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1.
BMC Genomics ; 25(1): 597, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877411

RESUMEN

Chrozophora sabulosa Kar. & Kir. is a biennial herbaceous plant that belongs to the Euphorbiaceae family and has medicinal properties. This research aimed to identify the genetic characteristics and phylogenetic position of the Chrozophora genus within the Euphorbiaceae family. The evolutionary position of the Chrozophora genus was previously unknown due to insufficient research. Therefore, to determine the evolutionary link between C. sabulosa and other related species, we conducted a study using the NGS Illumina platform to sequence the C. sabulosa chloroplast (cp.) genome. The study results showed that the genome was 156,488 bp in length. It had a quadripartite structure consisting of two inverted repeats (IRb and IRa) of 24,649-bp, separated by an 87,696-bp LSC region and a 19,494-bp SSC region. The CP genome contained 113 unique genes, including four rRNA genes, 30 tRNA genes, and 79 CDS genes. In the second copy of the inverted repeat, there were 18 duplicated genes. The C. sabulosa lacks the petD, petB, rpl2, and rps16 intron. The analysis of simple sequence repeats (SSRs) revealed 93 SSR loci of 22 types and 78 oligonucleotide repeats of four kinds. The phylogenetic investigation showed that the Chrozophora genus evolved paraphyletically from other members of the Euphorbiaceae family. To support the phylogenetic findings, we selected species from the Euphorbiaceae and Phyllanthaceae families to compare with C. sabulosa for Ks and Ka substitution rates, InDels investigation, IR contraction and expansion, and SNPs analysis. The results of these comparative studies align with the phylogenetic findings. We identified six highly polymorphic regions shared by both families, which could be used as molecular identifiers for the Chrozophora genus (rpl33-rps18, rps18-rpl20, rps15-ycf1, ndhG-ndhI, psaI-ycf4, petA-psbJ). The cp. genome sequence of C. sabulosa reveals the evolution of plastid sequences in Chrozophora species. This is the first time the cp. genome of a Chrozophora genus has been sequenced, serving as a foundation for future sequencing of other species within the Chrozophoreae tribe and facilitating in-depth taxonomic research. The results of this research will also aid in identifying new Chrozophora species.


Asunto(s)
Evolución Molecular , Genoma del Cloroplasto , Filogenia
2.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1176-1185, 2023 Mar.
Artículo en Zh | MEDLINE | ID: mdl-37005801

RESUMEN

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.


Asunto(s)
Benzofuranos , Células Endoteliales , Estrés Oxidativo , Benzofuranos/farmacología , Lípidos
3.
Environ Sci Technol ; 56(1): 433-439, 2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34913675

RESUMEN

Exposure to fine particulate matter (PM2.5) is proven to be associated with a decline in renal function. However, few studies have explored the acute renal damage from carbonaceous compounds and water-soluble inorganic ions (WSIIs), which constitute the bulk of total PM2.5 mass. We examined the acute effect of these constituents of ambient PM2.5 on renal function in older Chinese individuals. Seventy-one healthy people aged 60-69 years from Jinan, China, were enrolled and visited monthly and asked to complete survey questionnaires, undergo physical exams, and provide blood samples. The hourly concentrations of organic carbon, elemental carbon (EC), and WSIIs in ambient PM2.5 were collected from a fixed-site monitoring station. The association between PM2.5 constituents and estimated glomerular filtration rate (eGFR) was evaluated using linear mixed-effects models after controlling for a series of covariates. We observed that ambient carbonaceous compounds and WSIIs were associated with a significant decline in renal function. The interquartile range increased in the 24 h moving average of carbonaceous compounds, and WSIIs in ambient PM2.5 were associated with -13.11% [95% confidence interval (95% CI): -19.49, -6.21%] to -0.81% (95% CI: -4.17, 2.67%) changes in eGFR. We found significant associations between EC, chlorine (Cl-), sodium (Na+), and magnesium (Mg2+) and eGFR in single-pollutant, constituent-PM2.5, and residual-constituent models with a lag period of 0-24 h. This study demonstrated that carbonaceous compounds and WSIIs in PM2.5 were inversely associated with renal function.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Anciano , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Humanos , Iones , Riñón/fisiología , Persona de Mediana Edad , Material Particulado/análisis , Agua
4.
Environ Sci Technol ; 56(18): 13160-13168, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36043295

