Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 302
Filtrar
1.
Drug Deliv ; 28(1): 2100-2107, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34596008

RESUMO

Hyperpigmentation is a common complaint and distressing problem in dermatology, and tranexamic acid (TA) is an effective treatment agent but limited by the delivery to melanocytes in the epidermis. Herein, a novel TA naogels (named HA/TA-LP), combining the advantages of liposomes and hyaluronic acid (HA), are prepared and assessed for topical hyperpigmentation treatment with targeting delivery and minimizing epidermal diffusion. Morphological characteristics indicate numerous TA-loaded liposomes packed in HA gels. In vitro cell studies using human A375 melanoma cells show that HA/TA-LP can promote the uptake of TA by targeting delivery with resulting inhibition of tyrosinase activity and melanin production. Guinea pigs are used to construct hyperpigmentation models and investigate the topical delivery and treatment efficacy of HA/TA-LP. In vivo topical delivery studies indicate HA/TA-LP realize the effective delivery into melanocytes with an ideal balance of effective permeability and minimizing epidermal diffusion. Subsequently, hyperpigmentation treatment assessments reveal that HA/TA-LP inhibit tyrosinase activity and melanin production under the radiation of UVB. Our study identifies favorable properties of HA/TA-LP for treating hyperpigmentation, and provides an experimental basis for further clinical application.

2.
Opt Express ; 29(20): 31754-31766, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615262

RESUMO

We demonstrate an adaptive super-resolution based contact imaging on a CMOS chip to achieve subcellular spatial resolution over a large field of view of ∼24 mm2. By using regular LED illumination, we acquire the single lower-resolution image of the objects placed approximate to the sensor with unit magnification. For the raw contact-mode lens-free image, the pixel size of the sensor chip limits the spatial resolution. We develop a hybrid supervised-unsupervised strategy to train a super-resolution network, circumventing the missing of in-situ ground truth, effectively recovering a much higher resolution image of the objects, permitting sub-micron spatial resolution to be achieved across the entire sensor chip active area. We demonstrate the success of this approach by imaging the proliferation dynamics of cells directly cultured on the chip.

3.
Mol Med Rep ; 24(6)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34590153

RESUMO

The morbidity and mortality of pancreatic cancer have been continuously increasing, causing seven deaths per 100,000 individuals/year. At present, effective therapies are severely lacking, thus, highlighting the importance of developing novel therapeutic approaches. The present study aimed to investigate the inhibitory roles of the 2,3­oxidosqualene cyclase inhibitor, RO 48­8071 (RO), on pancreatic ductal adenocarcinoma. RO was used to treat the pancreatic cancer cell line (PANC­1) in vitro to examine the effects of RO on cell viability, as well as to determine its potential molecular mechanism. Moreover, experiments in a xenograft model of subcutaneous tumors generated by injecting PANC­1 cells hypodermically into nude mice were performed to observe the inhibition of RO on tumor growth. It was found that RO inhibited PANC­1 cell viability when treatment was given for 24, 48 and 72 h. The in vivo study demonstrated that RO markedly inhibited subcutaneous tumor growth in nude mice. Further studies revealed that RO could induce cell cycle arrest in the G1 phase by regulating p27, cyclin B1 and cyclin E expression to inhibit PANC­1 cell viability. Moreover, RO inactivated the JNK and ERK MAPK signaling pathway by decreasing the phosphorylation levels of JNK and ERK. Collectively, the present study demonstrated that RO served anti­pancreatic cancer roles in vitro and in vivo, which may provide new ideas and facilitate the development of novel treatment options for pancreatic cancer.

4.
Bioresour Technol ; 342: 125934, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34536839

RESUMO

This study proposed a novel polyoxometalates (POMs)-based pretreatment technology to improve methane production from waste activated sludge (WAS) for the first time. Experimental results indicated methane production from WAS pretreated with 0.25 g POMs/g TSS increased by 43.7%. Mechanism analysis revealed POMs pretreatment promoted WAS disintegration and improved the biodegradability of the released organics. The declined oxidation-reduction potential of digestion system provided a more favorable situation for anaerobes, and hence had positive impacts on the activity of enzymes associated with hydrolysis/acidification/methanogenesis. Model-based analysis elucidated POMs pretreatment remarkably increased both biochemical methane potential and hydrolysis rate. Microbial community analysis showed microbial community was shifted toward increase hydrolytic and acidification-associated microbes and enriched the abundance of Methanosaeta sp. This work is expected to develop an innovative technology that will simultaneously enhance energy production from WAS in the sludge treatment line and improve biological nutrient removal in the wastewater treatment line of WWTPs.

