Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38639629

RESUMO

Objective: To evaluate the effect of traditional Chinese medicine (TCM) rehabilitation on the postoperative function of patients with distal radius fractures by Meta-analysis. Methods: PubMed, Embase, CNKI, Wanfang, and other databases were searched for retrospective controlled trials and prospective randomized controlled trials on the effect of traditional Chinese medicine rehabilitation on the function of patients with distal radius fractures after surgery from the establishment of the database to May 2023. Revman version 5.3 software was used to analyze the extracted and screened index data. Results: Eight studies involving 455 patients were included. Meta-analysis results showed Overall analysis showed that there was a significant difference in wrist function between the TCM rehabilitation group and the control group (MD = -12.16, 95%CI:-17.21 to -7.11, P < .00001), low heterogeneity (I2=40%, P = .17), the difference in dorsiflexion function between the TCM rehabilitation group and the control group was statistically significant (MD = -1.16, 95%CI:-2.24 to -0.08, P = .04), with high heterogeneity (I2=79%, P = .003), that there was a significant difference in grip strength between the TCM rehabilitation group and the control group at 6 weeks (MD= 0.48, 95%CI: 0.24 to 0.71, P < .0001) with low heterogeneity (I2=45%, P = .12), there was no significant difference between the TCM rehabilitation group and the control group (OR= -0.00, 95%CI: -0.08 to 0.08, P = .99), and there was no heterogeneity (I2=0%, P = .66). Conclusion: Traditional Chinese medicine rehabilitation treatment of distal radius fractures can increase the range of motion of wrist joints, reduce pain, shorten the rehabilitation time of patients, improve the quality of life, and is conducive to the standardized treatment of patients.

2.
J Sci Food Agric ; 102(9): 3644-3654, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34888887

RESUMO

BACKGROUND: Controlled-release urea (CRU) or fulvic acid (FA), when applied, have been shown to increase nitrogen (N) use efficiency (NUE) or to stimulate plant growth, yet their interactive effects are not well explored. The objective of this study was to investigate the synergistic mechanisms of CRU combined with FA (CRU + FA) on maize (Zea mays L.) growth. Through the experimental design with five treatments, the N metabolism through the transcriptomic analysis of maize leaf, endogenous hormones, photosynthesis enzymes in maize leaf and root, and maize yield and NUE were evaluated. RESULTS: Compared with CRU treatment, CRU + FA treatment significantly increased auxin, nitrate reductase, and glutamate dehydrogenase in leaf by 35.4%, 43.9%, 40.8% and 19.5%, respectively, as well as, the relative content of the leaf chlorophyll and photosynthetic rate by 14.8% and 45.6%, respectively, at 12-leaf collar stage; the carbon/nitrogen (C/N) metabolic process was significantly enriched in CRU + FA treatment by 312 and 418 genes, according to transcriptome profiles of C/N metabolic in leaves from various fertilizer treated maize; maize yield and NUE of CRU + FA treatment were increased by 6.3% and 38.4%, respectively. CONCLUSIONS: These results demonstrated that CRU + FA is a viable fertilization scheme that can enhance maize growth, yield and NUE through their synergies in improving N uptake, promoting photosynthesis, increasing C/N metabolic processes, and enhancing enzyme activities. © 2021 Society of Chemical Industry.


Assuntos
Ureia , Zea mays , Benzopiranos , Carbono/metabolismo , Preparações de Ação Retardada/metabolismo , Fertilizantes , Nitrogênio/metabolismo , Solo/química , Ureia/metabolismo , Zea mays/metabolismo
3.
Appl Opt ; 58(31): 8404-8410, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873322

RESUMO

In this paper, we numerically investigate the mid-infrared supercontinuum (SC) generation in a suspended ${{\rm As}_2}{{\rm Se}_3}$As2Se3 ridge waveguide, which is designed with the two zero-dispersion wavelengths. Simulation results show that when the pump pulses at wavelength 3.3 µm with width of 100 fs and peak power of 900 W are launched into the anomalous dispersion region of the designed waveguide with a length of 0.87 mm, the SC can be generated in the wavelength range from 1.76 to 14.42 µm (more than three octaves), extending deep into the "fingerprint" region. The stability of the generated SC is confirmed by the first-order coherence. Moreover, we demonstrate the performance of the SC-based frequency comb by assuming a 50 pulse pump source at a repetition rate of 100 MHz.