RESUMEN

Dyslipidemia may be a potential mechanism linking fine particulate matter (PM2.5) to adverse cardiovascular outcomes. However, inconsistent associations between PM2.5 and blood lipids have resulted from the existing research, and the joint effect of PM2.5 elemental constituents on blood lipid profiles remains unclear. We aimed to explore the overall associations between PM2.5 elemental constituents and blood lipid profiles and to identify the significant PM2.5 elemental constituents in this association. Sixty-nine elderly people were recruited between September 2018 and January 2019. Each participant completed a survey questionnaire, 3 days of individual exposure monitoring, health examination, and biological sample collection at each follow-up visit. Bayesian kernel machine regression (BKMR) models were used to identify the joint effects of the 17 elemental constituents on blood lipid profiles. Total cholesterol, low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) levels were significantly increased in older adults when exposed to the mixture of PM2.5 elemental constituents. Copper and titanium had higher posterior inclusion probabilities than other constituents, ranging from 0.76 to 0.90 (Cu) and 0.74 to 0.94 (Ti). Copper and titanium in the PM2.5 elemental constituent mixture played an essential role in changes to blood lipid levels. This study highlights the importance of identifying critical hazardous PM2.5 constituents that may cause adverse cardiovascular outcomes in the future.


Asunto(s)
Contaminantes Atmosféricos , Exposición a Riesgos Ambientales , Lípidos , Anciano , Contaminantes Atmosféricos/análisis , Teorema de Bayes , China , LDL-Colesterol , Cobre , Exposición a Riesgos Ambientales/análisis , Humanos , Lípidos/sangre , Persona de Mediana Edad , Material Particulado/análisis , Titanio
5.
Ecotoxicol Environ Saf ; 242: 113934, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35999757

RESUMEN

In aquatic systems, sediment is both a sink for persistent organic pollutants (POPs) and a potential source of POPs release. Consequently, it is important to understand the pollution characteristics and sources of polychlorinated naphthalenes (PCNs) as POPs of Stockholm Convention in sediment for control of the ecological risk. Atmospheric deposition is a potential source of PCNs in sediment. However, there is no clear report on the contribution of atmospheric deposition to PCNs in sediments. In this study, the Chaobai River in China was selected because it is an important drinking water source that is not affected by wastewater discharge. Surface sediments from the river were analyzed for 75 PCN congeners by using high resolution gas chromatography combined with high resolution mass spectrometry. The total PCNs concentration ranged from 54 to 2266 (mean: 402) pg/g. The toxic equivalent quantity of 19 PCNs in surface sediments was 9.69 × 10-2, and CN73, CN66/CN67, and CN63 had the largest contributions to this value. Dichlorinated and trichlorinated naphthalenes were the dominant homologs. The PCN data from the sediment samples in this study were combined with data for PCNs in ambient air from a literature, which has a good match with this study in both temporal and spatial scales. The contribution of atmospheric deposition to PCNs in the surface sediment was evaluated by comparing congener characteristics and correlation analysis. Our study indicated atmospheric transportation and deposition are important pathways for transport of PCNs into surface sediments.


