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1.
Physiol Plant ; 176(2): e14230, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38413388

RESUMEN

The grain yield is closely associated with spikelet fertility in rice (Oryza sativa L.) under high temperatures, and nitrogen (N) plays a crucial role in yield formation. To investigate the effect of panicle N application on yield formation under high temperatures at the panicle initiation stage, two rice varieties [Liangyoupeijiu (LYPJ, heat susceptible) and Shanyou63 (SY63, heat tolerant)] were grown and exposed to high daytime temperature (HT) and control temperature (Control) during the panicle initiation stage. Low (LPN) and high (HPN) panicle N applications were conducted. HT markedly decreased the yields by 87% at LPN and 48% at HPN in LYPJ and 31% at LPN and 36% at HPN in SY63. The decrease in grain yield under HT was primarily attributed to the decline in spikelet fertility, HPN increased spikelet fertility. HT resulted in the abnormal development of anthers, which included disordered, enlarged, and broken anther wall layers, degraded and irregularly shaped microspores, delayed tapetum degradation, less vacuolated microspores per locule, abnormal and aborted pollen grains; however, HPN improved the development of anthers under HT, particularly in LYPJ. A high rate of evapotranspiration resulted in an approximately 1°C decrease in panicle temperatures at HPN compared with that at LPN in both varieties under HT. Overall, these results demonstrate that the increased panicle N application favors normal anther development in LYPJ by decreasing the panicle temperature, which results in high pollen viability and spikelet fertility, and consequently less yield loss under HT.


Asunto(s)
Oryza , Temperatura , Nitrógeno/farmacología , Calor , Polen
2.
J Am Chem Soc ; 145(14): 7983-7991, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36974976

RESUMEN

Conjugate addition is among the most important synthetic protocols for constructing carbon skeletons and is widely used to synthesize natural products and drugs. However, asymmetric catalysis studies have mainly focused on constructing stereogenic centers arising from conjugate alkenes. Here, we report the first photoinduced cobalt-catalyzed dynamic kinetic reductive conjugate addition reaction that enables the formation of heterobiaryls with axial chirality (45 examples, up to 91% yield and 97% ee). This method features mild reaction conditions, good functional-group tolerance, and excellent enantiomeric control. Significantly, large amounts of metal waste and precious metal catalysts can be avoided under these conditions. Migration of the chiral arylcobalt species into the alkene might be the rate-determining step based on kinetic studies.

3.
Anal Chem ; 95(24): 9373-9379, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37276048

RESUMEN

Extracellular vesicle PD-L1 (programmed death-1 ligand 1) is of greater value in tumor diagnosis, prognosis, and efficacy monitoring of anti-PD-1/PD-L1 immunotherapy. However, soluble PD-L1 interferes with the accurate detection of extracellular vesicle (EV) PD-L1. Here, we developed a microfluidic differentiation method for the detection of extracellular PD-L1, without the interference of soluble, by DNA computation with lipid probes and PD-L1 aptamer as inputs (DECLA). For the developed DECLA method, a cholesterol-DNA probe was designed that efficiently embeds into the EV membrane, and an aptamer-based PD-L1 probe was used for PD-L1 recognition. Due to the stable secondary structure of the designed connector, only cobinding of cholesterol-DNA and PD-L1 affinity probe induced biotin-labeled connector activation, while soluble PD-L1 cannot hybridize. As a result, PD-L1 EVs can be efficiently captured by streptavidin-functioned herringbone chip and quantified by anti-CD63-induced fluorescence signal. The high specificity of dual-input DNA computation allied to the high sensitivity of microfluidic-based detection was suitable for distinguishing lung cancer patients from healthy donors, highlighting its potential translation to clinical diagnosis and therapy monitoring.