4.
CNS Neurosci Ther ; 30(3): e14457, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37718934

RESUMO

AIMS: Electroacupuncture (EA) at the Lianquan (CV23) could alleviate swallowing dysfunction. However, current knowledge of its neural modulation focused on the brain, with little evidence from the periphery. Transient receptor potential channel vanilloid subfamily 1 (TRPV1) is an ion channel predominantly expressed in sensory neurons, and acupuncture can trigger calcium ion (Ca2+ ) wave propagation through active TRPV1 to deliver signals. The present study aimed to investigate whether TRPV1 mediated the signal of EA to the primary sensory cortex (S1) during regulation of swallowing function. METHODS: Blood perfusion was evaluated by laser speckle contrast imaging (LSCI), and neuronal activity was evaluated by fiber calcium recording and c-Fos staining. The expression of TRPV1 was detected by RNA-seq analysis, immunofluorescence, and ELISA. In addition, the swallowing function was assessed by in vivo EMG recording and water consumption test. RESULTS: EA treatment potentiated blood perfusion and neuronal activity in the S1, and this potentiation was absent after injecting lidocaine near CV23. TRPV1 near CV23 was upregulated by EA-CV23. The blood perfusion at CV23 was decreased in the TRPV1 hypofunction mice, while the blood perfusion and the neuronal activity of the S1 showed no obvious change. These findings were also present in post-stroke dysphagia (PSD) mice. CONCLUSION: The TRPV1 at CV23 after EA treatment might play a key role in mediating local blood perfusion but was not involved in transferring EA signals to the central nervous system (CNS). These findings collectively suggested that TRPV1 may be one of the important regulators involved in the mechanism of EA treatment for improving swallowing function in PSD.


Assuntos
Terapia por Acupuntura , Eletroacupuntura , Acidente Vascular Cerebral , Camundongos , Animais , Eletroacupuntura/métodos , Deglutição/fisiologia , Cálcio/metabolismo , Sistema Nervoso Central/metabolismo , Canais de Cátion TRPV/metabolismo , Pontos de Acupuntura
5.
Front Oncol ; 13: 1290588, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38250554

RESUMO

Objective: We analyzed the literature describing the results of treatment of colorectal cancer (CRC) using acupuncture in the past three decades from the Web of Science (WoS) and Chinese databases (including CNKI, WANGFANG and VIP), and summarized the current development of CRC treatment as well as future research directions through the presentation of maps and visualization analysis. Methods: We searched the WoS and Chinese databases. Relevant articles were exported, and the data were organized using Excel software and was visualized and analyzed using CiteSpace software. Results: A total of 355 articles from the WoS and 95 articles from Chinese databases were selected for inclusion in the analysis. The articles in WoS were sourced from 174 journals, 1274 institutions, and 66 countries, and covered 299 keywords. The articles in the Chinese databases were sourced from 43 journals, 111 institutions, and 3 countries, and included 126 keywords. The article with the most citations in the WoS was cited 128 times and in the Chinese databases, the article with the most citations was cited 120 times. Acupuncture, CRC, rectal cancer, apoptosis, warm acupuncture, traditional Chinese medicine (TCM) and gastrointestinal function were mentioned most frequently in the WoS. CRC, electroacupuncture, gastrointestinal function, rectal cancer, acupuncture and moxibustion, acupuncture, and colon cancer were mentioned most frequently in the Chinese databases. Conclusion: Both the WoS and Chinese databases showed a gradual increase in the number of articles related to acupuncture treatment for CRC, indicating a growing interest in this area. Acupuncture treatments are diverse, including warm acupuncture, auricular acupuncture, acupuncture injection, and electroacupuncture. They are often used in combination with drugs to treat symptoms such as depression, nausea and vomiting, pain, diarrhea, and urinary and fecal incontinence, which are commonly associated with CRC.

