RESUMEN
AIM: Evaluation of the capability of Burkholderia sacchari to incorporate different monomers into polyhydroxyalkanoates (PHA). METHODS AND RESULTS: Thirty different carbon sources were evaluated as cosubstrates for B. sacchari growing on glucose with the intention to promote the incorporation of different monomers into the PHA produced by this species. With odd-numbered fatty acids, incorporation of the 3HV monomer was achieved, up to 65 mol% in the case of valerate. With 4-hydroxybutyrate, incorporation of 4HB was obtained, representing 9·1 mol%. With hexanoic acid, the production of P3HB-co-3HHx was achieved, containing up to 1·6 mol% of 3HHx. The molar fraction of 3HHx was found to be dependent on the ratio of glucose to hexanoic acid supplied. Metabolic flux analysis revealed a high efficiency of B. sacchari in converting carbon sources into P3HB-co-3HHx. Nevertheless, hexanoic acid was only poorly converted to 3HHx. CONCLUSIONS: Burkholderia sacchari is able to incorporate 3HV, 4HB and 3HHx in PHA containing mainly 3HB. The 3HHx content of P3HB-co-3HHx can be controlled by varying the glucose to hexanoic acid ratio. Burkholderia sacchari is highly efficient in converting carbon sources into PHA; however, only 2% of the hexanoic acid supplied could be converted to 3HHx. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report describing an approach to modulate the composition of P3HB-co-3HHx produced by bacteria using mixtures of carbohydrate and hexanoic acid as carbon source.
Asunto(s)
Burkholderia/metabolismo , Polihidroxialcanoatos/biosíntesis , Caproatos/metabolismo , Carbono/metabolismo , Glucosa/metabolismo , Hidroxibutiratos/metabolismoRESUMEN
Las prótesis totales de rodilla constituyen uno de los implantesmás colocados en el ámbito de la ortopedia. El númerode modelos existentes en el mercado es muy elevadoy todos tienen sus características. A pesar de ello podemosagrupar las artroplastias de rodilla por estas caracterísricas,siendo las prótesis de platillo móvil el grupo más novedoso.Revisamos la bibliogrfía más reciente sobre la biomecánicade las prótesis totales de rodilla, englobando aspectos comolos materiales, el polietileno, la fijación, la geometría ola presencia del ligamento cruzado posterior para entenderen profundidad el funcionemiento de una PTR
Total knee prostheses (TKAs) are one of the most frequentimplants we use like orthpaedists. There are a largenumber of models and all of them have their characteristics.Despite of it we can group TKAs in avery few ones inwhich mobile-bearing arthroplasty in the newness. We reviewthe literature about biomechanics of TKAs includingmaterials, UHMWPE, fixation of the prostheses, geometryor presence of the cruciate posterior ligament to really understandarthroplasty working
Asunto(s)
Humanos , Fenómenos Biomecánicos/métodos , Prótesis de la Rodilla/clasificación , Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla/cirugíaRESUMEN
La biomecánica de la rodilla todavía no se conoce exactamente.Diversos patrones se han establecido, pero ningunoha alcanzado el funcionamiento real de la articulación.Revisamos la bibliografía y presentamos la evolucióndel entendimiento del movimiento de la rodilla hasta llegaral modelo de seis grados de libertad en la zona patelofemoraly en la tibiofemoral. Este modelo parece ser el másaproximado a la realidad en cuanto a la cinemática de larodilla
Knee´s biomechanics is not well known yet. A largenumber of patterns has been stablished, but neither ofthem has reached the right articular movement. We reviewthe literature and present the understanding about kneemovement until six grades of freedom model in patello-femoraland tibio-femoral zones. This model seems to be themost approximate to reality in knee kinematics
