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1.
Plant Physiol ; 192(1): 666-679, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36881883

RESUMEN

The active structural change of actin cytoskeleton is a general host response upon pathogen attack. This study characterized the function of the cotton (Gossypium hirsutum) actin-binding protein VILLIN2 (GhVLN2) in host defense against the soilborne fungus Verticillium dahliae. Biochemical analysis demonstrated that GhVLN2 possessed actin-binding, -bundling, and -severing activities. A low concentration of GhVLN2 could shift its activity from actin bundling to actin severing in the presence of Ca2+. Knockdown of GhVLN2 expression by virus-induced gene silencing reduced the extent of actin filament bundling and interfered with the growth of cotton plants, resulting in the formation of twisted organs and brittle stems with a decreased cellulose content of the cell wall. Upon V. dahliae infection, the expression of GhVLN2 was downregulated in root cells, and silencing of GhVLN2 enhanced the disease tolerance of cotton plants. The actin bundles were less abundant in root cells of GhVLN2-silenced plants than in control plants. However, upon infection by V. dahliae, the number of actin filaments and bundles in the cells of GhVLN2-silenced plants was raised to a comparable level as those in control plants, with the dynamic remodeling of the actin cytoskeleton appearing several hours in advance. GhVLN2-silenced plants exhibited a higher incidence of actin filament cleavage in the presence of Ca2+, suggesting that pathogen-responsive downregulation of GhVLN2 could activate its actin-severing activity. These data indicate that the regulated expression and functional shift of GhVLN2 contribute to modulating the dynamic remodeling of the actin cytoskeleton in host immune responses against V. dahliae.


Asunto(s)
Ascomicetos , Verticillium , Gossypium/metabolismo , Resistencia a la Enfermedad/genética , Actinas/metabolismo , Calcio/metabolismo , Verticillium/fisiología , Ascomicetos/metabolismo , Citoesqueleto de Actina/metabolismo , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo
2.
Glob Chang Biol ; 30(1): e17114, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273577

RESUMEN

Human activity and climate change affect biodiversity and cause species range shifts, contractions, and expansions. Globally, human activities and climate change have emerged as persistent threats to biodiversity, leading to approximately 68% of the ~522 primate species being threatened with extinction. Here, we used habitat suitability models and integrated data on human population density, gross domestic product (GDP), road construction, the normalized difference vegetation index (NDVI), the location of protected areas (PAs), and climate change to predict potential changes in the distributional range and richness of 26 China's primate species. Our results indicate that both PAs and NDVI have a positive impact on primate distributions. With increasing anthropogenic pressure, species' ranges were restricted to areas of high vegetation cover and in PAs surrounded by buffer zones of 2.7-4.5 km and a core area of PAs at least 0.1-0.5 km from the closest edge of the PA. Areas with a GDP below the Chinese national average of 100,000 yuan were found to be ecologically vulnerable, and this had a negative impact on primate distributions. Changes in temperature and precipitation were also significant contributors to a reduction in the range of primate species. Under the expected influence of climate change over the next 30-50 years, we found that highly suitable habitat for primates will continue to decrease and species will be restricted to smaller and more peripheral parts of their current range. Areas of high primate diversity are expected to lose from 3 to 7 species. We recommend that immediate action be taken, including expanding China's National Park Program, the Ecological Conservation Redline Program, and the Natural Forest Protection Program, along with a stronger national policy promoting alternative/sustainable livelihoods for people in the local communities adjacent to primate ranges, to offset the detrimental effects of anthropogenic activities and climate change on primate survivorship.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Animales , Humanos , Primates , Biodiversidad , Ecosistema , Actividades Humanas , China
3.
Angew Chem Int Ed Engl ; 63(5): e202317402, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38078790

