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1.
Nat Mater ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514845

RESUMEN

Artificial pressure sensors often use soft materials to achieve skin-like softness, but the viscoelastic creep of soft materials and the ion leakage, specifically for ionic conductors, cause signal drift and inaccurate measurement. Here we report drift-free iontronic sensing by designing and copolymerizing a leakage-free and creep-free polyelectrolyte elastomer containing two types of segments: charged segments having fixed cations to prevent ion leakage and neutral slippery segments with a high crosslink density for low creep. We show that an iontronic sensor using the polyelectrolyte elastomer barely drifts under an ultrahigh static pressure of 500 kPa (close to its Young's modulus), exhibits a drift rate two to three orders of magnitude lower than that of the sensors adopting conventional ionic conductors and enables steady and accurate control for robotic manipulation. Such drift-free iontronic sensing represents a step towards highly accurate sensing in robotics and beyond.

2.
Molecules ; 29(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38792130

RESUMEN

Lycium ruthenicum Murray possesses significant applications in both food and medicine, including antioxidative, anti-tumor, anti-fatigue, anti-inflammatory, and various other effects. Consequently, there has been a surge in research endeavors dedicated to exploring its potential benefits, necessitating the organization and synthesis of these findings. This article systematically reviews the extraction and content determination methods of active substances such as polysaccharides, anthocyanins, flavonoids, and polyphenols in LRM in the past five years, as well as some active ingredient composition determination methods, biological activities, and product development. This review is divided into three main parts: extraction and determination methods, their bioactivity, and product development. Building upon prior research, we also delve into the economic and medicinal value of Lycium ruthenicum Murray, thereby contributing significantly to its further exploration and development. It is anticipated that this comprehensive review will serve as a valuable resource for advancing research on Lycium ruthenicum Murray.


Asunto(s)
Lycium , Extractos Vegetales , Lycium/química , Extractos Vegetales/química , Antocianinas/química , Humanos , Flavonoides/química , Antioxidantes/química , Antioxidantes/farmacología , Polifenoles/química , Fitoquímicos/química , Fitoquímicos/farmacología , Polisacáridos/química
3.
Soft Matter ; 19(14): 2570-2578, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36946098

RESUMEN

Eutectogels are stretchable ionic conductors extensively developed in recent years, owing to their distinct advantages of low cost, non-volatility, non-toxicity, and outstanding biocompatibility. However, the susceptibility to humidity caused by the exchange of water molecules between the interiors of eutectogels and the external environment greatly restricts their practical applications. Here, a dip-coating strategy is proposed to fabricate a P(MEA-co-IBA) elastomer-coated P(AAC-co-AAM) eutectogel to achieve satisfactory humidity-resistant capability. The hydrophobic elastomer coating significantly suppresses water exchange without harming the stretchability (>500%) and conductivity of the eutectogel. Strong adhesion forms at the eutectogel-coating interface due to the formation of an interpenetrating layer. The superior electromechanical performances of encapsulated eutectogels enable stretchable ionotronic devices with stable electrical performance (>1 h) and remarkable water-droplet/moist resistances during static/dynamic loadings. A humidity-resistant encapsulated eutectogel-based wearable strain sensor is further demonstrated. The proposed humidity-resistant eutectogels are promising candidates for soft and wearable ionotronics for practical applications.

4.
Macromol Rapid Commun ; 44(12): e2200957, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36950905

RESUMEN

The emergence of hydrophobic ionogels composed of hydrophobic polymer matrices and hydrophobic ionic liquids has drastically broadened the applications of ionic devices, especially for underwater explorations. Compared with traditional ionogels, hydrophobic ones are capable of achieving long-term stability in ambient and aqueous environments. In this review, the latest research developments of intrinsically hydrophobic ionogels are summarized, with particular emphases placed on the materials, mechanisms and applications. The basic issues about hydrophobic ionogels, including the material systems, dynamic gelation bonds and network structures are elucidated. The up-to-date advent of the ambient/underwater applications of hydrophobic ionogels concerning adhesion, self-healing, and sensing are comprehensively summarized. Special attention is paid to underwater scenarios considering the rapid development of marine explorations and the intrinsic properties of hydrophobic ionogels. Finally, the current challenges and immediate opportunities of this emerging yet fast-developing research field are discussed.


