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PubMed1982

Comparison of coliphage and bacterial aerosols at a wastewater spray irrigation site.

Microbiological aerosols were measured on a spray irrigation site at Fort Huachuca, Ariz. Indigenous bacteria and tracer bacteriophage were sampled from sprays of chlorinated and unchlorinated secondary-treatment wastewaters during day and night periods. Aerosol dispersal and downwind migration were determined. Bacterial and coliphage f2 aerosols were sampled by using Andersen viable type stacked-sieve and high-volume electrostatic precipitator samplers. Bacterial standard plate counts averaged 2.4 x 10(5) colony-forming units per ml in unchlorinated effluents. Bacterial aerosols reached 500 bacteria per m3 at 152 m downwind and 10,500 bacteria per m3 at 46m. Seeded coliphage f2 averaged 4.0 x 10(5) plaque-forming units per ml in the effluent and were detected 563 m downwind. Downwind microbial aerosol levels were somewhat enhanced by nighttime conditions. The median aerodynamic particle size of the microbial aerosols was approximately 5.0 micrometer. Chlorination reduced wastewater bacterial levels 99.97% and reduced aerosol concentrations to near background levels; coliphage f2 was reduced only 95.4% in the chlorinated effluent and was readily measured 137 m downwind. Microbiological source strength an meteorological data were used in conjunction with a dispersion model to generate mathematical predictions of aerosol strength at various sampler locations. The mean calculated survival of aerosolized bacteria (standard plate count) in the range 46 to 76 m downwind was 5.2%, and that of coliphage f2 was 4.3 %.

Aerosols↗

PubMed2002

Linking of microorganisms to phenanthrene metabolism in soil by analysis of (13)C-labeled cell lipids.

Phenanthrene-metabolizing soil microbial communities were characterized by examining mineralization of [(14)C]phenanthrene, by most-probable-number (MPN) counting, by 16S-23S spacer DNA analysis of the numerically dominant, culturable phenanthrene-degrading isolates, and by examining incorporation of [(13)C]phenanthrene-derived carbon into sterols and polar lipid fatty acids (PLFAs). An unpolluted agricultural soil, a roadside soil diffusely polluted with polycyclic aromatic hydrocarbons (PAHs), and two highly PAH-polluted soils from industrial sites were analyzed. Microbial phenanthrene degraders were not detected by MPN counting in the agricultural soil and the roadside soil. In the industrial soils, phenanthrene degraders constituted 0.04 and 3.6% of the total number of CFU. 16S-23S spacer DNA analysis followed by partial 16S DNA sequencing of representative isolates from one of the industrial soils showed that one-half of the isolates belonged to the genus Sphingomonas and the other half were closely related to an unclassified beta-proteobacterium. The (13)C-PLFA profiles of the two industrial soils were relatively similar and resembled the profiles of phenanthrene-degrading Sphingomonas reference strains and unclassified beta-proteobacterium isolates but did not match the profiles of Pseudomonas, Mycobacterium, or Nocardia reference strains. The (13)C-PLFA profiles of phenanthrene degraders in the agricultural soil and the roadside soil were different from each other and different from the profiles of the highly polluted industrial soils. Only in the roadside soil were 10me/12me18:0 PLFAs enriched in (13)C, suggesting that actinomycetes metabolized phenanthrene in this soil. The (13)C-PLFA profiles of the unpolluted agricultural soil did not resemble the profiles of any of the reference strains. In all of the soils investigated, no excess (13)C was recovered in the 18:2omega6,9 PLFA, suggesting that fungi did not contribute significantly to assimilation of [(13)C]phenanthrene.

Bacteria↗

PubMed2006

TLRs in the Gut I. The role of TLRs/Nods in intestinal development and homeostasis.

The innate immune system includes microbial pattern recognition receptors that detect bacteria and viral products at the cell surface, in vesicles, and within the cytoplasm. Transmembrane signaling occurs through Toll-like receptors (TLRs). Cytoplasmic receptors are generally members of the nucleotide-binding domain (NOD)-leucine-rich repeat (LRR) family (CATERPILLER family). They influence the effects of other family members and of TLRs. Most NOD-LRR members enhance signal transduction, but Monarch-1 counterbalances TLR activity. NOD-LRR family members also act within the adaptive immune system. The class II transactivator regulates major histocompatibility complex class II expression. In the intestine, it is developmentally regulated, and its expression depends on weaning and, independently, on age.

Animals↗

PubMed2006

Factors affecting the morbidity of contact lens-related microbial keratitis: a population study.

