Collagen-based materials, renowned for their biocompatibility and minimal immunogenicity, serve as exemplary substrates in a myriad of biomedical applications. Collagen-based micro/nanogels, in particular, are valued for their increased surface area, tunable degradation rates, and ability to facilitate targeted drug delivery, making them instrumental in advanced therapeutics and tissue engineering endeavors. Although extensive reviews on micro/nanogels exist, they tend to cover a wide range of biomaterials and lack a specific focus on collagen-based materials. The current review offers an in-depth look into the manufacturing technologies, drug release mechanisms, and biomedical applications of collagen-based micro/nanogels to address this gap. First, we provide an overview of the synthetic strategies that allow the precise control of the size, shape, and mechanical strength of these collagen-based micro/nanogels by controlling the degree of cross-linking of the materials. These properties are crucial for their performance in biomedical applications. We then highlight the environmental responsiveness of these collagen-based micro/nanogels, particularly their sensitivity to enzymes and pH, which enables controlled drug release under various pathological conditions. The discussion then expands to include their applications in cancer therapy, antimicrobial treatments, bone tissue repair, and imaging diagnosis, emphasizing their versatility and potential in these critical areas. The challenges and future perspectives of collagen-based micro/nanogels in the field are discussed at the end of the review, with an emphasis on the translation to clinical practice. This comprehensive review serves as a valuable resource for researchers, clinicians, and scientists alike, providing insights into the current state and future directions of collagen-based micro/nanogel research and development.
Collagen/chemistry* ; Drug Delivery Systems/methods* ; Humans ; Tissue Engineering/methods* ; Animals ; Biocompatible Materials/chemistry*

Objective To explore the status of histone acetylation modification and their regulatory effect to hMSH2 gene and hMLH1 gene expression in acute leukemia. Methods Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the expression of hMSH2 and hMLH1 mRNA, and Western blot was used to measure the expression of histone H3, H4, HDACi, hMSH2 and hMLH1 protein in mononuclear cells of 56 acute leukemia patients and 30 healthy volunteers. The mononuclear cells of 30 acute leukemia patients were treated with histone deacetylase inhibitors trichostatin A (TSA), and measured the expression difference of histone H3, H4, HDAC1, hMSH2 and hMLH1 in the mononuclear cells treated with TSA. Results The protein expression levels of hMSH2, hMLH1, histone H3 and histone H4 in those mononuclear cells of acute leukemia patients were 0.4610±0.1211, 0.4013±0.1143, 0.4103±0.1241 and 0.4251±0.1081, respectively, which were significantly decreased comparing with those of healthy volunteers (0.9461±0. 1841, 0.996±0.2021, 0.8971±0. 1194 and 0.9513±0.1953) (t = 3.341, 3.935, 2.843 and 3.575,respectinely, P ＜0.05). The protein expression levels of HDAC1 (0.8841±0.2018) of acute leukemia patients was significantly increased comparing with those of healthy volunteers (0.5142±0.1340) (t= 2.634, P ＜0.05).After treatment with TSA for 48 hours, the protein expression of hMSH2 was increased nearly 1.5-fold, hMLH1 about 1.6-fold, H3 about 2.9-fold and H4 about 3.4-fold comparing with the negative control groups (P ＜0.05),while the protein expression of HDAC1 were decreased comparing with the negative control groups by 40 %.Conclusion There was an low expression phenomenon of histone acetylation in acute leukemia, and histone acetylation played an important role in regulation of the mismatch repair gene expression in acute leukemia.

Humans ; Severe Acute Respiratory Syndrome ; diagnosis ; therapy