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1.
Small ; : e2402748, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898734

RESUMEN

Defect engineering is considered as a flexible and effective mean to improve the performance of Fenton-like reactions. Herein, a simple method is employed to synthesize Co3O4 catalysts with Co-O vacancy pairs (VP) for peroxymonosulfate (PMS) activation. Multi-scaled characterization, experimental, and simulation results jointly revealed that the cation vacancies-VCo contributed to enhanced conductivity and anion vacancies-VO provided a new active center for the 1O2 generation. Co3O4-VP can optimize the O 2p and Co 3d bands with the strong assistance of synergistic double vacancies to reduce the reaction energy barrier of the "PMS → Co(IV) = O → 1O2" pathway, ultimately triggering the stable transition of mechanism. Co3O4-VP catalysts with radical-nonradical collaborative mechanism achieve the synchronous improvement of activity and stability, and have good environmental robustness to favor water decontamination applications. This result highlights the possibility of utilizing anion and cation vacancy engineering strategies to rational design Co3O4-based materials widely used in catalytic reactions.

2.
Mol Phylogenet Evol ; 186: 107860, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37329932

RESUMEN

Species richness is spatially heterogeneous even in the hyperdiverse tropical floras. The main cause of uneven species richness among the four tropical regions are hot debated. To date, higher net diversification rates and/or longer colonization time have been usually proposed to contribute to this pattern. However, there are few studies to clarify the species richness patterns in tropical terrestrial floras. The terrestrial tribe Collabieae (Orchidaceae) unevenly distributes in the tropical regions with a diverse and endemic center in Asia. Twenty-one genera 127 species of Collabieae and 26 DNA regions were used to reconstruct the phylogeny and infer the biogeographical processes. We compared the topologies, diversification rates and niche evolutionary rates of Collabieae and regional lineages on empirical samplings and different simulated samplings fractions respectively. Our results suggested that the Collabieae originated in Asia at the earliest Oligocene, and then independently spread to Africa, Central America, and Oceania since the Miocene via long-distance dispersal. These results based on empirical data and simulated data were similar. BAMM, GeoSSE and niche analyses inferred that the Asian lineages had higher net diversification and niche evolutionary rates than those of Oceanian and African lineages on the empirical and simulated analyses. Precipitation is the most important factor for Collabieae, and the Asian lineage has experienced more stable and humid climate, which may promote the higher net diversification rate. Besides, the longer colonization time may also be associated with the Asian lineages' diversity. These findings provided a better understanding of the regional diversity heterogeneity in tropical terrestrial herbaceous floras.


Asunto(s)
Orchidaceae , Filogenia , Orchidaceae/genética , Filogeografía , Clima Tropical
3.
J Exp Bot ; 72(20): 7092-7106, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34313722

RESUMEN

LATERAL ORGAN BOUNDARIES DOMAIN (LBD) genes encode plant-specific transcription factors that participate in regulating various developmental processes. In this study, we genetically characterized PagLBD3 encoding an important regulator of secondary growth in poplar (Populus alba × Populus glandulosa). Overexpression of PagLBD3 increased stem secondary growth in Populus with a significantly higher rate of cambial cell differentiation into phloem, while dominant repression of PagLBD3 significantly decreased the rate of cambial cell differentiation into phloem. Furthermore, we identified 1756 PagLBD3 genome-wide putative direct target genes (DTGs) through RNA sequencing (RNA-seq)-coupled DNA affinity purification followed by sequencing (DAP-seq) assays. Gene Ontology analysis revealed that genes regulated by PagLBD3 were enriched in biological pathways regulating meristem development, xylem development, and auxin transport. Several central regulator genes for vascular development, including PHLOEM INTERCALATED WITH XYLEM (PXY), WUSCHEL RELATED HOMEOBOX4 (WOX4), Secondary Wall-Associated NAC Domain 1s (SND1-B2), and Vascular-Related NAC-Domain 6s (VND6-B1), were identified as PagLBD3 DTGs. Together, our results indicate that PagLBD3 and its DTGs form a complex transcriptional network to modulate cambium activity and phloem/xylem differentiation.


