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1.
Mycotoxin Res ; 36(2): 213-223, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31960350

RESUMEN

A 10-week feeding experiment was carried out examining the effects of deoxynivalenol (DON)-contaminated maize treated with different sodium sulphite (SoS) concentrations on performance, health and DON-plasma concentrations in fattening pigs. Two maize batches were used: background-contaminated (CON, 0.73 mg/kg maize) and Fusarium-toxin contaminated (DON, 44.45 mg/kg maize) maize. Both were wet preserved at 20% moisture content, with one of three (0.0, 2.5, 5.0 g/kg maize) sodium sulphite concentrations and propionic acid (15%). Each maize batch was then mixed into a barley-wheat-based diet at a proportion of 10%, resulting in the following 6 feeding groups: CON- (CON + 0.0 g SoS/kg maize), CON2.5 (CON + 2.5 g SoS/kg maize), CON5.0 (CON + 5.0 g SoS/kg maize), DON- (DON + 0.0 g SoS/kg maize), DON2.5 (DON + 2.5 g SoS/kg maize) and DON5.0 (DON + 5.0 g SoS/kg maize). Dietary DON concentration was reduced by ~ 36% in group DON2.5 and ~ 63% in group DON5.0. There was no impact on ZEN concentration in the diets due to SoS treatment. Pigs receiving diet DON- showed markedly lower feed intake (FI) compared to those fed the control diets. With SoS-treatment of maize, FI of pigs fed the DON diet (DON5.0: 3.35 kg/d) were comparable to that control (CON-: 3.30 kg/day), and these effects were also reflected in live weight gain. There were some effects of SoS, DON or their interaction on serum urea, cholesterol and albumin, but always within the physiological range and thus likely negligible. SoS wet preservation of Fusarium-toxin contaminated maize successfully detoxified DON to its innocuous sulfonates, thus restoring impaired performance in fatteners.


Asunto(s)
Alimentación Animal/análisis , Contaminación de Alimentos/prevención & control , Sulfitos/farmacología , Tricotecenos/análisis , Aumento de Peso/efectos de los fármacos , Albúminas/análisis , Crianza de Animales Domésticos , Animales , Colesterol/sangre , Fusarium/patogenicidad , Porcinos , Urea/sangre , Zea mays/química
3.
Eur Biophys J ; 33(1): 50-8, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-13680210

RESUMEN

The entrapment of enzymes, drugs, cells or tissue fragments in alginates cross-linked with Ca(2+) or Ba(2+) has great potential in basic research, biotechnology and medicine. The swelling properties and, in turn, the mechanical stability are key factors in designing an optimally cross-linked hydrogel matrix. These parameters depend critically on the cross-linking process and seemingly minor modifications in manufacture have a large impact. Thus, sensitive and non-invasive tools are required to determine the spatial homogeneity and efficacy of the cross-linking process. Here, we show for alginate microcapsules (between 400 microm and 600 microm in diameter) that advanced (1)H NMR imaging, along with paramagnetic Cu(2+) as contrast agent, can be used to validate the cross-linking process. Two- and three-dimensional images and maps of the spin-lattice relaxation time T(1) of Ba(2+) cross-linked microcapsules exposed to external Cu(2+) yielded qualitative as well as quantitative information about the accumulation of Cu(2+) within and removal from microcapsules upon washing with Cu(2+) free saline solution. The use of Cu(2+) (having a slightly higher affinity constant to alginate than Ba(2+)) for gelling gave a complementary insight into the spatial homogeneity of the cross-linking process together with information about the mechanical stability of the microcapsules. The potential of this technique was demonstrated for alginates extracted from two different algal sources and cross-linked either externally by the conventional air-jet dropping method or internally by the "crystal gun" method.


