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1.
Mol Pharm ; 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-33517655

RESUMEN

The HAIYPRH (T7) peptide has been widely used as a ligand for constructing tumor-targeted nanodrug delivery systems since it can target the transferrin receptor (TfR) and then enter cells easily with the help of transferrin (Tf). However, the dynamic mechanism by which transferrin promotes the entry of T7-conjugated nanostructures into cells remains unclear. Herein, a force tracing technique based on atomic force microscopy (AFM) was used to track the ultrafast dynamic process of a T7-conjugated gold nanoparticle (AuNP-T7) entering a cell at the single-particle level in real time. Tf helped decrease the endocytosis force and increase the endocytosis speed of AuNP-T7 in A549 cells. However, Tf only increased the endocytosis speed of AuNP-T7 in HeLa cells. In contrast, in Vero cells without TfR overexpression, Tf decreased the endocytosis speed. This report provides important insights for redesigning and developing T7-conjugated nanodrug carriers in targeted nanodrug delivery systems.

2.
Biochem Pharmacol ; : 114475, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33609560

RESUMEN

Autophagy has become a promising target for cancer therapy. Fangchinoline (Fan) has been shown to exert anticancer effects in some types of cancers. However, the anticancer effects on colorectal cancer (CRC) and the underlying mechanisms have never been elucidated. More specifically, regulation of autophagy in CRC by Fan has never been reported before. In the present study, Fan was found to induce apoptosis and autophagic flux in the CRC cell lines HT29 and HCT116, which was reflected by the enhanced levels of LC3-II protein and p62 degradation, and the increased formation of autophagosomes and puncta formation by LC3-II. Meanwhile, combination with the early-stage autophagy inhibitor 3-methyladenine (3-MA) but not the late-stage autophagy inhibitor chloroquine (CQ) further increased Fan-induced cell death, which suggested the cytoprotective function of autophagy induced by Fan in both HT29 and HCT116 cells. Moreover, Fan treatment demonstrated a dose- and time-dependently increase in the phosphorylation of AMPK and decreasein the phosphorylation of mammalian target of rapamycin (mTOR) and ULK1, leading to the activation of the AMPK/mTOR/ULK1 signaling pathway. Furthermore, in the HT29 xenograft model, Fan inhibited tumor growth in vivo. These results indicate that Fan inhibited CRC cell growth both in vitro and in vivo and revealed a new molecular mechanism involved in the anticancer effect of Fan on CRC, suggesting that Fan is a potent autophagy inducer and might be a promising anticancer agent.

3.
J Appl Microbiol ; 2021 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-33484057

RESUMEN

AIMS: Cellulase-producing Enterococcus species isolated from the rumen of Tibetan yak (Bos grunniens) were characterized, and their combined effects on the silage quality of various forages were studied. METHODS AND RESULTS: The two isolated strains with high cellulolytic potential were identified as Enterococcus faecalis (EF85) and E. faecium (EF83) by 16S rRNA sequencing. Both EF85 and EF83 could grow well at 15-55 °C, pH 3.0-6.0 and in 3.0-6.5% NaCl. The cellulase secreted by EF85 and EF83 showed good stability at temperatures from 20 to 45 °C and pH from 4.5 to 7.0. A commercial inoculant (CLP), a commercial cellulase (CE) and the two cellulolytic strains (EF85+EF83) were added to whole-crop corn, sweet sorghum and Napier grass ensiling for 120 days, respectively. In Napier grass silage, all inoculants significantly increased lactic acid content and ratio of lactic to acetic acid and decreased pH, butyric acid and ammonia nitrogen contents. The acid detergent fibre and cellulose contents in EF85+EF83 treatment were significantly lower than those in the other treatments. In whole-crop corn and sweet sorghum silages, all additives had no significant effect on the fermentation quality, while CE and EF85+EF83 markedly enhanced cellulose degradation and increased free sugar content. CONCLUSION: The combined inoculation of the cellulolytic strain EF85 and EF83 to various forages reduced the fibre content of the resulting silages. SIGNIFICANCE AND IMPACT OF THE STUDY: Few studies involved inoculation of silage with Enterococcus species in different forage types. The isolated cellulolytic strains of E. faecalis EF85 and E. faecium EF83 could be a great alternative for commercial inoculants and enzymes in silage production.

