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1.
Opt Express ; 29(21): 32778-32795, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809101

RESUMO

In this work, a dynamic resource allocation (DRA) algorithm is proposed to optimize the transmission rate subject to the access point assignment, bandwidth and transmit power allocation in RF/VLC heterogeneous networks, which combines the visible light communication (VLC) access point (AP) and radio frequency (RF) AP. To optimize the allocation among resource block (RB), subchannel and power, the time-average transmission rate is maximized under time-average transmit power budget. Specifically, the time-average optimization problem is converted into series of single timeslot online problem by Lyapunov optimization technique. Because of its complexity and non-convexity, the problem is decomposed into three independent subproblems for which a non-iterative solution is presented on the basis of Lagrange relaxation and convex optimization theory. Numerical simulations are conducted to demonstrate the effectiveness of the proposed DRA algorithm. And the comparisons with two classical algorithms are also given in terms of transmission rate and system stability. This work will benefit the design and development of hybrid RF/VLC system.

2.
Inorg Chem ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34822248

RESUMO

The template-assisted route is an effective avenue for the preparation of core-shell and hollow micromaterials. However, the conversion process is usually characterized by ex situ transmission electron microscopy, limiting the comprehensive understanding of the structure evolution. Here, we use dark-field microscopy (DFM) to visually image the chemical conversion process of Cu2O concave microcubes into metal hydroxide (MHs, M = Co, Ni, and Mn) microstructures at the single-particle level. The details of the conversion process such as early steps in the conversion reaction, intermediate states, and final states are successfully tracked in real time. The in situ DFM experiments clarify that the etching of Cu2O predates the generation of MHs, and the conversion reaction shows significant particle-to-particle variation. Meanwhile, the results also show that experimental parameters dominate the conversion of Cu2O concave microcubes, allowing for the precise manipulation of the reaction degree to obtain Cu2O@Co(OH)2 core-shell microstructures with different shell thicknesses and hollow Co(OH)2 microstructures. The present work offers a direct observation and manipulation of the conversion process of Cu2O microparticles, paving the way for rational design and preparation of various core-shell and hollow micromaterials.

3.
Small ; : e2105083, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34825480

RESUMO

Metal deposition with photocatalyst is a promising way to surmount the restriction of fast e- /h+ recombination to improve the photocatalytic performance. However, the improvement remains limited by the existing strategies adopted for depositing metal particles due to the serious aggregation and large unconnected area on photocatalyst surface. Here, a strategy is proposed by directly grafting hypercrosslinked polymers (HCPs) on TiO2 surface to construct Pd-HCPs-TiO2 composite with uniform dispersion of ultrafine Pd nanoparticles on HCPs surface. This composite with surface area of 373 m2 g-1 exhibits improved photocatalytic CO2 conversion efficiency to CH4 with an evolution rate of 237.4 µmol g-1 h-1 and selectivity of more than 99.9%. The enhancement can be ascribed to the grafted porous HCPs with high surface area and N heteroatom on TiO2 surface for the stabilization of Pd nanoparticles, favoring the electron transfer and CO2 adsorption for selective CH4 production. This strategy may hold the promise for design and construction of porous organic polymer with semiconductor for efficient photocatalytic conversion.

