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1.
Food Chem ; 334: 127487, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688178

RESUMO

Biodegradable films poly(butylene adipate-co-butylene terephthalate) (PBAT)/poly(lactic acid) (PLA) incorporated with nano-polyhedral oligomeric silsesquioxane (POSS(epoxy)8) as a reactive compatibilizer were developed by melt processing. Structural, morphological, mechanical, and gas permeability properties of the films were determined. 1H NMR and GPC demonstrated that the POSS(epoxy)8 was chemically bound at the PBAT/PLA boundary phase via an epoxide ring opening reaction. SEM micrographs of impact fracture surfaces demonstrated the POSS(epoxy)8 improved interfacial adhesion between PBAT and PLA matrix. The mechanical properties of the PBAT/PLA films containing POSS(epoxy)8 were enhanced relative to pristine PBAT/PLA films. The water vapor, CO2 and O2 permeability of the PBAT/PLA films were improved by POSS(epoxy)8 addition. PBAT/PLA films containing POSS(epoxy)8 were shown to be superior to pristine PBAT/PLA films and polyethylene films in food storage tests. Results suggest that POSS(epoxy)8 addition during PBAT/PLA film production offers a simple strategy for the production of high performance biodegradable plastic packaging films.


Assuntos
Plásticos Biodegradáveis/química , Embalagem de Alimentos/métodos , Nanocompostos/química , Poliésteres/química , Dióxido de Carbono/química , Armazenamento de Alimentos/métodos , Oxigênio/química , Permeabilidade , Resistência à Tração
2.
Physiol Genomics ; 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33197228

RESUMO

Comprehensive and spatially mapped molecular atlases of organs at a cellular level are a critical resource to gain insights into pathogenic mechanisms and personalized therapies for diseases. The Kidney Precision Medicine Project (KPMP) is an endeavor to generate 3-dimensional (3D) molecular atlases of healthy and diseased kidney biopsies using multiple state-of-the-art OMICS and imaging technologies across several institutions. Obtaining rigorous and reproducible results from disparate methods and at different sites to interrogate biomolecules at a single cell level or in 3D space is a significant challenge that can be a futile exercise if not well controlled. We describe a "follow the tissue" pipeline for generating a reliable and authentic single cell/region 3D molecular atlas of human adult kidney. Our approach emphasizes quality assurance, quality control, validation and harmonization across different OMICS and imaging technologies from sample procurement, processing, storage, shipping to data generation, analysis and sharing. We established benchmarks for quality control, rigor, reproducibility and feasibility across multiple technologies through a pilot experiment using common source tissue that was processed and analyzed at different institutions and different technologies. A peer review system was established to critically review quality control measures and the reproducibility of data generated by each technology before being approved to interrogate clinical biopsy specimens. The process established economizes the use of valuable biopsy tissue for multi-OMICS and imaging analysis with stringent quality control to ensure rigor and reproducibility of results and serves as a model for precision medicine projects across laboratories, institutions and consortia.

3.
J Environ Manage ; 278(Pt 2): 111559, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33137686

RESUMO

Given rapid environmental change, the development of new, data-driven, interdisciplinary approaches is essential for improving assessment and management of river systems, especially with respect to flooding. In the world's extensive drylands, difficulties in obtaining field observations of major hydrological events mean that remote sensing techniques are commonly used to map river floods and assess flood impacts. Such techniques, however, are dependent on available cloud-free imagery during or immediately after peak discharge, and single images may omit important flood-related hydrogeomorphological events. Here, we combine multiple Landsat images from Google Earth Engine (GEE) with precipitation datasets and high-resolution (<0.65 m) satellite imagery to visualise flooding and assess the associated channel-floodplain dynamics along a 25 km reach of the unvegetated, ephemeral Río Colorado, Bolivia. After cloud and shadow removal, Landsat surface reflectance data were used to calculate the Modified Normalized Difference Water Index (MNDWI) and map flood extents and patterns. From 2004 through 2016, annual flooding area along the narrow (<30 m), shallow (<1.7 m), fine-grained (dominantly silt/clay) channels was positively correlated (R2 = 0.83) with 2-day maximum precipitation totals. Rapid meander bend migration, bank erosion, and frequent overbank flooding was associated with formation of crevasse channels, splays, and headward-eroding channels, and with avulsion (shifting of flow from one channel to another). These processes demonstrate ongoing, widespread channel-floodplain dynamics despite low stream powers and cohesive sediments. Application of our study approaches to other dryland rivers will help generate comparative data on the controls, rates, patterns and timescales of channel-floodplain dynamics under scenarios of climate change and direct human impacts, with potential implications for improved river management.

