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1.
Bioresour Technol ; 399: 130549, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38461869

RESUMEN

The biogas upgrading process through bioconversion of CO2 to CH4 by hydrogenotrophic methanogens is an attractive strategy for energy decarbonation. Many studies have optimized operational parameters to improve key performance indicators such as CH4% and H2 utilization efficiency. However, inconsistent laboratory conditions make it challenging to compare results. Existing models for analyzing operating conditions can only assess the impact of individual conditions and lack the ability to simultaneously optimize multiple conditions. To address this, two XGBoost models were built with R2 of 0.779 and 0.903 with data collected from literatures and were embedded into multi-objective partitive swarm optimization algorithm to optimal operating conditions. Predictions were compared with experimental validations under optimized conditions, revealing an 8.50% and 2.95% relative error in CH4% and H2 conversion rate, respectively. This approach streamlines biogas upgrading processes, offering a data-driven solution to enhance efficiency and consistency in the pursuit of sustainable methane production.


Asunto(s)
Biocombustibles , Reactores Biológicos , Dióxido de Carbono , Metano , Hidrógeno , Hidrolasas
2.
Huan Jing Ke Xue ; 45(2): 952-960, 2024 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-38471933

RESUMEN

In order to clarify the impact of no-tillage on the quality of farmland soil aggregates in China and promote the adaptive application of no-tillage practices, a Meta-analysis was conducted by collecting data from 116 published studies. The effects of no-tillage on aggregate size distribution, mean weight diameter (MWD), and aggregate-associated C were studied. The results showed that compared with that under tillage, no-tillage significantly increased the proportion of macroaggregates (10.9%) and MWD (12.8%) and decreased the proportion of clay and silt (-15.5%) but had no significant effect on soil microaggregate and aggregate-associated C. The subgroup and Meta regression analysis showed that no-tillage significantly increased the proportion of macroaggregates in Northwest China (17.6%) and MWD in North China (15.4%). In upland and clay loam, no-tillage increased MWD by 12.6% and 18.4%, respectively. The effect of no-tillage on increasing the proportion of macroaggregates increased with the soil pH. When straw returned, no-tillage significantly increased the proportion of macroaggregates (9.6%) and MWD (11.6%), but no significant effect of no-tillage on aggregates was found after straw removal. Regarding test duration, short-term ( < 5 a) no-tillage could significantly increase the proportion of macroaggregates, whereas long-term ( > 10 a) no-tillage could improve the MWD. In different soil layers, no-tillage could only significantly improve the aggregate size distribution and MWD in topsoil (0-20 cm) but had no effect in subsoil ( > 20 cm). In summary, no-tillage could improve aggregate size distribution and stability but had no effect on aggregate-associated C. Production region, soil properties, field management methods, and other factors should be fully considered in production practice to effectively improve the quality of soil aggregates.

3.
Bioresour Technol ; 394: 130260, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38151211

RESUMEN

Biogas upgrading via CO2 conversion to CH4 is an emerging technology for renewable natural gas production and carbon management, but its development is limited by the low H2 gas to liquid phase transfer. Herein, an innovative biogas upgrading system employing a three-phase design was studied for CO2 conversion with H2 supply via gas-permeable membrane. The system produced biogas consisted of 74.1 ± 7.1 % CH4 and 25.9 ± 7.1 % CO2 with intermittent injection of H2. When H2 supply was continuous, the CH4 content increased to 91.6 ± 2.2 % at a H2:CO2 ratio of 4.4. Although a higher ratio of 5.5 could result in a higher CH4 percentage of 95.2 ± 2.5 %, biogas production rate started to decrease. The removal efficiency of organic contents remained above 90 % throughout the experiment. Microbial community analysis corroborated the findings, showing that hydrogenotrophic Methanobacteriaceae was more prevalent in the biofilm (71.9 %) compared to that in anaerobic digestion (15.8 %) and effluent (14.1 %).


