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Natural polysaccharide hydrogels have been extensively explored for many years due to their outstanding biocompatibility and biodegradability, which are very promising candidates as artificial soft materials for biomedical applications. However, their inferior mechanical performances greatly limited their applications. Introduction of double‐network (DN) structure has been well documented to be an efficient strategy for significant improvement of the mechanical property of hydrogels. Here, recent progress of natural polysaccharide‐based DN hydrogels is reviewed from the perspective of fundamental concepts on both design rationale and preparation strategies to biomedical application in tissue repair. Retrospect of the DN‐strengthened polysaccharide hydrogels can give a deep insight into the fundamental relationship of such bio‐based hydrogels among structural design, mechanical properties and practical demands, thereby prompting their translation to clinical application prospects. [ABSTRACT FROM AUTHOR]

1,2‐Dichloropropane (1,2‐DCP) is used as an industrial solvent, insecticide fumigant and household dry cleaning product. Carcinogenicity caused by long‐term exposure to 1,2‐DCP is well established. However, the possible liver damage and related toxic mechanisms associated with acute inhalation exposure to 1,2‐DCP are rarely reported. In this study, we investigated the effects of individual and combined exposure to 1,2‐DCP and dichloromethane (DCM) on mice liver. The results showed that 1,2‐DCP significantly caused liver necrosis, possibly due to 1,2‐DCP‐induced inhibition of the mitochondrial respiratory chain complex I‐IV activities, resulting in mitochondrial dysfunction and extreme ATP consumption. Moreover, 1,2‐DCP also decreased mitochondrial defense ability by inhibiting the mitochondrial glutathione S‐transferase 1 (MGST1) activity, further aggravating liver damage. Additionally, we found that DCM co‐exposure potentially enhanced 1,2‐DCP toxicity. Our findings suggest that inhibition of mitochondrial function and MGST1 activity play critical roles in modulating 1,2‐DCP‐induced liver damage. Furthermore, our results contribute to study the new mechanism of mitochondria‐dominated signaling pathways underlying liver injury induced by 1,2‐DCP and DCM. In this study, we investigated the effects of individual and combined acute inhalation exposure to 1,2‐dichloropropane (1,2‐DCP) and dichloromethane (DCM) on mice liver. The results showed that 1,2‐DCP significantly caused liver necrosis, possibly due to 1,2‐DCP‐induced inhibition of the mitochondrial respiratory chain complex I‐IV activities, inhibiting the mitochondrial MGST1 activity, resulting in mitochondrial dysfunction and extreme ATP consumption. DCM co‐exposure potentially enhanced 1,2‐DCP toxicity. [ABSTRACT FROM AUTHOR]

Along with the rapid development of economy and urbanization, noise and air pollution are becoming major occupational health hazards in the process of industrial production. In this study, we collected data from 7293 industrial workers in China. The association between occupational exposure of noise and dust and blood pressure was investigated. Controlling for demographic variables, including sex, age, and length of service, a stepwise regression model with backward elimination was constructed. The results showed that both noise and dust decreased the level of systolic blood pressure (p < 0.001). This finding prompted the manufacturing industry to reduce noise and dust hazards and protect the occupational health of workers. Prospective studies in different populations are still required to verify the net contribution of noise and dust to the decrease in blood pressure. [ABSTRACT FROM AUTHOR]

Repair and preservation of the injured meniscus has become paramount in clinical practice. However, the complexities of various clinic stitching techniques for meniscus repair pose challenges for grassroots doctors. Hence, there is a compelling interest in innovative therapeutic strategies such as bioadhesives. An ideal bioadhesive must cure quickly in aqueous and blood environments, bind strongly, endure arthroscopic washing pressures, and degrade appropriately for tissue regeneration. Here, we present a tetra-poly (ethylene glycol) (PEG)-based hydrogel bioadhesive, boasting high biocompatibility, ultrafast gelation, facile injectable operation, and favorable mechanical strength. In view of the synergistic effects of chemical anchor and physical chain entanglement to tightly bind the meniscus, a seamless interface was formed between the surrounding meniscal tissues and hydrogels, enabling the longitudinal tear of the meniscus fused in situ to withstand large tensile force with the adhesive strength of 541.5 ± 31.4 kPa and arthroscopic washout resistance of 29.4 kPa. Superior to existing commercial adhesives, ours allows sutureless application and arthroscopic assistance, without requiring specialized clinical skills. This research is expected to significantly impact our understanding of meniscal healing and ultimately promote a simpler process for achieving functional and structural recovery in torn menisci., Competing Interests: The authors declare they have no conflicts of interest., (© 2024 The Author(s). MedComm published by Sichuan International Medical Exchange & Promotion Association (SCIMEA) and John Wiley & Sons Australia, Ltd.)

Hydrogels are extracellular-matrix-like biomimetic materials that have wide biomedical applications in tissue engineering and drug delivery. However, most hydrogels cannot simultaneously fulfill the mechanical and cell compatibility requirements. In the present study, we prepared a semi-interpenetrating network composite gel (CG) by incorporating short chain chitosan (CS) into a covalent tetra-armed poly(ethylene glycol) network. In addition to satisfying physicochemical, mechanics, biocompatibility, and cell affinity requirements, this CG easily encapsulated acetylsalicylic acid (ASA) via electrostatic interactions and chain entanglement, achieving sustained release for over 14 days and thus promoting periodontal ligament stem cell (PDLSC) proliferation and osteogenic differentiation. In vivo studies corroborated the capacity of PDLSCs and ASA-laden CG to enhance new bone regeneration in situ using a mouse calvarial bone defect model. This might be attributed to PDLSCs and host mesenchymal stem cells expressing monocyte chemoattractant protein-1, which upregulated M2 macrophage recruitment and polarization in situ , indicating its appealing potential in bone tissue engineering., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors.)

Advances in meticulous dural closure technique remain a great challenge for watertight dural closure in the aged society, because the cerebrospinal fluid (CSF) leakage after spinal surgery is often accompanied with the disgusting wound infection, meningitis and pseudomeningocele. Here, a tetra-poly (ethylene glycol) (PEG)-based hydrogel sealant is developed with collective advantages of facile operation, high safety, quick set time, easy injectability, favorable mechanical strength and powerful tissue adhesion for effective sutureless dural closure during the surgery procedure. Impressively, this tetra-PEG sealant can instantaneously adhere to the irregular tissue surfaces even in a liquid environment, and effectively prevent or block off the intraoperative CSF leakage for sutureless dural closure and dura regeneration. Together, this sutureless tetra-PEG adhesive can be utilized as a very promising alternative for high-efficient watertight dural closure of the clinical patients who incidentally or deliberately undergo the durotomy during the spinal surgery., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors.)