6.
Microorganisms ; 10(9)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144425

RESUMO

The increasing amount of agricultural applications of controlled-release urea (CRU) and fulvic acids (FA) demands a better understanding of FA's effects on microbially mediated nitrogen (N) nutrient cycling. Herein, a 0-60 day laboratory experiment and a consecutive pot experiment (2016-2018) were carried out to reveal the effects of using CRU on soil microbial N-cycling processes and soil fertility, with and without the application of FA. Compared to the CRU treatment, the CRU+FA treatment boosted wheat yield by 22.1%. To reveal the mechanism of CRU+FA affecting the soil fertility, soil nutrient supply and microbial community were assessed and contrasted in this research. From 0-60 days, compared with the CRU treatment, leaching NO3--N content of CRU+FA was dramatically decreased by 12.7-84.2% in the 20 cm depth of soil column. Different fertilizers and the day of fertilization both have an impact on the soil microbiota. The most dominant bacterial phyla Actinobacteria and Proteobacteria were increased with CRU+FA treatment during 0-60 days. Network analysis revealed that microbial co-occurrence grew more intensive during the CRU+FA treatment, and the environmental change enhanced the microbial community. The CRU+FA treatment, in particular, significantly decreased the relative abundance of Sphingomonas, Lysobacter and Nitrospira associated with nitrification reactions, Nocardioides and Gaiella related to denitrification reactions. Meanwhile, the CRU+FA treatment grew the relative abundance of Ensifer, Blastococcus, and Pseudolabrys that function in N fixation, and then could reduce NH4+-N and NO3--N leaching and improve the soil nutrient supply. In conclusion, the synergistic effects of slow nutrition release of CRU and growth promoting of FA could improve the soil microbial community of N cycle, reduce the loss of nutrients, and increase the wheat yield.

7.
Front Genet ; 12: 644143, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054916

RESUMO

Abnormal fibroblast differentiation into myofibroblast is a crucial pathological mechanism of pulmonary fibrosis (PF). Super-enhancers, a newly discovered cluster of regulatory elements, are regarded as the regulators of cell identity. We speculate that abnormal activation of super-enhancers must be involved in the pathological process of PF. This study aims to identify potential pathogenic super-enhancer-driven genes in PF. Differentially expressed genes (DEGs) in PF mouse lungs were identified from a GEO dataset (GDS1492). We collected super-enhancers and their associated genes in human lung fibroblasts and mouse embryonic fibroblasts from SEA version 3.0, a network database that provides comprehensive information on super-enhancers. We crosslinked upregulated DEGs and super-enhancer-associated genes in fibroblasts to predict potential super-enhancer-driven pathogenic genes in PF. A total of 25 genes formed an overlap, and the protein-protein interaction network of these genes was constructed by the STRING database. An interaction network of transcription factors (TFs), super-enhancers, and associated genes was constructed using the Cytoscape software. Gene enrichment analyses, including KEGG pathway and GO analysis, were performed for these genes. Latent transforming growth factor beta (TGF-ß) binding protein 2 (LTBP2), one of the predicted super-enhancer-driven pathogenic genes, was used to verify the predicted network's accuracy. LTBP2 was upregulated in the lungs of the bleomycin-induced PF mouse model and TGF-ß1-stimulated mouse and human fibroblasts. Myc is one of the TFs binding to the LTBP2 super-enhancer. Knockout of super-enhancer sequences with a CRISPR/Cas9 plasmid or inhibition of Myc all decreased TGF-ß1-induced LTBP2 expression in NIH/3 T3 cells. Identifying and interfering super-enhancers might be a new way to explore possible therapeutic methods for PF.

8.
Front Plant Sci ; 12: 759929, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975942

RESUMO

Controlled release phosphorus (P) fertilizers and humic acid (HA) applications are two effective and significant techniques or measures for preventing P loss and enhancing maize development. However, the underlying physiological mechanism of how the controlled release P fertilizers combined with HA affect the maize production and P-use efficiency (PUE) remains unknown. The effects of applying coated diammonium phosphate (CDAP) and HA together on soil nutrient supply intensity, soil phosphatase activity, photosynthesis, endogenous hormone contents, and yield of maize, as well as PUE, were examined in this study. In a pot experiment, two types of P fertilizers-CDAP and diammonium phosphate (DAP)- as well as two HA application rates (0 and 45 kg ha-1) and two P levels (60 and 75 kg P2O5 ha-1) were utilized. Results showed that the key elements that influence the growth and yield of the maize were the availability of P content in soil, plant photosynthesis, and hormone levels. The combination of CDAP and HA had a greater impact on yield and PUE over the course of 2 years than either DAP alone or DAP combined with HA. Besides, using CDAP in combination with HA increased the yield and PUE by 4.2 and 8.4%, respectively, as compared to the application of CDAP alone at 75 kg P2O5 ha-1. From the twelve-leaf to milk stages, the available P content in the soil was increased by an average of 38.6% with the combination of CDAP and HA compared to the application of CDAP alone at 75 kg P2O5 ha-1. In addition, the application of CDAP combined with HA boosted the activities of ATP synthase, as well as the content of cytokinin (CTK), and hence improved the maize photosynthetic rate (Pn). When compared to the application of CDAP alone or DAP combined with HA, the Pn of CDAP + HA treatments was enhanced by 17.9-35.1% at the same P rate. In conclusion, as an environmentally friendly fertilizer, the combined application of CDAP and HA improved the intensity of the soil nutrient supply, regulated photosynthetic capabilities, and increased the yield and PUE, which is important for agricultural production, P resource conservation, and environmental protection.

