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1.
Int J Mol Med ; 46(5): 1653-1660, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000177

RESUMO

Circular RNAs (circRNAs) are reported to be aberrantly expressed and perform different functions in numerous types of tumor; however, their expression levels in cutaneous squamous cell carcinoma (CSCC) remain largely unclear. Thus, the purpose of the present study was to investigate the function of circRNA_001937 in CSCC. Differential circRNA expression profiles of CSCC were analyzed using the Arraystar Human circRNAs chip and reverse transcription­quantitative PCR (RT­qPCR); and the effects of circRNA_001937 on cell behavior, in particular its regulation over the microRNA (miRNA)­597­3p/Fos­related antigen 2 (FOSL2) pathway, was investigated using a dual­luciferase reporter assay, and verified using RT­qPCR and western blotting. circRNA_001937 expression levels were significantly increased in CSCC tissues and cell lines compared with the corresponding adjacent tissues and control cells (P<0.05). The genetic silencing of circRNA_001937 with small interfering RNA significantly inhibited cell proliferation, and induced cell apoptosis (P<0.05). circRNA_001937 was observed to directly bind to miRNA­597­3p and serve as a sponge, which indirectly increased the expression levels of FOSL2, a miRNA­597­3p target gene. In conclusion, circRNA_001937 expression was increased in CSCC and silencing circRNA_001937 gene expression may inhibit CSCC progression by sponging the miRNA­597­3p/FOSL2 pathway.

2.
Mol Med Rep ; 22(5): 4236-4242, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000271

RESUMO

DEAD­Box Helicase 46 (DDX46) is an ATP­dependent RNA helicase that plays a central role in transcription splicing and ribosome assembly. However, the role of DDX46 in cutaneous squamous cell carcinoma (CSCC) remains to be elucidated. The aim of the present study was to investigate the role of DDX46 in CSCC by assessing DDX46 expression levels in CSCC tissues and cell lines. The effect of DDX46 silencing on CSCC cell proliferation, apoptosis and autophagy were also analyzed. It was demonstrated that DDX46 was significantly overexpressed in CSCC tissues and cells (P<0.05). Furthermore, it was found that DDX46 silencing could dramatically inhibit cell proliferation (P<0.05). Moreover, cell apoptosis and autophagy were activated in DDX46 silencing groups (P<0.05). Therefore, the present results suggested that DDX46 was overexpressed in CSCC and that DDX46 silencing can inhibit cell proliferation by inducing apoptosis and activating autophagy. Thus, DDX46 may serve as a novel potential therapeutic target for CSCC.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33029917

RESUMO

Internal uranium contamination as a consequence of uranium mining, nuclear incident, and nuclear terrorist attacks is one of the most significant concerns in society today. The most effective strategies for dealing with this issue, if it arises, is to develop new materials that can rapidly capture and remove the uranium from the body. However, current selections of state-of-the-art antidotal agents suffer from clear drawbacks dealing with limited uranium capture capability, poor selectivity, and/or high toxicity. Here, we propose a new agent for actinide antidotal therapy with fast uranium uptake kinetics and efficient in vivo uranium removal by a nanoscale metal-organic framework (nano-MOF). UiO-66 nanoparticles post-synthetically functionalized with carboxyl groups, UiO-66-(COOH) 4 -180, exhibit the fastest uranium uptake kinetics reported with more than 65% of uranyl in fetal bovine serum (FBS) removed within 5 min. Moreover, the in vivo bio-distribution studies show that the material accumulates in kidneys and femurs where uranium mainly deposits facilitating the in vivo removal of uranium. The results of the in vivo uranium removal assays with mice show that UiO-66-(COOH) 4 -180 could successfully reduce the amounts of uranyl deposited in kidneys and femurs by up to 55.4% and 36.5%, respectively, and is significantly more efficient than the commercial actinide decorporation agent, ZnNa 3 -DTPA.

