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2.
Front Plant Sci ; 15: 1334907, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476689

RESUMO

Introduction: Sugarcane endophytic nitrogen-fixing bacterium Klebsiella variícola DX120E displayed broad impact on growth, but the exact biological mechanism, especially polyamines (PAs) role, is still meager. Methods: To reveal this relationship, the content of polyamine oxidase (PAO), PAs, reactive oxygen species (ROS)-scavenging antioxidative enzymes, phytohormones, 1-aminocyclopropane-1-carboxylic synthase (ACS), chlorophyll content, and biomass were determined in sugarcane incubated with the DX120E strain. In addition, expression levels of the genes associated with polyamine metabolism were measured by transcriptomic analysis. Results: Genomic analysis of Klebsiella variícola DX120E revealed that 39 genes were involved in polyamine metabolism, transport, and the strain secrete PAs in vitro. Following a 7-day inoculation period, DX120E stimulated an increase in the polyamine oxidase (PAO) enzyme in sugarcane leaves, however, the overall PAs content was reduced. At 15 days, the levels of PAs, ROS-scavenging antioxidative enzymes, and phytohormones showed an upward trend, especially spermidine (Spd), putrescine (Put), catalase (CAT), auxin (IAA), gibberellin (GA), and ACS showed a significant up-regulation. The GO and KEGG enrichment analysis found a total of 73 differentially expressed genes, involving in the cell wall (9), stimulus response (13), peroxidase activity (33), hormone (14) and polyamine metabolism (4). Discussion: This study demonstrated that endophytic nitrogen-fixing bacteria stimulated polyamine metabolism and phytohormones production in sugarcane plant tissues, resulting in enhanced growth. Dual RNA-seq analyses provided insight into the early-stage interaction between sugarcane seedlings and endophytic bacteria at the transcriptional level. It showed how diverse metabolic processes selectively use distinct molecules to complete the cell functions under present circumstances.

3.
Mar Genomics ; 74: 101082, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38485290

RESUMO

Bacteria of the genus Psychrobacter are widely distributed in the global low-temperature marine environment and have been studied for their effects on the settlement and metamorphosis of marine invertebrates. Psychrobacter cibarius AOSW16051 was isolated from the surface water samples of the Baltic Sea on the edge of the Arctic Ocean. Here, we present the complete genome of strain AOSW16051, which consists of a circular chromosome composed of 3,425,040 nucleotides with 42.98% G + C content and a circular plasmid composed of 5846 nucleotides with 38.66% G + C content. The genes predicted in this strain showed its strong outer membrane system, type VI secretion system and adhesion system. Trimeric autotransporter adhesins (TAAs) has been identified in the genome of P. cibarius AOSW16051, which has a variety of biological functions in interacting with host cells. However, there are no reports on TAAs in marine bacteria and aquatic pathogenic bacteria. By analyzing the genomic data, we can gain valuable insights to enhance our understanding of the physiological characteristics of P. cibarius, as well as the biological functions of TAAs and their role in triggering metamorphosis of invertebrate larvae.


Assuntos
Psychrobacter , Psychrobacter/genética , Sistemas de Secreção Tipo V/genética , Adesinas Bacterianas/genética , Nucleotídeos
4.
Molecules ; 28(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894558

RESUMO

In recent years, major economies have implemented carbon reduction and carbon neutrality policies. Furthermore, with advancements in science and technology, carbon dioxide (CO2) is now considered a valuable raw material for producing carbon-based fuels through hydrogenation. Various concentrations of yttrium (referred to as Y hereafter) were introduced to assess their influence on the catalytic performance of CO2 methanation. At a temperature of 300 °C, the catalyst exhibited an impressive CO2 conversion rate of 78.4% and maintained remarkable stability throughout a rigorous 100 h stability assessment. The findings suggest that the inclusion of yttrium (Y) promotes the formation of oxygen vacancies and alkaline sites on the catalyst. This, in turn, enhances the reducibility of nickel species, improves the dispersion of nickel particles, and plays a pivotal role in enhancing thermal stability. Furthermore, it offers an innovative design approach for creating highly efficient composite CO2 methanation catalysts by controlling particle size and harnessing synergistic catalytic effects at the metal/support interface.

