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1.
Food Chem ; 395: 133610, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35810626

RESUMEN

Hormonal active compounds affecting health by altering the hormonal system are present in food. The planar yeast antagonist androgen screen (pYAAS) bioassay is a powerful tool to detect individual hormonal active compounds in complex samples separated by high-performance thin-layer chromatography (HPTLC). Previous methods lacked either detection sensitivity or zone sharpness. To overcome diffusion caused by long bioassay incubation on the normal-phase (NP) plate, zone fixation (fix) was achieved with a new polyisobutyl methacrylate coating, leading to enhanced zone sharpness. The exclusion of false-positive antagonists was integrated in the workflow, which allowed the verification (V) of true antagonists, apart from the detection of synergists. With the new multiplex bioassay providing information on 4 activities, 68 different botanicals were screened and hormonal active zones were identified by elution from the bioautogram to orthogonal reversed-phase high performance liquid chromatography with diode array detection and high-resolution mass spectrometry including fragmentation, resulting in the 12D hyphenation NP-HPTLCfix-UV/Vis/FLD-pYAVAS-FLD-heart cut-RP-HPLC-DAD-HRMS/MS.


Asunto(s)
Antagonistas de Andrógenos , Andrógenos , Bioensayo/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos
2.
Phytomedicine ; 103: 154230, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35724612

RESUMEN

BACKGROUND: Phytoestrogens are found in many plants used in traditional medicines. Increasingly, plant extracts (botanicals) are also being added to foods or marketed as dietary supplements. Especially such powder formulations are susceptible to adulteration and falsification, given the global processing chain. To detect estrogen-like compounds in such multicomponent mixtures, non-target screening for hormonally active or endocrine disrupting compounds in plant products is becoming more important. Unfortunately, the current planar yeast estrogen screen (pYES) is prone to zone diffusion on the normal-phase high-performance thin-layer chromatography (NP-HPTLC) plate due to long incubation times in the aqueous bioassay. PURPOSE: The present study aimed to reduce zone diffusion on NP plates, which provides the basis for extending pYES to a multiplex bioassay, offering 4 different biological activity principles, followed by targeted identification of active zones. STUDY DESIGN AND METHODS: The reduction of substance diffusion via a polyisobutyl methacrylate polymer coating was studied. After successful zone fixation (fix), a multiplex bioassay was developed, in which a 17ß-estradiol-strip was applied along each sample track to detect synergists and antagonists (A), and for verification (V), a 4-methyl umbelliferone-strip to exclude false-positives. After multiplex bioassay screening of 68 botanicals, the zones with hormonal activities were heart-cut eluted to reversed-phase high-performance liquid chromatography-diode array detection-high-resolution tandem mass spectrometry (RP-HPLC-DAD-HESI-HRMS/MS). RESULTS: The separated substances were successfully fixed by the chromatogram coating. The zone sharpness (achieved after the bioassay) made it possible to add two strips, the 17ß-estradiol-strip for antagonistic and synergistic, and the 4-methyl umbelliferone-strip for false-positive effect detection, resulting in a multiplex bioassay. Using the 12D hyphenation NP-HPTLCfix-UV/Vis/FLD-pYAVES-FLD heart-cut RP-HPLC-DAD-HESI-HRMS/MS, it was possible to obtain information on estrogens, antiestrogens, false-positives, and synergists, and (tentatively) assign 17 hormonally active compounds, of which only 7 have been known to affect the human estrogen receptor, while another 4 had structural similarity to common phytoestrogens and antiestrogens. CONCLUSIONS: The streamlined 12D hyphenation including a multiplex bioassay has been shown to differentiate hormonal effects, leading to new insights and better understanding. It can generally be used to identify unknown hormonally active compounds in complex samples.


Asunto(s)
Moduladores de los Receptores de Estrógeno , Estrógenos , Bioensayo/métodos , Cromatografía en Capa Delgada/métodos , Estradiol , Humanos , Fitoestrógenos/farmacología , Umbeliferonas , Levaduras
3.
J Chromatogr A ; 1652: 462377, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34271255