5.
Sci Total Environ ; 804: 149965, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34508937

RESUMO

Ammonium removal in wastewater treatment plants demands large quantities energy input, such as aeration for wastewater and the addition of organics for nitrate reduction. Anaerobic ammonium oxidation coupled to Fe(III) reduction, called Feammox process play a crucial role in natural nitrogen cycle, which has been rarely investigated in the field of wastewater treatment. Besides, Iron-reducing bacteria (FeRB) as function bacteria of Feammox could transfer electrons to iron oxide by oxidizing organics. The possibility of anaerobic ammonium removal coupled with organics should be investigated to assess the potential of Feammox process for conventional wastewater treatment. In this study, five Fe(III) compounds, Fe2O3, Fe3O4, Fe(OH)3, Citrate-Fe and pyrite were supplemented to investigate the effect of iron oxides on ammonium removal in serum bottles with working volume of 100 mL. It was found that ammonium removal efficiency of the Fe2O3 group was the highest. To simulate wastewater treatment process in sewage treatment plant, three Up-flow anaerobic sludge blanket reactors with volume of 250 mL adding Fe2O3 were applied with influent of ammonium and carbon sources. It was found that the organics significantly inhibited the ammonium removal by Feammox process. This was attributed to that carbon sources and ammonium could be used as electron donors for Fe(III) reduction. In addition, this nitrogen removal was also likely related with the iron cycle, i.e., Fe(III) reduction with ammonium oxidation and Fe(II) oxidation with nitrate/nitrite reduction. This study provides a promising alternative technology for anaerobic ammonium removal in wastewater treatment. Optimizing nitrogen removal and carbon sources applied in conventional wastewater plants are required in future.

6.
J Fluoresc ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524573

RESUMO

A chemical sensor that can induce near-infrared red-shifted response represents a promising strategy for the design and development of anion probes. In this work, novel CH-controlled colorimetric probe 3 based on anthracene carboximide was developed for near-infrared detection of cyanide. Probe 3 consisted of CHCN binding site to anthracene carboximide fluorophore, and showed a significant visual change from yellow-green (535 nm) to deep violet (825 nm) with a larger redshift (≈ 290 nm) and fluorescence quenching at 480 nm and 520 nm upon interacting with cyanide. Job curves determined 1:1 binding stoichiometry of probe 3 with cyanide. Additonally, probe 3 detected cyanide ion conveniently in aqueous solution and could be reused after trifluoroacetic acid treatment. Colorimetric test paper was used to detect cyanide in aqueous solutions. The C-H deprotonation sensing mechanism was confirmed by 1H NMR titration. The near-infrared detection of cyanide by CH-controlled probes was founded for the first time.

7.
Sci Rep ; 11(1): 17575, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475424

RESUMO

Absolute risks of stroke are typically estimated using measurements of cardiovascular disease risk factors recorded at a single visit. However, the comparative utility of single versus sequential risk factor measurements for stroke prediction is unclear. Risk factors were recorded on three separate visits on 13,753 individuals in the prospective China Kadoorie Biobank. All participants were stroke-free at baseline (2004-2008), first resurvey (2008), and second resurvey (2013-2014), and were followed-up for incident cases of first stroke in the 3 years following the second resurvey. To reflect the models currently used in clinical practice, sex-specific Cox models were developed to estimate 3-year risks of stroke using single measurements recorded at second resurvey and were retrospectively applied to risk factor data from previous visits. Temporal trends in the Cox-generated risk estimates from 2004 to 2014 were analyzed using linear mixed effects models. To assess the value of more flexible machine learning approaches and the incorporation of longitudinal data, we developed gradient boosted tree (GBT) models for 3-year prediction of stroke using both single measurements and sequential measurements of risk factor inputs. Overall, Cox-generated estimates for 3-year stroke risk increased by 0.3% per annum in men and 0.2% per annum in women, but varied substantially between individuals. The risk estimates at second resurvey were highly correlated with the annual increase of risk for each individual (men: r = 0.91, women: r = 0.89), and performance of the longitudinal GBT models was comparable with both Cox and GBT models that considered measurements from only a single visit (AUCs: 0.779-0.811 in men, 0.724-0.756 in women). These results provide support for current clinical guidelines, which recommend using risk factor measurements recorded at a single visit for stroke prediction.