5.
J Cosmet Dermatol ; 22(5): 1680-1684, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36721299

RESUMO

BACKGROUND: The risk of recurrence after successful repigmentation in vitiligo has attracted attention from both patients and clinicians. OBJECTIVES: The recurrence rate and risk factors in cured patients with vitiligo were analyzed to improve clinical prevention and treatment. METHODS: Clinical records of 76 patients with vitiligo who demonstrated at least 80% repigmentation were analyzed retrospectively. Single-factor analysis of variance and binary logistic regression analysis was employed to screen the risk factors of vitiligo recurrence. RESULTS: Among the 76 cured patients, 26 relapsed (total recurrence rate of 34.2%). Among these, 20 relapsed within one year (recurrence rate of 26.3%). Single-factor analysis of variance revealed significant differences (p < 0.05) with the age of onset (yr), distribution of onset, and oral traditional Chinese medicine (TCM) intake between the recurrence and nonrecurrence groups. Binary logistic regression analysis displayed that the age of onset (yr) (p = 0.015, OR = 1.051), distribution of onset (p = 0.046, OR = 0.194), and oral TCM (p = 0.018, OR = 4.360) are significant risk factors for vitiligo recurrence. CONCLUSION: A total relapse rate of 34.2% was observed in cured vitiligo patients. The age of onset (yr), distribution of onset, and oral TCM are risk factors for vitiligo recurrence. The necessary interventions should be considered on these factors for reducing the recurrence rate of vitiligo.


Assuntos
Terapia Ultravioleta , Vitiligo , Humanos , Vitiligo/epidemiologia , Vitiligo/terapia , Estudos Retrospectivos , Terapia Combinada , Recidiva , Resultado do Tratamento
6.
J Med Virol ; 95(1): e28387, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478267

RESUMO

Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) is a distinct subtype of gastric cancer (GC) distinguished by the presence of the EBV genome and limited viral gene expression within malignant epithelial cells. EBV infection is generally thought to be a relatively late event following atrophic gastritis in carcinogenesis, which implies the heterogeneity of EBVaGC. To facilitate the study of the role of EBV in EBVaGC, we established two EBV-positive GC cell lines (AGS-EBV and HGC27-EBV) with an epitheliotropic EBV strain M81 and characterized viral and cellular gene expression profiles in comparison to SNU719, a naturally derived EBV-positive GC cell line. Like SNU719, AGS-EBV and HGC27-EBV stably maintained their EBV genomes and expressed EBV-encoded small RNAs and nuclear antigen EBNA1. Comprehensive analysis of the expression of EBV-encoded miRNAs within the BamHI-A region rightward transcript region, and the transcripts of EBV latent and lytic genes in cell lines, as well as xenografts, reveals that AGS-EBV and HGC27-EBV cells undergo distinct viral expression profiles. A very small fraction of AGS-EBV and SNU719 cells can spontaneously produce infectious progeny virions, while HGC27-EBV does not. AGS-EBV (both M81 and Akata) cells largely mimic SNU719 cells in viral gene expression profiles, and altered cellular functions and pathways perturbed by EBV infection. Phylogenetic analysis of the EBV genome shows both M81 and Akata EBV strains are closely related to clinical EBVaGC isolates. Taken together, these two newly established EBV-positive GC cell lines can serve as models to further investigate the role of EBV in different contexts of gastric carcinogenesis and identify novel therapeutics against EBVaGC.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Carcinogênese , Linhagem Celular/metabolismo , Linhagem Celular/virologia , Herpesvirus Humano 4/genética , Filogenia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/virologia
7.
Genes (Basel) ; 13(12)2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36553651