RESUMEN

The pursuit of synthetic receptors with high binding affinities has long been a central focus in supramolecular chemistry, driven by their significant practical relevance in various fields. Despite the numerous synthetic receptors that have been developed, most exhibit binding affinities in the micromolar range or lower. Only a few exceptional receptors achieve binding affinities exceeding 109  M-1 , and their substrate scopes remain rather limited. In this context, we introduce SC[5]A, a conjugated corral-shaped macrocycle functionalized with ten sulfate groups. Owing to its deep one-dimensional confined hydrophobic cavity and multiple sulfate groups, SC[5]A displays an extraordinarily high binding strength of up to 1011  M-1 towards several size-matched, rod-shaped organic dications in water. Besides, its conformation exhibits good adaptability, allowing it to encapsulate a wide range of other guests with diverse molecular sizes, shapes, and functionalities, exhibiting relatively strong affinities (Ka =106 -108  M-1 ). Additionally, we've explored the preliminary application of SC[5]A in alleviating blood coagulation induced by hexadimethrine bromide in vitro and in vivo. Therefore, the combination of ultrahigh binding affinities (towards complementary guests) and adaptive recognition capability (towards a wide range of functional guests) of SC[5]A positions it as exceptionally valuable for numerous practical applications.

4.
Drug Metab Rev ; 55(1-2): 94-106, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36453523

RESUMEN

At present, receptor tyrosine kinase signaling-related pathways have been successfully mediated to inhibit tumor proliferation and promote anti-angiogenesis effects for cancer therapy. Tyrosine kinase inhibitors (TKIs), a group of novel chemotherapeutic agents, have been applied to treat diverse malignant tumors effectively. However, the latent toxic and side effects of TKIs, such as hepatotoxicity and cardiotoxicity, limit their use in clinical practice. Metabolic activation has the potential to lead to toxic effects. Numerous TKIs have been demonstrated to be transformed into chemically reactive/potentially toxic metabolites following cytochrome P450-catalyzed activation, which causes severe adverse reactions, including hepatotoxicity, cardiotoxicity, skin toxicity, immune injury, mitochondria injury, and cytochrome P450 inactivation. However, the precise mechanisms of how these chemically reactive/potentially toxic species induce toxicity remain poorly understood. In addition, we present our viewpoints that regulating the production of reactive metabolites may decrease the toxicity of TKIs. Exploring this topic will improve understanding of metabolic activation and its underlying mechanisms, promoting the rational use of TKIs. This review summarizes the updated evidence concerning the reactive metabolites of TKIs and the associated toxicities. This paper provides novel insight into the safe use of TKIs and the prevention and treatment of multiple TKIs adverse effects in clinical practice.


Asunto(s)
Activación Metabólica , Humanos , Cardiotoxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Inhibidores de Proteínas Quinasas/efectos adversos , /metabolismo
5.
Mol Biol Rep ; 50(1): 299-308, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36331747

RESUMEN

BACKGROUND: Kazal-type serine protease inhibitors play a role in physiological processes such as blood coagulation and fibrinolysis. The amino acid residues at the P1 site are different, and they inhibit different types of proteases. The inhibitory mechanism of the protease in the salivary glands of Poecilobdella manillensis is still unclear. METHODS AND RESULTS: Based on cloning, prokaryotic expression and bioinformatics analysis, we studied the role of Kazal-type serine protease inhibitors in P. manillensis and analyzed their expression by quantitative real-time PCR. The results suggested that the recombinant protein was successfully expressed in the supernatant when a prokaryotic expression vector was constructed and induced with 0.2 mmol/L IPTG at 37 °C for 4 h, and the enzymatic activity was determined. The mature protein encodes 91 amino acids and has a relative molecular weight of 9929.32 Da, and after removing the signal peptide, the theoretical isoelectric point was 8.79. It is an unstable protein without a transmembrane domain. The mature protein contains two Kazal-type domains, in which all P1 residues are Lys, consisting of an α helix and three antiparallel ß sheets. The upregulated expression of the mRNA was induced after a meal was provided, and the results showed an increasing and then decreasing trend. CONCLUSIONS: Taken together, the results indicate that mature proteins from P. manillensis inhibit thrombin activity, laying the foundation for the subsequent in-depth study of the function of genes encoding Kazal-type serine protease inhibitors.


