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1.
Opt Express ; 29(21): 33642-33664, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809173

RESUMO

Aiming to determine the scattered estimation of complex and electrically large targets coated with the uniaxial electric anisotropic medium (UEAM) from a distributed excitation source, the demanding study is simplified by constructing the physical optics (PO) architecture which consists of three aspects, the discrete facet modeling, the tangent plane approximation, and the scattering of an infinite PEC plate coated with the UEAM based on point-source excitation, including the electric and magnetic dipole. We depict the outer surface of an electrically large scatterer as the constitution of countless tiny triangular facets. From the tangent plane approximation employed in the PO method, the scattered fields of any discretized facet induced by the equivalent electromagnetic currents (EECs) can be further evaluated as the surface fields of an infinite UEAM-coated PEC slab. Therefore, the rigorous solution of the dyadic Green's function (DGFs) for an infinite anisotropic-medium-coated PEC plate under point-source incidence is computed first. Moreover, characterizing the ray propagation process of the plane wave spectrum, the asymptotic technique of the saddle point is employed to obtain the scattered ray field in the spatial domain. Finally, the total scattered fields are obtained by the field superposition of the overall illuminated facets under point-source excitation. Compared with the reference solution, the proposed method is validated, and the simulation results of the representative shapes coated with the UEAM layer from a point source are presented.

3.
Chin Med J (Engl) ; 134(22): 2678-2684, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34802024

RESUMO

BACKGROUND: The past decade has witnessed an ever-increasing momentum of transcatheter aortic valve replacement (TAVR) and a subsequent paradigm shift in the contemporary management of severe aortic stenosis (AS). We conducted a multi-centric TAVR registry based on Chinese patients (the China Aortic valve tRanscatheter Replacement registrY [CARRY]) to delineate the clinical characteristics and outcomes of Chinese patients who underwent TAVR and compare the results between different valve types in different Chinese regions. METHODS: CARRY is an all-comer registry of aortic valve disease patients undergoing TAVR across China and was designed as an observational study that retrospectively included all TAVR patients at each participating site. Seven hospitals in China participated in the CARRY, and 1204 patients from April 2012 to November 2020 were included. Categorical variables were compared using the chi-squared test, and continuous variables were analyzed using a t test or analysis of variance (ANOVA) test. The Kaplan-Meier curve was used to estimate the risk of adverse events during follow-up. RESULTS: The mean age of the patients was 73.8 ±â€Š6.5 years and 57.2% were male. The median Society of Thoracic Surgeon-Predicted Risk of Mortality score was 6.0 (3.7-8.9). Regarding the aortic valve, the proportion of bicuspid aortic valve (BAV) was 48.5%. During the hospital stay, the stroke rate was 0.7%, and the incidence of high-degree atrioventricular block indicating permanent pacemaker implantation was 11.0%. The in-hospital all-cause mortality rate was 2.2%. After 1 year, the overall mortality rate was 4.5%. Compared to patients with tricuspid aortic valve (TAV), those with BAV had similar in-hospital complication rates, but a lower incidence of in-hospital mortality (1.4% vs. 3.3%) and 1 year mortality (2.3% vs. 5.8%). CONCLUSIONS: TAVR candidates in China were younger, higher proportion of BAV, and had lower rates of post-procedural complications and mortality than other international all-comer registries. Given the use of early generation valves in the majority of the population, patients with BAV had similar rates of complications, but lower mortality than those with TAV. These findings further propel the extension of TAVR in low-risk patients. TRIAL REGISTRATION: https://www.chictr.org.cn/ (No. ChiCTR2000038526).

