RESUMEN
Three-dimensional (3D) imaging and post processing are common tasks used daily in many disciplines. The purpose of this article is to review the new postprocessing tools available. Although 3D imaging can be applied to all anatomical regions and used with all imaging techniques, its most varied and relevant applications are found with computed tomography (CT) data in musculoskeletal imaging. These new applications include global illumination rendering (GIR), unfolded rib reformations, subtracted CT angiography for bone analysis, dynamic studies, temporal subtraction and image fusion. In all of these tasks, registration and segmentation are two basic processes that affect the quality of the results. GIR simulates the complete interaction of photons with the scanned object, providing photorealistic volume rendering. Reformations to unfold the rib cage allow more accurate and faster diagnosis of rib lesions. Dynamic CT can be applied to cinematic joint evaluations a well as to perfusion and angiographic studies. Finally, more traditional techniques, such as minimum intensity projection, might find new applications for bone evaluation with the advent of ultra-high-resolution CT scanners. These tools can be used synergistically to provide morphologic, topographic and functional information and increase the versatility of CT.
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Imagenología Tridimensional , Enfermedades Musculoesqueléticas , Angiografía por Tomografía Computarizada , Humanos , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
Preventing foodborne pathogen contamination of raw fruit and vegetables in the field is critically important for public health. Specifically, it involves preventing faecal deposit by wildlife or domestic animals in fields of crops and kitchen gardens. The present study aims to identify the drivers of fox, dog and cat faecal deposits in kitchen gardens in order to mitigate the risk of contamination of raw produce with parasites shed in carnivore faeces. The focus was on Echinococcus multilocularis, ranked highest in the importance of foodborne parasites in Europe, but attention was also paid to other parasites of major concern - Toxoplasma gondii and Toxocara spp. During the winters of 2014 to 2016, faecal samples were collected from 192 kitchen gardens located in north-eastern France. From these samples, 77% contained scat of carnivores. Molecular analyses revealed that 59% of the 1016 faeces collected were from cats, 31% from foxes, and 10% from dogs. The ease of accessibility to kitchen gardens, the presence of food in the vicinity, and the composition of the surrounding vegetation were used to explain the distribution of fox and cat faeces. Generalized Linear Mixed Effects modelling showed that: i) fencing was not efficient in reducing cat faecal deposits, but drastically decreases those of foxes; ii) the abundance of Microtus sp. indicates a reason for the presence of both fox and cat faecal deposits, iii) the abundance of Arvicola terrestris, the proximity of fruit trees or farms and the predominance of forest and grassland around the village are all drivers of fox faecal deposits. These results point to the importance of fencing around kitchen gardens located in E. multilocularis endemic areas, particularly those surrounded by forest and grassland or close to fruit trees or farms.
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The mammalian gastrointestinal tract can harbor both beneficial commensal bacteria important for host health, but also pathogenic bacteria capable of intestinal damage. It is therefore important that the host immune system mount the appropriate immune response to these divergent groups of bacteria-promoting tolerance in response to commensal bacteria and sterilizing immunity in response to pathogenic bacteria. Failure to induce tolerance to commensal bacteria may underlie immune-mediated diseases such as human inflammatory bowel disease. At homeostasis, regulatory T (Treg) cells are a key component of the tolerogenic response by adaptive immunity. This review examines the mechanisms by which intestinal bacteria influence colonic T-cells and B-cell immunoglobulin A (IgA) induction, with an emphasis on Treg cells and the role of antigen-specificity in these processes. In addition to discussing key primary literature, this review highlights current controversies and important future directions.
