Dual-AAV split prime editor corrects the mutation and phenotype in mice with inherited retinal degeneration

The prime editor(PE)can edit genomes with almost any intended changes,including all 12 possible types of base substitutions,small insertions and deletions,and their combinations,without the requirement for double strand breaks or exogenous donor templates.PE demonstrates the possibility of correcting a variety of disease-causing mutations and might expand the therapeutic application of gene editing.In this study,PE was optimized based on a dual-adeno-associated virus(AAV)split-intein system in vitro by screening different split sites and split inteins.We found that splitting PE before amino acid 1105(Ser)of SpCas9 with Rma intein resulted in the highest on-target editing.The orientations of pegRNA and nicking sgRNA in the AAV vector were further optimized.To test the in vivo performance of the optimized dual-AAV split-PE3,it was delivered by subretinal injection in rd12 mice with inherited retinal disease Leber congenital amaurosis.The prime editors corrected the pathogenic mutation with up to 16%efficiency in a precise way,with no detectable off-target edits,restored RPE65 expression,rescued retinal and visual function,and preserved photoceptors.Our findings establish a framework for the preclinical development of PE and motivate further testing of PE for the treatment of inherited retinal diseases caused by various mutations.

Extracorporeal membrane oxygenation in adult patients with sepsis and septic shock: Why, how, when, and for whom

Sepsis and septic shock remain the leading causes of death in intensive care units.Some patients with sepsis fail to respond to routine treatment and rapidly progress to refractory respiratory and circulatory failure,necessitating extracorporeal membrane oxygenation(ECMO).However,the role of ECMO in adult patients with sepsis has not been fully established.According to existing studies,ECMO may be a viable salvage therapy in carefully selected adult patients with sepsis.The choice of venovenous,venoarterial,or hybrid ECMO modes is primarily determined by the patient’s oxygenation and hemodynamics(distributive shock with preserved cardiac output,septic cardiomyopathy(left,right,or biventricular heart failure),or right ventricular failure caused by acute respiratory distress syndrome).Veno-venous ECMO can be used in patients with sepsis and severe acute respiratory distress syndrome when conventional mechanical ventilation fails,and early application of veno-arterial ECMO in patients with sepsis-induced refractory cardiogenic shock may be critical in improving their chances of survival.When ECMO is indicated,the choice of an appropriate mode and determination of the optimal timing of initiation and weaning are critical,particularly in an experienced ECMO center.Furthermore,some special issues,such as ECMO flow,anticoagulation,and antibiotic therapy,should be noted during the management of ECMO support.

Antimicrobial Rubber Nanocapsule-Based Iodophor Promotes Wound Healing

Povidone–iodine has been leading the market of clinical disinfectants worldwide since the last century but has turned a blind eye to its cytotoxic effect on the cells of the human tissue.In this study,a commercial povidone–iodine,though considered an excellent antibacterial agent,was found to have a negative influence on mammal cell growth and wound healing in preclinical trials.At the early stage of wound treatment,it even severely deteriorated the wound and enlarged the wound area.However,our newly formulated iodophors,based on rubber nanoparticles,were able to discriminate between human and bacterial cells by inhibiting the cytotoxicity damage caused by iodine to mammalian tissue and vigorously,killed the bacterial cells,thereby,presenting as superior performers of wound care,compared with povidone–iodine.Wetook advantage of a redox combination of an emulsion complex loaded with iodine to solidify a trans-polyisoprene rubber into nanocapsules.Specifically,our fabricated class of rubber nanocapsules proved to be capable of promoting remarkable cell proliferation and wound recovery,thereby,serving as a promising candidate for biocompatible and healing-favored wound disinfection agents in place of povidone–iodine.

Old inspires new: activation and stabilization of iodine in diene-based rubbers

In 1920,Hermann Staudinger put forward the concept that rubber is composed of isoprene units,which has been considered as the beginning of“macromolecular science”or“polymer science.”The past 100 years’development of polymer science has witnessed the greatness and foresight of this groundbreaking theory.On the occasion of the 100th anniversary of the birth of polymer science,this paper is dedicated to recalling a piece of research history on rubber.

Synthesis of Bio-based Epoxy Containing Phosphine Oxide as a Reactive Additive Toward Highly Toughened and Fire-retarded Epoxy Resins

The integration of high mechanical toughness,impact strength as well as excellent flame-retardant properties toward epoxy resins(EPs)have always been a dilemma.The inadequate overall performance of EPs severely restricts their sustainable utilization in engineering aspects over long-term.Herein,a new bio-based agent(diglycidyl ether of magnolol phosphine oxide,referred as DGEMP)derived from magnolol(classified as lignan),extracted from natural plants Magnolia officinalis,was successfully synthesized and further employed as a flameretardant reactive additive to diglycidyl ether of bisphenol A(DGEBA).As demonstration,the composite resin,DGEBA/15DGEMP(15 wt%DGEMP),achieved an Underwriters Laboratories-94 V-0 rating with a high limiting oxygen index(LOI)value(41.5%).In cone calorimeter tests,it showed that heat release and smoke production were effectively inhibited during combustion,wherein the peak heat release rate(PHRR)value of DGEBA/15DGEMP was reduced by 50%compared to neat DGEBA.Additionally,it exhibited a superior tensile strength(82.8 MPa),toughness(5.11MJ/m^(3))and impact strength(36.5 k J/m^(2)),much higher than that of neat DGEBA(49.7 MPa,2.05 MJ/m^(3)and 20.9 k J/m^(2)).Thus,it is highly anticipated that DGEMP imparts significantly improved mechanical and fire-retarded properties to conventional EPs,which holds a great potential to address the pressing challenges in EP thermosets industry.

