Rapid development and mass production of SARS-CoV-2 neutralizing chicken egg yolk antibodies with protective efficacy in hamsters.

Despite the record speed of developing vaccines and therapeutics against the SARS-CoV-2 virus, it is not a given that such success can be secured in future pandemics. In addition, COVID-19 vaccination and application of therapeutics remain low in developing countries. Rapid and low cost mass production of antiviral IgY antibodies could be an attractive alternative or complementary option for vaccine and therapeutic development. In this article, we rapidly produced SARS-CoV-2 antigens, immunized hens and purified IgY antibodies in 2 months after the SARS-CoV-2 gene sequence became public. We further demonstrated that the IgY antibodies competitively block RBD binding to ACE2, neutralize authentic SARS-CoV-2 virus and effectively protect hamsters from SARS-CoV-2 challenge by preventing weight loss and lung pathology, representing the first comprehensive study with IgY antibodies. The process of mass production can be easily implemented in most developing countries and hence could become a new vital option in our toolbox for combating viral pandemics. This study could stimulate further studies, optimization and potential applications of IgY antibodies as therapeutics and prophylactics for human and animals.

Exploring m6A-linked aging genes in osteoarthritis and broad cancer spectrum: Prospects for diagnostic and therapeutic advancements.

Osteoarthritis (OA) is a prevalent degenerative joint disease that significantly impacts individuals and healthcare systems worldwide. However, the exploration of N6-methyladenosine (m6A)-related aging genes in OA pathogenesis remains largely underexplored. This study aimed to elucidate the role of m6A-related aging genes in OA and to develop a robust diagnostic model based on their expression profiles. Leveraging publicly available gene expression datasets, we conducted consensus clustering to categorize OA into distinct subtypes, guided by the expression patterns of m6A-related aging genes. Utilizing XGBoost, a cutting-edge machine learning approach, we identified key diagnostic genes and constructed a predictive model. Our investigation extended to the immune functions of these genes, shedding light on potential therapeutic targets and underlying regulatory mechanisms. Our analysis unveiled specific OA subtypes, each marked by unique expression profiles of m6A-related aging genes. We pinpointed a set of pivotal diagnostic genes, offering potential therapeutic avenues. The developed diagnostic model exhibited exceptional capability in distinguishing OA patients from healthy controls. To corroborate our computational findings, we performed quantitative real-time polymerase chain reaction analyses on two cell lines: HC-OA (representing adult osteoarthritis cells) and C-28/I2 (representative of normal human chondrocytes). The gene expression patterns observed were consistent with our bioinformatics predictions, further validating our initial results. In conclusion, this study underscores the significance of m6A-related aging genes as promising biomarkers for diagnosis and prognosis, as well as potential therapeutic targets in OA. Although these findings are encouraging, further validation and functional analyses are crucial for their clinical application.

Rapid development and mass production of SARS-CoV-2 neutralizing chicken egg yolk antibodies with protective efficacy in hamsters

Despite the record speed of developing vaccines and therapeutics against the SARS-CoV-2 virus, it is not a given that such success can be secured in future pandemics. In addition, COVID-19 vaccination and application of therapeutics remain low in developing countries. Rapid and low cost mass production of antiviral IgY antibodies could be an attractive alternative or complementary option for vaccine and therapeutic development. In this article, we rapidly produced SARS-CoV-2 antigens, immunized hens and purified IgY antibodies in 2 months after the SARS-CoV-2 gene sequence became public. We further demonstrated that the IgY antibodies competitively block RBD binding to ACE2, neutralize authentic SARS-CoV-2 virus and effectively protect hamsters from SARS-CoV-2 challenge by preventing weight loss and lung pathology, representing the first comprehensive study with IgY antibodies. The process of mass production can be easily implemented in most developing countries and hence could become a new vital option in our toolbox for combating viral pandemics. This study could stimulate further studies, optimization and potential applications of IgY antibodies as therapeutics and prophylactics for human and animals.

Evaluation of natural protein-based nanofiber composite photocrosslinking hydrogel for skin wound regeneration.

