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1.
J Hum Nutr Diet ; 33(4): 574-583, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31989752

RESUMEN

BACKGROUND: Change promotes quality in healthcare, yet adopting change can be challenging. Understanding how change in nutrition care is adopted may support better design and implementation of interventions that aim to address inadequate food intake in hospital. The present study followed the process of change in a healthcare organisation, exploring staff attitudes, beliefs and experiences of the implementation of a mealtime intervention. METHODS: In total, 103 h of fieldwork were conducted in this longitudinal ethnographic study over a 4-month period. Over 170 staff participated, with data captured using observation, interviews and focus groups. Data were analysed using an inductive, thematic approach, informed by implementation theory. RESULTS: Attitudes and experiences of change in nutrition care are described by three themes: (i) staff recognised the inevitability of change; (ii) staff cooperated with the intervention, recognising potential value in the intervention to support patient care, where increased awareness of their mealtime behaviours supported adopting practice changes; and (iii) some staff were able to reflect on their practice after implementing the intervention, whereas others could not. A model illustrating the interconnectedness of factors influencing implementation emerged from the research, guiding future nutrition care intervention design and supporting change. CONCLUSIONS: The requirement to address the underlying perceptions of staff about the need to change should not be underestimated. Increased efforts to market the change message to specific staff groups and physical behavioural reinforcement strategies are needed. Nutrition care in the future should focus on helping staff feel positive about making practice changes.


Asunto(s)
Actitud del Personal de Salud , Terapia Nutricional/psicología , Innovación Organizacional , Personal de Hospital/psicología , Lugar de Trabajo/psicología , Adulto , Antropología Cultural , Australia , Femenino , Grupos Focales , Humanos , Estudios Longitudinales , Masculino , Comidas , Persona de Mediana Edad , Investigación Cualitativa , Lugar de Trabajo/organización & administración
2.
Cell Biol Int ; 29(8): 629-37, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16024262

RESUMEN

The homeopathic compound of resonance FMS*Calciumfluor (FMS*) reportedly promotes osteogenic differentiation of rat pre-osteoblasts in vitro. Here, we show that the continuous exposure of differentiating rat osteogenic cells (ROB) to FMS* modulates the level of expression of mRNAs for 7 of the 8 osteogenic markers tested. Alkaline phosphatase (AP), osteocalcin (OC), metalloproteinases (MMP-2 and -14), procollagenase C (BMP-1), biglycan (BG) and integrin 1 are expressed at higher levels in FMS*-treated osteoblasts than in control cultures. MMP-2 and -14 mRNA are not down-modulated at mineralization. Also, the pattern of expression induced by FMS* for some of these genes (BMP-1, BG and integrin 1) is changed, but collagen type I (Coll I) mRNA levels are not affected by treatment with FMS*. This suggests that FMS* modulates mRNA levels and that this is not generalized, but gene(s) specific. We also report that exposure to FMS* rapidly and transiently induces activation of mitogen-activated protein kinases (MAPKs) 42,44 in populations of early osteoblasts, but not in pre-osteoblasts, with a cell differentiation stage-dependent and pertussis toxin (PTX)-sensitive response. Subsequent to FMS* MAPK signaling activation, an increase in AP and MMP-14 mRNA is detected, which is also inhibited by PTX, suggesting that FMS* activation of MAPK signaling could be an early event required for the induction of these genes. Exposure to FMS* does not cause changes in the activity of p125 (FAK)-mediated signaling.


Asunto(s)
Fluoruros/farmacología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Osteoblastos/citología , Osteogénesis/efectos de los fármacos , Proteínas Tirosina Quinasas/metabolismo , ARN Mensajero/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Biomarcadores/metabolismo , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Adhesiones Focales , Homeopatía , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Toxina del Pertussis/farmacología , ARN Mensajero/genética , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Tibia
3.
Chem Res Toxicol ; 16(7): 865-72, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12870889

RESUMEN

Previous investigations have implicated green tea to exert chemopreventive effects in animal models of chemical carcinogenesis, including polycyclic aryl hydrocarbon-induced cancers. In an effort to understand the compound(s) responsible for this protection, the effects of green tea extracts (GTE) and individual green tea catechins on aryl hydrocarbon receptor (AhR) gene induction were determined. Green tea (GT) was organically extracted and subsequently fractionated by column chromatography. The chemical composition of each fraction was determined by NMR. Several fractions inhibited tetrachlorodibenzo-p-dioxin-induced transcription of a dioxin responsive element-dependent luciferase reporter in stably transfected mouse hepatoma cells in a concentration-dependent manner. To determine the GT component(s) responsible for the observed effects, individual catechins were tested in the luciferase reporter system at concentrations found within the active fractions. Of the catechins tested, epigallocatechingallate (EGCG) and epigallocatechin (EGC) were the most potent antagonists, with IC(50) values of 60 and 100 microM, respectively. Re-creation of the active fractions using commercially available catechins further confirmed the identification of EGCG and EGC as the active AhR antagonists in green tea. These data suggest that EGCG and EGC are capable of altering AhR transcription and are responsible for most, if not all, of the AhR antagonist activity of GTE.