8.
Environ Res ; 204(Pt A): 111995, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34492278

RESUMO

Due to the potential hazard of perfluorooctanoic acid (PFOA), hexafluoropropylene oxide dimer acid (HFPO-DA, GenX) has become a typical alternative since 2009. However, GenX has recently been reported to have equal or even greater toxicity and bioaccumulation than PFOA. Considering the suitability of alternatives, it is quite essential to study and compare the degradation degree between PFOA and GenX in water. Therefore, in the present study, a comprehensive degradation comparison between them via electrooxidation with a titanium suboxide membrane anode was conducted. The degradation rate decreased throughout for PFOA, while it first increased and then decreased for GenX when the permeate flux increased from 17.3 L to 100.3 L m-2·h-1. The different responses of PFOA and GenX to flux might be attributed to their different solubilities. In addition, the higher kobs of PFOA demonstrated that it had a better degradability than GenX by 2.4-fold in a mixed solution. The fluorinated byproduct perfluoropropanoic acid (PFPrA) was detected as a GenX intermediate, suggesting that ether bridge splitting was needed for GenX electrooxidation. This study provides a reference for assessing the degradability of GenX and PFOA and indicates that it is worth reconsidering whether GenX is a suitable alternative for PFOA from the point of view of environmental protection.

9.
Bioresour Technol ; 343: 126045, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34592460

RESUMO

Recently, phosphorus recovery as vivianite from sludge digestion system has attracted increasing attention because of its high recovery efficiency and economic value. However, the potential impact of vivianite on anaerobic digestion of waste activated sludge remains largely unknown. This study therefore aims to provide such support. Experimental results revealed that the maximal methane yield decreased from 103.55 to 76.55 mL/g volatile solids, with the vivianite level increasing from 0 to 500 mg P/L. Mechanism explorations showed that vivianite caused more substrates remaining in tightly-bound extracellular polymeric substances, and thus suppressed sludge solubilization. In addition, it was observed that hydrolysis, acidiogenesis, acetogenesis and methanogenesis bio-processes were all inhibited by vivianite. Microbial analysis revealed that vivianite significantly decreased the relative abundances of hydrolytic microbes, acidogens and methanogens. Further investigation showed that vivianite benefited sludge agglomeration and can enhance the mass transfer resistance of anaerobic digestion, further supporting the inhibitions on anaerobic digestion.

10.
G3 (Bethesda) ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515796

RESUMO

Aegilops tauschii is the donor of the D subgenome of hexaploid wheat and an important genetic resource. The reference-quality genome sequence Aet v4.0 for Ae. tauschii acc. AL8/78 was therefore an important milestone for wheat biology and breeding. Further advances in sequencing acc. AL8/78 and release of the Aet v5.0 sequence assembly are reported here. Two new optical maps were constructed and used in the revision of pseudomolecules. Gaps were closed with Pacific Biosciences long-read contigs, decreasing the gap number by 38,899. Transposable elements and protein-coding genes were reannotated. The number of annotated high-confidence genes was reduced from 39,635 in Aet v4.0 to 32,885 in Aet v5.0. A total of 2,245 biologically important genes, including those affecting plant phenology, grain quality, and tolerance of abiotic stresses in wheat was manually annotated and disease-resistance genes were annotated by a dedicated pipeline. Disease-resistance genes encoding nucleotide-binding site domains, receptor-like protein kinases, and receptor-like proteins were preferentially located in distal chromosome regions, whereas those encoding transmembrane coiled-coil proteins were dispersed more evenly along the chromosomes. Discovery, annotation, and expression analyses of microRNA (miRNA) precursors, mature miRNAs, and phasiRNAs are reported, including miRNA target genes. Other small RNAs, such as hc-siRNAs and tRFs, were characterized. These advances enhance the utility of the Ae. tauschii genome sequence for wheat genetics, biotechnology, and breeding.

