Bioinspired Framework Catalysts: From Enzyme Immobilization to Biomimetic Catalysis.

Enzymatic catalysis has fueled considerable interest from chemists due to its high efficiency and selectivity. However, the structural complexity and vulnerability hamper the application potentials of enzymes. Driven by the practical demand for chemical conversion, there is a long-sought quest for bioinspired catalysts reproducing and even surpassing the functions of natural enzymes. As nanoporous materials with high surface areas and crystallinity, metal-organic frameworks (MOFs) represent an exquisite case of how natural enzymes and their active sites are integrated into porous solids, affording bioinspired heterogeneous catalysts with superior stability and customizable structures. In this review, we comprehensively summarize the advances of bioinspired MOFs for catalysis, discuss the design principle of various MOF-based catalysts, such as MOF-enzyme composites and MOFs embedded with active sites, and explore the utility of these catalysts in different reactions. The advantages of MOFs as enzyme mimetics are also highlighted, including confinement, templating effects, and functionality, in comparison with homogeneous supramolecular catalysts. A perspective is provided to discuss potential solutions addressing current challenges in MOF catalysis.

Carvacrol ameliorates skin allograft rejection through modulating macrophage polarization by activating the Wnt signalling pathway.

Post-transplantation immune rejection remains an important factor for transplant patients. However, conventional immunosuppressants are associated with substantial adverse effects. Natural immunosuppressants present a promising alternative to conventional counterparts, boasting exceptional biological activity, minimal toxicity and reduced side effects. We identified carvacrol as a prospective immunosuppressive agent following T cell proliferation experiment and validated carvacrol's immunosuppressive efficacy in the murine allogeneic skin graft model. T cell proliferation assay was used to screen natural small molecule compounds and the immunosuppressive effect of compounds was evaluated in MHC-mismatched murine allogeneic skin graft model. H&E and immunohistochemical staining were applied to evaluate the pathological grade. Furthermore, flow cytometry was uitlized to analyse the immunophenotype changes of immune cells. Western blotting and q-PCR were used to detect the expression of key molecules in macrophages. In vitro, carvacrol demonstrates significant inhibition of the proliferation of CD4+ T and CD8+ T cells. It notably reduces inflammatory factor expression within the allografts, suppresses T cell differentiation toward Th1 phenotype and expansion. Furthermore, carvacrol prominently hinders M1-type macrophages polarization by activating Wnt signaling. Notably, the anti-rejection efficacy of carvacrol was significantly weakened upon the removal of macrophages in mice using chlorophosphate liposomes. Carvacrol could significantly inhibit T cell proliferation, alleviate graft rejection and has outstanding toxicological safety. The molecular mechanism of the anti-rejection effect of carvacrol is closely related to its mediating activation of macrophage Wnt pathway, inhibiting M1 polarization and inducing T cell differentiation.

Liver transplantation for Hepatocellular Carcinoma: A prognostic model incorporating pretransplant inflammatory cytokines.

PURPOSE: Liver transplantation (LT) remains an optimal treatment for selected hepatocellular carcinoma (HCC). Cytokines can be obtained by minimally invasive techniques and are associated with the development of HCC. The purpose of our investigation was to explore the prognostic value of pretransplant serum inflammatory cytokine profiles in HCC patients for LT. METHODS: We detected forty inflammatory cytokines in pre-LT serum from 42 HCC patients by using an inflammation-related antibody array. A pretransplant serum inflammatory cytokine-associated risk assessment model (pre-SCRAM) was developed and was validated in an external cohort of 213 HCC patients who underwent LT and were then followed prospectively. RESULTS: The pre-LT factors independently associated with recurrence-free survival (RFS) were as follows: B-lymphocyte chemoattractant (BLC), interleukin (IL)-12p40 and maximum tumor diameter. High IL-12P40 level was associated with a significantly smaller maximum tumor diameter (p = 0.021), decreased proportion of nodules ≥ 3 (p = 0.001), lower platelet counts (p = 0.011) and lower portal vein tumor thrombus (p = 0.031). Conversely, recipients with poor BLC level had higher alpha-fetoprotein (AFP) levels (p = 0.016). Kaplan-Meier analyses revealed that high pre-LT BLC or IL-12p40 level was associated with superior RFS. The pre-SCRAM stratified recipients into three risk groups: high risk, intermediate risk and low risk. In the validation cohort, for patients in the high, intermediate, and low risk groups, the 3-year RFS rates were 29.3%, 58.7%, and 82.2%, respectively, the 3-year HCC-specific survival rates were 54.5%, 73.8%, and 86%, respectively, and the 3-year overall survival rates were 44.4%, 60.9%, and 79.9%, respectively. The pre-SCRAM model performed well and remained significant in optimizing the risk stratification of recurrence in patients beyond the Milan criteria or the AFP model. CONCLUSION: Pretransplant cytokine profiles can provide powerful prognostic information in the setting of LT for HCC. A pre-LT risk model incorporating cytokines showed excellent efficiency in recurrence prediction for HCC patients, which could ultimately stratify the prognosis in patients beyond the Milan criteria or the AFP model.

