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1.
Biomaterials ; 278: 121162, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34628191

RESUMO

Osseointegration is a sophisticated bone and implant healing process comprising of initial hematoma formation, immediate osteoimmunomodulation, angiogenesis, and osteogenesis. To fulfill rapid and satisfying osseointegration, this study developed a biomimetic implant coating that could confer the intraosseous implants a systematical regulation of the participatory processes. Herein, we shaped dissimilar nano-scale (NS) to form highly biomimetic structures of natural extracellular matrix (ECM) of the host bone and bone healing hematoma with micro/nano-scale (MNS) titania fiber-like network on the surface of titanium (Ti) implants. In vitro experiments revealed that the MNS not only facilitated osteogenic and angiogenic differentiation of bone marrow stromal cells (BMSCs) and endothelial cells, respectively, but also suppressed M1 macrophages (MΦs), whereas, stimulated pro-healing M2 phenotype. Notably, BMSCs on MNS surfaces enabled a significant immunomodulatory effect on MΦs resulting in the downregulation of inflammation-related cell signaling pathways. The favorable osteoimmune microenvironment manipulated by MNS further facilitated osteo-/angio-genesis via the crosstalk of multi-signaling pathways. In vivo evaluation mirrored the aforementioned results, and depicted that MNS induced ameliorative osseointegration when compared with the NS as well as the pristine Ti implant. The study demonstrated the modulatory effect of the multifaceted biomimetic structure on spatiotemporal regulation of the participatory processes during osseointegration.

2.
Sci Total Environ ; 794: 148637, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323767

RESUMO

It has been reported that air quality models largely underestimate PM2.5 concentrations during severe pollution events in China. In this study, the Models-3 Community Multi-scale Air Quality model (CMAQ) was employed to simulate PM2.5 concentrations in May-June (non-heating period) and in November-December (heating period) of 2013 in northern China, with a particular focus on determining the causes of the underestimation. Modeling results reproduced the mass concentrations of PM2.5 in approximately 50% of the non-heating and heating periods in Qingdao (referred to as the good periods), while the model performance was unsatisfactory during the remaining periods (the poor periods). In this respect, the overprediction of inorganic salts and the underprediction of organic matter in PM2.5 canceled each other out and resulted in a good simulation of PM2.5 concentrations during the good periods, whereas during poor periods, the bias of the planetary boundary layer height, wind direction, precipitation, and other factors caused inconsistencies between the simulated and observed PM2.5 concentrations. Sensitivity studies showed that the underestimation of primarily emitted particles from local emissions was likely the main cause of PM2.5 underpredictions during heavy haze days. Furthermore, our results implied that the assumption of the conditions of the gas-aerosol thermodynamic equilibria in the air quality model likely results in an overprediction of secondary PM2.5 inorganic salts (SO42- + NO3- + NH4+) during clear days. In contrast, during heavy pollution or heavy haze days, high concentrations of air pollutants theoretically rapidly leads to gas/particle chemical equilibrium and no overprediction of SO42-, NO3-, and NH4+ concentrations. Nevertheless, the underestimation of primarily emitted particles from local sources during heavy haze days is yet to be explained and needs further investigation.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
3.
Brain Tumor Pathol ; 38(3): 189-200, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34231121

RESUMO

Current conventional treatment strategies for glioblastoma (GBM) have limited efficacy due to the rapid development of resistance to temozolomide (TMZ). It is particularly urgent to develop novel therapeutic strategies that can overcome TMZ resistance and provide patients with better prognoses. Here, a TMZ-resistant GBM cell strain and a mouse model of TMZ resistance are established as valuable tools to explore novel therapeutic strategies against TMZ resistance. Experimentally, p38MAPK inhibitor reduces the accumulation of F4/80+/CD11b+ macrophages/microglia in glioma and prolongs the survivals of glioma-bearing mice. Glioma-associated macrophages/microglia have a significanct expression of PD-L1. p38MAPK inhibitor in combination with PD-L1 antibody can effectively prolongs the survivals of TMZ-resistant GBM-bearing hosts, and differentially reduces the accumulation of circulating monocytes-derived tumor-associated macrophages and PD-L1 abundances of resident glioma-associated microglia. This combination therapy could be a treatment option for patients at the recurrence or chronic TMZ maintenance stages. A clinical study to confirm the safety and effectiveness of this combination therapy is warranted.