4.
Ecotoxicol Environ Saf ; 228: 112956, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34781132

RESUMO

Benzene exposure leads to hematopoietic dysfunction and is characterized clinically by a decrease in blood cells, but the underlying mechanisms remain elusive. Disturbed gut microbiota may induce host metabolic, immune disorders and the onset of disease. However, the characterization of gut microbiota, metabolism, cytokines and their association with benzene-induced hematopoietic toxicity lacks systematic evidence. Here, the microbiomics, metabolomics and cytokine network were applied to find out the critical characteristics of gut microbiota, metabolism and cytokines in mice involved in the benzene-induced hematopoietic toxicity. We found that the decline in hematopoietic stem cells was earlier than the hematological changes in the 5 mg/kg and 25 mg/kg benzene exposure groups. While 125 mg/kg benzene exposure resulted in a significant decline in whole blood cells. High-throughput sequencing results showed that benzene exposure disrupted homeostasis of gut microbiota, metabolism and cytokine in mice. 6 bacteria, 12 plasma metabolites and 6 cytokines were associated with benzene-induced hematopoietic damage. Notably, IL-5 was significantly increased in benzene exposure group in a dose-dependent manner, and a significant negative correlation was found between IL-5 and hematopoietic damage. We further found that increased Family_XIII_AD3011_group at the genus level and decreased Anaerotruncus_sp at the species level in benzene-exposed group were strongly associated with hematopoietic toxicity and IL-5. Furthermore, the abundance of Family_XIII_AD3011_group and Anaerotruncus_sp were negatively correlated with Adipic acid and 4-Hydroxyproline, respectively. Our findings indicated that altered flora structure of gut microbiota affects the metabolic phenotype which acts as messengers for the gut microbes, affecting host inflammation. This preliminary study provides new insight into the potential mechanisms of benzene-induced hematopoietic toxicity, further exploration by functional studies is required in the future.

5.
Materials (Basel) ; 14(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34771931

RESUMO

To achieve the requirements of modified bismaleimide resin composites in electronic industry and high energy storage devices, flame retardancy, water resistance and dielectric properties must be improved. Hence, a highly efficient multifunctional graphene nanoplatelets hybrid flame retardant is prepared by ionic liquid graphite and ammonium polyphosphate. The preparation processes of the flame retardants are simple, low energy consumption and follow the green chemical concept of 100% utilization of raw materials, compared with chemical stripping. The bismaleimide resin containing 10 wt.% of the flame retardant show good flame retardancy, resulting in the limiting oxygen index increases to above 43%, and the peak heat release rate, total heat release and total smoke release decrease by 41.8%, 47.8% and 52.3%, respectively. After soaking, mass loss percentage of the modified bismaleimide resin only decreases by 0.96%, the dielectric constant of the composite increases by 39.4%, and the dielectric loss decreases with the increase of frequency. The hybrid flame retardants show multifunctional effect in the modified bismaleimide resin, due to the physical barrier, the chemical char-formation, hydrophobicity and strong conductivity attributed to co-work of Graphene nanoplatelets, ammonium polyphosphate and ionic liquid.

6.
Front Pharmacol ; 12: 683818, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594215

RESUMO

Background and objective: Abnormal activation of Janus kinase 2 (JAK2) promotes the pathogenesis and progress of inflammatory bowel disease (IBD) by stimulating the cytokine traffic. Based on docking studies, arbutin, a natural product extracted from a traditional medicinal plant bearberry, was found to bind to JAK2. The study aimed to investigate the effects and mechanisms of regulating JAK2 by arbutin on colitis in mice. Methods: A mice colitis model was established to mimic human IBD. The mice freely drank water containing dextran sulfate sodium. Inflammation in epithelial (IEC6) and immune (RAW264.7) cells was analyzed following treatment with lipopolysaccharides (LPS). Results: Colitis symptoms, including body weight loss, increased disease activity index, and increased colon weight/length ratio, were significantly alleviated by arbutin. Mediators of colonic pro-inflammatory cytokines as well as apoptosis markers in colitis were suppressed by the glycoside. High expression of phosphorylated JAK2 in colitis was significantly reversed by arbutin. The effects of arbutin treatment on colitis were considerably inhibited by the JAK2 inhibitor AG490. LPS-induced inflammatory responses were also suppressed by arbutin, which was notably inhibited by the JAK2 inhibitor AG490. Conclusion: The findings obtained herein suggest the protective role of arbutin and provide novel insights into alternative colitis treatments, which involve inhibition of the JAK2 signaling pathway.