Asunto(s)
Antígeno B7-H1 , Neoplasias Pulmonares , Humanos , Computadores Moleculares , Microfluídica , Neoplasias Pulmonares/patología , Pronóstico
4.
Development ; 147(1)2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31806662

RESUMEN

Although cytokinesis has been intensely studied, the way it is executed during development is not well understood, despite a long-standing appreciation that various aspects of cytokinesis vary across cell and tissue types. To address this, we investigated cytokinesis during the invariant Caenorhabditis elegans embryonic divisions and found several parameters that are altered at different stages in a reproducible manner. During early divisions, furrow ingression asymmetry and midbody inheritance is consistent, suggesting specific regulation of these events. During morphogenesis, we found several unexpected alterations to cytokinesis, including apical midbody migration in polarizing epithelial cells of the gut, pharynx and sensory neurons. Aurora B kinase, which is essential for several aspects of cytokinesis, remains apically localized in each of these tissues after internalization of midbody ring components. Aurora B inactivation disrupts cytokinesis and causes defects in apical structures, even if inactivated post-mitotically. Therefore, we demonstrate that cytokinesis is implemented in a specialized way during epithelial polarization and that Aurora B has a role in the formation of the apical surface.


Asunto(s)
Aurora Quinasa B/fisiología , Proteínas de Caenorhabditis elegans/fisiología , Caenorhabditis elegans/embriología , Caenorhabditis elegans/enzimología , Citocinesis , Morfogénesis , Animales , Caenorhabditis elegans/citología , Polaridad Celular , Citocinesis/fisiología , Dendritas/fisiología , Embrión no Mamífero/citología , Células Epiteliales/fisiología , Intestinos/embriología , Neuronas/citología , Faringe/embriología , Propiedades de Superficie
5.
Molecules ; 28(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38138476

RESUMEN

This study primarily focused on the efficient transformation of low-priced blue coke powder into a high-capacity adsorbent and aimed to address the pollution issue of hexavalent chromium (Cr (VI))-laden wastewater and to facilitate the effective utilization of blue coke powder. A two-step method was utilized to fabricate a blue coke-based nitric acid-modified material (LCN), and the impact of nitric acid modification on the material's structure and its efficacy in treating Cr (VI)-contaminated wastewater was evaluated. Our experimental results illustrated that, under identical conditions, LCN exhibited superior performance for Cr (VI) treatment compared to the method employing only potassium hydroxide (LCK). The specific surface area and pore volume of LCN were 1.39 and 1.36 times greater than those of LCK, respectively. Further chemical composition analysis revealed that the functional group structure on the LCN surface was more conducive to Cr (VI) adsorption. The highest amount of Cr (VI) that LCN could bind was measured at 181.962 mg/g at 318 K. This was mostly due to chemisorption, which is dominated by redox reactions. The Cr (VI) removal process by LCN was identified to be a spontaneous, exothermic, and entropy-increasing process. Several tests on recycling and reuse showed that LCN is a stable and effective chromium-containing wastewater adsorbent, showing that it could be used in many situations.

6.
Int J Environ Health Res ; 33(7): 629-638, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35220835

RESUMEN

Little concern has been paid to the relationship between temperature and varicella among adults. Daily meteorological data and varicella cases in Qingdao among adults from 1 January 2008 to 31 December 2019 were collected. A combination of quasi-Poisson generalized additive model (GAM) and distributed lag non-linear model (DLNM) was conducted to assess the temperature-lag-varicella relationship. We also estimated the lag-response curves for different temperatures and the exposure-response relationships for different lag days. The number of varicella cases was 10,296. Compared with the minimum-varicella temperature (25°C), we found the largest effect of temperature on varicella within 21 lag days was at 1°C (RR, 6.72; 95% CI, 2.90-15.57), and then the effect declined as the temperature increased. A similar trend of rising first and then falling was found in temperature-response curves for different lag days. A reverse U-shape lag pattern was found for different levels of temperatures. Temperature may affect varicella.


Asunto(s)
Varicela , Humanos , Adulto , Temperatura , Varicela/epidemiología , China/epidemiología
7.
Plant Cell Physiol ; 63(10): 1510-1525, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-35946132