Asunto(s)
Inhibidores de Serina Proteinasa , ADN Complementario/genética , Proteínas Recombinantes/genética , Dominios Proteicos , Inhibidores de Serina Proteinasa/genética , Clonación Molecular
6.
Macromol Rapid Commun ; 44(11): e2200778, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36404104

RESUMEN

Covalent organic frameworks (COFs) are a type of crystalline porous polymers that possess ordered structures and eternal pores. Because of their unique structural characteristics and diverse functional groups, COFs have been used in various application fields, such as adsorption, catalysis, separation, ion conduction, and energy storage. Among COFs, the fluorine-containing COFs (fCOFs) have been developed for special applications by virtue of special physical and chemical properties resulting from fluorine element, which is a nonmetallic halogen element and possesses strong electronegativity. In the organic chemistry field, introducing fluorine into chemicals enables those chemicals to exhibit many interesting properties, and fluorine chemistry increasingly plays an important role in the history of chemical development. The introduction of fluorine in COFs can enhance the crystallinity, porosity, and stability of COFs, making COFs having superior performances and some new applications. In this review, the synthesis and application of fCOFs are systematically summarized. The application involves photocatalytic production of hydrogen peroxide, photocatalytic water splitting, electrocatalytic CO2 reduction, adsorption for different substances (H2 , pesticides, per-/polyfluoroalkyl substances, polybrominated diphenyl ethers, bisphenols, and positively charged organic dye molecules), oil-water separation, energy storage (e.g., zinc-ion batteries, lithium-sulfur batteries), and proton conduction. Perspectives of remaining challenges and possible directions for fCOFs are also discussed.


Asunto(s)
Flúor , Estructuras Metalorgánicas , Halógenos , Polímeros
7.
Am J Primatol ; 85(6): e23493, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37056028

RESUMEN

Predicting the spatial distribution of species and suitable areas under global climate change could provide a reference for species conservation and long-term management strategies. Macaca thibetana and Macaca arctoides are two endangered species of Chinese macaques. However, limited information is available on their distribution, and their habitat needs lack proper assessment due to complicated taxonomy and less research attention. In recent years, scholars widely used the maximum entropy (MaxEnt) model to predict the impact of global climate and certain environmental factors on species distribution. Therefore, we used the MaxEnt model to predict the spatiotemporal distribution of both macaque species under six climate change scenarios using occurrence and high-resolution ecological data. We identified climatic factors, elevation, and land cover that shape their distribution range and determined shifts in their habitat range. The results demonstrated that temperature range, annual precipitation, forest land cover, and temperature seasonality, including the precipitation of the driest month are the main factors affecting their distribution. Currently, M. thibetana is mainly concentrated in central, eastern, southern, and southwestern China, and M. arctoides is mainly concentrated in three provinces (Yunnan, Guangxi, and Guangdong) in southern China. The MaxEnt model predicted that the suitable habitat for both species will increase with increased greenhouse emission scenarios. We also found that with the further increase in greenhouse emissions M. thibetana is expected to migrate to western China, and M. arctoides is expected to migrate to western or eastern China. This reinterpretation of the distribution of M. thibetana and M. arctoides in China, and predicted potential suitable habitat and possible migration direction, may provide new insights into the future conservation and management of these two species.


Asunto(s)
Cambio Climático , Macaca arctoides , Macaca , Animales , China , Ecosistema , Distribución Animal
8.
BMC Plant Biol ; 22(1): 311, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35761174

