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1.
Behav Neurol ; 2021: 9417173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795804

RESUMO

Methods: Patients with stroke were compared and correlated from overall and three periods (1-3 months, 4-6 months, and >6 months). Fugl-Meyer assessment for the upper extremity (FMA-UE) and action research and arm test (ARAT) were used to compare the UE motor status between patients with PSA and without PSA through a cross-sectional study among 435 patients. Then, the correlations between the evaluation scale scores of UE motor status and language function of patients with PSA were analyzed in various dimensions, and the language subfunction most closely related to UE motor function was analyzed by multiple linear regression analysis. Results: We found that the scores of FMA-UE and ARAT in patients with PSA were 14 points ((CI) 10 to 18, p < 0.001) and 11 points lower ((CI) 8 to 13, p < 0.001), respectively, than those without PSA. Their FMA-UE (r = 0.70, p < 0.001) and ARAT (r = 0.62, p < 0.001) scores were positively correlated with language function. Regression analysis demonstrated that spontaneous speech ability may account for UE motor function (R 2 = 0.51, p < 0.001; R 2 = 0.42, p < 0.001). Consistent results were also obtained from the analyses within the three time subgroups. Conclusion: Stroke patients with PSA have worse UE motor performance. UE motor status and language function showed positive correlations, in which spontaneous speech ability significantly accounts for the associations.


Assuntos
Afasia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estudos Transversais , Avaliação da Deficiência , Humanos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Extremidade Superior
2.
Pathogens ; 10(11)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34832680

RESUMO

Common root rot, caused by Bipolaris sorokiniana, is one of the most prevalent diseases of wheat and has led to major declines in wheat yield and quality worldwide. Here, strain XZ34-1 was isolated from soil and identified as Bacillus amyloliquefaciens based on the morphological, physiological, biochemical characteristics and 16S rDNA sequence. Culture filtrate (CF) of strain XZ34-1 showed a high inhibition rate against B.sorokiniana and had a broad antifungal spectrum. It also remarkably inhibited the mycelial growth and spore germination of B. sorokiniana. In pot control experiments, the incidence and disease index of common root rot in wheat seedlings were decreased after treatment with CF, and the biological control efficacy was significant, up to 78.24%. Further studies showed XZ34-1 could produce antifungal bioactive substances and had the potential of promoting plant growth. Lipopeptide genes detection with PCR indicated that strain XZ34-1 may produce lipopeptides. Furthermore, activities of defense-related enzymes were enhanced in wheat seedlings after inoculation with B.sorokiniana and treatment with CF, which showed induced resistance could be produced in wheat to resist pathogens. These results reveal that strain XZ34-1 is a promising candidate for application as a biological control agent against B.sorokiniana.

4.
J Chem Phys ; 155(5): 054305, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364348

RESUMO

Atomically precise metal nanoclusters, especially the metal nanoclusters with an exotic core structure, have given rise to a great deal of interest in catalysis, attributing to their well-defined structures at the atomic level and consequently unique electronic properties. Herein, the catalytic performances of three gold nanoclusters, such as Au38S2(S-Adm)20 with a body-centered cubic (bcc) kernel structure, Au30(S-Adm)18 with a hexagonal close-packed (hcp) core structure, and Au21(S-Adm)15 with a face-centered cubic (fcc) kernel structure, were attempted for the CO2 cycloaddition with epoxides toward cyclic carbonates. Due to the excess positive charge with a strong Lewis acidity and large chemical adsorption capacity, the bcc-Au38S2(S-Adm)20 nanocluster outperformed the hcp-Au30(S-Adm)18 and fcc-Au21(S-Adm)15 nanoclusters. Additionally, the synergistic effect between the gold nanocluster and co-catalyst played a crucial role in CO2 cycloaddition.

5.
J Cell Mol Med ; 25(19): 9102-9111, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34432370

RESUMO

Retinal pigment epithelial (RPE) cells are the major cell type in the epi- or sub-retinal membranes in the pathogenesis of proliferative vitreoretinopathy (PVR), which is a blinding fibrotic eye disease and still short of effective medicine. The purpose of this study is to demonstrate whether Chalocomoracin (CMR), a novel purified compound from fungus-infected mulberry leaves, is able to inhibit vitreous-induced signalling events and cellular responses intrinsic to PVR. Our studies have revealed that the CMR IC50 for ARPE-19 cells is 35.5 µmol/L at 72 hours, and that 5 µmol/L CMR inhibits vitreous-induced Akt activation and p53 suppression; in addition, we have discovered that this chemical effectively blocks vitreous-stimulated proliferation, migration and contraction of ARPE-19 cells, suggesting that CMR is a promising PVR prophylactic.