Asunto(s)
Líquidos Iónicos , Geles/química , Líquidos Iónicos/química , Agua , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros
5.
Pain Pract ; 23(7): 743-758, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37183316

RESUMEN

OBJECTIVE: We explored the feasibility of single-division puncture in the ophthalmic division, maxillary division, and mandibular division of the trigeminal ganglion intumescentia (TGI) and the feasibility of radiofrequency treatment of trigeminal neuralgia. METHODS: According to the previous anatomical image studies, 3D Slicer software was used to analyze the CT images of the patients. The trigeminal ganglion fossa (TGF) was used as the imaging sign. TGI was identified in the sagittal plane along the fiber. The puncture path starts from the TGI center-foramen ovale line, extending outward to the epidermis as the needle insertion point, and extending inward to the division boundary. For lateral puncture, which is blocked by the mandible, the positions of closed mouth, open mouth, and over-open mouth were used. Multiple targets were generated using straight electrodes and curved electrodes to achieve full coverage of TGI. According to the preoperative design, general anesthesia surgery was performed. Xper CT was used for imaging, and the puncture was guided by Xper Guide. Radiofrequency treatment of TGI was conducted. RESULTS: In total, 45 patients with trigeminal neuralgia underwent 50 single-division TGI punctures. The procedure was smooth and the compliance with the design was good. Continuous radiofrequency (CRF) was performed, the VAS scores were 25 times at 70°C, 19 times at 65°C, two times at 60°C, and two times at 50°C (both in the ophthalmic division). Pulsed radiofrequency (PRF) was conducted two times. Within 24 h after the procedure, the VAS scores were all 0. From 1 to 7 days after the procedure, pain recurrence was found in three cases, of whom two cases received pulsed radiofrequency treatment. Patients were followed up for 1-24 months and there were no recurrence. After continuous radiofrequency at 65-70°C, the moderate tactile loss was observed, and nearly half of the patients had food residues on the surgical side after 6 months. After continuous radiofrequency at 60°C, there was mild tactile loss and no food residue. The tactile sensation was slightly decreased after continuous radiofrequency at 50°C, and the tactile sensation was normal the next day. CONCLUSION: Trigeminal ganglion intumescentia single-division radiofrequency is effective and feasible for the treatment of trigeminal neuralgia.


Asunto(s)
Tratamiento de Radiofrecuencia Pulsada , Neuralgia del Trigémino , Humanos , Ganglio del Trigémino/diagnóstico por imagen , Ganglio del Trigémino/cirugía , Neuralgia del Trigémino/diagnóstico por imagen , Neuralgia del Trigémino/cirugía , Tratamiento de Radiofrecuencia Pulsada/métodos , Punciones , Manejo del Dolor/métodos , Electrocoagulación/métodos , Resultado del Tratamiento
6.
Soft Matter ; 18(2): 272-281, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34889348

RESUMEN

In this work, the peel of hydrogels under a stiff backing constraint was studied using a finite element method. The finite element method was first validated by comparing the simulation results to theoretical predictions and experimental measurements. Then, the method was used to investigate the effects of adhesion thickness, adhesion length and backing thickness on the peel behaviors, as well as the stress distribution within the adhesion layer. The results indicated that the peel force-displacement curve has a constant profile when the adhesion thickness and backing thickness are prescribed so long as the adhesion length is sufficiently long. The peak peel force increases with the adhesion length and then plateaus. The larger the intrinsic peak stress or the thicker the backing, the higher the plateau. The steady-state peel force is independent of the backing thickness, while positively correlated with the strain energy storage of the hydrogel adhesion layer. The critical vertical displacement corresponding to the peak peel force increases with the hydrogel thickness and decreases with the backing thickness. However, the critical vertical displacement corresponding to the steady-state peel force increases with the backing thickness. The present work puts forward an effective numerical approach to probe the peel of hydrogels, which is beneficial for the design of relevant structures.