7.
Bioengineered ; 12(1): 6771-6781, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34515612

RESUMO

Cardiac hypertrophy is an adaptive response of the myocardium to the pressure overload of the heart. MicroRNAs (miRNAs/miRs) are shown to be directly involved in the development of cardiac hypertrophy. However, the function of miR-337-5p and its potential contribution to the serine/threonine-protein kinase, a mammalian target of rapamycin (mTOR) signaling in cardiac hypertrophy remains unknown. In the present study, miR-337-5p expression was examined in cardiomyocytes treated with angiotensin II (Ang II). An adenovirus vector system was employed to knockdown miR-337-5p expression to investigate its functions in cardiac hypertrophy. The results revealed a significant increase in the expression of miR-337-5p in cardiomyocytes treated with Ang II as compared with controls. In addition, downregulation of miR-337-5p expression inhibited cardiac hypertrophy both in vitro and in vivo. Dual-luciferase reporter assays demonstrated Ubiquilin-1 (UBQLN1) as the direct target of miR-337-5p, and revealed its function in the modulation of mTOR signaling. Rescue experiments indicated that UBQLN1 overexpression reversed the effects of miR-337-5p, and further verified this interaction. In summary, the results of the present study show that miR-337-5p silencing attenuates cardiac hypertrophy by targeting UBQLN1. Therefore, miR-337-5p plays a critical role in cardiac hypertrophy and may serve as a new therapeutic target.

8.
Front Pharmacol ; 12: 729414, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504431

RESUMO

Naringin has been shown to exert protective effects in an animal model of ulcerative colitis, but detailed mechanisms remain unclear. This study aimed to investigate function and signaling mechanisms underlying naringin-induced therapeutic effects on colitis. Two mouse models were established to mimic human Inflammatory bowel disease (IBD) by treating drinking water with dextran sodium sulphate or intra-colonic administration of 2, 4, 6-trinitrobenzene sulfonic acid. Transcriptomics combined with functional experiments were used to investigate underlying mechanisms. Colitis symptoms, including weight loss and high disease activity index were significantly reversed by naringin. The inflammatory response, oxidative reactions, and epithelial cell apoptosis that occur with colitis were also alleviated by naringin. After naringin treatment, transcriptomics results identified 753 differentially expressed mRNAs that were enriched in signaling pathways, including the neuroactive ligand-receptor interaction, calcium signaling, and peroxisome proliferator-activated receptor (PPAR) signaling. The naringin-induced alleviation of colitis was significantly inhibited by the PPAR-γ inhibitor BADGE. In IEC-6 and RAW264.7 cells incubated with lipopolysaccharide (LPS), NF-κB-p65, a downstream protein of PPAR-γ, was significantly increased. Naringin suppressed LPS-induced high expression of NF-κB-p65, which was inhibited by small interfering RNA targeting PPAR-γ. Our study clarifies detailed mechanisms underlying naringin-induced therapeutic effects on mice colitis, and PPAR-γ was found to be the main target of naringin by functional experiments both in vivo and in vitro. Our study supplies new scientific information for the use of naringin in colitis treatment.

9.
Arch Virol ; 166(11): 2975-2988, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34524535

RESUMO

Porcine deltacoronavirus (PDCoV) is one of the most important enteropathogenic pathogens, and it causes enormous economic losses to the global commercial pork industry. PDCoV was initially reported in Hong Kong (China) in 2012 and subsequently emerged in swine herds with diarrhea in Ohio (USA) in 2014. Since then, it has spread to Canada, South Korea, mainland China, and several Southeast Asian countries. Information about the epidemiology, evolution, prevention, and control of PDCoV and its prevalence in China has not been comprehensively reported, especially in the last five years. This review is an update of current information on the general characteristics, epidemiology, geographical distribution, and evolutionary relationships, and the status of PDCoV vaccine development, focusing on the prevalence of PDCoV in China and vaccine research in particular. Together, this information will provide us with a greater understanding of PDCoV infection and will be helpful for establishing new strategies for controlling this virus worldwide.


Assuntos
Infecções por Coronavirus/veterinária , Deltacoronavirus/genética , Deltacoronavirus/patogenicidade , Doenças dos Suínos/epidemiologia , Vacinas Virais/farmacologia , Animais , Evolução Biológica , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Especificidade de Hospedeiro , Filogenia , Prevalência , Suínos , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-34546929

