Structure of a TOC-TIC supercomplex spanning two chloroplast envelope membranes.

The TOC and TIC complexes are essential translocons that facilitate the import of the nuclear genome-encoded preproteins across the two envelope membranes of chloroplast, but their exact molecular identities and assembly remain unclear. Here, we report a cryoelectron microscopy structure of TOC-TIC supercomplex from Chlamydomonas, containing a total of 14 identified components. The preprotein-conducting pore of TOC is a hybrid ß-barrel co-assembled by Toc120 and Toc75, while the potential translocation path of TIC is formed by transmembrane helices from Tic20 and YlmG, rather than a classic model of Tic110. A rigid intermembrane space (IMS) scaffold bridges two chloroplast membranes, and a large hydrophilic cleft on the IMS scaffold connects TOC and TIC, forming a pathway for preprotein translocation. Our study provides structural insights into the TOC-TIC supercomplex composition, assembly, and preprotein translocation mechanism, and lays a foundation to interpret the evolutionary conservation and diversity of this fundamental translocon machinery.

Utilizing codon degeneracy in the design of donor DNA for CRISPR/Cas9-mediated gene editing to streamline the screening process for single amino acid mutations.

Chlamydomonas reinhardtii, a unicellular green alga, has been widely used as a model organism for studies of algal, plant and ciliary biology. The generation of targeted amino acid mutations is often necessary, and this can be achieved using CRISPR/Cas9 induced homology-directed repair to install genomic modifications from exogenous donor DNA. Due to the low gene editing efficiency, the technical challenge lies in identifying the mutant cells. Direct sequencing is not practical, and pre-screening is required. Here, we report a strategy for generating and screening for amino acid point mutations using the CRISPR/Cas9 gene editing system. The strategy is based on designing donor DNA using codon degeneracy, which enables the design of specific primers to facilitate mutant screening by PCR. An in vitro assembled RNP complex, along with a dsDNA donor and an antibiotic resistance marker, was electroporated into wild-type cells, followed by PCR screening. To demonstrate this principle, we have generated the E102K mutation in centrin and the K40R mutation in α-tubulin. The editing efficiencies at the target sites for Centrin, TUA1, TUA2 were 4, 24 and 8% respectively, based on PCR screening. More than 80% of the mutants with the expected size of PCR products were precisely edited, as revealed by DNA sequencing. Subsequently, the precision-edited mutants were biochemically verified. The introduction of codon degeneracy did not affect the gene expression of centrin and α-tubulins. Thus, this approach can be used to facilitate the identification of point mutations, especially in genes with low editing rates.

FBB18 participates in preassembly of almost all axonemal dyneins independent of R2TP complex.

Assembly of dynein arms requires cytoplasmic processes which are mediated by dynein preassembly factors (DNAAFs). CFAP298, which is conserved in organisms with motile cilia, is required for assembly of dynein arms but with obscure mechanisms. Here, we show that FBB18, a Chlamydomonas homologue of CFAP298, localizes to the cytoplasm and functions in folding/stabilization of almost all axonemal dyneins at the early steps of dynein preassembly. Mutation of FBB18 causes no or short cilia accompanied with partial loss of both outer and inner dynein arms. Comparative proteomics using 15N labeling suggests partial degradation of almost all axonemal dynein heavy chains (DHCs). A mutant mimicking a patient variant induces particular loss of DHCα. FBB18 associates with 9 DNAAFs and 14 out of 15 dynein HCs but not with IC1/IC2. FBB18 interacts with RuvBL1/2, components of the HSP90 co-chaperone R2TP complex but not the holo-R2TP complex. Further analysis suggests simultaneous formation of multiple DNAAF complexes involves dynein folding/stability and thus provides new insights into axonemal dynein preassembly.

Polyvinyl Chloride Microplastics Facilitate Nitrous Oxide Production in Partial Nitritation Systems.