RESUMEN

Food testing is of great importance to the food industry and organizations to verify the authenticity claims, to prove the quality of raw materials and products, and to ensure food safety. The market prices of vanilla differed by a factor of about 20 in the last three decades. Therefore the risk of adulteration and counterfeiting of vanilla products is high. Instead of commonly used target analyses and sum parameter assays, a complementary non-target multi-imaging effect-directed screening was developed, which provided a new perspective on the wide range of vanilla product qualities on the market. Planar chromatography was combined with effect-directed assays, and the obtained biological and biochemical profiles of 32 vanilla products from nine different categories revealed a variety of active ingredients. Depending on the region, typical vanilla product profiles and activity patterns were obtained for pods, tinctures, paste (inner part), oleoresin and powders. However, some vanilla products showed additional active compounds and a different intensity pattern. The vanilla product profiles substantially differed from those of vanilla aroma or products containing synthetic vanillin or vanilla-flavored food products. Bioactive compounds of interest were online eluted and further characterized via HPTLC-HRMS, which allowed their tentative assignment. After purchase of the standards, these were successfully confirmed by co-chromatography. Quantification of vanillin across nine different product categories revealed levels ranging from 1 µg/g to 36 mg/g with a mean repeatability of 1.9%. The synthetic ethylvanillin was not detected in the investigated samples in significant concentrations. The assessment of differences in the activity patterns pointed to highly active compounds, which were not detected at UV/Vis/FLD but first via the biological and enzymatic assays. This effect-directed profiling bridges the gap from analytical food chemistry to food toxicology, and thus, makes an important contribution to consumer safety. In the same way, it would accelerate investigations for Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) according to Regulation (EC) No. 1907/2006.


Asunto(s)
Benzaldehídos/análisis , Extractos Vegetales , Vanilla , Benzaldehídos/química , Cromatografía en Capa Delgada , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Vanilla/química
4.
Anal Chem ; 82(12): 5349-56, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20507179

RESUMEN

The strong dependence of separation behavior on ultrathin-layer chromatography (UTLC) stationary phase microstructure motivates continued UTLC plate design optimization efforts. We fabricated 4.6-5.3 mum thick normal phase silica UTLC stationary phases with several types of in-plane macropore anisotropies using the glancing angle deposition (GLAD) approach to engineering nanostructured thin films. The separation behaviors of two new media, isotropic vertical posts and anisotropic bladelike films, were compared to that of anisotropic chevron media. Channel-like structures within the anisotropic media introduced preferential mobile phase flow directions that could be exploited to give separation tracks diagonal to the development direction. Extraction of chromatograms from these angled tracks required the development of a new analytical approach that involved a commercial flatbed film scanner and custom numerical image analysis software. GLAD stationary phase performance was quantified using the Dimethyl Yellow dye separated from a lipophilic dye mixture over migration distances less than approximately 10 mm. The limits of detection were 10 +/- 4 ng for the vertical posts and 11 +/- 3 ng for the bladelike media. We obtained theoretical plate heights that varied with film microstructure between 12 and 28 mum. Unoptimized separation performance was comparable to that of other planar chromatography media. Macropore anisotropies engineered by GLAD may expand the capabilities of future UTLC stationary phases.

5.
J Chromatogr A ; 1588: 137-149, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30665743

RESUMEN

High-performance thin-layer chromatography (HPTLC) methods were developed to determine glycerol, gluconic acid, amino acids and sugars for in-process quality control of wine. Twenty wine samples (Pfalz region, Germany) were diluted with methanol and used for quantitative analysis without any further sample preparation. The developed amino acid method provided quantitative and characteristic fingerprints of wine varieties. The amino acid assignments were verified by HPTLC-MS. The developed gluconic acid method was primarily used to control the threshold, indicating a Botrytis cinerea infection of grapes. However, this method also enabled the detection of further organic acids like malic, tartaric and citric acids. A glycerol method was developed for control of the grape must fermentation (spontaneous/regular) and for fraud detection (glycerol adulteration). The HPTLC results of the sugar contents in the wine samples were similar to those of the well-known Luff-Schoorl method. The combined use of these developed HPTLC methods allowed the fermentation control (e.g., alcoholic and malolactic fermentation) and the monitoring of the grapes' overall health status. Without modification, the HPTLC methods for sugar and amino acid analysis could be transferred to circular micro planar chromatography (µ-PLC), showing its potential and benefits in terms of an inexpensive alternative for wineries and distributors.