4.
Ecotoxicol Environ Saf ; 208: 111412, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33039872

RESUMO

Cadmium (Cd) is a severely toxic and carcinogenic heavy metal. Cigarette smoking is one of the major source of Cd exposure in humans. Nicotiana tabacum is primarily a leaf Cd accumulator, while Nicotiana rustica is a root Cd accumulator among Nicotiana species. However, little is known about the mechanisms of differential Cd translocation and accumulation in Nicotiana. To find the key factors, Cd concentration, Cd chemical forms, and transcriptome analysis were comparatively studied between N. tabacum and N. rustica under control or 10 µM Cd stress. The leaf/root Cd concentration ratio of N. tabacum was 2.26 and that of N. rustica was 0.14. The Cd concentration in xylem sap of N. tabacum was significantly higher than that of N. rustica. The root of N. tabacum had obviously higher proportion of ethanol extractable Cd (40%) and water extractable Cd (16%) than those of N. rustica (16% and 6%). Meanwhile the proportion of sodium chloride extracted Cd in N. rustica (71%) was significantly higher than that in N. tabacum (30%). A total of 30710 genes expressed differentially between the two species at control, while this value was 30,294 under Cd stress, among which 27,018 were collective genes, manifesting the two species existed enormous genetic differences. KEGG pathway analysis showed the phenylpropanoid biosynthesis pathway was overrepresented between the two species under Cd stress. Several genes associated with pectin methylesterase, suberin and lignin synthesis, and heavy metal transport were discovered to be differential expressed genes between two species. The results suggested that the higher accumulation of Cd in the leaf of N. tabacum depends on a comprehensive coordination of Cd transport, including less cell wall binding, weaker impediment by the Casparian strip, and efficient xylem loading.

5.
Ann Plast Surg ; 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32881745

RESUMO

BACKGROUND: A plump single eyelid with ptosis is the morphological feature of Asians. Orbicularis oculi muscle (OOM) technique can correct ptosis and get a good appearance. METHODS: A retrospective study was conducted in 121 Chinese patients who underwent double eyelid surgery with medial epicanthoplasty using OOM resection technique from December 2016 to December 2019. Preoperatively, all the patients had good or excellent levator function while skin fold overlapping the upper eyelid margin was found. Palpebral fissure height, upper eyelid margin reflex distance, complications, and cosmetic results were evaluated. Comparisons were performed preoperatively and postoperatively. RESULTS: The study included 121 patients. Mean follow-up time was 12.8 months (range, 6-32 months). Mean margin reflex distance increased from 1.96 ± 0.60 mm preoperatively to 3.74 ± 0.50 mm postoperatively (P < 0.001), mean palpebral fissure height increased from 6.31 ± 0.51 mm preoperatively to 8.33 ± 0.52 mm postoperatively (P < 0.001). Most patients obtained satisfactory results. Only 1 patient was under correction, 2 patients were with mild asymmetry 6 months postoperatively. CONCLUSIONS: Ptosis of the upper eyelid can be corrected by the OOM resection technique without any procedure on levator muscle. This technique can be an alternative method for the correction of ptosis of the upper eyelid.

6.
Biomed Pharmacother ; 131: 110652, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32942151

RESUMO

The application of tissue engineering to generate cartilage is limited because of low proliferative ability and unstable phenotype of chondrocytes. The sources of cartilage seed cells are mainly chondrocytes and stem cells. A variety of methods have been used to obtain large numbers of chondrocytes, including increasing chondrocyte proliferation and stem cell chondrogenic differentiation via cytokines, genes, and proteins. Natural or synthetic small molecule compounds can provide a simple and effective method to promote chondrocyte proliferation, maintain a stable chondrocyte phenotype, and promote stem cell chondrogenic differentiation. Therefore, the study of small molecule compounds is of great importance for cartilage tissue engineering. Herein, we review a series of small molecule compounds and their mechanisms that can promote chondrocyte proliferation, maintain chondrocyte phenotype, or induce stem cell chondrogenesis. The studies in this field represent significant contributions to the research in cartilage tissue engineering and regenerative medicine.

