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1.
Adv Mater ; : e2104107, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510578

RESUMO

Although excellent dielectric, piezoelectric, and pyroelectric properties matched with or even surpassing those of ferroelectric ceramics have been recently discovered in molecular ferroelectrics, their successful applications in devices are scarce. The fracture proneness of molecular ferroelectrics under mechanical loading precludes their applications as flexible sensors in bulk crystalline form. Here, self-powered flexible mechanical sensors prepared from the facile deposition of molecular ferroelectric [C(NH2 )3 ]ClO4 onto a porous polyurethane (PU) matrix are reported. [C(NH2 )3 ]ClO4 -PU is capable of detecting pressure of 3 Pa and strain of 1% that are hardly accessible by the state-of-the-art piezoelectric, triboelectric, and piezoresistive sensors, and presents the ability of sensing multimodal mechanical forces including compression, stretching, bending, shearing, and twisting with high cyclic stability. This scaling analysis corroborated with computational modeling provides detailed insights into the electro-mechanical coupling and establishes rules of engineering design and optimization for the hybrid sponges. Demonstrative applications of the [C(NH2 )3 ]ClO4 -PU array suggest potential uses in interactive electronics and robotic systems.

2.
Ecotoxicol Environ Saf ; 225: 112754, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34488145

RESUMO

Aflatoxin B1 (AFB1) is an unavoidable contaminant in animal feed and agricultural products. AFB1 has been found to impair the liver and kidney function of sheep. However, few data are available, which explain the toxic damage of AFB1 exposure on meat quality. In the study, male Dorper RAMS sheep (6-month-old) were orally administrated with AFB1 at the dose of 1 mg/kg body weight once. The body temperature, serum biochemistry, meat quality-related parameters, oxidation indicators in meat and serum, the mRNA expression of pro-inflammatory cytokines and anti-inflammatory, and microbiota composition of feces were measured 24 h after AFB1 exposure. The results showed that the body temperature was slightly increased, the mental state of mutton sheep was suppressed, and biochemical indicators were significantly changed after AFB1 exposure. AFB1 impaired mutton quality reflected by the structure of muscle fibers was changed, and increased muscle drip loss and lightness (L*), and decreased muscle redness (a*). Moreover, we found that AFB1 caused changes in the oxidative stress indicators T-SOD, T-AOC, MDA, GSH level, and GSH/GSSG ratio, and inflammation damage of mutton reflected by increasing pro-inflammatory TNF-α and reducing anti-inflammatory IL-10 mRNA levels, disrupts the secretion of inflammatory factors, and changed the composition of gut microbiota reflected by significantly increased Firmicutes/Bacteroidetes ratio and decreased the abundances of Butyrivibrio, which are related to the quality of the mutton. In summary, gut microbiota participates in AFB1 to damage mutton quality, which may be co-mediated by oxidative stress, inflammation, and gut microbiota.

3.
J Hazard Mater ; 423(Pt A): 127029, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34479086

RESUMO

Imidacloprid (IMI), as the most widely used neonicotinoid insecticide, poses a serious threat to the water ecosystem due to the inefficient elimination in the traditional water treatment. Chitosan (CTS)-stabilized biochar (BC)-supported Ag nanoparticles (CTS@AgBC) are applied to eliminate the IMI in the water treatment effectively. Batch experiments depict that the modification of BC by CTS and Ag nanoparticles remarkably improve its adsorption performance. The pseudo-second-order and Elovich models have good performance in simulating the adsorption processes of CTS@AgBC and BC. This indicates that the chemical adsorption on real surfaces plays the dominant role in the adsorption of IMI by CTS@AgBC and BC. In addition, the multihead attention (MHA)-based convolutional neural network (CNN) combined with the time-dependent Cox regression model are initially applied to predict and dissect the adsorption elimination processes of IMI by CTS@AgBC. The proposed MHA-CNN model achieves more accurate concentration prediction of IMI than traditional models. According to influence weights by MHA module, biochar category, pH, and treatment temperature are considered the three dominant environmental variables to determine the IMI elimination processes. This study provides insights into roles of environmental variables in the elimination of IMI by CTS@AgBC and the accurate prediction of IMI concentration.