7.
Environ Sci Technol ; 56(8): 4795-4805, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35235293

RESUMEN

Isoprene is the most abundant precursor of global secondary organic aerosol (SOA). The epoxide pathway plays a critical role in isoprene SOA (iSOA) formation, in which isoprene epoxydiols (IEPOX) and/or hydroxymethyl-methyl-α-lactone (HMML) can react with nucleophilic sulfate and water producing isoprene-derived organosulfates (iOSs) and oxygen-containing tracers (iOTs), respectively. This process is complicated and highly influenced by anthropogenic emissions, especially in the polluted urban atmospheres. In this study, we took a 1-year measurement of the paired iOSs and iOTs formed through the IEPOX and HMML pathways at the three urban sites from northern to southern China. The annual average concentrations of iSOA products at the three sites ranged from 14.6 to 36.5 ng m-3. We found that the nucleophilic-addition reaction of isoprene epoxides with water dominated over that with sulfate in the polluted urban air. A simple set of reaction rate constant could not fully describe iOS and iOT formation everywhere. We also found that the IEPOX pathway was dominant over the HMML pathway over urban regions. Using the kinetic data of IEPOX to estimate the reaction parameters of HMML will cause significant underestimation in the importance of HMML pathway. All these findings provide insights into iSOA formation over polluted areas.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Epoxi , Aerosoles/análisis , Butadienos , Hemiterpenos , Pentanos , Sulfatos , Agua
8.
Ecotoxicol Environ Saf ; 238: 113575, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35500402

RESUMEN

Sogatella furcifera is one of the main agricultural pests in many Asian countries, bringing about enormous injury. A triflumezopyrim-resistant (Tri) strain of S. furcifera was established through continuous screening in laboratory. The determination of synergist and enzyme activity indicated that P450s, especially for the upregulation expression of CYPSF01, played a key role in the increased resistance, confirmed by RNAi, and the recombinant protein of CYPSF01 and NADPH-P450 reductase was able to degrade triflumezopyrim. CYPSF01 had an obviously co-expression relationship with nuclear receptor ultraspiracle (USP), which were all significantly up-regulated when exposed to triflumezopyrim. Further, a USP-binding motif MA0534.1 was enriched from the upregulated peaks by Assay for Transposase Accessible Chromatin (ATAC-seq) analysis, which exited in the peaks located on the promoter of CYPSF01; the yeast one-hybrid experiments confirmed that USP could bind to the CYPSF01 promoter. And the USP interference significantly down-regulated CYPSF01 expression, and resulted in the significantly increasing sensitivity to triflumezopyrim, its mortality rate increased 28.37%. Therefore, the overexpression of USP could cause to the overexpression of CYPSF01, ultimately resulting in the resistance to triflumezopyrim in S. furcifera.


Asunto(s)
Hemípteros , Insecticidas , Animales , Hemípteros/metabolismo , Insecticidas/metabolismo , Piridinas/metabolismo , Pirimidinonas , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo
9.
Ecotoxicol Environ Saf ; 234: 113425, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35325711

RESUMEN

Spodoptera litura is a widely distributed multifeeding pest, that has developed high resistance to many chemical insecticides. In the present study, a bistrifluron-resistant (Bis-SEL) strain showing 113.8-fold resistance ratio relative to a bistrifluron-susceptible (Bis-UNSEL) strain was obtained and showed a fitness advantage (resurgence). First, we found that the observed resurgence might have resulted from Maf transcription factor overexpression in the Bis-SEL strain, which would influence the synthesis of ecdysone and chitin. Additionally, a co-expression relationship between Maf and CYP307A1 was verified by weighted correlation network analysis (WGCNA) and qRT-PCR, and the expression of CYP307A1, a key gene in ecdysone synthesis, was significantly downregulated by Maf interference. The assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and a yeast one-hybrid showed that Maf could bind to the cncc:maf-s element in the CYP307A1 promoter region. The synthesis of ecdysone, which stimulated chitin synthesis, was also decreased significantly following Maf and CYP307A1 interference. Therefore, the upregulation of Maf expression leaded to the upregulation CYP307A1 expression, which led to an increase in the synthesis of ecdysone, resulting in resurgence accompanied by resistance to bistrifluron.