7.
PLoS Negl Trop Dis ; 14(9): e0008584, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941447

RESUMO

Coronavirus disease 2019 (COVID-19) has recently emerged as a global threat. Understanding workers' knowledge, attitudes, and practices (KAP) regarding this new infectious disease is crucial to preventing and controlling it. This study aimed to assess KAP regarding COVID-19 during the outbreak among workers in China. The present study was part of a cross-sectional online survey study conducted based on a large labor-intensive factory, which has 180,000 workers from various Chinese provinces, from 2 February 2020 to 7 February 2020. KAP related to COVID-19 were measured by 32 items, each item was measured with an agree/disagree/unclear format, and only correct responses were given 1 point. KAP regarding COVID-19 were measured with 20 items, 6 items and 6 items, respectively. A total of 123,768 valid responses (68.8%) were included in the analysis. Generally, the levels of knowledge (mean: 16.3 out of 20 points), attitudes (mean: 4.5 out of 6 points), and practices (mean: 5.8 out of 6 points) related to COVID-19 were high. Only 36,373 respondents (29.4%) disagreed that gargling with salt water is effective in protecting against COVID-19. Moreover, older respondents had decreased levels of knowledge and practices related to COVID-19 (both P values for the trend <0.001), while better-educated respondents had increased levels of knowledge and practices related to COVID-19 (both P values for the trend <0.001). These results suggest that Chinese workers are highly aware of COVID-19, but health authorities still need to provide correct information on COVID-19 prevention and strengthen health interventions, particularly for older and less-educated workers.


Assuntos
Infecções por Coronavirus/patologia , Infecções por Coronavirus/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Pandemias/prevenção & controle , Pneumonia Viral/patologia , Pneumonia Viral/prevenção & controle , Adulto , Betacoronavirus , China , Estudos Transversais , Feminino , Humanos , Masculino , Instalações Industriais e de Manufatura , Pessoa de Meia-Idade , Inquéritos e Questionários
8.
Proteomics ; 20(19-20): e2000167, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32865869

RESUMO

Sperm proteins play vital roles in fertilization, but little is known about their identities in free-spawning marine invertebrates. Here, 286 sperm proteins are reported from the Hong Kong oyster Crassostrea hongkongensis using label-free and semi-quantitative proteomics. Proteins extracted from three sperm samples are separated by SDS-PAGE, analyzed by LC-MS/MS, and identified using Mascot. Functional classification of the sperm proteome reveals energy metabolism (33%), signaling and binding (23%), and protein synthesis and degradation (12%) as the top functional categories. Comparison of orthologous sperm proteins between C. hongkongensis, Crassostrea gigas, Mytilus edulis, and M. galloprovincialis suggests that energy metabolism (48%) is the most conserved functional group. Sequence alignment of the C. hongkongensis bindin, an acrosomal protein that binds the sperm and the egg, with those of three other Crassostrea species, reveals several conserved motifs. The study has enriched the data of invertebrate sperm proteins and may contribute to studies of mechanisms of fertilization in free-spawning invertebrates. The proteomic data are available in ProteomeXchange with the identifier PXD018255.

10.
Mucosal Immunol ; 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32690871

RESUMO

A disintegrin and metalloproteinase domain-15 (ADAM15) is expressed by cells implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD), but its contributions to COPD are unknown. To address this gap, ADAM15 levels were measured in samples from cigarette smoke (CS)-versus air-exposed wild-type (WT) mice. CS-induced COPD-like disease was compared in CS-exposed WT, Adam15-/-, and Adam15 bone marrow chimeric mice. CS exposure increased Adam15 expression in lung macrophages and CD8+ T cells and to a lesser extent in airway epithelial cells in WT mice. CS-exposed Adam15-/- mice had greater emphysema, small airway fibrosis, and lung inflammation (macrophages and CD8+ T cells) than WT mice. Adam15 bone marrow chimera studies revealed that Adam15 deficiency in leukocytes led to exaggerated pulmonary inflammation and COPD-like disease in mice. Adam15 deficiency in CD8+ T cells was required for the exaggerated pulmonary inflammation and COPD-like disease in CS-exposed Adam15-/- mice (as assessed by genetically deleting CD8+ T cells in Adam15-/- mice). Adam15 deficiency increased pulmonary inflammation by rendering CD8+ T cells and macrophages resistant to CS-induced activation of the mitochondrial apoptosis pathway by preserving mTOR signaling and intracellular Mcl-1 levels in these cells. These results strongly link ADAM15 deficiency to the pathogenesis of COPD.