4.
BMC Musculoskelet Disord ; 21(1): 769, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33220703

RESUMO

BACKGROUND: Although most cases of humeral shaft nonunion respond well to surgical intervention, surgeons still encounter patients with humeral shaft nonunion who have already undergone repeated surgeries for nonunion. This study retrospectively analyzed the efficacy of double locking compression plate (LCP) fixation in combination with autogenous iliac crest bone grafting for recalcitrant humeral shaft nonunion. METHODS: A consecutive series of patients with aseptic recalcitrant humeral shaft nonunion underwent surgical treatment between May 2010 and August 2017 in our institution. Standardized treatment included thorough debridement, double LCP and screw fixation, and autogenous iliac bone grafting. The injury type and the duration of nonunion were recorded for all patients. The main outcome measurements were the Constant and Murley scale for shoulder function, Mayo elbow performance index (MEPI) for elbow function, and visual analog scale (VAS) for pain. In addition, all complications were documented. RESULTS: The study cohort comprised six females and nine males with a mean age of 45.3 ± 13.1 years. Each patient had already undergone at least one failed surgery for humeral shaft nonunion. The average duration of nonunion before the index intervention was 126.8 ± 124.2 months. All patients achieved bone union without implant failure. At final follow-up, the mean Constant and Murley score and mean MEPI were significantly improved, and the mean VAS score was significantly decreased. Each patient was very satisfied with the treatment. Four patients had complications, including one with a superficial wound infection, one with radial nerve palsy, one with ulnar nerve palsy, and one with discomfort at the iliac crest. CONCLUSION: Double plate fixation combined with autogenous iliac crest bone grafting results in successful salvage of humeral shaft nonunion after prior failed surgical interventions.

5.
Int J Med Sci ; 17(18): 3174-3189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173437

RESUMO

Prolactinomas are the most common type of functional pituitary adenoma. Although bromocriptine is the preferred first line treatment for prolactinoma, resistance frequently occurs, posing a prominent clinical challenge. Both the prolactin receptor (PRLR) and estrogen receptor α (ERα) serve critical roles in the development and progression of prolactinomas, and whether this interaction between PRLR and ERα contributes to bromocriptine resistance remains to be clarified. In the present study, increased levels of ERα and PRLR protein expression were detected in bromocriptine-resistant prolactinomas and MMQ cells. Prolactin (PRL) and estradiol (E2) were found to exert synergistic effects on prolactinoma cell proliferation. Furthermore, PRL induced the phosphorylation of ERα via the JAK2-PI3K/Akt-MEK/ERK pathway, while estrogen promoted PRLR upregulation via pERα. ERα inhibition abolished E2-induced PRLR upregulation and PRL-induced ERα phosphorylation, and fulvestrant, an ERα inhibitor, restored pituitary adenoma cell sensitivity to bromocriptine by activating JNK-MEK/ERK-p38 MAPK signaling and cyclin D1 downregulation. Collectively, these data suggest that the interaction between the estrogen/ERα and PRL/PRLR pathways may contribute to bromocriptine resistance, and therefore, that combination treatment with fulvestrant and bromocriptine (as opposed to either drug alone) may exert potent antitumor effects on bromocriptine-resistant prolactinomas.