RESUMO

Metamorphosis is a critical process in the transition from planktonic life to benthic life for marine invertebrates, which is accompanied by a large amount of energy consumption. Previous studies have proved that AMP-activated protein kinase (AMPK), as a vital energy regulator, plays a prominent role in mediating the growth and development of terrestrial animals. However, its function in the growth and development of marine invertebrates, especially in metamorphosis, remains elusive. This study explored the function of AMPK in the larval metamorphosis of Mytilus coruscus. The full-length cDNA of AMPK genes in M. coruscus was cloned and characterized, which is composed of three subunits, McAMPKα, McAMPKß, and McAMPKγ. Pharmacological tests demonstrated that through the application of an AMPK activator, AMP substantially enhanced the larval metamorphosis rate (p < 0.05). By contrast, the larval metamorphosis rate decreased significantly after being treated with the AMPK inhibitor Compound C (p < 0.05). McAMPK gene knock-down resulted in a reduction in McAMPK gene expression (p < 0.05), and the larval metamorphosis of M. coruscus was significantly restrained (p < 0.05). These results indicated that AMPK signaling is vital in the larval metamorphosis of M. coruscus, which advances further understanding in exploring the molecular mechanisms in the metamorphosis of marine invertebrate larvae.


Assuntos
Mytilus , Animais , Mytilus/genética , Proteínas Quinases Ativadas por AMP/genética , Metamorfose Biológica/genética , Larva/genética
8.
Phytomedicine ; 106: 154430, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36099656

RESUMO

BACKGROUND: Acupuncture is commonly used for cancer-related conditions worldwide, and evidence is increasing year on year. There is a need to summarize the evidence of acupuncture for cancer-related conditions comprehensively and critically. OBJECTIVE: To evaluate and summarize the systematic reviews (SRs) that assess the effects and safety of acupuncture for cancer-related conditions, and to inform clinical practice and future studies. METHODS: A comprehensive search was conducted on Pubmed, Embase, the Cochrane Library, Web of Science, CNKI, VIP, Sinomed, and Wanfang from their inception to October 16, 2021. SRs of randomized controlled trials (RCTs) on acupuncture for cancer-related conditions were to be included. Two reviewers screened the eligible articles, and four reviewers in pair extracted data and assessed the methodological quality/risk of bias of all included reviews by AMSTAR 2 and ROBIS tools. The overlap of primary studies was measured by calculating corrected covered areas. Data from the included reviews were synthesized with a summary of meta-analysis or narrative description. RESULTS: Fifty-one SRs of RCTs on acupuncture for cancer-related conditions were included and synthesized. The methodological quality of SRs included 1 "high", 5 "low" and 45 "very low" by AMSTAR 2. Sixteen SRs assessed as low risk of bias (31.37%), and 35 SRs had high risk of bias (68.63%) by ROBIS. Acupuncture showed effective on systemic conditions in relation to different cancers, including cancer-related pain (17 SRs, 80 RCTs), fatigue (7 SRs, 18 RCTs), insomnia (4 SRs, 10 RCTs), quality of life (2 SRs, 15 RCTs); conditions in relation to chemo-radiotherapy, including nausea and vomiting (3 SRs, 36 RCTs) and bone marrow suppression (2 SRs, 21 RCTs); and conditions in relation to specific cancers, including breast cancer-related menopause (3 SRs, 6 RCTs), hot flashes (12 SRs, 13 RCTs), arthralgia (5 SRs, 10 RCTs), and nasopharyngeal cancer-related dysphagia (1 SRs, 7 RCTs). Acupuncture appeared to have benefit for patients with lymphoedema (3 SRs, 3 RCTs), gastrointestinal function (5 SRs, 27 RCTs), and xerostomia (4 SRs, 7 RCTs). Limited evidence showed inconsistent results on acupuncture for chemotherapy-induced peripheral neuropathy (3 SRs, 6 RCTs), depression and anxiety (3 SRs, 9 RCTs). Acupuncture was regarded as a safe therapy for cancer patients as no severe adverse events related were reported. CONCLUSION: Evidence from SRs showed that acupuncture is beneficial to cancer survivors with cancer-related pain, fatigue, insomnia, improved quality of life, nausea and vomiting, bone marrow suppression, menopausal symptoms, arthralgia, and dysphagia, and may also be potential for lymphoedema, gastrointestinal function, and xerostomia. For neuropathy, depression and anxiety, acupuncture should be used as an option based on individual conditions. Acupuncture is relatively safe without serious adverse events. More well-designed clinical trials of acupuncture are recommended on cancer-related depression and anxiety, arthralgia, xerostomia, gastrointestinal dysfunction and dysphagia.