11.
Respir Res ; 21(1): 188, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32677970

RESUMO

BACKGROUND: A disintegrin and metalloproteinase domain-15 (ADAM15) is expressed by activated leukocytes, and fibroblasts in vitro. Whether ADAM15 expression is increased in the lungs of COPD patients is not known. METHODS: ADAM15 gene expression and/or protein levels were measured in whole lung and bronchoalveolar lavage (BAL) macrophage samples obtained from COPD patients, smokers, and non-smokers. Soluble ADAM15 protein levels were measured in BAL fluid (BALF) and plasma samples from COPD patients and controls. Cells expressing ADAM15 in the lungs were identified using immunostaining. Staining for ADAM15 in different cells in the lungs was related to forced expiratory volume in 1 s (FEV1), ratio of FEV1 to forced vital capacity (FEV1/FVC), and pack-years of smoking history. RESULTS: ADAM15 gene expression and/or protein levels were increased in alveolar macrophages and whole lung samples from COPD patients versus smokers and non-smokers. Soluble ADAM15 protein levels were similar in BALF and plasma samples from COPD patients and controls. ADAM15 immunostaining was increased in macrophages, CD8+ T cells, epithelial cells, and airway α-smooth muscle (α-SMA)-positive cells in the lungs of COPD patients. ADAM15 immunostaining in macrophages, CD8+ T cells and bronchial (but not alveolar) epithelial cells was related inversely to FEV1 and FEV1/FVC, but not to pack-years of smoking history. ADAM15 staining levels in airway α-SMA-positive cells was directly related to FEV1/FVC. Over-expressing ADAM15 in THP-1 cells reduced their release of matrix metalloproteinases and CCL2. CONCLUSIONS: These results link increased ADAM15 expression especially in lung leukocytes and bronchial epithelial cells to the pathogenesis of COPD.

12.
Neurochem Res ; 45(10): 2324-2335, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32681443

RESUMO

Isoflurane, an anesthetic, can aggravate the progression of Alzheimer's disease (AD). Long non-coding RNA ß-secretase 1 (BACE1)-antisense transcript (BACE1-AS) and miR-214-3p are related to AD progression. Nevertheless, it is unclear whether BACE1-AS is involved in the development of isoflurane-mediated AD via miR-214-3p. Amyloid beta peptide (Aß) was employed to construct the AD cell model. The expression of BACE1-AS and miR-214-3p in the plasma of AD patients and SK-N-SH and SK-N-AS cells treated with Aß and isoflurane was assessed through quantitative reverse transcription polymerase chain reaction (qRT-PCR). The proliferation and apoptosis of Aß-treated SK-N-SH and SK-N-AS cells were determined via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) or flow cytometry assays, respectively. Protein levels of B cell lymphoma 2 (Bcl-2), Bcl-2-associated X (Bax), CyclinD1, microtubule-associated protein A1/1B-light chain3 (LC3 I/LC3 II), p62 and Beclin1 were detected via western blot analysis. The relationship between BACE1-AS and miR-214-3p was verified by dual-luciferase reporter assay. We found that BACE1-AS was upregulated and miR-214-3p was downregulated in the plasma of AD patients and SK-N-SH and SK-N-AS cells treated with Aß and isoflurane. Both BACE1-AS depletion and miR-214-3p augmentation restored the suppression of proliferation and the facilitation of apoptosis and autophagy of Aß-treated SK-N-SH and SK-N-AS cells induced by isoflurane. Importantly, BACE1-AS acted as a sponge for miR-214-3p. Additionally, miR-214-3p silencing reversed the influence of BACE1-AS knockdown on isoflurane-mediated proliferation, apoptosis and autophagy in Aß-induced SK-N-SH and SK-N-AS cells. In conclusion, BACE1-AS aggravated isoflurane-induced neurotoxicity to AD via sponging miR-214-3p.