PURPOSE: To examine factors influencing the severity of soft contact lens (SCL)-related microbial keratitis. METHODS: Cases were detected via surveillance studies in Australia and New Zealand. Factors affecting disease severity (costs, days of symptoms, and 2 or more lines of vision loss) were examined and included age; gender; delay in SCL removal, seeking consultation, or receiving treatment; overnight wear; SCL material (hydrogel or silicone hydrogel [SiH]); and causative organism. RESULTS: Two hundred ninety-seven cases were identified: 61% female, age: 35 +/- 13 years (mean +/- SD). Treatment costs were (median [interquartile range]) $760 [1859] and indirect costs were $468 [1810]. Patients were symptomatic for 7 [11] days, and vision loss occurred in 14.3% of cases. Cases with pathogenic causative organisms (66/297, 22%) were 11.4 times (95% confidence interval [CI], 4.2-30.9) more likely to result in vision loss, had longer duration of symptoms (21 [40] vs. 6 [8] days, P < 0.001) and incurred higher costs (5,512 [14,733] vs. 1,048[8,325], P < 0.001). Delays (>12 hours) before treatment increased the likelihood of vision loss (P = 0.048) disease duration (P = 0.004), and associated costs (P = 0.009). Remoteness increased the risk of vision loss (odds ratio [OR] = 5.1; 95% CI 1.6-16.6), and individuals over 28 years of age had longer disease duration (P = 0.02). In overnight wear and after adjustment for culture result and treatment delays, SiH wearers had slightly shorter disease duration (4 [4] vs. 7 [10] days, P = 0.02) but a rate of vision loss and cost similar to those of hydrogel wearers. CONCLUSIONS: The causative organism was the major determinant of severity; however, modifiable factors such as delays in treatment had considerable influence. Duration of symptoms was shorter in SiH wearers, but other factors dominated disease outcome in this population study.

Adolescent↗

PubMed2006

TLR9 and the recognition of self and non-self nucleic acids.

Toll-like receptors (TLRs) are involved in the innate recognition of foreign material and their activation leads to both innate and adaptive immune responses directed against invading pathogens. TLR9 is intracellularly expressed in the endo-lysosomal compartments of specialized immune cells. TLR9 is activated in response to DNA, in particular DNA containing unmethylated CpG motifs that are more prevalent in microbial than mammalian DNA. By detecting foreign DNA signatures TLR9 can sense the presence of certain viruses or bacteria inside the cell and mount an immune response. However, under certain conditions, TLR9 can also recognize self-DNA and this may promote immune pathologies with uncontrolled chronic inflammation. The autoimmune disease systemic lupus erythematosis (SLE) is characterized by the presence of immune stimulatory complexes containing autoantibodies against endogenous DNA and DNA- and RNA-associated proteins. Recent evidence indicates that the autoimmune response to these complexes involves TLR9 and the related single-stranded RNA-responsive TLRs 7 and 8, and therefore some breakdown in the normal ability of these TLRs to distinguish self and foreign DNA. Evidence suggests that immune cells use several mechanisms to discriminate between stimulatory and nonstimulatory DNA; however, it appears that TLR9 itself binds rather indiscriminately to a broad range of DNAs. We therefore propose that there is an additional recognition step by which TLR9 senses differences in the structures of bound DNA.

Autoantibodies↗

PubMed2005

Human colon microbiota transform polycyclic aromatic hydrocarbons to estrogenic metabolites.

Ingestion is an important exposure route for polycyclic aromatic hydrocarbons (PAHs) to enter the human body. Although the formation of hazardous PAH metabolites by human biotransformation enzymes is well documented, nothing is known about the PAH transformation potency of human intestinal microbiota. Using a gastrointestinal simulator, we show that human intestinal microbiota can also bioactivate PAHs, more in particular to estrogenic metabolites. PAH compounds are not estrogenic, and indeed, stomach and small intestine digestions of 62.5 nmol naphthalene, phenanthrene, pyrene, and benzo(a)pyrene showed no estrogenic effects in the human estrogen receptor bioassay. In contrast, colon digests of these PAH compounds displayed estrogenicity, equivalent to 0.31, 2.14, 2.70, and 1.48 nmol 17alpha-ethynylestradiol (EE2), respectively. Inactivating the colon microbiota eliminated these estrogenic effects. Liquid chromatography-mass spectrometry analysis confirmed the microbial PAH transformation by the detection of PAH metabolites 1-hydroxypyrene and 7-hydroxybenzo(a)pyrene in colon digests of pyrene and benzo(a)pyrene. Furthermore, we show that colon digests of a PAH-contaminated soil (simulated ingestion dose of 5 g/day) displayed estrogenic activity equivalent to 0.58 nmol EE2, whereas stomach or small intestine digests did not. Although the matrix in which PAHs are ingested may result in lower exposure concentrations in the gut, our results imply that the PAH bioactivation potency of colon microbiota is not eliminated by the presence of soil. Moreover, because PAH toxicity is also linked to estrogenicity of the compounds, the PAH bioactivation potency of colon microbiota suggests that current risk assessment may underestimate the risk from ingested PAHs.