11.
Water Sci Technol ; 84(3): 596-608, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388121

RESUMO

The iron oxychloride/pillared montmorillonite (FeOCl/MMT) catalyst was prepared by wet impregnation method and solid melting method. Various characterization techniques were used to analyze the microscopic morphology and structure of a series of catalysts. Moreover, the catalysts were used to treat magenta-simulated dye wastewater through catalytic wet peroxide oxidation (CWPO) degradation. The magenta removal rate and chemical oxygen demand (COD) removal rate of the magenta-simulated dye wastewater were used to evaluate the catalytic performance of the catalyst, and the optimal catalyst preparation conditions were selected. The results showed that the solid melting method was more favorable to the preparation of the catalyst, and the COD removal rate of wastewater can reach 70.8% when the FeOCl load was 3%. Moreover, 96.2% of the magenta in the solution was removed. The COD removal rate of the magenta wastewater decreased by only 12.4% after the catalyst was repeatedly used six times, indicating that the catalyst has good activity and stability. The Fermi equation can simulate the reaction process of the catalyst treating magenta wastewater at high temperature.


Assuntos
Peróxidos , Águas Residuárias , Bentonita , Catálise , Peróxido de Hidrogênio , Oxirredução , Corantes de Rosanilina
12.
Sci Total Environ ; 800: 149392, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34388643

RESUMO

Polyoxometalates (POMs), a versatile and environmentally-friendly inorganic material, have been extensively studied and applied in chemical catalytic oxidation and biological nutrients removal processes. However, little is known about effects of POMs pretreatment on anaerobic sludge fermentation. This study thereby filled such knowledge gap and provided insights into the underlying mechanisms. Results demonstrated the maximal short-chain fatty acids (SCFAs) production increased by 6.18 times with POMs rising from 0 to 0.05 g/g TSS. Mechanistic investigations revealed that the oxidation stress of POMs as well as reactive oxygen species (ROS) activated by POMs were responsible for the disintegration of waste activated sludge (WAS). More importantly, POMs pretreatment improved the biodegradability of organics released, providing more biodegradable substrates for SCFAs generation. Furthermore, the inhibition of POMs to SCFAs producers was less severe than that to SCFAs consumers, leading to SCFAs accumulation. Microbial community analysis exhibited that increased the population of hydrolysis (i.e., Longilinea) and SCFAs generation microbes (i.e., Acinetobacter and Fusibacter). Further evaluation showed that the POMs-based technology is economically and environmentally attractive for the pretreatment of WAS. Finally, a "closed-loop" concept of the reutilization of renewable POMs may provide an important implication of WAS management in the future.

13.
Front Public Health ; 9: 514687, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422735

RESUMO

Background: The literature shows that migration characteristics are a potential pathway through which migration can influence basic healthcare service utilization. The goal of the study was to explore the effect of migration characteristics on the utilization of basic public health services for internal elderly migrants in China and to identify the pathways that might promote their utilization of basic public health services. Methods: We studied 1,544 internal elderly migrants. The utilization of basic public health services was determined through participation in free health checkups organized by community health service institutions in the past year. Migration characteristics were represented by years of residence and reasons for migration. Other variables included demographic characteristics and social factors, e.g., the number of local friends and exercise time per day were measured to represent social contacts. Multivariate binary logistic regression was employed to explore the association of the variables with the likelihood of using community health services. Results: A total of 55.6% of respondents were men, and the mean age was 66.34 years (SD 5.94). A low level of education was observed. A total of 59.9% of migrants had been residents for over 10 years, and the main reason for migrating was related to family. Of these migrants, 12.9% had no local friends. Furthermore, 5.2% did not exercise every day. Social contacts were complete mediators of the impact of migration characteristics on the utilization of primary healthcare. Conclusion: Our study highlighted the mediating role of social factors in the relationship between migration characteristics and the utilization of basic public health services among Chinese internal elderly migrants. The findings supported the need to increase the opportunities for social contacts between local elderly individuals and internal elderly migrants.


Assuntos
Migrantes , Idoso , China , Serviços de Saúde Comunitária , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Atenção Primária à Saúde , Estados Unidos
14.
Nat Commun ; 12(1): 4804, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376671

RESUMO

Plants respond to warm temperature by increased elongation growth of organs to enhance cooling capacity. Phytohormones, such as auxin and brassinosteroids, regulate this growth process. However, our view on the players involved in warm temperature-mediated growth remains fragmentary. Here, we show that warm temperature leads to an increased expression of JOXs and ST2A, genes controlling jasmonate catabolism. This leads to an elevated 12HSO4-JA level and consequently to a reduced level of bioactive jasmonates. Ultimately this results in more JAZ proteins, which facilitates plant growth under warm temperature conditions. Taken together, understanding the conserved role of jasmonate signalling during thermomorphogenesis contributes to ensuring food security under a changing climate.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Ciclopentanos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Temperatura , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais
15.
Healthc Technol Lett ; 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34221413