Asunto(s)
Populus , Cámbium/genética , Cámbium/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Xilema/genética , Xilema/metabolismo
4.
Mol Breed ; 41(6): 37, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37309441

RESUMEN

Sugar metabolism is the most important and core one which drives plant growth and development. Invertases are key enzymes that regulate sugar metabolism. A still-growing number of studies have revealed that invertases play a crucial role in various aspects of plant growth and development. Crop yield is the product of sugar metabolism; it could be deduced that invertase also regulated the yield formation. So we have done a series of research on soluble acid invertase in sweet sorghum from enzyme activity to gene cloning and functional marker development. In this paper, we sequenced full length of SAI-1 gene in 69 grain sorghum parent lines, trying to see how it differs in their gene sequences and their distribution in related hybrid varieties released in the past. To our surprise, the result showed that B-lines and restore lines (R-line) have almost different SAI-1 haplotype distribution. The change of haplotype of SAI-1 gene is associated with yield gain as with grain sorghum breeding progress, which proved that SAI-1 may take a very important role in yield formation. And we also found the SAI-1 gene tends to become shorter as with the breeding advance, which means short sequence in introns, while exon remains unchanged leading to higher gene efficiency. The best SAI-1 haplotype combination of sorghum hybrid was also found for different planting regions. These findings are of great significance for improving breeding efficiency, understanding heterosis, and germplasm enhancement. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01231-2.

5.
BMC Plant Biol ; 19(1): 597, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31888488

RESUMEN

BACKGROUND: Gene flow in plants via pollen and seeds is asymmetrical at different geographic scales. Orchid seeds are adapted to long-distance wind dispersal but pollinium transfer is often influenced by pollinator behavior. We combined field studies with an analysis of genetic diversity among 155 physically mapped adults and 1105 F1 seedlings to evaluate the relative contribution of pollen and seed dispersal to overall gene flow among three sub-populations of the food-deceptive orchid Phalaenopsis pulcherrima on Hainan Island, China. RESULTS: Phalaenopsis pulcherrima is self-sterile and predominantly outcrossing, resulting in high population-level genetic diversity, but plants are clumped and exhibit fine-scale genetic structuring. Even so, we detected low differentiation among sub-populations, with polynomial regression analysis suggesting gene flow via seed to be more restricted than that via pollen. Paternity analysis confirmed capsules of P. pulcherrima to each be sired by a single pollen donor, probably in part facilitated by post-pollination stigma obfuscation, with a mean pollen flow distance of 272.7 m. Despite limited sampling, we detected no loss of genetic diversity from one generation to the next. CONCLUSIONS: Outcrossing mediated by deceptive pollination and self-sterility promote high genetic diversity in P. pulcherrima. Long-range pollinia transfer ensures connectivity among sub-populations, offsetting the risk of genetic erosion at local scales.


Asunto(s)
Flujo Génico , Variación Genética , Orchidaceae/genética , Polinización , China , Dispersión de las Plantas , Polen
6.
Fish Shellfish Immunol ; 94: 739-745, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31561026

RESUMEN

Aeromonas hydrophila is a pathogen that causes high mortality in the grass carp. The complement system, as a frontline defence of innate immunity, plays an important role in the immune response against pathogens. However, the immunity evasion mechanism of A. hydrophila against the complement system of grass carp remains unclear. In this study, we described an additional mechanism used by A. hydrophila GD18 to evade the complement system and survive in grass carp serum. First, A. hydrophila evaded the bactericidal activity of grass carp serum. Second, the haemolytic activity assays showed that A. hydrophila obviously suppressed the alternative pathway, which depended on preventing the formation or disabling the function of the membrane-attack complex (MAC). Further research indicated that A. hydrophila targeted complement C3, the central component of the three complement pathways, and degraded it in the grass carp serum, leading to the inhibition of the complement pathways, which resulted in the serum-resistance of A. hydrophila. Furthermore, cleavage analyses showed that extracellular proteases (ECPases) of A. hydrophila efficiently cleaved purified C3 as well as C3 in grass carp serum. Finally, protease inhibitor studies and mass spectrum analysis identified the secreted metalloprotease elastase (AhE), which was present in large amounts in crude ECPases, as the central molecule responsible for C3 cleavage. Compared to wild strain GD18, the AhE knockout, Δahe was dramatically reduced in the ability of serum resistance. Our findings suggested that A. hydrophila escaped serum-killing by suppressing the complement pathways via the degradation of complement C3 in bony fish, which was related to secreted metalloproteases.