Administration, Oral↗

PubMed1991

Collagenolytic enzymes assayed by spectrophotometry with suspensions of reconstituted collagen fibrils.

Collagenolytic enzymes were quantitated by a method based on spectrophotometry of suspended reconstituted collagen fibrils. To obtain optically stable suspensions it was necessary to perform a short sonication of the aggregated fibrils at 10 degrees C. When fibrils were cleaved with mammalian fibroblast collagenase at 35 degrees C the triple helical collagen fragments (TCA and TCB) would uncoil spontaneously and the decreasing turbidity was used as an estimate of enzyme activity. The method is a specific collagenase assay since a possible cleavage in the non-helical parts of the collagen molecule with contaminating proteinases is without effect on the turbidity of the suspension and the collagen substrate is not converted to gelatin at 35 degrees C. After 1 h of incubation 0.2 U (equivalent to 0.2 micrograms) of fibroblast collagenase could be detected. In purification procedures with microbial collagenases many fractions were tested by overnight incubations in disposable cuvettes. Sealing of cuvettes with square silicone stoppers allowed rotation of enzyme-substrate mixtures directly in the cuvettes. Only standard laboratory equipment is required for this assay, which is not dependent on radiolabeling or preparation of specific immunologic reagents.

Animals↗

PubMed1995

Macrosphelide, a novel inhibitor of cell-cell adhesion molecule. I. Taxonomy, fermentation, isolation and biological activities.

Potent anti-adherent activity was detected in fermentation extracts of microbial strain FO-5050. Active compounds designated macrosphelide A and B were isolated and the structure was determined to be 16-membered macrolide antibiotics possessing three ester bonds in the ring structure. Macrosphelide A dose-dependently inhibited the adhesion of HL-60 cells to LPS-activated HUVEC monolayer (IC50, 3.5 microM); macrophelide B also inhibited HL-60 adhesion but to a lesser extent (IL50, 36 microM). Macrosphelide A did not show any antimicrobial and cytocidal activities at the concentration of 1000 micrograms/ml and 100 micrograms/ml, respectively.

Anti-Bacterial Agents↗

PubMedDate not supplied

[The role of different microorganisms in the genesis of tubal-peritoneal infertility and in immunity].

The character of microflora, directly causing inflammatory process in tuboperitoneal infertility, was studied. The study revealed the prevalence of microbial associations, Chlamydia infection was detected in half of the women, and in 17% of the patients this infection was for the first time detected in the upper section of their reproductive apparatus, which was indicative of the role of Chlamydia infection in the occlusion of the uterine tubes. Opportunistic microflora persisting in persons with defective antimicrobial protection was found. The study of local protective factors in peritoneal fluid revealed the absence of T-cell activity, which was manifested by a low level of sIL-2R and the absence of a significant rise in the level of IL-2 in peritoneal fluid in comparison with that in healthy women. In addition, a decrease in the total complement activity and in the activity of component C3 of the complement was established.

Adult↗

PubMed1999

Changing aetiology of urinary tract infections and emergence of drug resistance as a major problem.

A study was undertaken to ascertain the spectrum of causative agents responsible for UTI and to detect the magnitude of anti microbial resistance in aetiological agents. Klebsiella species caused urinary tract infection in maximum number of cases (124, 37.35%) followed by Escherichia coli (114, 34.4%), Pseudomonas aeruginosa 32 (9.64%) and Staphylococcus aureus 23 (6.93%). Other organisms caused urinary tract infection in 39 (11.75%) cases. Resistance to gentamicin was observed in 83% S. aureus, 84.7% Klebsiella species, 78.1% Escherichia coli, 71.9% Pseudomonas aeruginosa and 94.8% of remaining isolates. A large number of isolates (> 90%) were resistant to ampicillin, Cotrimoxazole erythromycin, and chloramphenicol. All the isolates of S.aureus were resistant to penicillin. This observations indicate extremely high degree of resistance in urinary pathogen and warrant change in antibiotic usage as well as formulation of policy for rational use of antibiotics.

