Circulating serum fibroblast growth factor 21 as risk and prognostic biomarker of retinal artery occlusion

To evaluate the predictive and prognostic value of fibroblast growth factor 21 (FGF21) levels in retinal artery occlusion (RAO) patients. In this case-control study, serum FGF21 levels were detected by using the ELISA method. Multivariable logistic regression analyses were performed to evaluate the significance of FGF21 in assessing the risk of developing RAO and its impact on vision and concurrent ischemic stroke. Compared with control group, serum FGF21 levels were significantly higher (median [IQR] = 230.90[167.40,332.20] pg/ml) in RAO patients. Multivariate logistic regression analysis showed that elevated serum FGF21 levels were associated with a higher risk of RAO occurrence (P = 0.025, OR [95%CI] = 9.672 [2.573, 36.359]) after adjustment for multiple confounding factors. Higher serum FGF21 levels were negatively associated with visual acuity improvement (P = 0.029, OR [95%CI] = 0.466[0.235, 0.925]) and positively correlated with concurrent ischemic stroke (P = 0.04, OR [95% CI] = 1.944[1.029, 3.672]) in RAO patients. Elevated serum FGF21 levels could promote the development of RAO and indicate worse visual prognosis and increase the risk of concurrent ischemic stroke, which might help clinicians early diagnose and treat RAO patients.

MiR-145-5p overexpression rejuvenates aged adipose stem cells and accelerates wound healing

Adipose-derived stem cells (ADSCs) have been widely applied in translational and regenerative medicine. During aging, there is a recognized functional decline in ADSCs, which compromises their therapeutic effectiveness. Currently, the mechanisms of aging-induced stem cell dysfunction remain unclear, hence there is a need to elucidate these mechanisms and propose strategies for reversing this functional impairment. In this study, we found that ADSCs isolated from old donors (O-ADSCs) presented inferior phenotypes and decreased miR-145-5p levels compared to those from young donors (Y-ADSCs). To interrogate the role of miR-145-5p in ADSCs, gain- and loss-of-function assays were performed. The results indicated that miR-145-5p overexpression in O-ADSCs promoted cellular proliferation and migration, while reducing cell senescence. Further study demonstrated that miR-145-5p could regulate ADSCs function by targeting bone morphogenetic protein binding endothelial cell precursor-derived regulator (BMPER), which is a crucial modulator in angiogenesis. Moreover, in vivo experiments showed that miR-145-5p-overexpressing O-ADSCs accelerated wound healing by promoting wound re-epithelialization and angiogenesis. Collectively, this study indicates that miR-145-5p works as a positive regulator for optimizing O-ADSCs function, and may be a novel therapeutic target for restoring aging-associated impairments in stem cell function.

Virus-Like Particles Based on the Novel Goose Parvovirus (NGPV) VP2 Protein Protect Ducks against NGPV Challenge

Novel goose parvovirus (NGPV), a genetic variant of goose parvovirus, has been spreading throughout China since 2015 and mainly infects ducklings with the symptoms of growth retardation, beak atrophy, and protruding tongue, leading to huge economic losses every year. A safe and effective vaccine is urgently needed to control NGPV infection. In this study, virus-like particles (VLPs) of NPGV were assembled and evaluated for their immunogenicity. The VP2 protein of NGPV was expressed in Spodoptera frugiperda insect cells using baculovirus as vector. The VP2 protein was efficiently expressed in the nucleus of insect cells, and the particles with a circular or hexagonal shape and a diameter of approximately 30 nm, similar to the NGPV virion, were observed using transmission electron microscopy (TEM). The purified particles were confirmed to be composed of VP2 using western blot and TEM, indicating that the VLPs of NGPV were successfully assembled. Furthermore, the immunogenicity of the VLPs of NGPV was evaluated in Cherry Valley ducks. The level of NGPV serum antibodies increased significantly at 1-4 weeks post-immunization. No clinical symptoms or deaths of ducks occurred in all groups after being challenged with NGPV at 4 weeks post-immunization. There was no viral shedding in the immunized group. However, viral shedding was detected at 3-7 days post-challenge in the non-immunized group. Moreover, VLPs can protect ducks from histopathological lesions caused by NGPV and significantly reduce viral load in tissue at 5 days post-challenge. Based on these findings, NGPV VLPs are promising candidates for vaccines against NGPV.