6.
Cell ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33152263

RESUMO

We propose that the teratoma, a recognized standard for validating pluripotency in stem cells, could be a promising platform for studying human developmental processes. Performing single-cell RNA sequencing (RNA-seq) of 179,632 cells across 23 teratomas from 4 cell lines, we found that teratomas reproducibly contain approximately 20 cell types across all 3 germ layers, that inter-teratoma cell type heterogeneity is comparable with organoid systems, and teratoma gut and brain cell types correspond well to similar fetal cell types. Furthermore, cellular barcoding confirmed that injected stem cells robustly engraft and contribute to all lineages. Using pooled CRISPR-Cas9 knockout screens, we showed that teratomas can enable simultaneous assaying of the effects of genetic perturbations across all germ layers. Additionally, we demonstrated that teratomas can be sculpted molecularly via microRNA (miRNA)-regulated suicide gene expression to enrich for specific tissues. Taken together, teratomas are a promising platform for modeling multi-lineage development, pan-tissue functional genetic screening, and tissue engineering.

7.
Mol Cancer Res ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172974

RESUMO

DNA methyltransferase inhibitors (DNMTIs) like 5-Azacytidine (5-Aza) are the only disease-modifying drugs approved for the treatment of higher-risk myelodysplastic syndromes (MDS), however less than 50% of patients respond, and there are no predictors of response with clinical utility. Somatic mutations in the DNA methylation regulating gene tet-methylcytosine dioxygenase 2 (TET2) are associated with response to DNMTIs, however the mechanisms responsible for this association remain unknown. Using bisulfite padlock probes, mRNA sequencing, and hydroxymethylcytosine pull-down sequencing at several time points throughout 5-Aza treatment we show that TET2 loss particularly influences DNA methylation (5mC) and hydroxymethylation (5hmC) patterns at erythroid gene enhancers and is associated with down-regulation of erythroid gene expression in the human erythroleukemia cell line TF-1. 5-Aza disproportionately induces expression of these down regulated genes in TET2KO cells and this effect is related to dynamic 5mC changes at erythroid gene enhancers after 5-Aza exposure. We identified differences in remethylation kinetics after 5-Aza exposure for several types of genomic regulatory elements, with distal enhancers exhibiting longer-lasting 5mC changes than other regions. This work highlights the role of 5mC and 5hmC dynamics at distal enhancers in regulating the expression of differentiation-associated gene signatures, and sheds light on how 5-Aza may be more effective in patients harboring TET2 mutations. Implications: TET2 loss in erythroleukemia cells induces hypermethylation and impaired expression of erythroid differentiation genes which can be specifically counteracted by 5-Azacytidine, providing a potential mechanism for the increased efficacy of 5-Aza in TET2-mutant MDS patients.

8.
Transfusion ; 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175455

RESUMO

BACKGROUND: Bombay and para-Bombay phenotypes, which arise from gene mutations of α-1,2-fucosyltransferase FUT1, are very rare in Chinese population. A para-Bombay phenotype Chinese individual with two novel FUT1 mutations was reported here. STUDY DESIGN AND METHODS: The peripheral blood and saliva samples of the proband and her family members were collected after informed consent. ABO and H blood group phenotyping was performed by haemagglutination methods. ABO genotype was determined by PCR-SSP kit. A, B, and H antigens in saliva were detected by a hemagglutination inhibition test. Fragments encompassing the full coding region of FUT1 and FUT2 genes were PCR amplified and sequenced. Allelic sequences were validated by cloning and sequencing individual colonies. RESULTS: The serologic reaction results of the proband revealed that A, B, and H antigen were absent on RBCs, but B and H antigen were presented in saliva, and the serum contains anti-H. The proband was assigned as B/O1 by ABO genotyping. Two new heterozygous mutations of FUT1 gene, c.508dupT and c.787A>C, were identified through direct sequencing of PCR-amplified products. TA cloning and sequencing confirmed that two novel mutations were on different alleles. FUT2 gene sequence of the proband is consistent with standard. The other family members of the proband showed normal phenotypes of ABO blood group and their genotypes are consistent with phenotypes. CONCLUSION: Two novel FUT1 alleles, with the previously not reported mutations c.508dupT and c.787C, respectively, are responsible for the para-Bombay phenotype detected in the sample from the proband.