RESUMEN

BACKGROUND: The tradeoff between negative and positive interactions of facilitated species and facilitators may depend on the degree of resource availability in agroecosystems. However, the rhizospheric mechanisms driving trade-offs that occur along phosphorus (P) and water availability gradients have not yet been systematically clarified. We established three types of root isolation conditions (no barrier, nylon barrier and solid barrier) at different P and water addition levels to address the above issue in a maize-grass pea intercropping system. RESULTS: The total yield and biomass net effect (NE) and the relative interaction index (RII) were significantly higher than 0 under all environmental conditions, demonstrating that plant-plant interactions generated positive effects in the intercropping system. The maize yield and biomass RII were 0.029-0.095 and 0.018-0.066, respectively, which indicated that maize growth was constantly facilitated. However, the RII for grass pea yield and biomass exhibited a different trend in comparison with maize. It was higher than 0 (as the facilitated species) under low soil P and moisture conditions and transitioned to values lower than 0 (facilitator species) under high P and moisture conditions, which showed that the type and intensity of plant-plant interactions steadily shifted with the applied stressors. Direct interactions decreased the maize rhizospheric soil pH by 1.5% and 1.9% under Low-P conditions. Notably, the rhizospheric soil acid and alkaline phosphatase secretions of maize and grass pea increased by 17.4-27.4% and 15.3-27.7%, respectively, in P-deficient soils. These results show that plant-plant interactions can effectively relieve P stress by mineralizing organophosphorus in P-deficient soils. Furthermore, the above tendency became more pronounced under drought-stressed conditions. The nylon barrier partially restricted the exchange and utilization of available nutrients and decreased the total yield and biomass by 1.8-7.8% and 1.1-7.8%, respectively. The presence of a solid barrier completely restricted interspecific rhizospheric interactions and decreased the total yield and biomass by 2.1-13.8% and 1.6-15.7%, respectively. Phytate and KH2PO4 addition intensified asymmetric interspecific competition, and grass pea was consistently subjected to competitive pressures. CONCLUSION: Briefly, the tradeoff between facilitation and competition was driven by rhizospheric interactions, and the transition in the intensity and type of interaction was highly dependent on resource availability in a biologically diverse system.


Asunto(s)
Fabaceae , Fósforo , Agricultura/métodos , Grano Comestible , Nylons , Suelo , Agua , Zea mays/fisiología
9.
Bioorg Med Chem ; 74: 117067, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36272186

RESUMEN

PI3Ks and HDACs play essential roles in the occurrence and progression of leukemia. Herein, a series of novel pyrazin-2(1H)-one derivatives were rationally designed and synthesized as novel dual PI3K and HDAC inhibitors based on scaffold replacement and heterozygous strategies. Most of the target compounds showed potent inhibitory potency to PI3Kα and HDAC6. Especially, compound 9q displayed PI3Kα and HDAC6 inhibitory with IC50 values of 372 nM and 4.5 nM, and anti-proliferative activity against MV4-11 cells with IC50 value of 0.093 ± 0.012 µM. Further mechanistic studies revealed that 9q induced apoptosis, arrested the cell cycle in the G2/M phase, promoted the acetylation of α-tubulin, and blocked the PI3K/AKT/mTOR signal way in MV4-11 cells. All the results demonstrated that 9q was a promising lead candidate for further development of novel PI3K/HDAC dual inhibitors for leukemia treatment.


Asunto(s)
Antineoplásicos , Leucemia , Humanos , Inhibidores de Histona Desacetilasas/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Leucemia/tratamiento farmacológico , Diseño de Fármacos , Relación Estructura-Actividad , Ensayos de Selección de Medicamentos Antitumorales , Simulación del Acoplamiento Molecular
10.
Bioorg Chem ; 128: 106117, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36063752

RESUMEN

The bromodomain and extra-terminal (BET) bromodomains, particularly BRD4, have been identified as promising therapeutic targets in the treatment of many human disorders such as cancer. Coumarin is a highly privileged moiety for the development of novel anticancer drugs which has been identified in clinical trials for the treatment of various cancers. Herein, we modified BRD4i ABBV-075 with a coumarin ring and synthesized a novel series of coumarin derivatives as BRD4 inhibitors. Among them, the representative compound 27d showed excellent BRD4 inhibitory activities with an IC50 value of 99 nM in the TR-FRET assay. Compared with ABBV-075, compound 27d displayed a favorable cell proliferation inhibitory activity in solid tumors, such as MCF-7, HGC-27 and HepG-2. Further mechanism investigation illustrated that 27d-treatment resulted in G0/G1 phase arrest and promoted apoptosis of MCF-7 cells. Compound 27d also blocked colony formation in a concentration-dependent manner in McF-7 cell lines. As the downstream-protein of BRD4, the expression of c-Myc was decreased in a dose-dependent manner after the treatment of compound 27d. Moreover, compound 27d also exhibited good in vivo and in vitro metabolic stability. All the findings meaningfully make it as a promising lead compound for further drug development.