6.
Exp Cell Res ; 406(1): 112735, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265287

RESUMO

Tripartite motif containing 16 (TRIM16) is a member of the tripartite motif protein family and functions as a potential tumor suppressor in several cancers. However, the specific function and clinical significance of TRIM16 in colorectal cancer (CRC) remains unclear. In this study, we observed that low TRIM16 expression was detected frequently in primary colorectal cancer (CRC) tissues and was closely associated with a better prognosis. Functional studies demonstrate that TRIM16 overexpression notably inhibits the metastasis abilities of CRC in vivo and in vitro. Mechanistically, our results demonstrated that TRIM16 directly bound and ubiquitinated Snail family transcriptional repressor 1 (Snail), an important transcriptional factor of the epithelial-mesenchymal transition (EMT) process suppressing the EMT in CRC. Additionally, our data revealed that the inhibition effect of TRIM16 on cancer metastasis was dependent on Snail degradation. Collectively, our study is the first to report that TRIM16 plays a crucial anti-tumor role in CRC tumorigenesis. We also provided novel evidence that TRIM16 might act as a prognostic and therapeutic target to assess and inhibit CRC progression.


Assuntos
Carcinoma/genética , Neoplasias Colorretais/genética , Neoplasias Hepáticas/genética , Fatores de Transcrição da Família Snail/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma/metabolismo , Carcinoma/mortalidade , Carcinoma/secundário , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Proteólise , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Análise de Sobrevida , Proteínas com Motivo Tripartido/antagonistas & inibidores , Proteínas com Motivo Tripartido/metabolismo , Carga Tumoral , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
7.
Microb Biotechnol ; 14(4): 1827-1838, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34173722

RESUMO

Discovering new serological markers of Mycobacterium tuberculosis (MTB) infection and establishing a rapid and efficient detection technology is of great significance for the prevention and control of tuberculosis. In this study, we established an exponentially modified protein abundance index (emPAI) value-assisted strategy to investigate and improve the screening efficiency of serological biomarkers of tuberculosis. First, we used LC-MS/MS to analyse MTB culture filtrate proteins (MTB-CFPs), and 632 MTB proteins were identified. Then, the characteristic values of MTB-CFPs - including emPAI value, molecular weight (Mw), isoelectric point (pI), grand average of hydropathy (GRAVY), transmembrane domain (TMD) and functional groups were calculated. Next, we successfully prepared 10 MTB proteins with emPAI value > 1.0 and recombinantly expressed these proteins in Escherichia coli. At the same time, 3 MTB proteins with emPAI between 0.1 and 0.5 were randomly selected as the control groups, and the immunogenicity of the recombinant MTB proteins was detected using ELISA. The sensitivity and receiver operating characteristic (ROC) curves were calculated for each recombinant MTB protein. The results showed that the areas under the curve (AUC) value of Rv2031c, Rv0577, Rv0831c, Rv0934 and Rv3248c were all higher than those of Rv3875 (AUC, 0.6643). Further analysis of the relationship between emPAI value and antibody sensitivity, AUC value and antibody affinity in mice immunized with recombinant MTB protein showed that emPAI values were positively correlated with them, and R-squared value ranged from 0.64 to 0.79. The only exception was ESAT-6 (encoded by the Rv3875 gene), which AUC value was relatively low owing to its strong immunosuppressive properties. This study provides a rationale for the serological marker screening of emPAI-assisted tuberculosis clinical test. The results also provide new technical support for the screening of candidate serological markers of infectious diseases in the future.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Animais , Antígenos de Bactérias , Proteínas de Bactérias/genética , Biomarcadores , Cromatografia Líquida , Camundongos , Mycobacterium tuberculosis/genética , Espectrometria de Massas em Tandem , Tuberculose/diagnóstico
8.
Front Endocrinol (Lausanne) ; 12: 609134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025574