10.
Int J Mol Sci ; 23(22)2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36430247

RESUMEN

Long-term pesticide-driven selection pressure is one of the main causes of insect outbreaks. In this study, we found that low doses of triflumezopyrim could increase the fecundity of white-backed planthoppers (Sogatella furcifera). By continuously screening 20 generations with a low dose of triflumezopyrim, a triflumezopyrim-resistant strain (Tri-strain, resistance ratio = 20.9-fold) was obtained. The average oviposition quantity and longevity of the Tri-strain (208.77 eggs and 21.31 days, respectively) were significantly higher than those of the susceptible strain (Sus-strain) (164.62 eggs and 17.85 days, respectively). To better understand the mechanism underlying the effects on reproduction, we detected the expression levels of several reproduction-related transcription factors in both the Tri- and Sus-strains. Ultraspiracle (USP) was significantly overexpressed in the Tri-strain. Knockdown of USP by RNAi severely inhibited the moulting process of S. furcifera and disrupted the development of female adult ovaries. Among the potential downstream target genes of USP, Kr-h1 (0.19-fold), Cht8 (0.56-fold) and GPCR A22 (0.31-fold) showed downregulated expression after USP-RNAi. In contrast, the expression of EcR (2.55-fold), which forms heterodimers with USP, was significantly upregulated. Furthermore, RNAi was performed on Kr-h1 in the Tri-strain, and the results show that larval moulting and the development of female adult ovaries were inhibited, consistent with the USP-RNAi results in S. furcifera. These results suggest that the transcription factors USP and Kr-h1 play important roles in the reproductive development of S. furcifera, and overexpression of USP and Kr-h1 in the Tri-resistant strain may result in reproductive outbreaks of pests.


Asunto(s)
Hemípteros , Reproducción , Femenino , Animales , Receptores Citoplasmáticos y Nucleares , Brotes de Enfermedades , Factores de Transcripción/genética
11.
Psychol Res ; 85(4): 1645-1661, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32448946

RESUMEN

The SNARC (Spatial-Numerical Association of Response Codes) effect (i.e., a tendency to associate small/large magnitude numbers with the left/right hand side) is prevalent across the whole lifespan. Because the ability to relate numbers to space has been viewed as a cornerstone in the development of mathematical skills, the relationship between the SNARC effect and math skills has been frequently examined. The results remain largely inconsistent. Studies testing groups of people with very low or very high skill levels in math sometimes found relationships between SNARC and math skills. So far, however, studies testing such extreme math skills level groups were mostly investigating the SNARC effect in individuals revealing math difficulties. Groups with above average math skills remain understudied, especially in regard to children. Here, we investigate the SNARC effect in gifted children, as compared to normally developing children (overall n = 165). Frequentist and Bayesian analysis suggested that the groups did not differ from each other in the SNARC effect. These results are the first to provide evidence for the SNARC effect in a relatively large sample of gifted (and mathematically highly skilled) children. In sum, our study provides another piece of evidence for no direct link between the SNARC effect and mathematical ability in childhood.


Asunto(s)
Aptitud , Niño Superdotado , Cognición/fisiología , Tiempo de Reacción/fisiología , Percepción Espacial/fisiología , Teorema de Bayes , Estudios de Casos y Controles , Niño , Humanos , Masculino , Matemática
12.
Mikrochim Acta ; 186(6): 360, 2019 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-31098844

