Central swallowing in normal adults using functional magnetic resonance imaging

BACKGROUND： While brain-imaging studies in healthy adults have indicated that multiple cortical regions are involved in swallowing, these functional imaging techniques have not been extensively applied to the complete understand neurophysiology of swallowing in China. A full understanding of normal swallowing neurophysiology is important for improving functional outcomes for dysphagia due to neurologic disorders or damage with increasing age. Thus the interpretations of the functional contributions of various brain areas in swallowing should be scientifically researched. OBJECTIVE： To identify the activation and characteristic of swallowing center in healthy adults using functional magnetic resonance imaging. DESIGN, TIME AND SETTING： An uncontrolled neuroimaging study was performed at the Outpatient Clinic, Department of Radiology, West China Hospital of Sichuan University between March and November 2008. PARTICIPANTS： Ten healthy right-handed volunteers, aged over 20 years with a mean age of （34.2 ＋ 8.1） years, a range of 25-45 years and including five males and five females participated. A medical history was obtained from all potential subjects and all subjects were free of systemic diseases and neurological disorders. METHODS： The healthy volunteers were examined with event-related functional magnetic resonance imaging of blood oxygenation level-dependent while laryngeal swallow-related movements were recorded. Subjects were scanned during voluntary saliva swallowing and water bolus swallowing activation tasks. Data was processed using the General Linear Model. A voxel by voxel group comparison was performed using random effect analysis. Any cluster with a corrected P 〈 0.05 for spatial extent was considered significant. MAIN OUTCOME MEASURES： The cerebral cortical activation maps of voluntary swallowing of saliva and swallowing of water bolus in healthy adults were observed. RESULTS： A multifocal cortical representation of swallowing was in the precentral gyrus, postcentral gyrus, insula, anterior cingulate gyrus, thalamus, basal ganglia and cerebellum, in a bilateral and asymmetrical manner, predominantly on the left hemisphere in the volunteers （P 〈 0.05）. CONCLUSION： Activation of the cortex during normal swallowing tasks may be functionally linked to basal nuclei, thalamus, and cerebellum, greatly appearing in the left hemisphere.

Signaling pathways and targeted therapy for myocardial infarction

Although the treatment of myocardial infarction(MI)has improved considerably,it is still a worldwide disease with high morbidity and high mortality.Whilst there is still a long way to go for discovering ideal treatments,therapeutic strategies committed to cardioprotection and cardiac repair following cardiac ischemia are emerging.Evidence of pathological characteristics in MI illustrates cell signaling pathways that participate in the survival,proliferation,apoptosis,autophagy of cardiomyocytes,endothelial cells,fibroblasts,monocytes,and stem cells.These signaling pathways include the key players in inflammation response,e.g.,NLRP3/caspase-1 and TLR4/MyD88/NF-κB;the crucial mediators in oxidative stress and apoptosis,for instance,Notch,Hippo/YAP,RhoA/ROCK,Nrf2/HO-1,and Sonic hedgehog;the controller of myocardial fibrosis such as TGF-β/SMADs and Wnt/β-catenin;and the main regulator of angiogenesis,PI3K/Akt,MAPK,JAK/STAT,Sonic hedgehog,etc.Since signaling pathways play an important role in administering the process of MI,aiming at targeting these aberrant signaling pathways and improving the pathological manifestations in MI is indispensable and promising.Hence,drug therapy,gene therapy,protein therapy,cell therapy,and exosome therapy have been emerging and are known as novel therapies.In this review,we summarize the therapeutic strategies for MI by regulating these associated pathways,which contribute to inhibiting cardiomyocytes death,attenuating inflammation,enhancing angiogenesis,etc.so as to repair and re-functionalize damaged hearts.

Targeting cellular senescence prevents glucocorticoid-induced bone loss through modulation of the DPP4-GLP-1 axis

Dear Editor,Glucocorticoids(GCs)often cause detrimental side effects,including osteoporosis and osteonecrosis,with no specific drugs available to circumvent these problems.1 Cellular senescence plays an essential role in bone loss,2,3 where senescent cells release various factors,termed senescence-associated secretory phenotype(SASP),which influences neighboring cells and disrupts normal tissues.2 Glucocorticoids can induce senescence in bone cells in young mice;2 however,the effects of GCs on senescence and SASP during bone metabolism in adult mice are unclear.