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Antígenos Bacterianos/inmunología , Linfocitos B/inmunología , Colon/inmunología , Microbioma Gastrointestinal/inmunología , Linfocitos T Reguladores/inmunología , Animales , Colon/microbiología , Homeostasis , Humanos , Inmunidad Celular , Inmunoglobulina A/metabolismo , Simbiosis , Especificidad del Receptor de Antígeno de Linfocitos TRESUMEN
The use of membrane technology for municipal wastewater reuse is growing in importance worldwide as water becomes increasingly scarce. A review of nine membrane technology-based water reuse plants from across the world has been conducted to provide an insight into the trends in design and operation of these plants, and elucidate the impact of key water quality and other determinants. Data reveal a number of common elements, such as the design flux for the reverse osmosis membrane, as well as a number of other trends. The microfiltration/ultrafiltration (MF/UF) backwash interval appears to correlate better with feed water temperature than turbidity or total suspended solids, whereas chemical cleaning requirements are more dependent on plant operating parameters and water quality. There is some indication that the MF/UF pore size influences the filtrate turbidity (and silt density index) and so downstream reverse osmosis fouling and cleaning. Finally, specific energy demand (SED) values vary widely, from 0.8 to 2.3 kWh m(-3) permeate. Whilst the SED for the MF/UF process follows the flux, the overall energy demand shows no apparent dependence on the dissolved solids concentration or other feed water quality determinants. This range of energy demand amounts to 25-70% of the energy demand for seawater desalination.
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Membranas Artificiales , Evaluación de la Tecnología Biomédica , Ultrafiltración/instrumentación , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Ultrafiltración/métodos , Contaminantes Químicos del Agua/química , Purificación del Agua/métodosRESUMEN
A range of commercial granular activated carbon (GAC) media have been assessed as pretreatment technologies for a downstream microfiltration (MF) process. Media were assessed on the basis of reduction in both organic matter and turbidity, since these are known to cause fouling in MF membranes. Isotherm adsorption analysis through jar testing with supplementary column trials revealed a wide variation between the different adsorbent materials with regard to organics removal and adsorption kinetics. Comparison with previous work using powdered activated carbon (PAC) revealed that for organic removal above 60% the use of GAC media incurs a significantly lower carbon usage rate than PAC. All GACs tested achieved a minimum of 80% turbidity removal. This combination of turbidity and organic removal suggests that GAC would be expected to provide a significant reduction in fouling of a downstream MF process with improved product water quality.
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Carbón Orgánico/química , Compuestos Orgánicos/aislamiento & purificación , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del AguaRESUMEN
Concern over prospective levels of N-nitrosodimethylamine (NDMA) in waters has increased in recent years due to its disinfection byproduct formation potential from chloramination. It has been mooted that this is promoted by organic precursors from municipal wastewaters, such that there is a more significant risk of excessive levels in water reuse applications. Experiments conducted on chloramination and chlorination of secondary wastewater have confirmed that that significant NDMA formation arises only from chloramination, with its concentration varying with test conditions used. A full factor analysis revealed all parameters studied (temperature, pH, monochloramine dose and contact time), both individually and synergistically, to have a statistically significant impact on NDMA formation with contact time being the most important. At raw water temperatures below 10 °C, the NDMA concentration can be minimised to below the 10 ng L(-1) threshold by not exceeding a monochloramine dose of 2 mg L(-1) as Cl(2). However, at higher water temperatures other measures are required to suppress NDMA formation, such as reducing the contact time (which could prove impractical in most applications) or maintaining a pH below 6. Further trials are required to fully develop the operating envelope to ensure NDMA concentrations do not exceed the 10 ng L(-1) threshold, or else to identify effective pretreatment methods for removing the NDMA precursors.
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Desinfectantes/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Dimetilnitrosamina/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
An automatic backflush pre-filter used for pre-treatment for secondary wastewater re-use was evaluated and optimised at two different mesh sizes over an 18 month period. The filter was initially run with a 500 microm rating mesh size, as recommended by the supplier of the downstream membrane filtration process, and then at 100 microm to investigate any change in water quality produced and associated improved membrane performance. With the 500 microm mesh in place, the filter fouling rate was low and a backflush was initiated every 3.5 h. For the 100 microm mesh the fouling rate was extremely rapid. Fouling was found to be caused by reverse side blockage of the pre-filter due to biofilm growth, and not by improved solids capture; there was no improvement in water quality with the smaller mesh size, since particle unloading from the biofilm took place. The pre-filter fouling rate was found to be related to turbidity. At a turbidity of 5 NTU the filter backflushed around 200 times per day, while at 10 NTU this increased to over 300 times. Further analysis enabled the backflush water volume to be decreased by reducing the backflush duration and increasing the backflush cycle time (i.e. the time between backflushes).