RESUMO

COVID-19 is a major, urgent, and ongoing threat to global health. Globally more than 24 million have been infected and the disease has claimed more than a million lives as of November 2020. Predicting which patients will need respiratory support is important to guiding individual patient treatment and also to ensuring sufficient resources are available. The ability of six common Early Warning Scores (EWS) to identify respiratory deterioration defined as the need for advanced respiratory support (high-flow nasal oxygen, continuous positive airways pressure, non-invasive ventilation, intubation) within a prediction window of 24 h is evaluated. It is shown that these scores perform sub-optimally at this specific task. Therefore, an alternative EWS based on the Gradient Boosting Trees (GBT) algorithm is developed that is able to predict deterioration within the next 24 h with high AUROC 94% and an accuracy, sensitivity, and specificity of 70%, 96%, 70%, respectively. The GBT model outperformed the best EWS (LDTEWS:NEWS), increasing the AUROC by 14%. Our GBT model makes the prediction based on the current and baseline measures of routinely available vital signs and blood tests.

16.
Front Immunol ; 12: 659193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34326834

RESUMO

Sepsis is a heterogeneous syndrome induced by infection and results in high mortality. Even though more than 100 biomarkers for sepsis prognosis were evaluated, prediction of patient outcomes in sepsis continues to be driven by clinical signs because of unsatisfactory specificity and sensitivity of these biomarkers. This study aimed to elucidate the key candidate genes involved in sepsis response and explore their downstream effects based on weighted gene co-expression network analysis (WGCNA). The dataset GSE63042 with sepsis outcome information was obtained from the Gene Expression Omnibus (GEO) database and then consensus WGCNA was conducted. We identified the hub gene SDF4 (stromal cell derived factor 4) from the M6 module, which was significantly associated with mortality. Subsequently, two datasets (GSE54514 and E-MTAB-4421) and cohort validation (n=89) were performed. Logistic regression analysis was used to build a prediction model and the combined score resulting in a satisfactory prognosis value (area under the ROC curve=0.908). The model was subsequently tested by another sepsis cohort (n=70, ROC= 0.925). We next demonstrated that endoplasmic reticulum (ER) stress tended to be more severe in patients PBMCs with negative outcomes compared to those with positive outcomes and SDF4 was related to this phenomenon. In addition, our results indicated that adenovirus-mediated Sdf4 overexpression attenuated ER stress in cecal ligation and puncture (CLP) mice lung. In summary, our study indicates that incorporation of SDF4 can improve clinical parameters predictive value for the prognosis of sepsis, and decreased expression levels of SDF4 contributes to excessive ER stress, which is associated with worsened outcomes, whereas overexpression of SDF4 attenuated such activation.


Assuntos
Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Glicoproteínas/metabolismo , Sepse/metabolismo , Sepse/mortalidade , Proteínas de Ligação ao Cálcio/sangue , Proteínas de Ligação ao Cálcio/genética , Biologia Computacional , Bases de Dados Genéticas , Suscetibilidade a Doenças , Imunofluorescência , Perfilação da Expressão Gênica , Glicoproteínas/sangue , Glicoproteínas/genética , Humanos , Imuno-Histoquímica , Prognóstico , Curva ROC , Sepse/diagnóstico , Sepse/etiologia , Transcriptoma
17.
Mol Plant Pathol ; 22(10): 1239-1255, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34288333

RESUMO

Fusarium oxysporum is the causal agent of the devastating Fusarium wilt by invading and colonizing the vascular system in various plants, resulting in substantial economic losses worldwide. Target of rapamycin (TOR) is a central regulator that controls intracellular metabolism, cell growth, and stress responses in eukaryotes, but little is known about TOR signalling in F. oxysporum. In this study, we identified conserved FoTOR signalling pathway components including FoTORC1 and FoTORC2. Pharmacological assays showed that F. oxysporum is hypersensitive to rapamycin in the presence of FoFKBP12 while the deletion mutant strain ΔFofkbp12 is insensitive to rapamycin. Transcriptomic data indicated that FoTOR signalling controls multiple metabolic processes including ribosome biogenesis and cell wall-degrading enzymes (CWDEs). Genetic analysis revealed that FoTOR1 interacting protein 4 (FoTIP4) acts as a new component of FoTOR signalling to regulate hyphal growth and pathogenicity of F. oxysporum. Importantly, transcript levels of genes associated with ribosome biogenesis and CWDEs were dramatically downregulated in the ΔFotip4 mutant strain. Electrophoretic mobility shift assays showed that FoTIP4 can bind to the promoters of ribosome biogenesis- and CWDE-related genes to positively regulate the expression of these genes. These results suggest that FoTOR signalling plays central roles in regulating hyphal growth and pathogenicity of F. oxysporum and provide new insights into FoTOR1 as a target for controlling and preventing Fusarium wilt in plants.