Asunto(s)
Naftalenos , Ríos , China , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Naftalenos/análisis , Ríos/química
6.
J Environ Manage ; 316: 115208, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35550957

RESUMEN

A modified sodium bentonite geosynthetic clay liner (GCL) designed for acid-and-alkaline resistance was evaluated for its potential application in the containment of bauxite residue leachate. A modified fluid loss test was employed to quickly evaluate the hydraulic conductivity (k) of the GCL using distilled water, tap water, and four bauxite liquors (BLs, leachate from bauxite residue reservoirs). The effects of swelling capacity of bentonite, prehydration, hydraulic gradient (i), ionic strength (I), and relative abundance of monovalent and multivalent cations (RMD) on the hydraulic conductivity of the GCL were analyzed. The results indicated that the BLs significantly decreased free swell index of the bentonite. As compared to increasing i, prehydration obviously enhanced hydraulic performance of the GCL. The four BLs increased k of the GCL by a factor of 4-12 relative to the tap water permeation condition, and the resultant k exceeded upper limit of 5.0 × 10-11 m/s for GCLs. The increase in k was attributed to compression in diffuse double layer of the bentonite and dissolution in clay minerals in ion-rich and hyperalkaline BLs, manifesting that further modification on the GCL is needed. The I was found a better indicator than the RMD on correlation with chemical compatibility of the GCL.


Asunto(s)
Bentonita , Eliminación de Residuos , Óxido de Aluminio , Silicatos de Aluminio , Arcilla , Eliminación de Residuos/métodos , Agua
7.
Neural Plast ; 2021: 9912686, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34194489

RESUMEN

Microglia-mediated neuroinflammation is one of the most remarkable hallmarks of neurodegenerative diseases (NDDs), including AD, PD, and ALS. Accumulating evidence indicates that microglia play both neuroprotective and detrimental roles in the onset and progression of NDDs. Yet, the specific mechanisms of action surrounding microglia are not clear. Modulation of microglia function and phenotypes appears to be a potential strategy to reverse NDDs. Until recently, research into the epigenetic mechanisms of diseases has been gradually developed, making it possible to elucidate the molecular mechanisms underlying the epigenetic regulation of microglia in NDDs. This review highlights the function and phenotypes of microglia, elucidates the relationship between microglia, epigenetic modifications, and NDDs, as well as the possible mechanisms underlying the epigenetic modulation of microglia in NDDs with a focus on potential intervention strategies.


Asunto(s)
Epigénesis Genética , Microglía/fisiología , Enfermedades Neurodegenerativas/genética , Metilación de ADN , Código de Histonas , Humanos , Enfermedades Neuroinflamatorias/genética , Enfermedades Neuroinflamatorias/patología , Fenotipo
8.
Opt Express ; 28(3): 3482-3494, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32122015

RESUMEN

Considering the importance of the laser wavelength response and the difficulty in its real-scenario measurement in WMS, a high-accuracy and universal method was developed to characterize the relative wavelength response (RWR) by analyzing the laser current response. A coupling term that depends on both the current scan and the modulation characteristic was introduced to describe the coupling effect between the wavelength scan and modulation. The accuracy of the proposed method was verified with different laser working conditions and scan waveforms. All fitting residuals of the RWR result from the proposed method are smaller than 0.1% of the total scan range and the fitting residual of the ramp scanned WMS is twice smaller than the minimum value from literature. The better calibration-free 2f/1f fitting and more accurate CO2 concentration results also suggest the high accuracy and superiority of the proposed method. Finally, based on the precise prediction of RWR with small scan and modulation indices, the spectral parameters, including line strength and self-collisional broadening coefficient, of CO2 transition at 6976.2026 cm-1 were successfully measured using WMS.