Asunto(s)
Alginatos/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Alginatos/ultraestructura , Bario , Fenómenos Biofísicos , Biofisica , Cápsulas , Medios de Contraste , Cobre , Reactivos de Enlaces Cruzados , Geles , Imagen por Resonancia Magnética
4.
Biomaterials ; 24(12): 2083-96, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12628829

RESUMEN

Cross-linked alginate microcapsules of sufficient mechanical strength can immunoisolate cells for the long-term treatment of hormone and other deficiency diseases in human beings. However, gelation of alginate by external Ba(2+) (or other divalent cations) produces non-homogeneous cross-linking of the polymeric mannuronic (M) and guluronic (G) acid chains. The stability of such microcapsules is rather limited. Here, we show that homogeneous cross-linking can be achieved by injecting BaCl(2) crystals into alginate droplets before they come into contact with external BaCl(2). The high effectiveness of this crystal gun method is demonstrated by confocal laser scanning microscopy and by advanced nuclear magnetic resonance imaging. Both techniques gave clear-cut evidence that homogeneous cross-linkage throughout the microcapsule is only obtained with simultaneous internal and external gelation. Atomic force microscopy showed a very smooth surface topography for microcapsules made by the crystal gun method, provided that excess Ba(2+) ions were removed immediately after gelation. In vitro experiments showed greatly suppressed swelling for crystal gun microcapsules. Even alginate extracted from Lessonia nigrescens (highly biocompatible) yielded microcapsules with long-term mechanical stability not hitherto possible. Encapsulation of rat islets, human monoclonal antibodies secreting hybridoma cells and murine mesenchymal stem cells transfected with cDNA encoding for bone morphogenetic protein (BMP-4) revealed that injection of BaCl(2) crystals has no adverse side effects on cell viability and function. However, the release of low-molecular weight factors (such as insulin) may be delayed when using alginate concentrations in the usual range.


Asunto(s)
Alginatos/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Espectroscopía de Resonancia Magnética/métodos , Microscopía de Fuerza Atómica/métodos , Microscopía Confocal/métodos , Bario/química , Compuestos de Bario/farmacología , Proteína Morfogenética Ósea 4 , Proteínas Morfogenéticas Óseas/química , Cationes , Línea Celular Tumoral , Supervivencia Celular , Cloruros/farmacología , Reactivos de Enlaces Cruzados/farmacología , ADN Complementario/metabolismo , Humanos , Insulina/química , Iones , Transfección
5.
J Virol ; 72(12): 10083-92, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9811748

RESUMEN

Regulation of the human papillomavirus type 16 (HPV-16) E6 promoter is a complex process in which transcriptional repression as well as activation plays an important role. Here, we identify a negative regulatory element that in the context of a continuous long control region fragment overcomes the activation of the HPV-16 enhancer. This silencing element, which we have termed a PSM (papillomavirus silencing motif), consists of two copies of the sequence 5'-TAYAATAAT-3' that overlap the origin of replication. Each copy of this 9-bp sequence binds the same unknown cellular factor, which we refer to as PSM-BP (PSM binding protein). Both copies of the binding sequence are required for transcriptional repression, and we provide evidence that suggests that this particular organization results in the stabilization of a PSM-BP dimer. The silencing motif, while functioning in either orientation, showed a positional requirement between the enhancer and the promoter. Experiments with both a heterologous enhancer and a promoter also demonstrated a general ability of this element to function as a transcriptional silencer in non-HPV systems. Our findings provide an important addition to our understanding of HPV-16 gene regulation and an interesting model for the study of transcriptional repression.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Papillomaviridae/genética , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Bases , Sitios de Unión/genética , Células Cultivadas , ADN Viral/genética , ADN Viral/metabolismo , Factores de Unión al ADN Específico de las Células Eritroides , Regulación Viral de la Expresión Génica , Genes Virales , Células HeLa , Humanos , Proteínas Oncogénicas Virales/genética , Papillomaviridae/metabolismo , Proteínas E7 de Papillomavirus , Regiones Promotoras Genéticas , Origen de Réplica , Factor de Transcripción YY1
6.
Rehabilitation (Stuttg) ; 36(1): 26-33, 1997 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-9213870

