Dissolvable microneedle-based wound dressing transdermally and continuously delivers anti-inflammatory and pro-angiogenic exosomes for diabetic wound treatment

Due to overactive inflammation and hindered angiogenesis,self-healing of diabetic wounds(DW)remains challenging in the clinic.Platelet-derived exosomes(PLT-Exos),a novel exosome capable of anti-inflammation and pro-angiogenesis,show great potential in DW treatment.However,previous administration of exosomes into skin wounds is topical daub or intradermal injection,which cannot intradermally deliver PLT-Exos into the dermis layer,thus impeding its long-term efficacy in anti-inflammation and pro-angiogenesis.Herein,a dissolvable microneedle-based wound dressing(PLT-Exos@ADMMA-MN)was developed for transdermal and long-term delivery of PLT-Exos.Firstly,a photo-crosslinking methacrylated acellular dermal matrix-based hydrogel(ADMMA-GEL),showing physiochemical tailorability,fast-gelling performance,excellent biocompatibility,and pro-angiogenic capacities,was synthesized as a base material of our dressing.For endowing the dressing with anti-inflammation and pro-angiogenesis,PLT-Exos were encapsulated into ADMMA-GEL with a minimum effective concentration determined by our in-vitro experiments.Then,in-vitro results show that this dressing exhibits excellent properties in anti-inflammation and pro-angiogenesis.Lastly,in-vivo experiments showed that this dressing could continuously and transdermally deliver PLT-Exos into skin wounds to switch local macrophage into M2 phenotype while stimulating neovascularization,thus proving a low-inflammatory and pro-angiogenic microenvironment for DW healing.Collectively,this study provides a novel wound dressing capable of suppressing inflammation and stimulating vascularization for DW treatment.

A preliminary study of early agriculture practices at the Haojiatai site in Luohe city,Henan Province

As the most fundamental economic sector of human societies,farming has played a significant role in interactions between humans and the environment.The study of crop patterns in various regions could not only clarify the economic foundations of early societies,but also greatly improve our understanding of interactions among human beings,the environment,and other creatures.In this regard,this study focuses on early agriculture practices at the Haojiatai site,situated in the cultural and natural transitional region between North and South China.Macro plant remains from this site reveal that foxtail millet was the most important staple crop here during the Longshan and Xinzhai periods(4300–3800 cal.yr BP),along with common millet and a small amount of rice and soybean.This crop pattern is in contrast to the ancient environmental conditions of this region,and cultural factors such as agriculture traditions and food preferences may have been more important in the formation process of this crop pattern.

Water Net: An adaptive matching pipeline for segmenting water with volatile appearance

We develop a novel network to segment water with significant appearance variation in videos.Unlike existing state-of-the-art video segmentation approaches that use a pre-trained feature recognition network and several previous frames to guide segmentation,we accommodate the object’s appearance variation by considering features observed from the current frame.When dealing with segmentation of objects such as water,whose appearance is non-uniform and changing dynamically,our pipeline can produce more reliable and accurate segmentation results than existing algorithms.