RESUMO

Background: Berberine is a plant alkaloid that has multiple beneficial effects against intestine inflammation. In our previous study, we have found that berberine also possesses an antidiabetic effect. However, whether berberine is useful in the prevention of type 2 diabetes mellitus (T2DM) through its effect on intestine endocrine function and gut microbiota is unclear. Aim: To investigate the effects of berberine in the prevention of T2DM, as well as its effects on intestine GLP-2 secretion and gut microbiota in ZDF rats. Methods: Twenty Zucker Diabetic Fatty (ZDF) rats were fed a high-energy diet until they exhibited impaired glucose tolerance (IGT). The rats were then divided into two groups to receive berberine (100 mg/kg/d; berberine group) or vehicle (IGT group) by gavage for 3 weeks. Five Zucker Lean (ZL) rats were used as controls. Fasting blood glucose (FBG) was measured, an oral glucose tolerance test was performed, and the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) was calculated. Intestinal expression of TLR-4, NF-κB, TNF-α, mucin, zona occludens-1 (ZO-1) and occludin were assessed (immunohistochemistry). Plasma levels and glutamine-induced intestinal secretion of glucagon-like peptide-1 (GLP-1) and GLP-2 were measured (enzyme-linked immunosorbent assay). The plasma lipopolysaccharide (LPS) level was measured. Fecal DNA extraction, pyrosequencing, and bioinformatics analysis were performed. Results: After 3 weeks of intervention, diabetes developed in all rats in the IGT group, but only 30% of rats in the berberine group. Treatment with berberine was associated with reductions in food intake, FBG level, insulin resistance, and plasma LPS level, as well as increases in fasting plasma GLP-2 level and glutamine-induced intestinal GLP-2 secretion. Berberine could increase the goblet cell number and villi length, and also reverse the suppressed expressions of mucin, occludin, ZO-1 and the upregulated expressions of TLR-4, NF-κB and TNF-α induced in IGT rats (P<0.05). Berberine also improved the structure of the gut microbiota and restored species diversity. Conclusion: Berberine may slow the progression of prediabetes to T2DM in ZDF rats by improving GLP-2 secretion, intestinal permeability, and the structure of the gut microbiota.

9.
J Pept Sci ; 27(9): e3337, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33987904

RESUMO

Antimicrobial peptide L163 was computationally designed by our laboratory; L163 is active against multidrug-resistant (MDR) bacteria but is easily degraded in the plasma and by trypsin. Amino acid substitution, cyclization, and amino-terminal (N-terminal) acetylation were performed to obtain L163 analogs with high stability in the plasma and in trypsin solutions. The stability, antimicrobial activity, and biosafety of L163 and its analogs were investigated. Comparison with unmodified L163 indicated that N-terminal acetylation enhanced the stability against pH, plasma, and trypsin degradation, and phenylalanine (Phe) substitution for leucine (Leu) and cysteine bridge (S-S) cyclization decreased the stability. N-terminal acetylation also enhanced antimicrobial activity against MDR Streptococcus Sc181, Listeria monocytogenes, and Enterococcus E1478F; did not change the activity against MDR Staphylococcus aureus 9, Staphylococcus sciuri P254, and Staphylococcus aureus RN4220; and decreased the activity against Candida tropicalis, Candida albicans, and Enterococcus faecalis Fbc35. Phe substitution for Leu and S-S cyclization decreased the antimicrobial activity. The negative effect of these modifications was detected against biofilm formation by the tested microbial strains. Comparison of Phe substitution for Leu and S-S cyclization indicated that N-terminally acetylated L163 (L163-Ac) is the best candidate. L163-Ac peptide had the highest antibacterial activity and enhanced tolerance to temperature, pH, plasma, and trypsin and low toxicity.