4.
World J Microbiol Biotechnol ; 37(2): 27, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33433734

RESUMEN

This study aimed to evaluate the effects of exogenous epiphytic microbiota inoculation on the fermentation quality and microbial community of sudan grass silage. Gamma irradiated sudan grass was ensiled with distilled water (STR), epiphytic microbiota of sudan grass (SUDm), forage sorghum (FSm), napier grass (NAPm) and whole crop corn (WCCm). The FSm inoculated silage have significantly lower lactic acid (LA) concentration and higher pH during early ensiling, while LA concentration gradually and significantly increased with the progression of ensiling and have lower pH in relation to other treatments for terminal silage. Inoculation of NAPm resulted in lower LA and higher acetic acid (AA) concentrations, higher pH, ammonia-N and dry matter losses for terminal silage, followed by SUDm silage. Inoculations of WCCm significantly increased LA production and pH decline during early ensiling and have higher LA and pH then NAPm and SUDm silages during final ensiling. The early fermentation of SUDm silage was dominated by genus of Pediococcus. The genera of Lactobacillus were predominant in WCCm and NAPm silages during 3 days of ensiling, while Weissella dominated initial microbial community of FS silage. The terminal silage of NAPm was dominated by Enterobacter and Rosenbergiella, while Enterobacter and Lactobacillus dominated terminal SUDm silage. The final silage of FSm was dominated by Lactobacillus, Weissella and Pediococcus, while Lactobacillus and Acetobacter dominated terminal WCCm silages. The results demonstrated that among the four forages the epiphytic microbiota from forage sorghum positively influenced the microbial community and fermentability of sudan grass silage.

5.
J Mater Chem B ; 9(4): 952-957, 2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33437980

RESUMEN

A targeted nano-drug delivery system has provided great potential and benefits to the diagnosis and therapy of cancers. Cell entry is a critical step for taking effect of the targeted nano-drug. In this report, the dynamics of delivering a single aptamer targeted polyamindoamine-camptothecin-AS1411 (PAMAM-CPT-AS1411) nano-drug into cells was investigated using a force tracing technique based on atomic force microscopy. The results show that the specific interaction of AS1411 and nucleolin, which is overexpressed on cancer cells, enhances the efficiency of the PAMAM-CPT-AS1411 cell entry. Moreover, the specific interaction induced receptor-mediated endocytosis prolongs the duration and decreases the speed of a single PAMAM-CPT-AS1411 cell entry, which is helpful to understand the targeted nano-drugs prolonging the therapeutic drug level. However, the required force for PAMAM-CPT-AS1411 cell entry is not changed. This report will provide a novel and potential method for achieving the precise dynamics of targeted nano-drug delivery.

6.
Environ Pollut ; 273: 116467, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33453699

RESUMEN

As zoned areas of industries, industrial parks have great impacts on the environment. Several studies have demonstrated that chemical compounds and heavy metals released from industrial parks can contaminate soil, water, and air. However, as an emerging pollutant, antimicrobial resistance genes (ARGs) in industrial parks have not yet been investigated. Here, we collected soil samples from 35 sites in an industrial park in China and applied a metagenomics strategy to profile the ARGs and virulence factors (VFs). We further compared the relative abundance of ARGs between the sites (TZ_31-35) located in a beta-lactam antimicrobial-producing factory and other sites (TZ_1-30) in this industrial park. Metagenomic sequencing and assembly generated 14, 383, 065 contigs and 17, 631, 051 open reading frames (ORFs). Taxonomy annotation revealed Proteobacteria and Actinobacteria as the most abundant phylum and class, respectively. The 32 pathogenic bacterial genera listed in the virulence factor database (VFDB) were all identified from the soil metagenomes in this industrial park. In total, 685,354 ARGs (3.89% of the ORFs) and 272,694 virulence factors (VFs) (1.55% of the ORFs) were annotated. These ARGs exhibited resistance to several critically important antimicrobials, such as rifampins, fluroquinolones, and beta-lactams. In addition, no significant difference in the relative abundance of ARGs was observed between sites TZ_31-35 and TZ_1-30, indicating that ARGs have already disseminated widely in this industrial park. The present study gave us a better understanding of the whole picture of the resistome and virulome in the soil of the industrial park and suggested that we should treat the industrial park as a whole in the surveillance and maintenance of ARGs.