9.
Org Biomol Chem ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33164006

RESUMO

Under catalyst-free conditions, an efficient method to synthesize 2-pyridinylamides has been developed, and the protocol uses inexpensive and readily available 2-fluoropyridine and amidine derivatives as the starting materials. Simultaneously, the copper-catalysed approach to imidazopyridine derivatives has been established with high chemoselectivity and regiospecificity. The results suggest that the nitrogen-heterocycles containing iodide substituents can also be compatible for the reaction via the cascade Ullmann-type coupling, and the nucleophilic substitution reaction provides the target products in a one-pot manner.

10.
Sci Rep ; 10(1): 20276, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219288

RESUMO

Biomarkers for early diagnosis of hepatocellular carcinoma (HCC) are needed in chronic hepatitis B virus (HBV) infection, a leading cause of HCC. We evaluated whether measurement of serum pentraxin 3 (PTX3) could improve diagnosis of HCC in chronic HBV infection. Data from patients with HBV-related chronic hepatitis (n = 159), cirrhosis (n = 99) and HCC (n = 107), and healthy controls (n = 151) were analyzed. Serum PTX3 concentration was measured by immunoassay. Area under the receiver operating characteristic curve (AUC) was applied to assess diagnostic accuracy. PTX3 levels were significantly higher in HBV patients than in healthy controls (P < 0.001) and in HCC than in chronic hepatitis (P < 0.001) or cirrhosis patients (P < 0.001). PTX3 was an independent risk factor of HCC [odds ratio (OR) 1.617, P < 0.001] and could distinguish HCC in chronic HBV infection [cutoff 9.231 ng/mL, AUC 0.929 with 95% confidence interval (CI) of 0.898-0.953], including α-fetoprotein (AFP) negative [cutoff 8.985 ng/mL, AUC (95%CI) 0.947 (0.908-0.973)] and early-stage HCC [cutoff 9.359 ng/mL, AUC (95%CI) 0.920 (0.885-0.947)]. Combination of PTX3 with AFP improved the discrimination of early HCC from chronic HBV infection [AUC (95%CI) 0.948 (0.918-0.970)]. In short, PTX3 measurement could identify HCC, including AFP-negative and early-stage HCC, in chronic HBV infection.

11.
Cell Tissue Res ; 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33159581

RESUMO

Stem cell transplantation is a promising therapy for wound healing, but the low retention and survival of transplanted stem cells limit their application. Injectable hydrogels exert beneficial effects in skin tissue engineering. In this study, an injectable hydrogel composed of sodium alginate (SA) and collagen type I (Col) was synthesized as a tissue scaffold to improve the efficacy of stem cells in a full-thickness excision wound model. Our results showed that SA/Col hydrogel was injectable, biodegradable, and exhibited low immunogenicity, which could promote the retention and survival of hUC-MSCs in vivo. SA/Col loaded with hUC-MSCs showed reduced wound size (p < 0.05). Histological and immunofluorescence results confirmed that SA/Col loaded with hUC-MSCs significantly promoted the formation of granulation, enhanced collagen deposition and angiogenesis, increased VEGF and TGF-ß1 expression (p < 0.05), and mitigated inflammation evidenced by lower production of TNF-α and IL-1ß and higher release of IL-4 and IL-10 (p < 0.05). Furthermore, SA/Col loaded with hUC-MSCs significantly lowered the expression of NLRP3 inflammasome-related proteins (p < 0.05). Taken together, our results suggest that SA/Col loaded with hUC-MSCs promotes skin wound healing via partly inhibiting NLRP3 pathway, which has potential to the treatment of skin wounds.