Partial nitritation (PN) is an important partner with anammox in the sidestream line treating high-strength wastewater and primarily contributes to nitrous oxide (N2O) emissions in such a hybrid system, which also suffers from ubiquitous microplastics because of the growing usage and disposal levels of plastics. In this study, the influences of polyvinyl chloride microplastics (PVC-MPs) on N2O-contributing pathways were experimentally revealed to fill the knowledge gap on N2O emission from the PN system under microplastics stress. The long-term results showed that the overall PN performance was hardly affected by the low-dose PVC-MPs (0.5 mg/L) while obviously deteriorated by the high dose (5 mg/L). According to the batch tests, PVC-MPs reduced biomass-specific ammonia oxidation rates (AORs) by 5.78-21.94% and stimulated aerobic N2O production by 9.22-88.36%. Further, upon increasing dissolved oxygen concentrations from 0.3 to 0.9 mg O2/L, the degree of AOR inhibition increased but that of N2O stimulation was lightened. Site preference analysis in combination with metabolic inhibitors demonstrated that the contributions of hydroxylamine oxidation and heterotrophic denitrification to N2O production at 0.3 mg O2/L were enhanced by 18.84 and 10.34%, respectively, accompanied by a corresponding decreased contribution of nitrifier denitrification. Finally, the underlying mechanisms proposed for negative influences of PVC-MPs were bisphenol A leaching and reactive oxygen species production, which led to more cell death, altered sludge properties, and reshaped microbial communities, further resulting in enhanced N2O emission. Overall, this work implied that the ubiquitous microplastics are a hidden danger that cannot be ignored in the PN system.

High-resolution mass spectrometry-based non-targeted metabolomics reveals toxicity of naphthalene on tall fescue and intrinsic molecular mechanisms.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous at relatively high concentrations by atmospheric deposition, and they are threatening to the environment. In this study, the toxicity of naphthalene on tall fescue and its potential responding mechanism was first studied by integrating approaches. Tall fescue seedlings were exposed to 0, 20, and 100 mg L-1 naphthalene in a hydroponic environment for 9 days, and toxic effects were observed by the studies of general physiological studies, chlorophyll fluorescence, and root morphology. Additionally, Ultra Performance Liquid Chromatography - Electrospray Ionization - High-Resolution Mass Spectrometry (UPLC-ESI-HRMS) was used to depict metabolic profiles of tall fescue under different exposure durations of naphthalene, and the intrinsic molecular mechanism of tall fescue resistance to abiotic stresses. Tall fescue shoots were more sensitive to the toxicity of naphthalene than roots. Low-level exposure to naphthalene inhibited the electron transport from the oxygen-evolving complex (OEC) to D1 protein in tall fescue shoots but induced the growth of roots. Naphthalene induced metabolic change of tall fescue roots in 12 h, and tall fescue roots maintained the level of sphingolipids after long-term exposure to naphthalene, which may play important roles in plant resistance to abiotic stresses.

Efficacy analysis of minimally invasive surgery for Raynaud's syndrome.