Asunto(s)
Carpas/inmunología , Complemento C3/metabolismo , Enfermedades de los Peces/inmunología , Proteínas de Peces/sangre , Metaloproteasas/metabolismo , Transducción de Señal/inmunología , Aeromonas hydrophila/fisiología , Animales , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria
7.
Molecules ; 22(9)2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28895883

RESUMEN

Oxidative stress and inflammation are hypothesized to contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD). Resveratrol (trans-3,5,4'-trihydroxystilbene) is known for its antioxidant and anti-inflammatory properties. The study aimed to investigate the effects of resveratrol in a rat model with COPD on the regulation of oxidative stress and inflammation via the activation of Sirtuin1 (SIRTl) and proliferator-activated receptor-γ coactivator-1α (PGC-1α). Thirty Wistar rats were randomly divided into three groups: control group, COPD group and resveratrol intervention group. The COPD model was established by instilling with lipopolysaccharide (LPS) and challenging with cigarette smoke (CS). The levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) in serum were measured. The levels of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured. The expression levels of SIRT1 and PGC-1α in the lung tissues were examined by immunohistochemistry as well as real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) and western blotting analysis. After the treatment with resveratrol (50 mg/kg), compared with the COPD group, alleviation of inflammation and reconstruction in the small airways of the lungs were seen. Resveratrol might be correlated not only with the lower level of MDA and the higher activity of SOD, but also with the upregulation of SIRT1 and PGC-1α expression. Resveratrol treatment decreased serum levels of IL-6 and IL-8. Our findings indicate that resveratrol had a therapeutic effect in our rat COPD model, which is related to the inhibition of oxidative stress and inflammatory response. The mechanism may be related to the activation and upgrading of the SIRT1/PGC-1α signaling pathways. Thus resveratrol might be a therapeutic modality in COPD.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Inflamación/metabolismo , Estrés Oxidativo/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Estilbenos/farmacología , Animales , Líquido del Lavado Bronquioalveolar/citología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/patología , Interleucina-6/sangre , Interleucina-6/metabolismo , Interleucina-8/sangre , Interleucina-8/metabolismo , Lipopolisacáridos/efectos adversos , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Malondialdehído/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/patología , Ratas , Resveratrol , Transducción de Señal/efectos de los fármacos , Sirtuina 1/genética , Sirtuina 1/metabolismo , Superóxido Dismutasa/metabolismo
8.
Zhong Yao Cai ; 39(4): 708-12, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30132309

RESUMEN

Objective: To screen the germination and seedling conditions of Trollius chinensis seeds from Chongli county, Zhangjiakou city. To provide the theoretical basis and practical technology for establishing technology system of seedling and cultivation of Trollius chinensis seeds in Zhangjiakou city. Methods: The data were collected and analyzed by the contrast test of greenhouse. Results: The most suitable conditions of Trollius chinensis seedling treatment were as follows, the concentration of GA3 was 800 mg / m L at 4 ℃,and under this condition in infusing for 4 days, and placed in the artificial climate chamber, the temperature was 20 ℃,light treatment for 4 days with 12 h light and 12 h darkness, and sprayed PEG 6000( 30 g / L). Trollius chinesis seeds were sowed on the 4th day, peat soil was selected as matrix, and the germination rate reached more than 85%. Conclusion: According to the characteristics of the seedling appearance and the conditions of the seedlings after transplanting, the seedling growth is robust and the survival rate is much higher.