Asunto(s)
Antineoplásicos , Proteínas Nucleares , Proteínas de Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Cumarinas/farmacología , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Relación Estructura-Actividad , Factores de Transcripción
11.
Angew Chem Int Ed Engl ; 60(10): 5257-5261, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33251671

RESUMEN

Green production of NH3 , especially the Li-mediated electrochemical N2 reduction reaction (NRR) in non-aqueous solutions, is attracting research interest. Controversies regarding the NRR mechanism greatly impede its optimization and wide applications. To understand the electrocatalytic process, we treated Au coated carbon fibrous paper (Au/CP) as the model catalyst. In situ XRD confirmed the transformation of lithium intermediates during NRR. Au greatly improved electron transfer kinetics to catalyze metallic Li formation, and accordingly highly accelerated spontaneous NRR. The Faradaic efficiency of NRR on Au/CP reached 34.0 %, and NH3 yield was as high as 50 µg h-1 cm-2 . Our research shows that the key step of Li-mediated non-aqueous NRR is electrocatalytic Li reduction and offers a novel electrocatalyst design method for Li reduction.

12.
Bioorg Med Chem Lett ; 30(3): 126885, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31862411

RESUMEN

In order to explore novel Aurora kinase inhibitors, a series of novel 2,4-disubstituted pyrimidines were designed, synthesized and evaluated their in vitro anti-proliferative activities against a panel of cancerous cell lines (A549, HCT-116 and MCF-7). Among them, compound 12a showed the moderate to high anti-proliferative activities against A549 (IC50 = 12.05 ± 0.45 µM), HCT-116 (IC50 = 1.31 ± 0.41 µM) and MCF-7 (IC50 = 20.53 ± 6.13 µM) cells, as well as the Aurora A and Aurora B inhibitory activities with the IC50 values of 309 nM and 293 nM, respectively. Furthermore, compound 12a induced apoptosis by upregulated the pro-apoptotic proteins Bax and decreased the anti-apoptotic protein Bcl-xl in HCT-116 cells. Moreover, the molecular docking study showed that compound 12a had good binding modes with Aurora A and Aurora B and the bioinformatics prediction discovered that compound 12a exhibited good drug likeness using SwissADME. Taken together, these results indicated that 12a may be a potential anticancer compound that was worthy of further development as Aurora kinase inhibitor.


Asunto(s)
Aurora Quinasa A/antagonistas & inhibidores , Aurora Quinasa B/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Pirimidinas/química , Apoptosis/efectos de los fármacos , Aurora Quinasa A/metabolismo , Aurora Quinasa B/metabolismo , Sitios de Unión , Línea Celular Tumoral , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Estructura Terciaria de Proteína , Pirimidinas/metabolismo , Pirimidinas/farmacología , Relación Estructura-Actividad , Proteína X Asociada a bcl-2/metabolismo
13.
Bioorg Chem ; 105: 104427, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33161248

RESUMEN

Antioxidants have been the subject of intense research interest due to their numerous health benefits. In this work, a series of new conjugates of hydroxytyrosol and coumarin were synthesized and evaluated for their free radical scavenging, toxicity and antioxidant mechanism in vitro. The all target compounds 14a-t exhibited better radical scavenging activity than BHT, hydroxytyrosol, and coumarin in both DPPH radical and ABTS+ radical cation scavenging assays. The structure-activity relationships study indicated that the number and position of hydroxyl groups on the coumarin ring were vital to a good antioxidant capacity. Furthermore, the most promising compound 14q showed less toxicity in hemolysis assay and weaker antiproliferative effects than BHT against normal WI-38 and GES cells, and enhanced viability of H2O2-induced HepG2 cells. Additionally, 14q decreased the apoptotic percentage of HepG2 cells, reduced the ROS produce and LDH release, and improved GSH and SOD levels in H2O2-treated HepG2 cells. Lastly, 14q exhibited more stability than hydroxytyrosol in methanol solution. These results revealed that conjugations of hydroxytyrosol and coumarin show better antioxidant capacity, and are the efficacious approach to finding novel potential antioxidant.