Assuntos
Terapia por Acupuntura , Antineoplásicos , Dor do Câncer , Transtornos de Deglutição , Linfedema , Neoplasias , Distúrbios do Início e da Manutenção do Sono , Xerostomia , Terapia por Acupuntura/métodos , Artralgia/etiologia , Transtornos de Deglutição/etiologia , Fadiga , Feminino , Humanos , Linfedema/etiologia , Náusea/etiologia , Neoplasias/etiologia , Neoplasias/terapia , Revisões Sistemáticas como Assunto , Vômito/etiologia , Xerostomia/etiologia
9.
Zhen Ci Yan Jiu ; 47(7): 649-54, 2022 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-35880285

RESUMO

A multi-parameter controllable automatic fire-acupuncture instrument was developed by integrating traditional fire needling with modern medical device technology. A gun-like appearance was designed for easy hand-held operation, the electromagnetic induction was for heating needle body, a scale knob was for controlling the needle insertion depth, the combination of electromagnetic ejection and spring return was for the precise control of the needle retention time; and the changeable single ste-rile needle or multiple needles were adopted to meet individual demand, obtain high efficiency and prevent infection. All of these designs are associated with the overall process control system to ensure the exact controllability of needle body temperature, needling density, insertion depth and needle retention time. Besides, this device is advantageous at handy and aseptic operation with high efficiency, conformability and visualization. In this research, this instrument was tested in animals for the impacts of automatic fire needling on skin damage and fur growth. It is found that the accurate control of each parameter is of the significant advantage in the safety and effectiveness of treatment, which lays a solid foundation for the subsequent systematic review on safety and effectiveness.


Assuntos
Terapia por Acupuntura , Agulhas
10.
Polymers (Basel) ; 14(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35566974

RESUMO

The nanoparticles dispersion system has complex migration characteristics and percolation law in porous media due to the interaction between the nanoparticles and porous media. In this paper, lab experiments were carried out to characterize the morphology, particle size distributions, and apparent viscosities of SiO2/P(MBAAm-co-AM) polymeric nanoparticle solution, investigate its migration characteristics in porous media, and probe its capability of enhanced oil recovery (EOR) in the reservoirs. Quartz microtubule, sand pack, and etched glass micromodels were used as the porous media in the flow and flooding experiments. Gray image-processing technology was applied to achieve oil saturation at different flooding stages in the micromodel for calculating the EOR of the SiO2/P(MBAAm-co-AM) polymeric nanoparticle solution. The results show that The SiO2/P(MBAAm-co-AM) polymeric nanoparticles are spherical with diameters ranging from 260 to 300 nm, and the thicknesses of the polymeric layers are in the range of 30-50 nm. As the swelling time increases from 24 to 120 h, the medium sizes of the SiO2/P(MBAAm-co-AM) polymeric nanoparticles increase from 584.45 to 1142.61 nm. The flow of the SiO2/P(MBAAm-co-AM) polymeric nanoparticles has obvious nonlinear characteristics and a prominent scale effect at a low-pressure gradient, and there should be an optimal matching relationship between its injection mass concentration and the channel size. The flow tests in the sand packs demonstrate that the SiO2/P(MBAAm-co-AM) polymeric nanoparticles can form effective plugging in the main flow channels at different permeability areas and can break through at the throat to fulfill the step-by-step profile control. Moreover, the profile control of the SiO2/P(MBAAm-co-AM) polymeric nanoparticles strengthens with an increase in their swelling time. The microscopic flooding experiment in the etched glass micromodel confirms that the SiO2/P(MBAAm-co-AM) polymeric nanoparticles can block dynamically and alternatively the channels of different sizes with the form of loose or dense networks to adjust the fluid flow diversion, improve the sweep efficiency, and recover more residual oil. The SiO2/P(MBAAm-co-AM) polymeric nanoparticles can achieve an enhanced oil recovery of 20.71% in the micromodel.

