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1.
Echocardiography ; 41(5): e15826, 2024 May.
Article in English | MEDLINE | ID: mdl-38678584

ABSTRACT

This case report describes a 35-year-old female patient who presented with palpitations and shortness of breath. Imaging findings suggested a cardiac tumor, histopathology confirmed primary cardiac angiosarcoma. This tumor is highly aggressive, usually occurs in the right atrium, lacks specificity in clinical presentation, is prone to early metastasis, and has a poor prognosis. Echocardiography is the method of choice for early detection and is important in assessing tumor size, location, mode of attachment and whether cardiac function is impaired.


Subject(s)
Echocardiography , Heart Neoplasms , Hemangiosarcoma , Humans , Heart Neoplasms/diagnostic imaging , Heart Neoplasms/diagnosis , Female , Hemangiosarcoma/diagnostic imaging , Hemangiosarcoma/diagnosis , Adult , Echocardiography/methods , Heart Atria/diagnostic imaging , Diagnosis, Differential
2.
Nano Lett ; 24(10): 3282-3289, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38421230

ABSTRACT

X-ray radiation information storage, characterized by its ability to detect radiation with delayed readings, shows great promise in enabling reliable and readily accessible X-ray imaging and dosimetry in situations where conventional detectors may not be feasible. However, the lack of specific strategies to enhance the memory capability dramatically hampers its further development. Here, we present an effective anion substitution strategy to enhance the storage capability of NaLuF4:Tb3+ nanocrystals attributed to the increased concentration of trapping centers under X-ray irradiation. The stored radiation information can be read out as optical brightness via thermal, 980 nm laser, or mechanical stimulation, avoiding real-time measurement under ionizing radiation. Moreover, the radiation information can be maintained for more than 13 days, and the imaging resolution reaches 14.3 lp mm-1. These results demonstrate that anion substitution methods can effectively achieve high storage capability and broaden the application scope of X-ray information storage.

3.
Cell Rep ; 42(11): 113348, 2023 11 28.
Article in English | MEDLINE | ID: mdl-37910509

ABSTRACT

Promoters are essential tools for basic and translational neuroscience research. An ideal promoter should possess the shortest possible DNA sequence with cell-type selectivity. However, whether ultra-compact promoters can offer neuron-specific expression is unclear. Here, we report the development of an extremely short promoter that enables selective gene expression in neurons, but not glial cells, in the brain. The promoter sequence originates from the human CALM1 gene and is only 120 bp in size. The CALM1 promoter (pCALM1) embedded in an adeno-associated virus (AAV) genome directed broad reporter expression in excitatory and inhibitory neurons in mouse and monkey brains. Moreover, pCALM1, when inserted into an all-in-one AAV vector expressing SpCas9 and sgRNA, drives constitutive and conditional in vivo gene editing in neurons and elicits functional alterations. These data demonstrate the ability of pCALM1 to conduct restricted neuronal gene expression, illustrating the feasibility of ultra-miniature promoters for targeting brain-cell subtypes.


Subject(s)
Neurons , RNA, Guide, CRISPR-Cas Systems , Mice , Animals , Humans , Neurons/metabolism , Brain/metabolism , Neuroglia/metabolism , Genetic Therapy , Genetic Vectors/genetics , Dependovirus/genetics , Dependovirus/metabolism
4.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4365-4371, 2022 Aug.
Article in Chinese | MEDLINE | ID: mdl-36046863