RESUMEN

Phloem unloading plays an important role in photoassimilate partitioning and grain yield improvements in cereal crops. The phloem unloading strategy and its effects on photoassimilate translocation and yield formation remain unclear in rice. In this study, plasmodesmata were observed at the interface between the sieve elements (SEs) and companion cells (CCs), and between the SE-CC complex and surrounding parenchyma cells (PCs) in phloem of the dorsal vascular bundle in developing caryopses. Carboxyfluorescein (CF) signal was detected in the phloem of caryopses, which showed that CF was unloaded into caryopses. These results indicated that the SE-CC complex was symplasmically connected with adjacent PCs by plasmodesmata. Gene expression for sucrose transporter (SUT) and cell wall invertase (CWI), and OsSUT1 and OsCIN1 proteins were detected in developing caryopses, indicating that rice plants might actively unload sucrose into caryopses by the apoplasmic pathway. Among three rice recombinant inbred lines, R201 exhibited lower plasmodesmal densities at the boundaries between cell types (SE-CC, SE-PC and CC-PC) in developing caryopses than R91 and R156. R201 also had lower expression of SUT and CWI genes and lower protein levels of OsSUT1 and OsCIN1, as well as CWI activity, than R91 and R156. These data agreed with stem non-structural carbohydrate (NSC) translocation and grain yields for the three lines. The nitrogen application rate had no significant effect on plasmodesmal densities at the interfaces between different cells types, and did not affect CF unloading in the phloem of developing caryopses. Low nitrogen treatment enhanced expression levels of OsSUT and OsCIN genes in the three lines. These results suggested that nitrogen application had no substantial effect on symplasmic unloading but affected apoplasmic unloading. Therefore, we concluded that poor symplasmic and apoplasmic unloading in developing caryopses might result in low stem NSC translocation and poor grain yield formation of R201.


Asunto(s)
Oryza , Floema , Floema/metabolismo , Oryza/genética , Oryza/metabolismo , Grano Comestible/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , beta-Fructofuranosidasa/metabolismo , Sacarosa/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Nitrógeno/metabolismo , Transporte Biológico
8.
J Org Chem ; 87(18): 12460-12469, 2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-36067376

RESUMEN

A high efficiency protocol was developed for the synthesis of 2,5-disubstituted oxazoles via iodine-promoted oxidative domino cyclization. These reactions were performed with readily available methyl azaarenes and α-amino ketones under metal-free conditions. This protocol is a simple method with high functional group compatibility, a wide range of substrates, and excellent yield, providing a new way to synthesize azaarene-attached oxazoles.


Asunto(s)
Yodo , Cetonas , Catálisis , Yoduros , Estructura Molecular , Oxazoles , Estrés Oxidativo
9.
BMC Plant Biol ; 21(1): 428, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34544370

RESUMEN

BACKGROUND: Decreased spikelet fertility is often responsible for reduction in grain yield in rice (Oryza sativa L.). In this study, two varieties with different levels of heat tolerance, Liangyoupeijiu (LYPJ, heat susceptible) and Shanyou63 (SY63, heat tolerant) were subjected to two temperature treatments for 28 days during the panicle initiation stage in temperature/relative humidity-controlled greenhouses: high temperature (HT; 37/27 °C; day/night) and control temperature (CK; 31/27 °C; day/night) to investigate changes in anther development under HT during panicle initiation and their relationship with spikelet fertility. RESULTS: HT significantly decreased the grain yield of LYPJ by decreasing the number of spikelets per panicle and seed setting percentage. In addition, HT produced minor adverse effects in SY63. The decreased spikelet fertility was primarily attributed to decreased pollen viability and anther dehiscence, as well as poor pollen shedding of the anthers of LYPJ under HT. HT resulted in abnormal anther development (fewer vacuolated microspores, un-degraded tapetum, unevenly distributed Ubisch bodies) and malformation of pollen (obscure outline of the pollen exine with a collapsed bacula, disordered tectum, and no nexine of the pollen walls, uneven sporopollenin deposition on the surface of pollen grains) in LYPJ, which may have lowered pollen viability. Additionally, HT produced a compact knitted anther cuticle structure of the epidermis, an un-degraded septum, a thickened anther wall, unevenly distributed Ubisch bodies, and inhibition of the confluent locule, and these malformed structures may be partially responsible for the decreased anther dehiscence rate and reduced pollen shedding of the anthers in LYPJ. In contrast, the anther wall and pollen development of SY63 were not substantially changed under HT. CONCLUSIONS: Our results suggest that disturbed anther walls and pollen development are responsible for the reduced spikelet fertility and grain yield of the tested heat susceptible variety, and noninvasive anthers and pollen formation in response to HT were associated with improved heat tolerance.


