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1.
Sci Total Environ ; 700: 134359, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31693952

RESUMO

Ammonia (NH3) emitted from motor vehicles is a by-product of measures taken to reduce emissions of other pollutants (e.g. NOx and CO) and has potentially important environmental impacts. NH3 levels can be impacted by various emission standards. However, there is a lack of investigations of the influences from the implementation of different vehicular emission standards on long-term changes in NH3 emissions. To fill this gap, we estimated the inter-annual NH3 emissions of light-duty gasoline vehicles (LDGVs) under different emission standards (State 0 to State V) from 1999 to 2017 and investigated the emission change characteristics under the rapidly developing Chinese economy. Results showed that the NH3 emissions from LDGVs had a sharp, 42-fold increase (from 1.8Gg to 77.9Gg). However, NH3 emissions per capita have begun to decrease with increases in socioeconomic development, presenting an inverted U-shaped tendency as a function of per capita GDP. Further exploration indicated that the decline in emission factors, as determined by upgrades in emission standards, was the decisive factor in promoting the downward trend in per capita emissions. This suggests that continuously upgrading emission standards has offset the increase in NH3 emissions due to the rapid growth of motor vehicles. Quantitative scenario analysis showed a two-stage impact of emission standards on NH3 emissions: emissions would decrease 77% (48%-90% for different years) if State I and State II were not implemented; while if none of standards were upgraded (State III to State V), NH3 emissions would increase 118% (13%-224% for different years), 2-6 times the impacts from the growth of vehicle population and the decline of vehicle kilometres traveled. The data and findings in this study can provide scientific support for understanding air pollution in urban areas and for formulating further vehicle pollution mitigation measures in China and other countries.

2.
Cereb Cortex ; 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31237323

RESUMO

FOXG1 syndrome is a severe encephalopathy that exhibit intellectual disability, emotional disorder, and limited social communication. To elucidate the contribution of somatostatin-expressing interneurons (SST-INs) to the cellular basis underlying FOXG1 syndrome, here, by crossing SST-cre with a Foxg1fl/fl line, we selectively ablated Foxg1. Loss of Foxg1 resulted in an obvious reduction in the number of SST-INs, accompanied by an altered ratio of subtypes. Foxg1-deficient SST-INs exhibited decreased membrane excitability and a changed ratio of electrophysiological firing patterns, which subsequently led to an excitatory/inhibitory imbalance. Moreover, cognitive defects, limited social interactions, and depression-like behaviors were detected in Foxg1 cKO mice. Treatment with low-dose of clonazepam effectively alleviated the defects. These results identify a link of SST-IN development to the aberrant emotion, cognition, and social capacities in patients. Our findings identify a novel role of Foxg1 in SST-IN development and put new insights into the cellular basis of FOXG1 syndrome.

3.
Nat Cell Biol ; 21(6): 687-699, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160711

RESUMO

We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the critical molecular pathways that predispose their differentiation. EPSCs had enriched molecular signatures of blastomeres and possessed developmental potency for all embryonic and extra-embryonic cell lineages. Here, we report the derivation of porcine EPSCs, which express key pluripotency genes, are genetically stable, permit genome editing, differentiate to derivatives of the three germ layers in chimeras and produce primordial germ cell-like cells in vitro. Under similar conditions, human embryonic stem cells and induced pluripotent stem cells can be converted, or somatic cells directly reprogrammed, to EPSCs that display the molecular and functional attributes reminiscent of porcine EPSCs. Importantly, trophoblast stem-cell-like cells can be generated from both human and porcine EPSCs. Our pathway-inhibition paradigm thus opens an avenue for generating mammalian pluripotent stem cells, and EPSCs present a unique cellular platform for translational research in biotechnology and regenerative medicine.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastômeros/citologia , Blastômeros/metabolismo , Linhagem da Célula/genética , Células-Tronco Embrionárias/citologia , Camadas Germinativas/crescimento & desenvolvimento , Camadas Germinativas/metabolismo , Humanos , Camundongos , Medicina Regenerativa , Transdução de Sinais/genética , Suínos , Trofoblastos/citologia , Trofoblastos/metabolismo
4.
Environ Pollut ; 249: 463-471, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30928518

