Objective To examine the anti-central-fatigue function of maca and its underlying mechanism.Methods Forty Sprague-Dawley rats were divided randomly into a negative control group,model control group,and low-,medium-,and high-dose maca groups(0.6,1.2,and 2.4 g/kg·body weight).Rats in all groups except the negative control group were subjected to multi-factor stimulation,including cold-water swimming,sleep deprivation,restraining,and tail-clamping,to establish central fatigue rat models.Rats in the low-,medium-,and high-dose maca groups received 0.6,1.2,or 2.4 g/kg maca,respectively,by gavage for 35 days.Behavioral testing was carried out using the Morris water-maze,sucrose-preference,and tail-suspension tests.Markers of oxidative stress in the hippocampus,including superoxide dismutase(SOD),malondialdehyde(MDA),and catalase(CAT),were detected using test kits.Proteins connected with the AMP-activated protein kinase(AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)signaling pathway in the hippocampus were detected by Western blot.Results Rats in the low-,medium-,and high-dose maca groups spent significantly more time in the target quadrant compared with the model control group(P＜0.05 or P＜0.01),but there was no significant dose-effect relationship.Rats in the medium-and high-dose maca groups showed decreased escape latency(P＜0.05),increased time crossing the platform location(P＜0.05),increased sucrose preference(P＜0.05),decreased tail suspension time(P＜0.05),increased the activities of CAT(P＜0.01)and SOD(P＜0.05),and decreased MDA content(P＜0.01).Rats in the low-,medium-,and high-dose maca groups also showed significantly increased protein expression levels of AMPK and nuclear respiratory factor 1(P＜0.01 or P＜0.05),but no significant dose-effect relationship was observed.Rats in the medium-and high-dose maca groups showed increased protein expression of PGC-1α(P＜0.05 or P＜0.01),and rats in the high-dose maca group showed increased protein expression of SIRT1 and mitochondrial transcription factor A(P＜0.05 or P＜0.01).Conclusions Maca can improve the indicators of central fatigue in rats,determined by behavioral testing and oxidative stress-related factors.The underlying mechanism may be related to its regulatory effects on the AMPK/SIRT1/PGC-1α signaling pathway.

Objective To examine the anti-central-fatigue function of maca and its underlying mechanism.Methods Forty Sprague-Dawley rats were divided randomly into a negative control group,model control group,and low-,medium-,and high-dose maca groups(0.6,1.2,and 2.4 g/kg·body weight).Rats in all groups except the negative control group were subjected to multi-factor stimulation,including cold-water swimming,sleep deprivation,restraining,and tail-clamping,to establish central fatigue rat models.Rats in the low-,medium-,and high-dose maca groups received 0.6,1.2,or 2.4 g/kg maca,respectively,by gavage for 35 days.Behavioral testing was carried out using the Morris water-maze,sucrose-preference,and tail-suspension tests.Markers of oxidative stress in the hippocampus,including superoxide dismutase(SOD),malondialdehyde(MDA),and catalase(CAT),were detected using test kits.Proteins connected with the AMP-activated protein kinase(AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator-activated receptor γ coactivator 1-α(PGC-1α)signaling pathway in the hippocampus were detected by Western blot.Results Rats in the low-,medium-,and high-dose maca groups spent significantly more time in the target quadrant compared with the model control group(P＜0.05 or P＜0.01),but there was no significant dose-effect relationship.Rats in the medium-and high-dose maca groups showed decreased escape latency(P＜0.05),increased time crossing the platform location(P＜0.05),increased sucrose preference(P＜0.05),decreased tail suspension time(P＜0.05),increased the activities of CAT(P＜0.01)and SOD(P＜0.05),and decreased MDA content(P＜0.01).Rats in the low-,medium-,and high-dose maca groups also showed significantly increased protein expression levels of AMPK and nuclear respiratory factor 1(P＜0.01 or P＜0.05),but no significant dose-effect relationship was observed.Rats in the medium-and high-dose maca groups showed increased protein expression of PGC-1α(P＜0.05 or P＜0.01),and rats in the high-dose maca group showed increased protein expression of SIRT1 and mitochondrial transcription factor A(P＜0.05 or P＜0.01).Conclusions Maca can improve the indicators of central fatigue in rats,determined by behavioral testing and oxidative stress-related factors.The underlying mechanism may be related to its regulatory effects on the AMPK/SIRT1/PGC-1α signaling pathway.

Objective To assess the clinic value of transthoracic echocardiography in diagnosis of infective endocarditis.Methods Transthoracic echocardiography features and clinic data of 114 patients with infective endocarditis were analyzed retrospectively.The form,activity and coaptation of cardiac valve were observed.The vegetation was found,and the surrounding structure of valve and fundamental heart disease were studied.Results Among 114 patients,the primary symptom presented as fever in 104 patiens.Fundamental heart disease was found in 69 patients;and systemic disease was found in 5 patients.Blood culture was positive in 35 patients.Mitral valve was involved in 46 patients.Aortic valve was involved in 48 patients.Tricuspid valve was involved in 17 patients.Pulmonary valve was involved in 1 patient.Prosthetic valve was infected in 9 patients.Multi-valves were infected in 7 patients.There were serious complications in 19 patients.Ultrasound showed vegetation in 56 of 59 patients underwent surgery.And the diagnostic accuracy rate was 94.92％ (56/59).Conclusion Transthoracic echocardiography can be used to accurately diagnose infective endocarditis.