9.
Environ Sci Technol ; 54(20): 13167-13174, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32929958

RESUMEN

Long-term exposure to fine particulate matter (PM2.5) is associated with kidney dysfunction. However, few studies have investigated acute effects of PM2.5 elemental constituents on renal function. We evaluated associations between personal PM2.5 and its elemental constituents and kidney function, assessed by an estimated glomerular filtration rate (eGFR) in Biomarkers of Air Pollutants Exposure in the Chinese aged 60-69 study. Seventy one older individuals were visited monthly between September 2018 and January 2019. Each participant wore a PM2.5 monitor for 72 h, responded to a questionnaire, and underwent a physical examination with blood sampling. Linear mixed-effect models were used to estimate associations between personal PM2.5 elemental constituents and eGFR. We found that significant changes in eGFR from -1.69% [95% confidence interval (CI): -3.34%, -0.01%] to -3.27% (95% CI: -5.04%, -1.47%) were associated with interquartile range (IQR) increases in individual PM2.5 exposures at various lag periods (7-12, 13-24, 0-24, 25-48, and 49-72 h). An IQR increase in 72 h moving averages of copper, manganese, and titanium in personal PM2.5 corresponded to -2.34% (95% CI: -3.67%, -0.99%) to -4.56% (95% CI: -7.04%, -2.00%) changes in eGFR. Personal PM2.5 and some of its elemental constituents are inversely associated with eGFR in older individuals.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Anciano , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , China , Exposición a Riesgos Ambientales/análisis , Humanos , Riñón , Persona de Mediana Edad , Material Particulado/efectos adversos , Material Particulado/análisis
10.
Sensors (Basel) ; 20(3)2020 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-31991920

RESUMEN

The absorbance is of great importance in the tunable diode laser absorption spectroscopy (TDLAS) as it contains information of both gas properties and spectroscopic parameters. A novel, calibration-free wavelength modulation-direct absorption spectroscopy (WM-DAS) is proposed and experimentally verified in this two-part paper. This method combines the capability of absorbance measurement from DAS and the advantages of enhanced noise rejection and high sensitivity from WMS. In this Part I, we focus on the full theoretical basis and procedures of this method from the following three aspects: the high-accuracy characterizations of laser frequency and intensity, noise rejection ability by extracting the characteristic spectra through the fast Fourier transform (FFT) of the light intensity, and the simultaneous fitting strategy for both baseline and absorbance. The preliminary validation experiment of CO transition at 4300.6999 cm-1 in a static gas cell shows the high accuracy of the proposed method.

11.
Sensors (Basel) ; 20(3)2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31979159

RESUMEN

Following the theoretical work in Part I, in this experimental study, the robustness, temporal resolution, and the narrow scan performance of the proposed wavelength modulation-direct absorption spectroscopy (WM-DAS) method are experimentally validated in a high-temperature tube furnace. The electromagnetic and other random-frequency noises can be effectively eliminated by extracting the characteristic spectra of the light intensity. The performance of WM-DAS with modulation frequencies from 0.1 to 100 kHz and scan indexes from 3.3 to 11.1 are also investigated at atmospheric pressure. The proposed method produces accurate line profile and high SNR over 500 consistently even with a weak absorption. As for real applications, the spectral line parameters of CO at 4300.6999 cm-1 including the collisional broadening, Dicke narrowing, and their dependence on temperature are measured. Furthermore, the high-speed measurement (1 ms) of the temperature and CO concentration of a McKenna flat flame are demonstrated.

12.
Sensors (Basel) ; 20(3)2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31973109

RESUMEN

A wide-range, calibration-free tunable diode laser spectrometer is established by combining wavelength modulation and direct absorption spectroscopy (WM-DAS) with continuous wave cavity ringdown spectroscopy (CW-CRDS). This spectrometer combines the benefits of absolute concentration measurements, wide range, and high speed, using WM-DAS with enhanced noise reduction in CW-CRDS. The accurate baseline ringdown time, τ0, is calculated by the absorption peak (measured by WM-DAS) and the ringdown time containing gas absorption information (measured by CW-CRDS at the center wavelength of the spectral line). The gas concentration is obtained without measuring τ0 in real time, thus, greatly improving the measuring speed. A WM-DAS/CW-CRDS spectrometer at 1.57 µm for CO detection was assembled for experimental validation of the multiplexing scheme over a concentration ranging from 4 ppm to 1.09% (0.1 MPa, 298 K). The measured concentration of CO at 6374.406 cm-1 shows that the dynamic range of this tunable diode laser absorption spectrometer is extendable up to five orders of magnitude and the corresponding precision is improved. The measurement speed of this spectrometer can extend up to 10 ms, and the detection limit can reach 35 ppb within 25 s.