Methylation site APC112043544 as a potential biomarker for post-transplant hepatocellular carcinoma recurrence.

Objective: To investigate the prognostic value of DNA methylation of tumor suppressor genes for hepatocellular carcinoma (HCC) recurrence after liver transplantation. Methods: APC gene was selected according to The Cancer Genome Atlas dataset. Tumor tissues and clinical data of 85 HCC patients who received a liver transplantation were retrospectively enrolled and next-generation methylation sequencing was performed. Risk factors were determined using the Cox proportional-hazard-regression model. Results: The APC methylation site (chromosome 5, position 112043544) was an independent predictor of post-transplant HCC recurrence. Patients with hyper-methylated APC112043544 experienced superior recurrence-free survival (p = 0.021) and had a decreased proportion of microvascular invasion (p = 0.017). APC112043544 also predicted recurrence risk in patients beyond selection criteria. Conclusions: APC112043544 methylation may serve as a potential biomarker for post-transplant HCC recurrence.

Nanoparticle formulation of mycophenolate mofetil achieves enhanced efficacy against hepatocellular carcinoma by targeting tumour-associated fibroblast.

Hepatocellular carcinoma (HCC) is one of the most aggressive tumours with marked fibrosis. Mycophenolate mofetil (MMF) was well-established to have antitumour and anti-fibrotic properties. To overcome the poor bioavailability of MMF, this study constructed two MMF nanosystems, MMF-LA@DSPE-PEG and MMF-LA@PEG-PLA, by covalently conjugating linoleic acid (LA) to MMF and then loading the conjugate into polymer materials, PEG5k -PLA8k and DSPE- PEG2k , respectively. Hepatocellular carcinoma cell lines and C57BL/6 xenograft model were used to examine the anti-HCC efficacy of nanoparticles (NPs), whereas NIH-3T3 fibroblasts and highly-fibrotic HCC models were used to explore the anti-fibrotic efficacy. Administration of NPs dramatically inhibited the proliferation of HCC cells and fibroblasts in vitro. Animal experiments revealed that MMF-LA@DSPE-PEG achieved significantly higher anti-HCC efficacy than free MMF and MMF-LA@PEG-PLA both in C57BL/6 HCC model and highly-fibrotic HCC models. Immunohistochemistry further confirmed that MMF-LA@DSPE-PEG dramatically reduced cancer-associated fibroblast (CAF) density in tumours, as the expression levels of alpha-smooth muscle actin (α-SMA), fibroblast activation protein (FAP) and collagen IV were significantly downregulated. In addition, we found the presence of CAF strongly correlated with increased HCC recurrence risk after liver transplantation. MMF-LA@DSPE-PEG might act as a rational therapeutic strategy in treating HCC and preventing post-transplant HCC recurrence.

Targeting peripheral immune organs with self-assembling prodrug nanoparticles ameliorates allogeneic heart transplant rejection.

Organ transplantation has become a mainstay of therapy for patients with end-stage organ diseases. However, long-term administration of immunosuppressive agents, a scheme for improving the survival of transplant recipients, has been compromised by severe side effects and posttransplant complications. Therapeutic delivery targeting immune organs has the potential to address these unmet medical issues. Here, through screening of a small panel of mammalian target of rapamycin complex kinase inhibitor (TORKinib) compounds, a TORKinib PP242 is identified to be able to inhibit T cell function. Further chemical derivatization of PP242 using polyunsaturated fatty acids (i.e., docosahexaenoic acid) transforms this water-insoluble hydrophobic agent into a self-assembling nanoparticle (DHA-PP242 nanoparticle [DPNP]). Surface PEGylation of DPNP with amphiphilic copolymers renders the nanoparticles aqueously soluble for preclinical studies. Systemically administered DPNP shows tropism for macrophages within peripheral immune organs. Furthermore, DPNP regulates differentiation of adoptively transferred T cells in a macrophage-dependent manner in Rag1-/- mouse model. In an experimental model of heart transplantation, DPNP significantly extends the survival of grafts through inducing immune suppression, thus reducing the inflammatory response of the recipients. These findings suggest that targeted delivery of TORKinibs exploiting prodrug-assembled nanoparticle scaffolds may provide a therapeutic option against organ rejection.

DNA methylation of SOCS1/2/3 predicts hepatocellular carcinoma recurrence after liver transplantation.