Asunto(s)
Germinación , Plantones , Ranunculaceae , Semillas , Suelo , Temperatura
9.
Huan Jing Ke Xue ; 44(8): 4271-4278, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37694622

RESUMEN

The current regulatory site investigation employs the J&E model to predict vapor intrusion risk. However, the J&E model assumes that the source concentration is constant for a given exposure period, which is not consistent with the actual site source under depletion. In this study, we compared the differences between the J&E model (constant source), SD source depletion model, and RBCA source depletion model for predicting indoor concentration variation as well as the risk levels during the exposure period with a case study in Beijing. The results showed that the source and indoor air concentrations predicted by the SD and RBCA models showed exponential decreases, whereas those predicted by the J&E model maintained high concentrations throughout the exposure period, which greatly overestimated the risk. The RBCA predicted source depletion at the fastest rate, but the predicted indoor air concentrations were still lower than those of the SD model, which was related to the fact that the RBCA did not consider the effect of buildings on source depletion and did not follow mass conservation. Further, the sensitivity analysis showed that the pressure difference (dP) had the greatest influence on the source concentration in the SD model. For the calculated carcinogenic risk and hazard quotients, the J&E constant source model, the SD source depletion model, and the RBCA source depletion model were ranked in descending order. The results indicated that in general the J&E model was too conservative, the RBCA model may have underestimated risk, and the SD model was more suitable for quantifying vapor intrusion risk in reality.

10.
Microbiol Resour Announc ; 11(4): e0113821, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35357184

RESUMEN

The genome sequence of Achromobacter sp. strain 77, a bacterium isolated from the hyphosphere of Fusarium oxysporum f. sp. cucumerinum, is reported here. Genome sequencing and assembly yielded one chromosome consisting of 5,868,070 bases, with a G+C content of 65.89%.

11.
Front Plant Sci ; 13: 1008198, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36212350

RESUMEN

Sorghum [Sorghum bicolor (L.) Moench] is an important crop for food security in semiarid and arid regions due to its high tolerance to abiotic and biotic stresses and its good performance in marginal lands with relatively low fertility. To deeply understand the interrelationship among sorghum genotype, environment, sowing dates, and densities in the spring sowing early maturing (SSEM) areas of China, and to provide a basis for specifying scientific and reasonable cultural practices, a two-year field experiment was conducted with six popular varieties at six locations. Combined ANOVA showed that the yield difference between years was significant (P<0.05); the yield differences among locations, varieties, sowing dates, and densities were all highly significant (P<0.01). The variety effect was mainly influenced by location, year, sowing dates and their interactions. The sowing effect was mainly influenced by the location, year, variety and their interactions The plant density effect was significantly influenced by location and location-year interaction. Of the contributions of various test factors to yield variance, the location was the largest one (38.18%), followed by variety (12.31%), sowing date (1.53%), density (0.54%), and year (0.09%), with all these single factors accounting for 52.65%. The total contribution of all two-factor interactions accounted for 14.24%, among which the greatest contributor was location-hybrid interaction (8.07%). The total contribution of all three-factor interactions accounted for 14.58%, of which year-location-hybrid interaction was the largest contributor (9.02%). Sowing dates significantly affected model of sorghum growth and development, especially during the late period. The key climatic factors affecting yield were different among the six locations. Weather factors during the grain filling stages contributed much more than those during the early stage to grain yield. Mid-maturing varieties are recommended other than early maturing varieties for the SSEM areas even when late sowing occurs. Sowing as early as possible is recommended for areas with very short frost-free period (Harbin, Tongliao, and Datong). Proper delayed sowing is recommended for areas with a relative long frost-free period (Gongzhuling, Baicheng and Zhangjiakou). This research will provide a conducive reference for sorghum production in similar areas.