12.
Neuroreport ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33165190

RESUMO

MicroRNAs (miRNAs) play important roles in drug tolerance and regulating pain. The purpose of the present study is to explore the regulatory mechanism of miR-124-3p on dezocine tolerance against pain in a rat model. The expression of miR-124-3p and TRAF6 in spinal cord of rats was detected by quantitative reverse-transcription PCR. The paw withdrawal latency (PWL) and maximal potential efficiency % of rats were detected by PWL assay. The levels of IL-1ß and TNF-α in spinal cord tissues of rats were measured by ELISA assay. The interaction between TRAF6 and miR-124-3p was predicted by TargetScan software (http://www.targetscan.org) and confirmed by the dual-luciferase reporter assay. The protein level of TRAF6 was determined by western blot. MiR-124-3p expression was highly downregulated in a dezocine-resistant model. MiR-124-3p overexpression could alleviate dezocine tolerance in rats. TRAF6 expression was significantly upregulated in a dezocine-resistant model. MiR-124-3p targeted TRAF6 and TRAF6 was negatively modulated by miR-124-3p. In addition, overexpression of TRAF6 could reverse the inhibitory effects of miR-124-3p on dezocine tolerance. Overexpression of miR-124-3p alleviates dezocine tolerance against pain via regulating TRAF6 in a rat model, providing a possible solution to address dezocine tolerance in clinical.

13.
BMC Musculoskelet Disord ; 21(1): 739, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183258

RESUMO

BACKGROUND: Previous studies have demonstrated the effectiveness and safety of tranexamic acid (TXA) in orthopedic surgery. However, no study has investigated TXA in complex tibial plateau fracture surgery. Therefore, the purpose of this study was to confirm the safety and effectiveness of i.v. (intravenous) TXA and topical TXA. MATERIAL AND METHODS: This was a retrospective analysis of prospectively collected data. The control group received an equal amount of placebo (physiological saline solution); the i.v. group received 1.0 g TXA by intravenous injection before the tourniquet was inflated and before the surgical incision was closed, and the topical group received 3.0 g TXA in 75 mL of physiological saline solution 5 min prior to the final tourniquet release. Perioperative blood loss, vascular events, wound complications, and adverse reactions were compared among the three groups. The pain, knee function, and quality of life (QoL) assessments were based on their corresponding scoring systems. RESULTS: Baseline data were comparable for all groups. The i.v. group showed the best results for total blood loss (TBL) and hidden blood loss (HBL) (424.5 ± 49.4 mL and 219.3 ± 33.4 mL, respectively, all P values < 0.001). Patients in the i.v. group had lesser real Hb decrease than those in the control group (0.9 vs 1.5, P<0.001) and topical group (0.9 vs 1.2, P = 0.026). The blood coagulation level as measured using fibrinolysis (D-dimer) was lower in the i.v. group than in the control and topical groups on POD1 and POD3; however, this difference was not significant; the fibrin-degradation products also showed a similar trend. Patients in the topical group experienced less pain than those in the control group on POD2, POD4, and PO6W. The VAS pain score was 3.6 vs. 4.4 (POD2, P<0.05), 2.8 vs 3.3 (POD4, P<0.05), and 2.1 vs. 2.6 (PO6W, P<0.001) in the topical group vs control group, respectively. No significant differences were identified in vascular events, wound complications, adverse reactions, knee function, and QoL among the three groups. CONCLUSION: To our knowledge, this is the first study that showed both i.v. TXA and topical TXA are safe and effective for complex tibial plateau fractures. The i.v. regimen effectively reduced blood loss during the perioperative period, whereas patients under the topical regimen had less vascular events, wound complications, and a lower incidence of adverse reactions compared to those in the i.v. group. TRIAL REGISTRATION: The trial was registered in the Chinese Clinical Trial Registry ( ChiCTR-TRC-1800017754 , retrospectively registered from 2018 to 01-01).