DNA methylation status of SOCS1/SOCS2/SOCS3 is intensely involved in the development and progression of hepatocellular carcinoma (HCC). This study explored its prognostic value for HCC recurrence after liver transplantation (LT). Clinical data from 62 HCC patients who underwent LT at our centre were retrospectively collected. The SOCS1/2/3 methylation level were determined using next generation sequencing. Overall, 244 methylated sites at the SOCS1/2/3 promoter were identified. Multivariate analysis yielded the methylated sites SOCS2-1-90 (Chromosome 12, Position 93963982; HR 0.386, 95% CI 0.149-0.998) and SOCS1-1-68 (Chromosome 16, Position 11350699; HR 4.376, 95% CI 1.324-14.459) as independent predictors of post-LT HCC recurrence. Patients were divided into highly- and lowly methylated groups according to the median SOCS1-1-68 (0.95%) and SOCS2-1-90 (1.05%) methylation levels. Highly methylated SOCS2-1-90 was associated with significantly lower AFP levels (P = 0.008), decreased proportion of maximal tumour size > 8 cm (P = 0.02), and better pathological grading (P = 0.06). Conversely, patients in the highly methylated SOCS1-1-68 group had higher AFP levels (P = 0.043). Kaplan-Meier analyses revealed that patients with highly methylated SOCS2-1-90 had increased recurrence free survival (RFS) and overall survival (OS) rates when compared with those with lowly methylated SOCS2-1-90 (P = 0.0041 and 0.012, respectively). Nevertheless, the correlation between methylated SOCS1-1-68 and cumulative recurrence rates was less pronounced (P = 0.098). Subgroup analyses demonstrated that patients meeting the Milan criteria, UCSF criteria, Metroticket 2.0 Model or Hangzhou criteria with highly methylated SOCS2-1-90 had the best RFS rates. DNA methylation of SOCS2-1-90 is a novel biomarker for predicting post-transplant HCC recurrence.

Influence of orthodontic treatment with premolar extraction on the spatial position of maxillary third molars in adult patients: a retrospective cohort cone-bean computed tomography study.

BACKGROUND: Based on low-dose radiation Cone-bean computed tomography (CBCT) images, This study aims to establish a space coordinate system, which offers more precise and comparable evaluation on changes of maxillary third molars influenced by orthodontic treatment with premolar extraction in adults. The system suggests promising application prospect in future studies related to CBCT superimposition and evaluation for its feasibility and efficiency. METHODS: Forty-nine maxillary third molars from 27 patients (mean age, 20.78 years) were included. CBCT images were obtained before and after orthodontic treatment with premolars extracted (mean treatment duration, 31.47 months). The changes in the position, angulation, and rotation of the third molars were evaluated with a space coordinate system using four landmarks: anterior nasal spine (ANS), posterior nasal spine (PNS), left and right orbitales. RESULTS: After orthodontic treatment, the third molars moved forward (adjusted mean, 1.44 mm) (p < 0.001) and downward (adjusted mean, 2.87 mm) (p < 0.001) accompanied by outward rotation of the crowns (adjusted mean, 5.38°) (p = 0.001), while changes in angulation were insignificant. CONCLUSIONS: This was the first study to systematically investigate the spatial position change of maxillary third molars in adult patients who received orthodontic treatment with premolar extraction. During the process, maxillary third molars moved downward and forward accompanied by outward rotation of the crowns. Orthodontists should take tooth movement potential into consideration when making extraction plans.

The sequence and de novo assembly of the giant panda genome.

Using next-generation sequencing technology alone, we have successfully generated and assembled a draft sequence of the giant panda genome. The assembled contigs (2.25 gigabases (Gb)) cover approximately 94% of the whole genome, and the remaining gaps (0.05 Gb) seem to contain carnivore-specific repeats and tandem repeats. Comparisons with the dog and human showed that the panda genome has a lower divergence rate. The assessment of panda genes potentially underlying some of its unique traits indicated that its bamboo diet might be more dependent on its gut microbiome than its own genetic composition. We also identified more than 2.7 million heterozygous single nucleotide polymorphisms in the diploid genome. Our data and analyses provide a foundation for promoting mammalian genetic research, and demonstrate the feasibility for using next-generation sequencing technologies for accurate, cost-effective and rapid de novo assembly of large eukaryotic genomes.

The diploid genome sequence of an Asian individual.

Here we present the first diploid genome sequence of an Asian individual. The genome was sequenced to 36-fold average coverage using massively parallel sequencing technology. We aligned the short reads onto the NCBI human reference genome to 99.97% coverage, and guided by the reference genome, we used uniquely mapped reads to assemble a high-quality consensus sequence for 92% of the Asian individual's genome. We identified approximately 3 million single-nucleotide polymorphisms (SNPs) inside this region, of which 13.6% were not in the dbSNP database. Genotyping analysis showed that SNP identification had high accuracy and consistency, indicating the high sequence quality of this assembly. We also carried out heterozygote phasing and haplotype prediction against HapMap CHB and JPT haplotypes (Chinese and Japanese, respectively), sequence comparison with the two available individual genomes (J. D. Watson and J. C. Venter), and structural variation identification. These variations were considered for their potential biological impact. Our sequence data and analyses demonstrate the potential usefulness of next-generation sequencing technologies for personal genomics.