Effects of different polymers on biomimetic mineralization of small intestine submu-cosal scaffolds / 北京大学学报(医学版)

Objective:To explore the effects of different polymers on in vitro biomimetic mineralization of small intestinal submucosa(SIS)scaffolds,and to evaluate the physicochemical properties and bio-compatibility of the SIS scaffolds.Methods:The SIS scaffolds prepared by freeze-drying method were im-mersed in simulated body fluid(SBF),mineralized liquid containing polyacrylic acid(PAA)and mine-ralized liquid containing PAA and polyaspartic acid(PASP).After two weeks in the mineralized solu-tion,the liquid was changed every other day.SBF@SIS,PAA@SIS,PAA/PASP@SIS scaffolds were ob-tained.The SIS scaffolds were used as control group to evaluate their physicochemical properties and bio-compatibility.We observed the bulk morphology of the scaffolds in each group,analyzed the microscopic morphology by environment scanning electron microscopy and determined the porosity and pore size.We also analyzed the surface elements by energy dispersive X-ray spectroscopy(EDX),analyzed the struc-ture of functional groups by Flourier transformed infrared spectroscopy(FTIR),detected the water ab-sorption rate by using specific gravity method,and evaluated the compression strength by universal me-chanical testing machine.The pro-cell proliferation effect of each group of scaffolds were evaluated by CCK-8 cell proliferation method.Results:Under scanning electron microscopy,the scaffolds of each group showed a three-dimensional porous structure with suitable pore size and porosity,and crystal was observed in all the mineralized scaffolds of each group,in which the crystal deposition of PAA/PASP@SIS scaffolds was more regular.At the same time,the collagen fibers could be seen to thicken.EDX analysis showed that the characteristic peaks of Ca and P were found in the three groups of mineralized scaffolds,and the highest peaks were found in the PAA/PASP@SIS scaffolds.FTIR analysis proved that all the three groups of mineralized scaffolds were able to combine hydroxyapatite with SIS.All the scaf-folds had good hydrophilicity.The compressive strength of the mineralized scaffold in the three groups was higher than that in the control group,and the best compressive strength was found in PAA/PASP@SIS scaffold.The scaffolds of all the groups could effectively adsorb proteins,and PAA/PASP@SIS group had the best adsorption capacity.In the CCK-8 cell proliferation experiment,the PAA/PASP@SIS scaffold showed the best ability to promote cell proliferation with the largest number of living cells observed.Con-clusion:Compared with other mineralized scaffolds,PAA/PASP@SIS scaffolds prepared by mineralized solution containing both PAA and PASP have better physicochemical properties and biocompatibility and have potential applications in bone tissue engineering.

Study on mechanism of berberine inhibiting tumor stem cells proliferation and its in vivo safety evaluation / 中国药房

OBJECTIVE To investigate the in vitro inhibitory mechanism of berberine on the proliferation of tumor stem cells and evaluate its in vivo safety. METHODS Flow cytometry was used to select tumor stem cells from mouse skin melanoma B16F10 cells； CD44， CD133， Nanog homologous box protein （NANOG） and octamer-binding transcription factor 4 （OCT4） were used as indicators to characterize tumor stem cells. Tumor stem cells were divided into control group， all-trans retinoic acid （ATRA） group， and berberine group， and the CCK-8 method was used to detect the effects of berberine on the viability of tumor stem cells； flow cytometry was adopted to detect cell apoptotic rate， the proportion of CD44+/CD133+ and the positive cell rate of sex determining region Y box protein 2 （SOX2）； the morphological changes of tumor balls were recorded after treatment with berberine； the morphology of cell pyroptosis in each group was recorded， and the release rate of lactate dehydrogenase （LDH） was detected； Western blot assay was adopted to detect the expressions of pyroptosis-related protein gasdermin E （GSDME）， GSDME- N， caspase-3 and cleaved caspase-3. Preliminary evaluation of in vivo safety of berberine was conducted by using zebrafish embryo toxicity experiments. RESULTS Compared with B16F10 cells， the proportion of CD44+/CD133+ cells in tumor stem cells and the fluorescence intensity of NANOG and OCT4 were significantly increased （P＜0.000 1）. The half-inhibitory concentration of berberine to tumor stem cells was 50.98 μmol/L. Compared with the control group， the apoptotic rate of cells in the berberine group was significantly increased， while the proportion of CD44+/CD133+ cells and the rate of SOX2 positive cells were reduced significantly （P＜0.000 1）； tumor stem cell spheroids were atrophied， with partial cell death. After treatment with berberine， tumor stem cells exhibited swelling in their outermost layer， the release rate of LDH of cells was significantly increased and the release rate of LDH increased with increasing dose； the protein expressions of GSDME-N and cleaved-caspase-3 of cells in berberine 20， 40 μmol/L groups were significantly increased， and the protein expressions of GSDME and caspase-3 were significantly reduced （except for berberine 20 μmol/L group， P＜0.05）. The embryonic development of zebrafish treated with berberine was almost unaffected， and the survival rate of embryo reached 100%， with no obvious abnormalities observed. CONCLUSIONS Berberine has good activity against the proliferation of tumor stem cells， and its mechanism of action may be related to activating GSDME and promoting cell pyroptosis； berberine has good in vivo safety.