ABSTRACT

This study was designed to explore the potential of gypenosides as a novel natural stabilizer for the production of nanosuspensions. The gypenosides-stabilized quercetin nanosuspensions(QUE-NS) were prepared using the high-speed shearing and high-pressure homogenization method with quercetin as a model drug, followed by their in vitro evaluation.Based on the measured mean particle size and polydispersity index(PDI) of QUE-NS,the single factor experiment was conducted to optimize the preparation process parameters.The freeze-drying method was used to transform QUE-NS into freeze-dried powders, whose storage stability and saturation solubility were then studied.Moreover, the effects of pH and ionic strength on the physical stability of the nanosuspension system were examined.According to the results, the optimized process parameters were listed as follows: shear rate 13 000 r·min~(-1),shear time 2 min, homogenization pressure 100 MPa, and homogenization frequency 12 times.The mean particle size of QUE-NS prepared under the optimum process conditions was(461.9±2.4) nm, and the PDI was 0.059±0.016.During the two months of storage at room temperature, the freeze-dried QUE-NS powders remained stable.The saturation solubility of freeze-dried QUE-NS powders was proved higher than those of quercetin and the physical mixture.The results of stability testing demonstrated that QUE-NS stabilized with gypenosides exhibited good stability within the pH range of 6 to 8,while coalescence was prone to occur in the presence of salt.Overall, gypenosides is expected to become a new natural stabilizer for the preparation of nanosuspensions.


Subject(s)
Nanoparticles , Quercetin , Drug Stability , Gynostemma , Particle Size , Plant Extracts , Powders , Solubility , Suspensions
5.
Brain Res Bull ; 174: 281-295, 2021 09.
Article in English | MEDLINE | ID: mdl-34216649

ABSTRACT

Rehmannia glutinosa, the fresh or dried root of Rehmannia glutinosa (Gaertn.) Libosch. ex Fisch. & Mey., and Gardenia, the fruit of Gardenia jasminoides Ellis from Rubiaceae, both are famous traditional Chinese medicines that have been traditionally used in China. Catalpol and geniposide, as two kinds of iridoid glycosides with high activities, are the main bioactive components in Rehmannia glutinosa and Gardenia jasminoides Ellis, respectively. Over the past few decades, catalpol and geniposide have been widely studied for their therapeutic effects. The preclinical experiments demonstrated that they possessed significant neuroprotective activities against Alzheimer's disease, Parkinson's disease, stroke, and depression, etc. In this paper, the pharmacological effects and mechanisms of catalpol and geniposide on Alzheimer's disease and Parkinson's disease from 2005 to now were systematically summarized and comprehensively analyzed. At the same time, the pharmacokinetic characteristics of the analyzed compounds were also described, hoping to provide some enlightenment for the design, research, and development of iridoid glycosides.


Subject(s)
Alzheimer Disease/drug therapy , Antiparkinson Agents/therapeutic use , Iridoid Glucosides/therapeutic use , Iridoids/therapeutic use , Parkinson Disease/drug therapy , Animals , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Gardenia/chemistry , Humans , Iridoid Glucosides/pharmacology , Iridoids/pharmacology , Medicine, Chinese Traditional , Rehmannia/chemistry
6.
Arch Pharm Res ; 44(7): 633-654, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34269984

ABSTRACT

Atractylodes macrocephala Koidz is a widely used as a traditional Chinese medicine. Atractylenolides (-I, -II, and -III) are a class of lactone compounds derived from Atractylodes macrocephala Koidz. Research into atractylenolides over the past two decades has shown that atractylenolides have anti-cancer, anti-inflammatory, anti-platelet, anti-osteoporosis, and antibacterial activity; protect the nervous system; and regulate blood glucose and lipids. Because of structural differences, both atractylenolide-I and atractylenolide-II have remarkable anti-cancer activities, and atractylenolide-I and atractylenolide-III have remarkable anti-inflammatory and neuroprotective activities. We therefore recommend further clinical research on the anti-cancer, anti-inflammatory and neuroprotective effects of atractylenolides, determine their therapeutic effects, alone or in combination. To investigate their ability to regulate blood glucose and lipid, as well as their anti-platelet, anti-osteoporosis, and antibacterial activities, both in vitro and in vivo studies are necessary. Atractylenolides are rapidly absorbed but slowly metabolized; thus, solubilization studies may not be necessary. However, due to the inhibitory effects of atractylenolides on metabolic enzymes, it is necessary to pay attention to the possible side effects of combining atractylenolides with other drugs, in clinical application. In short, atractylenolides have considerable medicinal value and warrant further study.