RESUMEN

Cobalt oxyhydroxide (CoOOH) was grown on the surface of graphitic-phase C3N4 nanosheets to obtain an activatable fluorescent nanoprobe for ascorbic acid (AA). The probe was applied to the detection of AA in biological fluids and to image AA in HeLa cells. The negatively charged nanosheets first adsorb Co2+, and then the CoOOH nanoflakes are generated in-situ on the surface of g-C3N4. This results in the quenching of the blue fluorescence (with excitation/emission maxima of 345/435 nm) via fluorescence resonance energy transfer from g-C3N4 to CoOOH. The AA-induced redox reaction reduces the trivalent cobalt ion in CoOOH to Co2+ which then becomes released from the nanosheets. This leads to the recovery of fluorescence. The method can quantify AA in the 1.0 to 800 µM concentration range at near neutral pH values. When applied to cell extracts, the limit of detection is 0.14 µM. The nanoprobe was successfully applied to the determination of AA in serum and urine, and to image AA in living HeLa cells. Additional attractive features include the ease of preparation, low cytotoxicity, rapid fluorometric turn-on response, and good biocompatibility. Graphical abstract Schematic presentation of an activatable fluorescent nanoprobe. It consists of CoOOH nanoflakes that were modified withg-C3N4 nanosheets. It enables monitoring of AA in the biological samples as well as imaging of AA in living cells.


Asunto(s)
Ácido Ascórbico/análisis , Colorantes Fluorescentes/química , Carbono/química , Supervivencia Celular , Cobalto/química , Fluorescencia , Grafito/química , Células HeLa , Humanos , Hidróxidos/química , Nanopartículas/química , Nitrógeno/química , Imagen Óptica , Oxígeno/química , Células Tumorales Cultivadas
13.
J Xray Sci Technol ; 26(1): 125-131, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29480234

RESUMEN

BACKGROUND: Congenital hydronephrosis is often caused by aberrant renal vessel and it is difficult to be diagnosed and treated at the early stage due to lack of the significant symptoms. Although current medical diagnosis tools are widely used, the aberrant renal vessel cannot be displayed very well in the images. OBJECTIVE: To investigate whether applying computed tomography (CT) angiography with 3D reconstruction can improve efficacy in diagnose of this congenital hydronephrosis. MATERIALS AND METHODS: A male patient of 18 years old was diagnosed as hydronephrosis of left kidney. A CT angiography with 3D reconstruction was evaluated in diagnosis of the prenatal hydronephrosis compared to ultrasound (US) and intravenous urogram (IVU). RESULTS: US and IVU images were able to display the dilation of left pelvic and the dilated calyces, and the thinner of renal parenchyma on the left kidney (Grade II-IV), but failed to detect the causing of hydro-nephrosis. CT angiography with 3D reconstruction provided accurate images of the dilated renal pelvic, upper segment of the ureter, and an aberrant vessel bundle overcrossing at the left renal pelvic-ureter junction as well. The aberrant vessel could be revealed during surgery. CONCLUSIONS: A CT angiography with 3D reconstruction provides a more accurate diagnostic approach for the congenital hydronephrosis caused by aberrant renal vessel. Thus, it can offer surgeons very important information in the pre-surgery planning.


Asunto(s)
Angiografía por Tomografía Computarizada , Hidronefrosis/diagnóstico por imagen , Imagenología Tridimensional , Adolescente , Humanos , Riñón/irrigación sanguínea , Riñón/diagnóstico por imagen , Masculino
14.
Prostate ; 77(3): 274-281, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27718273

RESUMEN

BACKGROUND: Currently, the role of UPR signaling in prostate cancer (PCa) is unclear. To evaluate the relationship between UPR signaling pathway and the prognosis of PCa, we explored the expression of IRE1, PERK, and ATF6 in tissues. METHODS: A total of 160 PCa and 30 benign prostate hyperplasia (BPH) tissues were collected. The expression of UPR signaling factors was assessed by immunohistochemistry. The staining characteristics were identified and evaluated for associations with clinicopathologic parameters, PSA recurrence survival, and prostate cancer-specific morality. RESULTS: The expressions of ATF6α, PERK, and IRE1α were significantly associated with Gleason grade, PSA level, T stages and M stage, while this association was not significant in N stage. Additionally, UPR signaling factors expressed correlatively with each other. In further studies, high expression level of UPR signaling factors was usually detected in patients who suffered poor prognosis. Patients with positive UPR signaling factors meet shorter survival duration both on cancer-specific morality and PSA recurrence. Multivariate analysis showed that IRE1α (HR = 4.461 95%CI = 1.270-15.670 P = 0.020) could be a potential factor in predicting PSA recurrence independently. CONCLUSIONS: UPR signaling factors were co-activated and activation of UPR signaling was implicated to the malignant progression and worse prognosis of PCa. The mechanism and function of UPR signaling in PCa are still to be determined. Prostate 77:274-281, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Progresión de la Enfermedad , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/metabolismo , Transducción de Señal/fisiología , Respuesta de Proteína Desplegada/fisiología , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Hiperplasia Prostática/patología , Neoplasias de la Próstata/patología , Estudios Retrospectivos
15.
Metab Brain Dis ; 32(2): 565-575, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28064406