RESUMO

Civil aircraft emissions during landing and takeoff (LTO) are important air pollutant sources, but have been given insufficient attention in China. Accurate estimation of these emissions is limited by a lack of important parameters, such as detailed flight information and the dynamic time in climb and approach modes during LTO that are dependent on mixing layer height (MLH). We developed a flight-time/flight-height relationship using real-time height information in Aircraft Meteorological Data Relay data, and then calculated the actual time for each flight in those two modes based on the actual MLH from meteorological observation. Hourly emissions of civil aircraft were then estimated based on the database of each flight. Total emissions of NOx, CO, SO2, HC and PM from LTO cycles of domestic flights in China during 2015 were 37.78 Gg, 30.25 Gg, 12.00 Gg, 2.38 Gg and 0.75 Gg, respectively. Substantial monthly, daily and hourly variations of emissions due to the flight schedule as well as MLH were calculated. Large differences were found between the new estimation and emissions calculated based on traditional method. Compared with the emissions estimated based on default parameter obtained from International Civil Aviation Organization, the average difference of annual emission among airports with new estimation for various pollutants was approximately 30.3% in climb mode and 81.4% in approach mode; compared with the emissions estimated based on the method proposed by China National Guide, the average difference of annual emission among airports were 37.4% (NOx), 8.4% (CO), 73.1% (HC) and 58.1% (PM) during LTO process. The monthly airport-specific emissions per LTO were also proposed. These can provide necessary and meaningful support for the revision of the values in National Guide.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Aeronaves/estatística & dados numéricos , Monitoramento Ambiental/métodos , Emissões de Veículos/análise , Aeroportos , China , Humanos , Meteorologia
5.
J Environ Manage ; 234: 424-430, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30640167

RESUMO

Rapid economic development has caused an increase in serious pollution problems due to the ever-increasing use of oil and its products, thus making oil pollution control an urgent task. Studies have shown that large amounts of bacterial-feeding nematodes are present in oil-contaminated soil; their function is as yet unclear. In this experiment, different densities of Caenorhabditis elegans (C. elegans) were inoculated into artificially simulated oil-contaminated soil to examine their effects on microbial activity and the microbial community in oil-contaminated soil. Six treatments were investigated: sterilized oil-contaminated soil as control 1 (FSP), nematode-free soil as control 2 (S), oil-contaminated soil (SP), oil-contaminated soil + 5, 10 or 20 individual C. elegans per gram of dry soil (i.e., SPN5, SPN10, SPN20). Results showed that oil pollution significantly increased the soil basal respiration. However, C. elegans weakened the soil basal respiration to different degrees and soil microbial respiration entropy essentially changed in line with the soil basal respiration. Oil pollution and C. elegans boosted catalase activity in contaminated soil by approximately 64.2-145.1%. Soil urease activity of SPN5, SPN10 and SPN20 was 88.5%, 126.7% and 109.0% stronger, respectively, than that of SP. The inoculation of C. elegans changed the microbial phospholipid fatty acid content in the oil-contaminated soil, including soil bacteria, fungi, actinomycetes, Gram-positive bacteria (G+) and Gram-negative bacteria (G-). Therefore, this research demonstrates that C. elegans can stimulate microbial reproduction in oil-contaminated soil, enhance related soil enzyme activities and regulate soil microbial community structure and diversity, thereby improving the contaminated soil environment and promoting oil degradation.


Assuntos
Microbiota , Nematoides , Poluentes do Solo , Animais , Bactérias , Caenorhabditis elegans , Solo , Microbiologia do Solo
6.
Nat Commun ; 10(1): 470, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30692544

RESUMO

Integrative analysis of multi-omics layers at single cell level is critical for accurate dissection of cell-to-cell variation within certain cell populations. Here we report scCAT-seq, a technique for simultaneously assaying chromatin accessibility and the transcriptome within the same single cell. We show that the combined single cell signatures enable accurate construction of regulatory relationships between cis-regulatory elements and the target genes at single-cell resolution, providing a new dimension of features that helps direct discovery of regulatory patterns specific to distinct cell identities. Moreover, we generate the first single cell integrated map of chromatin accessibility and transcriptome in early embryos and demonstrate the robustness of scCAT-seq in the precise dissection of master transcription factors in cells of distinct states. The ability to obtain these two layers of omics data will help provide more accurate definitions of "single cell state" and enable the deconvolution of regulatory heterogeneity from complex cell populations.