4.
Front Immunol ; 12: 670616, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489929

RESUMO

Neutrophils are characterized by their heterogeneity. They fight against pathogens and are involved in tissue injury repair and immune system regulation. Neutrophils have an extremely short life span in the peripheral blood and undergo aging after being released from the bone marrow. The over-aggregation of aged neutrophils is associated with phenotypical and functional changes. Here, we aimed to investigate the dynamics of neutrophil aging and its relationship with T cell exhaustion in HIV-1 infection, as they are not well understood. In this study, we enrolled 23 treatment naïve (TN) patients, 23 individuals that had received antiretroviral therapy (ART), and 21 healthy controls (HC). In these cohorts, we measured the degree of neutrophil aging, and its possible correlation with T cell dysfunction. In TN patients, peripheral neutrophils showed a more distinct aging phenotype and were over-activated compared to those in ART-treated patients. The degree of neutrophil aging was positively correlated with HIV-1 RNA viral load and negatively correlated with CD4+ T cell count. Moreover, aged neutrophils had impaired reactive oxygen species (ROS) production after lipopolysaccharide (LPS) stimulation, and were characterized by increased PD-L1 and arginase-1 expression in a time-dependent manner. Aged neutrophils demonstrated an increased inhibition of IFN-γ and TNF-α secretion by CD8+ T cell compared to non-aged neutrophils. The inhibition effect could be partially reversed by blocking PD-L1 and arginase-1 in vitro, and LPS was identified as an important activator of neutrophil aging. These results provide evidence that dampening neutrophil aging may provide a novel approach to recover T cell dysfunction in patients with HIV-1 infection.

5.
Adv Sci (Weinh) ; : e2102777, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494718

RESUMO

There is no doubt that hydrogen energy can play significant role in promoting the development and progress of modern society. The utilization of hydrogen energy has developed rapidly, but it is far from the requirement of human. Therefore, it is very urgent to develop methodologies and technologies for efficient hydrogen production, especially high activity and durable electrocatalysts. Here a bimetallic oxide cluster on heterostructure of vanadium ruthenium oxides/graphdiyne (VRuOx /GDY) is reported. The unique acetylene-rich structure of graphdiyne achieves outstanding characteristics of electrocatalyst: i) controlled preparation of catalysts for achieving multiple-metal clusters; ii) regulation of catalyst composition and morphology for synthesizing high-performance catalysts; iii) highly active and durable hydrogen evolution reaction (HER) properties. The optimal porous electrocatalyst (VRu0.027 Ox /GDY) can deliver 10 mA cm-2 at low overpotentials of 13 and 12 mV together with robust long-term stability in alkaline and neutral media, respectively, which are much smaller than Pt/C. The results reveal that the synergism of different components can efficiently facilitate the electron/mass transport properties, reduce the energy barrier, and increase the active site number for high catalytic performances.

6.
Genome Med ; 13(1): 146, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493320

RESUMO

BACKGROUND: Epstein-Barr virus (EBV)-associated gastric carcinomas (EBVaGCs) present unique molecular signatures, but the tumorigenesis of EBVaGCs and the role EBV plays during this process remain poorly understood. METHODS: We applied whole-exome sequencing, EBV genome sequencing, and whole-genome bisulfite sequencing to multiple samples (n = 123) derived from the same patients (n = 25), which covered saliva samples and different histological stages from morphologically normal epithelial tissues to dysplasia and EBVaGCs. We compared the genomic landscape between EBVaGCs and their precursor lesions and traced the clonal evolution for each patient. We also analyzed genome sequences of EBV from samples of different histological types. Finally, the key molecular events promoting the tumor evolution were demonstrated by MTT, IC50, and colony formation assay in vitro experiments and in vivo xenograft experiments. RESULTS: Our analysis revealed increasing mutational burden and EBV load from normal tissues and low-grade dysplasia (LD) to high-grade dysplasia (HD) and EBVaGCs, and oncogenic amplifications occurred late in EBVaGCs. Interestingly, within each patient, EBVaGCs and HDs were monoclonal and harbored single-strain-originated EBV, but saliva or normal tissues/LDs had different EBV strains from that in EBVaGCs. Compared with precursor lesions, tumor cells showed incremental methylation in promotor regions, whereas EBV presented consistent hypermethylation. Dominant alterations targeting the PI3K-Akt and Wnt pathways were found in EBV-infected cells. The combinational inhibition of these two pathways in EBV-positive tumor cells confirmed their synergistic function. CONCLUSIONS: We portrayed the (epi) genomic evolution process of EBVaGCs, revealed the extensive genomic diversity of EBV between tumors and normal tissue sites, and demonstrated the synergistic activation of the PI3K and Wnt pathways in EBVaGCs, offering a new potential treatment strategy for this disease.

