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1.
Nucleic Acids Res ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021674

RESUMO

Group II introns are the putative progenitors of nuclear spliceosomal introns and use the same two-step splicing pathway. In the cell, the intron RNA forms a ribonucleoprotein (RNP) complex with the intron-encoded protein (IEP), which is essential for splicing. Although structures of spliced group II intron RNAs and RNP complexes have been characterized, structural insights into the splicing process remain enigmatic due to lack of pre-catalytic structural models. Here, we report two cryo-EM structures of endogenously produced group II intron RNPs trapped in their pre-catalytic state. Comparison of the catalytically activated precursor RNP to its previously reported spliced counterpart allowed identification of key structural rearrangements accompanying splicing, including a remodeled active site and engagement of the exons. Importantly, altered RNA-protein interactions were observed upon splicing among the RNP complexes. Furthermore, analysis of the catalytically inert precursor RNP demonstrated the structural impact of the formation of the active site on RNP architecture. Taken together, our results not only fill a gap in understanding the structural basis of IEP-assisted group II intron splicing, but also provide parallels to evolutionarily related spliceosomal splicing.

2.
BMC Surg ; 20(1): 233, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046007

RESUMO

BACKGROUND: For ventral hernia, endoscopic sublay repair (ESR) may overcome the disadvantages of open sublay and laparoscopic intraperitoneal onlay mesh repair. This retrospective study presents the preliminary multicenter results of ESR from China. The feasibility, safety, and effectiveness of ESR were evaluated; its surgical points and indications were summarized. METHODS: The study reviewed 156 ventral hernia patients planned to perform with ESR in ten hospitals between March 2016 and July 2019. Patient demographics, hernia characteristics, operative variables, and surgical results were recorded and analyzed. RESULTS: ESR was performed successfully in 153 patients, 135 with totally extraperitoneal sublay (TES) and 18 with transabdominal sublay (TAS). In 19 patients, TES was performed with the total visceral sac separation (TVS) technique, in which the space separation is carried out along the peritoneum, avoiding damage to the aponeurotic structure. Endoscopic transversus abdominis release (eTAR) was required in 17.0% of patients, and only 18.3% of patients required permanent mesh fixation. The median operative time was 135 min. Most patients had mild pain and resume eating soon after operation. No severe intraoperative complications occurred. Bleeding in the extraperitoneal space occurred in two patients and was stopped by nonsurgical treatment. Seroma and chronic pain were observed in 5.23 and 3.07% of patients. One recurrence occurred after TAS repair for an umbilical hernia. CONCLUSION: ESR is feasible, safe, and effective for treating ventral hernias when surgeons get the relevant surgical skills, such as the technique of "partition breaking," TVS, and eTAR. Small-to-medium ventral hernias are the major indications.

3.
Respir Res ; 21(1): 241, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32957997

RESUMO

BACKGROUND: Patients with cardiovascular comorbidities are at high risk of poor outcome from COVID-19. However, how the burden (number) of vascular risk factors influences the risk of severe COVID-19 disease remains unresolved. Our aim was to investigate the association of severe COVID-19 illness with vascular risk factor burden. METHODS: We included 164 (61.8 ± 13.6 years) patients with COVID-19 in this retrospective study. We compared the difference in clinical characteristics, laboratory findings and chest computed tomography (CT) findings between patients with severe and non-severe COVID-19 illness. We evaluated the association between the number of vascular risk factors and the development of severe COVID-19 disease, using a Cox regression model. RESULTS: Sixteen (9.8%) patients had no vascular risk factors; 38 (23.2%) had 1; 58 (35.4%) had 2; 34 (20.7%) had 3; and 18 (10.9%) had ≥4 risk factors. Twenty-nine patients (17.7%) experienced severe COVID-19 disease with a median (14 [7-27] days) duration between onset to developing severe COVID-19 disease, an event rate of 4.47 per 1000-patient days (95%CI 3.10-6.43). Kaplan-Meier curves showed a gradual increase in the risk of severe COVID-19 illness (log-rank P < 0.001) stratified by the number of vascular risk factors. After adjustment for age, sex, and comorbidities as potential confounders, vascular risk factor burden remained associated with an increasing risk of severe COVID-19 illness. CONCLUSIONS: Patients with increasing vascular risk factor burden have an increasing risk of severe COVID-19 disease, and this population might benefit from specific COVID-19 prevention (e.g., self-isolation) and early hospital treatment measures.