Assuntos
Cromatina/genética , Epigenômica , Regulação da Expressão Gênica , Análise de Célula Única/métodos , Transcriptoma , Cromatina/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Células HCT116 , Células HeLa , Humanos , Células K562 , Sequências Reguladoras de Ácido Nucleico/genética , Análise de Sequência de DNA/métodos
7.
J Invest Surg ; : 1-10, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30430887

RESUMO

AIM: In this study, we examined the effects of branched silicon tube (BST) and temporary closed circle (TCC) in a Beagle dog model of multiple transection of small intestine and discontinuities suspected intestinal necrosis with hemorrhagic shock. MATERIALS AND METHODS: Ten male Beagle dogs were randomly divided into two groups. Hemorrhagic shock was induced by bleeding. Intestine was severed. Suspected intestinal necrotic model by ligating the mesenteric vessels was established, with a small tertiary mesenteric vessel reserved. Fracted intestines were ligated (IL group, n = 5) or reconnected with BST (IR group, n = 5). The abdominal cavity was temporarily closed with TCC. Definitive surgery was conducted after 24 h. RESULTS: There was no statistical difference between two groups in the weight of dogs, their blood loss, fluid resuscitation, operation time of early emergency treatment (EET). After definitive surgery, all dogs in IR group and 3 dogs in IL groups were alive. 18 (90%) suspicious necrotic intestinal segments in IL group became necrotic, but 20 (80%) segments in IR group didn't develop obvious changes (p < 0.01). From 2 h after EET, the endotoxin concentration in IL group was significantly higher than that in IR group (133.87 ± 43.73 vs. 56.31 ± 24.70 pg/ml, p < 0.01). Microscopic examination revealed that much more severe damage occurred in the suspicious necrotic intestinal segments in IL group. CONCLUSION: Both reconnecting intestine with BST and temporary abdominal closure with TCC are viable methods of damage control for multiple discontinuous intestinal injuries.

8.
Pain Physician ; 21(5): E555-E564, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30282403

RESUMO

BACKGROUND: Over-expression of spinal protein kinase Cγ(PKCγ) contributes to the induction of persistent bilateral hyperalgesia following inflammatory injury, yet the role of spinal PKCγ in short- and long-lasting pain behavior is poorly understood. OBJECTIVE: This study aimed to characterize the contribution of spinal PKCγ to spontaneous pain and long-lasting bilateral hyperalgesia in formalin-induced inflamed mice using pharmacological inhibition. STUDY DESIGN: Laboratory animal study. SETTING: The study was performed in the Department of Human Anatomy and K.K. Leung Brain Research Centre, Preclinical School of Medicine, the Fourth Military Medical University (Xi'an, China) and the Department of Anesthesiology, Fuzhou General Hospital (Fuzhou, China). METHODS: Male mice were unilaterally intraplantarly injected with formalin to induce inflammatory pain. Spontaneous pain behaviors, including flinches and lickings, were recorded by off-line video during the first hour post-injection and counted. Using von Frey tests, long-lasting bilateral mechanical paw withdrawal thresholds were determined before injection and at indicated time points thereafter. Temporal expression of spinal PKCγ was observed by immunohistochemical staining. For pharmacological inhibition, mice were treated daily with intrathecal Tat carrier or selective PKCγ inhibitor KIG31-1, from 1 hour prior to 10 days after formalin injection. Spontaneous pain behaviors and long-lasting bilateral mechanical hyperalgesia were assessed. Spinal PKCγ expression was also observed by using immunohistochemical staining and western blot. RESULTS: The number of PKCγ-immunoreactive (ir) spinal neurons was significantly higher at 10 days, but not 2 hours, after formalin intraplantar injection, and accompanied by long-lasting bilateral hyperalgesia. Furthermore, long-lasting bilateral hyperalgesia could be reversed by pharmacological inhibition of over-expressed spinal PKCγ; however, pretreating with intrathecal KIG31-1 showed no antinociceptive effects on short-term spontaneous pain behaviors. LIMITATIONS: All results were obtained from the mice and no PKCγ inhibitors were available through clinical practice. Therefore, it remains difficult to draw definitive connections between animal research and human application. CONCLUSION: Our findings suggest that spinal PKCγ plays a predominant role in long-lasting bilateral hyperalgesia, but not in the spontaneous pain behaviors induced by formalin. KEY WORDS: Formalin, spontaneous pain, mechanical hyperalgesia, protein kinase C gamma, KIG31-1, mice.

