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1.
Sci Rep ; 10(1): 7635, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32376987

RESUMO

Proteolytic cleavage of influenza A virus (IAV) hemagglutinin by host proteases is crucial for virus infectivity and spread. The transmembrane serine protease TMPRSS2 was previously identified as the essential protease that can cleave hemagglutinin of many subtypes of influenza virus and spike protein of coronavirus. Herein, we found that a guanine rich tract, capable of forming intramolecular G-quadruplex in the presence of potassium ions, in the promoter region of human TMPRSS2 gene was quite important for gene transcriptional activity, hence affecting its function. Furthermore, 7 new synthesized benzoselenoxanthene analogues were found to enable stabilizing such G-quadruplex. More importantly, compounds can down-regulate TMPRSS2 gene expression, especially endogenous TMPRSS2 protein levels, and consequently suppress influenza A virus propagation in vitro. Our results provide a new strategy for anti-influenza A virus infection by small molecules targeting the TMPRSS2 gene G-quadruplex and thus inhibiting TMPRSS2 expression, which is valuable for developing small molecule drugs against influenza A virus and also may be a potential candidate as anti- SARS-CoV-2 (Severe Acute Respiratory Syndrome CoV 2) lead molecules.


Assuntos
Vírus da Influenza A/crescimento & desenvolvimento , Compostos Organosselênicos , Serina Endopeptidases/genética , Linhagem Celular , Pegada de DNA , Descoberta de Drogas , Quadruplex G , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Vírus da Influenza A/fisiologia , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Regiões Promotoras Genéticas , Transcrição Genética
2.
Pediatr Hematol Oncol ; : 1-7, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32364426

RESUMO

Spina bifida has been reported to co-occur with pediatric cancer, but comprehensive evaluations remained elusive. We investigated this co-occurrence in two large, population-based studies in Taiwan (N = 1900 cancer cases, 2,077,137 controls) and Denmark (N = 5508 cases, 137,700 controls). Analyses in Denmark were restricted to the period before prenatal diagnostics became available (2004) and pregnancy terminations of fetuses with birth defects became more common. Using national patient and cancer registries, we linked spina bifida and cancer diagnoses among cases and non-cases. The risk of spina bifida among all cancer cases was increased and similar in Denmark [odds ratio (OR)=8.4, 95% confidence interval (CI) 5.1-13.8] and Taiwan (OR = 8.5, 95% CI 4.0-17.8), particularly for central nervous system (CNS) tumors (Denmark: OR = 16.3, 95% CI 8.1-33.0; Taiwan: OR = 26.6, 95% CI 8.5, 83.1), including benign CNS tumors (Denmark: OR = 41.5, 95% CI 21.2, 81.4). These findings suggest the need for comprehensive investigation of shared risk factors in the link between spina bifida and pediatric cancer.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32394635

RESUMO

Radical pimers are the simplest and most important models for studying charge transfer processes, and they provide deep insights into π-stacked organic materials. Notably, radical pimer systems with magnetic bi- or multistability may have important applications in switchable materials, thermal sensors and information storage media. However, no such systems have been reported. Here, we describe a new pimer consisting of neutral N -(n-propyl) benzene triimide ([BTI-3C]) and its anionic radical ([BTI-3C] -• ), which exhibits rare magnetic multistability. The crystalline pimer was easily synthesized by reduction of BTI-3C with cobaltocene (CoCp 2 ). The transition occurs with a 27 K-width thermal hysteresis loop in the range of 170-220 K, accompanied by a smaller 25 K-width loop at 220-242 K. The magnetic multistabilty was attributed to the slippage of the π-stacked BTI backbones and the entropy-driven conformational isomerization of the side propyl chains in the crystalline state during temperature variation. Our research demonstrated an unprecedented radical pimer showing magnetic multistability. The high diversity of the substituents on BTI provides great possibilities for designing multifunctional materials.