Subject(s)
Atractylodes/chemistry , Lactones/pharmacology , Sesquiterpenes/pharmacology , Animals , Disease Models, Animal , Humans , Inflammation/drug therapy , Lactones/therapeutic use , Medicine, Chinese Traditional/methods , Mice , Neoplasms/drug therapy , Nervous System Diseases/drug therapy , Rhizome/chemistry , Sesquiterpenes/therapeutic use
7.
Chin Med ; 16(1): 46, 2021 Jun 19.
Article in English | MEDLINE | ID: mdl-34147113

ABSTRACT

Musk, the dried secretion from the musk sac gland which is located between the navel and genitals of mature male musk deer, is utilized as oriental medicine in east Asia. It has been utilized to treat conditions such as stroke, coma, neurasthenia, convulsions, and heart diseases in China since ancient times. This paper aims to provide a comprehensive overview of musk in zoology, chemical composition, pharmacology, clinical applications, and quality control according to the up-to-date literature. Studies found that musk mainly contains macrocyclic ketones, pyridine, steroids, fatty acids, amino acids, peptides, and proteins, whilst the main active ingredient is muscone. Modern pharmacological studies have proven that musk possesses potent anti-inflammatory effects, neuroprotective effects, anti-cancer effects, antioxidant effects, etc. Moreover, muscone, the main active ingredient, possesses anti-inflammatory, neuroprotective, antioxidant, and other pharmacological effects. In the quality control of musk, muscone is usually the main detection indicator, and the common analytical method is GC, and researchers have established novel and convenient methods such as HPLC-RI, RP-UPLC-ELSD, and Single-Sweep Polarography. In addition, quality evaluation methods based on steroids and the bioactivity of musk have been established. As for the identification of musk, due to various objective factors such as the availability of synthetic Muscone, it is not sufficient to rely on muscone alone as an identification index. To date, some novel technologies have also been introduced into the identification of musk, such as the electronic nose and DNA barcoding technology. In future research, more in vivo experiments and clinical studies are encouraged to fully explain the pharmacological effects and toxicity of musk, and more comprehensive methods are needed to evaluate and control the quality of musk.

8.
Bioresour Technol ; 326: 124751, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33535152

ABSTRACT

Pretreatment plays a key role in biofuel production from lignocellulosic biomass. In this study, the main factors of peroxyformic acid (PA) pretreatment were optimized in the light of enzymolysis efficiency and composition analysis of pretreated sugarcane bagasse (SCB). Lignin was significantly removed (59.0%) and a complete saccharification level (103.6%) was obtained for the pretreated SCB with slight cellulose loss (9.2%) under the optimized pretreatment conditions. The effects of PA pretreatment on the structural characteristics of SCB were also studied and the digestibility of pretreated SCB was also evaluated by dark fermentative hydrogen production with an enriched anaerobic cellulolytic microbial consortium MC1. The hydrogen production increased by 195.5% (based on initial SCB) and the abundance of dominant hemicellulose-degradation genus Thermoanaerobacterium increased from 23.8% to 40.2% due to the remaining and accessible hemicellulose in PA pretreated SCB.


Subject(s)
Cellulase , Saccharum , Cellulose , Formates , Hydrogen , Hydrolysis , Lignin
9.
Expert Rev Anti Infect Ther ; 19(7): 911-925, 2021 07.
Article in English | MEDLINE | ID: mdl-33346681

ABSTRACT

Introduction: Calycosin (CA), a typical phytoestrogen extracted from root of Astragalus membranaceus. On the basis of summarizing the pharmacological and pharmacokinetic studies of CA in recent years, we hope to provide useful information for CA about treating different diseases and to make suggestions for future research.Areas covered: We collected relevant information (January 2014 to March 2020) on CA via the Internet database. Keywords searched includ pharmacology, pharmacokinetics and toxicology, and the number of effective references was 118. CA is a phytoestrogen with wide range of pharmacological activities. By affecting PI3K/Akt/mTOR, WDR7-7-GPR30, Rab27B-ß-catenin-VEGF, etc. signaling pathway, CA showed the effect of anticancer, anti-inflammatory, anti-osteoporosis, neuroprotection, hepatoprotection, etc. Therefore, CA is prospective to be used in the treatment of many diseases.Expert opinion: Research shows that CA has a therapeutic effect on a variety of diseases. We think CA is a promising natural medicine. Therefore, we propose that the research directions of CA in the future include the following. Carrying out clinical research trials in order to find the most suitable medicinal concentration for different diseases; Exploring the synergistic mechanism of CA in combination with other drugs; Exploring ways to increase the blood circulation concentration of CA.