9.
Environ Sci Pollut Res Int ; 25(32): 32709-32720, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30244442

RESUMO

Large amounts of air pollutants emitted from massive coal combustion result in the air quality deterioration and threaten public health in China. To improve air quality, the Chinese government released the coal cap policy to reduce coal consumption. So it is important and necessary to understand the possible environmental impact and relevant health benefits from the coal cap policy. The purpose of this paper is to quantify the air quality improvement and to evaluate the health benefits from the implementation of the coal cap policy, with the Beijing-Tianjin-Hebei (BTH) region as the study area. The results showed that the emissions of SO2, NOx, CO, VOCs, PM10, and PM2.5 could be reduced by 20-40% in the BTH region in 2020 and all pollutants from industrial boilers notably decreased. Under the coal cap policy, the PM2.5 concentration in the whole region would fall by 11.27%, and the total economic benefit from health impacts could achieve 26.61 (13.29 to 39.14) billion RMB (3.9 billion USD) in the BTH region in 2020, accounting for 0.43% (0.21 to 0.63%) of regional GDP in 2013. This study demonstrated the quantification of environmental effect and health benefit from the coal cap policy, which could be used for the complete cost-benefit analysis and provide the sufficient support for policy makers to implement the coal cap policy in the BTH region and other areas of China.

10.
Gigascience ; 7(11)2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239706

RESUMO

Background: Investigating cell fate decision and subpopulation specification in the context of the neural lineage is fundamental to understanding neurogenesis and neurodegenerative diseases. The differentiation process of neural-tube-like rosettes in vitro is representative of neural tube structures, which are composed of radially organized, columnar epithelial cells and give rise to functional neural cells. However, the underlying regulatory network of cell fate commitment during early neural differentiation remains elusive. Results: In this study, we investigated the genome-wide transcriptome profile of single cells from six consecutive reprogramming and neural differentiation time points and identified cellular subpopulations present at each differentiation stage. Based on the inferred reconstructed trajectory and the characteristics of subpopulations contributing the most toward commitment to the central nervous system lineage at each stage during differentiation, we identified putative novel transcription factors in regulating neural differentiation. In addition, we dissected the dynamics of chromatin accessibility at the neural differentiation stages and revealed active cis-regulatory elements for transcription factors known to have a key role in neural differentiation as well as for those that we suggest are also involved. Further, communication network analysis demonstrated that cellular interactions most frequently occurred in the embryoid body stage and that each cell subpopulation possessed a distinctive spectrum of ligands and receptors associated with neural differentiation that could reflect the identity of each subpopulation. Conclusions: Our study provides a comprehensive and integrative study of the transcriptomics and epigenetics of human early neural differentiation, which paves the way for a deeper understanding of the regulatory mechanisms driving the differentiation of the neural lineage.