The Linkage-Moderated Covalent Organic Frameworks with C=N and NN on Charge Transfer Kinetics Towards the Robust Photocatalytic Hydrogen Activity

Since the linkages structured in covalent organic frameworks (COFs) usually impact the charge transfer behavior during photocatalytic hydrogen evolution reaction (pc-HER), linkage dependence on charge transfer kinetics should be further claimed. Herein, COFs with N-based linkages and pyrene-based building nodes are constructed to enable us to obtain new clues about the charge transfer behavior and evolution tendency relevant to linkages at a molecular level for pc-HER. It is demonstrated that photo-excited electrons preferably move to the N sites in C=N linkage for pc-HER and are trapped around NN linkage as well. A high electron transfer rate does not point to high photocatalytic activity directly, while a small difference between the electron transfer rate and electron recombination rate ΔkCT - CR predicts the inefficiency of charge transfer in Azod-COFs. Contrarily, large value of ΔkCT - CR in the case of Benzd-COFs, demonstrats an unimpeded charge transfer process to result in boosted pc-HER rate (2027.3 µmol h-1 g-1 ). This work offers a prominent strategy for the reasonable design of efficient photocatalysts at the molecular level for structural regulation and achieves an efficient charge transfer process for the pc-HER process.

C-terminal truncation of the hemagglutinin-neuraminidase (HN) protein enhances the virulence and immunogenicity of Newcastle disease virus (NDV) vaccine strain V4

The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) is a multifunctional protein with receptor recognition ability that plays an important role in the infection of cells by NDV. An alignment of NDV HN protein sequences of different genotypes showed that vaccine strains of NDV, such as the LaSota strain, generally have an HN protein of 577 amino acids. In comparison, the HN protein of the V4 strain has 616 amino acids, with 39 more amino acids at the C-terminus. In this study, we generated a recombinant NDV (rNDV) with a 39-amino-acid truncation at the HN C-terminus based on the full-length cDNA clone of the V4 strain. This rNDV, named rV4-HN-tr, displayed thermostability similar to that of the parental V4 strain. However, growth kinetics and pathogenicity analysis suggested that rV4-HN-tr is more virulent than the V4 strain. Notably, the C-terminus of HN affected the ability of the virus to adsorb onto cells. Structural predictions further suggested that the C-terminus of HN may obstruct the sialic acid binding site. Immunization of chickens with rV4-HN-tr induced a 3.5-fold higher level of NDV-specific antibodies than that obtained with the V4 strain and provided 100% immune protection against NDV challenge. Our study suggests that rV4-HN-tr is a thermostable, safe, and highly efficient vaccine candidate against Newcastle disease.

Application of Nanocellulose-Based Aerogels in Bone Tissue Engineering: Current Trends and Outlooks

The complex or compromised bone defects caused by osteomyelitis, malignant tumors, metastatic tumors, skeletal abnormalities, and systemic diseases are difficult to be self-repaired, leading to a non-union fracture. With the increasing demands of bone transplantation, more and more attention has been paid to artificial bone substitutes. As biopolymer-based aerogel materials, nanocellulose aerogels have been widely utilized in bone tissue engineering. More importantly, nanocellulose aerogels not only mimic the structure of the extracellular matrix but could also deliver drugs and bioactive molecules to promote tissue healing and growth. Here, we reviewed the most recent literature about nanocellulose-based aerogels, summarized the preparation, modification, composite fabrication, and applications of nanocellulose-based aerogels in bone tissue engineering, as well as giving special focus to the current limitations and future opportunities of nanocellulose aerogels for bone tissue engineering.

Exosomes derived from oral squamous cell carcinoma tissue accelerate diabetic wound healing

It is a widespread and difficult problem that refractory diabetic wounds have a poor local environment and prolonged inflammatory irritation. Tumor cell-derived exosomes play an important role in the development of tumors, as they can promote tumor cell proliferation, migration, and invasion and enhance tumor cell activity. However, tumor tissue-derived exosomes have been less studied, and it is unclear how they affect wound healing. In this study, we extracted tissue-derived exosomes from human oral squamous carcinoma and paracancerous tissue by ultracentrifugation, size exclusion chromatography and ultrafiltration and performed exosome characterization. In vitro, the oral squamous cell carcinoma tissue-derived exosomes (OSCC Ti-Exos) promoted the proliferation and migration of endothelial cells, keratinocytes, and fibroblasts. In addition, in vivo experiments showed that the OSCC Ti-Exos accelerated the healing of diabetic wounds and were safe in mice. In contrast, there was no promoting effect of paracancerous tissue-derived exosomes either in vivo or in vitro. In conclusion, OSCC Ti-Exos promoted the healing of diabetic wounds, demonstrated preliminary biosafety in mice and have promise as therapeutic applications.