7.
Neuro Endocrinol Lett ; 42(5): 292-296, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34506092

RESUMO

OBJECTIVE: POEMS syndrome is a rare multisystemic disease, with a wide spectrum of clinical endocrinopathies. Patients with POEMS syndrome may present with one or more hormone disorders during the disease course, but such phenomenon has usually been underestimated. In this report, we analyzed the prevalence and clinical characteristics of endocrine abnormalities in a large Chinese cohort with POEMS syndrome. METHODS: This retrospective review was performed in patients with a definite diagnosis of POEMS syndrome who were hospitalized in our hospital between January 2000 and January 2020. The clinical data about endocrine abnormalities were extracted from their medical records and analyzed. RESULTS: This study comprised 136 patients (95 male, 41 female) with a median age of 48(40-56) years old. Endocrine abnormalities were frequent (127 cases, 93.38%) in patients with POEMS syndrome. The prevalence of single endocrinopathy and multiple endocrinopathies were 12.60% (16/127 cases) and 87.40% (111/127), respectively. The most frequent endocrinopathy was hypogonadism (98/136, 72.06%), followed by hypothyroidism (83/136, 61.03%), hypocalcemia (50/136, 36.76%), hyperprolactinemia (47/136, 34.56%), abnormal glucose metabolism (41/136, 30.15%) and adrenal insufficiency (41/136, 30.15%). In patients with multiple endocrinopathies, the prevalence of 2, 3, 4, 5, and 6 kinds of endocrine axes involved were 29.92% (38/127), 30.71% (39/127), 17.32% (22/127), 7.09% (9/127) and 2.36% (3/127), respectively. Such hormone disorders cause complex clinical presentations, including overt or subclinical situations. CONCLUSION: Endocrinopathy manifestations in POEMS syndrome are more frequent, and its clinical complicacy should be emphasized in differential diagnosis. For patients with a definite diagnosis of POEMS syndrome, an early and thorough endocrine evaluation should be performed.

8.
J Phys Chem Lett ; : 9011-9019, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34515494

RESUMO

The cubic-phase antimony trioxide (α-Sb2O3) is a room-temperature stable molecular crystal, composed of cage-like tetraantimony hexoxide (Sb4O6) molecules. Despite its versatile functionality, the van der Waals (vdW) bond-dominated nanomechanics is still unclear. Here, the bending plate-like linear behaviors of high-quality α-Sb2O3 nanoflakes were observed using the nanoindentation method. It is found that the cage-molecular crystal owns a very low in-plane Young's modulus of 14.9 ± 0.8 GPa and a remarkable maximum tensile strain of 6.0-8.8%, corresponding to a rupture strength of 0.89-1.31 GPa. Elucidated by the atomistic simulations, the compliant elastic modulus and the unexpectedly strong rupture strain are associated with the high-symmetry vdW bonding structure. The vdW nanomechanics is of fundamental and technological relevance to nanoelectronics.