Subject(s)
Drugs, Chinese Herbal/chemistry , Isoflavones/pharmacology , Phytoestrogens/pharmacology , Animals , Astragalus propinquus , Humans , Isoflavones/adverse effects , Isoflavones/isolation & purification , Phytoestrogens/adverse effects , Phytoestrogens/isolation & purification
10.
Pharmacol Res ; 164: 105373, 2021 02.
Article in English | MEDLINE | ID: mdl-33316380

ABSTRACT

Lupeol is a natural triterpenoid that widely exists in edible fruits and vegetables, and medicinal plants. In the last decade, a plethora of studies on the pharmacological activities of lupeol have been conducted and have demonstrated that lupeol possesses an extensive range of pharmacological activities such as anticancer, antioxidant, anti-inflammatory, and antimicrobial activities. Pharmacokinetic studies have indicated that absorption of lupeol by animals was rapid despite its nonpolar characteristics, and lupeol belongs to class II BCS (biopharmaceutics classification system) compounds. Moreover, the bioactivities of some isolated or synthesized lupeol derivatives have been investigated, and these results showed that, with modification to C-3 or C-19, some derivatives exhibit stronger activities, e.g., antiprotozoal or anticancer activity. This review aims to summarize the advances in pharmacological and pharmacokinetic studies of lupeol in the last decade with an emphasis on its anticancer and anti-inflammatory activities, as well as the research progress of lupeol derivatives thus far, to provide researchers with the latest information, point out the limitations of relevant research at the current stage and the aspects that should be strengthened in future research.


Subject(s)
Anti-Inflammatory Agents , Antineoplastic Agents , Pentacyclic Triterpenes , Animals , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Humans , Pentacyclic Triterpenes/pharmacokinetics , Pentacyclic Triterpenes/pharmacology , Pentacyclic Triterpenes/therapeutic use , Treatment Outcome
11.
Chin Med ; 15: 102, 2020.
Article in English | MEDLINE | ID: mdl-32994803

ABSTRACT

Scutellaria baicalensis Georgi. (SB) is a common heat-clearing medicine in traditional Chinese medicine (TCM). It has been used for thousands of years in China and its neighboring countries. Clinically, it is mostly used to treat diseases such as cold and cough. SB has different harvesting periods and processed products for different clinical symptoms. Botanical researches proved that SB included in the Chinese Pharmacopoeia (1st, 2020) was consistent with the medicinal SB described in ancient books. Modern phytochemical analysis had found that SB contains hundreds of active ingredients, of which flavonoids are its major components. These chemical components are the material basis for SB to exert pharmacological effects. Pharmacological studies had shown that SB has a wide range of pharmacological activities such as antiinflammatory, antibacterial, antiviral, anticancer, liver protection, etc. The active ingredients of SB were mostly distributed in liver and kidney, and couldn't be absorbed into brain via oral absorption. SB's toxicity was mostly manifested in liver fibrosis and allergic reactions, mainly caused by baicalin. The non-medicinal application prospects of SB were broad, such as antibacterial plastics, UV-resistant silk, animal feed, etc. In response to the Coronavirus Disease In 2019 (COVID-19), based on the network pharmacology research, SB's active ingredients may have potential therapeutic effects, such as baicalin and baicalein. Therefore, the exact therapeutic effects are still need to be determined in clinical trials. SB has been reviewed in the past 2 years, but the content of these articles were not comprehensive and accurate. In view of the above, we made a comprehensive overview of the research progress of SB, and expect to provide ideas for the follow-up study of SB.