RESUMO

Feature selection and feature extraction, in the field of data dimensionality reduction, are the two main strategies. Nevertheless, each of these two strategies has its own advantages and disadvantages. The features chosen by feature selection method have complete physical meaning. However, feature selection cannot reveal the implicit structural information of the samples. In this article, the methods proposed by us combine both feature selection and feature extraction, called joint feature selection and extraction with sparse unsupervised projection (SUP) and graph optimization SUP (GOSUP). A constraint on the number of nonzero rows of the projection matrix is added, which ensures the sparsity of the projection matrix, and only the features corresponding to the nonzero rows of the projection matrix are selected for the feature extraction procedure. We invoke a newly proposed algorithm to tackle this constrained optimization problem. A new concept of ``purification matrix'' is invented, the use of which could better eliminate meaningless information of samples in subspace. The performance on several datasets verifies the effectiveness of the proposed method for data dimensionality reduction.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34531543

RESUMO

Graft-versus-host disease (GVHD) is a critical complication after allogeneic haematopoietic stem cell transplantation induced by genetic differences in donor-recipient pairs. Rigorous HLA matching has reduced GVHD, but severe GVHD still occurs. Minor histocompatibility antigens (mHAs) are another source of GVHD inducers. We designed a multi-mHA panel with 35 valid mHA loci and retrospectively analyzed 391 donor-recipient pairs with the anticipation of implementing mHA typing into clinical practice to optimize donor selection. Results showed the total mismatching in mHA loci in this panel, as well as mismatching in the GVH direction in unmatched-related recipients (UMRs) were 1.8 times and 1.3 times as those in matched-sibling recipients (MSRs) (p = 4.1e-4, p = 0.012, respectively). There was no significant association between mHA loci mismatching and grades II-IV acute GVHD (aGVHD), III-IV aGVHD, extensive chronic GVHD (cGVHD), or relapse in neither group. UMRs had an increased cumulative incidence of II-IV aGVHD (p = 0.002), but there was no statistical difference of the incidences in severe aGVHD or cGVHD (p = 0.093; p = 0.930). This is a preliminary study to explore GVHD risks brought by mHA loci mismatching in both unmatched-related recipients and matched-full-sibling recipients. Our results confirmed that stringent HLA matching is the key to reduce the risks for GVHD.

12.
Drug Des Devel Ther ; 15: 3697-3708, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34465981

RESUMO

Purpose: Puerarin (PR), a Chinese medicine rich in natural components, has been reported to display anti-fibrotic, antioxidant, anti-inflammatory and immunomodulatory properties. However, the protective mechanism of PR against unilateral ureteral obstruction (UUO)-mediated renal injury is not fully clarified. Therefore, the aim of this study was to investigate the effects of PR on UUO mice and its possible mechanisms. Methods: A total of 32 C57BL/6 mice were divided randomly into four groups (n=8): i) sham-operated group (Sham); ii) UUO group (UUO); iii) UUO + PR 50 mg/kg/day (UUO + PRL); and iv) UUO + PR 100 mg/kg/day (UUO + PRH). Continuous gavage administration for 14 days starting one week postoperatively, while the mice in Sham and UUO groups were given equal amounts of vehicle by the same means. All mice were then sacrificed and serum, 24-hour urine and tissue specimens were collected for renal function, histopathology, Western blot, immunohistochemistry. Results: Renal function and histopathology revealed that PR improved UUO-mediated renal dysfunction and partially reversed tubular injury and tubulointerstitial fibrosis. Additionally, according to the results of Western blot and immunohistochemistry, PR inhibited the expression of inflammatory factors including IL-1ß, IL-6, MCP-1 and ECM-related proteins including α-SMA, COL I and VIM. More importantly, the expression of fibrotic pathways TGF-ß1, Smad3, p-Smad3 and inflammatory pathways NF-κB p65, NF-κB p-p65, STAT3, p-STAT3 were inhibited to various extents under the PR treatment, while Smad7 was upregulated. Conclusion: These findings indicate that PR may inhibit the recruitment of inflammatory factors and extracellular matrix (ECM) deposition through the regulation of the NF-κB p65/STAT3 and TGFß1/Smads pathways, which alleviates the UUO-induced inflammatory and fibrotic response, thereby reversing renal injury.