Asunto(s)
Cromatografía en Capa Delgada , Análisis de los Alimentos/métodos , Control de Calidad , Vino/análisis , Vino/normas , Botrytis/química , Carbohidratos/análisis , Fermentación , Alemania , Glicerol/análisis , Vitis/química , Vitis/microbiología
6.
Food Chem ; 260: 344-353, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29699678

RESUMEN

Biological and biochemical fingerprints were investigated for the first time for the feasibility of effect-directed classification, and thus, to allow the choice of a distinct beer with regard to beneficial health effects. A high-performance thin-layer chromatography method was newly developed and combined with in situ effect-directed analysis for profiling 50 German beers for multipotent active compounds, and thus, their health-related potential. Discovered multipotent active zones were online eluted and characterized by high resolution mass spectrometry. For example, isoxanthohumol, iso-α-ad/n-humulone or its isomers, desdimethyl-octahydro-isocohumulone and ad/n-humulone were proven as antimicrobial compounds, isoxanthohumol as an acetylcholinesterase inhibitor, and isoxanthohumol and iso-α-ad/n-humulone or its isomers as radical scavengers. Investigating multivariate data analysis of effect-directed fingerprints for the first time, the pattern recognition and classification results showed the power of clustering non-alcoholic beers from other types of beer, or it showed the differentiation of dark and non-alcoholic beers.


Asunto(s)
Cerveza/análisis , Cerveza/clasificación , Análisis de los Alimentos/métodos , Aliivibrio fischeri/efectos de los fármacos , Antiinfecciosos/farmacología , Bacillus subtilis/efectos de los fármacos , Inhibidores de la Colinesterasa/farmacología , Cromatografía en Capa Delgada/métodos , Espectrometría de Masas/métodos , Análisis Multivariante
7.
Food Chem ; 243: 258-268, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29146336

RESUMEN

Decision makers responsible for quality management along the food chain need to reflect on their analytical tools that should ensure quality of food and especially superfood. The "4ables" in target analysis (stable, extractable, separable, detectable) focusing on marker compounds do not cover all relevant information about the sample. On the example of ginger, a streamlined quantitative bioprofiling was developed for effect-directed analysis of 17 commercially available ginger and ginger-containing products via high-performance thin-layer chromatography (HPTLC-UV/Vis/FLD-bioassay). The samples were investigated concerning their active profile as radical scavengers, antimicrobials, estrogen-like activators and acetylcholinesterase/tyrosinase inhibitors. The [6]-gingerol and [6]-shogaol content of the different products ranged 0.2-7.4mg/g and 0.2-3.0mg/g, respectively. Further, multipotent compounds were discovered, characterized, and for example, assigned as [8]- and [10]-gingerol via HPTLC-ESI-HRMS. The developed bioprofiling is a step forward to new analytical methods needed to inform on the true product quality influenced by cultivation, processing, and storage.


Asunto(s)
Cromatografía en Capa Delgada/métodos , Evaluación Preclínica de Medicamentos/métodos , Espectrometría de Masas/métodos , Zingiber officinale/química , Antiinfecciosos/análisis , Antiinfecciosos/farmacología , Bacillus subtilis/efectos de los fármacos , Catecoles/análisis , Inhibidores de la Colinesterasa/análisis , Inhibidores de la Colinesterasa/farmacología , Inhibidores Enzimáticos/análisis , Inhibidores Enzimáticos/farmacología , Alcoholes Grasos/análisis , Análisis de los Alimentos/métodos , Calidad de los Alimentos , Límite de Detección , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/análisis , Extractos Vegetales/química
8.
J Chromatogr A ; 1529: 93-106, 2017 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-29129385

RESUMEN

Quantitative effect-directed profiles of 77 industrially and freshly extracted botanicals like herbs, spices, vegetables and fruits, widely used as food ingredients, dietary supplements or traditional medicine, gave relevant information on their quality. It allows the assessment of food, dietary supplements and phytomedicines with regard to potential health-promoting activities. In contrary to sum parameter assays and targeted analysis, chromatography combined with effect-directed analysis allows fast assignment of single active compounds and evaluation of their contribution to the overall activity, originating from a food or botanical sample. High-performance thin-layer chromatography was hyphenated with UV/Vis/FLD detection and effect-directed analysis, using the 2,2-diphenyl-1-picrylhydrazyl radical, Gram-negative Aliivibrio fischeri, Gram-positive Bacillus subtilis, acetylcholinesterase and tyrosinase assays. Bioactive compounds of interest were eluted using an elution head-based interface and further characterized by electrospray ionization (high-resolution) mass spectrometry. This highly streamlined workflow resulted in a hyphenated HPTLC-UV/Vis/FLD-EDA-ESI+/ESI--(HR)MS method. The excellent quantification power of the method was shown on three compounds. For rosmarinic acid, contents ranged from 4.5mg/g (rooibos) to 32.6mg/g (rosemary), for kaempferol-3-glucoside from 0.6mg/g (caraway) to 4.4mg/g (wine leaves), and for quercetin-3-glucoside from 1.1mg/g (hawthorn leaves) to 17.7mg/g (thyme). Three mean repeatabilities (%RSD) over 18 quantifications for the three compounds were ≤2.2% and the mean intermediate precision over three different days (%RSD, n=3) was 5.2%.