11.
Plant Physiol ; 190(1): 621-639, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35640107

RESUMO

Pre-mRNA splicing is an important step in the posttranscriptional processing of transcripts and a key regulator of development. The heterotrimeric retention and splicing (RES) complex plays vital roles in the growth and development of yeast, zebrafish, and humans by mediating pre-mRNA splicing of multiple genes. However, whether the RES complex is conserved in plants and what specific functions it has remain unknown. In this study, we identified Arabidopsis (Arabidopsis thaliana) BUD13 (AtBUD13), GROWTH, DEVELOPMENT AND SPLICING 1 (GDS1), and DAWDLE (DDL) as the counterparts of the yeast RES complex subunits Bud site selection protein 13 (Bud13), U2 snRNP component Snu17 (Snu17), and Pre-mRNA leakage protein 1, respectively. Moreover, we showed that RES is an ancient complex evolutionarily conserved in eukaryotes. GDS1 directly interacts with both AtBUD13 and DDL in nuclear speckles. The BUD13 domain of AtBUD13 and the RNA recognition motif domain of GDS1 are necessary and sufficient for AtBUD13-GDS1 interaction. Mutants of AtBUD13, GDS1, and DDL failed to properly splice multiple genes involved in cell proliferation and showed defects in early embryogenesis and root development. In addition, we found that GDS1 and DDL interact, respectively, with the U2 small nuclear ribonucleoproteins auxiliary factor AtU2AF65B and the NineTeen Complex-related splicing factor SKIP, which are essential for early steps of spliceosome assembly and recognition of splice sites. Altogether, our work reveals that the Arabidopsis RES complex is important for root and early embryo development by modulating pre-mRNA splicing.


Assuntos
Arabidopsis , Animais , Arabidopsis/metabolismo , Desenvolvimento Embrionário , Humanos , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Ribonucleoproteína Nuclear Pequena U2/genética , Ribonucleoproteína Nuclear Pequena U2/metabolismo , Saccharomyces cerevisiae/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
12.
Stem Cells Dev ; 31(5-6): 111-118, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35044224

RESUMO

Extrinsic injury can evoke intrinsic stimulation and subsequently initiate the physiological repair process. This study aims to investigate whether clinically acceptable micro-injury could be used to create local stimuli to induce hair regeneration and vitiligo repigmentation. A novel device was designed and manufactured to precisely control the micro-injury parameters. Then the most appropriate extent of micro-injury without over-damaging the skin was evaluated. Finally, the effects of micro-injury on hair regeneration and vitiligo repigmentation were examined by macroscopic observation, histological staining, gene and protein expression analysis. We discover that proper micro-injury effectively induces hair regeneration by activating the hair follicle stem cell proliferation and migration downwards to the hair matrix, finally shifting the hair follicle stage from telogen into anagen. On vitiligo model mice, micro-injury also induces the hair follicle melanocyte stem cells to migrate upwards to the interfollicular epidermis, activating and giving rise to melanocytes to repopulate the vitiligo lesion. Mechanistic analysis indicates that the canonical Wnt/ß-catenin pathway plays a key role in the micro-injury-induced repair process. This study demonstrates that micro-injury has great potential in inducing hair regeneration and vitiligo repigmentation, laid a foundation to develop a micro-injury-based treatment method in alopecia and vitiligo.