13.
BMC Nephrol ; 21(1): 210, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493274

RESUMO

BACKGROUND: Blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) and diffusion tensor imaging (DTI) are useful methods for investigating the morphology and function of the kidneys, including revealing unilateral renal damage. Nevertheless, these techniques have not yet been applied for bilateral renal function. The aim of this study was to investigate whether the combination of DTI and BOLD could be used to examine different degrees of contrast-induced acute kidney injury (CI-AKI) in bilateral kidneys compared to standard methods such as serum creatinine (SCr) detection. METHODS: Forty-Two New Zealand white rabbits were divided into two groups: the experimental group and the control group. Physiological saline and iodine contrast agent (iohexol, 1.0 g iodine/kg, 1.0 ml/sec) were injected via the right renal artery. DTI and BOLD-MR data were acquired longitudinally at the baseline and 1, 24, 48, and 72 h after high-pressure syringe injection to measure the apparent diffusion coefficient (ADC), fractional anisotropy (FA) and relative transverse relaxation rate (R2*). After the MR scan at each time point, three rabbits in each group were sacrificed, and changes in SCr and hypoxia-inducible factor-1α (HIF-1α) were analyzed using histopathology and immunochemistry. RESULTS: Twenty-four hours after iohexol administration, the values of ADC and FA decreased significantly (P < 0.05), while R2* values increased (P < 0.05) in the renal cortex (CO), outer medulla (OM) and inner medulla (IM). Besides, significant negative correlations were observed among ADC, FA, and R2* in CO, OM, and IM (all P < 0.001, r = - 0.654-0.828). CONCLUSIONS: DTI and BOLD can simultaneously and non-invasively assess different degrees of CI-AKI in bilateral kidneys.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32567828

RESUMO

Exploring inexpensive and earth-abundant transition metal-nitrogen-based carbon (MNC) catalysts to substitute the scarce and costly Pt-based electrocatalysts for the oxygen reduction reaction (ORR) is quite anticipated in metal-air batteries (MABs). Here, we demonstrate a facile vacuum-annealing method to synthesize Cu nanoclusters/FeN4 amorphous composites embedded in N-doped graphene (Cu/Fe-NG). This approach avoids the long-term pyrolysis procedure and the use of an inert atmosphere in the conventional procedure for fabricating MNC catalysts. Interestingly, we discovered that the amorphous structure of Cu/FeN4 composites can provide high-activity bimetallic M-Nx sites (M = Cu, Fe), because of which the Cu/FeN4 composites exhibit boosted electrocatalytic activity with a positive half-wave potential of 0.88 V (vs RHE), long-term durability, and low hydrogen peroxide for the ORR. The origin of this enhancement was assigned to the concomitance of Fe-N4 and Cu-Nx moieties in Cu/Fe-NG, favoring adsorption and activation of the O2 molecule as suggested by X-ray absorption fine structure (XAFS) analyses and density functional theory (DFT) calculations. Moreover, examinations of Cu/Fe-NG in both liquid and quasi-solid-state Zn-air batteries (ZABs) can exhibit remarkable performances. This work may offer facile fabrication of enhanced performance MNC catalysts as well as a profound insight into the use of amorphous materials in the ORR and ZABs.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32551509