9.
Neurol Ther ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34515953

RESUMO

INTRODUCTION: Corticospinal tract injury caused by direct hematoma compression and secondary damage induced from blood toxic substances might influence the outcomes in patients with intracerebral hemorrhage (ICH). This study aimed to evaluate the safety and efficacy of hematoma evacuation via image-guided para-corticospinal tract approach based on the protection of compressed or residual corticospinal tract. METHODS: Seventy-five patients with ICH who underwent the image-guided para-corticospinal tract approach were retrospectively collected into the surgery group. Diffusion tensor imaging or computed tomography angiography was performed to identify the relationship between important white matter tracts and hematoma. The neuronavigation system for the preoperative imaging data loaded was used to identify the location of the burr hole, insertion trajectory, and depth of insertion. Cortical entry points and insertion trajectories were kept parallel to the corticospinal tract route into the hematoma based on the protection of compressed or residual corticospinal tract. Hematoma was removed under the image-guided para-corticospinal tract approach. Seventy-five age-, sex-, hematoma site-, and volume-matched patients with ICH who underwent conservative treatment were selected as controls. Demographical, clinical, radiological, and treatment-related data were retrospectively analyzed. Functional outcome was evaluated by modified Rankin scale on day 90. RESULTS: A total of 150 patients with ICH were retrospectively enrolled. The median Glasgow coma scale (GCS) score on admission was 11 (IQR 8-13). Deep hematoma (thalamus and basal ganglion) was present in 86.7% (130 patients). The mean hematoma volume on admission was 47 ± 19 mL, and the postoperative hematoma volume was 11 ± 10 mL. A higher proportion of favorable outcome was observed in the surgery group than in conservative treatment group (32.0% versus 17.4%; p = 0.037). CONCLUSION: Hematoma evacuation via image-guided para-corticospinal tract approach based on the protection of compressed or residual corticospinal tract seems to be safer in patients with ICH with a relatively higher functional independence.

10.
J Hazard Mater ; 416: 126250, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492993

RESUMO

The research on the mechanisms and kinetics of radical oxidation in peracetic acid-based advanced oxidation processes was relatively limited. In this work, HO• and organic radicals mediated reactions of acetaminophen (ACT) were investigated, and the reactivities of important organic radicals (CH3COO• and CH3COOO•) were calculated. The results showed that initiated reaction rate constants of ACT are in the order: CH3COO• (5.44 × 1010 M-1 s-1) > HO• (7.07 × 109 M-1 s-1) > CH3O• (1.57 × 107 M-1 s-1) > CH3COOO• (3.65 × 105 M-1 s-1) >> •CH3 (5.17 × 102 M-1 s-1) > CH3C•O (1.17 × 102 M-1 s-1) > CH3OO• (11.80 M-1 s-1). HO•, CH3COO• and CH3COOO• play important roles in ACT degradation. CH3COO• is another important radical in the hydroxylation of aromatic compounds in addition to HO•. Reaction rate constants of CH3COO• and aromatic compounds are 1.40 × 106 - 6.25 × 1010 M-1 s-1 with addition as the dominant pathway. CH3COOO• has high reactivity to phenolate and aniline only among the studied aromatic compounds, and it was more selective than CH3COO•. CH3COO•-mediated hydroxylation of aromatic compounds could produce their hydroxylated products with higher toxicity.


Assuntos
Ácido Peracético , Poluentes Químicos da Água , Acetaminofen/toxicidade , Radical Hidroxila , Cinética , Oxirredução , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Signal Transduct Target Ther ; 6(1): 339, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34497264

RESUMO

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has placed a global public burden on health authorities. Although the virological characteristics and pathogenesis of COVID-19 has been largely clarified, there is currently no specific therapeutic measure. In severe cases, acute SARS-CoV-2 infection leads to immune disorders and damage to both the adaptive and innate immune responses. Having roles in immune regulation and regeneration, mesenchymal stem cells (MSCs) serving as a therapeutic option may regulate the over-activated inflammatory response and promote recovery of lung damage. Since the outbreak of the COVID-19 pandemic, a series of MSC-therapy clinical trials has been conducted. The findings indicate that MSC treatment not only significantly reduces lung damage, but also improves patient recovery with safety and good immune tolerance. Herein, we summarize the recent progress in MSC therapy for COVID-19 and highlight the challenges in the field.