12.
Int J Pharm ; 583: 119406, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32387309

ABSTRACT

Tea saponins (TS), a novel multifunctional stabilizer, were explored to stabilize the nanosuspensions. The purpose of this study was to investigate the effect of TS on the stability and redispersibility of nanosuspensions. In present work, hesperidin (HDN), a poorly soluble drug, was used as a model drug. HDN nanosuspensions (HDN-NS) with particle size of 250-270 nm were prepared by high-speed shearing and high-pressure homogenization. The zeta potential of HDN-NS was -23.16 ± 1.12 mV. Compared with traditional stabilizers, TS were superior in stabilization efficiency at low concentrations. Nanosuspensions freeze-dried powder using TS and lactose as cryoprotectants had good redispersibility, and the average particle size was 266.5 ± 9.0 nm after reconstitution. TS and lactose can effectively prevent the irreversible agglomeration of HDN-NS during freeze-drying. The dissolution was enhanced owing to particle size reduction. Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) results showed that HDN nanocrystals were irregularly lumpy. The chemical structure and crystal state of HDN had not significantly changed during production. In conclusion, TS have the potential to stabilize and disperse nanosuspensions and provide a promising strategy for the development of poorly soluble drugs.


Subject(s)
Camellia sinensis , Excipients/chemistry , Hesperidin/chemistry , Nanoparticles , Saponins/chemistry , Camellia sinensis/chemistry , Cryoprotective Agents/chemistry , Drug Compounding , Drug Liberation , Drug Stability , Feasibility Studies , Freeze Drying , Lactose/chemistry , Saponins/isolation & purification , Solubility , Surface Properties
13.
Eur J Pharmacol ; 879: 173124, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32339515

ABSTRACT

As a naturally occurring furanocoumarin, the medicinal value of imperatorin has been studied more and more. We hope to provide useful information for the further development of imperatorin by analyzing the literature of imperatorin in recent years. By collating the literature on the pharmacology of imperatorin, we found that the pharmacological activity of imperatorin is wide and imperatorin can be used for anti-cancer, neuroprotection, anti-inflammatory, anti-hypertension and antibacterial. In addition, we found that some researchers confirmed the toxicity of imperatorin. Pharmacokinetic studies demonstrated that oxidation metabolism is the main metabolic pathways of imperatorin. At present, the shortcomings of research on imperatorin mainly include: most pharmacological studies are concentrated in vitro, lacking enough in vivo experimental data; more and more studies showed that imperatorin has synergistic effect with other drugs in anticancer and other aspects, but lacking the detailed explanation of the mechanism of the synergistic effect; imperatorin has side effect, but it lacks enough experimental conclusions. Based on the above defects, we believe that more in vivo experiments of imperatorin should be carried out in the future; future research need to explore synergistic mechanisms of imperatorin with other drugs, especially in anticancer; the dose affects both the pharmacological activity and the side effect of imperatorin. The relationship between the dose and the two aspects need to be further studied in order to reduce the side effect. In addition, through structural modification of imperatorin, it is possible to improve the treatment effect and reduce side effect.


Subject(s)
Anti-Inflammatory Agents , Antineoplastic Agents, Phytogenic , Furocoumarins , Neuroprotective Agents , Animals , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/toxicity , Antineoplastic Agents, Phytogenic/pharmacokinetics , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/toxicity , Furocoumarins/pharmacokinetics , Furocoumarins/pharmacology , Furocoumarins/toxicity , Humans , Neuroprotective Agents/pharmacokinetics , Neuroprotective Agents/pharmacology , Neuroprotective Agents/toxicity
14.
Chaos ; 26(8): 084313, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27586630

ABSTRACT

In the present paper, multi-degree-of-freedom strongly nonlinear systems are modeled as quasi-Hamiltonian systems and the stochastic averaging method for quasi-Hamiltonian systems (including quasi-non-integrable, completely integrable and non-resonant, completely integrable and resonant, partially integrable and non-resonant, and partially integrable and resonant Hamiltonian systems) driven by fractional Gaussian noise is introduced. The averaged fractional stochastic differential equations (SDEs) are derived. The simulation results for some examples show that the averaged SDEs can be used to predict the response of the original systems and the simulation time for the averaged SDEs is less than that for the original systems.

