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1.
J Control Release ; 354: 588-605, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36657601

RESUMO

Cell spheroids offer cell-to-cell interactions and show advantages in survival rate and paracrine effect to solve clinical and biomedical inquiries ranging from tissue engineering and regenerative medicine to disease pathophysiology. Therefore, cell spheroids are ideal vehicles for gene delivery. Genetically modified spheroids can enhance specific gene expression to promote tissue regeneration. Gene deliveries to cell spheroids are via viral vectors or non-viral vectors. Some new technologies like CRISPR/Cas9 also have been used in genetically modified methods to deliver exogenous gene to the host chromosome. It has been shown that genetically modified cell spheroids had the potential to differentiate into bone, cartilage, vascular, nerve, cardiomyocytes, skin, and skeletal muscle as well as organs like the liver to replace the diseased organ in the animal and pre-clinical trials. This article reviews the recent articles about genetically modified spheroid cells and explains the fabrication, applications, development timeline, limitations, and future directions of genetically modified cell spheroid.

2.
Int J Infect Dis ; 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36682682

RESUMO

OBJECTIVES: To evaluate the safety, immunogenicity and lot-to-lot consistency of sIPV in a 5-dose vial presentation. METHODS: Stage 1 was an open-label safety observation, in which 72 healthy subjects (incl., 24 adults, children, and infants each) were given one or three doses of the 5-dose vial sIPV; stage 2 was a randomized, blinded and positive-control study, in which 1,500 infants were randomized at the ratio of 1:1:1:1:1 into 5 groups to receive either three doses of the 5-dose sIPV three lots, a conventional IPV or a single-dose sIPV as controls, for primary immunization. Safety, immunogenicity and lot-to-lot consistency were assessed. RESULTS: Among 1,456 subjects completed the primary immunization, the GMT ratios of types 1,2,3 of each pair of lots were all within the equivalence criteria margin (0.67-1.50). The seroconversion rates of types 1,2,3 in the combined test group were 98.02%, 94.07%, and 98.77% respectively, non-inferior to both control groups. The overall incidence of adverse reactions (ARs) was 29.68% and erythema was the most common ARs with incidences of 10.47%,9.33%, and 9.73% in the combined test group, and control groups (p>0.05). CONCLUSIONS: The 5-dose sIPV demonstrated good safety, immunogenicity, and lot-to-lot consistency. REGISTRATION: This study has been registered at ClinicalTrials.gov (NCT05386810).

3.
Signal Transduct Target Ther ; 8(1): 20, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596779

RESUMO

An ongoing randomized, double-blind, controlled phase 2 trial was conducted to evaluate the safety and immunogenicity of a mosaic-type recombinant vaccine candidate, named NVSI-06-09, as a booster dose in subjects aged 18 years and older from the United Arab Emirates (UAE), who had administered two or three doses of inactivated vaccine BBIBP-CorV at least 6 months prior to enrollment. The participants were randomly assigned with 1:1 to receive a booster dose of NVSI-06-09 or BBIBP-CorV. The primary outcomes were immunogenicity and safety against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant, and the exploratory outcome was cross-immunogenicity against other circulating strains. Between May 25 and 30, 2022, 516 adults received booster vaccination with 260 in NVSI-06-09 group and 256 in BBIBP-CorV group. Interim results showed a similar safety profile between two booster groups, with low incidence of adverse reactions of grade 1 or 2. For immunogenicity, by day 14 post-booster, the fold rises in neutralizing antibody geometric mean titers (GMTs) from baseline elicited by NVSI-06-09 were remarkably higher than those by BBIBP-CorV against the prototype strain (19.67 vs 4.47-fold), Omicron BA.1.1 (42.35 vs 3.78-fold), BA.2 (25.09 vs 2.91-fold), BA.4 (22.42 vs 2.69-fold), and BA.5 variants (27.06 vs 4.73-fold). Similarly, the neutralizing GMTs boosted by NVSI-06-09 against Beta and Delta variants were also 6.60-fold and 7.17-fold higher than those by BBIBP-CorV. Our findings indicated that a booster dose of NVSI-06-09 was well-tolerated and elicited broad-spectrum neutralizing responses against divergent SARS-CoV-2 variants, including Omicron and its sub-lineages.