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Filtración/métodos , Reciclaje/métodos , Purificación del Agua/métodos , Filtración/instrumentación , Membranas Artificiales , Nefelometría y Turbidimetría , Proyectos Piloto , Control de Calidad , Reciclaje/normas , Purificación del Agua/instrumentación , Purificación del Agua/normasRESUMEN
A range of coagulant chemicals and doses, up to 2 mg/L, were trialled on a microfiltration-based indirect potable reuse (IPR) pilot plant to evaluate their impact on membrane reversible and irreversible fouling. Jar tests revealed these doses to have negligible impact on organic matter removal, whilst scoping pilot trials showed them to have a positive impact on fouling rates. Initial trials carried out over a 6-h period suggested that ferric sulphate was the most promising of the coagulants tested with regards to irreversible fouling. Extended five-day trials using ferric sulphate at 0.5 mg/L were conducted at fluxes of 40-50 l/(m(2)h) (LMH). Operation at 50 LMH without coagulant resulted in rapid fouling and a subsequent shortening of the chemical cleaning interval. The addition of the ferric coagulant resulted in a reduction in both reversible and irreversible fouling to those levels experienced at 40 LMH, enabling sustainable operation. The use of low levels of coagulant thus enables the pilot plant to operate at a 25% increased flux, equating to a 20% reduction in membrane area and overall savings of >0.1 p per m(3) for a seven year membrane life.
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Filtración/métodos , Reciclaje/métodos , Eliminación de Residuos Líquidos , Purificación del Agua/métodos , Incrustaciones Biológicas , Costos y Análisis de Costo , Filtración/economía , Floculación , Membranas Artificiales , Nefelometría y Turbidimetría , Sistemas en Línea , Compuestos Orgánicos/aislamiento & purificación , Proyectos Piloto , Reciclaje/economía , Eliminación de Residuos Líquidos/economía , Purificación del Agua/economía , Calidad del AguaRESUMEN
Migration, distal malposition or fracture of self-expanding metallic biliary or esophageal stents rarely occur but may lead to stent dysfunction, mucosal trauma secondary to impaction or friction on the digestive wall. We report our experience of using argon plasma to endoscopically cut three metallic biliary and esophageal self-expanding stents to restore permeability or to treat impaction of the stent after migration, malposition or fracture.
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Endoscopios Gastrointestinales , Esófago , Conducto Hepático Común , Láseres de Gas/uso terapéutico , Falla de Prótesis , Stents/efectos adversos , Anciano , Anciano de 80 o más Años , Aleaciones , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Úlcera Duodenal/etiología , Úlcera Duodenal/terapia , Duodenoscopía , Esófago/cirugía , Migración de Cuerpo Extraño/etiología , Migración de Cuerpo Extraño/terapia , Gastroscopía , Conducto Hepático Común/cirugía , Humanos , Masculino , Diseño de Prótesis , Siliconas , Resultado del TratamientoRESUMEN
A 60-year-old man presented an oesophageal transmural necrosis fistulised in the trachea following curative photodynamic therapy (PDT) for a superficial recurrence of an oesophageal carcinoma, initially treated by radiochemotherapy. Two stents, a tracheal and an oesophageal one, were placed. Eight months later the patient is in complete remission with only mild swallowing problems. This complication, although unusual, has already been described by other teams with the association of radiochemotherapy and PDT. The present case study suggests that illumination dose should be lowered in this indication.
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Neoplasias Esofágicas/terapia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Fotoquimioterapia/efectos adversos , Fístula Traqueoesofágica/etiología , Carcinoma de Células Escamosas/terapia , Quimioterapia Adyuvante , Éter de Dihematoporfirina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Necrosis , Fármacos Fotosensibilizantes/efectos adversos , Radioterapia Adyuvante , Stents , Fístula Traqueoesofágica/patología , Fístula Traqueoesofágica/cirugíaRESUMEN
The metabolism of dipropyl disulphide (DPDS), a sulphur compound from onion, was investigated in vivo in the rat. A single dose (200 mg kg(-1)) was administered by gastric intubation and the time courses of DPDS and its metabolites were followed over 48 h by gas chromatography coupled with mass spectrometry in the stomach, intestine, liver, and blood. DPDS was detected in the stomach where it was transformed into propyl mercaptan, whereas the liver contained only traces of DPDS and none at all in the other examined organs. The metabolites methylpropyl sulphide, methylpropyl sulphoxide (MPSO), and methylpropyl sulphone (MPSO2) were sequentially formed in the liver. The route of elimination from the liver seemed to be mainly via the blood. The bile also participated in the excretory process, but only for MPSO2. The pharmacokinetic parameters were determined for all of the above compounds. Whereas the bioavailability of DPDS was very low (0.008 h mM), the areas under the curve were higher for the S-oxidized metabolites MPSO and MPSO2, i.e. 9.64 and 24.15 h mM, respectively. The half-lives for DPDS and its metabolites varied between 2.0 and 8.25 h, except for MPSO2, which had a half-life of 29.6 h. MPSO2 was the most abundant and persistent of these metabolites.