12.
Front Plant Sci ; 13: 1076854, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36714717

RESUMEN

Grain sorghum has been a significant contributor to global food security since the prehistoric period and may contribute even more to the security of both food and energy in the future. Globally, precise management techniques are crucial for increasing grain sorghum productivity. In China, with diverse ecological types, variety introduction occasionally occurs across ecological zones. However, few information is available on the effect of ecological type on genotype performance and how plant spacing configuration influences grain yield in various ecological zones. Hence, a series of two-year field experiments were conducted in 2020 and 2021 in four ecological zones of China, from the northeast to the southwest. The experiments included six widely adapted sorghum varieties under six plant spacing configurations (two row spacing modes: equidistant row spacing (60 cm) mode and wide (80 cm)-narrow (40 cm) row spacing mode; three in-row plant spacings: 10 cm, 15 cm, and 20 cm). Our results indicated that ecological type, variety, and plant spacing configuration had a significant effect on sorghum yield. Ecological type contributed the highest proportion to the yield variance (49.8%), followed by variety (8.3%), while plant spacing configuration contributed 1.8%. Sorghum growth duration was highly influenced by the ecological type, accounting for 87.2% of its total variance, whereas plant height was mainly affected by genotype, which contributed 81.6% of the total variance. All test varieties, developed in the south or north, can reach maturity within 94-108 d, just before fall sowing in central China. Generally, sorghum growth duration becomes longer when a variety is introduced from south to north. A late-maturing variety, developed in the spring sowing and late-maturing regions, possibly could not reach maturity in the early-maturing region. The row spacing modes had no significant affect on sorghum yield, but the equal-row spacing mode consistently caused higher yields with only one exception; this might imply that equal-row spacing mode was more advantageous for boosting sorghum yield potential. In contrast, decreasing in-row plant spacing showed significant positive linear associations with sorghum grain yield in most cases. In addition, these results demonstrated that sorghum is a widely adapted crop and enables success in variety introduction across ecological zones.

13.
Mol Phylogenet Evol ; 61(2): 308-20, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21718793

RESUMEN

A molecular analysis was performed on 56 taxa in the orchid genus Cypripedium using nrDNA ITS and five chloroplast regions (trnH-psbA, atpI-atpH, trnS-trnfM, trnL-F spacer, and the trnL intron). The genus Cypripedium was confirmed as monophyletic. Our data provided strong support for monophyletic grouping of eight infrageneric sections (Subtropica, Obtusipetala, Trigonopedia, Sinopedilum, Bifolia, Flabelinervia, Arietinum, and Cypripedium) defined in earlier taxonomic treatments, and paraphyletic grouping of two sections (Irapeana and Retinervi). Within the genus Cypripedium, the first divergent lineage consisted of two Mesomaerican species, and subsequently the Cypripedium debile lineage from eastern Asia was split. Our study did not support the notion that two Asian species (Cypripedium subtropicum and Cypripedium singchii) were closely related to either Mesoamerican Cypripedium irapeanum or North American Cypripedium californicum, as indicated by previous interpretations based on morphological evidences. In addition, one pair of vicariant species, Cypripedium plectrochilum (eastern Asia) and Cypripedium arietinum (North America), unique to section Arietinum, was confirmed. Furthermore, within the monophyletic section Cypripedium two previously recognized subsections, Cypripedium and Macrantha, were shown to be paraphyletic. Our results suggested that this section split into two groups based on distribution (North America vs. Eurasia) instead of such previously used, morphological traits as flower color, and the shape of the lips (labellum) and lateral petals.


Asunto(s)
ADN de Cloroplastos/genética , ADN Espaciador Ribosómico/genética , Evolución Molecular , Orchidaceae/genética , Filogenia , Núcleo Celular/genética , ADN de Plantas/genética , Flores/genética , Orchidaceae/clasificación , Análisis de Secuencia de ADN
14.
Chin J Integr Med ; 27(4): 286-290, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32415645