Assuntos
COVID-19 , Vacinas , Adulto , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle
4.
Oral Dis ; 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36620868

RESUMO

The electrophysiological function of the tongue involves complicated activities in taste sense, producing the perceptions of salty, sweet, bitter, and sour. However, therapies and prevention of taste loss arising from dysfunction in electrophysiological activity require further fundamental research. Optogenetics has revolutionized neuroscience and brought the study of sensory system to a higher level in taste. The year 2022 marks a decade of developments of optogenetics in taste since this technology was adopted from neuroscience and applied to the taste research. This review summarizes a decade of advances that define near-term translation with optogenetic tools, and newly-discovered mechanisms with the applications of these tools. The main limitations and opportunities for optogenetics in taste research are also discussed.

5.
Bioeng Transl Med ; 8(1): e10334, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684075

RESUMO

Cell aggregates that mimic in vivo cell-cell interactions are promising and powerful tools for tissue engineering. This study isolated a new, easily obtained, population of mesenchymal stem cells (MSCs) from rat hard palates named hard palatal-derived mesenchymal stem cells (PMSCs). The PMSCs were positive for CD90, CD44, and CD29 and negative for CD34, CD45, and CD146. They exhibited clonogenicity, self-renewal, migration, and multipotent differentiation capacities. Furthermore, this study fabricated scaffold-free 3D aggregates using light-controlled cell sheet technology and a serum-free method. PMSC aggregates were successfully constructed with good viability. Transplantation of the PMSC aggregates and the PMSC aggregate-implant complexes significantly enhanced bone formation and implant osseointegration in vivo, respectively. This new cell resource is easy to obtain and provides an alternative strategy for tissue engineering and regenerative medicine.

6.
Front Med (Lausanne) ; 9: 1088592, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530907

RESUMO

Three-dimensional (3D) printing technology involves the application of digital models to create 3D objects. It is used in construction and manufacturing and has gradually spread to medical applications, such as implants, drug development, medical devices, prosthetic limbs, and in vitro models. The application of 3D printing has great prospects for development in orthopedics, maxillofacial plastic surgery, cardiovascular conditions, liver disease, and other fields. With in-depth research on 3D printing technology and the continuous update of printing materials, this technology also shows broad development prospects in renal medicine. In this paper, the author mainly summarizes the basic theory of 3D printing technology, its research progress, application status, and development prospect in renal diseases.

7.
Front Surg ; 9: 928659, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386538

RESUMO

Background: The inflammation and nutrition status are crucial factors influencing the outcome of patients with gastric cancer. This study aims to investigate the prognostic value of the preoperative prognostic nutritional index (PNI) in patients with stage I-III gastric cancer undergoing robotic radical gastrectomy combined with Enhanced Recovery after Surgery (ERAS), and further to create a clinical prognosis prediction model. Study: 525 patients with stage I-III gastric cancer who underwent ERAS combined with RRG from July 2010 to June 2018 were included in this work, and were divided randomly into training and validating groups in a 7-to-3 ratio. The association between PNI and overall survival (OS) was assessed by Kaplan-Meier analysis and the log-rank test. Independent risk factors impacting postoperative survival were analyzed with the Cox proportional hazards regression model. A nomogram for predicting OS was constructed based on multivariate analysis, and its predictive performance was evaluated using Harrell's concordance index (C-index), calibration plots, ROC curve, decision curve analysis (DCA), and time-dependent ROC curve analysis. Results: Survival analyses revealed the presence of a significant correlation between low preoperative PNI and shortened postoperative survival (P = 0.001). According to multivariate analysis, postoperative complications (P < 0.001), pTNM stage (II: P = 0.007; III: P < 0.001), PNI (P = 0.048) and lymph node ratio (LNR) (P = 0.003) were independent prognostic factors in patients undergoing ERAS combined with RRG. The nomogram constructed based on PNI, pTNM stage, complications, and LNR was superior to the pTNM stage model in terms of predictive performance. The C-indexes of the nomogram model were respectively 0.765 and 0.754 in the training and testing set, while AUC values for 1-year, 3-year, and 5-year OS were 0.68, 0.71, and 0.74 in the training set and 0.60, 0.67, and 0.72 in the validation set. Conclusion: Preoperative PNI is an independent prognostic factor for patients with stage I-III gastric cancer undergoing ERAS combined with robotic radical gastrectomy. Based on PNI, we constructed a nomogram for predicting postoperative outcomes of gastric cancer patients, which might be utilized clinically.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36346662