9.
Carbohydr Polym ; 251: 117060, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142612

RESUMO

Due to the poor controlled release ability, bio-based materials are difficult for large scale application on controlled release fertilizers (CRFs). Starch-based polyol (SP) and castor oil (CO) were mutually modified, and a cross-linked polymer film was formed on the surface of urea by in-situ reaction, which improved the slow release ability of the bio-based material. The results showed that increasing the CO ratio reduced porosity of coating and prolonged the nitrogen (N) release period, while the SP changed the high-temperature wrinkle characteristics and regulated the early N release rate. The mutual modification achieved an ultra-long release period of bio-based CRUs for 7 months. The degradation rate during nine months of bio-based coatings (5.05 %) was significantly higher than that of petroleum-based (3.74 %), and the coating was non-toxic to rice seeds. Mutual modification provided a safe and effective solution for the preparation of bio-based CRFs with long-term controlled release capability.


Assuntos
Óleo de Rícino/química , Reagentes de Ligações Cruzadas/química , Preparações de Ação Retardada/química , Fertilizantes/análise , Poliuretanos/química , Amido/química , Ureia/metabolismo , Preparações de Ação Retardada/farmacologia , Oryza/química , Polímeros/química , Ureia/química
10.
Sci Total Environ ; 789: 147778, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051498

RESUMO

Controlled-release urea (CRU) fertilizer application has been shown to improve crop yield and nitrogen (N) use efficiency. However, its effects when mixed with conventional urea fertilizer on soil aggregate stability, humic acid (HA) molecular composition and crop N uptake remain unclear. Soil and plant samples were collected from a long-term (2008-2019) experiment on field maize (Zea mays L., 'Zhengdan 958') which included two types of fertilizers [conventional urea fertilizer (CUF), blended CUF with CRU fertilizer (CRF)], four N application rates (0, 150, 300 and 450 kg ha-1), each in three replicates. The results showed that at 300 kg N ha-1, compared to CUF treatment, the CRF treatment significantly improved soil aggregate characteristics [aggregate content with particle size larger than 0.25 mm (R0.25) by 9.6%, mean weight diameter by 19.8%, and geometric mean diameter by 21.7%]. CRF treatment also increased HA content by 5.5%, fulvic acid (FA) by 5.5%, lignin-like molecules by 0.94 times, and protein-like molecules by 3.69 times. At grain-filling stage, CRF treatments significantly increased the sum of soil NH4+-N and NO3--N content by 23.3-24.5%, sap bleeding rate by 12.8-18.2% and N delivery rate through bleeding sap by 60.6-87.7% compared to CUF treatments at the same N application rate. At the same rate of N application, the CRF treatments significantly improved the average yield during three growing seasons by 9.4-14.0% in contrast with CUF treatments. The regression equations showed that the maximum yield was 8294 kg ha-1 for CUF at the application rate of 312 kg N ha-1 while it was 9890 kg ha-1 for CRF at the application rate of 286 kg N ha-1. We conclude that the long-term application of CRF changed the HA molecular structure, enhanced the water stable aggregates, improved crop N uptake, and increased economically viable maize yield.