RESUMEN

Given a growing number of elderly people and the related consequences for the health care system, such as increasing numbers of persons with chronic diseases or in need of long-term nursing care, the present rehabilitation system must be extended and new services be introduced. Hospitals in Cologne report that an average 48% of their geriatric patients are in need of rehabilitation measures. Taking into account the patients' willingness and capacity to undergo rehabilitation treatment, the figure reduces to 30%. Based on the number of geriatric patients treated in hospital each year, rehabilitation facilities for 15416 geriatric patients a year have to be provided. About two thirds of the patients require continued hospital treatment after the acute phase. Obviously, these treatments are not only performed in the geriatric departments of the hospitals, as only 161 geriatric beds are available in Cologne. One third of the patients could be taken care of on a partial hospitalization or outpatient basis after the acute phase. Thus, limiting a patient's length of stay in hospital could have a cost-containment effect. As partial hospitalization and outpatient rehabilitation facilities are lacking, the Cologne "Geriatrics" study group has developed a concept of "integrated geriatric rehabilitation", suggesting the establishment of mobile rehabilitation teams. The concept aims at developing a cooperative network linking outpatient with partial hospitalization and inpatient services, and including the physicians at community level.


Asunto(s)
Servicios de Salud para Ancianos/provisión & distribución , Rehabilitación , Anciano , Atención Ambulatoria , Control de Costos , Prestación Integrada de Atención de Salud , Femenino , Alemania , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Hospitalización , Humanos , Tiempo de Internación , Cuidados a Largo Plazo , Masculino , Unidades Móviles de Salud , Rehabilitación/economía , Población Urbana
7.
Acad Radiol ; 4(1): 26-34, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9040867

RESUMEN

RATIONALE AND OBJECTIVES: The authors investigated the usefulness of dynamic phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of hepatic function by studying the effect of a fructose load on a rat model of liver cirrhosis. METHODS: In vivo P-31 MR liver spectra of eight rats with bile duct ligature and 10 control rats were obtained every 4.6 minutes before and after intraperitoneal fructose load (10 mmol per kilogram of body weight). RESULTS: In the basal spectra of the experimental group, the phosphomonoester peak was higher than in the control group (P = .026). After the fructose load, the phosphomonoester peak increase and the inorganic phosphate peak decrease were significantly less marked in the experimental group (P = .003). There was a linear correlation between the serum level of bilirubin and the phosphomonoester increase (r = .61, P < .001). CONCLUSION: Dynamic P-31 MR spectroscopy may be useful in the assessment of hepatic function in chronic liver disease.


Asunto(s)
Cirrosis Hepática Experimental/fisiopatología , Hígado/fisiopatología , Espectroscopía de Resonancia Magnética , Análisis de Varianza , Animales , Fructosa , Hígado/metabolismo , Cirrosis Hepática Experimental/metabolismo , Masculino , Fósforo , Ratas , Ratas Wistar
11.
Acta Neurochir (Wien) ; 39(3-4): 233-40, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-304658

RESUMEN

Dorsal column stimulation in two spastic patients with upper motor neurone disease showed the following effects: 1. The subjective feeling of stiffness decreased. During DCS patients were able to walk longer distances without rest. 2. The ability to perform fast alternating or synchronous "pedal-pressing" foot movements improved by 15%. 3. The threshold of H-reflexes was enhanced up to 12%, and outlasted the end of stimulation by two minutes. 4. The H-reflex amplitude was depressed in relation to intensity and duration of DC-stimulation up to 10 minutes after the end of DCS. 5. A late second facilitatory wave at 300 msec in the curve for H-reflexes conditioned by a short tibial stimulus was inhibited during DCS. Although the hyperexcitability of the H-reflex was dampened significantly during DCS the whole motor disturbance improved only slightly.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Neuronas Motoras , Enfermedades Neuromusculares/terapia , Adulto , Amputados , Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Electromiografía , Humanos , Persona de Mediana Edad , Parestesia/etiología , Reflejo , Médula Espinal/fisiología
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