Asunto(s)
Fertilidad/genética , Flores/crecimiento & desarrollo , Flores/genética , Calor , Oryza/crecimiento & desarrollo , Oryza/genética , Termotolerancia/genética , China , Productos Agrícolas/genética , Productos Agrícolas/fisiología , Fertilidad/fisiología , Variación Genética , Genotipo , Termotolerancia/fisiología
10.
Indoor Air ; 31(3): 755-768, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33047373

RESUMEN

The intensity, frequency, duration, and contribution of distinct PM2.5 sources in Asian households have seldom been assessed; these are evaluated in this work with concurrent personal, indoor, and outdoor PM2.5 and PM1 monitoring using novel low-cost sensing (LCS) devices, AS-LUNG. GRIMM-comparable observations were acquired by the corrected AS-LUNG readings, with R2 up to 0.998. Twenty-six non-smoking healthy adults were recruited in Taiwan in 2018 for 7-day personal, home indoor, and home outdoor PM monitoring. The results showed 5-min PM2.5 and PM1 exposures of 11.2 ± 10.9 and 10.5 ± 9.8 µg/m3 , respectively. Cooking occurred most frequently; cooking with and without solid fuel contributed to high PM2.5 increments of 76.5 and 183.8 µg/m3 (1 min), respectively. Incense burning had the highest mean PM2.5 indoor/outdoor (1.44 ± 1.44) ratios at home and on average the highest 5-min PM2.5 increments (15.0 µg/m3 ) to indoor levels, among all single sources. Certain events accounted for 14.0%-39.6% of subjects' daily exposures. With the high resolution of AS-LUNG data and detailed time-activity diaries, the impacts of sources and ventilations were assessed in detail.


Asunto(s)
Contaminación del Aire Interior/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente/instrumentación , Material Particulado , Adulto , Contaminantes Atmosféricos , Culinaria , Monitoreo del Ambiente/métodos , Humanos , Tamaño de la Partícula , Estaciones del Año , Taiwán , Ventilación
11.
12.
Sensors (Basel) ; 20(17)2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32899301

RESUMEN

Many low-cost sensors (LCSs) are distributed for air monitoring without any rigorous calibrations. This work applies machine learning with PM2.5 from Taiwan monitoring stations to conduct in-field corrections on a network of 39 PM2.5 LCSs from July 2017 to December 2018. Three candidate models were evaluated: Multiple linear regression (MLR), support vector regression (SVR), and random forest regression (RFR). The model-corrected PM2.5 levels were compared with those of GRIMM-calibrated PM2.5. RFR was superior to MLR and SVR in its correction accuracy and computing efficiency. Compared to SVR, the root mean square errors (RMSEs) of RFR were 35% and 85% lower for the training and validation sets, respectively, and the computational speed was 35 times faster. An RFR with 300 decision trees was chosen as the optimal setting considering both the correction performance and the modeling time. An RFR with a nighttime pattern was established as the optimal correction model, and the RMSEs were 5.9 ± 2.0 µg/m3, reduced from 18.4 ± 6.5 µg/m3 before correction. This is the first work to correct LCSs at locations without monitoring stations, validated using laboratory-calibrated data. Similar models could be established in other countries to greatly enhance the usefulness of their PM2.5 sensor networks.

13.
Sensors (Basel) ; 20(13)2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32629896

RESUMEN

To tackle the challenge of the data accuracy issues of low-cost sensors (LCSs), the objective of this work was to obtain robust correction equations to convert LCS signals into data comparable to that of research-grade instruments using side-by-side comparisons. Limited sets of seed LCS devices, after laboratory evaluations, can be installed strategically in areas of interest without official monitoring stations to enable reading adjustments of other uncalibrated LCS devices to enhance the data quality of sensor networks. The robustness of these equations for LCS devices (AS-LUNG with PMS3003 sensor) under a hood and a chamber with two different burnt materials and before and after 1.5 years of field campaigns were evaluated. Correction equations with incense or mosquito coils burning inside a chamber with segmented regressions had a high R2 of 0.999, less than 6.0% variability in the slopes, and a mean RMSE of 1.18 µg/m3 for 0.1-200 µg/m3 of PM2.5, with a slightly higher RMSE for 0.1-400 µg/m3 compared to EDM-180. Similar results were obtained for PM1, with an upper limit of 200 µg/m3. Sensor signals drifted 19-24% after 1.5 years in the field. Practical recommendations are given to obtain equations for Federal-Equivalent-Method-comparable measurements considering variability and cost.