RESUMEN

Vps4, vacuolar protein sorting 4, belongs to ATPases Associated with diverse cellular Activities (AAA) protein family which is made up of Vps4A and Vps4B. Previous studies demonstrated that Vps4A plays vital roles in diverse aspects such as virus budding, the efficient transport of H-Ras to the PM (plasma membrane) and the involvement in the MVB (multivesiculate bodies) pathway. Interestingly, Vps4A is also expressed in the brain. However, the distribution and function of Vps4A in ICH diseases remain unclear. In this study, we show that Vps4A may be involved in neuronal apoptosis during pathophysiological processes of intracerebral hemorrhage (ICH). Based on the results of Western blot and immunohistochemistry, we found a remarkable up-regulation of Vps4A expression surrounding the hematoma after ICH. Double labeled immunofluorescence showed that Vps4A was co-expressed with NeuN but rarely with astrocytes and microglia. Morever, we detected that neuronal apoptosis marker active caspase-3 had co-localizations with Vps4A. Additionaly, Vps4A knockdown in vitro specifically leads to decreasing neuronal apoptosis coupled with increased Akt phosphorylation. All datas suggested that Vps4A was involved in promoting neuronal apoptosis via inhibiting Akt phosphorylation after ICH.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas/biosíntesis , Apoptosis/efectos de los fármacos , Hemorragia Cerebral/metabolismo , ATPasas de Translocación de Protón Vacuolares/biosíntesis , Animales , Antígenos Nucleares/metabolismo , Conducta Animal/efectos de los fármacos , Caspasa 3/metabolismo , Hemorragia Cerebral/patología , Hemorragia Cerebral/psicología , Femenino , Técnicas de Silenciamiento del Gen , Masculino , Proteínas del Tejido Nervioso/metabolismo , Proteína Oncogénica v-akt/metabolismo , Fosforilación , Embarazo , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba/efectos de los fármacos
16.
Proc Natl Acad Sci U S A ; 111(12): 4495-500, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24616523

RESUMEN

The process of nitrite-dependent anaerobic methane oxidation (n-damo) was recently discovered and shown to be mediated by "Candidatus Methylomirabilis oxyfera" (M. oxyfera). Here, evidence for n-damo in three different freshwater wetlands located in southeastern China was obtained using stable isotope measurements, quantitative PCR assays, and 16S rRNA and particulate methane monooxygenase gene clone library analyses. Stable isotope experiments confirmed the occurrence of n-damo in the examined wetlands, and the potential n-damo rates ranged from 0.31 to 5.43 nmol CO2 per gram of dry soil per day at different depths of soil cores. A combined analysis of 16S rRNA and particulate methane monooxygenase genes demonstrated that M. oxyfera-like bacteria were mainly present in the deep soil with a maximum abundance of 3.2 × 10(7) gene copies per gram of dry soil. It is estimated that ∼0.51 g of CH4 m(-2) per year could be linked to the n-damo process in the examined wetlands based on the measured potential n-damo rates. This study presents previously unidentified confirmation that the n-damo process is a previously overlooked microbial methane sink in wetlands, and n-damo has the potential to be a globally important methane sink due to increasing nitrogen pollution.