13.
Int J Neuropsychopharmacol ; 22(1): 57-70, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30407508

RESUMEN

Background: Hyperhomocysteinemia is an independent risk factor for dementia, including Alzheimer's disease. Lowering homocysteine levels with folic acid treatment with or without vitamin B12 has shown few clinical benefits on cognition. Methods: To verify the effect of emodin, a naturally active compound from Rheum officinale, on hyperhomocysteinemia-induced dementia, rats were treated with homocysteine injection (HCY, 400 µg/kg/d, 2 weeks) via vena caudalis. Afterwards, HCY rats with cognitive deficits were administered intragastric emodin at different concentrations for 2 weeks: 0 (HCY-E0), 20 (HCY-E20), 40 (HCY-E40), and 80 mg/kg/d (HCY-E80). Results: ß-Amyloid overproduction, tau hyperphosphorylation, and losses of neuron and synaptic proteins were detected in the hippocampi of HCY-E0 rats with cognitive deficits. HCY-E40 and HCY-E80 rats had better behavioral performance. Although it did not reduce the plasma homocysteine level, emodin (especially 80 mg/kg/d) reduced the levels of ß-amyloid and tau phosphorylation, decreased the levels of ß-site amyloid precursor protein-cleaving enzyme 1, and improved the activity of protein phosphatase 2A. In the hippocampi of HCY-E40 and HCY-E80 rats, the neuron numbers, levels of synaptic proteins, and phosphorylation of the cAMP responsive element-binding protein at Ser133 were increased. In addition, depressed microglial activation and reduced levels of 5-lipoxygenase, interleukin-6, and tumor necrosis factor α were also observed. Lastly, hyperhomocysteinemia-induced microangiopathic alterations, oxidative stress, and elevated DNA methyltransferases 1 and 3ß were rescued by emodin. Conclusions: Emodin represents a novel potential candidate agent for hyperhomocysteinemia-induced dementia and Alzheimer's disease-like features.


Asunto(s)
Demencia/tratamiento farmacológico , Demencia/etiología , Emodina/farmacología , Hiperhomocisteinemia/complicaciones , Hiperhomocisteinemia/tratamiento farmacológico , Nootrópicos/farmacología , Péptidos beta-Amiloides/metabolismo , Animales , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/metabolismo , Trastornos del Conocimiento/patología , Metilación de ADN/efectos de los fármacos , Metilación de ADN/fisiología , Demencia/metabolismo , Demencia/patología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipocampo/patología , Hiperhomocisteinemia/metabolismo , Hiperhomocisteinemia/patología , Masculino , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/patología , Microvasos/efectos de los fármacos , Microvasos/metabolismo , Microvasos/patología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Distribución Aleatoria , Ratas Sprague-Dawley , Proteínas tau/metabolismo
14.
Ecotoxicol Environ Saf ; 171: 518-522, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-30641312

RESUMEN

Portable monitors such as MicroPEM can accurately characterize personal exposure of pollutants, which is critical for linking exposure and health effects of air pollution. The RTI (RTI International, Research Triangle Park, NC, USA) MicroPEM V3.2A provides both real-time fine particulate matter (PM2.5) concentrations and time-integrated PM samples collected onto Teflon filters that can be used to correct real-time data as well as allow further lab chemical analysis of species on filters (e.g., metal, black carbon). Due to the optical reflectivity of local PM sources can be very different from available standard reference particles used for calibration by RTI, there is a need for gravimetric correction and validation at each study location. However, assessments of MicroPEM have been limited in locations with severe air pollution, such as Beijing. We selected a variety of weather and air quality conditions, including both clear and hazy days in Beijing, to compare PM2.5 data among MicroPEMs as well as between MicroPEM and other types of samplers. We also compared MicroPEM real-time PM2.5 concentrations with data from nearby fixed-sites. The results show MicroPEM performed well across a wide range of PM2.5 concentrations (6-461 µg/m3) and MicroPEM data, after gravimetric correction, were consistent with those from moderate-volume samplers. Good agreement was also found between real-time data from MicroPEM and fixed-site data. The present study covered a wide range of pollution levels in actual environments and validated the usage of MicroPEM as a PM2.5 monitor in locations with elevated PM2.5 levels.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Contaminación del Aire/análisis , Beijing , Ciudades , Monitoreo del Ambiente , Humanos , Reproducibilidad de los Resultados
15.
Neural Plast ; 2019: 6856327, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31093272