4.
Nat Commun ; 12(1): 4413, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285210

RESUMO

Enhanced neovasculogenesis, especially vasculogenic mimicry (VM), contributes to the development of triple-negative breast cancer (TNBC). Breast tumor-initiating cells (BTICs) are involved in forming VM; however, the specific VM-forming BTIC population and the regulatory mechanisms remain undefined. We find that tumor endothelial marker 8 (TEM8) is abundantly expressed in TNBC and serves as a marker for VM-forming BTICs. Mechanistically, TEM8 increases active RhoC level and induces ROCK1-mediated phosphorylation of SMAD5, in a cascade essential for promoting stemness and VM capacity of breast cancer cells. ASB10, an estrogen receptor ERα trans-activated E3 ligase, ubiquitylates TEM8 for degradation, and its deficiency in TNBC resulted in a high homeostatic level of TEM8. In this work, we identify TEM8 as a functional marker for VM-forming BTICs in TNBC, providing a target for the development of effective therapies against TNBC targeting both BTIC self-renewal and neovasculogenesis simultaneously.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas dos Microfilamentos/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica/patologia , Receptores de Superfície Celular/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Mama/patologia , Mama/cirurgia , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Linhagem Celular Tumoral , Autorrenovação Celular/efeitos dos fármacos , Feminino , Humanos , Mastectomia , Camundongos , Proteínas dos Microfilamentos/antagonistas & inibidores , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Receptores de Superfície Celular/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/irrigação sanguínea , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
BMC Plant Biol ; 21(1): 325, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229602

RESUMO

BACKGROUND: Plant phylogeographic studies of species in subtropical China have mainly focused on rare and endangered species, whereas few studies have been conducted on taxa with relatively wide distribution, especially polyploid species. We investigated the cytotype and haplotype distribution pattern of the Actinidia chinensis complex, a widespread geographically woody liana with variable ploidy in subtropical China comprising two varieties, with three chloroplast fragments DNA (ndhF-rpl132, rps16-trnQ and trnE-trnT). Macroevolutionary, microevolutionary and niche modeling tools were also combined to disentangle the origin and the demographic history of the species or cytotypes. RESULTS: The ploidy levels of 3338 individuals from 128 populations sampled throughout the species distribution range were estimated with flow cytometry. The widespread cytotypes were diploids followed by tetraploids and hexaploids, whereas triploids and octoploids occurred in a few populations. Thirty-one chloroplast haplotypes were detected. The genetic diversity and genetic structure were found to be high between varieties (or ploidy races) chinensis and deliciosa. Our results revealed that these two varieties inhabit significantly different climatic niche spaces. Ecological niche models (ENMs) indicate that all varieties' ranges contracted during the Last Inter Glacial (LIG), and expanded eastward or northward during the Last Glacial Maximum (LGM). CONCLUSIONS: Pliocene and Plio-Pleistocene climatic fluctuations and vicariance appear to have played key roles in shaping current population structure and historical demography in the A. chinensis complex. The polyploidization process also appears to have played an important role in the historical demography of the complex through improving their adaptability to environmental changes.


Assuntos
Actinidia/classificação , Actinidia/citologia , Cloroplastos/classificação , Filogeografia , Teorema de Bayes , China , DNA de Cloroplastos/genética , Ecossistema , Variação Genética , Genética Populacional , Haplótipos/genética , Método de Monte Carlo , Ploidias
6.
Cell Res ; 31(8): 836-846, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34135479