10.
Biochem J ; 478(10): 1907-1919, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33955460

RESUMO

Antimicrobial peptides (AMPs) are conventional antibiotic alternatives due to their broad-spectrum antimicrobial activities and special mechanisms of action against pathogens. The antifungal peptide CGA-N12 was originally derived from human chromogranin A (CGA) and consists of the 65th to 76th amino acids of the CGA N-terminal region. In the present study, we found that CGA-N12 had fungicidal activity and exhibited time-dependent inhibition activity against Candida tropicalis. CGA-N12 entered the cells to exert its antagonist activity. The internalization of CGA-N12 was energy-dependent and accompanied by actin cytoskeleton-, clathrin-, sulfate proteoglycan-, endosome-, and lipid-depleting agent-mediated endocytosis. Moreover, the CGA-N12 internalization pathway was related to the peptide concentration. The effects of CGA-N12 on the cell membrane were investigated. CGA-N12 at a low concentration less than 4 × MIC100 did not destroy the cell membrane. While with increasing concentration, the damage to the cell membrane caused by CGA-N12 became more serious. At concentrations greater than 4 × MIC100, CGA-N12 destroyed the cell membrane integrity. Therefore, the membrane activity of CGA-N12 is concentration dependant.


Assuntos
Antifúngicos/farmacologia , Candida tropicalis/efeitos dos fármacos , Membrana Celular/metabolismo , Cromogranina A/metabolismo , Endocitose , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Transporte Biológico , Cálcio/metabolismo , Candida tropicalis/crescimento & desenvolvimento , Membrana Celular/efeitos dos fármacos , Humanos
11.
Chem Soc Rev ; 50(9): 5590-5630, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33690780

RESUMO

Catalytic non-oxidative direct dehydrogenation of light alkanes serves as an effective reinforcement to selectively produce the corresponding olefins, and the heterogeneous metals and metal oxides, not limited to the commercially used Pt- and Cr-based catalysts, are widely investigated to enhance the efficiency. In this review, we outline the progress of these dehydrogenation catalysts that have been mainly developed in the past five years. For different classes of the most-promising catalysts in the selective dehydrogenation of ethane-to-ethylene and propane-to-propylene, their syntheses, structural information, catalytic properties and mechanisms are comparatively summarized.

12.
Subst Use Misuse ; 56(6): 801-807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33754934

RESUMO

BACKGROUND: It is well-documented that heroin users demonstrate aberrant emotion-processing abilities. However, the mechanism by which heroin users process emotional information after it has captured their attention and entered their working memory is unclear. OBJECTIVES: A modified emotional 2-back task was used to examine whether heroin abstainers demonstrate specific bias patterns in updating emotional stimuli in their working memory. METHODS: In total, 26 male heroin abstainers and 29 healthy controls were asked to identify whether the current picture was the same as a picture that had appeared two trials earlier, while behavioral data and electroencephalogram data were collected. RESULTS: Contrary to predictions, the heroin abstainers and healthy controls demonstrated a similar pattern of P300 activity in response to emotional stimuli with no between-group differences in accuracy or reaction time. More specifically, the P300 amplitudes were larger for negative pictures than for positive and neutral pictures. Surprisingly, we found larger P300 amplitudes at Fz electrodes than at Cz and Pz electrodes in the control group, whereas there was no significant difference at midline electrodes in the heroin abstainers. CONCLUSIONS/IMPORTANCE: Although subtle differences may exist in attentional engagement toward incoming emotional stimulus between two groups, the similar P300 pattern may indicate partial preservation of emotional working memory capacity associated with adaptive emotion regulation in heroin abstainers. These results deepen our understanding of the emotion regulation impairments associated with chronic drug use.


Assuntos
Heroína , Memória de Curto Prazo , Emoções , Potenciais Evocados , Humanos , Masculino , Tempo de Reação
13.
Methods ; 194: 65-74, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33774156

RESUMO

Base editing technology is an efficient tool for genome editing, particularly in the correction of base mutations. Diverse base editing systems were developed according to the dCas9 or nCas9 linked with different deaminase or reverse transcriptase in the editors, including ABEs, CBEs, PEs and dual-functional of base editor (such as CGBE1, A&C-BEmax, ACBE, etc.). Currently, Base editing technology has been widely applied to various fields such as microorganisms, plants, animals and medicine for basic research and therapeutics. Here, we reviewed the advancement of base editing technology. We also discussed the application of base editors in different areas in the future.