RESUMO

OBJECTIVES: This retrospective study aimed to evaluate early and late implant loss rates after transcrestal sinus floor elevation (TSFE) and to identify the risk factors related to these failures. MATERIAL AND METHODS: All patients treated with TSFE and simultaneous implant placement during October 2015 to March 2019 were evaluated for inclusion. A total of 802 patients with 976 implants met the inclusion criteria. Clinical and radiographic information was collected from medical records and image software. Univariate and multivariate Cox proportional hazards frailty regression models were performed to identify potential risk factors associated with early and late implant loss after TSFE. RESULTS: The 3-year cumulative implant survival rate was 96.9% (95% CI 95.8%-98.0%). Twelve implants in 12 patients were lost before or at the abutment connection, while 24 implants in 24 patients were lost after functional loading. The Cox frailty regression analyses indicated that two factors were correlated with early implant loss: TSFE with grafting materials, and operators with less clinical experience. As for late implant loss, RBH ≤6 mm, male sex, and certain implant brands were associated with a significantly increased failure rate. CONCLUSIONS: Transcrestal sinus floor elevation with simultaneous implant placement is a predictable treatment option in the atrophic maxilla. The presence of grafting materials and the lack of clinical experience of the surgeon were possibly associated with early implant loss, while low RBH, male sex, and certain implant brands tended to increase late implant loss.

9.
J Biomed Mater Res A ; 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36355784

RESUMO

Bone marrow mesenchymal stem cell sheet-derived spheroids (BMSCs spheroids) have been widely studied as native bioactive scaffolds. However, the abundant cells in BMSCs spheroids cause immunogenicity and make them difficult to store. This paper aimed to construct a new bioactive scaffold called 3D-decellularized extracellular matrix spheroids (ECM spheroids) via decellularization of BMSCs spheroids to enhance bone formation. Hematoxylin and eosin staining (HE), nuclear and cytoskeletal fluorescence, immunofluorescence (IF), and scanning electron microscopy (SEM) were utilized to detect the characteristics and components of ECM spheroids. Furthermore, the biological properties of migration, adhesion, and recellularization of cells in ECM spheroids were assessed in vitro, and bone formation was evaluated in rat calvarial defects. The results showed that both the nuclei and cytoskeleton in ECM spheroids were greatly altered and one of the major components of FN was intact. The migration, adhesion, and recellularization potential were improved in vitro. Meanwhile, ECM spheroids promoted osteogenesis in rat skull defects after 3 months (p < .01). In conclusion, ECM spheroids were successfully prepared and proven to promote cell migration, adhesion, and proliferation. Bone formation in vivo was also accelerated. We believe that ECM spheroids can be used as bioactive and biocompatible 3D scaffolds in the future.