Asunto(s)
Técnicas de Química Analítica/métodos , Cromatografía en Capa Delgada , Extractos Vegetales/análisis , Espectrometría de Masa por Ionización de Electrospray , Aliivibrio fischeri/efectos de los fármacos , Bacillus subtilis/efectos de los fármacos , Bioensayo , Compuestos de Bifenilo/química , Técnicas de Química Analítica/normas , Cromatografía Líquida de Alta Presión , Frutas/química , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Reproducibilidad de los Resultados , Especias/análisis
9.
Artículo en Inglés | MEDLINE | ID: mdl-28955459

RESUMEN

BACKGROUND: Fungi of the phylum Basidiomycota are well-known to form a broad spectrum of biologically active secondary metabolites, especially low molecular weight compounds such as terpenoids. Hericium erinaceus produces various cyathane type diterpenoids including erinacines. However, no quantitative data and production kinetics have been reported on the biosynthesis of the erinacines C and P in submerged cultures. In the present study, the production of erinacine C was optimized, and the product formation kinetics as well as the antimicrobial activity were studied by high-performance liquid chromatography (HPLC), high-performance thin-layer chromatography (HPTLC) and direct bioautography. RESULTS: Oatmeal and Edamin® K were identified to be crucial media components for an efficient production of erinacine C. The highest concentrations of erinacine C were obtained in the optimized culture medium on the 9th culture day (approximately 260 mg L-1). The production of erinacine P was strongly time dependent. The maximum concentration of erinacine P of 184 mg L-1 was observed on the third culture day. Afterwards, the concentrations of erinacine P decreased while the concentrations of erinacine C steadily increased. Comparable results were obtained by HPTLC with UV detection and HPLC with diode-array detection (DAD) analyses. Direct bioautography allowed for an additional analysis of the antimicrobial activity of the secondary metabolites. CONCLUSIONS: The C and N sources oatmeal and Edamin® K induced the formation of erinacine C. Detailed product formation kinetics of the erinacines C and P have been reported for the first time. HPTLC combined with the Aliivibrio fischeri bioassay allowed for an instant detection of cyathane diterpenoids in crude extracts and for an evaluation of the antimicrobial activity of the secondary metabolites directly on the plate.

10.
J Chromatogr A ; 1426: 209-19, 2015 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-26643726

RESUMEN

A healthy diet is an important factor in a healthy lifestyle that is becoming increasingly important in today's society. The fruits of European elder (Sambucus nigra L.) are a rich source of bioactive compounds like anthocyanins. In this study, dried and fresh fruits of four cultivated and six wild growing plants were investigated for their anthocyanin pattern and content as well as their bioactive compounds. After separation on HPTLC plates silica gel 60 F254 with a mixture of ethyl acetate, 2-butanone, formic acid and water, the plates were quantitatively evaluated by densitometry and also subjected to various (bio)assays to investigate the samples for compounds acting as radical-scavengers, antimicrobials, estrogens, and acetylcholinesterase or tyrosinase inhibitors. The mean contents for the two most abundant anthocyanins in European elderberries, confirmed by HPTLC-ESI-MS, ranged from 159 to 647mg/100g in fresh and from 166 to 2764mg/100g in dried fruits for cyanidin-3-sambubioside, and from 112 to 521mg/100g in fresh and 95 to 226mg/100g in dried fruits for cyanidin-3-glucoside. Additionally, the anthocyanin content was higher in berries of cultivars than of wild growing plants. The anthocyanins' radical scavenging activity and antimicrobial effect against Aliivibrio fischeri were confirmed. Further, a radical scavenging compound affecting A. fischeri and acting as acetylcholinesterase inhibitor was tentatively assigned by its protonated molecule at m/z 456 as either ursolic or oleanolic acid by HPTLC-ESI-MS. HPTLC hyphenated with bioassays and mass spectrometry was selected as method of choice for fingerprinting, pattern recognition, and bioprofiling of elderberry samples as well as quantitation and confirmation of bioactive compounds therein.