BACKGROUND: Raynaud's syndrome (RS), also referred to as Raynaud's phenomenon, is a vasospastic disorder causing episodic color changes in extremities upon exposure to cold or stress. These manifestations, either primary Raynaud's phenomenon (PRP) or associated with connective tissue diseases like systemic sclerosis (SSc) as secondary Raynaud's phenomenon (SRP), affect the quality of life. Current treatments range from calcium channel blockers to innovative surgical interventions, with evolving efficacy and safety profiles. METHODS: In this retrospective study, patients diagnosed with RS were selected based on complete medical records, ensuring homogeneity between groups. Surgeries involved microscopic excision of sympathetic nerve fibers and stripping of the digital artery's adventitia. Postoperative care included antibiotics, analgesia, oral nifedipine, and heat therapies. Evaluation metrics such as the VAS pain score and RCS score were collected bi-weekly. Data analysis was conducted using SPSS 26.0, with significance set at p < 0.05. RESULTS: In total, 15 patients formed the experimental group, with five presenting fingertip soft tissue necrosis and ten showing RS symptoms. Comparative analysis of demographic data between experimental and control groups, both containing 15 participants, demonstrated no significant age and gender difference. However, the "Mean Duration of RP attack" in the experimental group was notably shorter (9.47 min ± 0.31) than the control group (19.33 min ± 1.79). The RS Severity Score also indicated milder severity for the experimental cohort (score: 8.55) compared to the control (score: 11.23). Postoperative assessments at 2, 4, and 6 weeks revealed improved VAS pain scores, RCS scores, and other measures for the experimental group, showing significant differences (p < 0.05). One distinctive case showcased a variation in the common digital nerve and artery course in an RS patient. CONCLUSION: Our retrospective analysis on RS patients indicates that microsurgical techniques are safe and effective in the short term. As surgical practices lean towards minimally invasive methods, our data supports this shift. However, extensive, prospective studies are essential for conclusive insights.

SNHG8 promotes cell proliferation, migration, and invasion of nasopharyngeal carcinoma cells as an oncogene through miR-588/HMGA2 axis.

Nasopharyngeal carcinoma (NC) poses a threat to the life of patients. Long non-coding RNA (LncRNA) is a novel kind of non-coding RNA, which plays a pivotal role through sponge microRNA (miRNA). Abnormal expression of small nucleolar RNA host gene 8 (SNHG8) is involved in various tumors; however, the role of SNHG8 in NC remains unknown. Quantitative real-time PCR (qRT-PCR) and Western blotting was employed to detect the expression levels of SNHG8, miR-588, and high mobility group A2 (HMGA2). Cell proliferation, migration, and invasion were analyzed by CCK-8 and transwell assays. miR-588 binding sites in SNHG8 were predicted by LncBase analysis. Luciferase reporter and RNA pull-down assay were used to confirm the interaction of SNHG8 and miR-588. SNHG8 was highly expressed in NC cells. The prognosis of the patients with NC in the high expression levels of SNHG8 was poorer than that in the low expression levels. The expression of SNHG8 was closely related to tumor size, TNM stage, and distal metastasis. Knockdown of SNHG8 inhibited cell proliferation, migration, and invasion of NC. SNHG8 targeted miR-588. Inhibition of miR-588 could partially reverse the knockdown of SNHG8 in NC cells, and miR-588 targeted HMGA2. In conclusion, SNHG8 promotes proliferation, migration, and invasion of NC cells through miR-588/HMGA2 in NC as an oncogene.

Line-scan Raman scattering image and multivariate analysis for rapid and noninvasive detection of restructured beef.

The mean spectral (MS) features were extracted from Raman scattering images (RSI) of beef samples over the region of interest covering the spectral range of 789-1710cm-1 and the spatial offset range of 0-5 mm (for two sides of the incident laser). The RSI monitored the main change in the protein, amide bands, lipids, and amino acid residues. The classification model performance based on MS features compared the conventional Raman spectral features and confirmed the usefulness of RSI. Finally, the results showed that RSI technology is a reliable tool for rapid and noninvasive detection of restructured beef.

School-based factors influencing physical activity participation in children and adolescents with disabilities: A qualitative systematic review and meta-synthesis.