10.
Hum Vaccin Immunother ; : 2135929, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36441137

RESUMO

Previous phase I to III clinical trials have shown that the inactivated SARS-CoV-2 vaccine namely CoronaVac has good efficacy, safety, and immunogenicity. This phase IV trial aims to evaluate the lot-to-lot consistency, immunogenicity, and safety on a commercial scale in healthy adults, which could provide data to support stable manufacturing. In this single-center, randomized, double-blind study, 1,080 healthy adults aged 26-45 years were randomly assigned into three groups to receive one of three lots of vaccines. All subjects received two doses of CoronaVac with an interval of 28 days. Serum samples were collected before the first dose and 28 days after the second dose to assess the immunogenicity. Solicited local and systemic adverse events (AEs) within 7 days and unsolicited AEs within 28 days after each dose of vaccination were recorded. A total of 1,039 participants completed the study and were included in the per-protocol set (PPS). The GMTs were 75.2 (68.5,82.6), 65.0 (59.0,71.7), and 65.3 (59.4,71.8), respectively, and the seroconversion rates of neutralizing antibody were all higher than 98%. The GMT ratios of each pair of lots were 1.16 (1.01,1.32), 1.15 (1.01, 1.32), and 0.99 (0.87, 1.14), respectively, meeting the immunological equivalence criteria. The incidence rates of adverse reactions (ARs) were 19.17%, 13.89%, and 18.33%, with no statistical difference. The ARs were all in grade 1 and grade 2, with incidences of 15.46% and 2.50%. Non-vaccine-related serious adverse events (SAEs) were reported. These results showed robust lot-to-lot consistency, immunogenicity, and safety. The stable production indicated that CoronaVac is suitable for large-scale use.Trial registration number: NCT04894227 (ClinicalTrials.gov).

11.
GM Crops Food ; 13(1): 355-371, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36420791

RESUMO

Rice-based products exported from China to Europe have repeatedly encountered technical trade barriers. Using panel data from 24 states of the European Union during 2001-2017, this study builds a theoretical model to investigate the impact of implementation, intensity and structure of the Rapid Alert System for Food and Feed (RASFF) on China-EU rice-based product trade. The study found that RASFF has a serious inhibitory effect on the trade of traditional rice-based products because of detecting GM ingredients, showing an obvious lag effect, diffusion effect and structure effect. The negative effect occurs in entry process, and the inhibitory effect of border rejection and information notifications results in time lag, but the marginal effect of alerts for market links is insignificant. Moreover, the positive information disclosure effect of technical barriers implemented by individual members is much smaller than the negative diffusion effect. Finally, countermeasures and suggestions are proposed, including the source supervision of the test, the supervision of GM variety approval and GM seed production, the establishment of an early-warning and rapid-response mechanism to technical barriers of agricultural products, and food enterprise information.


Assuntos
Oryza , Oryza/genética , Alimentos , China , Inocuidade dos Alimentos/métodos , Contaminação de Alimentos/análise
12.
Acta Biomater ; 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36435441

RESUMO

The application of mesenchymal stem cell (MSC)-based therapy is expected to make a significant contribution to the improvement of epithelial sealing around implants. However, there is currently no optimal MSC delivery biomaterial for clinical application in peri-implant epithelium (PIE) integration. In this study, we show that injectable photo-cross-linkable porous gelatin methacryloyl (GelMA)/silk fibroin glycidyl methacrylate (SilMA) hydrogels encapsulating gingival tissue-derived MSCs (GMSCs) are a simple and practical approach for re-epithelization applications. The hydrogels played a prominent role in supporting the proliferation, survival, and spread of GMSCs. Moreover, it was found that GMSCs-laden Porous GelMA/SilMA hydrogels could significantly upregulate the hemidesmosomes (HDs)-related genes and proteins expression and promote M2 polarization while inhibiting M1 polarization in vitro. Based on a rat model of early implant placement, application of the MSC-loaded hydrogels could enhance the protein expression of LAMA3 and BP180 (COL17A1) at the implant-PIE interface and reduce horseradish peroxidase (HRP) penetration between the implants and PIE. Noticeably, hydrogel-based MSC therapy contributed to augmenting M2 macrophage infiltration at two time points in the gingival connective tissue around implants. These findings demonstrated that GMSCs-laden Porous GelMA/SilMA hydrogels could facilitate epithelial sealing around implants and M2-polarized macrophages and may be a novel and facile therapeutic strategy for implant-PIE integration. STATEMENT OF SIGNIFICANCE: In the case of poor integration between the implant and gingival epithelium, peri-implantitis can develop, which is one of the main causes of implant failure. While stem cell therapy has tremendous potential for addressing this issue, poor cell survival and engraftment compromise the effectiveness of the therapy. Due to the excellent modifiable and tunable properties of gelatin and silk fibroin, injectable photo-cross-linkable porous hydrogels were developed using gelatin methacryloyl (GelMA) and silk fibroin glycidyl methacrylate (SilMA) as delivery vehicles for gingiva-derived MSCs (GMSCs). Porous GelMA/SilMA not only enhanced the proliferation and viability of GMSCs but also promoted their immunomodulatory capability for favorable epithelial sealing around implants. Overall, GMSCs-seeded porous hydrogels could be promising strategies for re-epithelization treatment.