RESUMEN

OBJECTIVE: To evaluate the effect and safety of cinnamaldehyde on immunosuppressed mice with invasive pulmonary candidiasis. METHODS: An immunosuppressed BALB/c mouse model was established by intraperitoneal administration of cyclophosphamide (200 mg/kg) once daily for 2 days. The immunosuppressed mouse with invasive pulmonary candidiasis model was further established by nasal perfusion of Candida albicans suspension. In the cinnamaldehyde treatment group, immunosuppressed mice with invasive pulmonary candidiasis were orally given cinnamaldehyde 240 mg/(kg·d) for 14 consecutive days. Fluconazole and 0.9% saline were used as the positive and negative controls, respectively. The mice in the cinnamaldehyde safety evaluation group were orally administered cinnamaldehyde 480 mg/(kg·d) for 42 days to observe the safety of the drug. Microscopic identification, fungal culture, histopathological examination, and (1,3)-beta-D-glucans detection were conducted to analyze the effect of cinnamaldehyde on C. albicans. RESULTS: The fungal clearance rate in the cinnamaldehyde treatment group was higher than that in the fluconazole control group (80.00% vs. 56.67%, P<0.05). The level of (1,3)-ß-D-glucan in the cinnamaldehyde treatment group was lower than that in the fluconazole positive control group (1160.62 ±89.65 pg/mL vs. 4285.87 ± 215.62 pg/mL, P<0.05). The survival rate of mice in the cinnamaldehyde safety evaluation group was 100%, and no significant pathological changes of kidney, lung and liver were observed. CONCLUSIONS: Cinnamaldehyde was effective and safe in treating immunosuppressed BALB/c mice with invasive pulmonary candidiasis. It would be a potentially novel drug for anti-candidiasis infection.


Asunto(s)
Candidiasis , Acroleína/análogos & derivados , Animales , Antifúngicos/uso terapéutico , Candida albicans , Candidiasis/tratamiento farmacológico , Pulmón , Ratones , Ratones Endogámicos BALB C
15.
Huan Jing Ke Xue ; 39(12): 5296-5307, 2018 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-30628372

RESUMEN

The land use regression (LUR) model is one of the most important systematic methods to simulate the temporal and spatial differentiation of the atmospheric pollutant concentration. To explore the adaptability of the LUR model to the simulation of air pollutants at the national scale in China and the temporal and spatial variation characteristics of fine air particulate matter (PM2.5) in China in 2015 and its correlation with different geographical elements, we built a LUR model. The LUR model is based on a geographically weighted algorithm using PM2.5 data acquired from the national control monitoring site in 2015 as the dependent variable and applying factors such as the type of land use, altitude, population, road traffic, and meteorological elements as independent variables. Based on model regression mapping, we obtained the distributions of monthly and annual PM2.5 concentrations nationwide in 2015 and analyzed the temporal and spatial variation characteristics of PM2.5 concentrations using the Hu line as a reference line. The results indicate that introducing the geographically weighted algorithm can significantly reduce the residual Moran's Ⅰ of the LUR model, weaken the spatial autocorrelation of residuals, and improve the coefficient of determination R2, which is better to reveal the complex relationship between the spatial distribution and impact factors of PM2.5. Cropland, forest, grass and urban industrial and residential land, and meteorological elements and major roads noticeably impact the PM2.5 concentration. Different spatial distributions of different geographical elements have distinct effects on PM2.5. The PM2.5 shows distinct temporal and spatial differences on both sides of the Hu line. The PM2.5 concentration is relatively high in developed cities with a large population and high industrialization levels. The concentration of PM2.5 is higher in winter and gradually decreases in autumn, spring, and summer.

16.
Carbohydr Res ; 342(17): 2619-27, 2007 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-17765880

RESUMEN

In maize, three isoforms of starch-branching enzyme, SBEI, SBEIIa, and SBEIIb, are encoded by the Sbe1a, Sbe2a, and Amylose extender (Ae) genes, respectively. The objective of this research was to explore the effects of null mutations in the Sbe1a and Ae genes alone and in combination in wx background on kernel characteristics and on the morphology and physical behavior of endosperm starch granules. Differences in kernel morphology and weight, starch accumulation, starch granule size and size distribution, starch microstructure, and thermal properties were observed between the ae wx and sbe1a ae wx plants but not between the sbe1a wx mutants when compared to wx. Starch from sbe1a ae wx plants exhibited a larger granule size with a wider gelatinization temperature range and a lower endotherm enthalpy than ae wx. Microscopy shows weaker iodine staining in sbe1a ae wx starch granules. X-ray diffraction revealed A-type crystallinity in wx and sbe1a wx starches and B-type in sbe1a ae wx and ae wx. This study suggests that, while the SBEIIb isoform plays a dominant role in maize endosperm starch synthesis, SBEI also plays a role, which is only observable in the presence of the ae mutation.