BACKGROUND: Children and adolescents with disabilities (CAD) frequently encounter barriers to participation in physical activity (PA). Schools play a vital role in promoting PA, making it crucial to understand the school-based factors influencing CAD's PA participation. OBJECTIVE: This qualitative systematic review and meta-synthesis aims to identify and elucidate the school-based factors influencing PA engagement among this population. METHODS: A comprehensive search across six databases-Web of Science, PsycINFO, Scopus, SPORTDiscus, and Embase, CNKI-was conducted in August 2023, and subsequently updated in April 2024. English or Chinese peer-reviewed journal articles that contained substantial qualitative data regarding school-based factors affecting PA in CAD were included. The methodological quality of included studies was evaluated utilizing the Critical Appraisal Skills Program Qualitative Checklist. Qualitative data were analyzed through thematic synthesis. RESULTS: A total of 16 studies (12 qualitative studies and 4 mixed-methods studies) were included, all of which were of moderate to high quality. Thematic synthesis identified four major themes: (a) physical environment (provision of facilities, specialized and adapted equipment, space for activities); (b) social environment (peers, school leaders, teachers and other school staff); (c) opportunities for PA (physical education, classroom movement integration, extra-curricular activities); and (d) characteristics of PA (adaption of rules and task difficulty, competition components, diversified activities, fun). CONCLUSIONS: This review reveals the complex interplay of different school-based factors affecting PA participation among CAD. The findings provide valuable insights for educators, policymakers, and health professionals to enhance PA participation in this population.

Prevalence of meeting 24-hour movement guidelines and its associations with health indicators in people with disabilities: A systematic review and meta-analysis.

BACKGROUND: Meeting the 24-h movement guidelines (i.e., physical activity, sedentary behavior, sleep) could generate health benefits to people with disabilities. However, no systematic reviews or meta-analyses have examined the prevalence of meeting these guidelines and associations with health indicators in this group. OBJECTIVE: This systematic review and meta-analysis aimed to examine the prevalence of meeting the 24-h movement guidelines and associations with health indicators among people with disabilities. METHODS: Six electronic databases were searched for studies published in English from inception to May 31, 2023. Meta-analyses with the random-effects model were used to determine the prevalence of meeting the 24-h movement guidelines. Qualitative syntheses were employed to describe the associations between meeting the guidelines and health indicators. RESULTS: Twenty-four studies comprising 77510 participants (41.6% females) with disabilities aged 6-65 years from eight countries were identified. Overall, 6.97% of the participants with disabilities met all 24-h movement guidelines, and 16.65% met none of the guidelines. Significant age (P = 0.006) and disability type (P = 0.001) differences were found in meeting all guidelines. Participants with disabilities who met all guidelines reported better psychosocial health indicators (9/9 studies) than those met none or only one of the guidelines. There was limited evidence or research for other health indicators. CONCLUSION: There is some evidence showing that the prevalence of meeting all 24-h movement guidelines in people with disabilities is low. Meanwhile, there is preliminary evidence suggesting that meeting all guidelines is associated with better psychosocial health than meeting none of the guidelines.

Construction of active-inert core-shell structured nanocrystals for broad range multicolor upconversion luminescence.

Rare earth doped up-conversion luminescent nano-materials exhibit abundant emission colors under suitable excitation condition. In this work, NaYF4:Er/Ho@NaYF4 and NaYbF4:Tm@NaYF4 nanoparticles were synthesized by co-precipitation method. The pure red emission can be realized by the designed NaYF4:Er/Ho@NaYF4 nanocrystals and the R/Gs reach 23.3 and 25 under excitations of 980 and 1550 nm lasers, respectively. The R/G declines as the power increasing with the emission color changing from red to yellow, which is due to the quick saturation of the energy levels, radiating red emissions. Meanwhile, the emission intensity of NaYbF4:Tm@NaYF4 nanocrystals increases by 58.3 folds after encasing the inert shell NaYF4 and the CIE color coordinate reaches (0.1646, 0.0602) under 980 nm laser excitation. Furthermore, broad range multicolor from blue to red and yellow up-conversion emissions is achieved by mixing NaYF4:Er/Ho@NaYF4 and NaYbF4:Tm@NaYF4 nanocrystals, which could be applied to colorful displaying, security anti-counterfeiting and information coding.

Peracetic acid (PAA)-based pretreatment effectively improves medium-chain fatty acids (MCFAs) production from sewage sludge.