13.
Adv Mater ; : e2207691, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36193772

RESUMO

CO2 electrocatalytic reduction (CO2 ER) to multicarbon (C2+ ) products is heavily pursued because of their commercial values, and the efficiency and selectivity have both attracted tremendous attention. A flow-cell is a device configuration that can greatly enhance the conversion efficiency but requires catalysts to possess high electrical conductivity and gas permeability; meanwhile, the catalysts should enable the reaction pathway to specific products. Herein, it is reported that V-doped Cu2 Se nanotubes with a hierarchical structure can be perfectly compatible with flow-cells and fulfil such a task, achieving CO2 electroreduction to ethanol with high efficiency and selectivity. As revealed by the experimental characterization and theoretical calculation, the substitutional vanadium doping alters the local charge distribution of Cu2 Se and diversifies the active sites. The unique active sites promote the formation of bridge *COB and its further hydrogenation to *COH, and, as such, the subsequent coupling of *COH and *COL eventually generates ethanol. As a result, the optimal Cu1.22 V0.19 Se nanotubes can electrocatalyze CO2 to ethanol with a Faradaic efficiency of 68.3% and a partial current density of -207.9 mA cm-2 for the single liquid product of ethanol at -0.8 V in a flow-cell. This work provides insights into the materials design for steering the reaction pathway toward C2+ products, and opens an avenue for flow-cell CO2 ER toward a single C2+ liquid fuel.

14.
Clin Oral Implants Res ; 33(11): 1098-1113, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36062937

RESUMO

OBJECTIVES: To retrospectively compare multilevel volumetric changes in both hard and soft tissues between antral pseudocyst (AP) removal and retainment before maxillary sinus floor augmentation (MSFA) and immediate implant placement. MATERIAL AND METHODS: Twenty-six patients with 38 implants placed from 2016 to 2021 were included and divided according to a cohort design as follows: 13 removing the cyst (RC group) and 13 "leaving alone" the cyst (LC group). 3D radiographic parameters (primary outcome), 2D parameters and clinical records (secondary outcome) involving both hard and soft tissues were evaluated for four periods (T1: immediate postoperative, T2: 6-month, T3: 12-month, and T4: 2- to 5- year follow-up). Possible confounding factors, including sinus anatomical features and implant distribution, were also analyzed to eliminate their disturbance. RESULTS: The 3D volumetric change rate of bone grafts in the RC group (-9.32% ± 10.01%) from T2 to T3 was significantly lower than that in the LC group (-19.8% ± 10.59%) (p < .05). The change rate of apical bone height (ABH), endo-sinus bone gain (ESBG) and other 2D parameters were not significantly different between the two groups. 5.3% implants in RC group and 9.1% implants in LC group failed during follow-ups. 0% postoperative complications were observed in RC group. The Schneiderian membrane of RC group was significantly thinner than that of LC group at two measuring points in sinus. CONCLUSION: The present study demonstrated that compared to AP retainment, AP removal before MSFA and immediate implant placement can obtain higher bone graft volumetric stability and favorable prognosis.