RESUMO

Severe COVID-19 disease caused by SARS-CoV-2 is frequently accompanied by dysfunction of the lungs and extrapulmonary organs. However, the organotropism of SARS-CoV-2 and the port of virus entry for systemic dissemination remain largely unknown. We profiled 26 COVID-19 autopsy cases from four cohorts in Wuhan, China, and determined the systemic distribution of SARS-CoV-2. SARS-CoV-2 was detected in the lungs and multiple extrapulmonary organs of critically ill COVID-19 patients up to 67 days after symptom onset. Based on organotropism and pathological features of the patients, COVID-19 was divided into viral intrapulmonary and systemic subtypes. In patients with systemic viral distribution, SARS-CoV-2 was detected in monocytes, macrophages, and vascular endothelia at blood-air barrier, blood-testis barrier, and filtration barrier. Critically ill patients with long disease duration showed decreased pulmonary cell proliferation, reduced viral RNA, and marked fibrosis in the lungs. Permanent SARS-CoV-2 presence and tissue injuries in the lungs and extrapulmonary organs suggest direct viral invasion as a mechanism of pathogenicity in critically ill patients. SARS-CoV-2 may hijack monocytes, macrophages, and vascular endothelia at physiological barriers as the ports of entry for systemic dissemination. Our study thus delineates systemic pathological features of SARS-CoV-2 infection, which sheds light on the development of novel COVID-19 treatment.


Assuntos
COVID-19/patologia , Pulmão/virologia , SARS-CoV-2/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Autopsia , COVID-19/virologia , China , Estudos de Coortes , Estado Terminal , Feminino , Fibrose , Hospitalização , Humanos , Rim/patologia , Rim/virologia , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/virologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/metabolismo , SARS-CoV-2/genética , Baço/patologia , Baço/virologia , Traqueia/patologia , Traqueia/virologia
7.
J Mater Chem B ; 9(18): 3800-3807, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33899897

RESUMO

Osteogenesis and angiogenesis are both important for implant osseointegration, which can be tailored by immunomodulation of macrophages. Zn, a novel biodegradable material, can modulate macrophage functions in its ionic form. However, whether macrophage-derived exosomes, novel carriers of intracellular communication, participate in the process is still unclear. The present work shows that Zn ions in the concentration range of 0-100 µM have no significant influence on macrophage viability, proliferation, morphology, and secretion amount of exosomes, but generally downregulate the gene expression of both M1 and M2 markers. The exosomes can be ingested continuously by osteoblasts and endothelial cells. The osteoblasts show the highest alkaline phosphatase activity after ingesting the exosomes derived from macrophages upon 4 µM Zn ion stimulation. In contrast, the endothelial cells migrate the furthest distance after ingesting the exosomes upon 20 µM Zn ion stimulation. These results indicate that Zn ions may vary the composition of macrophage-derived exosomes, which in turn affects the osteogenesis and angiogenesis. These findings are meaningful for the surface design of immunomodulatory biomaterials from the perspective of macrophage-derived exosomes.


Assuntos
Movimento Celular/efeitos dos fármacos , Exossomos/metabolismo , Regulação para Cima/efeitos dos fármacos , Zinco/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Exossomos/efeitos dos fármacos , Exossomos/transplante , Íons/química , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Microscopia de Fluorescência , Osteoblastos/citologia , Osteoblastos/metabolismo , Células RAW 264.7 , Zinco/química
8.
Cell Death Differ ; 28(9): 2765-2777, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33879858

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is highly contagious and causes lymphocytopenia, but the underlying mechanisms are poorly understood. We demonstrate here that heterotypic cell-in-cell structures with lymphocytes inside multinucleate syncytia are prevalent in the lung tissues of coronavirus disease 2019 (COVID-19) patients. These unique cellular structures are a direct result of SARS-CoV-2 infection, as the expression of the SARS-CoV-2 spike glycoprotein is sufficient to induce a rapid (~45.1 nm/s) membrane fusion to produce syncytium, which could readily internalize multiple lines of lymphocytes to form typical cell-in-cell structures, remarkably leading to the death of internalized cells. This membrane fusion is dictated by a bi-arginine motif within the polybasic S1/S2 cleavage site, which is frequently present in the surface glycoprotein of most highly contagious viruses. Moreover, candidate anti-viral drugs could efficiently inhibit spike glycoprotein processing, membrane fusion, and cell-in-cell formation. Together, we delineate a molecular and cellular rationale for SARS-CoV-2 pathogenesis and identify novel targets for COVID-19 therapy.