5.
J Geriatr Cardiol ; 18(10): 825-835, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34754294

RESUMO

BACKGROUND: The high-degree atrioventricular block (HAVB) in patients with bicuspid aortic valve (BAV) treated with transcatheter aortic valve implantation (TAVI) remains high. The study aims to explore this poorly understood subject of mechanisms and predictors for HAVB in BAV self-expandable TAVI patients. METHODS: We retrospectively included 181 BAV patients for analysis. Using computed tomography data, the curvature of ascending aorta (AAo) was quantified by the angle (AAo angle) between annulus and the cross-section at 35 mm above annulus (where the stent interacts with AAo the most). The valvular anatomy and leaflet calcification were also characterized. RESULTS: The 30-day HAVB rate was 16.0% (median time to HAVB was three days). Type-1 morphology was found in 79 patients (43.6%) (left- and right-coronary cusps fusion comprised 79.7%). Besides implantation below membrane septum, large AAo angle [odds ratio (OR) = 1.08, P = 0.016] and type-1 morphology (OR = 4.97, P = 0.001) were found as the independent predictors for HAVB. Together with baseline right bundle branch block, these predictors showed strong predictability for HAVB with area under the cure of 0.84 (sensitivity = 62.1%, specificity = 92.8%). Bent AAo and calcified raphe had a synergistic effect in facilitating high implantation, though the former is associated with at-risk deployment (device implanted above annulus + prothesis pop-out, versus straight AAo: 9.9% vs. 2.2%, P = 0.031). CONCLUSIONS: AAo curvature and type-1 morphology are novel predictors for HAVB in BAV patients following self-expandable TAVI. For patients with bent AAo or calcified raphe, a progressive approach to implant the device above the lower edge of membrane septum is favored, though should be done cautiously to avoid pop-out.

6.
Appl Opt ; 60(25): 7530-7535, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613218

RESUMO

We experimentally demonstrate an electrically tunable superconducting device capable of switching the extraordinary terahertz (THz) transmission. The planar device consists of subwavelength hole arrays with real-time control capability. The maximum transmission coefficient at 0.33 THz is 0.98 and decreases to 0.17 when the applied voltage only increases to 1.3 V. A relative intensity modulation of 82.7% is observed, making this device an efficient THz switch. Additionally, this device exhibits good narrow-bandpass characteristics within 2 THz, which can be used as a frequency-selective component. This study offers an ideal tuning method and delivers a promising approach for designing active and miniaturized devices in THz cryogenic systems.

7.
Bioengineered ; 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34699311

RESUMO

Childhood Asthma is the most universal chronic disease, with significant cases reported. Despite the current progress in treatment, prognosis remain poor and the existing drugs cause serious side effects. This investigation explored the mechanisms and use of miR-335-5p on childhood asthma therapy. MiR-335-5p and ATG5 expression was analyzed in clinical plasma samples through RT-qPCR. Airway smooth muscle cells (ASMCs) were cultured, and transfected with miR-335-5p mimic, miR-335-5p inhibitor, and pcDNA3.1-ATG5, or co-transfected with miR-335-5p mimic + pcDNA3.1-ATG5. Asthma cell models were constructed through TGF-ß1, and animal models through ovalbumin (OVA). Monocyte-macrophage infiltration in bronchoalveolar lavage fluid (BALF) was determined by May-Grunwald-Giemsa staining, and collagen in lung tissue was assessed via Masson staining. Relationship between miR-335-5p and ATG5 was detected by Dual luciferase assay. Cell proliferation was detected by MTT assay. MiR-335-5p and ATG5 RNA expression was determined by RT-qPCR. Collagen I, collagen III, α-SMA, ATG5, LC3I/II, Beclin-1, and p62 protein expression levels in ASMCs was detected by western blot. MiR-335-5p expression was low, but ATG5 expression was high in childhood asthma. Versus OVA+ mimic NC group, the number of eosinophil and collagen in OVA+ miR-335-5p mimic group were reduced. In contrast to TGF-ß1 + mimic NC group, TGF-ß1 + miR-335-5p mimic group reduced inflammatory, airway fibrosis and autophagy in ASMCs. ATG5 was miR-335-5p target. Overexpressing ATG5 significantly reversed the inhibitory effects of miR-335-5p on inflammatory response, fibrosis and autophagy in ASMCs. Overall, the study concludes that MiR-335-5p alleviate inflammatory response, airway fibrosis and autophagy in childhood asthma through targeted regulation of ATG5.

8.
Foodborne Pathog Dis ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520252

RESUMO

To disclose the antimicrobial susceptibility and wide adaptability of commonly occurring genotypes of Salmonella enterica serovar Typhimurium, the antimicrobial resistance and multilocus sequence typing (MLST) profiles of 196 Salmonella Typhimurium isolates (136 from food-producing animals, 19 from environments, 15 from markets, and 26 from humans) in China between 2007 and 2019 were analyzed. Tests of susceptibility to 19 antimicrobial agents using the broth microdilution method showed that 84.7% of the isolates were resistant to at least one antimicrobial. Antimicrobial susceptibility analysis demonstrated that 66.8% of the isolates were multidrug-resistant (MDR) strains, with resistance to three or more antimicrobials. The highest antidrug resistance was to ampicillin, amoxicillin/clavulanic acid, and tetracycline. Three MLST types were detected, and sequence type (ST) 19 was the most common ST. However, ST34 was associated with a higher MDR rate and more complex MDR patterns, than ST19 and ST99, although the exact mechanism has not been reported. Our study highlights the variation of drug resistance and STs from different sources and the association between STs and drug resistance, providing useful information for epidemiological research and developing a public health strategy.