Asunto(s)
Antioxidantes/farmacología , Cumarinas/farmacología , Alcohol Feniletílico/análogos & derivados , Antioxidantes/síntesis química , Antioxidantes/química , Apoptosis/efectos de los fármacos , Benzotiazoles/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cumarinas/química , Relación Dosis-Respuesta a Droga , Humanos , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/farmacología , Estructura Molecular , Alcohol Feniletílico/química , Alcohol Feniletílico/farmacología , Picratos/antagonistas & inhibidores , Especies Reactivas de Oxígeno/análisis , Especies Reactivas de Oxígeno/metabolismo , Relación Estructura-Actividad , Ácidos Sulfónicos/antagonistas & inhibidores
14.
Inorg Chem ; 56(15): 9321-9329, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28745894

RESUMEN

In the present work, a series of low-temperature firing scheelite structured microwave dielectric in water-insoluble La2O3-Nb2O5-V2O5 system was prepared via the traditional solid-state reaction method. Backscattering electron diffraction, X-ray diffraction (XRD), energy-dispersive analysis, and Rietveld refinements were performed to study the phase evolution and crystal structure. In the full composition range of (1 - x)LaNbO4-xLaVO4 (0 ≤ x ≤ 0.9) ceramics, at least four typical phase regions including monoclinic fergusonite, tetragonal sheelite, B-site ordered sheelite, and composite of monoclinic LaVO4 and tetragonal sheelite phases can be detected according to XRD analysis. The variations of relative dielectric constant εr, quality factor Q × f, and resonant frequency τf could be attributed to Nb/V-O bond ionicity, lattice energy, and the coefficient of thermal expansion. Infrared reflectivity spectra analysis revealed that ion polarization contributed mainly to the permittivity in microwave frequencies ranges. Furthermore, the 0.7LaNbO4-0.3LaVO4 ceramic sintered at 1160 °C possessed excellent microwave dielectric properties with an εr of ∼17.78, a Q × f of ∼75 940 GHz, and a τf of ca. -36.8 ppm/°C. This series of materials might be good candidate for microwave devices.

15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 39(3): 401-405, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28695813

RESUMEN

Objective To evaluate the value of acoustic radiation force impulse(ARFI)imaging in the diagnosis of early non-alcoholic steatohepatitis(NASH).Methods Totally 32 SD rats were randomly divided into high-fat diet group(n=24)and normal-diet group(n=8)by using the random number table. At the end of the 4th,8th,12th,and 16th week,six rats from the high-diet group and two rats from the normal-diet group were selected blindly for weighting,blood biochemical test,conventional ultrasound,and ARFI imaing. HE staining was used for pathological observation. Results None of the 32 rats developed liver fibrosis. Based on the pathological results,these rats were divided into M1 [mild-to-moderate simple fatty liver(SS)],M2(severe SS),M3(severe SS with early NASH),and C groups(normal control). Early NASH was seen only in the severe hepatic steatosis groups,and its distribution had a significant difference(P=0.006). The diagnostic accuracy of conventional ultrasound based on histological results was 34.4%(11/32). The ARFI value of M3 group was significantly lower than that of M2 group [(1.16±0.04)m/s vs.(1.22±0.05)m/s;t=2.301,P=0.04),and the low-density lipoprotein of M3 group was significantly higher than M2 group [(1.53±0.07)mmol/L vs.(1.21±0.22)mmol/L;t=3.075,P=0.01),while other clinical indicators had no statistical difference between these two groups. Conclusions The development of early NASH is associated with the severity of hepatic steatosis. ARFI value can provide important information to identify early NASH in patients with severe hepatic steatosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Animales , Dieta Alta en Grasa , Cirrosis Hepática , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
16.
Yi Chuan ; 38(8): 736-45, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27531612

RESUMEN

Peptidylprolyl isomerases (PPIase) cyclophilin A (CypA, encoded by PPIA) is a typical member of the Cyclophilin family and is involved in protein folding/translocation, signal transduction, inflammation, immune system regulation, apoptosis and virus replication. In the present study, we investigated the PPIase activity and genetic variation of vertebrate CypA. According to the GenBank reference sequences, vertebrate PPIA genes were cloned, among which the bat (Myotis davidi) and duck (Anas platyrhynchos) PPIA genes were reported for the first time. Then PPIA genes were sub-cloned into the expression vector pGEX-6p-1 and expressed in Escherichia coli. Recombinant CypA proteins were purified by using sepharose 4B affinity chromatography and the GST tag was cleaved, followed by gel filtration. The PPIase activity assay indicated that there was no significant difference in the catalytic activity of prolyl peptide bond isomerization among 12 different vertebrate CypA proteins. In addition, the genetic variation and molecular evolution analysis showed that these vertebrate CypA proteins had the same CsA binding site and the PPIase active sites. Furthermore, the predicted structure and gene localization were remarkable conserved. Our data suggested that the important residues of CypA were highly conserved, which is crucial for its PPIase activity and cellular functions.