Assuntos
Vitiligo , Animais , Cabelo , Folículo Piloso , Melanócitos/patologia , Camundongos , Vitiligo/metabolismo , Vitiligo/patologia , Vitiligo/terapia , beta Catenina/genética , beta Catenina/metabolismo
13.
ACS Omega ; 6(28): 18200-18214, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34308051

RESUMO

Mechanical properties are some of the most important parameters for understanding well drilling and hydraulic fracturing designs in unconventional reservoir development. As an effective tool, nanoindentation has been used to determine the mechanical properties of rocks at the nanoscale. In this study, the Longmaxi Formation shale samples from the Yibin area of China were collected and analyzed to obtain the multiphase mechanical properties. The mineral compositions and organic geochemistry of the shale samples were studied using X-ray diffraction, energy-dispersive X-ray spectrometry, and a carbon/sulfur analyzer. The pore structures of the shale samples at the micro- and nanoscales were characterized by field-emission scanning electron microscopy. The mechanical parameters of the shale samples, such as the hardness and elastic modulus, were investigated using the nanoindentation method to identify three mineral phases: brittle minerals, soft matters, and complex minerals at the interfaces between brittle minerals and soft matters. The uncertainty characteristics of the mechanical parameters of the three mineral phases were evaluated using the Weibull model, and the factors interfering with the mechanical parameters were analyzed for the different shale samples. The results showed that the brittle minerals had the largest recovered elastic deformations and the smallest residual deformations, while the soft matters had the largest residual deformations and the smallest recovered elastic deformations. The analysis results of the coefficients of variation and the Weibull modulus both confirmed that the scatter of the hardness was higher than that of the elastic modulus because of the uncertain contact area, and the hardness and elastic modulus of the soft matters had the highest uncertainty among the three mineral phases. The elastic modulus increased nonlinearly with increasing hardness according to a power function for the whole shale sample. The elastic modulus and hardness both had a favorable linear relationship with the total organic carbon (TOC) content, illustrating that the TOC content was one of the significant factors that affected the mechanical parameters of the shale samples.

14.
EMBO Mol Med ; 13(7): e14089, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34102002

RESUMO

The tyrosine phosphatase SHP2 is oncogenic in cancers driven by receptor-tyrosine-kinases, and SHP2 inhibition reduces tumor growth. Here, we report that SHP2 is an essential promoter of endothelial cell survival and growth in the remodeling tumor vasculature. Using genetic and chemical approaches to inhibit SHP2 activity in endothelial cells, we show that SHP2 inhibits pro-apoptotic STAT3 and stimulates proliferative ERK1/2 signaling. Systemic SHP2 inhibition in mice bearing tumor types selected for SHP2-independent tumor cell growth promotes degeneration of the tumor vasculature and blood extravasation; reduces tumor vascularity and blood perfusion; and increases tumor necrosis. Reduction of tumor growth ensues, independent of SHP2 targeting in the tumor cells, blocking immune checkpoints, or recruiting macrophages. We also show that inhibiting the Angiopoietin/TIE2/AKT cascade magnifies the vascular and anti-tumor effects of SHP2 inhibition by blocking tumor endothelial AKT signaling, not a target of SHP2. Since the SHP2 and Ang2/TIE2 pathways are active in vascular endothelial cells of human melanoma and colon carcinoma, SHP2 inhibitors alone or with Ang2/TIE2 inhibitors hold promise to effectively target the tumor endothelium.