9.
Mil Med Res ; 8(1): 51, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517915

RESUMO

To determine the prevalence and clinical features of olfactory and taste disorders among coronavirus disease 2019 (COVID-19) patients in China. A cross-sectional study was performed in Wuhan from April 3, 2020 to April 15, 2020. A total of 187 patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) completed face-to-face interviews or telephone follow-ups. We found that the prevalence of olfactory and taste disorders was significantly lower in the Chinese cohort than in foreign COVID-19 cohorts. Females were more prone to olfactory and taste disorders. In some patients, olfactory and taste disorders precede other symptoms and can be used as early screening and warning signs.


Assuntos
COVID-19/complicações , Transtornos do Olfato/etiologia , Olfato , Distúrbios do Paladar/etiologia , Paladar , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/epidemiologia , Prevalência , SARS-CoV-2 , Fatores Sexuais , Distúrbios do Paladar/epidemiologia , Adulto Jovem
10.
Front Immunol ; 12: 692733, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34367151

RESUMO

Background: The calcium-binding protein S100A4 demonstrates important regulatory roles in many biological processes including tumorigenesis and inflammatory disorders such as allergy. However, the specific mechanism of the contribution of S100A4 to allergic diseases awaits further clarification. Objective: To address the effect of S100A4 on the regulation of mast cell activation and its impact on allergy. Methods: Bone marrow-derived cultured mast cells (BMMCs) were derived from wild-type (WT) or S100A4-/- mice for in vitro investigation. WT and S100A4-/- mice were induced to develop a passive cutaneous anaphylaxis (PCA) model, a passive systemic anaphylaxis (PSA) model, and an ovalbumin (OVA)-mediated mouse asthma model. Results: Following OVA/alum-based sensitization and provocation, S100A4-/- mice demonstrated overall suppressed levels of serum anti-OVA IgE and IgG antibodies and proinflammatory cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung exudates. S100A4-/- mice exhibited less severe asthma signs which included inflammatory cell infiltration in the lung tissue and BALF, and suppressed mast cell recruitment in the lungs. Reduced levels of antigen reencounter-induced splenocyte proliferation in vitro were recorded in splenocytes from OVA-sensitized and challenged mice that lacked S100A4-/-. Furthermore, deficiency in the S100A4 gene could dampen mast cell activation both in vitro and in vivo, evidenced by reduced ß-hexosaminidase release and compromised PCA and PSA reaction. We also provided evidence supporting the expression of S100A4 by mast cells. Conclusion: S100A4 is required for mast cell functional activation, and S100A4 may participate in the regulation of allergic responses at least partly through regulating the activation of mast cells.

11.
J Cancer Res Ther ; 17(3): 777-783, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34269313

RESUMO

Context: Postembolization syndrome (PES) is the most common complication in patients with hepatocellular carcinoma (HCC) who had undergone transcatheter arterial chemoembolization (TACE). PES was defined as fever, nausea and/or vomiting, and abdominal pain and these symptoms develop within 1-3 days after TACE. However, few studies have explored the factors influencing PES in patients with TACE for the first time. Aims: We explored the factors influencing PES in patients with HCC undergoing TACE for the first time. Settings and Design: The present study was a hospital-based study conducted in the tertiary care hospital of Guangzhou with a retrospective study design. Subjects and Methods: In this single-center retrospective study, a total of 242 patients with HCC were included in the first TACE program between November 1, 2018 and November 31, 2019. Statistical Analysis Used: T-test and Chi-square test revealed the factors affecting the occurrence of PES. Correlation analysis (Spearman) explored the relationship between these factors and PES. Binary logistics analyzed the predictive factors of PES. Results: The probability of PES in patients with HCC undergoing TACE for the first time was 55.45%. Types of embolic agents (r = 0.296), types of microspheres (r = 0.510), number of microspheres (r = 0.130), maximum diameter of microspheres used (r = 0.429), type of drug (r = 0.406), and drug loading (r = 0.433) were positively correlated with PES (P < 0.05). Serum albumin was negatively correlated with PES (P = 0.008, r = -0.170). Binary logistic regression analysis revealed that drug loading microspheres (odds ratio [OR] = 0.075, 95% confidence interval [CI] = 0.031-0.180) and serum albumin (OR = 0.182, 95% CI = 0.068-0.487) were the protective factors influencing PES, while drug loading was the risk factor of PES (OR = 1.407, 95% CI = 1.144-1.173). Conclusions: Drug loading microspheres, serum albumin, and drug loading were the predictors of PES after the first TACE.