Asunto(s)
Biocombustibles , Reactores Biológicos , Hidrógeno , Dióxido de Carbono , Metano
4.
Ann Transl Med ; 11(2): 34, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36819593

RESUMEN

Background: Irritable bowel syndrome (IBS) is a common gastrointestinal disease. Emerging studies have demonstrated that microRNAs (miRNAs) are commonly dysregulated in patients with IBS, and aberrant miRNAs are implicated in IBS occurrence. Although miR-155-5p participates in inflammatory bowel disease (IBD) and intestinal barrier dysfunction, the role of miR-155-5p in IBS is unclear. Methods: In the present study, colon samples were obtained from IBS patients and IBS mice induced by trinitrobenzenesulfonic acid (TNBS), and the levels of miR-155-5p, claudin-1 (CLDN1), and zonula occludens-1 (ZO-1) were assessed using quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical analysis. The regulatory role of miR-155-5p in CLDN1 and ZO-1 expression was validated using dual luciferase reporter assay. Results: We found that miR-155-5p levels were upregulated in colon samples of IBS patients and mice compared with healthy subjects and normal mice, respectively. Meanwhile, the levels of CLDN1 and ZO-1 were decreased in colon samples of IBS patients and mice. Importantly, forced expression of miR-155-5p inhibited CLDN1 and ZO-1 expression. In IBS mice, intraperitoneal injection with miR-155-5p inhibitor increased CLDN1 and ZO-1 expression in intestinal mucosal epithelium, enhanced visceral response thresholds, and decreased myeloperoxidase (MPO) activity. Conclusions: In summary, these results suggested that miR-155-5p participated in the pathogenesis of IBS, at least in part by inhibiting CLDN1 and ZO-1 expression, indicating that miR-155-5p may be a potential therapeutic target for IBS.

5.
Environ Sci Technol ; 56(6): 3564-3574, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35226478

RESUMEN

The stability of RNA in aqueous systems is critical for multiple environmental applications including evaluating the environmental fate of RNA interference pesticides and interpreting viral genetic marker abundance for wastewater-based epidemiology. In addition to biological processes, abiotic reactions may also contribute to RNA loss. In particular, some metals are known to dramatically accelerate rates of RNA hydrolysis under certain conditions (i.e., 37 °C or higher temperatures, 0.15-100 mM metal concentrations). In this study, we investigated the extent to which metals catalyze RNA hydrolysis under environmentally relevant conditions. At ambient temperature, neutral pH, and ∼10 µM metal concentrations, we determined that metals that are stronger Lewis acids (i.e., lead, copper) catalyzed single-stranded (ss)RNA, whereas metals that are weaker Lewis acids (i.e., zinc, nickel) did not. In contrast, double-stranded (ds)RNA resisted hydrolysis by all metals. While lead and copper catalyzed ssRNA hydrolysis at ambient temperature and neutral pH values, other factors such as lowering the solution pH and including inorganic and organic ligands reduced the rates of these reactions. Considering these factors along with sub-micromolar metal concentrations typical of environmental systems, we determined that both ssRNA and dsRNA are unlikely to undergo significant metal-catalyzed hydrolysis in most environmental aqueous systems.


Asunto(s)
Cobre , ARN , Catálisis , Hidrólisis , Ácidos de Lewis , Metales
6.
Sci Total Environ ; 777: 146077, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33684756

RESUMEN

Hydrothermal conversion (HTC) is a promising technology for the treatment of dewatered sewage sludge to produce bio-fuels including bio-oil and hydrochar. At the same time, a huge amount of wastewater (HTCWW) was produced. The present study investigated the organic compositions of HTCWW obtained at different HTC temperatures (170-320 °C) and volatile fatty acids (VFAs) yields through anaerobic fermentation. Results showed that the highest VFAs yield of 0.59 gCODVFA/gCOD was obtained from HTCWW obtained at 170 °C (HTCWW 170). Higher amount of easily biodegradable organics including proteins and carbohydrates were present in HTCWW 170 °C, which resulted in the highest VFAs yields. With the increase of HTC temperature, recalcitrant organic compounds were produced as revealed by 3D-EEM and GC-MS analysis, which resulted in lower VFAs yields. Furthermore, microbial analysis showed that different compositions in the HTCWW led to the enrichment of different microbial communities, which affected the VFAs yields.