Assuntos
COVID-19/virologia , Células Gigantes/virologia , Linfócitos/virologia , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/patologia , Linhagem Celular , Linhagem Celular Tumoral , Células Gigantes/patologia , Células HEK293 , Células HeLa , Humanos , Células Jurkat , Células K562 , Linfócitos/patologia , Internalização do Vírus , Replicação Viral/genética
9.
Colloids Surf B Biointerfaces ; 203: 111742, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33838581

RESUMO

Angiogenesis is critical for tissue repair and regeneration, including implant osseointegration. It is well known that macrophages exert immunomodulatory functions in angiogenesis. However, whether macrophage-derived exosomes participate in the process is still unclear. Cobalt (Co) ions are frequently used as implant additives to mimic hypoxic microenvironment, which can induce angiogenesis through stabilizing hypoxia inducible factor-1α (HIF-1α) of macrophages and endothelial cells (ECs). The present work attempts to investigate whether exosomes derived from macrophages upon Co ion stimulation can mediate angiogenesis and the possible mechanism. The results show that the exosomes promote endothelial migration and angiogenesis in vitro and in vivo, particularly when Co ion concentration is 200 µM. Further studies reveal that the exosomes upregulating nitric oxide (NO), vascular endothelial growth factor (VEGF), and integrin ß1 expression may be the underlying mechanism of the observations. Our findings provide new insights for Co ion mediated macrophage-EC communication and surface design of biomaterials from the perspective of pro-angiogenesis.


Assuntos
Exossomos , Cobalto/farmacologia , Células Endoteliais , Subunidade alfa do Fator 1 Induzível por Hipóxia , Íons , Macrófagos , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular
10.
Mater Sci Eng C Mater Biol Appl ; 123: 111981, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812609

RESUMO

Copper, a frequently used additive of implant materials, can alter macrophage phenotype thus directing the fate of the implants. Exosomes, secreted by mammalian cells, can target to recipient cells and mediate their functions. However, whether exosomes derived from macrophages upon copper ion stimulation can modulate angiogenesis, a key index for implant osseointegration, is still unclear. Herein, the influence of copper ions on macrophage-derived exosome secretion, ingestion behavior by endothelial cells, and angiogenic-induction ability is investigated. The results show copper ions (0-100 µM) have little influence on the secretion of macrophage-derived exosomes. Endothelial cells can uptake the exosomes from all the groups in a time-dependent manner. The exosomes have little influence on endothelial adhesion and proliferation, but can upregulate angiogenic ability of endothelial cells in vitro and in vivo, which may be related to trafficking of integrin ß1. The results provide insight into the effect of copper ions on immunomodulatory mechanism of macrophages, which is important for implant design from the perspective of material compositions.


Assuntos
Exossomos , Animais , Cobre/farmacologia , Células Endoteliais , Íons , Macrófagos
11.
Mater Sci Eng C Mater Biol Appl ; 123: 112007, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812627

RESUMO

Stent implantation has become one of the most widely used methods for the treatment of cardiovascular diseases. However, endothelial dysfunction and abnormal inflammatory response following implantation may lead to delayed re-endothelialization, resulting in vascular restenosis and stent thrombus. To address the concerns, we constructed nanospindles composed of TiO2 and Ti4Ni2O through hydrothermal treatment of amorphous Ni-Ti-O nanopores anodically grown on NiTi alloy. The results show the treatment can significantly improve hydrophilicity and reduce Ni ion release, essentially independent of hydrothermal duration. The nanospindle surfaces not only promote the expression of endothelial functionality but also activate macrophages to induce a favorable immune response, downregulate pro-inflammatory M1 markers and upregulate pro-healing M2 markers. Moreover, nitric oxide (NO) synthesis, VEGF secretion, and migration of endothelial cells are enhanced after cultured in macrophage conditioned medium. The nanospindles thus are promising as vascular stent coatings to promote re-endothelization.