Asunto(s)
Carbohidratos/química , Regulación de la Expresión Génica de las Plantas , Plantas/metabolismo , Zea mays/química , Zea mays/genética , Enzima Ramificadora de 1,4-alfa-Glucano/química , Cristalización , Yodo/química , Rayos Láser , Microscopía de Contraste de Fase , Modelos Biológicos , Mutación , Dispersión de Radiación , Almidón/química , Temperatura , Difracción de Rayos X
17.
World J Gastroenterol ; 23(12): 2175-2184, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28405145

RESUMEN

AIM: To examine the effects of Acanthopanax senticosus polysaccharides (ASPS) on intestinal tight junction (TJ) disruption and nuclear factor-kappa B (NF-κB)/myosin light chain kinase (MLCK) activation in endotoxemia. METHODS: BALB/C mice (6-8-weeks-old) received continuous intragastric gavage of ASPS for 7 d before injection of lipopolysaccharide (LPS), or received ASPS once after LPS injection. Blood and intestinal mucosal samples were collected 6 h after LPS challenge. Clinical symptoms, histological injury, intestinal permeability, TJ ultrastructure, and TJ protein expression were determined. RESULTS: Compared with mice in the LPS group, pretreatment with ASPS improved clinical and histological scores by 390.9% (P < 0.05) and 57.89% (P < 0.05), respectively, and gut permeability change in endotoxemic mice was shown by a 61.93% reduction in reduced leakage of fluorescein isothiocyanate-dextran 6 h after LPS injection (P < 0.05). ASPS pretreatment also prevented LPS-induced TJ ultrastructure breakdown supported by increased electron dense materials between adjoining cells, sustained redistribution and expression of occludin (0.597 ± 0.027 vs 0.103 ± 0.009, P < 0.05) and zonula occludens-1 (0.507 ± 0.032 vs 0.125 ± 0.019, P < 0.05), and suppressed activation of the NF-κB/MLCK pathway indicated by reduced expression of NF-κB, phospho-inhibitor kappa B-alpha, MLCK and phospho-myosin light-chain-2 by 16.06% (P < 0.05), 54.31% (P < 0.05), 66.10% (P < 0.05) and 64.82% (P < 0.05), respectively. CONCLUSION: ASPS pretreatment may be associated with inhibition of the NF-κB/MLCK pathway and concomitant amelioration of LPS-induced TJ dysfunction of intestinal epithelium in endotoxemia.


Asunto(s)
Eleutherococcus/química , Endotoxemia/tratamiento farmacológico , Quinasa de Cadena Ligera de Miosina/metabolismo , FN-kappa B/metabolismo , Polisacáridos/química , Uniones Estrechas/química , Animales , Permeabilidad de la Membrana Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patología , Lipopolisacáridos , Masculino , Ratones , Ratones Endogámicos BALB C , Permeabilidad , Transducción de Señal
18.
BMJ Open ; 6(12): e013409, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27993907

RESUMEN

OBJECTIVES: Despite the vast quantity of research among Chinese female sex workers (FSWs) to address concerns regarding HIV/sexually transmitted infection (STI) risk, there is a paucity of research on issues of sexual and gender-based violence (SGBV) and the missed opportunity for sexual and reproductive health (SRH) promotion among young FSWs. Our research aimed to assess the prevalence and correlates of SGBV among Chinese adolescent FSWs, and to explore SRH service utilisation. DESIGN AND METHODS: A cross-sectional study using a one-stage cluster sampling method was employed. A semistructured questionnaire was administered by trained peer educators or health workers. Multivariable logistic regression was conducted to determine individual and structural correlates of SGBV. SETTING AND PARTICIPANTS: Between July and September 2012, 310 adolescent women aged 15-20 years, and who self-reported having received money or gifts in exchange for sex in the past 6 months were recruited and completed their interview in Kunming, Yunnan Province, China. RESULTS: Findings confirm the high prevalence of SGBV against adolescent FSWs in China, with 38% (118/310) of participants affected in the past year. Moreover, our study demonstrated the low uptake of public health services and high rates of prior unwanted pregnancy (52%; 61/118), abortion (53%; 63/118) and self-reported STI symptoms (84%; 99/118) in participants who were exposed to SGBV. Forced sexual debut was reported by nearly a quarter of FSWs (23%; 70/310) and was independently associated with having had a drug-using intimate partner and younger age (<17 years old) at first abortion. When controlling for potential confounders, having experienced SGBV was associated with frequent alcohol use, having self-reported symptoms of STI, having an intimate partner and having an intimate partner with illicit drug use. CONCLUSIONS: This study calls for effective and integrated interventions addressing adolescent FSWs' vulnerability to SGBV and broader SRH consequences.