14.
Methods ; 194: 3-11, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33705859

RESUMO

The technology of clustered regularly interspaced short palindromic repeats (CRISPR)-associated nuclease Cas9 (CRISPR-Cas9) is a powerful system for protein depletion resulting from insertions and deletions following Cas9 cleavage of genome at specific site in vitro and in vivo. We herein present a relatively standard protocol for protein depletion in a step-by-step procedure, including guide RNA designation and vector construction, lentivirus production, cell selection, and experimentally validate the function of targeted protein. We exemplified this approach by editing PDGFRß in human epithelial cells, and expected that this simplified and detailed protocol will be more broadly applied on specific genes to aid understanding gene functions.

15.
J Cell Mol Med ; 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33611845

RESUMO

In this study, we investigated how Roux-en-Y gastric bypass (RYGB) enhances glucagon-like peptide 1 (GLP-1) response in GK rats and explored the potential link between RYGB-stimulated BAs/FXR signalling and GLP-1R-linked signalling in ß-cells, a key pathway that regulates glucose-stimulated insulin secretion (GSIS). Here we show that RYGB restores GLP-1R expression in GK rat islets. This involves increased total BAs as well as chenodeoxycholic acid (CDCA), leading to FXR activation, increasing FXR binding to the promoter of Glp-1r and enhancing occupancy of histone acetyltransferase steroid receptor coactivator-1 (SRC1), thus increasing histone H3 acetylation at the promoter. These coordinated events bring about increased GLP-1R expression, resulting in greater GLP-1 response in ß-cells. Moreover, ablation of FXR suppressed the stimulatory effects of GLP-1. Thus, this study unravels the crucial role of the BAs/FXR/SRC1 axis-controlled GLP-1R expression in ß-cells, which results in enhanced incretin effect and normalized blood glucose of GK rats after RYGB.

16.
J Phys Chem A ; 125(3): 777-794, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33433218

RESUMO

To investigate the effect of polymerization (n = 1, 2, 3, and 4) on the charge-transfer (CT) mechanisms in the one (two)-photon absorption (OPA and TPA) process of D-A-type triphenylamine derivatives, charge density difference is used to graphically represent the CT characteristics. A transition density matrix is utilized to reveal the direction of CT on different groups quantitatively. With the n increasing, electrons are mainly transferred between the groups in the middle position of the molecular chain during OPA and TPA processes. Simulated results show that the energy gap and excitation energy have a good linear relationship with the reciprocal of the polymerization degree. Importantly, the polymerization effect can effectively increase the electronic transmission capability, TPA performance, and second hyperpolarizability. Besides, the simplified sum over state model reveals the variation factor of the TPA cross-section and the second static hyperpolarizability. The McRae formula and Bakhshiev formula are used to estimate the difference of dipole moments, which is an important parameter of the second hyperpolarizability. The comprehensive analysis of the nonlinear optical (NLO) parameters of triphenylamine derivatives can provide some significant guidance for molecular design and improve the NLO performance of D-A molecular materials. Also, the thermodynamic parameters can provide some theoretical supports for solving practical problems.

17.
Diabetes Metab Res Rev ; 37(4): e3432, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33400837

RESUMO

AIMS: Urinary haptoglobin (UHp) is a potential biomarker for predicting progress of diabetic kidney disease (DKD) to remedy the defects of currently used urinary albumin. The clinical application of UHp is however limited, owing to the extremely low level in urine. This study aims to establish an enzyme-linked immunosorbent assay (ELISA) kit specifically for detecting UHp in urine samples of patients with diabetes and DKD. MATERIALS AND METHODS: Supersensitive human haptoglobin antibodies were generated for ELISA kit development, and the sensitivity, specificity and reproducibility of the kit was evaluated. This kit was used to detect UHp in 246 healthy individuals and 83 patients with type 2 diabetes (T2D). The interference of blood haptoglobin genotypes on UHp measurement was analysed. RESULTS: The UHp ELISA kit had a standard curve ranging from 5 to 200 ng/ml. The low detection limit was 0.11 ng/ml. The coefficients of variation of intra- and interassay were 5.5% and 8.3%, respectively. The kit showed high accuracy with 100.9% mean recovery rate, and linearity R2  = 0.999. The reference range of UHp was 0-42.3 ng/g creatinine (0-Q95) in the healthy individuals. UHp level was significantly higher in T2D patients with microalbuminuria and macroalbuminuria than that in T2D without microalbuminuria (p < 0.01). The UHp concentration measured by this kit was not affected by haptoglobin genotypes. CONCLUSIONS: We have generated an ELISA kit to accurately detect UHp levels, which is potentially a reliable biomarker of DKD.