15.
Gene ; 584(2): 185-94, 2016 Jun 15.
Article in English | MEDLINE | ID: mdl-26915487

ABSTRACT

Microbial remediation has become one of the most important strategies for eliminating petroleum pollutants. Revealing the transcript maps of microorganisms with the hydrocarbon-degrading ability contributes to enhance the degradation of hydrocarbons and further improve the effectiveness of bioremediation. In this study, we characterized the transcriptome of hydrocarbon-degrading Achromobacter sp. HZ01 after petroleum treatment for 16h. A total of 38,706,280 and 38,954,413 clean reads were obtained by RNA-seq for the petroleum-treated group and control, respectively. By an effective de novo assembly, 3597 unigenes were obtained, including 3485 annotated transcripts. Petroleum treatment had significantly influenced the transcriptional profile of strain HZ01, involving 742 differentially expressed genes. A part of genes were activated to exert specific physiological functions, whereas more genes were down-regulated including specific genes related to cell motility, genes associated with glycometabolism, and genes coding for ribosomal proteins. Identification of genes related to petroleum degradation revealed that the fatty acid metabolic pathway and a part of monooxygenases and dehydrogenases were activated, whereas the TCA cycle was inactive. Additionally, terminal oxidation might be a major aerobic pathway for the degradation of n-alkanes in strain HZ01. The newly obtained data contribute to better understand the gene expression profiles of hydrocarbon-degrading microorganisms after petroleum treatment, to further investigate the genetic characteristics of strain HZ01 and other related species and to develop cost-effective and eco-friendly strategies for remediation of crude oil-polluted environments.


Subject(s)
Achromobacter/genetics , Hydrocarbons/metabolism , Transcriptome , Achromobacter/metabolism , Down-Regulation , Gene Expression Regulation, Bacterial , Genes, Bacterial , Transcription, Genetic , Up-Regulation
16.
Chemistry ; 21(24): 8918-25, 2015 Jun 08.
Article in English | MEDLINE | ID: mdl-25925691

ABSTRACT

Nanocomposites based on molybdenum disulfide (MoS2 ) and different carbon modifications are intensively investigated in several areas of applications due to their intriguing optical and electrical properties. Addition of a third element may enhance the functionality and application areas of such nanocomposites. Herein, we present a facile synthetic approach based on directed thermal decomposition of (Ph4 P)2 MoS4 generating MoS2 nanocomposites containing carbon and phosphorous. Decomposition at 250 °C yields a composite material with significantly enlarged MoS2 interlayer distances caused by in situ formation of Ph3 PS bonded to the MoS2 slabs through MoS bonds and (Ph4 P)2 S molecules in the van der Waals gap, as was evidenced by (31) P solid-state NMR spectroscopy. Visible-light-driven hydrogen generation demonstrates a high catalytic performance of the materials.

17.
Sci Rep ; 5: 8839, 2015 Mar 06.
Article in English | MEDLINE | ID: mdl-25744694

ABSTRACT

Three dimensional (3D) elastic hybrid networks built from interconnected nano- and microstructure building units, in the form of semiconducting-carbonaceous materials, are potential candidates for advanced technological applications. However, fabrication of these 3D hybrid networks by simple and versatile methods is a challenging task due to the involvement of complex and multiple synthesis processes. In this paper, we demonstrate the growth of Aerographite-GaN 3D hybrid networks using ultralight and extremely porous carbon based Aerographite material as templates by a single step hydride vapor phase epitaxy process. The GaN nano- and microstructures grow on the surface of Aerographite tubes and follow the network architecture of the Aerographite template without agglomeration. The synthesized 3D networks are integrated with the properties from both, i.e., nanoscale GaN structures and Aerographite in the form of flexible and semiconducting composites which could be exploited as next generation materials for electronic, photonic, and sensors applications.