少见部位结节性筋膜炎临床病理及分子遗传学特征

目的探讨少见部位结节性筋膜炎(nodular fasciitis, NF)的临床病理、免疫表型及分子遗传学特征。方法收集河南省人民医院病理科2015年1月至2021年1月诊治的50例NF患者的临床及病理资料, 其中少见部位14例, 采用免疫组织化学染色检测相关蛋白的表达情况, 采用荧光原位杂交(FISH)检测USP6基因断裂情况。结果 14例少见部位NF中, 男性、女性各7例, 位于肢端、会阴部、乳腺、腕关节内、腰4/5椎间隙, 其中8例存在少见组织累及(骨骼肌内6例、神经根1例、血管内1例), 肿瘤边界不清, 呈浸润性生长, 梭形肌纤维母细胞束状或杂乱排列, 形态温和, 可见小核仁及多少不等核分裂象, 间质胶原化至黏液样变, 可见红细胞外渗及炎性细胞浸润;免疫组织化学示梭形细胞局灶或部分表达平滑肌肌动蛋白, 弥漫强表达p16。FISH示14例中12例存在USP6基因断裂, 其中2例发生于胸壁骨骼肌内者同时合并USP6基因红色信号扩增。结论少见部位NF具有与经典部位相似的临床病理和遗传学特征, 但肿瘤组织边界多呈浸润性生长, 存在非特异性p16强表达和USP6红色信号扩增现象。少见部位NF的病理诊断需保持高度警惕。

Modulation of Antiviral Immunity and Therapeutic Efficacy by 25-Hydroxycholesterol in Chronically SIV-Infected, ART-Treated Rhesus Macaques

Cholesterol-25-hydroxylase(CH25 H)and its enzymatic product 25-hydroxy cholesterol(25 HC)exert broadly antiviral activity including inhibiting HIV-1 infection.However,their antiviral immunity and therapeutic efficacy in a nonhuman primate model are unknown.Here,we report that the regimen of 25 HC combined with antiretroviral therapy(ART),provides profound immunological modulation towards inhibiting viral replication in chronically SIVmac239-infected rhesus macaques(RMs).Compared to the ART alone,this regimen more effectively controlled SIV replication,enhanced SIVspecific cellular immune responses,restored the ratio of CD4/CD8 cells,reversed the hyperactivation state of CD4^(+)T cells,and inhibited the secretion of proinflammatory cytokines by CD4^(^(+))and CD8^(+)T lymphocytes in chronically SIVinfected RMs.Furthermore,the in vivo safety and the preliminary pharmacokinetics of the 25 HC compound were assessed in this RM model.Taken together,these assessments help explain the profound relationship between cholesterol metabolism,immune modulation,and antiviral activities by 25 HC.These results provide insight for developing novel therapeutic drug candidates against HIV-1 infection and other related diseases.

The Infection and Pathogenicity of SARS-CoV-2 Variant B.1.351 in hACE2 Mice

Dear Editor,Since the outbreak of COVID-19 at the end of 2019,its causative agent SARS-Co V-2 has been spreading around the world for one and half a year.During the long global circulation of SARS-Co V-2,mutations in the viral genome gradually emerged and accumulated。

Dynamic Changes of Antibodies to SARS-CoV-2 in COVID-19 Patients at Early Stage of Outbreak

The coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has spread around the world with high mortality.To diagnose promptly and accurately is the vital step to effectively control its pandemic.Dynamic characteristics of SARSCoV-2-specific antibodies which are important for diagnosis of infection have not been fully demonstrated.In this retrospective,single-center,observational study,we enrolled the initial 131 confirmed cases of COVID-19 at Jin-Yin-Tan Hospital who had at least one-time antibody tested during their hospitalization.The dynamic changes of IgM and IgG antibodies to SARS-CoV-2 nucleocapsid protein in 226 serum samples were detected by ELISA.The sensitivities of IgM and IgG ELISA detection were analyzed.Result showed that the sensitivity of the IgG ELISA detection(92.5%)was significantly higher than that of the IgM(70.8%)(P\0.001).The meantimes of seroconversion for IgM and IgG were6 days and 3 days,respectively.The IgM and IgG antibody levels peaked at around 18 days and 23 days,and then IgM fell to below the baseline level at about day 36,whereas IgG maintained at a relatively high level.In conclusion,antibodies should be detected to aid in diagnosis of COVID-19 infection.IgG could be a sensitive indicator for retrospective diagnosis and contact tracing,while IgM could be an indicator of early infection.

CORRECTION:Correction to: Dynamic Changes of Antibodies to SARS-CoV-2 in COVID-19 Patients at Early Stage of Outbreak

Due to type-setting error,the affiliation of author Huaqing Shu and Shuzhen Wang was mislabeled.The affiliation footnotes in the byline for Huaqing Shu and Shuzhen Wang should read as given above.We apologized for these errors.

Expression pattern and function of SARS-CoV-2 receptor ACE2

Since the outbreak at the end of 2019,SARS-CoV-2 has been spreading around the world for more than one year.Scientists have been intensely conducting research on this newly emerged coronavirus and the disease caused by it.Angiotensin-converting enzyme 2(ACE2),as a receptor mediating the cellular entry of SARSCoV-2,has become a hot spot for researchers.Here,we summarized the recent progresses on the function,expression and distribution characteristics of ACE2 in human body and among populations.We further discussed the interaction mechanism of ACE2 and SARS-CoV-2 S protein,focusing on key residues that effect interaction and binding ability of SARS-CoV-2 variants.This will facilitate researchers to better understand SARS-CoV-2 infection and transmission route,adaptation mechanism,and designing treatment strategies.