RESUMEN
OBJECTIVE: Based on its expression profile, folate receptor alpha (FRA) is an attractive candidate for targeted diagnostics and therapeutics. However, applicability of these agents in residual or recurrent disease could be influenced by chemotherapy. We evaluated whether chemotherapy modified FRA expression in non-mucinous epithelial ovarian (EOC) and endometrial carcinoma (EC). METHODS: FRA staining was evaluated by immunohistochemistry, using MAb 26B3, in 81 patients (41 EOCs and 40 ECs) and 17 control tissues (5 benign ovarian cysts, 5 normal ovarian, and 7 normal endometrial tissues). Chemotherapy effect was evaluated in 42 patients (30 paired samples at primary and interval debulking surgery and 12 from primary and recurrent disease). FRA expression was assessed using a semi-quantitative staining algorithm, the M-score (range 0-50). RESULTS: Median difference in M-score between tumor and control samples was 27.5 for EOC (95% CI 10.0 to 45.0) and 6.7 for EC (95% CI -6.7 to 21.7). Paired samples from both primary and interval debulking surgery did not differ in FRA expression in EOC (median difference of M-score between paired samples of 0.0 [95% CI -2.6 to 2.6]). Recurrent EOC tumors reflected FRA status at diagnosis (median difference of M-score between paired samples of 3.3 [95% CI -7.0 to 13.6]). CONCLUSIONS: This study shows no significant difference in FRA expression after chemotherapy, strengthening the rationale for FRA targeted diagnostics and therapeutics in FRA expressing tumors, whether newly diagnosed or at recurrence.
Asunto(s)
Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/metabolismo , Receptor 1 de Folato/biosíntesis , Neoplasias Glandulares y Epiteliales/tratamiento farmacológico , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Carcinoma Epitelial de Ovario , Estudios de Casos y Controles , Estudios de Cohortes , Neoplasias Endometriales/patología , Femenino , Humanos , Inmunohistoquímica , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Estudios RetrospectivosRESUMEN
We have investigated bottom-up chemical synthesis of quaternary ammonium (QA) groups exhibiting antibacterial properties on stainless steel (SS) and filter paper surfaces via nonequilibrium, low-pressure plasma-enhanced functionalization. Ethylenediamine (ED) plasma under suitable conditions generated films rich in secondary and tertiary amines. These functional structures were covalently attached to the SS surface by treating SS with O 2 and hexamethyldisiloxane plasma prior to ED plasma treatment. QA structures were formed by reaction of the plasma-deposited amines with hexyl bromide and subsequently with methyl iodide. Structural compositions were examined by electron spectroscopy for chemical analysis and Fourier transform infrared spectroscopy, and surface topography was investigated with atomic force microscopy and water contact angle measurements. Modified SS surfaces exhibited greater than a 99.9% decrease in Staphylococcus aureus counts and 98% in the case of Klebsiella pneumoniae. The porous filter paper surfaces with immobilized QA groups inactivated 98.7% and 96.8% of S. aureus and K. pneumoniae, respectively. This technique will open up a novel way for the synthesis of stable and very efficient bactericidal surfaces with potential applications in development of advanced medical devices and implants with antimicrobial surfaces.
Asunto(s)
Antibacterianos/síntesis química , Celulosa/química , Klebsiella pneumoniae/efectos de los fármacos , Compuestos de Amonio Cuaternario/síntesis química , Compuestos de Amonio Cuaternario/farmacología , Acero Inoxidable/química , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Filtración , Microscopía de Fuerza Atómica , Compuestos de Amonio Cuaternario/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Agua/químicaRESUMEN
Relatively little is known about how growth as a biofilm affects the virulence of pathogenic bacteria. In this study, the virulence of Salmonella typhimurium grown as a biofilm, or as planktonic cells, was compared in mice. Increased numbers of colony forming units were recovered from the spleens of mice 5 days after i.p. injection with S. typhimurium grown as a biofilm, as compared with planktonic cells (P < 0.05). No significant difference in the CFU of S. typhimurium recovered from the liver was noted at the same time point, and no difference was noted in the CFU recovered from the spleen or liver at 5 days after i.v. or i.g. inoculation with 10(5) S. typhimurium. Nor were any differences noted at 7 days after i.p., i.v. or i.g. inoculation. Thus, any effect of growth as a biofilm has on the virulence of S. typhimurium seems to be limited to the first 5 days after i.p. inoculation.