Peracetic acid (PAA), known for its environmentally friendly properties as a oxidant and bactericide, is gaining prominence in decontamination and disinfection applications. The primary product of PAA oxidation is acetate that can serve as an electron acceptor (EA) for the biosynthesis of medium-chain fatty acids (MCFAs) via chain elongation (CE) reactions. Hence, PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation, as it could enhance organic matter availability, suppress competing microorganisms and furnish EA by providing acetate. However, such a hypothesis has rarely been proved. Here we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances (EPS) from sludge flocs and disruption of proteinic secondary structures, through inducing highly active free radicals and singlet oxygen. The production of MCFAs increases substantially to 11,265.6 mg COD L-1, while the undesired byproducts, specifically long-chain alcohols (LCAs), decrease to 723.5 mg COD L-1. Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process, attributed to the up-regulation of functional genes involved in fatty acid biosynthesis pathway. These comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology, advancing our understanding of sustainable resource recovery from sewage sludge.

Potential coupling of microbial methane, nitrogen, and sulphur cycling in the Okinawa Trough cold seep sediments.

The Okinawa Trough (OT) is a back-arc basin with a wide distribution of active cold seep systems. However, our understanding of the metabolic function of microbial communities in the cold seep sediments of the OT remains limited. In this study, we investigated the vertical profiles of functional genes involved in methane, nitrogen, and sulphur cycling in the cold seep sediments of the OT. Furthermore, we explored the possible coupling mechanisms between these biogeochemical cycles. The study revealed that the majority of genes associated with the nitrogen and sulphur cycles were most abundant in the surface sediment layers. However, only the key genes responsible for sulphur disproportionation (sor), nitrogen fixation (nifDKH), and methane metabolism (mcrABG) were more prevalent within sulfate-methane transition zone (SMTZ). Significant positive correlations (P < 0.05) were observed between functional genes involved in sulphur oxidation, thiosulphate disproportionation with denitrification, and dissimilatory nitrate reduction to ammonium (DNRA), as well as between AOM/methanogenesis and nitrogen fixation, and between sulphur disproportionation and AOM. A genome of Filomicrobium (class Alphaproteobacteria) has demonstrated potential in chemoautotrophic activities, particularly in coupling DNRA and denitrification with sulphur oxidation. Additionally, the characterized sulfate reducers such as Syntrophobacterales have been found to be capable of utilizing nitrate as an electron acceptor. The predominant methanogenic/methanotrophic groups in the OT sediments were identified as H2-dependent methylotrophic methanogens (Methanomassiliicoccales and Methanofastidiosales) and ANME-1a. This study offered a thorough understanding of microbial ecosystems in the OT cold seep sediments, emphasizing their contribution to nutrient cycling.IMPORTANCEThe Okinawa Trough (OT) is a back-arc basin formed by extension within the continental lithosphere behind the Ryukyu Trench arc system. Cold seeps are widespread in the OT. While some studies have explored microbial communities in OT cold seep sediments, their metabolic potential remains largely unknown. In this study, we used metagenomic analysis to enhance comprehension of the microbial community's role in nutrient cycling and proposed hypotheses on the coupling process and mechanisms involved in biogeochemical cycles. It was revealed that multiple metabolic pathways can be performed by a single organism or microbes that interact with each other to carry out various biogeochemical cycling. This data set provided a genomic road map on microbial nutrient cycling in OT sediment microbial communities.

MINet: Multi-scale input network for fundus microvascular segmentation.