Protein based photocrosslinking hydrogels with nanofiber dispersions were reported to be an effective wound dressing. In this study, two kinds of protein (gelatin and decellularized dermal matrix) were modified to obtain GelMA and ddECMMA, respectively. Poly(ε-caprolactone) nanofiber dispersions (PCLPBA) and thioglycolic acid-modified chitosan (TCS) were added into GelMA solution and ddECMMA solution, respectively. After photocrosslinking, four kinds of hydrogel (GelMA, GTP4, DP and DTP4) were fabricated. The hydrogels showed excellent physico-chemical property, biocompatibility and negligible cytotoxicity. When applied on the full-thickness cutaneous deficiency of SD rats, hydrogel treated groups exhibited an enhanced wound healing effect than Blank group. Besides, the histological staining of H&E and Masson's showed that hydrogels groups with PCLPBA and TCS (GTP4 and DTP4) improved wound healing. Furthermore, GTP4 group performed better healing effect than other groups, which had great potential in skin wound regeneration.

On the development of modular polyurethane-based bioelastomers for rapid hemostasis and wound healing.

Massive hemorrhage may be detrimental to the patients, which necessitates the advent of new materials with high hemostatic efficiency and good biocompatibility. The objective of this research was to screen for the effect of the different types of bio-elastomers as hemostatic dressings. 3D loose nanofiber sponges were prepared; PU-TA/Gel showed promising potential. Polyurethane (PU) was synthesized and electrospun to afford porous sponges, which were crosslinked with glutaraldehyde (GA). FTIR and 1H-NMR evidenced the successful synthesis of PU. The prepared PU-TA/Gel sponge had the highest porosity and water absorption ratio. Besides, PU-TA/Gel sponges exhibited cytocompatibility, negligible hemolysis and the shortest clotting time. PU-TA/Gel sponge rapidly induced stable blood clots with shorter hemostasis time and less bleeding volume in a liver injury model in rats. Intriguingly, PU-TA/Gel sponges also induced good skin regeneration in a full-thickness excisional defect model as revealed by the histological analysis. These results showed that the PU-TA/Gel-based sponges may offer an alternative platform for hemostasis and wound healing.

Hofmeister effect-enhanced gelatin/oxidized dextran hydrogels with improved mechanical properties and biocompatibility for wound healing.

Compared with other types of hydrogels, natural derived hydrogels possess intrinsic advantages of degradability and biocompatibility. However, due to the low mechanical strength, their potential applications in biomedical areas are limited. In this study, Hofmeister effect-enhanced gelatin/oxidized dextran (Gel/O-Dex) hydrogels were designed with improved mechanical properties and biocompatibility to accelerate wound healing. Gel and O-Dex were chemically crosslinked through Schiff base reaction of aldehyde and amino groups. After soaking in kosmotrope solutions physical crosslinking domains were induced by Hofmeister effect including α-helix structures, hydrophobic interaction regions and helical junction zones among Gel molecular chains. The type of anions played different influence on the properties of hydrogels, which was consistent with the order of Hofmeister series. Particularly, H2PO4- treated hydrogels showed enhanced mechanical strength and fatigue resistance superior to that of Gel/O-Dex hydrogels. The underlying mechanism was that the physical crosslinking domains sustained additional mechanical stress and dissipated energy through cyclic association and dissociation process. Furthermore, Hofmeister effect only induced polymer chain entanglements without triggering any chemical reaction. Due to Hofmeister effect of H2PO4- ions, aldehyde groups were embedded in the center of entangled polymer chains that resulted in better biocompatibility. In the full-thickness skin defects of SD rats, Hofmeister effect-enhanced Gel/O-Dex hydrogels by H2PO4- ions accelerated wound healing and exhibited better histological morphology than ordinary hydrogels. Therefore, Hofmeister effect by essential inorganic anions is a promising method of improving mechanical properties and biocompatibility of natural hydrogels to promote medical translation in the field of wound healing from bench to clinic. STATEMENT OF SIGNIFICANCE: Hofmeister effect enhanced hydrogel mechanical properties in accordance with the order of Hofmeister series through physical crosslinking that induced α-helix structures, hydrophobic interaction regions and helical junction zones among Gel molecular chains. Due to the Hofmeister effect of H2PO4- ions, aldehyde groups were embedded in the center of entangled polymer chains that resulted in better biocompatibility. Hofmeister effect-enhanced Gel/O-Dex hydrogels through H2PO4- ions accelerated wound healing and exhibited better histological morphology than ordinary hydrogels. Therefore, Hofmeister effect by essential inorganic anions is a promising method to improve mechanical properties and biocompatibility of natural hydrogels for their medical applications..