Asunto(s)
Anaerobiosis , Bacterias/metabolismo , Metano/metabolismo , Humedales , Bacterias/clasificación , Bacterias/genética , Genes Bacterianos , Datos de Secuencia Molecular , Oxidación-Reducción , Filogenia , ARN Ribosómico 16S/genética
17.
Appl Microbiol Biotechnol ; 99(1): 349-57, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25242345

RESUMEN

Nitrite-dependent anaerobic methane oxidation (n-damo) is a recently discovered process that is catalysed by "Candidatus Methylomirabilis oxyfera". In the present study, the vertical distribution (0-10, 20-30, 50-60 and 90-100 cm) of M. oxyfera-like bacteria was investigated in Xiazhuhu wetland, the largest natural wetland on the southern Yangtze River (China). Phylogenetic analyses showed that group A of M. oxyfera-like bacteria and pmoA genes occurred primarily at depths of 50-60 and 90-100 cm. Quantitative PCR further confirmed the presence of M. oxyfera-like bacteria in soil cores from different depths, with the highest abundance of 5.1 × 10(7) copies g(-1) dry soil at depth of 50-60 cm. Stable isotope experiments demonstrated that the n-damo process occurred primarily at depths of 50-60 and 90-100 cm, with the potential rates ranging from 0.2 to 14.5 nmol CO2 g(-1) dry soil d(-1). It was estimated that the methane flux may increase by approximately 2.7-4.3% in the examined wetland in the absence of n-damo. This study shows that the deep wetland soils (50-60 and 90-100 cm) are the preferred habitats for M. oxyfera-like bacteria. The study also highlights the potential importance of these bacteria in the methane and nitrogen cycles in deep wetland soils.


Asunto(s)
Bacterias/clasificación , Bacterias/metabolismo , Biota , Metano/metabolismo , Nitritos/metabolismo , Microbiología del Suelo , Anaerobiosis , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Agua Dulce , Marcaje Isotópico , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Humedales
18.
J Environ Sci (China) ; 38: 14-23, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26702964

RESUMEN

Ammonia (NH3) volatilization is a major pathway of nitrogen (N) loss from soil-crop systems. As vegetable cultivation is one of the most important agricultural land uses worldwide, a deeper understanding of NH3 volatilization is necessary in vegetable production systems. We therefore conducted a 3-year (2010-2012) field experiment to characterize NH3 volatilization and evaluate the effect of different N fertilizer treatments on this process during the growth period of Chinese cabbage. Ammonia volatilization rate, rainfall, soil water content, pH, and soil NH4(+) were measured during the growth period. The results showed that NH3 volatilization was significantly and positively correlated to topsoil pH and NH4(+) concentration. Climate factors and fertilization method also significantly affected NH3 volatilization. Specifically, organic fertilizer (OF) increased NH3 volatilization by 11.77%-18.46%, compared to conventional fertilizer (CF, urea), while organic-inorganic compound fertilizer (OIF) reduced NH3 volatilization by 8.82%-12.67% compared to CF. Furthermore, slow-release fertilizers had significantly positive effects on controlling NH3 volatilization, with a 60.73%-68.80% reduction for sulfur-coated urea (SCU), a 71.85%-78.97% reduction for biological Carbon Power® urea (BCU), and a 77.66%-83.12% reduction for bulk-blend controlled-release fertilizer (BBCRF) relative to CF. This study provides much needed baseline information, which will help in fertilizer choice and management practices to reduce NH3 volatilization and encourage the development of new strategies for vegetable planting.


Asunto(s)
Amoníaco/metabolismo , Brassica/metabolismo , Nitrógeno/metabolismo , China , Fertilizantes/análisis , Suelo/química , Volatilización
19.
Gut ; 63(1): 143-51, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23300138

