Identifying biomarkers predicting clinical response to treatment of PD-1/PD-L1 pathway blockade can guide patient selection and therapeutic individualization.Some researches have shown that patients with cancer will acquire better clinical effects by blocking PD-1/PD-L1 pathway whose characteristics include higher pretreatment expression of PD-L1 by tumor cells or tumor infiltrating immune cells,the massive infiltration of intratumoral CD8 + T cells,the high mutation frequency of tumor cell gene.These biomarkers are expected to become indicators which can select patients.

Objective　To evaluate the diagnostic value of superb microvascular imaging(SMI) in cervical artery dissection.Methods　A total of 42 patients with cervical artery dissection diagnosed by the Department of Neurology of our hospital from June 2017 to June 2021 were collected to evaluate the consistency of SMI and CTA/MRA+DSA in the diagnosis of cervical artery dissection,and to compare the accuracy and sensitivity of SMI.Results　Among 42 patients,the positive rate of cervical artery dissection with ultrasonography,SMI,CTA or MRA and DSA were 42.8 %（18/42）,90.4% （38/42） and 92.6%（39/42） respectively.The DSA mostly showed the line-like sign(n=19,48.7%); Ultrasonography and SMI mostly showed the intramural hematoma.SMI and CTA/MRA+DSA showed the good consistency in the diagnosis of cervical artery dissection（Kappa=0.340，P=0.056).Superb microvascular imaging was superior to ultrasonography in the detection of cervical artery dissection（Kappa=5.895，P=0.015）.The area under the ROC superb microvascular imaging diagnosis of cervical artery dissection was 0.966.It is suggested that superb microvascular imaging has high accuracy in diagnose cervical artery dissection.Conclusion　Superb microvascular imaging has high clinical value in the diagnosis of various types of cervical artery dissection.

Biodegradable polyamines have long been studied as potential recombinant viral gene vectors. Spermine (SPE) is an endogenous tetra-amine with excellent biocompatibility yet poor gene condensation capacity. We have previously synthesized a polyspermine based on SPE and poly(ethylene glycol) (PEG) diacrylate (SPE-alt-PEG) for enhanced transfection performance, but the synthesized SPE-alt-PEG still lacked specificity towards cancer cells. In this study, folic acid (FA) was incorporated into SPE-alt-PEG to fabricate a targeted gene delivery vector (FA-SPE-PEG) via an acylation reaction. FA-SPE-PEG exhibited mild cytotoxicity in both cancer cells and normal cells. FA-SPE-PEG possessed higher transfection efficiency than PEI 25 K and Lipofectamine(®) 2000 in two tested cancer cell lines at functional weight ratios, and its superiority over untargeted SPE-alt-PEG was prominent in cells with overexpressed folate receptors (FRs). Moreover, in vivo delivery of green fluorescent protein (GFP) with FA-SPE-PEG resulted in highest fluorescent signal intensity of all investigated groups. FA-SPE-PEG showed remarkably enhanced specificity towards cancer cells both in vivo and in vitro due to the interaction between FA and FRs. Taken together, FA-SPE-PEG was demonstrated to be a prospective targeted gene delivery vector with high transfection capacity and excellent biocompatibility.