Hybrid Nanofibrous Composites with Anisotropic Mechanics and Architecture for Tendon/Ligament Repair and Regeneration.

Rupture of tendons and ligaments (T/L) is a major clinical challenge due to T/L possess anisotropic mechanical properties and hierarchical structures. Here, to imitate these characteristics, an approach is presented by fabricating hybrid nanofibrous composites. First, hybrid fiber-reinforced yarns are fabricated via successively electrospinning poly(L-lactide-co-ε-caprolactone) (PLCL) and gelatin (Ge) nanofibers onto polyethylene terephthalate (PET) fibers to improve biodurability and biocompatibility. Then, by comparing different manufacturing methods, the knitted structure succeeds in simulating anisotropic mechanical properties, even being stronger than natural ligaments, and possessing comfort compliance superior to clinically used ligament advanced reinforcement system (LARS) ligament. Moreover, after inoculation with tendon-derived stem cells and transplantation in vivo, hybrid nanofibrous composites are integrated with native tendons to guide surrounding tissue ingrowth due to the highly interconnected and porous structure. The knitted hybrid nanofibrous composites are also ligamentized and remodeled in vivo to promote tendon regeneration. Specifically, after the use of optimized anisotropic hybrid nanofibrous composites to repair tendon, the deposition of tendon-associated extracellular matrix proteins is more significant. Thus, this study indicates a strategy of manufacturing anisotropic hybrid nanofibrous composites with superior mechanical properties and good histocompatibility for clinical reconstruction.

A high-throughput analytical method for multiple DNA targets based on microdroplet PCR coupled with DGGE.

We developed a novel approach to analyze multiple DNA targets based on microdroplet PCR coupled with denaturing gradient gel electrophoresis (MPDG) to achieve high-throughput detection of biological samples. The target DNAs were preamplified using specific primers. Subsequently, the preamplified products were separated into individual microreactors for parallel amplification with high efficiency, avoiding the interference of different primers and templates, and preventing inconsistent amplification efficiency and non-specific amplification. The final products were analyzed using denaturing gradient gel electrophoresis (DGGE). Using genetically modified (GM) maize as samples, the MPDG method could be used for the simultaneous detection of three DNA targets with an absolute limit of detection of 0.5% (w/w), with no cross reaction with other non-GM samples. The simulated sample assay of MPDG suggested that the method is suitable for practical application. The MPDG approach, with high sensitivity and specificity, could play a crucial role in the field of nucleic acid detection.

Rapid and Severe Idiopathic Aseptic Necrosis of the Contralateral Femoral Head after Unilateral Total Hip Arthroplasty.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is a multifactorial disease, and agnogenic ONFH, otherwise known as idiopathic ONFH, is rare in clinic. Idiopathic ONFH that exhibits severe necrosis and progresses extremely rapidly is called rapidly destructive hip disease (RDHD). RDHD greatly affects patients but is rarely reported in clinical practice and literature. CASE PRESENTATION: In this study, a 64-year-old male patient with complete collapse and necrosis of the right femoral head complicated with severe bone destruction at 10 months after left total hip arthroplasty (THA) was reported. The period from the intact structure of the right femoral head to the first discovery of its complete collapse, according to imaging results, was 7 months. The duration from the occurrence of symptoms in the right hip joint to the first discovery of complete collapse and necrosis of the femoral head was only 5 months. At present, the cause has not been determined based on medical history, symptoms, signs, imaging evaluation results, laboratory examination results, and pathological examination results, though it has been identified as severe idiopathic aseptic necrosis of the femoral head with rapid progression, or RDHD. Finally, right THA was performed, and a good outcome was observed in the patient at present. CONCLUSIONS: As a rare hip joint disease, RDHD greatly influences the normal life of patients. RDHD of the contralateral side after unilateral THA is even scarcer. Left THA may be one of the important factors accelerating the necrosis of the right femoral head. Hopefully, with this case report, more attention will be paid to the contralateral hip joint in patients undergoing unilateral THA by clinicians and rehabilitation physicians, and a clinical reference will be provided for the research on RDHD.