7.
Cancer Cell Int ; 20(1): 590, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33298069

RESUMEN

BACKGROUND: Although advanced non-squamous non-small cell lung cancer (NSCLC) patients have significantly better survival outcomes after pemetrexed based treatment, a subset of patients still show intrinsic resistance and progress rapidly. Therefore we aimed to use a blood-based protein signature (VeriStrat, VS) to analyze whether VS could identify the subset of patients who had poor efficacy on pemetrexed therapy. METHODS: This study retrospectively analysed 72 advanced lung adenocarcinoma patients who received first-line pemetrexed/platinum or combined with bevacizumab treatment. RESULTS: Plasma samples from these patients were analysed using VS and classified into the Good (VS-G) or Poor (VS-P) group. The relationship between efficacy and VS status was further investigated. Of the 72 patients included in this study, 35 (48.6%) were treated with pemetrexed plus platinum and 37 (51.4%) were treated with pemetrexed/platinum combined with bevacizumab. Among all patients, 60 (83.3%) and 12 (16.7%) patients were classified as VS-G and VS-P, respectively. VS-G patients had significantly better median progression-free survival (PFS) (Unreached vs. 4.2 months; P < 0.001) than VS-P patients. In addition, the partial response (PR) rate was higher in the VS-G group than that in the VS-P group (46.7% vs. 25.0%, P = 0.212). Subgroup analysis showed that PFS was also significantly longer in the VS-G group than that in the VS-P group regardless of whether patients received chemotherapy alone or chemotherapy plus bevacizumab. CONCLUSIONS: Our study indicated that VS might be considered as a novel and valid method to predict the efficacy of pemetrexed-based therapy and identify a subset of advanced lung adenocarcinoma patients who had intrinsic resistance to pemetrexed based regimens. However, larger sample studies are still needed to further confirm this result.

8.
Anim Sci J ; 91(1): e13482, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33277806

RESUMEN

To improve the utilization efficiency of total mixed ration (TMR) on Tibetan plateau, the effects of different additives on fermentation quality and aerobic stability of the ensiled TMR prepared with local feed resources were studied. A total of 150 experimental silos were prepared in a completely randomized design to evaluate the following treatments: (a) control; (b) Lactobacillus buchneri; (c) acetic acid; (d) propionic acid; (e) 1,2-propanediol; and (f) 1-propanol. After 90 days of ensiling, silos were opened for fermentation quality and in vitro parameters analysis, and then subjected to an aerobic stability test for 14 days. The acetic acid, 1,2-propanediol and 1-propanol treatments increased (p < .05) pH and acetic acid content, and lowered (p < .05) the lactic acid production in comparison to control. There were no statistically significant differences in in vitro digestibility parameters among the treatments. Treatments of acetic acid, 1,2-propanediol and 1-propanol substantially improved the aerobic stability of the ensiled TMR, as indicated by almost unchanged pH and lactic acid contents throughout the aerobic exposure test. These results indicated that acetic acid, 1,2-propanediol and 1-propanol had no adverse effect on in vitro digestibility and could be effective additives for enhancing the aerobic stability of ensiled TMR prepared on Tibetan plateau.