Vessel segmentation in fundus images is a key procedure in the diagnosis of ophthalmic diseases, which can play a role in assisting doctors in diagnosis. Although current deep learning-based methods can achieve high accuracy in segmenting fundus vessel images, the results are not satisfactory in segmenting microscopic vessels that are close to the background region. The reason for this problem is that thin blood vessels contain very little information, with the convolution operation of each layer in the deep network, this part of the information will be randomly lost. To improve the segmentation ability of the small blood vessel region, a multi-input network (MINet) was proposed to segment vascular regions more accurately. We designed a multi-input fusion module (MIF) in the encoder, which is proposed to acquire multi-scale features in the encoder stage while preserving the microvessel feature information. In addition, to further aggregate multi-scale information from adjacent regions, a multi-scale atrous spatial pyramid (MASP) module is proposed. This module can enhance the extraction of vascular information without reducing the resolution loss. In order to better recover segmentation results with details, we designed a refinement module, which acts on the last layer of the network output to refine the results of the last layer of the network to get more accurate segmentation results. We use the HRF, CHASE_DB1 public dataset to validate the fundus vessel segmentation performance of the MINet model. Also, we merged these two public datasets with our collected Ultra-widefield fundus image (UWF) data as one dataset to test the generalization ability of the model. Experimental results show that MINet achieves an F1 score of 0.8324 on the microvessel segmentation task, achieving a high accuracy compared to the current mainstream models.

Celastrol attenuates HFD-induced obesity and improves metabolic function independent of adiponectin signaling.

Backgound: Celastrol, a leptin sensitiser, has been shown to inhibit food intake and reduce body weight in diet-induced obese mice, making it a potential treatment for obesity and metabolic diseases. Adiponectin signalling has been reported to play an important role in the treatment of obesity, inflammation, and non-alcoholic fatty liver disease.Materials and methods: Wild-type (WT) and AdipoR1 knockout (AdipoR1-/-) mice were placed on a chow diet or a high-fat diet (HFD) and several metabolic parameters were measured. Celastrol was then administered to the HFD-induced mice and the response of WT and AdipoR1-/- mice to celastrol in terms of body weight, blood glucose, and food intake was also recorded.Results: AdipoR1 knockout caused elevated blood glucose and lipids, impaired glucose tolerance and insulin resistance in mice, as well as increased susceptibility to HFD-induced obesity. After 14 days of treatment, WT and AdipoR1-/- mice showed significant reductions in body weight and blood glucose and improvements in glucose tolerance.Conclusion: The present study demonstrated that AdipoR1 plays a critical role in metabolic regulation and that the improvement of weight and metabolic function by celastrol is independent of the AdipoR1-mediated signalling pathway.

Unveiling the roles of biofilm in reducing N2O emission in a nitrifying integrated fixed-film activated sludge (IFAS) system.

Biofilm process such as integrated fixed-film activated sludge (IFAS) system has been preliminarily found to produce less nitrous oxide (N2O) than suspended sludge system. However, the N2O emission behaviors and underlying N2O mitigation mechanism in such hybrid system remain unclear. This study therefore aims to fully unveil the roles of biofilm in reducing N2O emission in a nitrifying IFAS system with the aid of some advanced technologies such as N2O microsensor and site-preference analysis. It was found that ammonia oxidation occurred mostly in the sludge flocs (˃ 86%) and biofilm could reduce N2O emission by 43.77% in a typical operating cycle. Biofilm not only reduced nitrite accumulation in nitrification process, inhibiting N2O production via nitrifier denitrification pathway, but also served as a N2O sink, promoting the reduction of N2O via endogenous denitrification. As a result, N2O emissions from the IFAS system were 50%-83% lower than those from the solo sludge flocs. Further, more N2O emission was reduced in the presence of biofilm with decreasing the dissolved oxygen level in the range of 0.5-3.0 mg O2/L. Microbial community and key enzyme analyses revealed that biofilm had relatively high microbial diversity and unique enzyme composition, providing a reasonable explanation for the changed contributions of different N2O production pathways and reduced N2O emission.

Effects of Virtual Reality-Based Exercise on Physical Fitness in People with Intellectual Disability: A Systematic Review of Randomized Controlled Trials.