18.
Biomed Pharmacother ; 133: 110999, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33227710

RESUMO

Abnormal angiogenesis is associated with intraocular diseases such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, and current therapies for these eye diseases are not satisfactory. The purpose of this study was to determine whether capilliposide B (CPS-B), a novel oleanane triterpenoid saponin derived from Lysimachia capillipes Hemsl, can inhibit vascular endothelial growth factor (VEGF)-induced angiogenesis signaling events and cellular responses in primary human retinal microvascular endothelial cells (HRECs). Our study revealed that the capilliposide B IC50 for HRECs was 8.5 µM at 72 h and that 1 µM capilliposide B specifically inhibited VEGF-induced activation of VEGFR2 and its downstream signaling enzymes Akt and Erk. In addition, we discovered that this chemical effectively blocked VEGF-stimulated proliferation, migration and tube formation of the HRECs, suggesting that capilliposide B is a promising prophylactic for angiogenesis-associated diseases such as proliferative diabetic retinopathy.


Assuntos
Indutores da Angiogênese/farmacologia , Inibidores da Angiogênese/farmacologia , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Saponinas/farmacologia , Triterpenos/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Microvasos/citologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Vasos Retinianos/citologia , Transdução de Sinais , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
19.
J Nanosci Nanotechnol ; 21(1): 392-404, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213639

RESUMO

The structure and fractal characteristics of nanopores of high-rank coal were investigated using an approach that integrates N2 adsorption and field emission scanning electron microscopy (FE-SEM). The results indicated that the high-rank coal of the Shanxi Formation has a complex pore-fracture network composed of organic matter pores, mineral-related pores, and microfractures. The pore type of high-rank coal tends to be complicated, and the main pore types are inkbottle pores and open pores, which are more conducive to methane enrichment. The Ro,max has a negative relationship with the total pore volume. In addition, the ash and inertinite contents show a positive correlation with the average pore size (APS), while the fixed carbon content exhibits a negative relationship with the APS. The pore structure of high-rank coal is controlled not only by the degree of metamorphism but also by coal composition, which leads to the variation in pore structure becoming more complicated. With the increase in coal metamorphism, high-rank coal with high amounts of fixed carbon content generally possesses a higher irregularity in pore structure. No obvious relationship was observed between D2 and the coal components, which indicates that the pore structure, ash content, moisture content and other factors controlled by the metamorphism of coal have different effects on D2 that lead to this inapparent relationship. A negative relationship exists between adsorption volume and D1, which indicates that the high irregularity of the pore structure is not conducive to methane absorption and that no obvious correlation exists between the adsorption volume and D2. In the high-rank coal, the high D1 value represents the complexity and heterogeneity of the pore structure and represents a low adsorption affinity for methane molecules; in addition, D2 has no effect on the methane adsorption capacity.

20.
J Nanosci Nanotechnol ; 21(1): 741-749, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213675

RESUMO

The nanopore network in organic-rich shale plays a key role in shale gas storage and migration, and micropores are an important structural unit in connecting the migration channel. In this study, we selected six non-marine coal-bearing shales from the Qinshui Basin to investigate the effect of composition on micropore structure using X-ray diffraction, total organic carbon (TOC), vitrinite reflectance, and CO2 adsorption methods. The results indicate that non-marine shale with higher TOC content possesses more micropores, leading to a more complex pore structure and improving the heterogeneity of shale reservoirs. With the increase in TOC content, the micropore surface area and micropore volume clearly increases, which greatly improves the gas storage space in shale reservoirs. The thermal evolution of organic matter promotes the development of micropores to a certain extent in non-marine shale. Clay minerals possess a rough surface and develop more micropores, and their influence on the micropore structure of non-marine shale is relatively strong, while terrestrial quartz exhibits significant micropore development. The obviously positive correlations between micropore volume and kaolinite, chlorite contents in the non-marine shale suggest that kaolinite and chlorite make a certain contribution to micropore volume. The characteristics of micropore structures in coal mainly depend on lithotypes, TOC content, and ash content, while clay content, quartz content, and TOC content are the key factors controlling the formation of micropores in non-marine shale.

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