Asunto(s)
Catequina/análogos & derivados , Catequina/antagonistas & inhibidores , Catequina/análisis , Extractos Vegetales/química , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Té/química , Animales , Catequina/farmacología , Relación Dosis-Respuesta a Droga , Genes Reporteros/efectos de los fármacos , Luciferasas/genética , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Extractos Vegetales/farmacología , Dibenzodioxinas Policloradas/metabolismo , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Transcripción Genética/efectos de los fármacos , Células Tumorales Cultivadas
4.
Rev. esp. nutr. comunitaria ; 7(3/4): 61-68, jul. 2001. tab
Artículo en Es | IBECS | ID: ibc-26969

RESUMEN

Habiendo analizado en estudiantes de nutrición (1998) el consumo de edulcorantes no nutritivos (ENN), productos que lo contengan y el uso de los mismos por la Industria, se continúa con la línea de investigación, analizando otras "poblaciones riesgo" (PR).Objetivos: Determinar en el término de un año (98/99) la variación en la Industria de productos dietéticos (PD) con ENN. Establecer su manejo y prevalencia de consumo en PR y porcentaje de adecuación en relación a la ingesta diaria admisible (IDA) para cada uno. Metodología: Se estudió como ENN la Sacarina (S), Ciclamato©, Acesulfame K (Ac), Aspartamo (A) y Sucralosa (Su). Población n=290 sexo femenino. Se consideró PR a la expuesta al mayor consumo de PD y ENN, ya sea por situación fisiopatológica presente, período biológico o influencias de medios de comunicación. Se establecieron 3 grupos: adolescentes n=80; adultas en edad fértil n=120 y perimenopáusicas n=90.Resultados: El uso por la Industria de PD y ENN aumentó en un año un 49,1 por ciento incorporándose la Su y aumentando la utilización de Ac:100,0 por ciento, A:28,6 por ciento, C: 25,7 por ciento y S:12,5 por ciento. El rubro de PD que más creció fue el de yogures (157,1 por ciento).Con respecto al manejo de PD y ENN, en las 3 poblaciones estudiadas, la mayoría "se cuida" o no realiza ninguna alimentación especial; utilizan como criterio para seleccionar a los PD el sabor de los mismos; leen el rotulado nutricional, principalmente el aporte calórico y los ENN son seleccionados también por el sabor. Los PD más consumidos son chicles, mermeladas, jugos, gelatinas, gaseosas, yogures, edulcorantes, frutas enlatadas, flanes y postres de leche y alfajores. No hubo variaciones en las marcas consumidas con el estudio anterior. Con respecto al porcentaje de adecuación para la IDA, la mayoría (90 por ciento) se encuentra por debajo del 25 por ciento de adecuación para S, C, A y Ac. Ninguno supera el 100 por ciento de adecuación. No se pudo determinar la adecuación para la Su, por no declarar el rotulado la cantidad contenida en los productos. Conclusiones: Pese a la mayor disponibilidad y aumento del uso por la industria de PD con ENN, se observa en el consumo que el porcentaje de adecuación para la IDA de cada uno de ellos, es menor al 25 por ciento (AU)


Asunto(s)
Adolescente , Adulto , Persona de Mediana Edad , Humanos , Suplementos Dietéticos , 24457 , Edulcorantes , Prevalencia , Grupos de Riesgo , Reproducibilidad de los Resultados , Edulcorantes/clasificación
5.
Boll Soc Ital Biol Sper ; 76(5-6): 29-36, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11449818

RESUMEN

We studied the involvement of G-proteins in transducing the inductive signal generated by treatment of tibial-derived neonatal rat osteoblasts (ROB) cultured in vitro with FMS*Calciumfluor, a homeopathic preparation utilized in the therapy of osteoporosis. We previously reported that FMS*Calciumfluor acts as inducer and potentiator of osteogenic differentiation in vitro, among other effects, by increasing the expression of Alkaline phosphatase (AP). We utilized Pertussis Toxin (PTX), an inhibitor of G alpha 0/G alpha i proteins, Mastoparan 7, an activator of G alpha 0/G alpha i proteins and Cholera Toxin (CTX), a stimulator of G alpha s protein to show involvement of specific G proteins in the inductive effect on AP of FMS*Calciumfluor. We here show that the increase in AP expression induced by FMS*Calciumfluor is dependent on the activation of G alpha 0/G alpha i proteins, while it is unaffected by the activation stage of the G alpha s protein. Moreover, we show that the expression of endogenous AP during osteogenesis in vitro is regulated independently from G proteins, and unaffected by their activation stage and therefore that treatment with FMS*Calciumfluor activates a new pathway of cellular response.