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Disulfuros/farmacocinética , Administración Oral , Animales , Cromatografía de Gases , Disulfuros/administración & dosificación , Masculino , Ratas , Ratas Sprague-Dawley , Sulfonas/metabolismo , Sulfóxidos/metabolismo , Distribución TisularRESUMEN
An integrated fixed-film activated sludge (IFAS) pilot plant and a moving bed biofilm reactor coupled with an activated sludge process (MBBR/AS) were operated under different temperatures, carbon loadings and solids retention times (SRTs). These two types of hybrid systems were compared, focusing on the nitrification capacity and the nitrifiers population of the media and suspended biomass alongside other process performances such as carbonaceous and total nitrogen (TN) removal rates. At high temperatures and loadings rates, both processes were fully nitrifying and achieved similarly high carbonaceous removal rates. However, under these conditions, the IFAS configuration performed better in terms of TN removal. Lower temperatures and carbon loadings led to lower carbonaceous removal rates for the MBBR/AS configuration, whereas the IFAS configuration was not affected. However, the nitrification capacity of the IFAS process decreased significantly under these conditions and the MBBR/AS process was more robust in terms of nitrification. Ammonia oxidising bacteria (AOB) and nitrite oxidising bacteria (NOB) population counts accurately reflected the changes in nitrification capacity. However, significantly less NOBs than AOBs were observed, without noticeable nitrite accumulation, suggesting that the characterisation method used was not as sensitive for NOBs and/or that the NOBs had a higher activity than the AOBs.
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Nitrógeno/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Amoníaco/metabolismo , Bacterias/metabolismo , Reactores Biológicos , Nitritos/metabolismo , Nitrógeno/metabolismo , Compuestos de Amonio Cuaternario/aislamiento & purificación , Compuestos de Amonio Cuaternario/metabolismo , Aguas del Alcantarillado , Contaminantes Químicos del Agua/metabolismoRESUMEN
Ten biomass samples from both municipal and industrial pilot and full scale submerged membrane bioreactors (MBRs) with mixed liquor suspended solids concentrations (MLSS) ranging from 7.2 to 30.2g L(-1) were studied at six air-flow rates (0.7, 1.3, 2.3, 3, 4.4 and 6m(3)m(-3)h(-1)). Statistical analyses were applied to identify the relative impacts of the various bulk biomass characteristics on oxygen transfer. Of the biomass characteristics studied, only solids concentration (correlated with viscosity), the carbohydrate fraction of the EPS (EPS(c)) and the chemical oxygen demand (COD) concentration of the SMP (SMP(COD)) were found to affect the oxygen transfer parameters k(L)a(20) (the oxygen transfer coefficient) and alpha-factor. The relative influence on k(L)a(20) was MLSS>aeration>EPS(c)>SMP(COD) and on alpha-factor was MLSS>SMP(COD)>EPS(c)>aeration. Both k(L)a(20) and alpha-factor increased with increasing aeration and EPS(c) and decreased with increasing MLSS and SMP(COD). MLSS was found to be the main parameter controlling the oxygen transfer.
