Exosomes are cell-derived nanovesicles that are involved in the intercellular transportation of materials. Therapeutics, such as small molecules or nucleic acid drugs, can be incorporated into ...exosomes and then delivered to specific types of cells or tissues to realize targeted drug delivery. Targeted delivery increases the local concentration of therapeutics and minimizes side effects. Here, we present a detailed review of exosomes engineering through genetic and chemical methods for targeted drug delivery. Although still in its infancy, exosome-mediated drug delivery boasts low toxicity, low immunogenicity, and high engineerability, and holds promise for cell-free therapies for a wide range of diseases.
As one of the common languages in the world, English is playing a more and more important role in trade exchanges, cultural exchanges, and other transnational cooperation. In order to better ...integrate into the world and communicate with the world, China began to vigorously expand English learning as early as the late 1980s. However, with the development trend of economic globalization and cultural diversity, the traditional English ability evaluation methods are not enough to comprehensively measure individual English ability. Therefore, based on this background, this paper introduces the clustering algorithm into English ability evaluation, improves the traditional clustering algorithm represented by K-means on the basis of predecessors, and captures the evaluation data through neural network algorithm combined with the background of modern big data framework. The results show that the fuzzy logic feature mapping clustering algorithm (FLFM) proposed in this paper performs better than the traditional evaluation algorithm, and the evaluation effectiveness and comprehensiveness are improved by about 10 pt.
•Children and adolescents who are often neglected in the wake of the outbreak were taken as subjects to investigate their mental health status and analyze the related influencing factors during the ...global pandemic of COVID-19.•The presence of clinical depressive symptoms, resident in urban regions, implementation of the precaution and control measures, being female, having a family member or friend infected with coronavirus were associated with increased levels of anxiety.•Smartphone addiction, Internet addiction, resident in Hubei province and urban areas, family members or friends infected with coronavirus, graduation affected by the epidemic, levels of separation anxiety, physical injury fear, and tendency to adopt an emotion-focused coping style were associated with increased levels of respondents’ depressive symptoms.•It's urgent to concern and address emotional distress for children and adolescents during the epidemic. Targeted intervention measures could be formulated based on the significant influencing factors on anxiety and clinical depressive symptoms.
: The sudden outbreak of Coronavirus Disease 2019 (COVID-19) has had a dramatic effect on the mental health of the public. In the present study, we demonstrated the psychological effects on children and adolescents associated with the epidemic .
: By using convenience sampling method, questionnaires, such as Spence Child Anxiety Scale, Child Depression Inventory and Coping style Scale, were distributed to participating 359 children and 3254 adolescents online.
: The anxiety levels of children and adolescents were (23.87 ± 15.79) and (29.27 ± 19.79), respectively. 22.28% respondents were suffering from depressive symptoms. Seven significant factors associated with increased levels of anxiety, including female, resident in urban regions, emotion-focused coping style. Nine factors associated with increased levels of depression, such as smartphone addiction (OR 1.411, 95% CI 1.099–1.180), Internet addiction (OR 1.844, 95% CI 1.209–2.811), and resident in Hubei province (OR 3.107, 95% CI 1.252–7.708). Two additional factors associated with decreased levels of depressive symptoms: hours spend on Internet per day before the epidemic (OR 0.652, 95% CI 0.609–0.697) and tendency to apply problem-focused coping style (OR 0.937, 95% CI 0.923–0.951).
: Our findings indicate that the COVID-19 outbreak has had a significant psychosocial impact on children and adolescents. Findings of current levels of anxiety and depression not only highlight the need to address emotional distress for children and adolescents during the epidemic but also provide researchers with scientific fundamentals to formulate targeted interventions based on the significant influencing factors.
The dynamics, duration, and nature of immunity produced during SARS-CoV-2 infection are still unclear. Here, we longitudinally measured virus-neutralising antibody, specific antibodies against the ...spike (S) protein, receptor-binding domain (RBD), and the nucleoprotein (N) of SARS-CoV-2, as well as T cell responses, in 25 SARS-CoV-2-infected patients up to 121 days post-symptom onset (PSO). All patients seroconvert for IgG against N, S, or RBD, as well as IgM against RBD, and produce neutralising antibodies (NAb) by 14 days PSO, with the peak levels attained by 15-30 days PSO. Anti-SARS-CoV-2 IgG and NAb remain detectable and relatively stable 3-4 months PSO, whereas IgM antibody rapidly decay. Approximately 65% of patients have detectable SARS-CoV-2-specific CD4
or CD8
T cell responses 3-4 months PSO. Our results thus provide critical evidence that IgG, NAb, and T cell responses persist in the majority of patients for at least 3-4 months after infection.
