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Aflatoxin B1 (AFB1), a highly toxic mycotoxin, always contaminated in a variety of agricultural products. Camelid variable domain of heavy chain antibody (VHH) is a noteworthy reagent in immunoassay, owing to its excellent characteristics. Immunization of camelid animals is a straightforward strategy to produce VHHs. In this study, to avoid the dependence on the large animals, the camelized, murine antibody (cVHs) against AFB1 was prepared in vitro based on the identities between murine VH and camelid VHH and then to develop an immunoassay for AFB1. A murine anti-AFB1 VH fragment (VH-2E6) was selected for camelization through replacement of conserved hydrophobic residues in framework region 2 (FR2) (cVH-FR2), point mutation at position 103 in the FR4 region (cVH-103), and CDR3-grafted with a high AFB1-affinity VHH (cVH-Nb26). The cVH-Nb26 had a yield of 5 mg/L as refolded protein expressed from Escherichia coli and 10 mg/L expressed from Pichia pastoris. Compared with anti-AFB1 single-chain fragment variable (scFv) 2E6, cVH-Nb26 performed more than 20-fold enhancement of AFB1-binding interactions. Although the AFB1-affinity of cVH-Nb26 cannot meet the application requirement in the present form, our study provides effective strategies for preparation of camelized antibody in vitro, which could be a promising immunoreagent for AFB1 detection.

To date, severe bone defects remain a significant challenge to the quality of life. All clinically used bone grafts have their limitations. Bone tissue engineering offers the promise of novel bone graft substitutes. Various biomaterial scaffolds are fabricated by mimicking the natural bone structure, mechanical properties, and biological properties. Among them, gelatin methacryloyl (GelMA), as a modified natural biomaterial, possesses a controllable chemical network, high cellular stability and viability, good biocompatibility and degradability, and holds the prospect of a wide range of applications. However, because they are hindered by their mechanical properties, degradation rate, and lack of osteogenic activity, GelMA hydrogels need to be combined with other materials to improve the properties of the composites and endow them with the ability for osteogenesis, vascularization, and neurogenesis. In this paper, we systematically review and summarize the research progress of GelMA composite hydrogel scaffolds in the field of bone defect repair, and discuss ways to improve the properties, which will provide ideas for the design and application of bionic bone substitutes. [ABSTRACT FROM AUTHOR]

Background: Tooth loss is closely related to cognitive impairment, especially affecting cognitive functions involving hippocampus. The most well‐known function of the hippocampus is learning and memory, and the mechanism behind is neuroplasticity, which strongly depends on the level of brain‐derived neurotrophic factor (BDNF). While research has delved into the possible mechanisms behind the loss of teeth leading to cognitive dysfunction, there are few studies on the plasticity of sensory neural pathway after tooth loss, and the changes in related indicators of synaptic plasticity still need to be further explored. Methods: In this study, the bilateral maxillary molars were extracted in Sprague–Dawley rats of two age ranges (young and middle age) to establish occlusal support loss model; then, the spatial cognition was tested by Morris Water Maze (MWM). Quantitative real‐time PCR (qPCR) and Western Blotting (WB) were used to detect BDNF, AKT, and functional proteins (viz., PSD95 and NMDAR) of hippocampal synapses. Golgi staining was used to observe changes in ascending nerve pathway. IF was used to confirm the location of BDNF and AKT expressed in hippocampus. Results: MWM showed that the spatial cognitive level of rats dropped after occlusal support loss. qPCR, WB, and IF suggested that the BDNF/AKT pathway was down‐regulated in the hippocampus. Golgi staining showed the neurons of ascending sensory pathway decreased in numbers. Conclusion: Occlusal support loss caused plastic changes in ascending nerve pathway and induced cognitive impairment in rats by down‐regulating BDNF and synaptic plasticity. [ABSTRACT FROM AUTHOR]