RESUMEN

Tau hyperphosphorylation is a typical pathological change in Alzheimer's disease (AD) and is involved in the early onset and progression of AD. Epigenetic modification refers to heritable alterations in gene expression that are not caused by direct changes in the DNA sequence of the gene. Epigenetic modifications, such as noncoding RNA regulation, DNA methylation, and histone modification, can directly or indirectly affect the regulation of tau phosphorylation, thereby participating in AD development and progression. This review summarizes the current research progress on the mechanisms of epigenetic modification associated with tau phosphorylation.


Asunto(s)
Enfermedad de Alzheimer/genética , Epigénesis Genética , Neuronas/metabolismo , Proteínas tau/genética , Animales , Metilación de ADN , Código de Histonas , Humanos , Fosforilación , ARN no Traducido/genética , Transducción de Señal
16.
Hum Mol Genet ; 25(3): 448-58, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26612203

RESUMEN

Epilepsy or seizure disorder is among the least understood chronic medical conditions affecting over 65 million people worldwide. Here, we show that disruption of the polycystic kidney disease 2-like 1 (Pkd2l1 or Pkdl), encoding polycystin-L (PCL), a non-selective cation channel, increases neuronal excitability and the susceptibility to pentylenetetrazol-induced seizure in mice. PCL interacts with ß2-adrenergic receptor (ß2AR) and co-localizes with ß2AR on the primary cilia of neurons in the brain. Pkdl deficiency leads to the loss of ß2AR on neuronal cilia, which is accompanied with a remarkable reduction in cAMP levels in the central nervous system (CNS). The reduction of cAMP levels is associated with a reduction in the activation of cAMP response element-binding protein, but not the activation of Ca(2+)/calmodulin-dependent protein kinase II, Akt or mitogen-activated protein kinases. Our data, thus, indicate for the first time that a ciliary protein complex is required for the control of neuronal excitability in the CNS.


Asunto(s)
Canales de Calcio/genética , Corteza Cerebral/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Epilepsia/genética , Hipocampo/metabolismo , Receptores Adrenérgicos beta 2/genética , Receptores de Superficie Celular/genética , Tálamo/metabolismo , Animales , Canales de Calcio/deficiencia , Corteza Cerebral/patología , Cilios/metabolismo , Cilios/patología , AMP Cíclico/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Epilepsia/inducido químicamente , Epilepsia/metabolismo , Epilepsia/patología , Potenciales Postsinápticos Excitadores , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Hipocampo/patología , Humanos , Transporte Iónico , Ratones , Neuronas/metabolismo , Neuronas/patología , Pentilenotetrazol , Receptores Adrenérgicos beta 2/metabolismo , Receptores de Superficie Celular/deficiencia , Transducción de Señal , Tálamo/patología
17.
Opt Express ; 26(22): 29550-29560, 2018 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-30470117

RESUMEN

A novel method with high accuracy and easy implementation was proposed based on the sinewave-scanned direct absorption spectroscopy (DAS) in this paper. A fitting routine in the time domain was developed to simultaneously deduce the baseline and more importantly, absorbance through the explicit baseline expression offered by the sinewave scan. This method effectively solves the difficulties of baseline determination and provides more accurate wavelength calibration compared with conventional DAS. The accuracy and performance with narrow scans and high frequency were experimentally verified using CO transition at 4300.699 cm-1, from which the inferred line strength agrees well with HITRAN 2016. Meanwhile, a more accurate N2 collisional broadening was provided and the speed-dependent collisional broadening coefficient of this transition was reported for the first time.