Assuntos
COVID-19/terapia , Lesão Pulmonar/terapia , Pulmão/imunologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , SARS-CoV-2/imunologia , Animais , COVID-19/imunologia , COVID-19/patologia , Humanos , Pulmão/patologia , Pulmão/virologia , Lesão Pulmonar/imunologia , Lesão Pulmonar/virologia , Células-Tronco Mesenquimais/patologia
12.
mBio ; : e0233521, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34544279

RESUMO

Newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic with astonishing mortality and morbidity. The high replication and transmission of SARS-CoV-2 are remarkably distinct from those of previous closely related coronaviruses, and the underlying molecular mechanisms remain unclear. The innate immune defense is a physical barrier that restricts viral replication. We report here that the SARS-CoV-2 Nsp5 main protease targets RIG-I and mitochondrial antiviral signaling (MAVS) protein via two distinct mechanisms for inhibition. Specifically, Nsp5 cleaves off the 10 most-N-terminal amino acids from RIG-I and deprives it of the ability to activate MAVS, whereas Nsp5 promotes the ubiquitination and proteosome-mediated degradation of MAVS. As such, Nsp5 potently inhibits interferon (IFN) induction by double-stranded RNA (dsRNA) in an enzyme-dependent manner. A synthetic small-molecule inhibitor blunts the Nsp5-mediated destruction of cellular RIG-I and MAVS and processing of SARS-CoV-2 nonstructural proteins, thus restoring the innate immune response and impeding SARS-CoV-2 replication. This work offers new insight into the immune evasion strategy of SARS-CoV-2 and provides a potential antiviral agent to treat CoV disease 2019 (COVID-19) patients. IMPORTANCE The ongoing COVID-19 pandemic is caused by SARS-CoV-2, which is rapidly evolving with better transmissibility. Understanding the molecular basis of the SARS-CoV-2 interaction with host cells is of paramount significance, and development of antiviral agents provides new avenues to prevent and treat COVID-19 diseases. This study describes a molecular characterization of innate immune evasion mediated by the SARS-CoV-2 Nsp5 main protease and subsequent development of a small-molecule inhibitor.

13.
BMC Genomics ; 22(1): 674, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544387

RESUMO

BACKGROUND: Plant non-specific lipid transfer proteins (nsLTPs), a group of small, basic ubiquitous proteins to participate in lipid transfer, cuticle formation and stress response, are involved in the regulation of plant growth and development. To date, although the nsLTP gene family of barley (Hordeum vulgare L.) has been preliminarily identified, it is still unclear in the recently completed genome database of barley and Qingke, and its transcriptional profiling under abiotic stress has not been elucidated as well. RESULTS: We identified 40 barley nsLTP (HvLTP) genes through a strict screening strategy based on the latest barley genome and 35 Qingke nsLTP (HtLTP) orthologues using blastp, and these LTP genes were divided into four types (1, 2, D and G). At the same time, a comprehensive analysis of the physical and chemical characteristics, homology alignment, conserved motifs, gene structure and evolution of HvLTPs and HtLTPs further supported their similar nsLTP characteristics and classification. The genomic location of HvLTPs and HtLTPs showed that these genes were unevenly distributed, and obvious HvLTP and HtLTP gene clusters were found on the 7 chromosomes including six pairs of tandem repeats and one pair of segment repeats in the barley genome, indicating that these genes may be co-evolutionary and co-regulated. A spatial expression analysis showed that most HvLTPs and HtLTPs had different tissue-specific expression patterns. Moreover, the upstream cis-element analysis of HvLTPs and HtLTPs showed that there were many different stress-related transcriptional regulatory elements, and the expression pattern of HvLTPs and HtLTPs under abiotic stress also indicated that numerous HvLTP and HtLTP genes were related to the abiotic stress response. Taken together, these results may be due to the differences in promoters rather than by genes themselves resulting in different expression patterns under abiotic stress. CONCLUSION: Due to a stringent screening and comprehensive analysis of the nsLTP gene family in barley and Qingke and its expression profile under abiotic stress, this study can be considered a useful source for the future studies of nsLTP genes in either barley or Qingke or for comparisons of different plant species.