4.
Complement Ther Clin Pract ; 39: 101130, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32379643

RESUMO

INTRODUCTION: To systematically review and meta-analyze the efficacy of moxibustion in treating patients with chronic low back pain (CLBP). METHODS: A systematic search of the Cochrane Library, Web of Science, PubMed, Embase, EBSCO, CBM, Wanfang, CNKI and VIP (until November, 2019) was used to identify studies reporting pain intensity (VAS or NRS), disability (ODI or RMDQ), JOA score, and quality of life (SF-36) in patients with CLBP. Study selection, data extraction was performed critically and independently by two reviewers. Cochrane criteria for risk of bias was used to assess the methodological quality of the trials. The Grading of Recommendations Assessment, Development, and Evaluation Methodology (GRADE) was applied to test the quality of evidence from the quantitative analysis. RESULTS: Ten RCTs, including 987 patients, met the inclusion criteria. Moxibustion had a superior effect on VAS score when compared with western medicine [RR = -1.69, 95%CI(-2.40, -0.98), p < 0.00001] and acupuncture [RR = -0.47, 95%CI(-0.92, -0.02), p=0.04], but it failed to do so when compared with core stability training [RR = -0.41, 95%CI(-0.87, 0.05), p=0.08]. The result showed that moxibustion plus other active treatments (including western medicine, massage, acupuncture and core stability training) had better effects on low back pain relief compared with active treatments alone. Moxibustion showed favourable effects on disability [SMD = -3.80, 95%CI (-5.49, -2.11), p < 0.0001], JOA score [MD = 4.10, 95%CI(2.30, 5.90), p < 0.00001], and SF-36 score [MD = 13.41, 95%CI(9.68, 17.14), p < 0.00001]. The evidence level of the results from the ten studies was determined to be very low to low. CONCLUSIONS: It is difficult to draw firm conclusions that moxibustion is an effective intervention for treating CLBP due to the small sample size of eligible trails and the high risk of bias among the available articles. Rigorously designed large-scale RCTs are required to further confirm the results in this review.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32434102

RESUMO

Changes in cellular metabolism accompany tumor therapeutic resistance. Metabolite concentrations specifically reflect the cellular state. Glutathione (GSH) metabolism maintains the redox homeostasis while also confers therapeutic resistance to cancer cells. However, analytical methods for studying GSH metabolism rely on high-resolution-based untargeted metabolomics. Since the aim of untargeted metabolomics studies is covering as much metabolites as possible, these methods lack sensitivity for simultaneous analysis of intracellular GSH-related metabolites with different polarities and structures. In this study, based on cultured lung cancer cells, we described a rapid, robust and sensitive ultra-performance liquid chromatography-triple quadrupole tandem mass spectrographic method (UPLC-QQQ-MS/MS) to simultaneously quantify a repertoire of GSH-related metabolites, including GSH, GSSG, glycine, cysteine, glutamine, glutamate, cystine, γ-glutamyl-cysteine and cysteinyl-glycine. This method avoided the use of derivatization and/or ion-pairing reagents and was validated according to United States Food and Drug Administration (US FDA) criteria. The lower limit of quantification was determined to be 0.5-100 ng/mL with lower limits of detection at 0.14-10.07 ng/mL. The intra- and inter-day precision values for all the analytes were <15% CV, and the accuracy ranged from 85.4% to 114% at three levels of quality control. This method combined simple preparation with rapid analytical procedure (8 min), allowed for high-throughput analysis of GSH metabolism in basic and therapeutic treatment conditions within cultured cells. Our data showed a significant alteration of GSH metabolism in two independent resistant cells compared to sensitive cells. This method monitored the impact of molecularly targeted drugs on GSH metabolism within lung cancer cells and therefore helped identifying potential metabolic vulnerability for the therapeutic resistance in lung cancer.