14.
Sensors (Basel) ; 20(17)2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32825023

RESUMEN

Traffic emission is one of the major contributors to urban PM2.5, an important environmental health hazard. Estimating roadside PM2.5 concentration increments (above background levels) due to vehicles would assist in understanding pedestrians' actual exposures. This work combines PM2.5 sensing and vehicle detecting to acquire roadside PM2.5 concentration increments due to vehicles. An automatic traffic analysis system (YOLOv3-tiny-3l) was applied to simultaneously detect and track vehicles with deep learning and traditional optical flow techniques, respectively, from governmental cameras that have low resolutions of only 352 × 240 pixels. Evaluation with 20% of the 2439 manually labeled images from 23 cameras showed that this system has 87% and 84% of the precision and recall rates, respectively, for five types of vehicles, namely, sedan, motorcycle, bus, truck, and trailer. By fusing the research-grade observations from PM2.5 sensors installed at two roadside locations with vehicle counts from the nearby governmental cameras analyzed by YOLOv3-tiny-3l, roadside PM2.5 concentration increments due to on-road sedans were estimated to be 0.0027-0.0050 µg/m3. This practical and low-cost method can be further applied in other countries to assess the impacts of vehicles on roadside PM2.5 concentrations.

15.
Ecotoxicol Environ Saf ; 184: 109579, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31505405

RESUMEN

DNA methylation have been suggested as possible mediators of long-term health effects of environmental stressors. This study aimed to evaluate the potential therapy of methylation of S-adenosyl-l-methionine (SAM) on PFOS induced trangeneral reproductive toxicity. In this study, postnatal 5d Sprague Dawley rats were randomly divided into four groups: control, PFOS, PFOS + SAM, and PFOS + Decitabine (DAC). The F0 rats were exposed to 5 mg/kg PFOS and SAM or DAC until PND60. The development of the offsprings were monitored without PFOS exposure. The fertility in F0, F1 rats, and change in F1 testes were observed. The results were as follows. The significant increase in F0 pregnancy rate, and survival rate in F1 offspring in PFOS + SAM relative to PFOS group were observed. Changes of birth weights and physical development in F1 offspring with SAM were approached as a corresponding variation of the control after the deparation period. No pregnant in F1 maternal rats in the PFOS and DAC groups were found, but pregnant in the SAM group. Significantly decrease in the percentage of abnormal seminiferous tubules and increase in expression of promyelocytic leukemia zinc finger (PLZF+) spermatogonial stem cells in F1 testis compared with the PFOS group. Taken together, Methyl donor SAM improve PLZF + spermatogonia stem cell proliferation, attenuate damage in testicular tissue structure, which subsequently improve the transgenerational growth retard and infertility induced by PFOS chronic stress.


Asunto(s)
Ácidos Alcanesulfónicos/toxicidad , Fluorocarburos/toxicidad , Efectos Tardíos de la Exposición Prenatal/prevención & control , Reproducción/efectos de los fármacos , S-Adenosilmetionina/uso terapéutico , Animales , Peso al Nacer , Decitabina/uso terapéutico , Femenino , Masculino , Embarazo , Índice de Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/mortalidad , Efectos Tardíos de la Exposición Prenatal/patología , Ratas Sprague-Dawley , Espermatogonias/citología , Espermatogonias/efectos de los fármacos , Tasa de Supervivencia , Testículo/citología , Testículo/efectos de los fármacos
16.
Mikrochim Acta ; 186(12): 827, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31754798