Assuntos
Ligas , Células Endoteliais , Imunidade , Níquel , Propriedades de Superfície , Titânio
12.
Huan Jing Ke Xue ; 42(5): 2133-2142, 2021 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-33884782

RESUMO

Atmospheric particle number size distributions were measured by a wide-range particle size spectrometer and a scanning mobility particle size spectrometer in the summertime and wintertime in the coastal area of Qingdao (China). The inorganic and organic gaseous precursors and particulate chemical composition were measured to characterize new particle formation (NPF) events by combining meteorological parameters and backward trajectories. In summer, the occurrence frequency of NPF events was 18% lower. However, the atmospheric particle number concentration increased by approximately 1-4 times during the NPF events compared with those without NPF. The apparent formation rates and growth rates were (5.2±4.3) cm-3·s-1 and (6.5±2.2) nm·h-1, respectively, except for a special NPF event on July 20. The correlation analysis results implied that biogenic volatile organic compounds (BVOCs) seemingly favor NPF, and the reverse is true for anthropogenic volatile organic compounds (AVOCs). The occurrence frequency of NPF events of 27% in winter was clearly higher than that in summer. The apparent formation rates and growth rates, i.e., (3.3±3.1) cm-3·s-1 and (5.3±3.3) nm·h-1, decreased, although the decreases were not significant (P>0.05). The correlation analyses implied that AVOCs favored NPF. However, BVOCs had no correlation with NPF. For the cases in which new particles could grow to CCN sizes (>50 nm), the particle growth characteristics showed significant seasonal differences, i.e., in summer, new particles could grow to CCN sizes via photochemical reactions, whereas in winter, second-stage growth driven by the formation of nitrate aerosols was needed to grow new particles to CCN sizes.

14.
Sci Total Environ ; 769: 145488, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736263

RESUMO

With the rapid expansion of maritime traffic, increases in air emissions from shipping have exacerbated numerous environmental issues, including air pollution and climate change. However, the effects of such emissions on marine biogeochemistry remain poorly understood. Here, we collected ship-emitted particles (SEPs) from the stack of a heavy-oil-powered vessel using an onboard emission test system and investigated the impact of SEPs on phytoplankton growth over the northwest Pacific Ocean (NWPO). In SEP microcosm experiments conducted in oceanic zones with different trophic statuses, the phytoplankton response, as indicated by chlorophyll a (Chl a), has been shown to increase with the proportion of SEP-derived nitrogen (N) relative to N stocks (PSN) in baseline seawater, suggesting that SEPs generally promote phytoplankton growth via N fertilisation. Simulations using an air quality model combined with a ship emission inventory further showed that oxidised N (NOx) emissions from shipping contributed ~43% of the atmospheric N deposition flux in the NWPO. Air emissions from shipping (e.g. NOx and sulphur dioxide) also indirectly enhanced the deposition of reduced N that existed in the atmosphere, constituting ~15% of the atmospheric N deposition flux. These results suggest that the impact of airborne ship emissions on atmospheric N deposition is comparable to that of land-based emissions in the NWPO. Based on the ship-induced PSN in surface seawater calculated by modeling results and World Ocean Atlas 2013 nutrient dataset, and the well-established quantitative relationship between Chl a and PSN obtained from microcosm experiments, we found a noticeable change in surface Chl a concentrations due to N deposition derived from marine traffic in the NWPO, particularly in the coastal waters of the Yellow Sea and open oceans. This work attempts to establish a direct link between marine productivity and air emissions from shipping.


Assuntos
Fitoplâncton , Navios , Clorofila A , Oceanos e Mares , Oceano Pacífico
15.
J Environ Sci (China) ; 103: 1-11, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33743892