Articular cartilage repair is a critical issue in osteoarthritis (OA) treatment. The insulin-like growth factor (IGF) signaling pathway has been implicated in articular cartilage repair. IGF-1 is a ...member of a family of growth factors that are structurally closely related to pro-insulin and can promote chondrocyte proliferation, enhance matrix production, and inhibit chondrocyte apoptosis. Here, we reviewed the role of IGF-1 in cartilage anabolism and catabolism. Moreover, we discussed the potential role of IGF-1 in OA treatment. Of note, we summarized the recent progress on IGF delivery systems. Optimization of IGF delivery systems will facilitate treatment application in cartilage repair and improve OA treatment efficacy.
Achieving rapid and effective hemostasis on irregularly shaped, non‐compressible visceral, and high‐pressure arterial bleeding wounds remains a critical clinical challenge. Herein, an ultrafast ...self‐gelling and wet adhesive polyethyleneimine/polyacrylic acid/quaternized chitosan (PEI/PAA/QCS) powder is reported as the hemostatic material and wound dressing. PEI/PAA/QCS powder deposited on bleeding wounds can rapidly absorb a large amount of blood to concentrate coagulation factors. Meanwhile, the powder can form an adhesive hydrogel in situ within 4 s upon hydration to form a pressure‐resistant physical barrier. Furthermore, PEI/PAA/QCS hydrogels can aggregate blood cells and platelets to enhance hemostasis. Depositing PEI/PAA/QCS powder on various bleeding wounds, including at the liver and heart, high‐pressure femoral artery and tail vein of rats, arrests the bleeding around 10 s with no rebleeding after ten minutes. Excellent hemostasis of PEI/PAA/QCS powder is further demonstrated against massive hemorrhage in porcine spleen and liver in vivo, which are non‐compressible organs with abundant blood supply. In addition, the powder can be used as a wound dressing to promote the healing of the full‐thickness skin wounds. The advantages of PEI/PAA/QCS powder including rapid and effective hemostasis, effective wound healing, easy usage, low cost, and adaptability to fit complex target sites make it a promising biomaterial for surgical applications.
Polyethyleneimine/polyacrylic acid/quaternized chitosan (PEI/PAA/QCS) powder deposited on bleeding wounds not only can rapidly absorb a large amount of blood to concentrate coagulation factors, but also can form a stable pressure‐resistant physical barrier on the wounds. In addition, the PEI/PAA/QCS powder‐derived hydrogels can aggregate blood cells and platelets to enhance hemostasis. Therefore, the PEI/PAA/QCS can achieve rapid and effective hemostasis in various complex wounds.
Keeping mammalian gastrointestinal (GI) tract communities in balance is crucial for host health maintenance. However, our understanding of microbial communities in the GI tract is still very limited. ...In this study, samples taken from the GI tracts of C57BL/6 mice were subjected to 16S rRNA gene sequence-based analysis to examine the characteristic bacterial communities along the mouse GI tract, including those present in the stomach, duodenum, jejunum, ileum, cecum, colon and feces. Further analyses of the 283,234 valid sequences obtained from pyrosequencing revealed that the gastric, duodenal, large intestinal and fecal samples had higher phylogenetic diversity than the jejunum and ileum samples did. The microbial communities found in the small intestine and stomach were different from those seen in the large intestine and fecal samples. A greater proportion of Lactobacillaceae were found in the stomach and small intestine, while a larger proportion of anaerobes such as Bacteroidaceae, Prevotellaceae, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae were found in the large intestine and feces. In addition, inter-mouse variations of microbiota were observed between the large intestinal and fecal samples, which were much smaller than those between the gastric and small intestinal samples. As far as we can ascertain, ours is the first study to systematically characterize bacterial communities from the GI tracts of C57BL/6 mice.
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