Asunto(s)
Ciclofilina A/genética , Ciclofilina A/metabolismo , Isomerasa de Peptidilprolil/genética , Isomerasa de Peptidilprolil/metabolismo , Vertebrados/genética , Secuencia de Aminoácidos , Animales , Dominio Catalítico/genética , Clonación Molecular/métodos , Escherichia coli/genética , Evolución Molecular , Proteínas Recombinantes/genética , Alineación de Secuencia
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(4): 378-82, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27594147

RESUMEN

Objective To evaluate the role of ultrasound for thyroid nodules with atypia of undetermined significance(AUS).Methods From January 2014 to December 2015,83 thyroid nodules with AUS diagnosed by ultrasound-guided fine-needle aspiration biopsy were collected from 1984 subjects. On the basis of ultrasonic features,each thyroid nodule was prospectively classified into one of three categories: low suspicion for malignancy,intermediate suspicion for malignancy,and high suspicion for malignancy. Results Among 83 lesions,19 lesions(22.9%) were confirmed malignant,8 lesions (9.6%)were benign,56 lesions (67.5%)had no abnormal changes during clinical follow-up. The nodules were solitary in 36 cases (43.4%)and multiple in 47 cases(56.6%).The maximum diameter was (1.2±0.7)cm. Based on the ultrasonic feature of 19 malignant cases,16 cases (84.2%) were classified as high suspicion for malignancy,2 cases(10.5%) as intermediate suspicion for malignancy,and 1 case(5.3%) for low suspicion for malignancy. Univariate and multivariate analyses revealed that the degree of malignancy of thyroid nodules was significantly associated with ultrasound image classification[OR=9.23(2.96-28.79),P=0.00],but not with age,gender,nodule number,and nodule size (all P>0.05).Conclusion Ultrasound diagnosis by using the present thyroid ultrasound classification system can be helpful for distinguishing malignant and benign AUS thyroid nodules.


Asunto(s)
Glándula Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/diagnóstico por imagen , Nódulo Tiroideo/diagnóstico por imagen , Biopsia con Aguja Fina , Humanos , Ultrasonografía
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(3): 300-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26149141

RESUMEN

OBJECTIVE: To investigate the role of quantitative three-dimensional (3D) power Doppler ultrasound in differentiating malignant and benign thyroid nodule. METHODS: A total of 92 lesions in 86 patients were preoperatively examined using 3D power Doppler ultrasound. The Virtual Organ Computer-aided Analysis(VOCAL)-imaging program was used to analyze the stored volume ultrasound. The differences in the mean gray value (MG), vascularization index (VI), flow index(FI), and vascularization flow index (VFI) were compared between benign and malignant lesions. RESULTS: The MG of the malignant thyroid nodules was significantly lower than that of the benign ones (28.27±7.21 vs. 32.89±8.73,P=0.007). The benign nodules had significantly higher VI,FI,and VFI than the malignant nodules [VI:(40.43±26.55)% vs. (26.87±23.06)%,P=0.011;FI:41.03±7.19 vs. 37.51±7.17,P=0.022;VFI:18.23±14.60 vs. 11.47±12.47, P=0.009]. Also,76.5% (39/51) of the malignant nodules and 92.7% (38/41) of the benign nodules had higher VIs in the shell of the lesion than that of the whole lesion,and 80.4%(41/51) of the malignant nodules and 95.1% (39/41) of the benign nodules had higher FIs in the shell of the lesion than that of the whole lesion. CONCLUSIONS: Quantitative 3D power Doppler ultrasound provides a useful tool in distinguishing benign and malignant thyroid nodules. The malignant thyroid nodules have lower echoes than the benign nodules, wherese the benign nodules have larger blood flow than the malignant nodules.