18.
Lab Invest ; 101(10): 1318-1326, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34230646

RESUMO

In the myocardial infarction microenvironment, the effect of macrophages on the function of bone marrow mesenchymal stem cells (BMSCs) is unclear. In this study, we investigated the role of hypoxia/serum deprivation (H/SD)-induced M1-type macrophage-derived exosomes on BMSC viability, migration, and apoptosis. We found that H/SD reduced BMSC viability and migration, increased BMSC apoptosis, and induced macrophage polarization toward the M1 phenotype. BMSCs were cultured by the supernatant of H/SD-induced THP-1 cells (M1-type macrophages) with or without exosome inhibitor treatment. The results show that BMSC apoptosis is increased in the H/SD-induced THP-1 cell supernatant group and is decreased by GM4869 treatment, indicating that M1-type macrophages induce BMSC apoptosis through exosomes. In addition, we confirm that miR-222 plays an important role in promoting BMSC apoptosis by targeting B-cell lymphoma (Bcl)-2. M1-type macrophage-derived exosomes significantly decrease BMSC viability and migration and increase BMSC apoptosis, and these effects are partly abolished by a miR-222 inhibitor. Our findings suggest that under H/SD conditions, exosomes derived from M1-type macrophages can induce BMSC apoptosis by delivering miR-222 to BMSCs.


Assuntos
Apoptose/fisiologia , Exossomos , Macrófagos , Células-Tronco Mesenquimais , MicroRNAs/metabolismo , Hipóxia Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
19.
Angew Chem Int Ed Engl ; 60(38): 20970-20976, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34278678

RESUMO

Halide hybrid perovskites are attracting considerable attention as highly promising candidates for directly sensing X-ray radiation, but it is challenging to realize passive X-ray detection without an external power supply. However, the bulk photovoltaic effect (BPVE) in ferroelectrics promotes the independent separation of photoexcited carriers. Herein, by dimensionality reconstruction of a pure-two-dimensional (P-2D) monolayered perovskite (CH3 OC3 H9 N)2 PbBr4 , we obtained a quasi-two-dimensional (Q-2D) ferroelectric (CH3 OC3 H9 N)2 CsPb2 Br7 . Converting P-2D into Q-2D perovskite stimulates a significant BPVE associated with robust ferroelectricity, as well as an enhanced mobility lifetime product. These features show the potential of the first passive X-ray detector based on ferroelectrics with an impressive sensitivity up to 410 µC Gy-1 cm-2 at zero bias, which is even superior to the value of the state-of-the-art α-Se detector operated at relatively high bias.

20.
Nat Commun ; 12(1): 4221, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244504

RESUMO

Deep learning algorithms trained on instances that violate the assumption of being independent and identically distributed (i.i.d.) are known to experience destructive interference, a phenomenon characterized by a degradation in performance. Such a violation, however, is ubiquitous in clinical settings where data are streamed temporally from different clinical sites and from a multitude of physiological sensors. To mitigate this interference, we propose a continual learning strategy, entitled CLOPS, that employs a replay buffer. To guide the storage of instances into the buffer, we propose end-to-end trainable parameters, termed task-instance parameters, that quantify the difficulty with which data points are classified by a deep-learning system. We validate the interpretation of these parameters via clinical domain knowledge. To replay instances from the buffer, we exploit uncertainty-based acquisition functions. In three of the four continual learning scenarios, reflecting transitions across diseases, time, data modalities, and healthcare institutions, we show that CLOPS outperforms the state-of-the-art methods, GEM1 and MIR2. We also conduct extensive ablation studies to demonstrate the necessity of the various components of our proposed strategy. Our framework has the potential to pave the way for diagnostic systems that remain robust over time.


Assuntos
Arritmias Cardíacas/diagnóstico , Tomada de Decisão Clínica/métodos , Sistemas de Apoio a Decisões Clínicas , Aprendizado Profundo , Conjuntos de Dados como Assunto , Eletrocardiografia , Humanos , Modelos Cardiovasculares , Curva ROC , Estações do Ano , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...