RESUMO

To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM2.5 data have been collected across Canada through the National Air Pollution Surveillance network in the past decade. 24-hr time integrated PM2.5 collected at seven urban and two rural sites during 2010-2016 were analyzed to characterize geographical and seasonal patterns and associated potential causes. Site-specific seven-year mean gravimetric PM2.5 mass concentrations ranged from 5.7 to 9.6 µg/m3. Seven-year mean concentrations of SO42-, NO3-, NH4+, organic carbon (OC), and elemental carbon (EC) were in the range of 0.68 to 1.6, 0.21 to 1.5, 0.27 to 0.71, 1.1 to 1.9, and 0.37 to 0.71 µg /m3, accounting for 10.8%-18.1%, 3.7%-16.7%, 4.7%-7.4%, 18.4%-21.0%, and 6.4%-10.6%, respectively, of gravimetric PM2.5 mass. PM2.5 and its five major chemical components showed higher concentrations in southeastern Canada and lower values in Atlantic Canada, with the seven-year mean ratios between the two regions being on the order of 1.7 for PM2.5 and 1.8-7.1 for its chemical components. When comparing the concentrations between urban and rural sites within the same region, those of SO42- and NH4+ were comparable, while those of NO3-, OC, and EC were around 20%, 40%-50%, and 70%-80%, respectively, higher at urban than rural sites, indicating the regional scale impacts of SO42- and NH4+ and effects of local sources on OC and EC. Monthly variations generally showed summertime peaks for SO42- and wintertime peaks for NO3-, but those of NH4+, OC, and EC exhibited different seasonality at different locations.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Canadá , Carbono/análise , China , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano
16.
ACS Biomater Sci Eng ; 7(4): 1438-1449, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33691399

RESUMO

Microbial infection and the limitation of tissue regeneration are main obstacles to chronic wound healing. Herein, a biofunctional hydrogel is prepared to simultaneously kill bacteria efficiently and promote would healing. First, a rose bengal/polypyrrole hybrid poly(vinyl alcohol) hydrogel (RB/PPy PVA HD) is synthesized and its antibacterial property is investigated under coirradiation of 550 nm visible light and 808 near-infrared light. The hydrogel exhibits excellent antibacterial activity within 10 min below 45 °C in vitro due to the synergistic effect of photothermal and photodynamic antibacterial therapy. Next, the recombined human epidermal growth factor (rhEGF) is physically absorbed on the surface of the porous hydrogel to form a RB/PPy/rhEGF hybrid PVA HD (rhEGF/RB/PPy PVA HD). The introduction of rhEGF enables the hydrogel to promote fibroblast proliferation and collagen secretion. Furthermore, the in vivo results indicate that the rhEGF/RB/PPy PVA HD can control infection effectively and promote wound healing significantly.


Assuntos
Infecções Bacterianas , Hidrogéis , Antibacterianos/farmacologia , Humanos , Polímeros , Pirróis , Cicatrização
17.
Ecotoxicol Environ Saf ; 213: 111981, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33592372

RESUMO

Environmental pollution due to resistance genes from livestock manure has become a serious issue that needs to be resolved. However, little studies focused on the removal of resistance genes in simultaneous processing of livestock feces and urine. This study investigated the fate of antibiotic resistance genes (ARGs), metal resistance genes (MRGs), and class 1 integron-integrase gene (intI1) during thermophilic fermentation of swine manure in an ectopic fermentation system (EFS), which has been regarded as a novel system for efficiently treating both feces and urine. The abundances of MRGs and tetracycline resistance genes were 34.44-97.71% lower in the EFS. The supplementation of heavy metals significantly increased the abundance of intI1, with the enhancement effect of copper being more prominent than that of zinc. The highest abundances of resistance genes and intI1 were observed at high Cu levels (A2), indicating that Cu can increase the spreading of resistance genes through integrons. Network analysis revealed the co-occurrence of ARGs, MRGs, and intI1, and these genes potentially shared the same host bacteria. Redundancy analysis showed that the bacterial community explained most of the variations in ARGs, and environmental factors had influences on ARGs abundances by modulating the bacterial community composition. The decreased Sphingomonas, Comamonas, Acinetobacter, Lactobacillus, Bartonella, Rhizobium, and Bacteroides were mainly responsible for the reduced resistance genes. These results demonstrate that EFS can reduce resistance genes in simultaneous processing of livestock feces and urine.