Asunto(s)
Microbiota , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Ácidos Grasos Volátiles , Fermentación , Concentración de Iones de Hidrógeno , Aguas Residuales
7.
PLoS One ; 15(9): e0238760, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32886711

RESUMEN

In this study, we ascertained the chest CT data of 60 patients admitted to 3 hospitals in Chongqing with confirmed COVID-19. We conducted anatomical and pathological analyses to elucidate the possible reasons for the distribution, morphology, and characteristics of COVID-19 in chest CT. We also shared a semiquantitative scoring of affected lung segments, which was recommended by our local medical association. This scoring system was applied to quantify the severity of the disease. The most frequent imaging findings of COVID-19 were subpleural ground glass opacities and consolidation; there was a significant difference in semiquantitative scores between the early, progressive, and severe stages of the disease. We conclude that the chest CT findings of COVID-19 showed certain characteristics because of the anatomical features of the human body and pathological changes caused by the virus. Therefore, chest CT is a valuable tool for facilitating the diagnosis of COVID-19 and semiquantitative scoring of affected lung segments may further elucidate diagnosis and assessment of disease severity. This will assist healthcare workers in diagnosing COVID-19 and assessing disease severity, facilitate the selection of appropriate treatment options, which is important for reducing the spread of the virus, saving lives, and controlling the pandemic.


Asunto(s)
Infecciones por Coronavirus/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Neumonía Viral/diagnóstico por imagen , Tomografía Computarizada Espiral/normas , Adolescente , Adulto , Anciano , COVID-19 , Niño , Infecciones por Coronavirus/patología , Femenino , Humanos , Pulmón/patología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/patología , Índice de Severidad de la Enfermedad , Tomografía Computarizada Espiral/métodos
8.
Int J Pharm X ; 1: 100027, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31517292

RESUMEN

Ethosomes are widely used to promote transdermal permeation of both lipophilic and hydrophilic drugs, but the mechanism of interaction between the ethosomes and the skin remains unclear. In this work, it was exploded with several technologies and facilities. Firstly, physical techniques such as attenuated total reflectance fourier-transform infrared and laser confocal Raman were used and the results indicated that the phospholipids configuration of stratum corneum changes from steady state to unstable state with the treatment of ethosomes. Differential scanning calorimetry reflected the thermodynamics change in stratum corneum after treatment with ethosomes. The results revealed that the skin of Bama mini-pigs, which is similar to human skin, treated by ethosomes had a relatively low Tm and enthalpy. Scanning electron microscopy and transmission electron microscopy showed that the microstructure and ultrastructure of stratum corneum was not damaged by ethosomes treatment. Furthermore, confocal laser scanning microscopy revealed that lipid labeled ethosomes could penetrate the skin via stratum corneum mainly through intercellular route, while during the process of penetration, phospholipids were retained in the upper epidermis. Cell experiments confirmed that ethosomes were distributed mainly on the cell membrane. Further study showed that only the drug-loaded ethosomes increased the amount of permeated drug. The current study, for the first time, elucidated the mechanistic behavior of ethosomes in transdermal application from molecular configuration, thermodynamic properties, ultrastructure, fluorescent labeling and cellular study. It is anticipated that the approaches and results described in the present study will benefit for better design of drug-loaded ethosomes.

9.
Chemosphere ; 228: 619-628, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31059960

RESUMEN

The recovery of phosphorus from sewage sludge was critical due to the depletion of phosphate ore. The present research aims to identify the phosphorus speciation and reveal the phosphorus transformation mechanism of dewatered sewage sludge during hydrothermal conversion (HTC) process, as well as to achieve the high efficiency recovery of phosphorus. Multiple analysis of SMT method, VK diagram, XANES and NMR showed that most phosphorus (>80%) was transferred to the hydrochar and presented as inorganic phosphorus (IP) after the HTC process. A dehydration trend was observed of the HTC process with the increase of sub-critical temperature. Ca-associated phosphorus increased significantly as the temperature increased. The Pyro-P gradually transformed to Ortho-P with the increase of HTC temperature and disappeared at 320 °C. The addition of HCl (6.13 and 12.3 mmol/g) in the HTC process resulted in a high percentage (>80%) of phosphorus transferred to the aqueous phase, and the bioavailability of the residual phosphorus increased significantly. The recovery rate of phosphorus could achieve 98.37% at the pH of 7.52, with the struvite purity of 90.41%. The results of this study provide new insights into the selective transfer of phosphorus in dewatered sludge by HTC process, in addition to some efficient ways for the utilisation of the HTC products.