13.
IEEE Trans Cybern ; PP2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34383658

RESUMO

Estimating 3-D hand pose estimation from a single depth image is important for human-computer interaction. Although depth-based 3-D hand pose estimation has made great progress in recent years, it is still difficult to deal with some complex scenes, especially the issues of serious self-occlusion and high self-similarity of fingers. Inspired by the fact that multipart context is critical to alleviate ambiguity, and constraint relations contained in the hand structure are important for the robust estimation, we attempt to explicitly model the correlations between different hand parts. In this article, we propose a pose-guided hierarchical graph convolution (PHG) module, which is embedded into the pixelwise regression framework to enhance the convolutional feature maps by exploring the complex dependencies between different hand parts. Specifically, the PHG module first extracts hierarchical fine-grained node features under the guidance of hand pose and then uses graph convolution to perform hierarchical message passing between nodes according to the hand structure. Finally, the enhanced node features are used to generate dynamic convolution kernels to generate hierarchical structure-aware feature maps. Our method achieves state-of-the-art performance or comparable performance with the state-of-the-art methods on five 3-D hand pose datasets: 1) HANDS 2019; 2) HANDS 2017; 3) NYU; 4) ICVL; and 5) MSRA.

14.
RSC Chem Biol ; 2(2): 289-305, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34423303

RESUMO

Like biomacromolecules, certain small molecules (e.g., aggregators) are able to self-assemble in aqueous phase to form nanoscale aggregates. Though it is well-established that the aggregates may interact with enzymes in vitro, the study of the biological activities of the assemblies of small molecules in cellular environment is only at its beginning. This review summarizes the recent progresses in exploring the biological functions of supramolecular assemblies of small molecules (SASMs). We first discuss the use of SASMs to inhibit pathogenic cells, such as cancer cells and bacteria. The use of SASMs to target different parts of cancer cells, such as pericellular space, cytosol, and subcellular organelles, and to combine with other bioactive entities (e.g., proteins and clinically used drugs), is particularly promising for addressing the challenge of acquired multidrug resistance in cancer therapy. Then, we describe the use of SASMs to sustain physiological functions of normal cells, that is, promoting cells proliferation and differentiation for tissue regeneration. After that, we show the use of SASMs as a basic tool to research cell behaviors, for instance, identifying the specific cells, improving enzyme probes, revealing membrane dynamics, enhancing molecular imaging, and mimicking context-dependent signaling. Finally, we give the outlook of the research of SASMs. We expect that this review, by highlighting the biological functions of SASMs, provides a starting point to explore the chemical biology of SASMs.

15.
Toxicol Appl Pharmacol ; 428: 115682, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34418406

RESUMO

Benzene, an important and widely used industrial chemical, is the cause of different types of blood disorders. However, the mechanisms of benzene-induced hematotoxicity are still unclear. This study aimed to explore the effects of benzene on metabolism, especially in amino acid metabolism, in human peripheral blood B lymphocyte cells (AHH-1 cells) treated with 1,4-benzoquinone (1,4-BQ) and in benzene-exposed population based on the un-targeted and targeted metabolomics platforms. The results showed that 1,4-BQ disturbed the metabolic activity, such as arginine biosynthesis, citrate cycle, glycine, serine, and threonine metabolism pathways, and significantly upregulated the ratio of sarcosine/glycine in vitro. Meanwhile, the targeted metabolomics further showed that the ratio of sarcosine/glycine was also increased in the benzene exposure population. Notably, the expression of glycine N-methyltransferase (GNMT), an enzyme catalyzing the transformation of glycine to sarcosine, was upregulated both in 1,4-BQ treated AHH-1 cells and benzene-exposed workers. These results imply that the glycine/GNMT/sarcosine axis was involved in benzene-induced hematotoxicity. Such evidence will help to develop a better understanding of the underlying mechanism of benzene-induced hematotoxicity at the level of amino acid metabolism.