RESUMEN

OBJECTIVE: Tumour biomarkers are used as indicators for cancer screening and as predictors for therapeutic responses and prognoses in cancer patients. We aimed to identify genetic loci that influence concentrations of cancer antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA) and α fetoprotein (AFP), and investigated the associations between the significant single nucleotide polymorphisms (SNPs) with risks of oesophageal squamous cell (OSCC), pancreatic and hepatocellular cancers. DESIGN: We carried out a genome wide association study on plasma CA19-9, CEA and AFP concentrations in 3451 healthy Han Chinese and validated the results in 10 326 individuals. Significant SNPs were further investigated in three case control studies (2031 OSCC cases and 2044 controls; 981 pancreatic cancer cases and 1991 controls; and 348 hepatocellular cancer cases and 359 controls). RESULTS: The analyses showed association peaks on three genetic loci for CA19-9 (FUT6-FUT3 at 19p13.3, FUT2-CA11 at 19q13.3 and B3GNT3 at 19p13.1; p=1.16×10(-13)-3.30×10(-290)); four for CEA (ABO at 9q34.2, FUT6 at 19p13.3, FUT2 at 19q13.3 and FAM3B at 21q22.3; p=3.33×10(-22)-5.81×10(-209)); and two for AFP (AFP at 4q11-q13 and HISPPD2A at 15q15.3; p=3.27×10(-18) and 1.28×10(-14)). These explained 17.14% of the variations in CA19-9, 8.95% in CEA and 0.57% in AFP concentrations. Significant ABO variants were also associated with risk of OSCC and pancreatic cancers, and AFP variants with risk of hepatocellular cancer (p<0.05). CONCLUSIONS: This study identified several loci associated with CA19-9, CEA and AFP concentrations. The ABO variants were associated with risk of OSCC and pancreatic cancers and AFP variants with risk of hepatocellular cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma/genética , Neoplasias Esofágicas/genética , Estudio de Asociación del Genoma Completo , Neoplasias Hepáticas/genética , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Pueblo Asiatico , Antígeno CA-19-9/genética , Antígeno Carcinoembrionario/genética , Carcinoma/etnología , Carcinoma Hepatocelular/etnología , Carcinoma Hepatocelular/genética , Carcinoma de Células Escamosas/etnología , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , China , Neoplasias Esofágicas/etnología , Femenino , Humanos , Modelos Lineales , Neoplasias Hepáticas/etnología , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/etnología , Factores de Riesgo , alfa-Fetoproteínas/genética
20.
Genet Epidemiol ; 37(3): 293-300, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23371916

RESUMEN

Bilirubin is an effective antioxidant and is influenced by both genetic and environmental factors. Recent genome-wide association studies (GWAS) have identified multiple loci affecting serum total bilirubin levels. However, most of the studies were conducted in European populations and little attention has been devoted either to genetic variants associated with direct and indirect bilirubin levels or to the gene-environment interactions on bilirubin levels. In this study, a two-stage GWAS was performed to identify genetic variants associated with all types of bilirubin levels in 10,282 Han Chinese individuals. Gene-environment interactions were further examined. Briefly, two previously reported loci, UGT1A1 on 2q37 (rs6742078 and rs4148323, combined P = 1.44 × 10(-89) and P = 5.05 × 10(-69) , respectively) and SLCO1B3 on 12p12 (rs2417940, combined P = 6.93 × 10(-19) ) were successfully replicated. The two loci explained 9.2% and 0.9% of the total variations of total bilirubin levels, respectively. Ethnic genetic differences were observed between Chinese and European populations. More importantly, a significant interaction was found between rs2417940 in SLCO1B3 gene and smoking on total bilirubin levels (P = 1.99 × 10(-3) ). Single nucleotide polymorphism (SNP) rs2417940 had stronger effects on total bilirubin levels in nonsmokers than in smokers, suggesting that the effects of SLCO1B3 genotype on bilirubin levels were partly dependent on smoking status. Consistent associations and interactions were observed for serum direct and indirect bilirubin levels.


Asunto(s)
Bilirrubina/sangre , Bilirrubina/genética , Interacción Gen-Ambiente , Polimorfismo de Nucleótido Simple , Factores de Edad , Pueblo Asiatico/genética , Índice de Masa Corporal , Femenino , Estudio de Asociación del Genoma Completo , Glucuronosiltransferasa/genética , Humanos , Masculino , Transportadores de Anión Orgánico Sodio-Independiente/genética , Fumar/genética , Miembro 1B3 de la Familia de los Transportadores de Solutos de Aniones Orgánicos , Población Blanca/genética
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