9.
Chemosphere ; : 128652, 2020 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-33268094

RESUMEN

In this work, kaolin/steel slag particle electrodes (KSPEs) were synthesized using a calcination method, and they were used to degrade norfloxacin (NOR) wastewater in three-dimensional (3D) reactor. Characterization methods used by KSPEs included SEM, XRF, XRD and BET. The effects of cell voltage, initial pH, KSPEs dosage and initial NOR concentration on NOR degradation were studied in the optimization experiment of operating parameters. The NOR degradation rate and COD removal rate can reach 96.02% and 93.45% under the optimal parameters within 30 min, and energy consumption is 0.99 kWh m-3. As a result, KSPEs shows excellent catalytic performance and cycling, and still has high electrocatalytic activity after 10 cycles. Finally, the degradation mechanism and degradation pathways of KSPEs to treat NOR are proposed.

10.
J Pak Med Assoc ; 70(10): 1727-1730, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33159742

RESUMEN

OBJECTIVE: To investigate the clinical characteristics of early recurrent intussusception after ultrasound-guided saline reduction, and to explore the factors leading to early recurrence. Methods: The retrospective observational case-control study was conducted at Weifang People's Hospital, Shandong, China, and comprised data from January 2015 to December 2017 related to paediatric intussusception patients aged 0-12 years who underwent ultrasound-guided saline enema reduction. The patients were divided into two recurrent and non-recurrent groups. Clinical characteristics of the patients with early recurrence were analysed. Factors compared between the groups were gender, age, onset season, onset-to-treatment time interval, blood in stool, fever, diarrhoea, abdominal pain and vomiting, weight and pathology. Data was analysed using SPSS 22. RESULTS: Of the 672 subjects, 86(13%) were patient with early recurrence while 586(87%) had no early recurrence and acted as controls. Among the patients, 70(81.4%) were aged 6-36 months. In 52(60.5%) patients, recurrence was once, and in 23(26.7%) twice. There were 141 episodes of intussusception; 24(17%) occurring in <12 hours, 85(60.2%) in 12-24 hours. Also, 5(6%) patients required surgery for reduction. Compared to the controls, the second quarter, heavier body weight and pathology were the factors leading to early recurrence of intussusceptions (p<0.05). CONCLUSIONS: The second quarter, heavier body weight and pathological leading points were found to be factors leading to early recurrent intussusception.

11.
Artículo en Inglés | MEDLINE | ID: mdl-33196070

RESUMEN

Bisphenol analogues (BPs) have been widely used in industrial production as substitutes of bisphenol A (BPA). The demand and production of BPs are growing rapidly in China. In this study, the pollution levels and distribution characteristics of five BPs were investigated in surface water from rivers located in different land-use types of an ecological demonstration zone. All BPs were detected at least once in the traditionally dissolved phase, colloidal phase and suspended particulate matter (SPM) with the mean total concentrations of 465.1 ng L-1, 114.4 ng L-1 and 11.3 µg g-1 dry weight, respectively. BPA is the dominant BP in the traditionally dissolved phase and colloidal phase, with the mean contribution rates of 77.6% and 70.7%, respectively, followed by bisphenol F (BPF) and/or bisphenol S (BPS). The colloids as the important sinks of contaminants contributed 42.3% of bisphenol Z, 37.3% of BPF, 24.9% of BPA, 22.3% of BPAF and 18.4% of BPS in the traditionally dissolved phase. However, BPA alternatives are found primarily in the SPM, in which the contribution rate of BPA ranges from 0.6% to 48.1%, with the mean contribution of 12.4%. Based on BP concentrations in the traditionally dissolved phase, moderate ecological risk levels of BPA and BPF towards aquatic organisms were posed. Fish and/or algae are the most sensitive aquatic organisms, and hence chronic toxicological effects should not be ignored especially in fish.