6.
Oecologia ; 193(1): 155-165, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32356013

RESUMO

Soil resource heterogeneity can affect plant growth and competitive ability. However, little is known about how soil resource heterogeneity affects competitive interactions between invasive and native plants. We conducted an experiment with an invasive clonal plant Alternanthera philoxeroides and a coexisting native one Alternanthera sessilis. The experiment was a randomized design with three factors, i.e. two species (A. philoxeroides and A. sessilis), two interspecific competition treatments (with and without) and five soil treatments (three homogeneous treatments and two small-scale heterogeneous treatments consisting of two patches of 10 cm × 15 cm and with different initial planting positions). Irrespective of competition, increasing soil resource availability increased the growth of A. philoxeroides. Increasing soil resource availability also increased the growth of A. sessilis without competition, but had no impact with competition. Irrespective of competition, soil resource heterogeneity increased biomass and ramet production of A. philoxeroides, and such effects were independent of initial planting position. For A. sessilis, however, soil resource heterogeneity only increased ramet production when the initial plant was grown in the low-resource patch without competition. Our results suggest that both high soil resource availability and small-scale soil resource heterogeneity can increase the relative competitive ability of the invasive plant A. philoxeroides when grown with its native congener A. sessilis. These findings may partly explain the invasion success of this clonal species in area with high soil resource availability and heterogeneity caused by e.g. nitrogen deposition, fertilization and disturbance.


Assuntos
Amaranthaceae , Solo , Biomassa , Espécies Introduzidas , Plantas
7.
Eur Respir J ; 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32430429

RESUMO

BACKGROUND: Timely diagnosis of SARS-CoV-2 infection is a prerequisite for treatment and prevention. The serology characteristics and complement diagnosis value of the antibody test to RNA test need to be demonstrated. METHOD: Serial sera of 80 patients with PCR-confirmed COVID-19 were collected at the First Affiliated Hospital of Zhejiang University, China. Total antibody (Ab), IgM and IgG antibodies against SARS-CoV-2 were detected, and the antibody dynamics during the infection were described. RESULTS: The seroconversion rates for Ab, IgM and IgG were 98.8%, 93.8% and 93.8%, respectively. The first detectible serology marker was Ab, followed by IgM and IgG, with a median seroconversion time of 15, 18 and 20 days post exposure (d.p.e) or 9, 10 and 12 days post onset (d.p.o), respectively. The antibody levels increased rapidly beginning at 6 d.p.o. and were accompanied by a decline in viral load. For patients in the early stage of illness (0-7 d.p.o), Ab showed the highest sensitivity (64.1%) compared to IgM and IgG (33.3% for both, p<0.001). The sensitivities of Ab, IgM and IgG increased to 100%, 96.7% and 93.3% 2 weeks later, respectively. When the same antibody type was detected, no significant difference was observed between enzyme-linked immunosorbent assays and other forms of immunoassays. CONCLUSIONS: A typical acute antibody response is induced during SARS-CoV-2 infection. Serology testing provides an important complement to RNA testing in the later stages of illness for pathogenic specific diagnosis and helpful information to evaluate the adapted immunity status of patients.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32432467

RESUMO

Neural system is a multi-functional perceptual learning system. Our brain can perceive different kinds of information to form senses, including touch, sight, hearing, etc. Mimicking such perceptual learning systems is critical for neuromorphic platform applications. Here, an artificial tactile perceptual neuron is realized by utilizing E-skin with oxide neuromorphic transistors, and this artificial tactile perceptual neuron successfully simulates biological tactile afferent nerves. Firstly, the E-skin device is constructed using microstructured PDMS membranes coated with Ag/ITO layers, exhibiting good sensitivities of ~2.1 kPa-1 and fast response time of tens of milliseconds. Then, the chitosan-based electrolyte-gated ITO neuromorphic transistor is fabricated and exhibits high performance and synaptic responses. Finally, the integrated artificial tactile perceptual neuron demonstrates pressure excitatory postsynaptic current (EPSC) and paired-pulse facilitation (PPF). The artificial tactile perceptual neuron is featured with low energy consumption as low as ~0.7 nJ. Moreover, it can mimic acute and chronic pain and nociceptive characteristics of allodynia and hyperalgesia in biological nociceptors. Interestingly, the artificial tactile perceptual neuron can employ "Morse code" pressure interpreting scheme. This simple and low-cost approach has excellent potential for applications including but not limited to intelligent humanoid robots and replacement neuroprosthetics.