Asunto(s)
Imagenología Tridimensional , Enfermedades de la Tiroides , Neoplasias de la Tiroides , Nódulo Tiroideo , Angiografía , Humanos , Neovascularización Patológica , Ultrasonografía Doppler , Procedimientos Quirúrgicos Vasculares
19.
J Cell Mol Med ; 18(4): 735-48, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24467451

RESUMEN

Our research aims to evaluate the function of the STAMP2 gene, an important trigger in insulin resistance (IR), and explore its role in macrophage apoptosis in diabetic atherosclerotic vulnerable plaques. The characteristics of diabetic mice were measured by serial metabolite and pathology tests. The level of STAMP2 was measured by RT-PCR and Western blot. The plaque area, lipid and collagen content of brachiocephalic artery plaques were measured by histopathological analyses, and the macrophage apoptosis was measured by TUNEL. Correlation of STAMP2/Akt signaling pathway and macrophage apoptosis was validated by Ad-STAMP2 transfection and STAMP2 siRNA inhibition. The diabetic mice showed typical features of IR, hyperglycaemia. Overexpression of STAMP2 ameliorated IR and decreased serum glucose level. In brachiocephalic lesions, lipid content, macrophage quantity and the vulnerability index were significantly decreased by overexpression of STAMP2. Moreover, the numbers of apoptotic cells and macrophages in lesions were both significantly decreased. In vitro, both mRNA and protein expressions of STAMP2 were increased under high glucose treatment. P-Akt was highly expressed and caspase-3 was decreased after overexpression of STAMP2. However, expression of p-Akt protein was decreased and caspase-3 was increased when STAMP2 was inhibited by siRNA. STAMP2 overexpression could exert a protective effect on diabetic atherosclerosis by reducing IR and diminishing macrophage apoptosis.


Asunto(s)
Aterosclerosis/genética , Aterosclerosis/terapia , Diabetes Mellitus Tipo 2/genética , Proteínas de la Membrana/genética , Placa Aterosclerótica/genética , Animales , Apoptosis/genética , Aterosclerosis/patología , Diabetes Mellitus Tipo 2/patología , Dieta Alta en Grasa , Regulación de la Expresión Génica , Resistencia a la Insulina/genética , Macrófagos/patología , Proteínas de la Membrana/biosíntesis , Ratones , Proteína Oncogénica v-akt/genética , Placa Aterosclerótica/patología , Placa Aterosclerótica/terapia , Transducción de Señal/genética
20.
Exp Mol Pathol ; 96(1): 80-4, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24368111

RESUMEN

BACKGROUND: Renal fibrosis is thought to be the common pathway in most cases of chronic kidney disease. Recently, TRIB3 was found to play an important role in progression of cardiac fibrosis in an insulin-resistant state. We investigated whether TRIB3 might participate in the pathogenesis of renal fibrosis in insulin-resistant rats. METHODS: We randomly separated 40 male Sprague-Dawley into 4 groups for treatment (n = 10 each): control and high-fat diet (HFD) with TRIB3 siRNA adenovirus transfection, vehicle transfection or HFD alone. Insulin resistance markers were measured. Renal tissues were stained with hematoxylin and eosin, Masson's trichrome and periodic acid-Schiff. RESULTS: Rats with HFD showed insulin resistance and TRIB3 overexpression. Upregulated TRIB3 expression could induce renal fibrosis accompanied by increased phosphorylation of extracellular signal-regulated kinase (ERK). Also, TRIB3 siRNA knockdown could ameliorate renal fibrosis, which was accompanied by decreased phosphorylation of ERK. CONCLUSIONS: TRIB3 gene silencing can attenuate renal fibrosis for beneficial effect on the development of renal fibrosis in chronic kidney disease in rat.


Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Dieta Alta en Grasa/efectos adversos , Fibrosis/etiología , Silenciador del Gen , Resistencia a la Insulina , Enfermedades Renales/etiología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Represoras/antagonistas & inhibidores , Animales , Proteínas de Ciclo Celular/genética , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular , Fibrosis/metabolismo , Fibrosis/patología , Immunoblotting , Técnicas para Inmunoenzimas , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , ARN Interferente Pequeño/genética , Ratas , Ratas Sprague-Dawley , Proteínas Represoras/genética
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