Drug Resistance, Microbial↗

PubMedDate not supplied

Th1-like and Th2-like cytokines in patients undergoing open versus laparascopic cholecystectomy.

The advantages of laparoscopic (LC versus, open cholecystectomy (OC) seems to be related to minimal invasive procedure and to the moderate inflammatory response. The aim of this study is to define the involvement of Th1 (IFN-gamma) and Th2 (IL-4, IL-6, IL-10, IL-13) cytokines production in vivo and in vitro in patients undergoing OC or LC. In 42 patients undergoing LC (n = 22) and OC (n = 20) Th1-like and Th2-like was evaluated before operation and at 6, 24 and 48 hours after operation for white blood cell counting and cytokines (IL-4, IL-6, IL-10, IL-13, IFN-gamma, TNF-alpha) in the sera and in the supernatants from circulating mononuclear cells stimulated with phytohemagglutinin or lipopolysaccharide. The acute phase response cytokine, IL-6, appeared significantly increased following OC than after LC. All other cytokines did not very significantly. In vitro data shows a reduction of IFN-gamma and increase in Th2-like cytokines in OC patients compared with the basal value. In LC subjects we observed an high production of IFN-gamma associated to an increase of Th2-like cytokines, like IL-10 and IL-13, even though IL-4 and IL-6 were unmodified. In contrast to OC, LC did not significantly affect immunocompetence, maintaining a moderate inflammatory response and an adequate balance between Th1 and Th2 cytokine. Furthermore, the strong activation of cells producing Th1-like cytokines in LC patients following mitogen activation indicated a consistent anti-microbial activity, that was not detectable in OC patients, that showed after activation only a Th2 response.

Adult↗

PubMedDate not supplied

[Clinical and diagnostic importance of the evaluation of the Ig proteases activity in children with intestinal dysbacteriosis].

The specific activity of serine, metal dependent and thiolic Ig proteases in the coprofiltrates of children with manifestations of intestinal dysbacteriosis was determined by the enzyme immunoassay. 56 children with pronounced symptoms of intestinal disorders (37 children aged up to 1 year and 19 children over 1 year) were examined. A group of 25 clinically healthy children was used as control. Simultaneously with protease activity of coprofiltrates, there was detected the level of Ig-degrading activity of the opportunistic bacteria islolates of different taxonomic groups from feces of children with dysbacteriosis of different severity (as determined by the classical bacteriological method). The evaluation of the Ig-proteolytic activity of fecal supernatants, associated with the presence of serine, metal-dependent and thiolic proteases in the intestine, as well as detection of such proteases in microbial isolates, seems to be highly important for the diagnosis of intestinal disorders in children and is recommended for screening of intestinal dysbacteriosis.

Bacterial Infections↗

PubMed1990

Gynecological abnormalities following allogeneic bone marrow transplantation.

Forty-four post-pubertal women were studied 261-4628 days after allogeneic transplantation to determine the nature and degree of gynecological abnormalities following bone marrow transplantation. Evaluations included pelvic examinations, exfoliative cytology, serum gonadotropin levels, direct preparations for micro-organisms, and microbial cultures. Pelvic abnormalities were detected in 35 of 44 (80%) women and resembled atrophic changes known to occur after ovarian failure. Findings included reduced vaginal elasticity and rugal folds, pale tissues, small vaginal, uterine and cervical size, atrophic vulvovaginitis, introital stenosis, and loss of pubic hair. Atrophic abnormalities were noted in 33 of 36 recipients of total body irradiation (TBI) compared to two of eight women not prepared with TBI (p = 0.02). Vasomotor symptoms were reported in 67% of TBI recipients compared to 38% of those not given TBI. Elevated serum gonadotropin levels suggested that TBI had caused the ovarian failure. Recognition of these gynecological abnormalities can lead to earlier hormone replacement, alleviating unnecessary discomfort and improving the well-being of the marrow transplant recipient.

Adolescent↗

PubMed1989

[The mutagenicity of organic microcontaminants in the environment. IV. The mutagenicity of volatile organic halogens in the SOS-chromotest].