It is unclear whether virtual reality (VR)-based exercise can improve physical fitness in people with intellectual disability (ID). This systematic review therefore aimed to synthesize existing evidence regarding the efficacy of VR-based exercise on physical fitness in people with ID. Eligible articles were searched through six major electronic databases from inception until August 15, 2022. Returned studies were screened through predefined inclusion and exclusion criteria. Data from the included studies were then extracted and synthesized. A total of 13 randomized controlled trials were included and 12 of them were found to have good research quality. Different physical fitness outcomes were evaluated: (1) muscular fitness (d = 0.05-2.12; proportion of effect = 5/6), (2) cardiorespiratory fitness (d = 0.12-0.67; proportion of effect = 5/5), (3) flexibility (d = 0.81; proportion of effect = 1/2), (4) body composition (d = 0.10; proportion of effect = 2/3), (5) balance (d = 0.23-1.65; proportion of effect = 6/7), (6) coordination (d = 0.19-0.48; proportion of effect = 2/3), (7) speed and agility (d = 0.13-0.46; proportion of effect = 4/4), and (8) overall motor proficiency (d = 0.02-1.08; proportion of effect = 1/3). While there was some preliminary evidence showing that VR-based exercise could improve muscular fitness, cardiorespiratory fitness, balance, and speed and agility in individuals with ID, other outcomes showed less conclusive or limited positive evidence. Overall, additional studies are needed to understand the benefits of VR-based exercise on physical fitness in people with ID.

Research Progress of Novel Drug Delivery Systems of Chinese Medicine Monomers based on Natural Silk Fibroin: A Mini-Review.

Traditional Chinese medicine (TCM) has a good curative effect, but its disadvantages include complex components, poor drug stability, potential drug interaction, etc. Therefore, it is particularly important to construct a novel drug delivery system that can load Chinese medicine monomers to solve this problem. Silk fibroin is a kind of natural polymer material with unique properties. It can be used as a carrier material to load Chinese medicine monomers to prepare novel drug delivery systems that significantly affect treating diseases without toxic and side effects. However, there is still a lack of a review on silk fibroin as a carrier material to load Chinese medicine monomers to explore and analyze the current research results and progress. Here, our article focuses on the in-depth excavation and analysis of the recent research on novel drug delivery systems prepared by silk fibroin and TCM monomers. Besides, the characteristics, existing problems, and prospects of silk fibroin are discussed and explained. It is hoped that this research can provide a reference and basis for the modernization of TCM, the design of novel drug delivery systems, the research and development of new drugs in the future, and contribute to the innovation of silk protein.

A new NASH model in aged mice with rapid progression of steatohepatitis and fibrosis.

Non-alcoholic fatty liver disease (NAFLD) has a high prevalence worldwide, with a significant proportion of patients progressing into non-alcoholic steatohepatitis (NASH) and further into cirrhosis and hepatocellular carcinoma (HCC). Most of the current animal models of NASH have limitations, such as incompatibility with human pathogenesis characteristics or long induction periods, which severely limit the development of new drugs and preclinical studies for NASH. We investigated the progression of NASH and fibrosis, as well as metabolic indicators, at different time points in aged mice induced by the Gubra Amylin NASH (GAN) diet, a high-fat, high-sugar, high-cholesterol diet, and attempted to establish a rapid and useful mouse model of NASH. Young and aged C57BL/6 mice were induced on a normal chow or GAN diet for 12 and 21 weeks, respectively. After 12 weeks of induction, aged mice developed NASH, including hepatic steatosis, lobular inflammation and hepatic ballooning, and the phenotype was more severe compared with young mice. After 21 weeks of induction, aged mice developed hepatic fibrosis, which greatly shortened the induction time compared with young mice. Furthermore, analysis of immune cell infiltration in the liver by flow cytometry elucidated the changes of multiple immune cells during the pathogenesis of NASH. These findings suggest that aged mice may develop NASH and fibrosis more rapidly under GAN diet induction, which may significantly shorten the period for preclinical studies of NASH.