Assuntos
Resistência Microbiana a Medicamentos/genética , Fermentação/fisiologia , Genes Bacterianos , Esterco/microbiologia , Metais Pesados/análise , Animais , Antibacterianos/análise , Bactérias/efeitos dos fármacos , Cobre , Integrons , Gado , Esterco/análise , Suínos , Tetraciclina/farmacologia
18.
Biomaterials ; 269: 120634, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33421708

RESUMO

Light-triggered therapy is a prospective method to combat implant-associated infection but near-infrared I (NIR-I) light has insufficient penetrating ability in tissues and local hyperthermia induced by the photothermal treatment may destroy surrounding healthy tissues. Herein, a near-infrared II (NIR-II) phototherapy system composed of upconversion elements doped titanium dioxide nanorods (TiO2 NRs)/curcumin (Cur)/hyaluronic acid (HA)/bone morphogenetic protein-2 (BMP-2) is designed for biomedical titanium and demonstrated to overcome the above hurdles simultaneously. Incorporation of F, Yb, and Ho not only improves the photocatalytic ability, but also renders the implants with the upconversion capability, so that the NRs can generate enough reactive oxygen species (ROS) when irradiated by the NIR-II laser. Furthermore, the combined actions of quorum sensing inhibitors, ROS, and physical puncture by NRs eliminate Staphylococcus aureus biofilms on titanium rapidly at a mild temperature of 45 °C by only requiring irradiation with the 1060 nm laser for only 15 min in vitro and in vivo. The presence of Cur mitigates the immune response and BMP-2 improves osteogenic differentiation, thus accelerating new bone formation. This low-temperature NIR-II light-triggered antibacterial platform has large potential in combating deep-tissue infection in clinical applications.


Assuntos
Biofilmes , Osteogênese , Raios Infravermelhos , Fototerapia , Estudos Prospectivos , Temperatura
19.
J Pathol ; 253(3): 339-350, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33104252

RESUMO

The cathelin-related antimicrobial peptide CRAMP protects the mouse colon from inflammation, inflammation-associated carcinogenesis, and disrupted microbiome balance, as shown in systemic Cnlp-/- mice (also known as Camp-/- mice). However, the mechanistic basis for the role and the cellular source of CRAMP in colon pathophysiology are ill defined. This study, using either epithelial or myeloid conditional Cnlp-/- mice, demonstrated that epithelial cell-derived CRAMP played a major role in supporting normal development of colon crypts, mucus production, and repair of injured mucosa. On the other hand, myeloid cell-derived CRAMP potently supported colon epithelial resistance to bacterial invasion during acute inflammation with exacerbated mucosal damage and higher rate of mouse mortality. Therefore, a well concerted cooperation of epithelial- and myeloid-derived CRAMP is essential for colon mucosal homeostasis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Células Epiteliais/metabolismo , Homeostase/fisiologia , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Animais , Colo/fisiologia , Camundongos , Camundongos Knockout
20.
Environ Pollut ; 272: 115999, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33218775

RESUMO

In this study, ozonesonde data were used to evaluate the impact of different boundary conditions on the vertical distribution of ozone over urban Beijing. The comparison shows that the clean and static boundary conditions, referred to as PROFILE, apparently underestimate the ozone concentration over the upper troposphere and stratosphere, whereas the global chemical transport model (CTM) provides much more reasonable performance. Further investigation reveals that the boundary conditions exert larger impacts over areas with high altitudes and close distances to boundaries, such as the Tibetan Plateau, while they yield weak impacts on regions relatively far from the boundary, such as the North China Plain (NCP). Process analysis was conducted to investigate the modulation of physical and chemical processes on ozone formation in June 2017, illustrating that during the daytime of the high-O3 period, the photochemical reactions within the planetary boundary layer (PBL) almost become the only source favorable to ozone accumulation. Motivated by this phenomenon, we constructed a linear regression and found that the maximum daily 8-hr ozone (MDA8) ozone concentration was highly correlated with the surface ozone change rate and chemical reactions in the PBL during the pollution period, with MDA8 ozone exceeding 70 ppbv over NCP. Based on this relationship as well as the design of numerical experiments, we propose a strategy of dynamic emission control. Firstly, the emission reduction during the peak ozone formation period may weaken the fast chemical reactions in the PBL and subsequent surface ozone concentration. Secondly, emission reduction one or two days prior to an episode might achieve larger ozone reduction through the accumulation effect. Lastly, emission control outside of the NCP may surpass the local impact under favorable meteorological conditions. Therefore, the efficacy of dynamic emission control was striking when both the accumulation and transport effect were taken into consideration.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Ozônio/análise
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