18.
Opt Express ; 26(7): 9263-9272, 2018 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-29715880

RESUMEN

A highly sensitive, calibration-free method, wavelength modulation - direct absorption spectroscopy (WM-DAS), is proposed by extracting the characteristic frequencies of modulated laser intensity. This method combines the advantages of measuring absolute absorbance profile from calibration-free DAS with the enhanced noise rejection and high sensitivity of WMS. The preliminary validation experiment of H2O transitions shows that the WM-DAS method improves the accuracy of the absorbance profile measurement with a best-fit standard residual of 4.9 × 10-5. This new method might inspire new approaches to high-precision measurement of spectral line parameters and gas information with weak absorptions or industrial applications.

19.
Am J Bot ; 105(11): 1824-1834, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30418679

RESUMEN

PREMISE OF THE STUDY: To improve our understanding of the patterns and drivers of fleshy fruit phenology, we examined the sequence, patterns across years and locations, and drivers of fruiting times at five botanical gardens on three continents. METHODS: We monitored four stages of fruit phenology for 406 temperate, fleshy-fruited, woody plant species in 2014 and 2015. KEY RESULTS: Across all gardens, ripe fruits were present from May to March of the following year, with peak fruiting durations ranging from under 1 week to over 150 days. Species-level first fruiting and onset of peak fruiting dates were strongly associated with one another within sites and were more consistent between years and sites than the end of peak fruiting and last fruiting date. The order of fruiting among species between years and gardens was moderately consistent, and both peak fruiting times and fruiting durations were found to be phylogenetically conserved. CONCLUSIONS: The consistent order of fruiting among species between years and locations indicates species-specific phenological responses to environmental conditions. Wide variation in fruiting times across species and in the duration of peak fruiting reinforces the importance of understanding how plant phenology impacts dispersers and monitoring the health and consistency of these interactions.


Asunto(s)
Evolución Biológica , Frutas/crecimiento & desarrollo , Magnoliopsida/fisiología , Filogenia
20.
Environ Sci Technol ; 52(19): 11378-11386, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30169957

RESUMEN

There is a rising concern that fine particle (PM2.5) compositions may play an important role in explaining PM2.5-related mortality risks. However, PM2.5 constituents responsible for these risks have not yet been determined. To date, there are few PM2.5 constituent health studies in developing countries. We adopted a time-series approach, using generalized linear regression models to examine associations between short-term exposure to PM2.5 constituents and mortality. We analyzed data stratified by sex and by age groups (<65, 65-74, and >74) from 2013 to 2015 in Beijing, China. We also investigated seasonal patterns of such associations. For a 0 day lag, interquartile range increases in potassium, calcium, magnesium, and organic carbon were associated with 0.51% (95% CI: 0.17-0.85), 2.07% (95% CI: 0.71-3.44), 0.26% (95% CI: 0.08-0.44), and 2.65% (95% CI: 0.18-5.18) increases in respiratory mortality, and sulfate with a 1.57% (95% CI: 0.04-3.12) increase in cardiovascular mortality. In the season-stratified analysis, the association of some constituents (potassium, calcium, magnesium, nitrate, sulfate, and organic carbon) with respiratory mortality appeared to be stronger in cold seasons than in warm seasons. Older adults (65-74) may be susceptible to certain compositions. Our findings provide evidence that link PM2.5 constituents with mortality and suggest that adverse effects vary among constituents in different seasons.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Anciano , Beijing , China , Humanos , Tamaño de la Partícula , Material Particulado , Estaciones del Año
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