Assuntos
Linfócitos B/metabolismo , Benzeno/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/sangue , Glicina N-Metiltransferase/sangue , Exposição Ocupacional/efeitos adversos , Sarcosina/sangue , Adulto , Linfócitos B/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino
16.
J Pharmacol Exp Ther ; 379(2): 147-155, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34400527

RESUMO

Intestinal mucositis resulting from 5-fluorouracil (5-FU)-based chemotherapy subjects patients to great pain and hampers cancer treatment progress. Puerarin, the major active ingredient in Pueraria lobata, exerts anti-inflammatory and antioxidative effects. However, whether puerarin has an effect on 5-FU-induced intestinal mucositis remains unknown. We established a mice model of intestinal mucositis through the intraperitoneal injection of 5-FU and then injected puerarin (50 and 100 mg/kg) intraperitoneally for 7 consecutive days. Routine parameters, such as body weight, food intake, and diarrheal incidence, were examined to evaluate the effects of puerarin on intestinal mucositis in mice. The intestinal barrier's functions were also evaluated by measuring the serum recovery of fluorescein isothiocyanate-4kD dextran in this study. The expression levels of inflammatory cytokines, inflammatory mediators, oxidative reactions, as well as apoptotic marker proteins were determined to elucidate the underlying mechanisms of puerarin on intestinal mucositis. The model mice presented symptoms and histopathological changes typical of 5-FU-induced intestinal mucositis. In addition to vigorous inflammatory reactions, oxidative reactions, and cell apoptosis, Janus kinase (JAK) was markedly activated. Puerarin decreased the expression levels of those of inflammatory mediators, oxidative reactions, and apoptosis-related proteins in 5-FU-induced mucositis by blocking the activation of JAK. Puerarin decreased inflammation, oxidative reactions, and apoptosis and protected intestinal barrier functions to ameliorate 5-FU-induced intestinal mucositis by inhibiting the activation of JAK. This study provides novel insights into the pathologic mechanisms of (and treatment alternatives for) 5-FU-induced intestinal mucositis. SIGNIFICANCE STATEMENT: This study reveals the mechanism responsible for the protective effects of puerarin in 5-fluorouracil-induced intestinal mucositis. Puerarin inhibits the activation of JAK, thereby suppressing inflammation, oxidative reactions, cell apoptosis, and protected intestinal barrier functions to ameliorate 5-FU-induced intestinal mucositis. Overall, our results suggest that puerarin can serve as a potential natural JAK inhibitor in the treatment of 5-FU-induced intestinal mucositis.

17.
Microb Pathog ; 159: 105119, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34339796

RESUMO

Staphylococcus aureus is an eminent and opportunistic human pathogen that can colonize in the intestines, skin tissue and perineal regions of the host and cause severe infectious diseases. The presence of complex regulatory network and existence of virulent gene expression along with tuning metabolism enables the S. aureus to adopt the diversity of environments. Two component system (TCS) is a widely distributed mechanism in S. aureus that permit it for changing gene expression profile in response of environment stimuli. TCS usually consist of transmembrane histidine kinase (HK) and cytosolic response regulator. S. aureus contains totally 16 conserved pairs of two component systems, involving in different signaling mechanisms. There is a connection among these regulatory circuits and they can easily have effect on each other's expression. This review has discussed five major types of TCS in S. aureus and covers the recent knowledge of their virulence gene expression. We can get more understanding towards staphylococcal pathogenicity by getting insights about gene regulatory pathways via TCS, which can further provide implications in vaccine formation and new ways for drug design to combat serious infections caused by S. aureus in humans.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Histidina Quinase/genética , Humanos , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Virulência
18.
ACS Appl Mater Interfaces ; 13(33): 38947-38958, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433245

RESUMO

Although dressing blood-contacting devices with robust and synergistic antibacterial and antithrombus properties has been explored for several decades, it still remains a great challenge. In order to endow materials with remarkable antibacterial and antithrombus abilities, a stable and antifouling hydrogel coating was developed via surface-initiated polymerization of sulfobetaine methacrylate and acrylic acid on a polymeric substrate followed by embedding of antimicrobial peptides (AMPs), including WR (sequence: WRWRWR-NH2) or Bac2A (sequence: RLARIVVIRVAR-NH2) AMPs. The chemical composition of the AMP-embedded hydrogel coating was determined through XPS, zeta potential, and SEM-EDS measurements. The AMP-embedded antifouling hydrogel coating showed not only good hemocompatibility but also excellent bactericidal and antiadhesion properties against Gram-positive and Gram-negative bacteria. Moreover, the hydrogel coating could protect the AMPs with long-term bioactivity and cover the positive charge of the dotted distributed AMPs, which in turn well retained the hemocompatibility and antifouling capacity of the bulk hydrogels. Furthermore, the microbiological results of animal experiments also verified the anti-infection performance in vivo. Histological and immunological data further indicated that the hydrogel coating had an excellent anti-inflammatory function. Therefore, the present study might provide a promising approach to prevent bacterial infections and thrombosis in clinical applications of blood-contacting devices and related implants.