Assuntos
Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Animais , Células Endoteliais/metabolismo , Camundongos , Neoplasias/tratamento farmacológico , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Receptores Proteína Tirosina Quinases , Transdução de Sinais
15.
J Mater Chem B ; 9(10): 2469-2482, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33646220

RESUMO

Inspired by the nanostructure of bone, biomimetic nanocomposites comprising natural polymers and inorganic nanoparticles have gained much attention for bone regenerative applications. However, the mechanical and biological performances of nanocomposites are largely limited by the inhomogeneous distribution, uncontrolled size and irregular morphology of inorganic nanoparticles at present. In this work, an innovative in situ precipitation method has been developed to construct a biomimetic nanocomposite which consists of spherical hydroxyapatite (HA) nanoparticles and gelatin (Gel). The homogeneous dispersion of HA nanoparticles in nHA-Gel endowed it with a low swelling ratio, enhanced mechanical properties and slow degradation. Moreover, strontium (Sr) was incorporated into HA nanoparticles to further enhance the bioactivity of nanocomposites. In vitro experiments suggested that nHA-Gel and Sr-nHA-Gel facilitated cell spreading and promoted osteogenic differentiation of bone-marrow-derived mesenchymal stem cells (BMSCs) as compared to pure Gel and mHA-Gel conventional composites developed by mechanical mixing. In vivo rat critical-sized calvarial defect repair further confirmed that nHA-Gel and Sr-nHA-Gel possessed relatively effective bone regenerative abilities among the four groups. Collectively, the biomimetic nanocomposites of nHA-Gel and Sr-nHA-Gel have good efficacy in inducing bone regeneration and would be a promising alternative to bone grafts for clinical applications.


Assuntos
Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Durapatita/química , Nanocompostos/química , Nanopartículas/química , Animais , Diferenciação Celular/efeitos dos fármacos , Gelatina/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos , Estrôncio/química
16.
Front Plant Sci ; 12: 622201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33613604

RESUMO

Abscisic acid (ABA) is an important phytohormone regulating plant growth, development and stress responses. A multitude of key factors implicated in ABA signaling have been identified; however, the regulation network of these factors needs for further information. AtS40.4, a plant-specific DUF584 domain-containing protein, was identified previously as a senescence regulator in Arabidopsis. In this study, our finding showed that AtS40.4 was negatively involved in ABA signaling during seed germination and early seedling growth. AtS40.4 was highly expressed in seeds and seedlings, and the expression level was promoted by ABA. AtS40.4 was localized both in the nucleus and the cytoplasm. Moreover, the subcellular localization pattern of AtS40.4 was affected by ABA. The knockdown mutants of AtS40.4 exhibited an increased sensitivity to ABA, whereas the overexpression of AtS40.4 decreased the ABA response during seed germination and seedling growth of Arabidopsis. Furthermore, AtS40.4 was involved in ABRE-dependent ABA signaling and influenced the expression levels of ABA INSENTIVE (ABI)1-5 and SnRK2.6. Further genetic evidence demonstrated that AtS40.4 functioned upstream of ABI4. These findings support the notion that AtS40.4 is a novel negative regulator of the ABA response network during seed germination and early seedling growth.

17.
J Med Virol ; 93(3): 1370-1377, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33095513

RESUMO

Renin-angiotensin-aldosterone system (RAAS) inhibitors, including angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are one of the most prescribed antihypertensive medications. Previous studies showed RAAS inhibitors increase the expression of ACE2, a cellular receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which provokes a concern that the use of ACEI and ARB in hypertensive individuals might lead to increased mortality and severity of coronavirus disease 2019 (COVID-19). To further investigate the effects of ACEI/ARB on COVID-19 patients, we systematically reviewed relevant studies that met predetermined inclusion criteria in search of PubMed, Embase, Cochrane Library databases, medRxiv, and bioRxiv. The search strategy included clinical data published through October 12, 2020. Twenty-six studies involving 8104 hypertensive patients in ACEI/ARB-treated group and 8203 hypertensive patients in non-ACEI/ARB-treated group were analyzed. Random-effects meta-analysis showed ACEI/ARB treatment was significantly associated with a lower risk of mortality in hypertensive COVID-19 patients (odds ratio [OR] = 0.624, 95% confidence interval [CI] = 0.457-0.852, p = .003, I2 = 74.3%). Meta-regression analysis showed that age, gender, study site, Newcastle-Ottawa Scale scores, comorbidities of diabetes, coronary artery disease, chronic kidney disease, or cancer has no significant modulating effect of ACEI/ARB treatment on the mortality of hypertensive COVID-19 patients (all p > .1). In addition, the ACEI/ARB treatment was associated with a lower risk of ventilatory support (OR = 0.682, 95% CI = 0.475-1.978, p = .037, I2 = 0.0%). In conclusion, these results suggest that ACEI/ARB medications should not be discontinued for hypertensive patients in the context of COVID-19 pandemic.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , COVID-19/complicações , COVID-19/mortalidade , Hipertensão/tratamento farmacológico , Comorbidade , Feminino , Humanos , Hipertensão/complicações , Masculino , Prognóstico , Fatores de Risco
18.
Environ Monit Assess ; 192(8): 523, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32676738

