RESUMEN
While dehydrogenases play crucial roles in tricarboxylic acid (TCA) cycle of cell metabolism, which are extensively explored for biomedical and chemical engineering uses, it is a big challenge to overcome the shortcomings (low stability and high costs) of recombinant dehydrogenases. Herein, it is shown that two-dimensional (2D) SnSe is capable of mimicking native dehydrogenases to efficiently catalyze hydrogen transfer from 1-(R)-2-(R')-ethanol groups. In contrary to susceptible native dehydrogenases, lactic dehydrogenase (LDH) for instance, SnSe is extremely tolerant to reaction condition changes (pH, temperature, and organic solvents) and displays extraordinary reusable capability. Structure-activity analysis indicates that the single-atom structure, Sn vacancy, and hydrogen binding affinity of SnSe may be responsible for their catalytic activity. Overall, this is the first report of a 2D SnSe nanozyme to mimic key dehydrogenases in cell metabolism.
Asunto(s)
Materiales Biomiméticos/química , Nanoestructuras/química , Selenio/química , Estaño/química , Materiales Biomiméticos/metabolismo , Catálisis , Concentración de Iones de Hidrógeno , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Temperatura , TermodinámicaRESUMEN
OBJECTIVE: To report the therapeutic effectiveness and feasibility of electroacupuncture (EA) treatment in patients with urinary retention which is caused by cauda equina injury and refractory to conventional conservative treatments. METHODS: From 9 August 2007 to 10 May 2010 prospective evaluation was carried out in 15 patients with neurogenic urinary retention secondary to cauda equina injury who underwent EA treatment at bilateral points BL32, BL33 and BL35. All patients received five sessions of EA treatment each week for the first 4 weeks, three sessions a week for the following 2 weeks, and then were followed up for 6 months. Voiding abilities, postvoiding residual urine volume (RUV) and maximum urinary flow rate (Qmax) were documented as outcome measures. RESULTS: After 6 weeks' EA treatment, 10/15 enrolled patients regained their self-voiding ability, and the mean postvoiding RUV for all patients decreased by 303.6±148.8 ml. In nine patients with documented data, Qmax increased by 11.0±6.3 ml/s. In nine patients, voiding difficulties changed from severe to mild. At the end of 6 months' follow-up, 8/10 patients retained their regained self-voiding ability, whereas two patients had lost their voiding ability again. CONCLUSION: The results indicate that the EA treatment may have longlasting therapeutic effectiveness in the management of neurogenic urinary retention secondary to cauda equina injury.