Asunto(s)
Fósforo/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Espectroscopía de Resonancia Magnética , Estruvita , Temperatura , Espectroscopía de Absorción de Rayos X
10.
Hepatobiliary Pancreat Dis Int ; 17(6): 510-516, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30135046

RESUMEN

BACKGROUD: Transarterial chemoembolization (TACE) is the primary palliative treatment for patients with unresectable hepatocellular carcinoma (HCC). However, it is often accompanied by postoperative pain which hinder patient recovery. This study was to examine whether preemptive parecoxib and sufentanil-based patient controlled analgesia (PCA) could improve the pain management in patients receiving TACE for inoperable HCC. METHODS: From June to December 2016, 84 HCC patients undergoing TACE procedure were enrolled. Because of the willingness of the individuals, it is difficult to randomize the patients to different groups. We matched the patients' age, gender and pain scores, and divided the patients into the multimodal group (n = 42) and control group (n = 42). Patients in the multimodal group received 40 mg of parecoxib, 30 min before TACE, followed by 48 h of sufentanil-based PCA. Patients in the control group received a routine analgesic regimen, i.e., 5 mg of dezocine during operation, and 100 mg of tramadol or equivalent intravenous opioid according to patient's complaints and pain intensity. Postoperative pain intensity, percentage of patients as per the pain category, adverse reaction, duration of hospital stay, cost-effectiveness, and patient's satisfaction were all taken into consideration when evaluated. RESULTS: Compared to the control group, the visual analogue scale scores for pain intensity was significantly lower at 2, 4, 6, and 12 h (all P < 0.05) in the multimodal group and a noticeably lower prevalence of post-operative nausea and vomiting in the multimodal group (31.0% vs. 59.5%). Patient's satisfaction in the multimodal group was also significantly higher than that in the control group (95.2% vs. 69.0%). No significant difference was observed in the duration of hospital stay between the two groups. CONCLUSION: Preemptive parecoxib and sufentanil-based multimodal analgesia regime is a safe, efficient and cost-effective regimen for postoperative pain control in HCC patients undergoing TACE.


Asunto(s)
Analgesia Controlada por el Paciente , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Dolor Postoperatorio/terapia , Adulto , Anciano , Quimioembolización Terapéutica/efectos adversos , Análisis Costo-Beneficio , Femenino , Costos de la Atención en Salud , Humanos , Isoxazoles/administración & dosificación , Isoxazoles/efectos adversos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Náusea y Vómito Posoperatorios/prevención & control , Sufentanilo/administración & dosificación , Sufentanilo/efectos adversos
11.
Water Res ; 139: 372-380, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29665509

RESUMEN

The present study proposed and demonstrated a novel process for the bioconversion of syngas (mainly CO and H2) to valuable volatile fatty acids (VFA) by integrating with mesophilic alkaline fermentation of waste activated sludge (WAS). The results showed that although pH 9 was suitable for VFA production from WAS, 62.5% of the consumed CO was converted to methane due to the presence of hydrogenogenic pathway for CO conversion. The increase of pH from 9 to 9.5 inhibited the methane production from CO because of the possible presence of only acetogenic pathway for CO conversion. However, methane was still produced from H2 contained in syngas through hydrogenotrophic methanogenesis, and around 32-34% of the consumed syngas was converted to methane. At both pH 9 and 9.5, methane was produced by hydrogenotrophic methanogens Methanobacteriales. Further increase of pH to 10 effectively inhibited methane production from syngas, and efficient VFA (mainly acetate with the concentration of around 135 mM) production by simultaneous conversion of syngas and WAS was achieved. High acetate concentrations (>150 mM) were shown to have serious negative effects on the conversion of syngas. The addition of syngas to the mesophilic alkaline fermentation of WAS at pH 10 not only resulted in the enrichment of some known bacteria related with syngas conversion, but also changed the microbial community compositions for the fermentation of WAS.