Assuntos
Cistos , Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Humanos , Estudos Retrospectivos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Transplante Ósseo , Cistos/diagnóstico por imagem , Cistos/cirurgia , Implantação Dentária Endóssea
15.
Polymers (Basel) ; 14(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080634

RESUMO

To improve the recycle value of waste paper and promote circular economic development, waste corrugated paper fiber (WCPF) was used as a reinforcing agent to prepare waste corrugated paper fiber/polylactic acid (WCPF/PLA) composites via dichloromethane solvent which can be reused. The WCPF in the waste corrugated paper is extracted by beating in a Valli beating machine for different time lengths and grinding in a disc grinder. The effects of beating time and the content of WCPF on the microstructure, mechanical properties, thermal decomposition process, and crystallization properties of the WCPF/PLA composite were studied. The result shows that the WCPF can be well separated from each other and can be evenly dispersed in the PLA matrix. When 25 wt% WCPF which was beat for 30 min was used, the composite has the greatest improvement in tensile property. This study provides a new process for the recycling of waste paper in the application of polymer reinforcement. The research on waste paper fiber and degradable polymer composite is of great significance for reducing environmental pollutants and developing circular economy.

16.
Science ; 377(6614): 1555-1561, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36173852

RESUMO

Hydrocarbon separation relies on energy-intensive distillation. Membrane technology can offer an energy-efficient alternative but requires selective differentiation of crude oil molecules with rapid liquid transport. We synthesized multiblock oligomer amines, which comprised a central amine segment with two hydrophobic oligomer blocks, and used them to fabricate hydrophobic polyamide nanofilms by interfacial polymerization from self-assembled vesicles. These polyamide nanofilms provide transport of hydrophobic liquids more than 100 times faster than that of conventional hydrophilic counterparts. In the fractionation of light crude oil, manipulation of the film thickness down to ~10 nanometers achieves permeance one order of magnitude higher than that of current state-of-the-art hydrophobic membranes while retaining comparable size- and class-based separation. This high permeance can markedly reduce plant footprint, which expands the potential for using membranes made of ultrathin nanofilms in crude oil fractionation.

17.
Acta Biomater ; 153: 585-595, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36167235

RESUMO

As an alternative strategy to achieve the desired bone augmentation, tenting screw technology (TST) has considerably broadened the indications for implant treatment. Titanium tenting screws are typically used in TST to maintain the space for bone regeneration. However, a high degree of osteogenic integration complicate titanium tenting screw removal and impact the bone healing micro-environment. Previous efforts have been focused on modifying titanium surfaces to enhance osseointegration while ignoring the opposite process. Due to the vital role of bone marrow mesenchymal stem cells (BMSCs) in bone regeneration, it might be feasible to reduce osseointegration around titanium tenting screws by resisting the adhesion of BMSCs. Herein, poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was incorporated with a Ti surface in terms of surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The cell apoptosis analysis showed that the new surface would not induce the apoptosis of BMSCs. Then, the adhesive and proliferative behaviors of BMSCs on the surface were analyzed which indicated that the poly(PEGMA) surface could inhibit the proliferation of BMSCs through resisting the adhesion process. Furthermore, in vivo experiments revealed the presence of the poly(PEGMA) on the surface resulted in a lower bone formation and osseointegration compared with the Ti group. Collectively, this dense poly(PEGMA) surface of Ti may serve as a promising material for clinical applications in the future. STATEMENT OF SIGNIFICANCE: The poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was grafted onto a Ti surface by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The PEGMA surface could reduce the osteogenic integration by preventing the adhesion of cells, resulting in a lower pullout force of the modified implant and thereby desirable and feasible applications in dental surgery.