To determine the sensitivity and responsibility of microbial shortterm-tests for detection of the mutagenic potency of volatile halogenated hydrocarbons (OHC) 18 pure substances from the groups of halomethanes, -ethanes and ethylenes were examined with the SOS-Chromotest. The strain Escherichia coli PQ37 was used in the standard procedure (macro procedure) with and without metabolic activation by Aroclor 1254 induced rat-liver microsomes. Although the selected OHC were tested to high doses, none of the tested compounds showed mutagenic effects in Escherichia coli PQ37. Also those OHC's, which showed positive results in the Ames test or being suspected of carcinogenicity, showed no positive results in the SOS-Chromotest. Therefore, the standard procedure of SOS-Chromotest is not suitable to detect the mutagenicity of volatile organic and halogenated compounds. Supplementary investigations with modified methods are necessary to check the results, because there is a good correlation between Ames test and SOS-Chromotest by testing other groups of compounds.

Animals↗

PubMed1977

Application of gas chromatography to diagnosis of microorganisms and infectious diseases.

Gas chromatography (GC) can be used to characterize microorganisms chemically. Microbial whole cells and cell extracts can be analysed by GC after being thermally or chemically degraded, i.e. pyrolysed or hydrolysed. Microbial metabolic products can be detected by GC analysis of culture media or the atmosphere above such media, i.e. headspace analysis. Pyrolysis products can be analysed direct, while hydrolysis products and non-volatile metabolites must be derivatized before being chromatographed. Differences in the chromatographic patterns can be used to differentiate between microorganisms. Detection of metabolic products in body fluids by means of GC constitutes a potential technique for the rapid diagnosis of infectious diseases.

Chromatography, Gas↗

PubMed1986

Serious infection in the intensive therapy unit: a 15-year study of bacteraemia.

A 15-year prospective study identified 468 episodes of bacteraemia in patients in the intensive therapy unit (containing 12 beds). The mortality was 60.4 per cent compared with 13.1 per cent in those without detectable bacteraemia. The pattern of microbial isolates was similar to that in bacteraemia elsewhere in the hospital except for a relative excess of pseudomonas and yeasts. The commonest isolates were staphylococci; the source of these organisms was an infected intravenous line in two-thirds of hospital-acquired episodes of bacteraemia in the unit. Antibiotic resistance patterns were largely predictable with gentamicin resistance being especially uncommon. Although bacteraemia poses a serious threat to patients in an intensive therapy unit, the treatment of such infection seldom requires new and expensive antibiotics.

Anti-Bacterial Agents↗

PubMed1982

Production of interferon and other lymphokines during murine tumour growth. III. Characterization of microbial growth inhibitory activity in cell-free supernatants of rat Zajdela ascites hepatoma.

A microbial growth inhibitory factor (MGIF) detected in the cell-free fluid of Zajdela ascites hepatoma of the rat was characterized by means of gel filtration, ion exchange chromatography and isoelectric focusing. It was shown that MGIF is a nondialysable protein with a molecular weight of about 19,000 to 25,000. Charge heterogeneity was revealed by isoelectric focusing which demonstrated pI of 3.8--4.5 and 5.0--6.0. MGIF seems to differ from tumour cell-derived MIF detected in the same ascitic fluids.

Ammonium Sulfate↗

PubMed1983

Monoclonal antibodies: methods and clinical laboratory applications.

Kohler and Milstein have shown that individual clones of normal antibody-secreting lymphocytes could be immortalized by fusion with myeloma cells. These investigators initiated a new era of technology with the successful in vitro production of monoclonal antibodies via somatic cell hybridization. With the use of monoclonal antibodies, many major problems arising from the limited specificity and reproducibility of conventional antisera can be solved. Some of the commonly employed methods for the production of monoclonal antibody are: (1) fusion of sensitized lymphocytes and myelomas from different sources to produce continuous antibody-producing cell lines; (2) in vitro viral transformation of sensitized lymphocytes to form continuous antibody-producing cells; (3) hybrid fusion of sensitized lymphocytes and continuous B lymphocyte cell lines. During the past few years, monoclonal antibody methodology has been used in almost every area of biological research. Monoclonal antibodies have been used as structural probes for proteins and hormones, and as highly specific agents for histocompatibility testing, tumor localization, immunotherapy, purification of molecules, identification of new surface antigens on lymphocytes and tumor cells, and detection of drug levels and microbial and parasitic diseases. In addition, several investigators have developed alternative methods for the production of human as well as mouse and rat monoclonal antibodies. The new technology of in vitro production of animal and human monoclonal antibodies will have many future applications in diagnosis and therapy in laboratory and clinical medicine.

Animals↗