Asunto(s)
Ácidos Grasos Volátiles/metabolismo , Metano/metabolismo , Aguas del Alcantarillado , Bacterias/metabolismo , Reactores Biológicos , Monóxido de Carbono/metabolismo , Fermentación , Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno
12.
Appl Environ Microbiol ; 84(6)2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29330191

RESUMEN

Thermophilic alkaline fermentation followed by mesophilic anaerobic digestion (TM) for hydrogen and methane production from waste-activated sludge (WAS) was investigated. The TM process was also compared to a process with mesophilic alkaline fermentation followed by a mesophilic anaerobic digestion (MM) and one-stage mesophilic anaerobic digestion (M) process. The results showed that both hydrogen yield (74.5 ml H2/g volatile solids [VS]) and methane yield (150.7 ml CH4/g VS) in the TM process were higher than those (6.7 ml H2/g VS and 127.8 ml CH4/g VS, respectively) in the MM process. The lowest methane yield (101.2 ml CH4/g VS) was obtained with the M process. Taxonomic results obtained from metagenomic analysis showed that different microbial community compositions were established in the hydrogen reactors of the TM and MM processes, which also significantly changed the microbial community compositions in the following methane reactors compared to that with the M process. The dynamics of bacterial pathogens were also evaluated. For the TM process, the reduced diversity and total abundance of bacterial pathogens in WAS were observed in the hydrogen reactor and were further reduced in the methane reactor, as revealed by metagenomic analysis. The results also showed not all bacterial pathogens were reduced in the reactors. For example, Collinsella aerofaciens was enriched in the hydrogen reactor, which was also confirmed by quantitative PCR (qPCR) analysis. The study further showed that qPCR was more sensitive for detecting bacterial pathogens than metagenomic analysis. Although there were some differences in the relative abundances of bacterial pathogens calculated by metagenomic and qPCR approaches, both approaches demonstrated that the TM process was more efficient for the removal of bacterial pathogens than the MM and M processes.IMPORTANCE This study developed an efficient process for bioenergy (H2 and CH4) production from WAS and elucidates the dynamics of bacterial pathogens in the process, which is important for the utilization and safe application of WAS. The study also made an attempt to combine metagenomic and qPCR analyses to reveal the dynamics of bacterial pathogens in anaerobic processes, which could overcome the limitations of each method and provide new insights regarding bacterial pathogens in environmental samples.


Asunto(s)
Bacterias/aislamiento & purificación , Hidrógeno/metabolismo , Metano/metabolismo , Aguas del Alcantarillado/microbiología , Anaerobiosis , Bacterias/genética , Fermentación , Calor , Concentración de Iones de Hidrógeno , Metagenómica , Reacción en Cadena en Tiempo Real de la Polimerasa
13.
Biotechnol Biofuels ; 10: 140, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28580014

RESUMEN

BACKGROUND: Hydrothermal liquefaction (HTL) has been well studied for the bio-oil production from biomass. However, a large amount of wastewater with high organic content is also produced during the HTL process. Therefore, the present study investigated the methane potentials of hydrothermal liquefaction wastewater (HTLWW) obtained from HTL of rice straw at different temperatures (170-320 °C) and residence times (0.5-4 h). The characteristics (e.g., total organic content, organic species, molecular size distribution, etc.) of the HTLWW were studied, and at the same time, microbial community compositions involved in AD of HTLWW were analyzed. RESULTS: The highest methane yield of 314 mL CH4/g COD was obtained from the sample 200 °C-0.5 h (HTL temperature at 200 °C for 0.5 h), while the lowest methane yield 217 mL CH4/g COD was obtained from the sample 320 °C-0.5 h. These results were consistent with the higher amounts of hard biodegradable organics (furans, phenols, etc.) and lower amounts of easily biodegradable organics (sugars and volatile fatty acids) present in sample 320 °C-0.5 h compared to sample 200 °C-0.5 h. Size distribution analysis showed that sample 320 °C-0.5 h contained more organics with molecular size less than 1 kDa (79.5%) compared to sample 200 °C-0.5 h (66.2%). Further studies showed that hard biodegradable organics were present in the organics with molecular size higher than 1 kDa for sample 200 °C-0.5 h. In contrast, those organics were present in both the organics with molecular size higher and less than 1 kDa for sample 320 °C-0.5 h. Microbial community analysis showed that different microbial community compositions were established during the AD with different HTLWW samples due to the different organic compositions. For instance, Petrimonas, which could degrade sugars, had higher abundance in the AD of sample 200 °C-0.5 h (20%) compared to sample 320 °C-0.5 h (7%). The higher abundance of Petrimonas was consistent with the higher content of sugars in sample 200 °C-0.5 h. The higher Petrimonas abundance was consistent with the higher content of sugars in sample 200 °C-0.5 h. The genus Syntrophorhabdus could degrade phenols and its enrichment in the AD of sample 320 °C-0.5 h might be related with the highest content of phenols in the HTLWW. CONCLUSIONS: HTL parameters like temperature and residence time affected the biodegradability of HTLWW obtained from HTL of rice straw. More hard biodegradable organics were produced with the increase of HTL temperature. The microbial community compositions during the AD were also affected by the different organic compositions in HTLWW samples.