9.
Enzyme Microb Technol ; 136: 109537, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32331719

RESUMO

Given their special action mechanisms and structural simplicity, L-amino acid ligases (Lals) are considered to be desirable tools for the catalytic biosynthesis of dipeptides. Ywf E (BacD) was the first Lal identified and was shown to be involved in the biosynthesis of a potent antibacterial, bacilysin, since then, various novel Lals have been discovered. Each Lal has different substrate spectra and is capable of synthesizing different dipeptides. Owning to their great potentials for producing bioactive dipeptides of industrial importance, in this review, recent developments of Lals are discussed, including their structures, action mechanisms, applications and the advantages and disadvantages of different Lals. In addition, protein engineering of Lals to improve their substrate specificity and catalytic performance is also discussed.

10.
JAMA Ophthalmol ; 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32239185

RESUMO

Importance: Rates of visual field (VF) progression vary among patients with glaucoma. Knowing the rate of progression of individual patients would allow appropriately aggressive therapy for patients with high rates of visual loss and protect those with low rates from unnecessary therapy. Objective: To compare 3 pointwise methods of estimating the rate of VF progression in glaucoma. Design, Setting, and Participants: This retrospective, observational cohort study included 729 eyes of 567 consecutive patients with primary open-angle glaucoma who had at least 6 reliable VFs and at least 3 years of follow-up. One hundred seventy-six patients (257 eyes) were treated at a tertiary glaucoma center; in addition, data were collected from 391 participants (472 eyes) in the Advanced Glaucoma Intervention Study. Data were collected from May 1988 to November 2004 and analyzed from October 2018 to February 2019. Exposures: Estimates of VF progression were measured with guided progression analysis (GPA), pointwise linear regression (PLR), and the glaucoma rate index (GRI). A subgroup analysis was performed in a subset of patients with likely VF progression and likely VF stability. Main Outcomes and Measures: Proportion of VF series detected as progressing, estimates of false-positive proportions, time to detect progression, and agreement among measures. Results: Among the 567 patients included in the analysis, mean (SD) age was 65.6 (9.7) years, 300 (52.9%) were female, and 295 (52.0%) were white. The median baseline mean deviation was -6.7 (interquartile range [IQR], -11.6 to -3.5) dB; the median follow-up time, 8.9 (IQR, 7.3-10.4) years. The proportion of eyes labeled as progressing was 27.7% according to the GPA, 33.5% according to the PLR, and 52.9% according to the GRI; pairwise differences for GRI vs PLR were 20% (95% CI, 17%-23%); for GRI vs GPA, 25% (95% CI, 22%-29%); and for PLR vs GPA, 6% (95% CI, 3%-9%; P < .001 for all comparisons, McNemar test). The shortest median time to progression was with the GRI (8.8 [IQR, 2.4-10.5 years), compared with the GPA and PLR (both >16 years). The hazard ratio of VF progression for GRI vs PLR (reference) was 11.3 (95% CI, 9.2-13.7); for GRI vs GPA (reference), 18.1 (95% CI, 14.5-22.6); and for PLR vs GPA (reference), 1.5 (95% CI, 1.3-1.9; P < .001 for all comparisons, Cox proportional hazards regression). These results held in the subgroup with likely progression; the proportions of progressing eyes were 73.7% (115 of 156) for GPA, 81.4% (127 of 156) for PLR, and 92.9% (145 of 156) for GRI. Pairwise difference for GRI vs PLR was 11.5% (95% CI, 7.4%-17.6%; P < .001, McNemar test); for GRI vs GPA, 19.2% (95% CI, 12.6%-26.4%; P < .001, McNemar test); and for PLR vs GPA, 7.7% (95% CI, 0.3%-15.7%; P = .08, McNemar test). Conclusions and Relevance: These results suggest GRI can detect long-term VF progression in glaucoma earlier than PLR or GPA. Validation with prospective designs may strengthen the generalizability and value of this method.