Assuntos
Fertilizantes , Solo , Agricultura , Preparações de Ação Retardada , Substâncias Húmicas , Nitrogênio , Ureia , Zea mays
11.
ACS Omega ; 5(28): 17255-17265, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32715211

RESUMO

Urea phosphate (UP) is an acidic compound fertilizer, which significantly improves the low efficiency of P application caused by high pH in saline-alkali soil. In this study, urea phosphate potassium (UPK) was prepared by adding potassium chloride (KCl) to modify urea phosphate (UP) and the optimal combination of the synthetic process parameters was obtained using the response surface methodology at a four-variable, three-level experiment Box-Behnken design. Parameters such as the reaction temperature, KCl molar number, reaction time, and concentration of phosphoric acid were included for optimization. The thermostability, crystal structure, and microscopic morphology of UPK were measured by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. The fertilizer efficiency was validated in an experiment on maize grown in pots containing saline-alkali soil. The highest K2O content and UPK yield were obtained by using the following parameters: reaction time of 60 min, KCl of 0.32 mol, reaction temperature of 78 °C, and phosphoric acid concentration of 70%. Under optimal conditions, the predicted K2O value content and UPK yield were 3.51% and 69.8%, respectively. The experimental K2O content and UPK yield were 3.42 ± 0.35% and 67.58 ± 1.25%, respectively, which confirmed the strength of the predicted model. This model can be used as an effective tool to predict the K2O content and yield in UPK. Characterizations showed that KCl was uniformly distributed in UPK and its fluidity was effectively improved as observed in the angle-of-repose results. Compared to a conventional phosphorus fertilizer diammonium phosphate (DAP), the yield, total P use efficiency, soil available phosphorus content, and soil acid phosphatase activity of UPK increased significantly by 25.58, 174.5, 24.41, and 41.25%, respectively, and the soil pH on UPK treatments decreased by 3.98% significantly. In conclusion, this novel technology to modify UP by using KCl has an enormous potential for large-scale applications to satisfy the increasing demand for UP fertilizers on saline-alkali soil.

12.
Environ Sci Pollut Res Int ; 25(32): 32395-32408, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30229496

RESUMO

Phosphorus loading from external and internal sources poses a potential risk to eutrophication of lakes or reservoirs. However, the relative contribution of external and internal sources to eutrophication is still unclear especially for reservoirs with water transfer disturbance. The objective of this paper is to estimate the phosphorus loading from external (water transfer and diffusing emission) and internal sources (sediment release) in Yuqiao Reservoir (YQR) and compare their relative contribution of external and internal sources. In this study, we estimated the phosphorus loading considering both external (water transfer and diffusing source emission) and internal (release from sediment) sources of YQR. The phosphorus loading from water transfer was estimated by total phosphorus (TP) concentration × monthly flow of inflow. The phosphorus loading from nonpoint source emission was estimated using a generalized watershed loading function (GWLF). The phosphorus loading from internal sources was estimated with a Bayesian phosphorus budget model. Our result showed that water transfer TP load is the biggest (45.2%) source of TP load in YQR and internal TP load (20.5%) accounts for a comparable proportion of TP load as nonpoint source (34.3%) in YQR and dominates the total loading in some months. Analysis of seasonal total phosphorus load apportionment indicated that water transfer TP load takes the largest proportion in winter (60.8%), spring (60.2%), and autumn (47.8%). Nonpoint source TP load takes the largest proportion in summer (60.1%), and internal TP load is the second source of YQR in summer (22.4%). Our study indicates that water transfer may be the major driver of eutrophication for some reservoir systems, and sediment release may prevent recovery of many eutrophic lakes and reservoirs. Our analysis suggests that TP pollution control strategies in YQR should be preferentially focused on the improvement of water quality in the upstream reservoir, and nonpoint source TP load reductions should be focused on summer. Compared with conventional nutrient apportionment model applications, this paper provides a new approach to estimate external and internal TP loads simultaneously. Graphical abstract ᅟ.


Assuntos
Eutrofização , Lagos/química , Fósforo/análise , Estações do Ano , Movimentos da Água , Poluentes Químicos da Água/análise , Água/química , Teorema de Bayes , China , Difusão , Monitoramento Ambiental , Nitrogênio , Nutrientes , Qualidade da Água , Abastecimento de Água
13.
Huan Jing Ke Xue ; 35(6): 2139-47, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25158488