Asunto(s)
Antocianinas/análisis , Sambucus/química , Acetilcolinesterasa/química , Aliivibrio fischeri/efectos de los fármacos , Antibacterianos/análisis , Antibacterianos/farmacología , Antioxidantes/análisis , Antioxidantes/farmacología , Bacillus subtilis/efectos de los fármacos , Inhibidores de la Colinesterasa/análisis , Cromatografía en Capa Delgada , Disacáridos/análisis , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/química , Frutas/química , Glucósidos , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray
11.
J Chromatogr A ; 754(1-2): 423-30, 1996 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-8997733

RESUMEN

Planar chromatography is described in the field of water analysis. The principle of automated multiple development (AMD) technique is mentioned, the strategy of the whole procedure which became a German standard is demonstrated and separations of pesticide mixtures, as well as water samples containing pesticides are presented. The suitability of this method was proved for 283 pesticides and the corresponding ISO Standard has been applied for.


Asunto(s)
Cromatografía en Capa Delgada/métodos , Residuos de Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis , Cromatografía Líquida de Alta Presión/métodos , Residuos de Plaguicidas/química , Fosfolípidos/análisis , Espectrofotometría Ultravioleta/métodos
12.
Neurophysiol Clin ; 18(3): 285-90, 1988 Jun.
Artículo en Francés | MEDLINE | ID: mdl-2840562

RESUMEN

A case of Eaton-Lambert myasthenic syndrome associated with inappropriate secretion of antidiuretic hormone is reported. This case included a demyelinizing peripheral neuropathy and was related to a small-cell carcinoma of the lung. Twelve similar cases appeared in the literature, most of them associated with small-cell carcinoma or undifferentiated lung tumors. Etiologic and diagnostic aspects of these syndromes are discussed. When isolated, their causes are various, including the classic context of the paraneoplastic syndromes. Their association is highly suggestive of a lung carcinoma and must enable to make an early diagnosis by use of all possible means of detection.


Asunto(s)
Carcinoma de Células Pequeñas/complicaciones , Enfermedades Desmielinizantes/etiología , Síndrome de Secreción Inadecuada de ADH/etiología , Neoplasias Pulmonares/complicaciones , Miastenia Gravis/etiología , Síndromes Paraneoplásicos , Humanos , Masculino , Persona de Mediana Edad
17.
Int J Infect Dis ; 13(6): 673-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19138546

RESUMEN

BACKGROUND: Understanding the etiologic organism, antimicrobial resistance mechanisms, and transmission of multidrug-resistant tuberculosis (MDR-TB) can be of great value in optimizing strategies to control and prevent its development and transmission. METHODS: One hundred and fifty-five Mycobacterium tuberculosis complex isolates from patients with pulmonary tuberculosis (TB) in Cairo, Egypt were studied. In vitro drug susceptibility testing against rifampin (RIF), isoniazid (INH), streptomycin (SM), ethambutol (EMB), and pyrazinamide (PZA) was performed. Resistance was studied by the standard agar proportion method. Single strand conformation polymorphism (SSCP) and DNA sequence analysis were used to detect mutations in the genes that encode resistance to rpoB, katG, rpsL, and embB. RESULTS: Among 155 consecutive M. tuberculosis isolates, 25 (16.1%) were MDR-TB; 13 of these were from newly diagnosed untreated cases, 12 were from re-treated cases, and none of the MDR-TB isolates had matching IS6110 fingerprints. Among the MDR-TB isolates, rpoB mutations were found in 76% of RIF-resistant isolates, katG mutations were found in 47.1% of INH-resistant isolates, rpsL mutations were found in 55.6% of SM-resistant isolates, and embB mutations were found in 36.4% of EMB-resistant isolates. CONCLUSIONS: No major differences were found in the frequencies of mutations or types of amino acid substitution between newly diagnosed untreated cases and re-treated cases. The high prevalence of MDR-TB at this hospital underscores the need for continuous monitoring of strains and antimicrobial resistance.