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Reactores Biológicos , Oxígeno/metabolismo , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos , Biomasa , Filtración/instrumentación , Aguas del Alcantarillado/microbiología , Viscosidad , Purificación del AguaRESUMEN
BACKGROUND: A high prevalence (52%) of hyperhomocysteinemia is observed in Crohn disease (CD), however it is not well documented in ulcerative colitis (UC). Furthermore, in the different works studying hyperhomocysteinemia the associated factors are different. AIM: Prospective evaluation of hyperhomocysteinemia in inflammatory bowel disease (IBD) patients, of the risk factors and the determination of a potential risk of colorectal carcinoma in case of hyperhomocysteinemia. PATIENTS AND METHODS: IBD patients followed in our department were prospectively recruited between November 2003-September 2004. To be included patients should have passed a coloscopy in the two years. Patients with kidney failure or drugs supposed, to interfere with homocystéine metabolism (folates, vitamin B12, methotrexate) were excluded from the study. The following parameters were analysed: age, sex, clinical activity indexes (CDAI for Crohn disease and CAI for ulcerative colitis), length-extent and type of the disease (CD or UC), smoking, plasma homocystein concentration, folates and vitamin B12. RESULTS: Eighty-one patients (60 CD, 21 UC, mean age 43.8 +/- 17.3) were included, 30 had an active disease at inclusion and 16 were smokers. The prevalence of high homocystein concentration was 55.6%. In univariate analysis a low rate of folates was the only risk factor for a high homocystein concentration (74 vs. 52.8%; P = 0.018). Smoking was almost an associated factor. In multivariate analysis, a low rate of folate was the only risk factor of hyperhomocysteinemia, OR = 3.59 [1.27-10.17]. Five endoscopic lesions considered as precancerous were described; these patients had all a hyperhomocysteinemia. CONCLUSION: The prevalence of hyperhomocysteinemia is high in UC and in CD. A low folate rate is the only risk factor observed in our study. There is a possible link between colorectal cancer and hyperhomocysteinemia. A high Plasma homocystein concentration must be search in inflammatory bowel disease patients and a substitutive treatment of folates and vitamin B12 is necessary in case of hyperhomocysteinemia.
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Hiperhomocisteinemia/epidemiología , Hiperhomocisteinemia/etiología , Enfermedades Inflamatorias del Intestino/complicaciones , Adulto , Femenino , Deficiencia de Ácido Fólico/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Estudios Prospectivos , Factores de RiesgoRESUMEN
BACKGROUND: Wild-type RD114 virus is capable of generating syncytia during its replication, and it is believed that cell-free viruses direct the fusion of neighboring cells. The RD114 envelope (Env) that mediates this fusion event is now widely used to pseudotype retroviral and lentiviral vectors in gene therapy. Indeed, vectors pseudotyped with RD114 Env are very efficient to transfer genes into human hematopoietic cells, and they are resistant to human complement inactivation. In this study, we have tested the potential of RD114-pseudotyped vectors produced from the FLYRD18 packaging cell line to induce syncytia. METHODS: RD114-pseudotyped vectors produced from the FLYRD18 packaging cells were added on tumor cell lines, and the formation of syncytia was assessed by microscopy after cell fixation and methylene blue staining. The kinetics of syncytium formation was analyzed by time-lapse microscopy. Finally, the cytotoxic effect of RD114-pseudotyped vectors was measured by the MTT assay on tumor cells, and in combination with the TK/GCV strategy. RESULTS: We have found that these vectors were able to mediate cell-to-cell fusion of human tumor cell lines. A few hours after addition of the vector, cells started to aggregate to form syncytia that eventually evolved toward cell death 48 h postinfection. RD114-pseudotyped vectors were very efficient at killing human cancer cells, and they were also able to enhance dramatically the cytotoxic effect of the TK/GCV strategy. CONCLUSIONS: These findings indicate that RD114-pseudotyped vectors used alone, or in combination with a suicide gene therapy approach, have great potential for the treatment of cancer.