RESUMO

Li dendrites are considered as the primary cause for degradation and inevitable short circuit in lithium-metal batteries (LMBs). Although contemporary strategies have shown potential for addressing dendrite growth, none have achieved complete elimination. In this paper, a dendrite-free, three-dimensional, ordered, macro/mesoporous Cu/Zn current collector was prepared using a combination of simple colloidal crystal template and electrochemical method (electrodeposition and pulse plating). When paired with a hierarchically structured mesoporous (20-50 nm) and macroporous (450 nm) anode, this novel current collector achieved stable charge/discharge cycles of over 2000 h and a small plating/stripping potential (≈8 mV) at a current density of 0.2 mA cm-2. Coulombic efficiencies (CE) also reached 94.7% after 400 cycles. This three-dimensional, ordered, macro/mesoporous structure provides a greater specific surface area, reduces local current density, and contains a lithiophilic Zn coating that serves as preferred Li nucleation sites. By combining these factors, dendrite-free Li deposition and superior electrochemical performance improvements in LMBs have been realized.

16.
BMC Genet ; 21(1): 63, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32552710

RESUMO

BACKGROUND: The disease gene of fragile X syndrome, FMR1 gene, encodes fragile X mental retardation protein (FMRP). The alternative splicing (AS) of FMR1 can affect the structure and function of FMRP. However, the biological functions of alternatively spliced isoforms remain elusive. In a previous study, we identified a new 140bp exon from the intron 9 of human FMR1 gene. In this study, we further examined the biological functions of this new exon and its underlying signaling pathways. RESULTS: qRT-PCR results showed that this novel exon is commonly expressed in the peripheral blood of normal individuals. Comparative genomics showed that sequences paralogous to the 140 bp sequence only exist in the genomes of primates. To explore the biological functions of the new transcript, we constructed recombinant eukaryotic expression vectors and lentiviral overexpression vectors. Results showed that the spliced transcript encoded a truncated protein which was expressed mainly in the cell nucleus. Additionally, several genes, including the BEX1 gene involved in mGluR-LTP or mGluR-LTD signaling pathways were significantly influenced when the truncated FMRP was overexpressed. CONCLUSIONS: our work identified a new exon from amid intron 9 of human FMR1 gene with wide expression in normal healthy individuals, which emphasizes the notion that the AS of FMR1 gene is complex and may in a large part account for the multiple functions of FMRP.

17.
Med Phys ; 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32583468

RESUMO

PURPOSE: Respiratory gating reduces respiratory blur in cardiac single photon emission computed tomography (SPECT). It can be implemented as three gating schemes: (a) equal amplitude-based gating (AG); (b) phase or time-based gating (TG); or (c) equal count-based gating (CG), that is, a variant of amplitude-based method. The goal of this study is to evaluate the effectiveness of these respiratory gating methods for patients with different respiratory patterns in myocardial perfusion SPECT. METHODS: We reviewed 1274 anonymized patient respiratory traces obtained via the Vicon motion-tracking system during their 99m Tc-sestamibi SPECT scans and grouped them into four breathing categories: (a) regular respiration (RR); (b) periodic respiration (PR); (c) respiration with apnea (AR); and (d) unclassified respiration (UR). For each respiratory pattern, 15 patients were randomly selected and their list-mode data were rebinned using the three gating schemes. A preliminary reconstruction was performed for each gate with the heart region segmented and registered to a reference gate to estimate the respiratory motion. A final reconstruction incorporating respiratory motion correction was done to get a final image set. The estimated respiratory motion, the full-width-at-half-maxima (FWHM) measured across the image intensity profile of the left ventricle wall, as well as the normalized standard deviation measured in a uniform cuboid region of the thorax were analyzed. RESULTS: There are 47.1%, 24.3%, 13.5%, and 15.1% RR, PR, AR, and UR patients, respectively, among the 1274 patients in this study. The differences among the three gating schemes in RR were smaller than other respiratory patterns. The AG and CG methods showed statistically larger motion estimation than TG particularly in the AR and PR patterns. Noise of AG varied more in different gates, especially for AR and UR patterns. CONCLUSION: More than half of the patients reviewed exhibited nonregular breathing patterns. Amplitude-based gating, that is, AG and CG, is a preferred gating method for such patterns and is a robust respiratory gating implementation method given the respiratory pattern of the patients is unknown before data acquisition. Phase gating is also a feasible option for regular respiratory pattern.