Asunto(s)
Biopelículas/crecimiento & desarrollo , Salmonelosis Animal/microbiología , Salmonella typhimurium/fisiología , Salmonella typhimurium/patogenicidad , Animales , Recuento de Colonia Microbiana , Inyecciones Intraperitoneales , Inyecciones Intravenosas , Hígado/microbiología , Masculino , Ratones , Ratones Endogámicos ICR , Bazo/microbiología , VirulenciaRESUMEN
Defects in cheese, such as undesirable flavors, gas formation, or white surface haze from calcium lactate crystals, can result from growth of nonstarter lactic acid bacteria (NSLAB). The potential for biofilm formation by NSLAB during cheese manufacturing, the effect of cleaning and sanitizing on the biofilm, and bacterial growth and formation of defects during ripening of the contaminated cheese were studied. Stirred-curd Cheddar cheese was made in the presence of stainless steel chips containing biofilms of either of two strains of erythromycin-resistant NSLAB (Lactobacillus curvatus strain JBL2126 or Lactobacillus fermentum strain AWL4001). During ripening, the cheese was assayed for total lactic acid bacteria, numbers of NSLAB, and percentage of lactic acid isomers. Biofilms of L. curvatus formed during cheese making survived the cleaning process and persisted in a subsequent batch of cheese. The starter culture also survived the cleaning process. Additionally, L. curvatus biofilms present in the vat dislodged, grew to high numbers, and caused a calcium lactate white haze defect in cheese during ripening. On the other hand, biofilms of L. fermentum sloughed off during cheese making but could not compete with other NSLAB present in cheese during ripening. Pulsed-field gel electrophoresis results verified the presence of the two biofilm strains during cheese making and in the ripening cheese. Probable contamination sites in the plant for other NSLAB isolated in the cheese were identified, thus supporting the hypothesis that resident NSLAB biofilms are a viable source of contamination in the dairy environment.
Asunto(s)
Biopelículas/crecimiento & desarrollo , Queso/microbiología , Lactobacillus/crecimiento & desarrollo , Compuestos de Calcio/análisis , Queso/análisis , Recuento de Colonia Microbiana , Electroforesis en Gel de Campo Pulsado , Fermentación , Contaminación de Alimentos , Manipulación de Alimentos , Microbiología de Alimentos , Isomerismo , Lactatos/análisis , Lactobacillus/clasificación , Lactobacillus/aislamiento & purificación , Saneamiento , Acero InoxidableRESUMEN
The levels to which microbial colony forming units are permitted in various waters fit for human contact are carefully regulated. Conventional chemical and physical approaches usually are complex processes with significant limitations due to the generation of toxic side-products. In this contribution a novel plasma reactor--dense medium plasma reactor--is described, and its efficiency for the disinfection of contaminated water is discussed. It has been shown that owing to the intense stirring of the reaction medium (e.g. contaminated water), as a result of the specially designed spinning electrode and gas-flow system, a volume-character discharge is created, which can efficiently kill bacteria. It has been demonstrated that treatment times as low as 20 s are enough for the total inactivation of microorganisms for 200 mL of 10(5) bacteria/mL contaminated water.
Asunto(s)
Bacterias , Purificación del Agua/métodos , Abastecimiento de Agua , Electroquímica , Electrodos , GasesRESUMEN
Bacillus cereus causes a highly fulminant endophthalmitis which usually results in blindness. We previously concluded that hemolysin BL (HBL), a tripartite necrotizing pore-forming toxin, is a probable endophthalmitis virulence factor because it is highly toxic to retinal tissue in vitro and in vivo. We also determined that B. cereus produces additional retinal toxins that might contribute to virulence. Here we fractionated crude B. cereus culture supernatant by anion-exchange chromatography and found that in vitro retinal toxicity was also associated with phosphatidylcholine-preferring phospholipase C (PC-PLC). The pure enzyme also caused retinal necrosis in vivo. We showed that phosphatidylinositol-specific PLC and sphingomyelinase were nontoxic and that two hemolysins, cereolysin O and a novel hemolysin designated hemolysin IV, were marginally toxic in vitro. The histopathology of experimental septic endophthalmitis in rabbits mimicked the pathology produced by pure HBL, and both HBL and PC-PLC were detected at toxic concentrations in infected vitreous fluid. Bacterial cells were first seen associated with the posterior margin of the lens and eventually were located throughout the lens cortex. Detection of collagenase in the vitreous humor suggested that infiltration was facilitated by the breakdown of the protective collagen lens capsule by that enzyme. This work supports our conclusion that HBL contributes to B. cereus virulence and implicates PC-PLC and collagenase as additional virulence factors.