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Ganciclovir/uso terapéutico , Terapia Genética , Vectores Genéticos , Células Gigantes/patología , Neoplasias/patología , Retroviridae/genética , Timidina Quinasa/genética , Efecto Espectador , Línea Celular Tumoral , Proliferación Celular , Humanos , Neoplasias/enzimologíaRESUMEN
Exogenous n-3 polyunsaturated fatty acids (PUFA) and specially docosahexaenoic acid (DHA) have been previously reported to potentiate the efficacy of anticancer agents that generate an oxidative stress, such as anthracyclines, by enhancing the susceptibility of cell membranes to lipid peroxidation. Since lipid peroxidation has also been suggested to mediate anthracycline-induced heart failure, we designed a study aimed at investigating whether a DHA-enriched diet coupled with controlled oxidative conditions prevents or aggravates this serious side effect in vivo. Female Sprague-Dawley rats were submitted for at least 3 weeks to diet enriched in DHA, which was provided either as natural oil (sardine oil, experiment 1) or in a purified form (DHASCO, experiment 2). At the same time, to constrain the nutritional oxidative status, the anti-oxidant Vitamin E or the pro-oxidant menadione/sodium ascorbate redox mixture was added. Then, epirubicin was administered weekly at two cumulative doses, 9 mg x kg(-1) (experiment 1) or 15 mg x kg(-1) (experiment 2). Cardiotoxicity was assessed by electrocardiographic (ECG) and hemodynamic measurements, completed with histological examination. Epirubicin-induced dose-dependent mortality, alterations of hemodynamic parameters and histological damages, all features characterizing the occurrence of congestive heart failure. Moreover, the addition of anti- or pro-oxidant did not change the hemodynamics either at the lowest (experiment 1) or the highest dose (experiment 2). Similarly, the ECG measurements and histological examinations did not reveal any difference. DHA was actually incorporated, as evaluated through the adipose tissue fatty acid composition. All these observations indicated that the DHA-enriched diet, placed under controlled oxidative conditions, did not appear to prevent but neither to aggravate epirubicin-induced cardiotoxicity. These findings support the idea that DHA improves the anthracycline therapeutic index.
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Antibióticos Antineoplásicos/efectos adversos , Epirrubicina/efectos adversos , Ácidos Grasos Omega-3 , Cardiopatías/inducido químicamente , Cardiopatías/patología , Tejido Adiposo/metabolismo , Animales , Dieta , Electrocardiografía/efectos de los fármacos , Ácidos Grasos/metabolismo , Pruebas de Función Cardíaca , Miocardio/patología , Oxidación-Reducción , RatasRESUMEN
1. The metabolism of diallyl disulphide was investigated in vitro with rat and human liver cell subfractions and ex vivo with an isolated perfused rat liver. 2. Diallyl disulphide was oxidized to diallylthiosulphinate by rat liver microsomes with an apparent K(m) = 0.86 +/- 0.1 mM and an apparent V(max) = 0.47 +/- 0.12 nmol min(-1) mg(-1) protein (mean +/- SE). Both cytochrome P450 (CYP) and flavin-containing monooxygenases were involved, with CYP2B1/2 and CYP2E1 being the most active CYP enzymes. 3. In rat and man, microsomal oxidation of allylmethyl sulphide to allylmethyl sulphoxide and allylmethyl sulphone also occurred, although at a low rate. Diallyl disulphide was also metabolized to allylglutathione sulphide and allylmercaptan. In addition, diallylthiosulphinate reacted non-enzymatically with glutathione to form allylglutathione sulphide. 4. When an isolated rat liver was perfused with diallyl disulphide, the metabolites allyl mercaptan, allylmethyl sulphide, allylmethyl sulphoxide, allylmethyl sulphone and allylglutathione sulphide were detected primarily within the liver tissue, with only small amounts of metabolites found in the bile and perfusion medium. The pharmacokinetic parameters for diallyl disulphide were t(1/2) = 6.09 min; AUC(0- infinity ) = 4.77 min mmol l(-1); clearance = 34.22 ml min(-1). 5. A scheme for the metabolism of diallyl disulphide in rat and man is proposed.