18.
PLoS One ; 9(9): e106991, 2014.
Article in English | MEDLINE | ID: mdl-25208080

ABSTRACT

ZnO particles of different size and structures were used as fillers to modify the silicone rubber, in order to reveal the effect of the filler shape in the polymer composites. Tetrapodal shaped microparticles, short microfibers/whiskers, and nanosized spherical particles from ZnO have been used as fillers to fabricate the different ZnO-Silicone composites. The detailed microstructures of the fillers as well as synthesized composites using scanning electron microscopy have been presented here. The tensile elastic modulus and water contact angle, which are important parameters for bio-mimetic applications, of fabricated composites with different fillers have been measured and compared. Among all three types of fillers, tetrapodal shaped ZnO microparticles showed the best performance in terms of increase in hydrophobicity of material cross-section as well as the stiffness of the composites. It has been demonstrated that the tetrapodal shaped microparticles gain their advantage due to the special shape, which avoids agglomeration problems as in the case for nanoparticles, and the difficulty of achieving truly random distribution for whisker fillers.


Subject(s)
Composite Resins/chemistry , Dimethylpolysiloxanes/chemistry , Silicon/chemistry , Zinc Oxide/chemistry , Elastic Modulus , Hydrophobic and Hydrophilic Interactions , Materials Testing , Microscopy, Electron, Scanning , Particle Size , Surface Properties , Tensile Strength
19.
Luminescence ; 29(8): 1027-32, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24723449

ABSTRACT

A highly sensitive and convenient high-performance liquid chromatography technique coupled with chemiluminescence detection for the simultaneous determination butylated hydroquinone (TBHQ) and butylated hydroxyanisole (BHA) in oil is established. The detection is based on the inhibitory effect on the CL reaction between luminol and potassium ferricyanide in an alkaline medium. Samples were separated through a reverse-phase C18 column using a mobile phase of methanol and water (80: 20, v/v) at a flow rate of 0.5 mL/min. The effects of various parameters including mobile phase, flow rate and chemiluminescence regent were studied. Under optimum conditions, both TBHQ and BHA showed good linear relationships in the range 1 × 10(-7) -1 × 10(-5) g/mL with detection limits of 24 and 33 ng/mL, respectively. The proposed method is simple and sensitive, with low costs. The method was successfully applied for the quantification of TBHQ and BHA in sesame oil. The possible inhibition mechanism is also discussed briefly.


Subject(s)
Butylated Hydroxyanisole/analysis , Chromatography, High Pressure Liquid/methods , Hydroquinones/analysis , Luminescent Measurements/methods , Antioxidants/analysis , Antioxidants/chemistry , Butylated Hydroxyanisole/chemistry , Calibration , Food Analysis/methods , Hydroquinones/chemistry , Limit of Detection , Reproducibility of Results , Sensitivity and Specificity , Sesame Oil/analysis
20.
Mar Pollut Bull ; 83(1): 79-86, 2014 Jun 15.
Article in English | MEDLINE | ID: mdl-24775066

ABSTRACT

Microorganisms play an important role in the biodegradation of petroleum contaminants, which have attracted great concern due to their persistent toxicity and difficult biodegradation. In this paper, a novel hydrocarbon-degrading bacterium HZ01 was isolated from the crude oil-contaminated seawater at the Daya Bay, South China Sea, and identified as Achromobacter sp. Under the conditions of pH 7.0, NaCl 3% (w/v), temperature 28 °C and rotary speed 150 rpm, its degradability of the total n-alkanes reached up to 96.6% after 10 days of incubation for the evaporated diesel oil. Furthermore, Achromobacter sp. HZ01 could effectively utilize polycyclic aromatic hydrocarbons (PAHs) as its sole carbon source, and could remove anthracene, phenanthrene and pyrence about 29.8%, 50.6% and 38.4% respectively after 30 days of incubation. Therefore, Achromobacter sp. HZ01 may employed as an excellent degrader to develop one cost-effective and eco-friendly method for the bioremediation of marine environments polluted by crude oil.


Subject(s)
Achromobacter/isolation & purification , Petroleum Pollution/prevention & control , Petroleum/metabolism , Polycyclic Aromatic Hydrocarbons/metabolism , Seawater/microbiology , Achromobacter/metabolism , Alkanes/metabolism , Bays/microbiology , Biodegradation, Environmental , China , Petroleum/analysis , Petroleum/microbiology , Phenanthrenes/metabolism
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