Assuntos
Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Fibrinolíticos/química , Hidrogéis/química , Proteínas Citotóxicas Formadoras de Poros/química , Resinas Acrílicas/química , Antibacterianos/farmacologia , Bandagens , Sangue/metabolismo , Sobrevivência Celular , Materiais Revestidos Biocompatíveis/metabolismo , Eritrócitos , Fibrinolíticos/farmacologia , Hemólise , Humanos , Hidrogéis/metabolismo , Metacrilatos/química , Adesividade Plaquetária/efeitos dos fármacos , Polimerização , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Propriedades de Superfície
19.
J Clin Sleep Med ; 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34432630

RESUMO

STUDY OBJECTIVES: We assess the yearly seasonal, environmental effects on birth pattern in Chinese patients later diagnosed with narcolepsy and cataplexy, and explored if this effect persisted in patients with symptoms onset date before, following and after 2009 H1N1 pandemic. METHODS: A total of 1942 patients with birth data information and diagnosed narcolepsy with cataplexy were included in this study. The birth month and seasonal effect of 1064 patients born from 1970 to 2000 were compared to controls (n=2,028,714) from the general population. Furthermore, birth season effect in 1373 patients with definite disease onset month were compared among patients with onset date before (n=595), following (n=325), and after (n=453) H1N1 pandemic. RESULTS: Patients with narcolepsy and cataplexy had a significantly different seasonality from the general population (p = 0.027). The monthly distribution of birth month yielded a peak in November (odds ratio = 1.23 [95%CI, 1.01-1.49], p=0.042) and a trough in April (odds ratio = 0.68 [95%CI,0.52-0.88], p=0.004). No significant difference was observed in the birth month across patients with symptoms onset dates before, following and after the 2009 H1N1 pandemic (p=0.603). CONCLUSIONS: This reveal across many years of seasonal effect in Chinese narcolepsy cataplexy supports a role for early-life environmental influences on disease development.

20.
Viruses ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34452487

RESUMO

Hepatitis-hydropericardium syndrome (HHS) is caused by fowl adenovirus serotype 4 (FAdV-4) and has resulted in considerable economic losses to the poultry industry globally. FAdV-4 elicits apoptosis in host cells. Long noncoding RNAs (lncRNAs) have emerged as important regulatory RNAs with profound effects on various biological processes, including apoptosis. However, it remains unknown whether lncRNAs participate in FAdV-4-induced apoptosis. In this study, RNA sequencing was applied to determine the transcription of cellular lncRNA in leghorn male hepatocellular (LMH) cells infected with FAdV-4. Cellular RNA transcription analysis demonstrated that FAdV-4 infection elicited 1798 significantly differentially expressed (DE) lncRNAs in infected LMH cells at 24 h post-infection (hpi) compared to mock control infection. In addition, 2873 DE mRNAs were also found. Target prediction and analyses revealed that 775 DE lncRNAs whose 671 target mRNAs were among the DE mRNAs were involved in several signaling pathways, including the AMPK signaling pathway, p53 signaling pathway and insulin signaling pathway. From these 775 DE lncRNAs, we identified 71 DE lncRNAs related to apoptosis based on their target gene functions. Subsequently, lncRNA 54128 was selected from the 71 identified DE lncRNAs, and its role in FAdV-4-induced apoptosis was verified. LncRNA 54128 interference significantly suppressed the rate of apoptosis, which was accompanied by reduced BMP4 transcription levels. To the best of our knowledge, this is the first study to analyze host lncRNA transcription during FAdV-4 infection. Our findings provide a better understanding of host responses to FAdV-4 infection and provide new directions for understanding the potential association between lncRNAs and FAdV-4 pathogenesis.

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