12.
Bioresour Technol ; 320(Pt B): 124341, 2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33217694

RESUMEN

To reduce the cost of lignocellulosic pretreatment, rice straw was ensiled with dilute formic acid (FA, 0, 0.2, 0.4, and 0.6%) for 3, 6, 9, 15 and 30 days, and evaluated its effects on fermentation dynamics, lignocellulosic degradation and enzymatic hydrolysis. The results showed that the application of FA, especially at 0.6% level, reduced total fermentation losses of the resulting silages, as evidenced by low dry matter loss, ammonia nitrogen and ethanol content. Meanwhile, the 0.6% FA application promoted hemicellulose removal (232.41 vs 187.52 g/kg DM) and xylose production (0.35 vs 2.80 g/kg DM). The glucose yield and cellulose convertibility of rice straw increased after 30 days of ensiling, and further enhanced by the 0.6% FA application. In conclusion, the 0.6% FA-assisted ensiling pretreatment improved both biomass preservation, hemicellulose removal and enzymatic hydrolysis of rice straw, which is beneficial to the subsequent biofuel production chain.

13.
R Soc Open Sci ; 7(10): 200857, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33204457

RESUMEN

Residual antibiotics in water are often persistent organic pollutants. The purpose of this study was to prepare a cellulose nanocrystals/graphene oxide composite (CNCs-GO) with a three-dimensional structure for the removal of the antibiotic levofloxacin hydrochloride (Levo-HCl) in water by adsorption. The scanning electron microscope, Fourier transform infrared (FT-IR), energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and other characterization methods were used to study the physical structure and chemical properties of the CNCs-GO. The three-dimensional structure of the composite material rendered a high surface area and electrostatic attraction, resulting in increased adsorption capacity of the CNCs-GO for Levo-HCl. Based on the Box-Behnken design, the effects of different factors on the removal of Levo-HCl by the CNCs-GO were explored. The composite material exhibited good antibiotic adsorption capacity, with a removal percentage exceeding 80.1% at an optimal pH of 4, the adsorbent dosage of 1.0 g l-1, initial pollutant concentration of 10.0 mg l-1 and contact time of 4 h. The adsorption isotherm was well fitted by the Sips model, and kinetics studies demonstrated that the adsorption process conformed to a quasi-second-order kinetics model. Consequently, the as-synthesized CNCs-GO demonstrates good potential for the effective removal of antibiotics such as levofloxacin hydrochloride from aqueous media.

14.
Polymers (Basel) ; 12(11)2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33182432

RESUMEN

In this study, a novel polyurethane porous 3D scaffold based on polyethylene glycol (PEG) and polytetrahydrofuran glycol (PTMG) was developed by in situ polymerization and freeze drying. Aliphatic hexamethylene diisocyanate (HDI) as a nontoxic and safe agent was adopted to produce the rigid segment in polyurethane polymerization. The chemical structure, macrostructure, and morphology-as well as mechanical strength of the scaffolds-were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and tensile tests. The results show that the HDI can react mildly with hydroxyl (-OH) groups of PEG and PTMG, while gas foaming action caused by the release of CO2 occurred simultaneously in the reactive process, resulting in a uniform porous structure of PU scaffold. Moreover, the scaffolds were soaked in water and freeze dried to obtain higher porosity and more interconnective microstructures. The scaffolds have a porosity of over 70% and pore size from 100 to 800 µm. The mechanical properties increased with increasing PEG content, while the hydrophilicity increased as well. After immersion in simulated body fluid (SBF), the scaffolds presented a stable surface structure. The gas foaming/freezing drying process is an excellent method to prepare skin tissue engineering scaffold from PTMG/PEG materials with high porosity and good inter connectivity.