Asunto(s)
Aborto Inducido/estadística & datos numéricos , Violencia de Género/estadística & datos numéricos , Embarazo no Deseado , Trabajadores Sexuales/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Adolescente , China/epidemiología , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Análisis Multivariante , Embarazo , Adulto Joven
19.
Artículo en Inglés | MEDLINE | ID: mdl-16121005

RESUMEN

Programmed cell death (PCD) is an integral part of plant development. Flower petal usually has the shortest lifetime among all plant organs. There must be a sensitive, tightly controlled PCD in the life cycle of the flower. To understand its mechanism, the ethylene production rate of petals and its correlation with degree of senescence, 1-aminocyclopropane-1-carboxylate (ACC) synthase gene expression, ACC synthase activity and ACC content were determined through the whole flower development period which was arbitrarily divided into five stages depending on appearance of the flower. The results showed that ethylene was not detectable at stages 1 and 2, appeared at stage 3 and increased at stage 5. Transcript of ACC synthase gene did not accumulate at stages 1 and 2, but did so at stages 3-5, and increased gradually at stage 5. ACC synthase activity and ACC content changed in similar way to ethylene production. Ethylene plays a critical role in initiation of rose flower senescence through regulating petal PCD.


Asunto(s)
Apoptosis/fisiología , Etilenos/metabolismo , Flores/crecimiento & desarrollo , Liasas/genética , Rosa/crecimiento & desarrollo , Apoptosis/genética , Northern Blotting , Flores/genética , Flores/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Liasas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rosa/genética , Rosa/metabolismo
20.
Zhonghua Yan Ke Za Zhi ; 39(9): 533-6, 2003 Sep.
Artículo en Zh | MEDLINE | ID: mdl-14766083

RESUMEN

OBJECTIVE: To study the therapeutic effects of Nd:YAG laser on obstructive diseases of the lacrimal passage. METHODS: 693 eyes in 603 cases with obstructive diseases of lacrimal passage, including obstruction of lacrimal puncta (23 eyes), lacrimal duct (192 eyes), nasolacrimal duct (227 eyes), chronic dacryocystitis (231 eyes), and traumatic laceration of lacrimal canaliculus (20 eyes), were treated by lacrimal plastic operation with Nd:YAG laser and the therapeutic effects were compared among the groups. RESULTS: The cure rates and effective rates of the five diseases were 86.9% and 95.7%, 89.1% and 93.8%, 93.0% and 96.0%, 78.4% and 82.7%, 40.0% and 65.0%, respectively. By Ridit analysis, R +/- S(R) values for each group were 0.921 +/- 0.023, 0.914 +/- 0.009, 0.927 +/- 0.007, 0.856 +/- 0.013, 0.749 +/- 0.055. CONCLUSIONS: The therapeutic effect on chronic dacryocystitis is less than those of obstruction of nasolacrimal duct and lacrimal duct (P < 0.05). The therapeutic effect on traumatic laceration of lacrimal canaliculus is less than that of the other four groups (P < 0.05). Therefore, it should be restricted on indication for the cases of chronic dacryocystitis and traumatic laceration of lacrimal canaliculus.


Asunto(s)
Dacriocistorrinostomía , Terapia por Láser/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Terapia por Láser/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Irrigación Terapéutica
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