RESUMEN

A core-shell structured magnetic covalent organic frameworks of the type Fe3O4@COFs was prepared by using the Fe3O4 nanoparticles as magnetic core, and 4,4"-diamino-p-terphenyl and 1,3,5-tris(p-formylphenyl)benzene as two building blocks. The Fe3O4@COFs were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive spectrum, Fourier transform infrared spectroscopy, zeta potentiometric analysis, X-ray diffraction, vibrating sample magnetometry, thermogravimetric analysis and the nitrogen adsorption-desorption isotherms. The Fe3O4@COFs have core-shell structure with average diameter of 200 ± 2.4 nm, a high specific surface area (124 m2·g-1), uniform pore size distribution (3.1 nm), good magnetic responsivity (36.8 emu·g-1), good thermal and chemical stability. They were applied as the sorbents for magnetic solid phase extraction (MSPE) for fluoroquinolones (FQs) ciprofloxacin, enrofloxacin, lomefloxacin, gatifloxacin, levofloxacin and pefloxacin. The effects of sorbent dosage, extraction time, p H value, ionic strength, desorption solvent and desorption time were investigated. By combining MSPE with HPLC-DAD analysis, a rapid and sensitive method was developed for the enrichment and determination of these FQs. The method had good linearity in the range of 2.5-1500 ng·g-1 FQ concentration range and low limits of detection (0.25-0.5 ng·g-1). The method was successfully applied to the extraction and determination of FQs in (spiked) pork, milk and human plasma samples. Recoveries ranged from 78.7-103.5% (with RSD<6.2%). Graphical abstract Schematic representation of the magnetic covalent organic frameworks which prepared by using the Fe3O4 nanoparticles as magnetic core, 4,4"-diamino-p-terphenyl and 1,3,5-tris(p-formylphenyl)benzene as two building blocks. The Fe3O4@COFs were applied as adsorbents for magnetic solid phase extraction of six fluoroquinolones (FQs) and HPLC-DAD was applied to analysis the extraction efficiencies.

17.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31861919

RESUMEN

Akkermansia muciniphila can produce various mucin-degrading proteins. However, the functional characteristics of these proteins and their role in mucin degradation are unclear. Of the predicted protein-coding genes, Amuc_1434, which encodes for a hypothetical protein, is the focus in this study. A recombinant enzyme Amuc_1434 containing the 6× His-tag produced in Escherichia coli (hereinafter termed Amuc_1434*) was isolated to homogeneity and biochemically characterised. Results showed that the enzyme can hydrolyse hemoglobin with an activity of 17.21 U/µg. The optimal pH and temperature for hemoglobin hydrolysis of Amuc_1434* were found to be around 8.0 and 40 °C, respectively. Amuc_1434* is identified as a member of the aspartic protease family through the action of inhibitor pepstatin A. Amuc_1434* promotes the adhesion of colon cancer cell line LS174T, which can highly express Muc2. Significantly Amuc_1434* can degrade Muc2 of colon cancer cells. Amuc_1434 is mainly located in the colon of BALB/c mice. These results suggest that the presence of Amuc_1434 from Akkermansia muciniphila may be correlated with the restoration of gut barrier function by decreasing mucus layer thickness.


Asunto(s)
Proteasas de Ácido Aspártico/metabolismo , Proteínas Bacterianas/metabolismo , Mucina 2/metabolismo , Verrucomicrobia/metabolismo , Akkermansia , Animales , Proteasas de Ácido Aspártico/aislamiento & purificación , Línea Celular Tumoral , Células HeLa , Humanos , Ratones Endogámicos BALB C , Proteolisis
18.
Physiol Plant ; 163(1): 45-58, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29055043

RESUMEN

Salinity significantly limits leaf photosynthesis but the factors causing the limitation in salt-stressed leaves remain unclear. In the present work, photosynthetic and biochemical traits were investigated in four rice genotypes under two NaCl concentration (0 and 150 mM) to assess the stomatal, mesophyll and biochemical contributions to reduced photosynthetic rate (A) in salt-stressed leaves. Our results indicated that salinity led to a decrease in A, leaf osmotic potential, electron transport rate and CO2 concentrations in the chloroplasts (Cc ) of rice leaves. Decreased A in salt-stressed leaves was mainly attributable to low Cc , which was determined by stomatal and mesophyll conductance. The increased stomatal limitation was mainly related to the low leaf osmotic potential caused by soil salinity. However, the increased mesophyll limitation in salt-stressed leaves was related to both osmotic stress and ion stress. These findings highlight the importance of considering mesophyll conductance when developing salinity-tolerant rice cultivars.


