli J5 mutant derived from E. coli O111:B4 was demonstrated in an experimental mouse model. Overwhelming bacterial inocula masked the effects of cross-reactive immunoprotection due to antiserum to strain J5. Enhanced bacterial clearance was observed in mice receiving antiserum to strain J5 in sublethal infections but not from lethal doses. Incorporation of hemoglobin with the bacterial inocula decreased the 50% lethal dose of challenge organisms, allowing the demonstration of protective activity of antiserum to strain J5 in lethal infection. Pretreatment of mice with antiserum to strain J5 did not protect against lethal doses of endotoxin. The protective factor was demonstrated by exhaustive adsorption experiments to be an antibody specific for strain J5 lipopolysaccharide. The protective activity of antiserum to strain J5 was abolished only after adsorption with strain J5 lipopolysaccharide but not with Salmonella typhimurium mutants with or without enterobacterial common antigen.
Animals↗
Immunology of pyelonephritis in the primate model. II. Effect on immunosuppression.
Nonobstructive pyelonephritis was produced in the rhesus monkey (Macaca mulatta) by means of retrograde inoculation of Escherichia coli to the point of pyelotubular backflow. The effects of treatment with cyclophosphamide or azathioprine were determined. Commensal renal viruses were not activated by the immunosuppression, and thus did not complicate our results. Both cyclophosphamide and azathioprine prolonged the bacteriuria and produced more severe pathology. Cyclophosphamide decreased the leukocytic response and partically suppressed the antibody response. The increased amount of acute pyelonecytic response and partially suppressed the antibody response. The increased amount of acute pyelonephritic lesions after treatment with this drug suggest that the antibody and inflammatory responses may be important protective mechanisms, particularly regarding prevention of abscesses. In contrast, azathioprine did not decrease the leukocytosis nor the antibody responses, but resulted in decreased in vitro responsiveness of lymphocytes to mitogens. The increased severity of chronic pyelonephritic lesions after azathioprine treatment suggests that the cellular immune response also may be an important protective mechanism during late stages of the disease. The results thus indicate that the immune response is protective and is not directly responsible for the chronic scarring of pyelonephritis.
Animals↗
Bacterial variants in urinary casts and renal epithelial cells.
Casts with numerous and unusually large granules were seen in the urine of a child with renal Fanconi's syndrome. When the urine sediment was sealed under a coverslip for several days, many granules changed to filamentous bacterial variants that segmented and, finally, appeared as streptococcal-like forms. When the patient's blood was cultured by a special method, bacterial variants grew consistently, and frequently reverted to parent coccal forms, although conventional cultures were negative. Variants from blood cultures had the same morphology and staining properties as granules in casts and in cystic structures found within hypertrophied renal pelvic epithelial cells. Cryptic parasitization with bacterial variants probably occurs in many nephropathies. Variants are known to produce toxins and immunogens, which could lead to mesangial and basement membrane deposits as well as to occlusive reactions in the renal microcirculation.
Atypical Bacterial Forms↗
Vasectomy in rhesus monkeys. IV. Electron microscopic studies of the seminiferous epithelium.
Explore the source record for details and available documents.
Animals↗
Vasectomy in rhesus monkeys. III. Light microscopic studies of testicular morphology.
Rhesus monkeys were randomly assigned to undergo various surgical procedures. The animals were followed from one to sixty-six weeks postvasectomy, at which time they were sacrificed and their tissues prepared for light and electron microscopy. Vasectomy in the rhesus monkey, as in certain other species, appears to be a procedure not attended with widespread testicular atrophy or histologic evidence of impaired spermatogenic potential utilizing the procedures and postoperative periods studied. Why certain animals exhibited focal degenerative changes is unclear; perhaps a certain population, yet to be defined, is more sensitive to such procedures, resulting in testicular alterations. It is important that such a population and such changes be defined to predict more accurately the possibility of successful vasovasostomy and reestablishment of fertility.
Animals↗
Novel bacterial structures in human blood. II. Bacterial variants as etiologic agents in idiopathic hematuria.
Novel bacterial structures have been demonstrated in lysed blood filtrates placed in special culture media from patients with idiopathic hematuria. These structures converted rapidly to gram-positive coccal (streptococcal and staphylococcal-like), coccobacillary and filamentous, bacterial forms in vitro from 96 per cent of the patients studied. Blood cultured conventionally yielded negative findings. Although structures (dense bodies) were demonstrated in normal control blood specimens (albeit in lesser numbers) few converted to classical bacteria in vitro (7 per cent). Erythromycin therapy appeared to correlate with disappearance of hematuria and inability to revert rapidly the variant forms to classical bacteria in vitro. It is suggested that continual bombardment of the blood by bacteria entering from the mouth or other sites may lead to the development of variant bacterial parasitism. In an effort to survive the deleterious host effects the organisms may convert to persisting osmotically stable variant bacterial forms (dense bodies). Development of a disease state may be conditioned by some existing or developing abnormality in the host (immunologic, physiologic and/or biochemical). Furthermore, changes (genetic?) that might take place in the organisms per se during their transition to variant forms and adaptation to life in vivo may not allow certain host environments to adapt to these new forms, possibly leading to a pathogenetic role in renal diseases whose etiologies have long been enigmas.
Adolescent↗
Vasectomy in rhesus monkeys I. Surgical techniques and gross observations.
Vasectomy and vaso-occlusion techniques were used in 47 male rhesus monkeys to maximize and minimize the amount of sperm allowed to escape from the vas into surrounding tissues for up to seventy-two weeks postoperatively. Body weight changes and blood clinical data indicated that the general health of all the monkeys remained good. Normal seasonal changes in body weights and testicular volumes suggested that there were no disturbances to the endocrine system and that the monkeys remained responsive to seasonal environmental stimuli. Vasectomy appears to cause no short-term deleterious effects in the rhesus monkeys, based on observations made during the seventy-two weeks that these monkeys were study after vasectomy. This conclusion agrees with the findings of other investigators.
Animals↗
Vasectomy in rhesus monkeys II. Failure to demonstrate dumoral and cellular immune responses specific for sperm.
Explore the source record for details and available documents.
Animals↗
Novel bacterial structures in human blood: cultural isolation.
Evidence for the existence of a novel bacteriological system has been obtained from osmotically lysed and filtered human blood (membrane filters with a pore size of 0.22 micronm) placed in special culture media. These blood filtrates gave rise to ordinary bacteria for 71% of the blood specimens processed from diseased humans and for 7% of those from supposedly normal humans. Morphologically, the bacteria resembled streptococcal, staphylococcal, and gram-positive filamentous (cocco-bacillary) forms. Prior to the appearance of bacteria in the media, large and small "dense bodies" were microscopically observed but disappeared when ordinary bacteria were apparent, Cultures of of unlysed blood as conventionally performed were negative. These organisms may represent an adaptation of certain bacteria to life in the blood.
Bacteria↗