12.
Org Lett ; 23(15): 5853-5858, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34296878

RESUMO

Four unprecedented base-catalyzed/mediated nucleophilic additions of TMSCN to α-(trifluoromethyl)styrenes and 2-trifluoromethyl enynes were developed. The reaction proceeded smoothly at room temperature under mild and transition-metal-free conditions without affecting the trifluoromethyl group and afforded the corresponding CF3-containing alkyl, alkynyl, and butadienyl nitriles in moderate to excellent yields in a highly regioselective manner, respectively.

13.
Polymers (Basel) ; 13(14)2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34301110

RESUMO

This study develops a unified phenomenological creep model for polymer-bonded composite materials, allowing for predicting the creep behavior in the three creep stages, namely the primary, the secondary, and the tertiary stages under sustained compressive stresses. Creep testing is performed using material specimens under several conditions with a temperature range of 20 °C-50 °C and a compressive stress range of 15 MPa-25 MPa. The testing data reveal that the strain rate-time response exhibits the transient, steady, and unstable stages under each of the testing conditions. A rational function-based creep rate equation is proposed to describe the full creep behavior under each of the testing conditions. By further correlating the resulting model parameters with temperature and stress and developing a Larson-Miller parameter-based rupture time prediction model, a unified phenomenological model is established. An independent validation dataset and third-party testing data are used to verify the effectiveness and accuracy of the proposed model. The performance of the proposed model is compared with that of an existing reference model. The verification and comparison results show that the model can describe all the three stages of the creep process, and the proposed model outperforms the reference model by yielding 28.5% smaller root mean squared errors on average.

14.
Biochem Biophys Res Commun ; 567: 222-229, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34217974

RESUMO

Cyclin D1 (CCND1) has been identified as a metastatic promoter in various tumors including lung adenocarcinoma (LUAD), a subtype of non small cell lung cancer (NSCLC). The previous observation revealed that CCND1 was upregulated in NSCLC and predicted poor prognosis of LUAD patients. In this study, we examined a chaperonin containing TCP1 subunit 5 (CCT5) protein interacts with CCND1 in LUAD. Immunofluorescence demonstrated the co-localization of CCT5 and CCND1 protein in LUAD cells. CCT5 expression was detected with both immunohistochemistry (IHC) and bioinformatics analyses. Similar with the expression pattern of CCND1, CCT5 displayed a high level in LUAD tissues compared to non cancerous lung specimens. Patients with high CCT5 expression showed a significant shorter overall survival relative to those with low expression level. Furthermore, upregulated CCT5 exhibited significant positive correlation with TNM stage of LUAD patients in both IHC analyses and bioinformatics. Knocking down CCT5 remarkably inhibited LUAD cell migration and invasion in vitro by inactivating PI3K/AKT and its downstream EMT signals, which could abrogated the accelerated migration and invasion caused by CCND1 overexpression. In summary, our study discovered a highly expressed protein CCT5 in LUAD which interacted with CCND1 and promoted migration and invasion of LUAD cells by positively moderating PI3K/AKT-induced EMT pathway.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Chaperonina com TCP-1/metabolismo , Ciclina D1/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Movimento Celular , Humanos , Neoplasias Pulmonares/patologia , Invasividade Neoplásica/patologia , Mapas de Interação de Proteínas
16.
Polymers (Basel) ; 13(9)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923092

RESUMO

This study develops a general temperature-dependent stress-strain constitutive model for polymer-bonded composite materials, allowing for the prediction of deformation behaviors under tension and compression in the testing temperature range. Laboratory testing of the material specimens in uniaxial tension and compression at multiple temperatures ranging from -40 ∘C to 75 ∘C is performed. The testing data reveal that the stress-strain response can be divided into two general regimes, namely, a short elastic part followed by the plastic part; therefore, the Ramberg-Osgood relationship is proposed to build the stress-strain constitutive model at a single temperature. By correlating the model parameters with the corresponding temperature using a response surface, a general temperature-dependent stress-strain constitutive model is established. The effectiveness and accuracy of the proposed model are validated using several independent sets of testing data and third-party data. The performance of the proposed model is compared with an existing reference model. The validation and comparison results show that the proposed model has a lower number of parameters and yields smaller relative errors. The proposed constitutive model is further implemented as a user material routine in a finite element package. A simple structural example using the developed user material is presented and its accuracy is verified.

