Objective To investigate the effect of ultrasound-and nerve stimulator-guided femoral nerve and lateral femoral cutaneous nerve block versus general anesthesia on knee joint surgery in elderly patients.Methods The 110 elderly patients with spinal anesthetic contraindication and undergoing lower extremity surgery from June 2014 to June 2015 were randomly divided into observation group (n =55) and control group (n =55).The observation group received both ultrasound-and nerve stimulator-guided femoral nerve and lateral femoral cutaneous nerve block,and the control group was given general anesthesia.Anesthesia procedure,sensory block onset time,changes in heart rate and mean artery pressure (MAP) after anesthesia,the total quantity of fluids infusion,dosage of vasopressor and hypotensor,adverse anesthetic reactions,anesthetic fees,anesthetic effect were recorded.Results Anesthetic preparation and practicing time had no difference between the two groups [(8.3 ± 1.7) min vs.(7.7 ± 1.2) min,(t =1.661,P=0.139)].The block onset time was longer in observation group than in control group [(10.3 ± 1.4) min vs.(3.2±0.6) min,t=50.180,P＜0.01].The changes in MAP had significant difference between the two groups [5 min after anesthesia:(89.24 ± 8.30) mmHg and (77.90 ± 8.05) mmHg;after operation:(96.60±8.03) mmHg and (106.22±8.88) mmHg;P＜0.05].There were significant differences in the fluid infusion quantity,dosage of vasopressor and hypotensor,adverse reactions during or after anesthesia,and anesthetic fees between the two groups [(1150.9± 231.6) ml vs.(1400.0±256.5) ml,(3.91±1.21) mg vs.(10.83±2.19)mg,(1.80±0.37) mg vs.(8.27±1.25)mg,3.6％ vs.18.2％,(1239.1±202.9) Yuan vs.(2307.2±205.6) Yuan,all P＜0.05].No significant difference was found in anesthesia effect between the two groups (P =0.198).Conclusions The ultrasound-and nerve stimulator-guided femoral nerve and lateral femoral cutaneous nerve block versus general anesthesia is more simple and safe for the knee joint surgery in elderly patients,with less complications,lower cost and higher satisfaction of patients.

Attributed to the miniaturized body size and active mobility, micro- and nanomotors (MNMs) have demonstrated tremendous potential for medical applications. However, from bench to bedside, massive efforts are needed to address critical issues, such as cost-effective fabrication, on-demand integration of multiple functions, biocompatibility, biodegradability, controlled propulsion and in vivo navigation. Herein, we summarize the advances of biomedical MNMs reported in the past two decades, with particular emphasis on the design, fabrication, propulsion, navigation, and the abilities of biological barriers penetration, biosensing, diagnosis, minimally invasive surgery and targeted cargo delivery. Future perspectives and challenges are discussed as well. This review can lay the foundation for the future direction of medical MNMs, pushing one step forward on the road to achieving practical theranostics using MNMs.

Enzyme-driven micro/nanomotors consuming in situ chemical fuels have attracted lots of attention for biomedical applications. However, motor systems composed by organism-derived organics that maximize the therapeutic efficacy of enzymatic products remain challenging. Herein, swimming proteomotors based on biocompatible urease and human serum albumin are constructed for enhanced antitumor therapy via active motion and ammonia amplification. By decomposing urea into carbon dioxide and ammonia, the designed proteomotors are endowed with self-propulsive capability, which leads to improved internalization and enhanced penetration in vitro. As a glutamine synthetase inhibitor, the loaded l-methionine sulfoximine further prevents the conversion of toxic ammonia into non-toxic glutamine in both tumor and stromal cells, resulting in local ammonia amplification. After intravesical instillation, the proteomotors achieve longer bladder retention and thus significantly inhibit the growth of orthotopic bladder tumor in vivo without adverse effects. We envision that the as-developed swimming proteomotors with amplification of the product toxicity may be a potential platform for active cancer treatment.