11.
J Environ Manage ; 225: 25-31, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071364

RESUMO

The coal cap policy is one of the most important measures to address the severe air pollution in China. To quantify the impact of the coal cap policy on emissions reduction, we designed four scenarios to predict the effect of energy saving and pollutant emissions reduction from coal-fired stationary sources in the BTH (Beijing-Tianjin-Hebei) region from 2014 to 2030. The results demonstrated that the coal cap strategy would significantly affect energy consumption structure and result in 15% of energy savings in 2020 and 25% in 2030. Moreover, the reduction potential of main pollutants from stationary coal combustion sources would achieve 36-45% in 2020 and 60-79% in 2030 relative to BAU (Business As Usual). For the whole BTH region the BPE (Backward Productivity Elimination) scenario could get a better effect for SO2 and NOX than CES (Clean Energy Strategy) scenario, while the effect is opposite for CO and PM2.5, and similar for VOCs and PM10. For Beijing, there would be very significant reduction for all pollutants under the CES scenario. For Tianjin and Hebei, there is little difference in the pollutants reduction between the BPE and CES scenarios. Power plants and industrial boilers are major contributors under the BPE scenario, and emissions from the heating boilers and residential sources are greatly reduced under the CES scenario. The findings in this study are of considerable value for the policymakers to implementing the coal cap policy in BTH region and other Chinese cities.


Assuntos
Poluentes Atmosféricos , Carvão Mineral , Monitoramento Ambiental , Poluição do Ar , Pequim , China , Cidades
12.
Cereb Cortex ; 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29912324

RESUMO

Abnormalities in cortical interneurons are closely associated with neurological diseases. Most patients with Foxg1 syndrome experience seizures, suggesting a possible role of Foxg1 in the cortical interneuron development. Here, by conditional deletion of Foxg1, which was achieved by crossing Foxg1fl/fl with the Gad2-CreER line, we found the postnatal distributions of somatostatin-, calretinin-, and neuropeptide Y-positive interneurons in the cortex were impaired. Further investigations revealed an enhanced dendritic complexity and decreased migration capacity of Foxg1-deficient interneurons, accompanied by remarkable downregulation of Dlx1 and CXCR4. Overexpression of Dlx1 or knock down its downstream Pak3 rescued the differentiation detects, demonstrated that Foxg1 functioned upstream of Dlx1-Pak3 signal pathway to regulate the postnatal development of cortical interneurons. Due to the imbalanced neural circuit, Foxg1 mutants showed increased seizure susceptibility. These findings will improve our understanding of the postnatal development of interneurons and help to elucidate the mechanisms underlying seizure in patients carrying Foxg1 mutations.

13.
J Org Chem ; 83(12): 6805-6814, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29763306

RESUMO

A practical palladium-mediated cascade Tsuji-Trost reaction/Heck coupling of N-Ts o-bromoanilines with 4-acetoxy-2-butenonic acid derivatives using a Pd(OAc)2/P( o-tol)3/DIPEA system is described for a straightforward synthesis of indole-3-acetic acid derivatives. This methodology was successfully applied to synthesize various substituted indole/azaindole-3-acetic acid derivatives and Almotriptan, which is a drug for the acute treatment of migraines. Moreover, a plausible cyclization mechanism has been proposed.

14.
PLoS One ; 13(5): e0198189, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29795685

RESUMO

Urban extent data play an important role in urban management and urban studies, such as monitoring the process of urbanization and changes in the spatial configuration of urban areas. Traditional methods of extracting urban-extent information are primarily based on manual investigations and classifications using remote sensing images, and these methods have such problems as large costs in labor and time and low precision. This study proposes an improved, simplified and flexible method for extracting urban extents over multiple scales and the construction of spatiotemporal models using DMSP/OLS nighttime light (NTL) for practical situations. This method eliminates the regional temporal and spatial inconsistency of thresholding NTL in large-scale and multi-temporal scenes. Using this method, we have extracted the urban extents and calculated the corresponding areas on the county, municipal and provincial scales in China from 2000 to 2012. In addition, validation with the data of reference data shows that the overall accuracy (OA), Kappa and F1 Scores were 0.996, 0.793, and 0.782, respectively. We increased the spatial resolution of the urban extent to 500 m (approximately four times finer than the results of previous studies). Based on the urban extent dataset proposed above, we analyzed changes in urban extents over time and observed that urban sprawl has grown in all of the counties of China. We also identified three patterns of urban sprawl: Early Urban Growth, Constant Urban Growth and Recent Urban Growth. In addition, these trends of urban sprawl are consistent with the western, eastern and central cities of China, respectively, in terms of their spatial distribution, socioeconomic characteristics and historical background. Additionally, the urban extents display the spatial configurations of urban areas intuitively. The proposed urban extent dataset is available for download and can provide reference data and support for future studies of urbanization and urban planning.