11.
Braz J Med Biol Res ; 53(5): e8457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348428

RESUMO

The objective of this study was to investigate whether the conjugation of gold nanoparticles (GNPs) to 5-aminolevulinic acid (5-ALA) could enhance the anti-tumor efficiency of photodynamic therapy (PDT) in epidermoid carcinoma cells. The mRNA and protein expression levels were determined by quantitative real-time PCR and western blot, respectively. Cell viability, apoptosis, invasion, and migration were determined by MTT assay, flow cytometry, transwell invasion assay, and migration assay, respectively. Singlet oxygen generation was detected by the singlet oxygen sensor green reagent assay. Our results showed that PDT with 5-ALA and GNPs-conjugated 5-ALA (5-ALA-GNPs) significantly suppressed cell viability, increased cell apoptosis and singlet oxygen generation in both HaCat and A431 cells, and PDT with 5-ALA and 5-ALA-GNPs had more profound effects in A431 cells than that in HaCat cells. More importantly, 5-ALA-GNPs treatment potentiated the effects of PDT on cell viability, cell apoptosis, and singlet oxygen generation in A431 cells compared to 5-ALA treatment. Further in vitro assays showed that PDT with 5-ALA-GNPs significantly decreased expression of STAT3 and Bcl-2 and increased expression of Bax in A431 cells compared with PDT with 5-ALA. In addition, 5-ALA-GNPs treatment enhanced the inhibitory effects of PDT on cell invasion and migration and Wnt/ß-catenin signaling activities in A431 cells compared to 5-ALA treatment. In conclusion, our results suggested that GNPs conjugated to 5-ALA significantly enhanced the anti-tumor efficacy of PDT in A431 cells, which may represent a better strategy to improve the outcomes of patients with cutaneous squamous cell carcinoma.

13.
Chemosphere ; 254: 126717, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32339795

RESUMO

Pantropical spotted dolphins are apex predators and have a long lifespan, which makes them susceptible to chemical pollutants such as polybrominated diphenyl ethers (PBDEs), which are associated with immunotoxicity in wildlife. However, the effects of PBDEs and their mechanism of immunotoxicity in dolphins is largely unknown. Previously, we established fibroblast cell lines obtained from pantropical spotted dolphins (PSD-LWHT) as an in vitro model for assessing the toxicological implications of chemical pollutants in dolphins. In this study, we used the novel immortalized fibroblast cell line to explore the potential immune stimulation effect of PBDEs via prostaglandins signaling pathways to better understand the immunotoxicity pathway of PBDEs in dolphins. BDE-47, -100, and -209 exposure generally resulted in an increase in inflammatory cytokine expression, PGE2 levels, and COX-2 gene expression but BDE-209 resulted in a suppression in IL-10 production. Both protein and mRNA expression of COX-2 and PTGES increased significantly following exposure to the PBDEs. The results suggested BDE-100 and -209 increased prostaglandin E2 (PGE2) production via increased expression of COX-2 and PTGES expression. Only BDE-100 increased expression level of the prostaglandin E2 receptor EP4 while BDE-47 and BDE-209 decreased its expression. This probably explained why suppressive effect on the expression level of anti-inflammatory cytokines were only found in exposure with BDE-47 and BDE-209 rather than BDE-100. The results showed that PBDEs stimulate innate immune response by triggering PGE2-EPs-cAMP-cytokines signaling.

14.
Chemistry ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32329538

RESUMO

The energetically viable fabrication of stable and highly efficient solid acid catalysts is one of the key steps in the large-scale transformation processes of biomass resources. Herein, we report the covalent modification of the classical Dawson polyoxometalate (POMs) with sulphonic acids (-SO3H) by grafting the sulfonic acid groups on the POM's surface followed by oxidation of (3-Mercaptopropyl)trimethoxysilane. The acidity of TBA6-P2W17-SO3H (TBA = tetrabutyl ammonium) has been demonstrated using 31P.NMR, clearly indicating the presence of strong Brønsted acid sites. The presence of TBA counterions renders the solid acid catalyst as a promising candidate for phase transfer catalytic processes. The TBA6-P2W17-SO3H shows remarkable activity and selectivity, excellent stability and great substrate compatibility for the esterification of free fatty acids (FFA) with methanol and conversion into biodiesel at 70 °C with >98% conversion of oleic acid in 20 min. The excellent catalytic performance can be attributed to the formation of a catalytically active emulsion, which results in a uniform catalytic behavior during the reaction leading to efficient interaction between the substrate and the active sites of the catalyst. Most importantly, the catalyst can be easily recovered and reused without any loss of its catalytic activity due to its excellent phase transfer properties. This work offers an efficient and cost-effective strategy for large scale biomass conversion applications.