RESUMO

Unfortunately, the name of the corresponding author (Wenxiang Wu) was missing in the author group section of the published paper.

19.
Environ Monit Assess ; 192(7): 464, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601791

RESUMO

Ground deformation (GD) has been widely reported as a global issue and is now an ongoing problem that will profoundly endanger the public safety. GD is a complex and dynamic problem with many contributing factors that occur over time. In the literature, there are only a few methods that can effectively monitor GD. Microwave remote sensing data such as interferometric synthetic aperture radar (InSAR) are mostly adopted to assess GD. These data can reveal the surface deforming areas with great precision, mapping GD results at a large scale. In this study, the effects of GD and the influencing factors, such as the building area, the water level, the cumulative precipitation, and the cumulative temperature, are modeled in the Erhai region with small baseline subset interferometric SAR (SBAS-InSAR) data that are applied using machine learning (ML) methods. The ML methods, namely, multiple linear regression (MLR), multilayer perceptron backpropagation (MLP-BP), least squares support vector machine (LSSVM), and particle swarm optimization (PSO)-LSSVM, are used to predict GD, and the results are compared. Particularly, the PSO-LSSVM method has obtained the least root mean square error (RMSE) and mean relative error (MRE) of 11.448 and 0.112, respectively. Therefore, the results have proven that the proposed PSO-LSSVM is very efficient in analyzing GD.


Assuntos
Monitoramento Ambiental , Aprendizado de Máquina , China , Redes Neurais de Computação , Máquina de Vetores de Suporte
20.
Nanoscale ; 12(13): 7284-7300, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32196048

RESUMO

Biomimicking the nanostructure of natural bone apatite to enhance the bioactivity of hydroxyapatite (HA) biomaterials is an eternal topic in the bone regeneration field. In the present study, we designed four kinds of HA bioceramics with micro- to nanosized grains and investigated the effects of bioceramic topographies on the structures of bone morphogenetic protein-2 (BMP-2) and the effects on the responses of bone marrow stromal cells (BMSCs). Compared to the samples with submicron-scale crystalline particles, HA bioceramics with grain sizes of 104.6 ± 27.8 nm exhibited increased roughness, improved hydrophilicity and enhanced mechanical properties. The synergistic effects of these surface characteristics could well maintain the conformation of BMP-2, facilitate cell adhesion and spreading, and activate the osteogenic differentiation of BMSCs. Furthermore, SBF immersion and in vivo canine intramuscular implantation confirmed that the HA bioceramics with nanotopography also processed excellent bone-like apatite forming ability and outstanding osteoinductivity. In summary, these findings suggest that the nanotopography of HA bioceramics is a critical factor to enhance their bioactivity and osteoinductivity.


Assuntos
Materiais Biomiméticos , Proteína Morfogenética Óssea 2 , Diferenciação Celular/efeitos dos fármacos , Cerâmica , Durapatita , Células-Tronco Mesenquimais/metabolismo , Nanoestruturas , Osteogênese/efeitos dos fármacos , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Cerâmica/química , Cerâmica/farmacologia , Durapatita/química , Durapatita/farmacologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células-Tronco Mesenquimais/citologia
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