14.
Chem Commun (Camb) ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34546227

RESUMO

Ultrafine ternary carbide Co6W6C@C nanoparticles (NPs) were successfully synthesized and these NPs exhibited high catalytic activities for the hydrazine oxidation reaction (HzOR) under alkaline conditions. In a practical O2-hydrazine fuel cell test, its peak power density reached 203 mW cm-2, a value superior to that of the state-of-the-art commercial Pt/C catalyst.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34490742

RESUMO

The sigma (σ)-hole effect has emerged as a promising tool to construct novel architectures endowed with new properties. A simple yet effective strategy for the generation of monofluoromethyl radical is a continuing challenge within the synthetic community. Flu-oromethylphosphonium salts are easily available, air- and thermally-stable, as well as simple-to-handle. Herein, we report the ability of σ-hole effect to facilitate the visible light-triggered photolysis of phosphonium iodide salts, a charge transfer complex, selectively giving fluoromethyl radicals. The usefulness and versatility of this new protocol are demonstrated through the mono-, di-, and trifluoro-methylation of a variety of alkenes.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34465614

RESUMO

BACKGROUND AND OBJECTIVES: To assess the molecular landscape of B-cell subpopulations across different compartments in patients with neuromyelitis optica spectrum disorder (NMOSD). METHODS: We performed B-cell transcriptomic profiles via single-cell RNA sequencing across CSF, blood, and bone marrow in patients with NMOSD. RESULTS: Across the tissue types tested, 4 major subpopulations of B cells with distinct signatures were identified: naive B cells, memory B cells, age-associated B cells, and antibody-secreting cells (ASCs). NMOSD B cells show proinflammatory activity and increased expression of chemokine receptor genes (CXCR3 and CXCR4). Circulating B cells display an increase of antigen presentation markers (CD40 and CD83), as well as activation signatures (FOS, CD69, and JUN). In contrast, the bone marrow B-cell population contains a large ASC fraction with increased oxidative and metabolic activity reflected by COX genes and ATP synthase genes. Typically, NMOSD B cells become hyperresponsive to type I interferon, which facilitates B-cell maturation and anti-aquaporin-4 autoantibody production. The pool of ASCs in blood and CSF were significantly elevated in NMOSD. Both CD19- and CD19+ ASCs could be ablated by tocilizumab, but not rituximab treatment in NMOSD. DISCUSSION: B cells are compartmentally fine tuned toward autoreactivity in NMOSD and become hyperreactive to type I interferon. Inhibition of type I interferon pathway may provide a new therapeutic avenue for NMOSD.

17.
Adv Sci (Weinh) ; : e2102539, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473423

RESUMO

The stress-response strategy is one of the nature's greatest developments, enabling animals and plants to respond quickly to environmental stimuli. One example is the stress-response strategy of the Venus flytrap, which enables such a delicate plant to perceive and prey on insects at an imperceptible speed by their soft terminal lobes. Here, inspired by this unique stress-response strategy, a soft gripper that aims at the challenges of high-speed dynamic grasping tasks is presented. The gripper, called high-speed soft gripper (HSG), is based on two basic design concepts. One is a snap-through instability that enables the HSG to sense the mechanical stimuli and actuating instantly. The other one is the spider-inspired pneumatic-powered control system that makes the trigger process repeatable and controllable. Utilizing the stress-response strategy, the HSG can accomplish high-speed sensing and grasping and handle a dynamic grasping task like catching a thrown baseball. Whereas soft machines typically exhibit slow locomotion speed and low manipulation strength for the intrinsic limitations of soft materials, the exploration of the stress-response strategy in this study can help pave the way for designing a new generation of practical high-speed soft robots.