Assuntos
Incrustação Biológica , Células-Tronco Mesenquimais , Éteres Metílicos , Osseointegração , Titânio/farmacologia , Incrustação Biológica/prevenção & controle , Metacrilatos/farmacologia , Metacrilatos/metabolismo , Polietilenoglicóis/farmacologia , Polietilenoglicóis/metabolismo , Éteres Metílicos/metabolismo , Propriedades de Superfície , Células da Medula Óssea/metabolismo
18.
Nature ; 609(7925): 58-64, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045237

RESUMO

Polymer membranes are widely used in separation processes including desalination1, organic solvent nanofiltration2,3 and crude oil fractionation4,5. Nevertheless, direct evidence of subnanometre pores and a feasible method of manipulating their size is still challenging because of the molecular fluctuations of poorly defined voids in polymers6. Macrocycles with intrinsic cavities could potentially tackle this challenge. However, unfunctionalized macrocycles with indistinguishable reactivities tend towards disordered packing in films hundreds of nanometres thick7-9, hindering cavity interconnection and formation of through-pores. Here, we synthesized selectively functionalized macrocycles with differentiated reactivities that preferentially aligned to create well-defined pores across an ultrathin nanofilm. The ordered structure was enhanced by reducing the nanofilm thickness down to several nanometres. This orientated architecture enabled direct visualization of subnanometre macrocycle pores in the nanofilm surfaces, with the size tailored to ångström precision by varying the macrocycle identity. Aligned macrocycle membranes provided twice the methanol permeance and higher selectivity compared to disordered counterparts. Used in high-value separations, exemplified here by enriching cannabidiol oil, they achieved one order of magnitude faster ethanol transport and threefold higher enrichment than commercial state-of-the-art membranes. This approach offers a feasible strategy for creating subnanometre channels in polymer membranes, and demonstrates their potential for accurate molecular separations.

19.
J Mol Histol ; 53(5): 793-804, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36002678

RESUMO

Periodontal ligament stem cells (PDLSCs) plays an important role in tissue engineering. As the age increased, the cell viability and osteogenic differentiation of PDLSCs all decreased. Low density lipoprotein receptor related protein 5 (LRP5) was found to promote bone marrow mesenchymal stem cells osteogenic differentiation. Therefore, our study explored the effect of LRP5 on normal and aged PDLSCs and relative mechanism. Here, we found that the expression of LRP5 in PDLSCs of 24 week-old mice was decreased compared with PDLSCs of 5 week-old mice (n = 5). . LRP5 overexpression in PDLSCs increased the intensity of alkaline phosphatase and alizarin red staining, accompanied with upregulated the levels of RUNX family transcription factor 2, collagen type I, and ß-Catenin. LRP5 knockdown displayed the opposite results in PDLSCs in vitro. LRP5 overexpression in aged PDLSCs restored part ability of osteogenic differentiation. Meantime, LRP5 increased the protein expression of phosphorylation of mammalian target of rapamycin (p-mTOR) in normal and aged PDLSCs. Immunofluorescence showed that LRP5 increased the accumulation of p-mTOR nucleus. The effect of LRP5 in promoting osteogenic differentiation of PDLSCs can be antagonized by mTOR inhibitor rapamycin. These findings suggest that LRP5 positively regulate osteogenic differentiation of normal and aged PDLSCs and may be a potential target for enlarging the application of PDLSCs in tissue regeneration.


Assuntos
Osteogênese , Ligamento Periodontal , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Mamíferos , Camundongos , Células-Tronco , Serina-Treonina Quinases TOR
20.
Polymers (Basel) ; 14(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35956624

RESUMO

To improve the performance and application value of recycled plastics, filling modification has been widely used in waste plastic reinforcement. In this study, recycled polyethylene (RPE) was reinforced via extrusion blending using waste polyester fiber (WPF) from a waste silk wadding quilt as a reinforcer. The effects of the amount of WPF on the mechanical properties, the thermal stability of RPE and the microstructure of the RPE/WPF composite were studied. The result shows that extrusion blending can evenly disperse WPF in RPE matrix and that WPF can clearly improve the tensile strength, flexural modulus, storage modulus and thermal stability of RPE. The tensile strength and flexural modulus almost achieved the maximum when the addition of WPF was 20 wt%. The storage modulus under this condition is also higher than that of other samples. This study provides a cheap and effective reinforcement method for waste plastics as well as a new idea for the reuse of WPF, which is of great significance to the reuse of waste and environmental protection. However, how to enhance the interface adhesion between WPF and RPE to further improve the enhancement effect needs further research.

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