15.
Arthritis Res Ther ; 22(1): 256, 2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-33109253

RESUMEN

BACKGROUND: Emerging evidence suggests that microRNAs (miRs) are associated with the progression of osteoarthritis (OA). In this study, the role of exosomal miR-136-5p derived from mesenchymal stem cells (MSCs) in OA progression is investigated and the potential therapeutic mechanism explored. METHODS: Bone marrow mesenchymal stem cells (BMMSCs) and their exosomes were isolated from patients and identified. The endocytosis of chondrocytes and the effects of exosome miR-136-5p on cartilage degradation were observed and examined by immunofluorescence and cartilage staining. Then, the targeting relationship between miR-136-5p and E74-like factor 3 (ELF3) was analyzed by dual-luciferase report assay. Based on gain- or loss-of-function experiments, the effects of exosomes and exosomal miR-136-5p on chondrocyte migration were examined by EdU and Transwell assay. Finally, a mouse model of post-traumatic OA was developed to evaluate effects of miR-136-5p on chondrocyte degeneration in vivo. RESULTS: In the clinical samples of traumatic OA cartilage tissues, we detected increased ELF3 expression, and reduced miR-136-5p expression was determined. The BMMSC-derived exosomes showed an enriched level of miR-136-5p, which could be internalized by chondrocytes. The migration of chondrocyte was promoted by miR-136-5p, while collagen II, aggrecan, and SOX9 expression was increased and MMP-13 expression was reduced. miR-136-5p was verified to target ELF3 and could downregulate its expression. Moreover, the expression of ELF3 was reduced in chondrocytes after internalization of exosomes. In the mouse model of post-traumatic OA, exosomal miR-136-5p was found to reduce the degeneration of cartilage extracellular matrix. CONCLUSION: These data provide evidence that BMMSC-derived exosomal miR-136-5p could promote chondrocyte migration in vitro and inhibit cartilage degeneration in vivo, thereby inhibiting OA pathology, which highlighted the transfer of exosomal miR-136-5p as a promising therapeutic strategy for patients with OA.

16.
Gene ; : 145253, 2020 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-33098939

RESUMEN

Fibronectin (FN) functions as a potent stimulator of osteogenic differentiation, and bone fracture healing. In FN family, FN1 acts as an interactive protein gene product to mediate chondrocyte adhesion. However, its effect on fracture healing remains elusive. Therefore, we aimed to investigate the involvement of FN1 in fracture healing. Hard callus formations were found at fracture site with thicker periosteum in lateral cortical bone area outside the fracture site in model mice. The decreased number of osteogenic cells in the middle of the callus region and increased extracellular matrix were suggestive of successful induction. Immunoblotting and RT-qPCR revealed that expression of FN1 was increased in tissues of fracture mice. As displayed by Safranin-fast green staining hematoxylin-eosin staining, the overexpression of FN1 at fracture site promoted osteoid formation and chondrocyte differentiation. The stimulating role of FN1 in collagen production was evidenced by increased levels of Col2, Col1, ColX, Osteonectin, and Osteocalcin and enhanced BMD, BV, BV/TV and Tb.Th values verified by immunoblotting and immunohistochemical staining. Additionally, the upregulation of FN1 contributed to promoted TGF-ß, c-Caspase-9/t-Caspase-9 ratio and NF-κB p65 protein expression as well as lowered p-PI3K/PI3K and p-AKT/AKT ratios, implying the positive correlation between FN1 and the TGF-ß/PI3K/Akt signaling pathway. The key findings of the present study provided evidence indicating that overexpression of FN1 contributes to fracture healing by activation of the TGF-ß/PI3K/Akt signaling pathway.

17.
J Bone Miner Metab ; 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33079278

RESUMEN

INTRODUCTION: Recent studies have indicated the potential of stem cell therapy in combination with cytokines to restore the bone repair via migration and homing of stem cells to the defected area. The present study aimed to investigate the mobilization and recruitment of mesenchymal stem cells (MSCs) in response to SDF-1. MATERIALS AND METHODS: Herein, the knockout rat model of the bone defect (BD) was treated with the induced membrane technique. Then, wild type Wistar rats and SDF-1-knockout rats were selected for the establishment of BD-induced membrane (BD-IM) models and bone-graft (BG) models. The number of MSCs was evaluated by flow cytometry, along with the expression pattern of the SDF-1/CXCR4 axis as well as osteogenic factors was identified by RT-qPCR and Western blot analyses. Finally, the MSC migration ability was assessed by the Transwell assay. RESULTS: Our data illustrated that in the induced membrane tissues, the number of MSCs among the BD-IM modeled rats was increased, whereas, a lower number was documented among BG modeled rats. Besides, we found that lentivirus-mediated over-expression of SDF-1 in BG modeled rats could activate the SDF-1/CXCR4 axis, mobilize MSCs into the defect area, and up-regulate the osteogenic proteins. CONCLUSIONS: Collectively, our study speculated that up-regulation of SDF-1 promotes the mobilization and migration of MSCs through the activation of the SDF-1/CXCR4 signal pathway.