14.
Small ; 11(2): 239-47, 2015 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24925046

RESUMEN

The transdermal administration of chemotherapeutic agents is a persistent challenge for tumor treatments. A model anticancer agent, epirubicin (EPI), is attached to functionalized superparamagnetic iron-oxide nanoparticles (SPION). The covalent modification of the SPION results in EPI-SPION, a potential drug delivery vector that uses magnetism for the targeted transdermal chemotherapy of skin tumors. The spherical EPI-SPION composite exhibits excellent magnetic responsiveness with a saturation magnetization intensity of 77.8 emu g(-1) . They feature specific pH-sensitive drug release, targeting the acidic microenvironment typical in common tumor tissues or endosomes/lysosomes. Cellular uptake studies using human keratinocyte HaCaT cells and melanoma WM266 cells demonstrate that SPION have good biocompatibility. After conjugation with EPI, the nanoparticles can inhibit WM266 cell proliferation; its inhibitory effect on tumor proliferation is determined to be dose-dependent. In vitro transdermal studies demonstrate that the EPI-SPION composites can penetrate deep inside the skin driven by an external magnetic field. The magnetic-field-assisted SPION transdermal vector can circumvent the stratum corneum via follicular pathways. The study indicates the potential of a SPION-based vector for feasible transdermal therapy of skin cancer.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Epirrubicina/administración & dosificación , Compuestos Férricos/administración & dosificación , Nanopartículas del Metal , Neoplasias/tratamiento farmacológico , Piel/metabolismo , Materiales Biocompatibles , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Neoplasias/patología , Microambiente Tumoral
15.
Physiol Plant ; 152(2): 367-79, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24641584

RESUMEN

Xylan is the major hemicellulosic constituent in dicot secondary cell walls. Cell wall composition of cotton fiber changes dynamically throughout development. Not only the amounts but also the molecular sizes of the hemicellulosic polysaccharides show substantial changes during cotton fiber development. However, none of the genes encoding glycosyltransferases (GTs) responsible for synthesizing xylan have been isolated and characterized in cotton fiber. In this study, we applied a bioinformatics approach and identified two putative GTs from cotton, designated GhGT43A1 and GhGT43C1, which belong to the CAZy GT43 family and are closely related to Arabidopsis IRX9 and IRX14, respectively. We show that GhGT43A1 is highly and preferentially expressed in 15 and 20 days post-anthesis (dpa) cotton fiber, whereas GhGT43C1 is ubiquitously expressed in most organs, with especially high expression in 15 dpa fiber and hypocotyl. Complementation analysis demonstrates that GhG43A1 and GhGT43C1 are orthologs of Arabidopsis IRX9 and IRX14, respectively. Furthermore, we show that overexpression of GhGT43A1 or GhGT43C1 in Arabidopsis results in increased xylan content. We also show that overexpression of GhGT43A1 or GhGT43C1 leads to more cellulose deposition. These findings suggest that GhGT43A1 and GhGT43C1 likely participate in xylan synthesis during fiber development.