14.
Aging (Albany NY) ; 122020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33231567

RESUMO

OBJECTIVE: Tumor necrosis factor superfamily protein 14 (TNFSF14) was recently identified as a risk factor in some fibrosis diseases. However, the role of TNFSF14 in renal fibrosis pathogenesis remains unknown. RESULTS: It was found that TNFSF14 levels were significantly increased both in UUO-induced renal fibrotic mice and in patients with fibrotic nephropathy, compared with those in controls. Accordingly, Tnfsf14 deficiency led to a marked reduction in renal fibrosis lesions and inflammatory cytokines expression in the UUO mice. Furthermore, the levels of Sphk1, a critical molecule that causes fibrotic nephropathy, were remarkably reduced in Tnfsf14 KO mice with UUO surgery. In vitro recombinant TNFSF14 administration markedly up-regulated the expression of Sphk1 of primary mouse renal tubular epithelial cells (mTECs). CONCLUSION: TNFSF14 is a novel pro-fibrotic factor of renal fibrosis, for which TNFSF14 up-regulates Sphk1 expression, which may be the underlying mechanism of TNFSF14-mediated renal fibrosis. METHODS: We investigated the effect of TNFSF14 on renal fibrosis and the relationship between TNFSF14 and pro-fibrotic factor sphingosine kinase 1 (Sphk1) by using the unilateral urethral obstruction (UUO)-induced mice renal fibrosis as a model and the specimen of patients with fibrosis nephropathy, by Masson trichrome staining, immunohistochemistry, qRT-PCR, and western blot analysis.

15.
Int J Mol Med ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33155660

RESUMO

As hyperprolactinemia is observed in patients with bromocriptine­resistant prolactinoma, prolactin (PRL) has been implicated in the development of bromocriptine resistance. Since PRL primarily mediates cell survival and drug resistance via the Janus kinase­2 (JAK2)/signal transducer and activator of transcription 5A (STAT5) signaling pathway, the STAT5 inhibitor, pimozide, may inhibit cell proliferation and reverse bromocriptine resistance in prolactinoma cells. In the present study, compared with bromocriptine or pimozide alone, the combination of pimozide and bromocriptine exerted enhanced reduction in cell growth and proliferation, and increased apoptosis and cell cycle arrest in bromocriptine­resistant prolactinoma cells. A reduction in phospho­STAT5, cyclin D1 and B­cell lymphoma extra­large (Bcl­xL) expression levels were observed in cells treated with the combination of drugs. In addition, pimozide suppressed spheroid formation of human pituitary adenoma stem­like cells, and reduced the protein expression of the cancer stem cell markers, CD133 and nestin. Pimozide did not exert any additional antitumor activity in STAT5­knockdown primary culture cells of human bromocriptine­resistant prolactinomas. Furthermore, Pimozide combined with bromocriptine treatment significantly reduced human prolactinoma xenograft growth. Western blot and immunohistochemical analyses also demonstrated significant inhibition of cell proliferation and stem cell marker proteins in vivo. Collectively, these data indicated that pimozide treatment reduced prolactinoma growth by targeting both proliferating cells and stem cells, at least in part, by inhibiting the STAT5/Bcl­xL and STAT5/cyclin D1 signaling pathways.

16.
Sci Data ; 7(1): 369, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110108

RESUMO

The ratio of plant transpiration to total terrestrial evapotranspiration (T/ET) captures the role of vegetation in surface-atmosphere interactions. However, several studies have documented a large variability in T/ET. In this paper, we present a new T/ET dataset (also including transpiration, evapotranspiration data) for China from 1981 to 2015 with spatial and temporal resolutions of 0.05° and 8 days, respectively. The T/ET dataset is based on a model-data fusion method that integrates the Priestley-Taylor Jet Propulsion Laboratory (PT-JPL) model with multivariate observational datasets (transpiration and evapotranspiration). The dataset is driven by satellite-based leaf area index (LAI) data from GLASS and GLOBMAP, and climate data from the Chinese Ecosystem Research Network (CERN). Observational annual T/ET were used to validate the model, with R2 and RMSE values were 0.73 and 0.07 (12.41%), respectively. The dataset provides significant insight into T/ET and its changes over the Chinese terrestrial ecosystem and will be beneficial for understanding the hydrological cycle and energy budgets between the land and the atmosphere.