Asunto(s)
Dióxido de Carbono/metabolismo , Oryza/fisiología , Fotosíntesis/fisiología , Cloroplastos/fisiología , Difusión , Células del Mesófilo/fisiología , Ósmosis , Hojas de la Planta/fisiología , Estomas de Plantas/fisiología , Salinidad , Cloruro de Sodio/metabolismo , Suelo/química , Estrés Fisiológico
19.
Int J Mol Sci ; 18(6)2017 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-28594376

RESUMEN

Perfluorooctanoic acid (PFOA) is an environmental contaminant that could induce developmental cardiotoxicity in a chicken embryo, which may be alleviated by l-carnitine. To explore the roles of reactive oxygen species (ROS) and nitric oxide (NO) in such changes and the potential effects of l-carnitine, fertile chicken eggs were exposed to PFOA via an air cell injection, with or without l-carnitine co-treatment. The ROS and NO levels in chicken embryo hearts were determined with electron spin resonance (ESR), and the protein levels of the nuclear factor κ-light chain-enhancer of activated B cells (NF-κB) p65 and inducible nitric oxide synthase (iNOS) in chicken embryo hearts were assessed with western blotting. The results of ESR indicated that PFOA exposure induced an elevation in the ROS levels in ED19 chicken embryo hearts and hatchling chicken hearts, while l-carnitine could alleviate such changes. Meanwhile, increased NO levels were observed in ED19 embryo hearts and hatchling hearts following PFOA exposure, while l-carnitine co-treatment exerted modulatory effects. Western blotting revealed that p65 translocation in ED19 embryo hearts and hatchling hearts was enhanced by PFOA, while l-carnitine co-treatment alleviated such changes. iNOS expression levels in ED19 embryo hearts followed the same pattern as NO levels, while a suppression of expression was observed in hatchling hearts exposed to PFOA. ROS/NF-κB p65 and iNOS/NO seem to be involved in the late stage (ED19 and post hatch) of PFOA-induced developmental cardiotoxicity in a chicken embryo. l-carnitine could exert anti-oxidant and NO modulatory effects in the developing chicken embryo hearts, which likely contribute to its cardioprotective effects.


Asunto(s)
Caprilatos/efectos adversos , Cardiotónicos/farmacología , Cardiotoxicidad/etiología , Cardiotoxicidad/metabolismo , Carnitina/farmacología , Fluorocarburos/efectos adversos , Óxido Nítrico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Cardiotoxicidad/prevención & control , Embrión de Pollo , Corazón/efectos de los fármacos , Frecuencia Cardíaca , Óxido Nítrico Sintasa de Tipo II/metabolismo , Factor de Transcripción ReIA/metabolismo
20.
Mol Cell Biochem ; 420(1-2): 171-84, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27514536

RESUMEN

The purpose of this study was to investigate the antiatherosclerosis effects of ursolic acid (UA) in high-fat diet-fed quails (Coturnix coturnix) and potential mechanism. Quails were treated with high-fat diet (14 % pork oil, 1 % cholesterol w/w) with or without UA (50, 150, or 300 mg/kg/day) for 10 weeks. Serum lipid profile was assessed at 0, 4.5, and 10 weeks. After 10 weeks, serum antioxidant status and morphology of aorta were assessed. Additionally, human umbilical vein endothelial cells (HUVECs) were exposed to 100 µg/ml oxidized low-density lipoprotein (ox-LDL) for 24 h, with or without pretreatment with UA (5, 10 or 20 µM) for 16 h, autophagy inhibitor 3-MA 5 mM for 2 h, or SIRT1 inhibitor EX-527 10 µM for 2 h. Cell viability and oxidative stress status were assessed and autophagy status was determined. Acetylation of lysine residue on Atg5 was assessed with immunoprecipitation. In results, high-fat diet negatively affected serum lipid profile and antioxidant status in quails and induced significant histological changes. Cotreatment with UA remarkably alleviated such changes. In HUVECs, ox-LDL treatment induced significant cytotoxicity along with oxidative stress, while UA cotreatment alleviated such changes significantly. UA treatment induced autophagy, enhanced SIRT1 expression, and decreased acetylation of lysine residue on Atg5. Cotreatment with 3-MA or EX-527 effectively abolished UA's protective effects. In summary, UA exerted antiatherosclerosis effects in quails and protected HUVECs from ox-LDL induced cytotoxicity, and the mechanism is associated with increased SIRT1 expression, decreased Atg5 acetylation on lysine residue, and increased autophagy.


Asunto(s)
Aterosclerosis , Proteína 5 Relacionada con la Autofagia/biosíntesis , Autofagia/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Sirtuina 1/biosíntesis , Triterpenos/farmacología , Acetilación/efectos de los fármacos , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Aterosclerosis/patología , Humanos , Lipoproteínas LDL/toxicidad , Masculino , Codorniz/metabolismo , Ácido Ursólico
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