RESUMO

Regional Nutrient Management (ReNuMa) was applied to estimate dissolved nitrogen (DN) load and perform source apportionment in Shuaishui watershed during 2000-2010. Satisfactory performance of ReNuMa was revealed by the E(ns) and R2 of greater than 0.9 in calibrating and validating streamflow and DN. The average nonpoint DN load in this watershed was 1.11 x 10(3) t x a(-1), with the load intensity of (0.75 +/- 0.22) t x km(-2). Among all the land uses, paddy field had the largest DN load intensity [28.60 kg x (hm2 x a)(-1)], while forest had the least [2.71 kg x (hm2 x a)(-1)]. Agricultural land (including paddy, grain, cash crop, tea plant and orchard) contributed most to DN load in Shuaishui watershed, indicating that the human dominated agricultural activities was the major contributor of nonpoint source pollution. Land use structure optimization for Shuaishui watershed in 2015 was conducted under the rule of reducing pollutants loads and maximizing the agricultural output value. The results demonstrated that agricultural monetary growth was accompanied with the increasing DN load at the optimal level, although output increment was higher than that of DN load.


Assuntos
Agricultura , Monitoramento Ambiental , Nitrogênio/análise , Poluentes Químicos da Água/análise , China
14.
Enzyme Microb Technol ; 53(6-7): 365-72, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24315638

RESUMO

Rational design was applied to glucose 1-dehydrogenase (LsGDH) from Lysinibacillus sphaericus G10 to improve its thermal stability by introduction of disulfide bridges between subunits. One out of the eleven mutants, designated as DS255, displayed significantly enhanced thermal stability with considerable soluble expression and high specific activity. It was extremely stable at pH ranging from 4.5 to 10.5, as it retained nearly 100% activity after incubating at different buffers for 1h. Mutant DS255 also exhibited high thermostability, having a half-life of 9900min at 50°C, which was 1868-fold as that of its wild type. Moreover, both of the increased free energy of denaturation and decreased entropy of denaturation of DS255 suggested that the enzyme structure was stabilized by the engineered disulfide bonds. On account of its robust stability, mutant DS255 would be a competitive candidate in practical applications of chiral chemicals synthesis, biofuel cells and glucose biosensors.


Assuntos
Glucose 1-Desidrogenase/química , Glucose 1-Desidrogenase/metabolismo , Bacillaceae/enzimologia , Bacillaceae/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cisteína/química , Dissulfetos/química , Estabilidade Enzimática , Glucose 1-Desidrogenase/genética , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Desnaturação Proteica , Engenharia de Proteínas , Estrutura Quaternária de Proteína , Subunidades Proteicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência , Temperatura
15.
PLoS One ; 7(3): e33551, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22442697

RESUMO

The performances of nine biosorbents derived from dead fungal biomass were investigated for their ability to remove Reactive Black 5 from aqueous solution. The biosorption data for removal of Reactive Black 5 were readily modeled using the Langmuir adsorption isotherm. Kinetic analysis based on both pseudo-second-order and Weber-Morris models indicated intraparticle diffusion was the rate limiting step for biosorption of Reactive Black 5 on to the biosorbents. Sorption capacities of the biosorbents were not correlated with the initial biosorption rates. Sensitivity analysis of the factors affecting biosorption examined by an artificial neural network model showed that pH was the most important parameter, explaining 22%, followed by nitrogen content of biosorbents (16%), initial dye concentration (15%) and carbon content of biosorbents (10%). The biosorption capacities were not proportional to surface areas of the sorbents, but were instead influenced by their chemical element composition. The main functional groups contributing to dye sorption were amine, carboxylic, and alcohol moieties. The data further suggest that differences in carbon and nitrogen contents of biosorbents may be used as a selection index for identifying effective biosorbents from dead fungal biomass.


Assuntos
Biomassa , Fungos/química , Modelos Biológicos , Naftalenossulfonatos/química , Microbiologia do Solo
16.
Huan Jing Ke Xue ; 32(11): 3300-4, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22295627