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Doenças Vasculares/epidemiologia , Idoso , Betacoronavirus/patogenicidade , China/epidemiologia , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Doenças Vasculares/diagnóstico
4.
Plant Mol Biol ; 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876816

RESUMO

KEY MESSAGE: This research provides comprehensive insight into the molecular networks and molecular mechanisms underlying D. officinale flower development. Flowers are complex reproductive organs and play a crucial role in plant propagation, while also providing sustenance for insects and natural bioactive metabolites for humans. However, knowledge about gene regulation and floral metabolomes in flowers is limited. In this study, we used an important orchid species (Dendrobium officinale), whose flowers can be used to make herbal tea, to perform transcriptome sequencing and metabolic profiling of early- and medium-stage flower buds, as well as opened flowers, to provide comprehensive insight into the molecular mechanisms underlying flower development. A total of 8019 differentially expressed genes (DEGs) and 239 differentiated metabolites were found. The transcription factors that were identified and analyzed belong exclusively to the MIKC-type MADS-box proteins and auxin responsive factors that are known to be involved in flower development. The expression of genes involved in chlorophyll and carotenoid biosynthesis strongly matched the metabolite accumulation patterns. The genes related to flavonoid and polysaccharide biosynthesis were active during flower development. Interestingly, indole-3-acetic acid and abscisic acid, whose trend of accumulation was inverse during flower development, may play an important role in this process. Collectively, the identification of DEGs and differentiated metabolites could help to illustrate the regulatory networks and molecular mechanisms important for flower development in this orchid.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32865669

RESUMO

The prevalence and outcomes of patients who had re-activation of coronavirus disease 2019 (COVID-19) after discharge remain poorly understood. We included 126 consecutively confirmed cases of COVID-19 with 2-month follow-up data after discharge in this retrospective study. The upper respiratory specimen using a reverse-transcription polymerase chain reaction test of three patients (71 years [60-76]) were positive within 11-20 days after their discharge, with an event rate of 19.8 (95%CI 2.60-42.1) per 1,000,000 patient-days. Moreover, all re-positive patients were asymptomatic. Our findings suggest that few recovered patients may still be virus carriers even after reaching the discharge criteria.

6.
J Cell Mol Med ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32969198

RESUMO

The persistent transactivation of epidermal growth factor receptor (EGFR) causes subsequent activation of the TGF-ß/Smad3 pathway, which is closely associated with fibrosis and cell proliferation in diabetic nephropathy (DN), but the exact mechanism of persistent EGFR transactivation in DN remains unclear. ARAP1, a susceptibility gene for type 2 diabetes, can regulate the endocytosis and ubiquitination of membrane receptors, but the effect of ARAP1 and its natural antisense long non-coding RNA (lncRNA), ARAP1-AS2, on the ubiquitination of EGFR in DN is not clear. In this study, we verified that the expression of ARAP1 and ARAP1-AS2 was significantly up-regulated in high glucose-induced human proximal tubular epithelial cells (HK-2 cells). Moreover, we found that overexpression or knockdown of ARAP1-AS2 could regulate fibrosis and HK-2 cell proliferation through EGFR/TGF-ß/Smad3 signalling. RNA pulldown assays revealed that ARAP1-AS2 directly interacts with ARAP1. Coimmunoprecipitation, dual-immunofluorescence and ubiquitination assays showed that ARAP1 may maintain persistent EGFR activation by reducing EGFR ubiquitination through competing with Cbl for CIN85 binding. Taken together, our results suggest that the lncRNA ARAP1-AS2 may promote high glucose-induced proximal tubular cell injury via persistent EGFR/TGF-ß/Smad3 pathway activation by interacting with ARAP1.

7.
Mol Genet Genomic Med ; : e1501, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32959514

RESUMO

BACKGROUND: 21-Hydroxylase deficiency (21-OHD) caused by the CYP21A2 gene mutations is the most common form of congenital adrenal hyperplasia. It is an autosomal recessive disorder that results in defective synthesis of cortisol and aldosterone. The incidences of various CYP21A2 gene mutations and the genotype-phenotype correlations vary among different populations. MATERIALS AND METHODS: The clinical and molecular data of 22 patients were analyzed in this study. All patients were recruited from the neonatal intensive care unit. Locus-specific polymerase chain reaction and Sanger sequencing were applied to identify gene micro-conversions, and multiplex ligation-dependent probe amplification was used to detect large fragment deletions/conversions. Then, the genotypes were categorized in to Null, A, B, C, and D groups to analyze the relationships between genotypes and phenotypes. RESULTS: All 22 patients were classified into classic salt wasting form of 21-OHD. Molecular defects were detected in 44 alleles (100%). Micro-conversion mutation IVS2-13A/C>G (70.5%) is most common in our cohort, followed by large gene deletions and conversions (22.7%). The other mutations present were p.R357 W (4.5%) and E6 Cluster (2.3%). Genotypes of 22 patients (100%) were consistent with the predictive phenotypes. CONCLUSION: In this study, we identified the mutation spectrum of CYP21A2 gene in Chinese patients, especially the younger age cohort in pediatrics. Micro-conversions were the most popular mutations. Moreover, the genotypes and phenotypes were well correlated in this cohort of salt wasting 21-OHD recruited from neonatal intensive care unit.

8.
J Hematol Oncol ; 13(1): 119, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883331

RESUMO

Tumor metastasis accounts for the majority of cancer-related deaths; it is therefore important to develop preclinical models that faithfully recapitulate disease progression. Here, we generated paired organoids derived from primary tumors and matched liver metastases in the same colorectal cancer (CRC) patients. Despite the fact that paired organoids exhibit comparable gene expression and cell morphology, organoids from metastatic lesions demonstrate more aggressive phenotypes, tumorigenesis, and metastatic capacity than those from primary lesions. Transcriptional analyses of the paired organoids reveal signature genes and pathways altered during the progression of CRC, including SOX2. Further study shows that inducible knockdown of SOX2 attenuated invasion, proliferation, and liver metastasis outgrowth. Taken together, we use patient-derived paired primary and metastatic cancer organoids to model CRC metastasis and illustrate that SOX2 is associated with CRC progression and may serve as a potential prognostic biomarker and therapeutic target of CRC.

9.
Medicine (Baltimore) ; 99(39): e22322, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991441

RESUMO

RATIONALE: Bronchiolar adenoma (BA) is a newly designated rare entity of the lung, including both the currently designated ciliated muconodular papillary tumor (CMPT) and so-called non-classic CMPT. The most prominent histological feature of BAs is the bilayered cell structures composed of the continuous basal cell layer and the luminal layer which consists of different proportion of mucinous cells, ciliated cells, Clara cells and/or type II pneumocytes. BA purely covered by mucinous cells without other components in the luminal layer has never been reported. PATIENT CONCERNS: An 82-year-old female patient was detected a 0.8 cm ground glass nodule in the left lower lobe of the lung. DIAGNOSES: The serum levels of tumor markers were normal. INTERVENTIONS: The patient underwent a segmentectomy of the left lower lobe. OUTCOMES: The postoperative pathological diagnosis was BA. Molecular analysis revealed that the tumor harbored ALK rearrangement and BRAF mutations simultaneously. There was no recurrence in 17 months of follow-up. LESSONS: BA can be lined only by mucinous cells, without any cuboidal and/or ciliated cells in the surface layer. This sets a dangerous pitfall in differentiation diagnosis with invasive mucinous adenocarcinoma especially during intraoperative frozen pathological diagnosis.


Assuntos
Adenoma/metabolismo , Bronquíolos/patologia , Neoplasias Pulmonares/patologia , Biologia Molecular/métodos , Adenoma/cirurgia , Assistência ao Convalescente , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/metabolismo , Biomarcadores Tumorais/sangue , Feminino , Humanos , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Pneumonectomia/métodos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Resultado do Tratamento
10.
Int J Surg ; 83: 125-130, 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32931979

RESUMO

BACKGROUND: The use of intraoperative neuromonitoring (IONM) for visual identification of recurrent laryngeal nerve (RLN) has decreased the rates of RLN injury (RLNI) during thyroid surgery. However, little attention has been paid to RLNI near the nerve entry point (NEP), where most injuries occur. The aim of this study was to determine the mechanism of RLNI near the NEP and to describe the recovery of nerve function. METHODS: Patients undergoing thyroid surgery were analyzed to identify true loss of signal (LOS) by IONM. Follow-up for vocal cord palsy (VCP) was confirmed by a postoperative laryngoscopy. The risk factors for RLNI, the type of RLNI, the prevalence of VCP and the time for VCP recovery were all recorded and analyzed. RESULTS: We analyzed 3582 at-risk nerves in 2257 surgical patients. The overall rate of RLNI near the NEP in at-risk nerves was 3.2%. RLNI was more likely to occur in nerves with extralaryngeal bifurcation (p = 0.013). The distribution of RLNI types, in order of frequency, was traction (52.6%; n = 61), compression (38.8%; n = 45), thermal (7.8%; n = 9), and nerve transection (0.9%; n = 1). Complete recovery from VCP was documented in 93.1% (n = 108) of RLNI. CONCLUSION: Patients with a bifurcated RLN were at a higher risk of RLNI near the NEP than those without bifurcation. Traction and compression injuries occurred most frequently, but would eventually recover. Excessive stretching of the thyroid lobe played a role in RLNIs near the NEP.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32894445

RESUMO

The regeneration of EDTA-FeII is a key step in electrobiofilm reduction-integrated systems for NOx removal from industrial boiler flue gas. The current and carbon sources are proposed to be the two crucial electron donors for EDTA-FeII regeneration. These parameters strongly influence the reactivity of EDTA-FeII-generated products in the system. Therefore, their effects on EDTA-FeII-NO and EDTA-FeIII reduction and the EDTA-FeII generation mechanism were studied. The results showed that the electrobiofilm method has obvious advantages over biological or electrochemical methods used alone for EDTA-FeII regeneration. Under the optimal conditions at a current of 22.9A m-3 net cathode chamber, the rate of EDTA-FeII regeneration reached 98.35%. The glucose concentration is the primary factor influencing the reduction of both EDTA-FeII-NO and EDTA-FeIII, while the current significantly promotes both processes. Comparison of the Km values of the two substrates indicated that microbial activity was crucial to the reduction of EDTA-FeII-NO, but the biological reduction of EDTA-FeIII had a competitive influence on EDTA-FeII-NO reduction, which limited the abundance and effectiveness of the bacteria responsible for EDTA-FeII-NO reduction in the electrobiofilm system.

12.
J Am Chem Soc ; 142(41): 17557-17563, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32954726

RESUMO

When the size of nanomaterials reduces to the sub-1 nm scale, benefiting from size-induced mechanical flexibility and nearly 100% exposure of surface atoms, some new physical and chemical phenomena emerge, such as flexibility and polymer-like rheology. However, how to design and synthesize superflexible and high-performance hybrid sub-1 nm superstructures remains a great challenge. Herein, by incorporating four kinds of tungsten-based polyoxometallate (POM) clusters into the synthetic system of MoO3 during the nucleation step, we successfully prepared four kinds of super-flexible hybrid sub-1 nm nanobelt superstructures (HSNSs). Molecular dynamics (MD) simulations demonstrated that POM clusters interacted with MoO3 molecules and co-assembled into stable HSNSs, which could shrink, bend, curl and twist randomly in space and show super-flexible properties. These four kinds of MoO3-POM HSNSs not only performed high photothermal conversion but also showed excellent catalytic activity in the oxidation of thioethers at room temperature. This work paves the way for synthesis and broader applications of super-flexible cluster-inorganic-materials-based HSNSs.

13.
Genome Biol ; 21(1): 222, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859244

RESUMO

We present a base editing system, in which base editors are attached to different sites of sgRNA scaffold (sgBE). Each independent sgBE has its own specific editing pattern for a given target site. Among tested sgBEs, sgBE-SL4, in which deaminase is attached to the last stem-loop of sgRNA, yields the highest editing efficiency in the window several nucleotides next to the one edited by BE3. sgBE enables the simultaneous editing of adenine and cytosine. Finally, in order to facilitate in vivo base editing, we extend our sgBE system to an AAV-compatible Cas9, SaCas9 (Staphylococcus aureus), and observe robust base editing.

14.
Chin J Integr Med ; 26(8): 577-582, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32761337

RESUMO

BACKGROUND: The incidence of cognitive impairment (CI) is gradually increasing, which has attracted more attention from medical researchers worldwide. Definitive mechanisms of pathogenesis remain elusive, and there are few medications that have been proven effective for CI. The utilization of Chinese herbal medicine has shown positive therapeutic effects for a broad spectrum of diseases, including CI. OBJECTIVE: The purpose of this study is to evaluate the safety and efficacy of Guilingji Capsules (GLJC, ) in treating mild-to-moderate CI with Shen (Kidney) and marrow deficiency syndrome. METHODS: This is a randomized, double-blind, positive-controlled, multicenter clinical trial with a noninferiority design that included 348 participants randomly divided into an experimental arm and an active comparator arm. Individuals in the experimental arm (174 cases) took 0.6 g of GLJC once a day and 19.2 mg of Gingko biloba extract mimetic 3 times a day. Individuals in the active comparator arm (174 cases) took 0.6 g of GLJC mimetic once a day and 19.2 mg of Gingko biloba extract in tablet form 3 times a day. The intervention period included two sessions over 24 weeks. The primary outcome be the effectiveness of GLJC on cognitive improvement after 24 weeks of treatment, which was defined as an increase in the Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) Scale. The secondary outcomes were improvement in independence, daily living ability, and Chinese medicine (CM) syndrome, which were measured with the Alzheimer's disease Rating Scale-Cognitive Project (ADAS-Cog), Clinical Dementia Rating (CDR) Total Score, Activities of Daily Living (ADL) Total Score and the Chinese Medicine Symptom Scale (CM-SS), respectively. Serum acetylcholine, acetylcholinesterase, bax and bcl-2 were monitored to explore the mechanism of GLJC on CI. In addition, safety measures, including vital signs, electrocardiography, laboratory indicators (full blood count, kidney and liver function tests, routine urine test and routine stool test) and adverse events, were also recorded. DISCUSSION: The purpose of this trial is to evaluate the efficacy and safety of GLJC in patients with mild-to-moderate CI with kidney and marrow deficiency syndrome. If successful, the results would provide a viable treatment for patients with mild-to-moderate CI. (Clinical Trials.gov. ID: NCT03647384. Registered on 23 August 2018).

15.
Bioinformatics ; 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32745209

RESUMO

SUMMARY: Structural visualization and analysis are fundamental to explore macromolecular functions. Here we present a novel integrative web-based virtual reality (VR) system - VRmol, to visualize and study molecular structures in an immersive virtual environment. Importantly, it is integrated with multiple online databases and able to couple structure studies with associated genomic variations and drug information in a visual interface by cloud-based drug docking. VRmol thus can serve as an integrative platform to aid structure-based translational research and drug design. AVAILABILITY AND IMPLEMENTATION: VRmol is freely available (https://VRmol.net), with detailed manual and tutorial (https://VRmol.net/docs). The code of VRmol is available as open source under the MIT license at http://github.com/kuixu/VRmol. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

16.
Chin Med J (Engl) ; 133(16): 1952-1960, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32826459

RESUMO

BACKGROUND: Electrical stimulation has been recommended as an effective therapy to prevent muscle atrophy after nerve injury. However, the effect of electrical stimulation on the proliferation of satellite cells in denervated muscles has not yet been fully elucidated. This study was aimed to evaluate the changes in satellite cell proliferation after electrical stimulation in nerve injury and to determine whether these changes are related to the restoration of myofiber cross-section area (CSA). METHODS: Sciatic nerve crush injury was performed in 48 male Sprague-Dawley rats. In half (24/48) of the rats, the gastrocnemius was electrically stimulated transcutaneously on a daily basis after injury, while the other half were not stimulated. Another group of 24 male Sprague-Dawley rats were used as sham operation controls without injury or stimulation. The rats were euthanized 2, 4, and 6 weeks later. After 5-bromo-2'-deoxyuridine (BrdU) labeling, the gastrocnemia were harvested for the detection of paired box protein 7 (Pax7), BrdU, myofiber CSA, and myonuclei number per fiber. All data were analyzed using two-way analysis of variance and Bonferroni post-hoc test. RESULTS: The percentages of Pax7-positive nuclei (10.81 ±â€Š0.56%) and BrdU-positive nuclei (34.29 ±â€Š3.87%) in stimulated muscles were significantly higher compared to those in non-stimulated muscles (2.58 ±â€Š0.33% and 1.30 ±â€Š0.09%, respectively, Bonferroni t = 15.91 and 18.14, P < 0.05). The numbers of myonuclei per fiber (2.19 ±â€Š0.24) and myofiber CSA (1906.86 ±â€Š116.51 µm) were also increased in the stimulated muscles (Bonferroni t = 3.57 and 2.73, P < 0.05), and both were positively correlated with the Pax7-positive satellite cell content (R = 0.52 and 0.60, P < 0.01). There was no significant difference in the ratio of myofiber CSA/myonuclei number per fiber among the three groups. CONCLUSIONS: Our results indicate that satellite cell proliferation is promoted by electrical stimulation after nerve injury, which may be correlated with an increase in myonuclei number and myofiber CSA.