Asunto(s)
Antituberculosos/farmacología , Farmacorresistencia Bacteriana/genética , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Pulmonar/epidemiología , Proteínas Bacterianas/genética , Egipto/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/genética , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADN , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/microbiología
18.
Epidemiol Infect ; 137(3): 389-95, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19021923

RESUMEN

An outbreak of haemolytic uraemic syndrome (HUS) among children caused by infection with sorbitol-fermenting enterohaemorrhagic Escherichia coli O157:H- (SF EHEC O157:H-) occurred in Germany in 2002. This pathogen has caused several outbreaks so far, yet its reservoir and routes of transmission remain unknown. SF EHEC O157:H- is easily missed as most laboratory protocols target the more common sorbitol non-fermenting strains. We performed active case-finding, extensive exploratory interviews and a case-control study. Clinical and environmental samples were screened for SF EHEC O157:H- and the isolates were subtyped by pulsed-field gel electrophoresis. We identified 38 case-patients in 11 federal states. Four case-patients died during the acute phase (case-fatality ratio 11%). The case-control study could not identify a single vehicle or source. Further studies are necessary to identify the pathogen's reservoir(s). Stool samples of patients with HUS should be tested with an adequate microbiological set-up to quickly identify SF EHEC O157:H-.


Asunto(s)
Brotes de Enfermedades , Escherichia coli O157/aislamiento & purificación , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Síndrome Hemolítico-Urémico/epidemiología , Síndrome Hemolítico-Urémico/microbiología , Estudios de Casos y Controles , Niño , Preescolar , Escherichia coli O157/metabolismo , Femenino , Contaminación de Alimentos , Alemania/epidemiología , Humanos , Lactante , Modelos Logísticos , Masculino , Sorbitol/metabolismo
19.
Gesundheitswesen ; 67(12): 858-61, 2005 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-16379048

RESUMEN

Shiga toxin producing Escherichia coli (STEC) in sewage influent into surface water are a potential source of human infections with STEC. Eight sewage treatment plants in Bavaria, Germany, were sampled at regular intervals from 2003 to 2004 in order to estimate STEC load and quantify risk factors. 95 of 378 samples (25 %) were tested positive for stx1and/or stx2 with PCR after enrichment culture. STEC elimination after treatment was 44 %. The following risk factors were analysed with logistic regression: location of sewage plant (rural vs. urban), treatment plant technology (two stage vs. three stage treatment) and sampling location (sewage input vs. sewage output). Rural plants had odds-ratios of 1,7 (95 % CI 1.03 - 2.69; p = 0.038) for a positive stx1 and/ or stx2 PCR result, sampling at sewage input of 2.1 (95 %CI 1.28 - 3.36; p = 0.003) and three stage plants of 1.51 (95 % CI 0.94 - 2.44; p = 0.087, not significant). Sampling after rain and after dry spells had no impact on STEC abundance (univariate Chi-square test = 0.01; df1; p = 0.920). Rural sewage plants had higher odds of STEC content. The influence of the sewage plant technology on the STEC load requires further clarification.


Asunto(s)
Monitoreo del Ambiente/métodos , Escherichia coli O157/aislamiento & purificación , Residuos Industriales/análisis , Medición de Riesgo/métodos , Aguas del Alcantarillado/microbiología , Toxinas Shiga/biosíntesis , Contaminación del Agua/análisis , Microbiología Ambiental , Monitoreo del Ambiente/estadística & datos numéricos , Monitoreo Epidemiológico , Escherichia coli O157/clasificación , Escherichia coli O157/metabolismo , Alemania/epidemiología , Factores de Riesgo , Toxinas Shiga/aislamiento & purificación
20.
Rev Rhum Mal Osteoartic ; 58(3): 183-6, 1991 Mar.
Artículo en Francés | MEDLINE | ID: mdl-2057691

RESUMEN

The authors report four cases of hypercalcemia occurring during the course of carcinoma of the prostate. This association is rare (less than twenty published cases) though not exceptional, carcinoma of the prostate accounting for almost 4 per cent of causes of malignant hypercalcemia. This generally involves advanced and metastatic forms, at the terminal phase, but cases of regression after hormone therapy have been reported. The histological type of the tumour is unusual in one case in two (anaplastic or carcinoid). The mechanism of this hypercalcemia is humoral, probably by secretion of a parathormone-like peptide, but which has not yet been fully elucidated.


Asunto(s)
Adenocarcinoma/complicaciones , Carcinoma de Células Transicionales/complicaciones , Hipercalcemia/etiología , Neoplasias de la Próstata/complicaciones , Anciano , Humanos , Masculino , Persona de Mediana Edad
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