Asunto(s)
Fosfatasa Alcalina/biosíntesis , Calcio/fisiología , Proteínas de Unión al GTP Heterotriméricas/fisiología , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Animales , Células Cultivadas , Toxina del Pertussis , Ratas , Tibia/fisiología , Factores de Virulencia de Bordetella/farmacología
6.
Cell Biol Int ; 23(1): 31-40, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10527546

RESUMEN

We studied the effects of in vitro treatment of differentiating osteogenic cells with FMS*Calciumfluor, to determine whether it caused changes in proliferative or differentiation potential of osteoblasts. FMS*Calciumfluor was developed for the therapy of post-menopausal and age-related osteoporosis on the basis of the principles of resonance homeopathy and VTR Vega test. Its daily prescribed therapeutical usage is about 30,000-fold less in fluoride concentration than that recommended for NaF associated with calcium monophosphate. Rat tibial osteoblast (ROB) primary cultures represent populations of early osteoblasts and their derivative cultures of more than 60 cumulative population doubling (CPD) represent more mature osteogenic cells. Both these populations were shown to undergo in vitro differentiation, as monitored by the sequential expression of markers that define the stages of the osteogenic progression. Here we report that continual treatment of ROB during osteogenesis with FMS*Calciumfluor modulated the expression of critical osteogenic markers: alkaline phosphatase (AP), an indicator of osteoblast maturation, and(45)Ca incorporation into the matrix and nodule formation, events of the last phase of osteogenesis and a measure of osteoid mineralization. Treatment did not affect proliferation, or expression and activation of metalloproteinases (MMP). AP activity and levels of AP mRNA were increased by treatment with FMS*Calciumfluor; the incorporation of radiolabelled Ca into the matrix was also increased and the formation of nodules occurred in a shorter time and with higher frequency than in untreated control cultures. The effects of FMS*Calciumfluor were concentration dependent and specific for its modalities of preparation, and were observed at a concentration about three orders of magnitude lower than similar effects reported in the literature by treatment of osteoblast cultures in vitro with NaF.


Asunto(s)
Fluoruros/farmacología , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Tibia , Animales , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Homeopatía , Osteoblastos/citología , Ratas
7.
Bone ; 21(1): 31-9, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9213005

RESUMEN

Postproliferative confluent cultures of primary rat tibial osteoblasts (ROB), cultured in medium supplemented with ascorbic acid and beta-glycerophosphate (AS-bGP, differentiation medium) express, in sequence, specific bone markers which identify a succession of maturation stages, and eventually form mineralized noduli. We report an investigation on the effect of extensive proliferation in vitro in unsupplemented medium on the osteogenic potential of mass cultures of ROB. The growth rates of the populations, derived from two independent primary cultures, was constant throughout 110 cumulative population doublings (CPD) in culture. Propagated cells maintained features similar to osteoblasts in primary cultures with respect to serum and anchorage dependence for growth and to the chemokinetic effect on endothelial cells exerted by their conditioned media (CM). Propagated populations, set at confluence in differentiation medium, were tested for the expression of early [alkaline phosphatase (AP)] and late [osteocalcin (OC); bone sialoprotein (BSP); 45Ca incorporation and mineralization] osteogenic markers. We observed an increase, parallel to the increase in CPD, in both the level of maximal expression of AP (enzyme/microgram cellular DNA) and in the frequency of nodules, reaching five- to sixfold (at 78 CPD) and eightfold (at 60 CPD), respectively, the levels of primary cultures. AP expression (enzyme and mRNA) persisted during mineralization and 45Ca incorporation. The time required by propagated cultures for the formation of nodules decreased with increase of CPD, and was reduced to less than one third at 87 CDP. Nodules became mineralized over a similar lapse of time as in primary cultures and were positive by histochemistry for BSP and OC. We also obtained osteogenic clones from two independent cultures after 72 CPD. 90% of these showed an osteoblast phenotype, expressing AP and forming nodules positive for OC and BSP, which mineralized. Timing of formation and frequency of nodules/plated cells in clones was similar to that found in propagated cultures of equivalent CPD. In summary, propagated ROB populations and derived clones showed enhanced osteoblast phenotype, possibly due to an increase in osteogenic cells and enrichment of proliferating mature osteoblasts, consequent to extended propagation in culture.


Asunto(s)
Osteoblastos/citología , Osteogénesis/fisiología , Fosfatasa Alcalina/biosíntesis , Animales , Ácido Ascórbico/farmacología , Northern Blotting , Calcificación Fisiológica/efectos de los fármacos , Calcificación Fisiológica/fisiología , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Diferenciación Celular/fisiología , División Celular/efectos de los fármacos , División Celular/fisiología , Células Cultivadas , Quimiotaxis , Clonación Molecular , Medios de Cultivo Condicionados , ADN/análisis , Fluorometría , Glicerofosfatos/farmacología , Inmunohistoquímica , Sialoproteína de Unión a Integrina , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Osteocalcina/biosíntesis , Osteogénesis/efectos de los fármacos , Fenotipo , ARN Mensajero/análisis , Ratas , Ratas Wistar , Sialoglicoproteínas/biosíntesis , Tibia/citología
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