17.
Am J Emerg Med ; 38(9): 1807-1815, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32738474

RESUMO

INTRODUCTION AND METHODS: Early and accurate risk stratification of patients with atrial fibrillation (AF) in the emergency department (ED) could aid the physician in determining a timely treatment strategy appropriate to the severity of disease. We conducted a retrospective review of 243 adult patients who presented to a tertiary ED with AF in 2017. Primary outcome studied was 30-day adverse event (a composite outcome of repeat visit to the ED, cardiovascular complications, and all-cause mortality). Secondary outcome studied was 90-day all-cause mortality. We compared the performance of the RED-AF, AFTER and CHA2DS2-VASc score by plotting receiver operating characteristic (ROC) curves and estimating the areas under curves (AUC), and assessed the potential to further improve the tools with their incorporation of new variables. RESULTS: Existing scoring tools had poor predictive value for 30-day adverse events, with the RED-AF score performing comparatively better, followed by the AFTER and CHA2DS2-VASc score. All scores performed collectively better to predict 90-day mortality, with the AFTER score performing the best, followed by the RED-AF and CHA2DS2-VASc score. By incorporating heart rate at initial presentation to the ED as a variable into the AFTER Score, we generated a Modified AFTER Score with superior predictive performance above existing scores for 90-day mortality. CONCLUSION: Existing scores collectively performed poorly to predict 30-day adverse outcomes, but the AFTER and Modified AFTER score showed good predictive value for 90-day mortality. Further studies should be done to validate their use in guiding clinician's disposition of patients with AF in the ED.

18.
Sci Prog ; 103(3): 36850420940891, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32686995

RESUMO

A negative stiffness mechanism consisting of a spring and cylinder is proposed, and a grounded dynamic vibration absorber is designed based on a quasi-zero stiffness vibration isolator to constitute the vibration isolator with a vibration absorber system. The range of parameters for attaining zero stiffness is derived from static analysis. The dynamic analysis of the vibration isolator with a vibration absorber system is carried out by a multiscale method, and the amplitude-frequency response equation of the system is obtained. The influence of different system parameters on the amplitude-frequency response is analyzed. The amplitude-frequency response of the quasi-zero stiffness vibration isolator is compared with that of the vibration isolator with a vibration absorber, and the linear and nonlinear analytical solutions of the vibration isolator with a vibration absorber system are also compared. The results show that the designed vibration isolator with a vibration absorber is an ideal choice for low-frequency vibration isolation, with no large resonance peak throughout the system and significantly improved reliability of the system.

19.
Can J Physiol Pharmacol ; 98(8): 522-530, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32729719

RESUMO

Acute lung injury (ALI), a disease with a high mortality rate, is a noncardiogenic pulmonary inflammatory response and characterized by damage to the pulmonary system. In this study, we explored the mechanism of the occurrence and development of ALI. It was firstly found that miR-138-5p could inhibit the expression of sirtuin1 (SIRT1), and we further demonstrated that miR-138-5p targets directly SIRT1 through the luciferase assay, while the latter negatively regulated the expression of NF-κB. A549 cells were treated with lipopolysaccharide in vitro to simulate ALI cells and induce ALI in the model mice. The results showed that inhibiting the expression of miR-138-5p could effectively increase the viability of damaged cells, promote cell proliferation, reduce apoptosis, inhibit the inflammatory response, reduce oxidative stress, and then relieve ALI symptoms. Collectively, our results suggested that miR-138-5p can inhibit SIRT1 expression and indirectly activate the NF-κB signaling pathway, thus regulating the development of ALI.

20.
Appl Opt ; 59(20): 5983-5988, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32672751

RESUMO

In this paper, we propose a method to increase the field of view (FOV) in a holographic display. Different from the traditional method, a large-sized computer-generated hologram (CGH) is generated, and a holographic function screen is used in the proposed method. The CGH is formed by superposition of interference fringes. The diffraction boundary angle of the interferogram is set to be equal to the maximum diffraction angle of the reconstructed light. In the holographic reconstruction, three spatial light modulators (SLMs) arranged side by side in a linear configuration are used to load the CGH. The holographic functional screen is used for eliminating the seams between the SLMs and further enlarging the diffraction light. With the proposed method, the reconstructed light after each image point is expanded, so that the FOV can be increased effectively. Experimental results prove the feasibility of the proposed method.

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