Asunto(s)
Fibra de Algodón , Glicosiltransferasas/metabolismo , Gossypium/enzimología , Gossypium/crecimiento & desarrollo , Desarrollo de la Planta , Polisacáridos/biosíntesis , Xilanos/biosíntesis , Arabidopsis/enzimología , Pared Celular/metabolismo , Celulosa/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Glicosiltransferasas/aislamiento & purificación , Gossypium/genética , Monosacáridos/análisis , Mutación/genética , Pectinas/metabolismo , Fenotipo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tallos de la Planta/anatomía & histología
16.
PLoS One ; 8(3): e59115, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23527103

RESUMEN

Arabinogalactan proteins (AGPs), are a group of highly glycosylated proteins that are found throughout the plant kingdom. To date, glycosyltransferases that glycosylate AGP backbone have remained largely unknown. In this study, a gene (GhGalT1) encoding a putative ß-1,3-galactosyltransferase (GalT) was identified in cotton. GhGalT1, belonging to CAZy GT31 family, is the type II membrane protein that contains an N-terminal transmembrane domain and a C-terminal galactosyltransferase functional domain. A subcellular localization assay demonstrated that GhGalT1 was localized in the Golgi apparatus. RT-PCR analysis revealed that GhGalT1 was expressed at relatively high levels in hypocotyls, roots, fibers and ovules. Overexpression of GhGalT1 in Arabidopsis promoted plant growth and metabolism. The transgenic seedlings had much longer primary roots, higher chlorophyll content, higher photosynthetic efficiency, the increased biomass, and the enhanced tolerance to exogenous D-arabinose and D-galactose. In addition, gas chromatography (GC) analysis of monosaccharide composition of cell wall fractions showed that pectin was changed in the transgenic plants, compared with that of wild type. Three genes (GAUT8, GAUT9 and xgd1) involved in pectin biosynthesis were dramatically up-regulated in the transgenic lines. These data suggested that GhGalT1 may be involved in regulation of pectin biosynthesis required for plant development.


Asunto(s)
Pared Celular/metabolismo , Galactosiltransferasas/genética , Galactosiltransferasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Gossypium/genética , Gossypium/metabolismo , Pectinas/biosíntesis , Adaptación Biológica/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Arabinosa/metabolismo , Galactosa/metabolismo , Galactosiltransferasas/química , Espacio Intracelular , Datos de Secuencia Molecular , Especificidad de Órganos/genética , Filogenia , Plantas Modificadas Genéticamente , Transporte de Proteínas , Plantones/genética , Plantones/crecimiento & desarrollo , Alineación de Secuencia
17.
Zhongguo Zhong Yao Za Zhi ; 32(5): 393-6, 2007 Mar.
Artículo en Chino | MEDLINE | ID: mdl-17511142

RESUMEN

OBJECTIVE: To investigate the effect of different permeation enhancer on transdermal permeation of anemonin through human skin. METHOD: The permeation experiments were performed using human skin on modified Franz diffusion cells in vitro. The concentrations of anemonin in receptor compartment at specified time points were determined by HPLC. The steady flux and the cumulative quantity of anemonin through skin were calculated. RESULT: The flux of anemonin permeating through human skin from 30% ethanol, 50% ethanol solution and a combination of 3% laurocapm -5% polysorbate 20 and 30% ethanol -3 % laurocapm -5% polysorbate 20 of anemonin was (9.30 +/- 0.32), (18.56+/-0.58), (7.29+/-0.35), (13.77+/-0. 16) microg x cm(-2) x h(-1) and 7.9, 15.9, 6.2, 11.8 times higher than from saturated water solution respectively. CONCLUSION: Ethanol and laurocapm can remarkably improve the transdermal permeation of anemonin and the anemonin have the potential to be developed to new transdermal preparation.


Asunto(s)
Azepinas/farmacología , Etanol/farmacología , Furanos/farmacocinética , Piel/efectos de los fármacos , Administración Cutánea , Clematis/química , Furanos/administración & dosificación , Furanos/aislamiento & purificación , Humanos , Técnicas In Vitro , Permeabilidad/efectos de los fármacos , Plantas Medicinales/química , Piel/metabolismo , Absorción Cutánea/efectos de los fármacos
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