No difference in postoperative efficacy and safety between autograft and allograft in anterior cruciate ligament reconstruction: a retrospective cohort study in 112 patients.

Background: Arthroscopic anterior cruciate ligament reconstruction (ACLR) is the best treatment choice for returning to pre-injury activities following ACL rupture. Although allografts are considered an effective alternative to autografts, there is still controversy regarding the safety and effectiveness of this procedure, especially concerning the risk of postoperative infection and disease transmission. The purpose of this study was to compare the efficacy outcomes and safety between allografts and autografts in primary ACLR. Methods: The retrospective analysis involved 112 patients (58 patients received allogeneic tendons and 54 patients received autologous hamstring tendons) who underwent primary ACLR. All patients were followed up and evaluated on admission and at 1 week, 3 months, 6 months, and 1 year postoperatively. The efficacy outcome of the ACLR was evaluated by International Knee Documentation Committee (IKDC) score and physical examinations (Lachman test, anterior drawer test, and pivot shift test). The safety outcome of allografts and autografts was compared by investigating the occurrence of postoperative complications, including postoperative inflammation and potential disease transmission. The benefits of each operation for surgeons and patients were also analyzed, including the length of surgical incision and operative time. Results: There was no significant difference in the demographic and clinical characteristics between the allograft and autograft groups. The two cohorts proved to be similar in terms of the acute or chronic nature of the cruciate ligament and the incidence of concomitant meniscal surgery. Arthroscopic ACLR was performed in all patients. The physical examinations were all positive before surgery and negative immediately after the operation. The KT-1000 and IKDC scores of two groups significantly decreased than pre-operative ones (P<0.05), but the difference between the two groups was not statistically significant (P>0.05). At final follow-up, all patients had returned to their pre-injury activities. Allografts showed no increased risk for postoperative infection or potential disease transmission relative to autografts. Conclusions: The outcomes of reconstructed ACL with allografts were similar to those of autographs. Moreover, the safety of allografts showed to be comparable to that of autografts, especially concerning postoperative infection and disease transmission. Therefore, the surgical option should be chosen wisely according to the patient's condition.

Antibacterial, antioxidant and anti-inflammatory PLCL/gelatin nanofiber membranes to promote wound healing.

Epigallocatechin-3-O-gallate (EGCG) is a green biomedical agent for promoting wound healing, which possess excellent antibacterial, antioxidant and anti-inflammatory activities. For improving the low bioavailability challenges of EGCG in vivo, we had successful created a low-cost and simple wound dressing Poly (L-Lactic-co-caprolactone) (PLCL)/Gelatin/EGCG/Core-shell nanofiber membrane (PGEC) with drug sustained release capacity through coaxial electrospinning technology. In vitro experimental indicated that the core-shell structure wound dressing had excellent biocompatibility, antibacterial and antioxidant ability, which could support cell viability and proliferation, encourage re-epithelialization during the healing process, inhibit subsequent wound infection and thus promote wound regeneration. In vivo experimental demonstrated that PGEC wound dressing could promote wound healing, the histological results further demonstrated that PGEC not only facilitated early wound closure but also influenced cellular differentiation and tissue organization. Meanwhile, PGEC had excellent hemostatic ability. Taken all together, we believed that the PGEC wound dressing, which could localize delivery of EGCG, had high potential clinical application for promoting wound healing, hemostasis or other related clinical applications in the future.

Role of the Alarmin S100A9 protein in inducing Achilles tendinopathy in rats.