18.
Adv Healthc Mater ; : e2101247, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473428

RESUMO

Clinical wound management remains a major challenge due to massive bleeding, bacterial infection, and difficult wound healing after tissue trauma. To simultaneously address these issues, composite polymer sponges for accelerating drug-resistant bacterial infected wound healing are fabricated by facilely mixing sodium polyacrylate (PAAS), double quaternary ammonium salts-conjugated chitosan (QAS-CS), and collagen (COL) in aqueous solution, followed by lyophilization. Composite sponges (PAAS/QAS-CS/COL, PQC) show highly porous microstructures (porosity ≈90%) with moderate compress modulus (≈0.3 MPa), tensile strength (0.004 MPa), and high swelling ratio (≈3500%). Importantly, PQC sponge demonstrates superior hemostasis ability over commercially available CS sponge by inducing rapid hemagglutination, and exhibits significantly better antibacterial activity against both methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli by destroying cell membrane and causing the leakage of bioactive components such as potassium ion and ß-galactosidase from treated bacterial. Furthermore, PQC sponge can efficiently promote cell proliferation. Significantly, the sponge greatly expedites the regeneration of MRSA-infected full-thickness skin wound in rabbit by successfully eradicating bacterial infection, and reducing inflammation. PQC sponge also improves both early angiogenesis and blood vessel maturation at the wound site. Overall, this multifunctional sponge is a promising wound dressing for clinical use and holds great potential for rapid clinical translation.

19.
Emerg Microbes Infect ; : 1-31, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520320

RESUMO

AbstractHuman adenovirus types 4 (HAdV4) and 7 (HAdV7) often lead to severe respiratory diseases and occur epidemically in children, adults, immune deficiency patients, and other groups, leading to mild or severe symptoms and even death. However, no licensed adenovirus vaccine has been approved in the market for general use. E3 genes of adenovirus are generally considered nonessential for virulence and replication; however, a few studies have demonstrated that the products of these genes are also functional. In this study, most of the E3 genes were deleted, and two E3-deleted recombinant adenoviruses (ΔE3-rAdVs) were constructed as components of the vaccine. After E3 deletion, the replication efficiencies and cytopathogenicity of ΔE3-rAdVs were reduced, indicating that ΔE3-rAdVs were attenuated after E3 genes deletion. Furthermore, single immunization with live-attenuated bivalent vaccine candidate protects mice against challenge with wild-type human adenovirus types 4 and 7, respectively. Vaccinated mice demonstrated remarkably decreased viral loads in the lungs and less lung pathology compared to the control animals. Taken together, our study confirms the possibility of the two live-attenuated viruses as a vaccine for clinic use and illustrates a novel strategy for the construction of an adenovirus vaccine.

20.
Int J Cancer ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520576

RESUMO

Elevated serum uric acid (SUA) levels have been previously reported to play a role in multiple types of cancers. However, epidemiological studies evaluating SUA levels and colorectal cancer risk remain sparse. This cohort study included 444,462 participants between the ages of 40 and 69 years from the UK Biobank, followed-up from 2006 to 2010. Multivariable adjusted Cox regression models were used to estimate hazard ratios (HRs). During a mean follow-up of 6.6 years, 2,033 and 855 cases of colon and rectal cancers, respectively, were diagnosed. The multivariable-adjusted HRs for risks of colon cancer in the lowest uric acid categories (≤3.5 mg/dL) compared with the reference groups were 1.31 (95% confidence interval [CI]: 0.75-2.29) in males and 1.26 (95% CI: 1.03-1.55) in females. The HRs in the highest uric acid groups (>8.4 mg/dL) were 1.16 (95% CI: 0.83-1.63) in males and 2.00 (95% CI: 1.02-3.92) in females. The corresponding HRs of rectal cancer in the lowest uric acid groups compared with the reference group were 2.21 (95% CI: 1.15-4.23) in males and 0.98 (95% CI: 0.66-1.45) in females. The HRs in the highest uric acid groups were 1.35 (95% CI: 0.82-2.23) in males and 3.81 (95% CI: 1.38-10.56) in females. In conclusion, SUA showed a U-shaped association with colon cancer risk in both male and female populations. The same pattern was observed in male patients with rectal cancer. However, SUA levels were positively associated with occurrence of rectal cancer in female subjects. This article is protected by copyright. All rights reserved.

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