15.
Chem Commun (Camb) ; 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32329764

RESUMO

A heterostructured CoAl-layered double hydroxide/MoS2 nanocomposite photocatalyst (CoAl-LDH/MoS2) for CO2 photoreduction was prepared by simple electrostatic interactions. The syngas ratio (H2 : CO) was precisely tuned from 1.3 : 1 to 15 : 1 by altering only the catalyst concentration in the photocatalytic CO2 reduction system under visible light (λ > 400 nm). Interestingly, a rather high evolution rate can be obtained from CO2 photoreduction to CO up to 4575 µmol g-1 h-1 even under irradiation above 500 nm.

17.
BMC Microbiol ; 20(1): 75, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245419

RESUMO

BACKGROUND: Oral microbiota is not only important for maintaining oral health but also plays a role in various oral diseases. However, studies regarding microbiome changes in oral lichen planus (OLP) are very limited. To the best of our knowledge, there has been only two studies investigating salivary microbiome changes in OLP. Therefore, the purpose of this study was to identify the characteristic microbial profile in the saliva of OLP patients, with or without erosive lesions, and compare that with recurrent aphthous ulcer (RAU), a common oral immunological disorder that also shows multiple erosive/ulcerative lesions. Whole saliva samples were collected from 20 patients with OLP (erosive E, n = 10 and non-erosive NE, n = 10), 10 patients with RAU (U) and 10 healthy controls (C). DNA was extracted from the saliva samples, and the 16S rDNA gene V4 hypervariable region was analyzed using Illumina sequencing. RESULTS: We obtained 4949 operational taxonomic units (OTUs) from the V4 region in all saliva samples. Community composition analysis showed a clear decreased relative abundance of genera Streptococcus and Sphingomonas in saliva from RAU patients when compared to the other three groups. Relative abundance of Lautropia and Gemella were higher in E group, whereas relative abundance of Haemophilus and Neisseria were higher in NE group when compared to C group. Abiotrophia and Oribacterium were higher in OLP (combining E and NE groups), while Eikenella and Aggregatibacter were lower when compared to C group. There was statistically significance in α-diversity between E and RAU groups(p < 0.05). Significant differences in ß-diversity were detected in bacteria between E and C; NE and C; as well as E and NE groups. The LDA effect size algorithm identified the g_Haemophilus might be the potential biomarker in NE group. CONCLUSIONS: We found that salivary microbiome in erosive OLP was significantly different from that found in RAU; and these changes may be related to the underlying disease process rather than presence of ulcerative/erosive lesions clinically. In addition, our findings in bacterial relative abundance in OLP were significantly different from the previously reported findings, which points to the need for further research in salivary microbiome of OLP.

18.
Mater Sci Eng C Mater Biol Appl ; 111: 110767, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279789

RESUMO

Corneal and conjunctival infections are common ocular diseases, sometimes, causing severe and refractory drug-resistant bacteria infections. Fungal keratitis is a leading cause for blindness and traditional medical treatment is unsatisfactory. Thus, there is an urge to develop a new therapy to deal with these cases. In this study, we developed surface modified poly(lactic acid) (PLA) electrospun nanofibrous membranes (EFMs) with silver nanoparticles (AgNPs) and cellulose nanofibrils (CNF) as scaffolds for cell proliferation and antimicrobial application. The AgNPs with a very low content (below 0.1%) were easily anchored on the surface of PLA EFMs by CNF, which endowed the scaffold with hydrophilicity and antibacterial ability. The in-vitro cell co-culture experiments showed that the scaffold had great biocompatibility to ocular epithelial cells, especially the scaffolds coated by CNF, which significantly proliferated cells. Furthermore, the antibacterial activity could reach >95% inhibiting Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) due to the implantation of AgNPs, and the antifungal activity was also outstanding with most of the Fusarium spp. inhibited. Hence, the developed PLA EFMs with CNF and AgNPs are promising ocular bandages to promote cell proliferation and kill infectious pathogens, exhibiting potential applications in ocular wound healing in the future.