18.
PLoS One ; 15(5): e0233434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437408

RESUMO

This paper reports an experimental study on the electrical properties of five coal samples taken from various Chinese coal mines. The dielectric permittivity and specific resistivity of grinded coal samples subjected to electromagnetic (EM) fields in a wide frequency spectrum were determined. Based on the experimental data, a set of approximating equations of the change in electric properties the 100-1000 MHz frequency region was obtained. These equations, along with EM equations for EM speed and attenuation, were used for modeling and studying radar-wave propagation in a coal seam and radar-wave reflection from the body of miners trapped in collapsed tunnels. The modeling concept assumes that a radar transducer with the dominating frequency of 500 MHz is lowered through a vertical or inclined rescue borehole to the depth of the coal seam. It is assumed that only the miner is present in the part of the tunnel that did not collapse. Thus, in the path of the radar wave from the transducer to the human body, only one geological interface reflecting the radar signals is present (coal-air) and one is connected with human body. The human (acting as the reflector) can be located at various distances from the tunnel face; this factor was included in the analyzed geometrical model. Based on the modeling results of different thickness coal seams (2, 3, 4, 5, 6, 7, 8m), conclude that a radar wave reflected from a human body can be reliably measured, when the distance between the human and the transducer is not exceed 8m.


Assuntos
Carvão Mineral , Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Modelos Teóricos , Radar , Geologia , Humanos
19.
Int J Mol Sci ; 21(7)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252223

RESUMO

Accumulated evidence suggests that binding kinetic properties-especially dissociation rate constant or drug-target residence time-are crucial factors affecting drug potency. However, quantitative prediction of kinetic properties has always been a challenging task in drug discovery. In this study, the VolSurf method was successfully applied to quantitatively predict the koff values of the small ligands of heat shock protein 90α (HSP90α), adenosine receptor (AR) and p38 mitogen-activated protein kinase (p38 MAPK). The results showed that few VolSurf descriptors can efficiently capture the key ligand surface properties related to dissociation rate; the resulting models demonstrated to be extremely simple, robust and predictive in comparison with available prediction methods. Therefore, it can be concluded that the VolSurf-based prediction method can be widely applied in the ligand-receptor binding kinetics and de novo drug design researches.

20.
J Cosmet Dermatol ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32227574

RESUMO

BACKGROUND: To evaluate the orbital involvement epidemiology in facial fractures, the clinical distribution and effects of orbital involvement in these patients, the frequency and nature of treatment procedures performed for these involvements, and the immediate- and intermediate-term effects of these treatment procedures. METHODS: Two hundred patients with hard tissue maxillofacial injuries were included in this study. Clinical examination was performed in-depth. Images were taken to determine and confirm clinical observations and to finalize treatment modality. Orbital involvement in patients was noted as present or absent. The clinical effects and features in postoperative imaging studies were noted until 3 months after trauma in each patient. RESULTS: Out of 200 patients, about one-third patients (58;29%) had orbital involvement and out of which 49 were males. Regarding clinical-radiological signs in orbit involved fractures, the incidences were variable, that is, periorbital ecchymosis (77.6%), periorbital edema (74.1%), subconjunctival hemorrhage (67.2%), palpable step/crepitus in orbital rim (62.1%), infraorbital nerve paresthesia (46.6%), restricted globe movement (5.2%), orbital rim discontinuity/step (72.4%), maxillary sinuses (51.7%), orbital wall/floor/roof rupture (55.2%), and infraorbital foramen involvement (36.2%). Palpable step/crepitus in orbital rim was recovered remarkably earlier in patients of open reduction internal fixation (ORIF) group, and features of restricted globe movements, orbital rim discontinuity/step, orbital wall/floor/roof rupture, and infraorbital foramen involvement in patients were recovered immediately after open reduction and internal fixation treatment. CONCLUSION: Early repair of the maxillofacial injuries with orbital involvement has better functional and esthetic outcome.

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