16.
Sci Total Environ ; 630: 72-82, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29475115

RESUMO

Beijing, the capital of China, suffers from severe atmospheric aerosol pollution; nevertheless, a comprehensive study of the constituents and sources of PM1 is still lacking, and the differences between PM1 and PM2.5 are still unclear. In this study, an intensive observation was conducted to reveal the pollution characteristics of PM1 and PM2.5 in Beijing in autumn. Positive matrix factorization (PMF), backward trajectories and a potential source contribution function (PSCF) model were used to identify the source categories and source areas of PM1 and PM2.5. The results showed that the average concentrations of PM1 and PM2.5 reached 78.20µg/m3 and 95.47µg/m3 during the study period, respectively. PM1 contributed greatly to PM2.5. The PM1/PM2.5 value increased from 73.6% to 90.1% with PM1 concentration growing from <50µg/m3 to >150µg/m3. Higher secondary inorganic aerosol (SIA) proportions (31.3%-70.8%) were found in PM1. The higher fraction of SIA, OC, EC and typical elements in PM1 illustrated that anthropogenic components accumulated more in smaller size particles. Three typical weather patterns causing the heavy pollution in autumn were found as follows: (1) Siberian high and uniform high pressure field, (2) cold front and low-voltage system, and (3) uniform low pressure field. A PMF analysis indicated that secondary aerosols and coal combustion, vehicle, industry, biomass burning, and dust were the important sources of PM, accounting for 53.8%, 8.0%, 13.0%, 13.2% and 12.0% of PM1, respectively, and for 47.5%, 9.9%, 12.4%, 8.4% and 21.8% of PM2.5, respectively. The HYSPLIT and chemical components analysis indicated the potential contribution from biomass burning and fertilization ammonia emissions to PM1 in autumn. The source areas were similar for PM1 and PM1-2.5 under general polluted conditions, but during the heavily polluted periods, the source areas were distributed in farther regions from Beijing for PM1 than for PM1-2.5.

17.
Int J Mol Sci ; 19(1)2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29351213

RESUMO

It is well known that cyclinB3 (cycB3) plays a key role in the control of cell cycle progression. However, whether cycB3 is involved in stem cell fate determination remains unknown. The Drosophila ovary provides an exclusive model for studying the intrinsic and extrinsic factors that modulate the fate of germline stem cells (GSCs). Here, using this model, we show that DrosophilacycB3 plays a new role in controlling the fate of germline stem cells (GSC). Results from cycB3 genetic analyses demonstrate that cycB3 is intrinsically required for GSC maintenance. Results from green fluorescent protein (GFP)-transgene reporter assays show that cycB3 is not involved in Dad-mediated regulation of Bmp signaling, or required for dpp-induced bam transcriptional silencing. Double mutants of bam and cycB3 phenocopied bam single mutants, suggesting that cycB3 functions in a bam-dependent manner in GSCs. Deficiency of cycB3 fails to cause apoptosis in GSCs or influence cystoblast (CB) differentiation into oocytes. Furthermore, overexpression of cycB3 dramatically increases the CB number in Drosophila ovaries, suggesting that an excess of cycB3 function delays CB differentiation. Given that the cycB3 gene is evolutionarily conserved, from insects to humans, cycB3 may also be involved in controlling the fate of GSCs in humans.