Asunto(s)
Bacillus cereus/patogenicidad , Proteínas Bacterianas/toxicidad , Colagenasas/toxicidad , Endoftalmitis/etiología , Fosfolipasas de Tipo C/toxicidad , Secuencia de Aminoácidos , Animales , Western Blotting , Proteínas Hemolisinas , Presión Intraocular , Datos de Secuencia Molecular , Conejos , VirulenciaRESUMEN
Trisodium phosphate (TSP) has been approved by the United States Department of Agriculture as a post-chill antimicrobial treatment for raw poultry. This study examines the effectiveness of TSP against planktonic (suspended) and biofilm (attached) cells of Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes and Salmonella typhimurium at room temperature (RT) and 10 degrees C. At either temperature E. coli O157:H7 was the most sensitive to TSP treatments; 10(6) cfu/ml of planktonic or 10(5) cfu/cm2 of biofilm cells were eliminated by a 30 s treatment with 1% TSP. Campylobacter jejuni was slightly less sensitive. Listeria monocytogenes was the most resistant to the effect of TSP, requiring exposure to 8% TSP for 10 min (RT) or 20 min (10 degrees C) to reduce biofilm bacteria by at least one log. Biofilm cells of S. typhimurium and Listeria monocytogenes were more resistant than planktonic cells. Salmonella typhimurium was more sensitive to treatments using TSP at 10 degrees C than at RT. In contrast, L. monocytogenes was more resistant to TSP at 10 degrees C. Trisodium phosphate appears to be an effective treatment for reducing populations of C. jejuni, E. coli O157:H7 and S. typhimurium. This product has the potential to be used for reduction of bacterial counts on other food products besides raw poultry or on food and non-food contact surfaces.
Asunto(s)
Biopelículas , Campylobacter jejuni/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Microbiología de Alimentos , Listeria monocytogenes/efectos de los fármacos , Fosfatos/farmacología , Salmonella typhimurium/efectos de los fármacos , Animales , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Campylobacter jejuni/crecimiento & desarrollo , Recuento de Colonia Microbiana , Escherichia coli/crecimiento & desarrollo , Listeria monocytogenes/crecimiento & desarrollo , Aves de Corral/microbiología , Goma , Salmonella typhimurium/crecimiento & desarrollo , Acero Inoxidable , Propiedades de Superficie , TemperaturaRESUMEN
A histamine-producing strain of Lactobacillus buchneri was isolated from Swiss cheese that had been implicated in an outbreak of histamine poisoning. It produced up to 4,070 nmol of histamine per ml in MRS broth supplemented with 0.1% histidine. The identification of this isolate was based on its biochemical, bacteriological, and DNA characterizations.
Asunto(s)
Queso , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/microbiología , Histamina/biosíntesis , Lactobacillus/aislamiento & purificación , Histamina/envenenamiento , Humanos , Lactobacillus/metabolismo , Lactobacillus/patogenicidad , Especificidad de la EspecieRESUMEN
Multiply antibiotic-resistant strains of Clostridium perfringens were isolated from porcine feces. Strains that were resistant to tetracycline, erythromycin, clindamycin, and lincomycin were isolated, but no penicillin- or chloramphenicol-resistant strains were obtained. Typical minimal inhibitory concentrations for resistant strains were 16 to 64 mug of tetracycline per ml, 64 to >128 mug of erythromycin per ml, >/=128 mug of lincomycin per ml, and 16 to 128 mug of clindamycin per ml. Resistance to erythromycin was always associated with resistance to lincomycin and clindamycin. Minimal inhibitory concentrations were determined for 258 strains from six farms that used antibiotics in their feeds and 240 strains from five farms that did not use antibiotics. The results show that 77.9 and 22.7% of the strains from the former farms were resistant to tetracycline and erythromycin-clindamycin-lincomycin, respectively. The comparable data from the latter farms were 25.0 and 0.8%, respectively. Agarose gel electrophoresis failed to reveal a plasmid band that was common to the resistant strains but absent in the susceptible strains. Attempts to transfer tetracycline, erythromycin, and clindamycin resistance from one strain, CW459, were not successful. Antibiotic-susceptible mutants were not isolated from this strain, despite the use of a variety of curing agents.
Asunto(s)
Antibacterianos/farmacología , Clostridium perfringens/aislamiento & purificación , Heces/microbiología , Porcinos/microbiología , Animales , Clostridium perfringens/efectos de los fármacos , Clostridium perfringens/genética , Farmacorresistencia Microbiana , Factores RRESUMEN
Conditions for quantitation of Clostridium perfringens type A enterotoxin by electroimmunodiffusion are described. As little as 0.01 mug of enterotoxin could be detected. Electroimmunodiffusion was more sensitive than either single gel diffusion or quantitation based on erythemal activity of the toxin in guinea pig skin.