BACKGROUND: This study aimed to investigate the correlation between the Alarmin S100A9 protein and Achilles tendinopathy (AT), and to reveal the role of this protein in inducing AT. METHODS: In this study, 40 male Sprague-Dawley rats were randomly divided into four groups: Control group (received no treatment), Injury group (Achilles tendon tissues were cut intraoperatively), S100A9 group (received a subcutaneous injection of rhS100A9 solution), and S100A9 + Paquinimod group [received a subcutaneous injection of rhS100A9 and Paquinimod (1:1 ratio) into the Achilles tendon]. At 1 week postoperatively, the four groups of rats were euthanized, and the Achilles tendon tissues were isolated for histological staining, immunohistochemistry (IHC), immunofluorescence, Sirius Red (SR) staining, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. RESULTS: Compared with both the Control and S100A9 + Paquinimod groups, the Injury and S100A9 groups exhibited higher expression levels of S100A9 protein, matrix metalloproteinase-3 (MMP-3), and inflammatory factors. Regarding histomorphology [hematoxylin-eosin (HE) staining and Safranin O/fast green (SOFG; fast green and Safranin) training], the Achilles tendon tissues in the Injury and S100A9 groups showed AT-like changes, and the fibers were extremely disorderly, non-bundled, and ruptured, and some nuclei were spindles. As for collagen (Col) remodeling, a large number of fresh collagen fibers had formed, the amounts of Col-I and Col-II were lower, and a large quantity of Col-III was present. Additionally, a large number of tendon cells had died in both the Injury and S100A9 groups. CONCLUSIONS: This study showed that Alarmin S100A9 can induce AT-like morphological changes and local inflammatory reactions, trigger collagen fiber remodeling and tendon cell apoptosis, and ultimately induce AT.

Establishment of a porcine parvovirus (PPV) LAMP visual rapid detection method.

Porcine parvovirus (PPV) is one of the major causes of reproductive pig disease. Due to its serious nature, wide spread and consequent great damage to the swine industry, an effective, rapid and convenient method for its detection is needed. A loop-mediated isothermal amplification (LAMP) assay was established to detect PPV infection. Two pairs of primers were specifically designed to recognize the six different sequences of open reading frame1 (ORF1) gene. The optimized LAMP program was as follows: 50 min at 59 °C followed by 3 min at 80 °C.The amplified products were analyzed both by visual inspection after staining with SYBR Green I dye and by conventional agarose gel electrophoresis. Both methods showed the same sensitivity. The limit of detection (LOD) for PPV by LAMP was 10 copies, which is 100-fold lower than conventional PCR. Our LAMP assay did not cross-react with other viruses. We used the established LAMP system to test 1100 field samples and detected 660 positives. The LAMP detection method for PPV represents a visual, sensitive and rapid assay which can detect the virus in the field, offering an attractive alternative for the PPV detection methods currently in use.

A novel emulsion PCR method coupled with fluorescence spectrophotometry for simultaneous qualitative, quantitative and high-throughput detection of multiple DNA targets.

We constructed and validated a novel emulsion PCR method combined with fluorescence spectrophotometry (EPFS) for simultaneous qualitative, quantitative and high-throughput detection of multiple DNA targets. In a single reaction set, each pair of primers was labeled with a specific fluorophore. Through emulsion PCR, a target DNA was amplified in droplets that functioned as micro-reactors. After product purification, different fluorescent-labeled DNA products were qualitatively analyzed by the fluorescent intensity determination. The sensitivity and specificity of the system was examined using four kinds of genetically modified (GM) maize. The qualitative results revealed high specificity and sensitivity of 0.5% (w/w). In addition, the quantitative results revealed that the absolute limit of detection was 103 copies, showing good repeatability. Moreover, the reproducibility assays were further performed using four foodborne pathogenic bacteria to further evaluate the applicability of the system. Consequently, the same qualitative, quantitative and high-throughput results were confirmed with the four GM maize. To sum up, the new EPFS system is the first analytical technology of this kind that enables simultaneous qualitative, quantitative and high-throughput analysis of multiple genes.

Rapid visual detection of lily mottle virus using a loop-mediated isothermal amplification method.

Lily mottle virus (LMoV; genus Potyvirus, family Potyviridae) infects plants of the genus Lilium, causing a reduction in flower and bulb quality. A rapid and sensitive loop-mediated isothermal amplification (LAMP) assay was developed to detect the coat protein gene of LMoV. This LAMP method was highly specific for LMoV, with no cross-reaction with other lily viruses. The sensitivity of LMoV using the LAMP assay was 100 times more sensitive than that using conventional polymerase chain reaction. A reverse transcription LAMP (RT-LAMP) was then successfully applied to detect LMoV RNA. The newly established LAMP and one-step RT-LAMP provide an alternative method for detecting LMoV in lily plants.