Oral administration of Bifidobacterium breve improves anti-angiogenic drugs-derived oral mucosal wound healing impairment via upregulation of interleukin-10 / 国际口腔科学杂志·英文版

Recent studies have suggested that long-term application of anti-angiogenic drugs may impair oral mucosal wound healing. This study investigated the effect of sunitinib on oral mucosal healing impairment in mice and the therapeutic potential of Bifidobacterium breve (B. breve). A mouse hard palate mucosal defect model was used to investigate the influence of sunitinib and/or zoledronate on wound healing. The volume and density of the bone under the mucosal defect were assessed by micro-computed tomography (micro-CT). Inflammatory factors were detected by protein microarray analysis and enzyme-linked immunosorbent assay (ELISA). The senescence and biological functions were tested in oral mucosal stem cells (OMSCs) treated with sunitinib. Ligated loop experiments were used to investigate the effect of oral B. breve. Neutralizing antibody for interleukin-10 (IL-10) was used to prove the critical role of IL-10 in the pro-healing process derived from B. breve. Results showed that sunitinib caused oral mucosal wound healing impairment in mice. In vitro, sunitinib induced cellular senescence in OMSCs and affected biological functions such as proliferation, migration, and differentiation. Oral administration of B. breve reduced oral mucosal inflammation and promoted wound healing via intestinal dendritic cells (DCs)-derived IL-10. IL-10 reversed cellular senescence caused by sunitinib in OMSCs, and IL-10 neutralizing antibody blocked the ameliorative effect of B. breve on oral mucosal wound healing under sunitinib treatment conditions. In conclusion, sunitinib induces cellular senescence in OMSCs and causes oral mucosal wound healing impairment and oral administration of B. breve could improve wound healing impairment via intestinal DCs-derived IL-10.

Clinical characteristics and genetic variant analysis of a child with Snijders Blok-Campeau syndrome / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical phenotype and genetic variant of a child with Snijders Blok-Campeau syndrome (SBCS).@*METHODS@#A child who was diagnosed with SBCS in June 2017 at Henan Children's Hospital was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and his parents were collected and the extraction of genomic DNA, which was subjected to trio-whole exome sequencing (trio-WES) and genome copy number variation (CNV) analysis. Candidate variant was verified by Sanger sequencing of his pedigree members.@*RESULTS@#The main clinical manifestations of the child have included language delay, intellectual impairment and motor development delay, which were accompanied with facial dysmorphisms (broad forehead, inverted triangular face, sparse eyebrows, widely spaced eyes, narrow palpebral fissures, broad nose bridge, midface hypoplasia, thin upper lip, pointed jaw, low-set ears and posteriorly rotated ears). Trio-WES and Sanger sequencing revealed that the child has harbored a heterozygous splicing variant of the CHD3 gene, namely c.4073-2A>G, for which both of his parents were of wild-type. No pathogenic variant was identified by CNV testing.@*CONCLUSION@#The c.4073-2A>G splicing variant of the CHD3 gene probably underlay the SBCS in this patient.

Nucleic acid nanoassembly-enhanced RNA therapeutics and diagnosis

RNAs are involved in the crucial processes of disease progression and have emerged as powerful therapeutic targets and diagnostic biomarkers. However, efficient delivery of therapeutic RNA to the targeted location and precise detection of RNA markers remains challenging. Recently, more and more attention has been paid to applying nucleic acid nanoassemblies in diagnosing and treating. Due to the flexibility and deformability of nucleic acids, the nanoassemblies could be fabricated with different shapes and structures. With hybridization, nucleic acid nanoassemblies, including DNA and RNA nanostructures, can be applied to enhance RNA therapeutics and diagnosis. This review briefly introduces the construction and properties of different nucleic acid nanoassemblies and their applications for RNA therapy and diagnosis and makes further prospects for their development.