Assuntos
Diferenciação Celular/genética , Ciclina B/genética , Proteínas de Drosophila/genética , Drosophila/genética , Células Germinativas/crescimento & desenvolvimento , Animais , Apoptose/genética , Drosophila/citologia , Drosophila/crescimento & desenvolvimento , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/citologia , Ovário/citologia , Ovário/crescimento & desenvolvimento , Proteômica , Células-Tronco/citologia
18.
Sci Total Environ ; 626: 274-286, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29353777

RESUMO

Domestic biomass burning (DBB) influences both indoor and outdoor air quality due to the multiple pollutants released during incomplete and inefficient combustion. The emissions are not well quantified because of insufficient information, which were the key parameters related to fuel consumption estimation, such as province- and year-specific percentage of domestic straw burning (Pstraw) and firewood consumption (Fc). In this study, we established the quantitative relationship between rural-related socioeconomic parameters (e.g., rural per-capita income and rural Engel's coefficient) and Pstraw/Fc. DBB emissions, including 12 crop straw types and firewood for 12 kinds of pollutants in China during the period 1995-2014, were estimated based on fuel-specific emission factors and detailed fuel consumption data. The results revealed that the national emissions generally increased initially and then decreased with the turning point around 2007-2008. Firewood burning was the major source of the NH3 and BC emissions; straw burning contributed more to SO2, NMVOC, CO, OC, and CH4 emissions; while the major contributor changed from firewood to domestic straw burning for NOx, PM10, PM2.5, CO2, and Hg emissions. The emission trends varied among the 31 provinces. The major agricultural regions of north-eastern, central, and south-western China were always characterized by high emissions. The spatial variation mainly occurred in the northeast and north China (increase), and central-south and coastal regions of China (decrease).

19.
Cell Biol Int ; 42(7): 769-780, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29110400

RESUMO

The Drosophila ovary provides an attractive model for studying the extrinsic or intrinsic factors that regulate the fate of germline stem cells (GSCs). Using this model, we identified a new role for Drosophila spaghetti (spag), encoding a homolog of human RNA polymerase II-associated protein 3 (RPAP3), in regulating the fate of ovarian GSCs. Results from spag knockdown and genetic mosaic studies suggest that spag functions as an intrinsic factor for GSCs maintenance. Loss of Spag by, either spag RNAi or null mutation failed to trigger apoptosis in ovarian GSCs. Overexpression of spag led to negligible increases in the number of GSC/Cystoblast (CB) cells, suggesting that an excess of Spag is not sufficient to accelerate the proliferation of GSCs or delay CBs' differentiation. Our study provides evidence supporting that spag is involved in adult stem cells maintenance. In addition, the RNAi screen results showed that knockdown of Hsp90, one of known Spag interacting partners, led to loss of ovarian GSCs in Drosophila. Heterozygous mutations in hsp90 (hsp90/+) dramatically accelerated the GSC loss in spag RNAi ovaries, suggesting that the Spag-contained complex possibly plays an essential role in controlling the GSCs fate.


Assuntos
Proteínas de Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/citologia , Chaperonas Moleculares/genética , Ovário/metabolismo , Células-Tronco/citologia , Animais , Diferenciação Celular/genética , Linhagem da Célula , Drosophila/genética , Feminino , Humanos
20.
J Biophotonics ; 11(4): e201700139, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29131523

RESUMO

Tissue-depolarization and linear-retardance are the main polarization characteristics of interest for bulk tissue characterization, and are normally interpreted from Mueller polarimetry. Stokes polarimetry can be conducted using simpler instrumentation and in a shorter time. Here, we use Stokes polarimetric imaging with circularly polarized illumination to assess the circular-depolarization and linear-retardance properties of tissue. Results obtained were compared with Mueller polarimetry in transmission and reflection geometry, respectively. It is found that circular-depolarization obtained from these 2 methods is very similar in both geometries, and that linear-retardance is highly quantitatively similar for transmission geometry and qualitatively similar for reflection geometry. The majority of tissue circular-depolarization and linear-retardance image information (represented by local image contrast features) obtained from Mueller polarimetry is well preserved from Stokes polarimetry in both geometries. These findings can be referred to for further understanding tissue Stokes polarimetric data, and for further application of Stokes polarimetry under the circumstances where short acquisition time or low optical system complexity is a priority, such as polarimetric endoscopy and microscopy.

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