18.
Aging (Albany NY) ; 12(20): 19938-19944, 2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-33085645

RESUMEN

COVID-19 shared many symptoms with seasonal flu, and community-acquired pneumonia (CAP) Since the responses to COVID-19 are dramatically different, this multicenter study aimed to develop and validate a multivariate model to accurately discriminate COVID-19 from influenza and CAP. Three independent cohorts from two hospitals (50 in discovery and internal validation sets, and 55 in the external validation cohorts) were included, and 12 variables such as symptoms, blood tests, first reverse transcription-polymerase chain reaction (RT-PCR) results, and chest CT images were collected. An integrated multi-feature model (RT-PCR, CT features, and blood lymphocyte percentage) established with random forest algorism showed the diagnostic accuracy of 92.0% (95% CI: 73.9 - 99.1) in the training set, and 96. 6% (95% CI: 79.6 - 99.9) in the internal validation cohort. The model also performed well in the external validation cohort with an area under the receiver operating characteristic curve of 0.93 (95% CI: 0.79 - 1.00), an F1 score of 0.80, and a Matthews correlation coefficient (MCC) of 0.76. In conclusion, the developed multivariate model based on machine learning techniques could be an efficient tool for COVID-19 screening in nonendemic regions with a high rate of influenza and CAP in the post-COVID-19 era.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Modelos Estadísticos , Neumonía Viral/diagnóstico , Adulto , Algoritmos , Técnicas de Laboratorio Clínico , Diagnóstico Diferencial , Femenino , Humanos , Gripe Humana/diagnóstico , Masculino , Persona de Mediana Edad , Pandemias , Neumonía/diagnóstico , Adulto Joven
19.
Materials (Basel) ; 13(19)2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-32992794

RESUMEN

Heavily doped polysilicon layers have been widely used in the fabrication of microelectromechanical systems (MEMS). However, the investigation of high selectivity, anisotropy, and excellent uniformity of heavily doped polysilicon etching is limited. In this work, reactive ion etching of undoped and heavily doped polysilicon-based hydrogen bromide (HBr) plasmas have been compared. The mechanism of etching of heavily doped polysilicon is studied in detail. The final results demonstrate that the anisotropy profile of heavily doped polysilicon can be obtained based on a HBr plasma process. An excellent uniformity of resistance of the thermocouples reached ± 2.11%. This technology provides an effective away for thermopile and other MEMS devices fabrication.

20.
Commun Biol ; 3(1): 529, 2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32973345

RESUMEN

The treatment of Staphylococcus aureus (S. aureus) infections has become more difficult due to the emergence of multidrug resistance in the bacteria. Here, we report the synthesis of a lawsone (2-hydroxy-1,4-naphthoquinone)-based compound as an antimicrobial agent against methicillin-resistant S. aureus (MRSA). A series of lawsone-derivative compounds were synthesized by means of tuning the lipophilicity of lawsone and screened for minimum inhibitory concentrations against MRSA to identify a candidate compound that possesses a potent antibacterial activity. The identified lawsone-derivative compound exhibited significantly improved drug resistance profiles against MRSA compared to conventional antibiotics. The therapeutic efficacy of the compound was validated using murine models of wound infection as well as non-lethal systemic infection induced by MRSA. Our study further revealed the multifaceted modes of action of the compound, mediated by three distinctive mechanisms: (1) cell membrane damage, (2) chelation of intracellular iron ions, and (3) generation of intracellular reactive oxygen species.

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