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Compuestos Alílicos/metabolismo , Disulfuros/metabolismo , Enzimas/metabolismo , Hígado/metabolismo , Anciano , Animales , Área Bajo la Curva , Hidrocarburo de Aril Hidroxilasas/metabolismo , Citocromo P-450 CYP2B1/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Femenino , Humanos , Técnicas In Vitro , Masculino , Microsomas Hepáticos/metabolismo , Persona de Mediana Edad , Oxidación-Reducción , Perfusión , Ratas , Esteroide Hidroxilasas/metabolismo , Compuestos de Azufre/metabolismoRESUMEN
1. Diallyl disulphide (DADS), a compound formed from the organosulphur compounds present in garlic, is known for its anticarcinogenic effects in animal models. 2. The aim was to identify and analyse the metabolites produced in vivo after a single oral administration of 200 mg kg(-1) DADS to rats. The organic sulphur metabolites present in the stomach, liver, plasma and urine were measured by gas chromatography coupled with mass spectrometry over 15 days. 3. Data indicate that DADS is absorbed and transformed into allyl mercaptan, allyl methyl sulphide, allyl methyl sulphoxide (AMSO) and allyl methyl sulphone (AMSO(2)), which are detected throughout the excretion period. Overall, the highest amounts of metabolites were measured 48-72h after the DADS administration. AMSO(2) is the most abundant and persistent of these compounds. The levels of all the sulphur compounds rapidly decline within the first week after administration and disappear during the second week. Only AMSO and AMSO(2) are significantly excreted in urine. 4. These potential metabolites are thought to be active in the target tissues. Our data warrant further studies to check this hypothesis.
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Compuestos Alílicos/metabolismo , Compuestos Alílicos/farmacocinética , Disulfuros/metabolismo , Disulfuros/farmacocinética , Administración Oral , Animales , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Mesilatos/metabolismo , Modelos Químicos , Ratas , Ratas Wistar , Espectroscopía Infrarroja por Transformada de Fourier , Sulfuros/metabolismo , Ácidos Sulfínicos/farmacocinética , Factores de Tiempo , Distribución TisularRESUMEN
Thyroid hormones are of considerable importance for vertebrate reproductive function and during development. To further assess the role of these compounds in this capacity, we examined the expression pattern of the type 2 iodothyronine deiodinase (D2), which converts T(4) to the more active hormone T(3), in the rat uterus in both the nonpregnant and the pregnant state. D2 activity was identified as the predominant, if not only, 5'-deiodinase in the nonpregnant rat uterus. The expression of D2 messenger RNA was located by in situ hybridization to the endometrial stromal cells, where the signal was particularly enriched in the region adjacent to the epithelial cells of the uterine lumen. During pregnancy, D2 activity increased, peaking on day 17 of gestation (embryonic day 17). At that time, uterine D2 activity exceeded that in the placenta, as well as that in the fetal tissues. In the earlier stages of pregnancy before placental formation (e.g. embryonic days 10-11), D2 messenger RNA in the rat uterus was located outside the decidual tissue, which was observed, as in previous studies, to highly express the inactivating type 3 deiodinase. In summary, the rat uterus, particularly during pregnancy, seems to be a site of active thyroid hormone metabolism, presumably designed to maintain the optimal thyroid hormone environment for both the fetus and the maternal uterine tissue.
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Yoduro Peroxidasa/biosíntesis , Isoenzimas/biosíntesis , Preñez/metabolismo , Útero/enzimología , Animales , Inducción Enzimática , Femenino , Hibridación in Situ , Yoduro Peroxidasa/genética , Masculino , Embarazo , ARN Mensajero/análisis , RatasRESUMEN
OBJECTIVE: To assess the recent incidence of ectopic pregnancy (EP) in France (1992-1997) and to relate this incidence to trends in risk factors and use of contraception. DESIGN: Population register-based study. SETTING: Auvergne EP register (central France). PATIENT(S): Women aged 15-44 years with EP in the Auvergne region. MAIN OUTCOME MEASURE(S): Rates of EP, frequencies of exposure to risk factors, and sales of contraceptive methods in 1992-1997. RESULT(S): The overall EP rate decreased 13.7%, from 96.4 per 100,000 women aged 15-44 in 1992 to 83.2 per 100,000 in 1997. The rate of EP associated with reproductive failure remained stable, but the rate of EP associated with contraceptive failure (mostly intrauterine device failure) decreased 26.6%. The trends in the prevalence of the main risk factors for EP and sales of contraceptive methods are concordant with the changes in EP rates: Risk factor prevalence did not change over time, but intrauterine device sales in the area declined in parallel. CONCLUSION(S): The rates of EP as the result of contraceptive failure and as a result of reproductive failure evolve differently in the population and should not be confused in epidemiologic studies. This finding, along with published evidence that the two types of EP have different risk factors, location, prognosis, and perception by women, indicates that they are two distinct clinical entities possibly requiring different management.