17.
J Cosmet Dermatol ; 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33098181

RESUMO

BACKGROUND: Dry skin is a common skin condition caused by reduction of water-holding capacity, which is regulated by skin barrier function. Dry skin can also be a symptom that indicates a more serious diagnosis. There are a number of moisturizers on the market, which play an important role in dermatologic and cosmetic therapies. However, the demand for these products with good and therapeutic efficiency is still growing. AIMS: It remains necessary to investigate the effects of Elaeagnus L gum polysaccharides (EAP), which are prepared from gum of Elaeagnus angustifolia L. on the epidermal permeability barrier function and their possible underlying mechanisms. PATIENTS/METHODS: EAP were purified, analyzed, and tested on human keratinocyte cell line (HaCaT) and then on the skin in vivo to evaluate their antiinflammatory activities and their impacts on impaired skin barrier function. RESULTS: Histological analyses revealed that topical administration with EAP effectively attenuated dryness-like skin condition, including less percutaneous water loss rate, less infiltrate inflammation cells, and less epidermal thickening. Moreover, EAP inhibited the production of various inflammatory mediators and increased AQP-3, FLG, and LOR expression. CONCLUSION: Our results indicated that EAP enhances epidermal permeability barrier function, and they can be used as a promising adjuvant agent in skin care cosmetics and in treating some skin disorders characterized by cutaneous inflammation and abnormal barrier function.

18.
Stem Cell Res Ther ; 11(1): 444, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076979

RESUMO

BACKGROUND: Dysfunction of the DNA methylation was associated with stem cell reprogramming. Moreover, DNA methyltransferase 1 (DNMT1) deficiency was involved in the differentiation of hair follicle stem cell (HFSc), but the molecular mechanisms remain unknown. METHODS: HFSc from human scalp tissues were isolated and cultured. The oil red O staining was used to observe the adipogenesis. The interaction relationship between microRNA (miR)-214-3p and mitogen-activated protein kinase 1 (MAPK1) was accessed by dual-luciferase reporter gene assay. The methylation level of miR-214-3p promoter was detected by methylation-specific PCR and the enrichment of DNMT1 in miR-214-3p promoter by chromatin immunoprecipitation assay. A mouse model of trauma was established to observe the skin regeneration at 0, 6, and 14 days. RESULTS: Expression of DNMT1 and MAPK1 was increased in the HFSc, while the expression of miR-214-3p was reduced. Moreover, DNMT1 inhibited the expression of miR-214-3p by promoting the promoter methylation of miR-214-3p. Overexpression of DNMT1 could reduce the expression of miR-214-3p, but increase the expression of MAPK1 and the extent of extracellular signal regulated kinase (ERK)1/2 phosphorylation, leading to enhanced adipogenic differentiation. Importantly, DNMT1 promoted skin regeneration in vivo. Conversely, overexpression of miR-214-3p could reverse the effects of DNMT1 on adipogenesis of HFSc. CONCLUSION: DNMT1 promotes adipogenesis of HFSc by mediating miR-214-3p/MAPK1/p-ERK1/2 axis. This study may provide novel biomarkers for the potential application in stem cell therapy.

19.
Org Lett ; 22(21): 8589-8592, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33104370

RESUMO

The asymmetric total synthesis of arbornamine was accomplished in 13 steps, leading to the assignment of its absolute configuration. The key features of the strategy include construction of the C16 quaternary carbon center by a highly diastereoselective Grignard reagent addition to N-tert-butanesulfinylimine, sequential site-selective amidation and N-alkylation to form the C and E rings, and [Ni(COD)2]-mediated Michael addition to close the D ring.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33066720

RESUMO

Skin injury is a major problem threatening human physical and mental health, and how to promote wound healing has been the focus. Developing new wound dressings is an important strategy in skin regeneration. Aloe vera is a medicinal plant with a long history, complex constituents, and various pharmacological activities. Many studies have shown that A. vera plays an important role in promoting wound healing. Adding A. vera to wound dressing has become an ideal way. This review will describe the process of skin injury and wound healing and analyze the role of A. vera in wound healing. In addition, the types of wound dressing and the applications of A. vera in wound dressing will be discussed.

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