19.
BMJ ; 369: m1443, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317267

RESUMO

OBJECTIVE: To evaluate viral loads at different stages of disease progression in patients infected with the 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the first four months of the epidemic in Zhejiang province, China. DESIGN: Retrospective cohort study. SETTING: A designated hospital for patients with covid-19 in Zhejiang province, China. PARTICIPANTS: 96 consecutively admitted patients with laboratory confirmed SARS-CoV-2 infection: 22 with mild disease and 74 with severe disease. Data were collected from 19 January 2020 to 20 March 2020. MAIN OUTCOME MEASURES: Ribonucleic acid (RNA) viral load measured in respiratory, stool, serum, and urine samples. Cycle threshold values, a measure of nucleic acid concentration, were plotted onto the standard curve constructed on the basis of the standard product. Epidemiological, clinical, and laboratory characteristics and treatment and outcomes data were obtained through data collection forms from electronic medical records, and the relation between clinical data and disease severity was analysed. RESULTS: 3497 respiratory, stool, serum, and urine samples were collected from patients after admission and evaluated for SARS-CoV-2 RNA viral load. Infection was confirmed in all patients by testing sputum and saliva samples. RNA was detected in the stool of 55 (59%) patients and in the serum of 39 (41%) patients. The urine sample from one patient was positive for SARS-CoV-2. The median duration of virus in stool (22 days, interquartile range 17-31 days) was significantly longer than in respiratory (18 days, 13-29 days; P=0.02) and serum samples (16 days, 11-21 days; P<0.001). The median duration of virus in the respiratory samples of patients with severe disease (21 days, 14-30 days) was significantly longer than in patients with mild disease (14 days, 10-21 days; P=0.04). In the mild group, the viral loads peaked in respiratory samples in the second week from disease onset, whereas viral load continued to be high during the third week in the severe group. Virus duration was longer in patients older than 60 years and in male patients. CONCLUSION: The duration of SARS-CoV-2 is significantly longer in stool samples than in respiratory and serum samples, highlighting the need to strengthen the management of stool samples in the prevention and control of the epidemic, and the virus persists longer with higher load and peaks later in the respiratory tissue of patients with severe disease.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Adulto , China , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Carga Viral
20.
Artigo em Inglês | MEDLINE | ID: mdl-32311745

RESUMO

BACKGROUND: Preoperative computed tomography (CT)-guided localization has been shown to significantly improve lung nodule video-assisted thoracoscopic surgery (VATS)-based wedge resection technical success rates. However, at present, there was insufficient research regarding the optimal approaches to localization of these nodules prior to resection. We aimed to compare the relative clinical efficacy of preoperative CT-guided methylene blue and coil-based lung nodule localization. METHODS: In total, 91 patients with lung nodules were subjected to either CT-guided methylene blue (n = 34) or coil (n = 57) localization and VATS resection from January 2014 to December 2018. We compared baseline data, localization-associated complication rates, as well as the technical success of localization and resection between these two groups of patients. RESULTS: In total, 42 lung nodules in 34 patients underwent methylene blue localization, with associated localization and wedge resection technical success rates of 97.6 and 97.6%, respectively. A total of 71 lung nodules in 57 patients underwent coil localization, with associated localization and wedge resection technical success rates of 94.4 and 97.2%, respectively. There were no significant differences in technical success rates of localization or wedge resection between these groups (p = 0.416 and 1.000, respectively). The coil group sustained a longer duration between localization and VATS relative to the methylene blue group (13.2 vs. 2.5 hours, p = 0.003). CONCLUSION: Both methylene blue and coil localization can be safely and effectively implemented for conducting the diagnostic wedge resection of lung nodules. The coil-based approach is compatible with a longer period of time between localization and VATS procedures.

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