17.
Pharmaceutics ; 13(4)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921712

RESUMO

Oral propranolol hydrochloride has been the first-line treatment for infantile hemangioma (IH), whereas systemic exposure to propranolol has the potential of causing serious adverse reactions. Dermal delivery of propranolol is preferable due to high local drug concentration and fewer adverse effects. However, propranolol hydrochloride (BCS class I) is highly hydrophilic and has difficulty in penetrating the stratum corneum (SC) barrier. Dissolving microneedles (MNs) are an efficient tool for overcoming the barrier of the SC and enhancing dermal drug delivery. In this study, propranolol hydrochloride-loaded dissolving MNs were fabricated by using hyaluronic acid and polyvinyl pyrrolidone as matrix materials. Controllable drug loading in needle tips was achieved by a two-step casting procedure. The needles were good in mechanical strength for penetrating the SC while presented excellent dissolving capability for releasing propranolol hydrochloride. In comparison with the solution counterpart, irrespective of being applied to intact skin or solid MNs-pretreated skin, dissolving MNs significantly increased the permeability and skin retention of propranolol. In conclusion, dissolving MNs could be a potential approach for enhancing dermal delivery of propranolol to treat IH.

18.
Stem Cell Res ; 53: 102339, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33892291

RESUMO

In this study, skin biopsy was collected from a healthy 48-year old male donor with informed consent, and the fibroblasts were isolated from the dermal explant cultures. Here, a human induced pluripotent stem cell (iPSC) line was derived from the fibroblasts using the reprogramming four Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc). The generated iPSCs were integration-free, displayed the normal karyotype, expressed pluripotency markers and demonstrated trilineage differentiation potential in vitro. This iPSC model will be useful for investigating physiological processes, drug validation as well as a control in pathological mechanistic studies.


Assuntos
Células-Tronco Pluripotentes Induzidas , Diferenciação Celular , Reprogramação Celular , Fibroblastos , Humanos , Masculino , Pessoa de Meia-Idade , Pele
19.
Bioact Mater ; 6(9): 2829-2840, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33718665

RESUMO

In recent years, the developed hemostatic technologies are still difficult to be applied to the hemostasis of massive arterial and visceral hemorrhage, owing to their weak hemostatic function, inferior wet tissue adhesion, and low mechanical properties. Herein, a mussel-inspired supramolecular interaction-cross-linked hydrogel with robust mechanical property (308.47 ± 29.20 kPa) and excellent hemostatic efficiency (96.5% ± 2.1%) was constructed as a hemostatic sealant. Typically, we combined chitosan (CS) with silk fibroin (SF) by cross-linking them through tannic acid (TA) to maintain the structural stability of the hydrogel, especially for wet tissue adhesion ability (shear adhesive strength = 29.66 ± 0.36 kPa). Compared with other materials reported previously, the obtained CS/TA/SF hydrogel yielded a lower amount of blood loss and shorter time to hemostasis in various arterial and visceral bleeding models, which could be ascribed to the synergistic effect of wound closure under wet state as well as intrinsic hemostatic activity of CS. As a superior hemostatic sealant, the unique hydrogel proposed in this work can be exploited to offer significant advantages in the acute wound and massive hemorrhage with the restrictive access of therapeutic moieties.

20.
Cell ; 184(7): 1895-1913.e19, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33657410

RESUMO

A dysfunctional immune response in coronavirus disease 2019 (COVID-19) patients is a recurrent theme impacting symptoms and mortality, yet a detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 196 COVID-19 patients and controls and created a comprehensive immune landscape with 1.46 million cells. The large dataset enabled us to identify that different peripheral immune subtype changes are associated with distinct clinical features, including age, sex, severity, and disease stages of COVID-19. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was found in diverse epithelial and immune cell types, accompanied by dramatic transcriptomic changes within virus-positive cells. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis of and developing effective therapeutic strategies for COVID-19.


Assuntos
COVID-19/imunologia , Megacariócitos/imunologia , Monócitos/imunologia , RNA Viral , SARS-CoV-2/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , China , Estudos de Coortes , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , RNA Viral/isolamento & purificação , Análise de Célula Única , Transcriptoma/imunologia , Adulto Jovem
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