Study objective: During cesarean section, hypotension is a frequent side effect of spinal anesthesia. As a sitting or lateral position is required for spinal anesthesia performance, which of these two positions is more likely to cause intraoperative nausea, vomiting, and hypotension is still unknown. This meta-analysis compared the effects of these two positions on maternal hemodynamics and intraoperative nausea and vomiting. Design: Systematic review and meta-analysis Setting: Operating room Patients: This study included 803 patients from 12 randomized controlled trials (RCTs). Interventions: Neuraxial anesthesia in sitting position vs. lateral position. Measurements: We chose RCTs comparing the effects of spinal anesthesia in the sitting and lateral positions on maternal hemodynamics by thoroughly searching PubMed, Embase, the Cochrane Library, and the Web of Science for articles published from database inception until October 31, 2022. The Cochrane Handbook was used to assess the methodological quality of each RCT; the results were analyzed using RevMan 5.4 software; and the Egger test was used to assess publication bias. Main results: 12 randomised controlled trials with 803 participants were ultimately included in the final analysis. No significant differences were observed between the two positions in terms of the incidence of hypotension(RR, 0.82; 95% CI, 0.58–1.16; P = 0.26; I2 = 66%), lowest systolic blood pressure(MD, -0.81; 95% CI, -7.38–5.75; P = 0.81; I2 = 86%), the dose of ephedrine(MD, -1.19; 95% CI, -4.91–2.52; P = 0.53; I2 = 83%), and number of parturients requiring ephedrine(RR, 0.97; 95% CI, 0.64–1.46; P = 0.88; I2 = 74%). For the incidence of intraoperative nausea and vomiting, there was no statistical difference between the two positions. Conclusion: Parturients undergoing elective cesarean section under spinal anesthesia in the sitting or lateral position experienced similar incidence of hypotension, and there were no significant differences between these two positions in terms of the amount of ephedrine administered or the number of patients needing ephedrine. In both positions, the frequency of nausea and vomiting was comparable. The ideal position for anesthesia can be chosen based on the preferences and individual circumstances of the parturient and anesthesiologist. [ABSTRACT FROM AUTHOR]

Objective: Loss of occlusal support due to tooth loss has been indicated as one of the risk factors for Alzheimer's disease. This study aimed to investigate the relationship between tooth loss and cognitive dysfunction and illustrate the role of neuroinflammation in advancing Alzheimer's disease. Materials and Methods: Male 5‐month‐old senescence‐accelerated mouse strain P8 (SAMP8) mice were divided into three groups (n = 7): the C (control), S (sham‐operated), and TL (tooth loss) groups. The Morris water maze (MWM) test was performed to assess spatial memory. Additionally, histopathological and molecular assessments of hippocampal tissues were performed. Results: The TL groups exhibited impaired spatial memory in the water maze. Tooth loss induced higher protein expression levels of the neuroinflammation cytokine interleukin‐1β (IL‐1β) in the hippocampus than in the S and C groups. Tooth loss activated the NLRP3 inflammasome and increased the expression of Caspase‐1 in the hippocampus. Conclusions: The findings indicated that tooth loss impairs cognitive function in SAMP8 mice and is closely related to the activation of NLRP3/Caspase‐1 in the hippocampus. [ABSTRACT FROM AUTHOR]

Electrical stimulation (ES) is proposed as a therapeutic solution for managing chronic wounds. However, its widespread clinical adoption is limited by the requirement of additional extracorporeal devices to power ES‐based wound dressings. In this study, a novel sandwich‐structured photovoltaic microcurrent hydrogel dressing (PMH dressing) is designed for treating diabetic wounds. This innovative dressing comprises flexible organic photovoltaic (OPV) cells, a flexible micro–electro–mechanical systems (MEMS) electrode, and a multifunctional hydrogel serving as an electrode–tissue interface. The PMH dressing is engineered to administer ES, mimicking the physiological injury current occurring naturally in wounds when exposed to light; thus, facilitating wound healing. In vitro experiments are performed to validate the PMH dressing's exceptional biocompatibility and robust antibacterial properties. In vivo experiments and proteomic analysis reveal that the proposed PMH dressing significantly accelerates the healing of infected diabetic wounds by enhancing extracellular matrix regeneration, eliminating bacteria, regulating inflammatory responses, and modulating vascular functions. Therefore, the PMH dressing is a potent, versatile, and effective solution for diabetic wound care, paving the way for advancements in wireless ES wound dressings. [ABSTRACT FROM AUTHOR]