RESUMO

The concentration, composition and characteristic parameters of 18 surface sediment samples collected from Jinzhou Bay were studied. The samples were soxhlet-extracted with a mixture of 1: 1 (V/V) dichloromethane-hexane and analyzed by GC-MS after purification and concentration. Concentrations of n-alkanes vary from 1.9 to 4.2 microg x g(-1) with an average value of 2.6 microg x g(-1) dry weight. n-Alkanes distribution patterns of all positions were characterized by double peak-cluster, which means double sources from terrestrial and marine origin. The sum of nC25 to nC31 accounts for 20%-32% of the total n-alkanes, while the average value of L/H, C31/C19, TAR ratio are 0.67, 3.06, 2.02, respectively. All of these three indices suggest that the terrestrial contributions are higher than marine sources, especially for No. 2, 3 and 7 stations, which were influenced by riverinput nearby. Carbon Preference Index (CPI) ranges from 1.19 to 2.63 with an average value of 1.73, which is close to 1; the ratio of Pristane/Phytane (Pr/Ph) and unresolved/resolved compounds (U/R) range from 0.91 to 1.28, 2.2 to 4.3, respectively. All of these three parameters indicate that No. 13 and 15 stations are influenced by petroleum pollution. Comprehensive analysis of various parameters shows that Jinzhou Bay is threatened by both terrestrial inputs and petroleum hydrocarbons contaminations, which may relate to river discharging and port shipping in Jinzhou Bay.


Assuntos
Alcanos/análise , Sedimentos Geológicos/química , Petróleo/análise , Água do Mar/análise , Poluentes Químicos da Água/análise , Baías/química , China , Cromatografia Gasosa-Espectrometria de Massas
17.
Bioresour Technol ; 102(2): 828-34, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20869234

RESUMO

The main objective of this work was to investigate the biosorption performance of nonviable Penicillium YW 01 biomass for removal of Acid Black 172 metal-complex dye (AB) and Congo Red (CR) in solutions. Maximum biosorption capacities of 225.38 and 411.53 mg g(-1) under initial dye concentration of 800 mg L(-1), pH 3.0 and 40 °C conditions were observed for AB and CR, respectively. Biosorption data were successfully described with Langmuir isotherm and the pseudo-second-order kinetic model. The Weber-Morris model analysis indicated that intraparticle diffusion was the limiting step for biosorption of AB and CR onto biosorbent. Analysis based on the artificial neural network and genetic algorithms hybrid model indicated that initial dye concentration and temperature appeared to be the most influential parameters for biosorption process of AB and CR onto biosorbent, respectively. Characterization of the biosorbent and possible dye-biosorbent interaction were confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy.


Assuntos
Vermelho Congo/isolamento & purificação , Complexos de Coordenação/isolamento & purificação , Viabilidade Microbiana , Naftalenossulfonatos/isolamento & purificação , Redes Neurais de Computação , Penicillium/metabolismo , Compostos de Enxofre/isolamento & purificação , Temperatura , Água/química , Adsorção , Biodegradação Ambiental , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Modelos Biológicos , Penicillium/crescimento & desenvolvimento , Penicillium/ultraestrutura , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
18.
Bioresour Technol ; 102(2): 1528-36, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20805024

RESUMO

The gene gdh encoding an organic solvent-tolerant and alkaline-resistant NAD(P)-dependent glucose 1-dehydrogenase (LsGDH) was cloned from Lysinibacillus sphaericus G10 and expressed in Escherichia coli. The recombinant LsGDH exhibited maximum activity at pH 9.5 and 50 °C. LsGDH displayed high stability at a wide pH ranging from 6.5 to 10.0 and was stable after incubation at 30 °C for 1 week in 25 mM sodium phosphate buffer (pH 6.5) in the absence or presence of NaCl. The activity of LsGDH was enhanced by Li+, Na+, K+, NH4+, Mg2+, and EDTA at pH 8.0. LsGDH exhibited high tolerance to 60% DMSO, 30% acetone, 30% methanol, 30% ethanol, 10% n-propanol, 30% isopropanol, 60% n-hexanol and 30% n-hexane. The relationship between stability and chain length of the alcohols fit a Gaussian distribution model (R2≥0.94), and demonstrated lowest enzyme stability in C4-alcohol. The results suggested that LsGDH was potentially useful for coenzyme regeneration in organic solvents or under alkaline conditions.


Assuntos
Álcalis/farmacologia , Bacillus/enzimologia , Bacillus/genética , Escherichia coli/metabolismo , Glucose 1-Desidrogenase/genética , Compostos Orgânicos/farmacologia , Solventes/farmacologia , Sequência de Aminoácidos , Bacillus/efeitos dos fármacos , Clonagem Molecular , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Genes Bacterianos/genética , Glucose 1-Desidrogenase/química , Glucose 1-Desidrogenase/isolamento & purificação , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Íons , Cinética , Metais/farmacologia , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade por Substrato/efeitos dos fármacos , Temperatura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA