ABSTRACT
Increasing water pollution has imposed great threats to public health, and made efficient monitoring and remediation technologies critical to a clean environment. In this study, a versatile heterojunction of Au nanoparticles modified phosphorus doped carbon nitride (Au/P-CN) is designed and fabricated. The Au/P-CN heterostructure demonstrates improved light absorption, rapid separation of charge carriers, and improved electrical conductivity. Taking the toxic 4-chlorophenol (4-CP) as an example, an ultrasensitive photoelectrochemical (PEC) sensor is successfully demonstrated, exhibiting a wide linear range (0.1-52.1 µM), low detection limit (â¼0.02 µM), significant stability and selectivity, as well as reliable analysis in real samples. Moreover, efficient photocatalytic degradation with a high removing efficiency (â¼87%) toward 4-CP is also achieved, outperforming its counterpart of Au nanoparticles (NPs) modified graphitic carbon nitride (Au/g-CN, â¼59%). This work paves a new way for efficient and simultaneous detection and remediation of organic pollutants over versatile photoactive catalysts.
Subject(s)
Gold , Metal Nanoparticles , PhosphorusABSTRACT
Research interests have been recently thrust into the nonradical reactions in persulfate-based advanced oxidation processes (AOPs), whilst the underlying mechanism of the nonradical pathway remains ambiguous especially in metal-based AOPs systems. In this study, we investigated the reactivity of cuprous oxide (Cu2O) for activating peroxymonosulfate (PMS) to decompose diverse organic contaminants. Cu2O exhibited a strong catalytic dependence on the crystal morphology, and cubic Cu2O was more reactive than the octahedral and rhombic dodecahedral structures for catalytic degradation of bisphenol A with PMS. Chemical quenching tests, electron paramagnetic resonance (EPR), solvent exchange and selective oxidation experiment were corporately conducted to illustrate that Cu2O-catalyzed PMS did not produce free radicals or singlet oxygen. In contrast, a surface-confined metastable intermediate would be formed via outer-sphere interactions between PMS and Cu2O, which directly attacked the organic substrate. Such a reaction pathway is intrinsically distinct from the electron-shuttling regime in carbon (or noble metal)/persulfate systems via the conductive surface of the catalyst, and the outer-sphere interactions let the activated PMS demonstrate a higher oxidizing capacity toward organic contaminants. Therefore, this study dedicates to providing new insights into the copper-catalyzed AOPs and vital supplementary to the ongoing dialogue of the nonradical catalysis in persulfate-based oxidation.
ABSTRACT
In this study, biodegradable κ-carrageenan films containing 3% nanoclay and different amounts of rosemary extract (1, 2 and 3% v/v) were fabricated and their physical, thermal, and mechanical properties, as well as antimicrobial activity were examined. The film thickness did not change significantly by the addition of rosemary extract. UV light transmission value in the control film was 20.46%, while the value for the film with 3% v/v rosmary extract reduced to 0.13%. Elongation at break (EB%) and tensile strength (TS) of the carrageenan film without the extract were 19.07% and 15.96MPa, respectively, while after adding 3% v/v of rosemary extract, the EB and TS were increased to 27.17% and 30.77MPa, respectively. Incorporation of rosemary extract greatly reduced water vapor permeability (WVP) (5.27×10-10g/m·s·Pa in control film vs 2.14×10-10g/m·s·Pa in the film containing 3% v/v rosemary extract). More importantly, the carrageenan film with 3% extract displayed >99% inhibition against B. cereus, E. coli, P. aeruginosa, and S. aureus compared with the control film. The present study showed that rosemary extract is an excellent additive to enhance the mechanical strength and antibacterial activity of carrageenan films and can be used for active packing in food packing industry.
Subject(s)
Aluminum Silicates/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Carrageenan/chemistry , Nanocomposites/chemistry , Plant Extracts/chemistry , Rosmarinus/chemistry , Carrageenan/metabolism , Clay , Color , Mechanical Phenomena , Optical Phenomena , Permeability , SteamABSTRACT
Fatal familial insomnia (FFI) is an autosomal dominant prion disease clinically characterized by rapidly progressive insomnia, prominent autonomic alterations and behavioral disturbance. The D178N mutation of the prion protein gene (PRNP) on chromosome 20 in conjunction with methionine at codon 129 is a molecular feature. Although the neuropathological characteristics of FFI are well documented, the neuropathologic and pathogenic features of FFI patients remain poorly understood. Six brain regions of postmortem brains from 3 FFI patients were examined using immunohistochemistry, western blot analyses and quantitative real-time PCR. In all 3 brain specimens, reactive astrogliosis was found to be more severe in the thalamus than in the cortex regions. Western blot analyses showed that all three brains expressed PrP, but only 2 were associated with significantly weak proteinase K (PK) resistance. However, the conformational stabilities of PrPSc in the 3 FFI brains were significantly weaker than those presented in a G114V genetic Creutzfeldt-Jakob disease (gCJD) case. Immunohistochemistry and western blot analyses showed comparable amounts of neuron-specific enolase (NSE)-positive stained cells and NSE protein among the different regions in the three brains. In addition, the transcriptional levels of glial fibrillary acidic protein (GFAP) and NSE-specific mRNAs were coincident with the expression of these proteins. In conclusion, in the present study, we described the detailed regional neuropathology of FFI cases.
Subject(s)
Gyrus Cinguli/pathology , Insomnia, Fatal Familial/pathology , Prefrontal Cortex/pathology , Thalamus/pathology , Adult , Animals , Autopsy , Blotting, Western , Chromosomes, Human, Pair 20/genetics , Codon/genetics , Creutzfeldt-Jakob Syndrome/genetics , Creutzfeldt-Jakob Syndrome/pathology , Endopeptidase K/genetics , Endopeptidase K/metabolism , Female , Glial Fibrillary Acidic Protein/genetics , Glial Fibrillary Acidic Protein/metabolism , Gyrus Cinguli/metabolism , Humans , Immunohistochemistry , Insomnia, Fatal Familial/genetics , Male , Methionine/genetics , Methionine/metabolism , Mice , Mice, Inbred C57BL , Middle Aged , Mutation , Pedigree , Phosphopyruvate Hydratase/genetics , Phosphopyruvate Hydratase/metabolism , Prefrontal Cortex/metabolism , Prion Proteins , Prions/genetics , Prions/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Specimen Handling , Thalamus/metabolism , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
A sensitive and reliable assay has been developed to directly screen DNA-targeted anticancer drugs in vitro via using resonance light scattering (RLS) technique. The results of experiments displayed that the increment of RLS intensity was directly proportional to the antitumor effect of anticancer drugs. Through the RLS spectra, the activities of four drugs have been demonstrated as mitoxantrone (MIT)>epirarubicin (EPI)>daunorubicin (DAU)>adriamycin (ADM). However, to further verify the activities of the above four drugs, binding constant (k) for each of them has been calculated by RLS technique as follows: k(RLS) (MIT, 8.75 x 10(5) L mol(-1))>k(RLS) (EPI, 6.58 x 10(5) L mol(-1))>k(RLS) (DAU, 4.79 x 10(5) L mol(-1))>k(RLS) (ADM, 3.82 x 10(5) L mol(-1)). Also, this RLS assay result was validated by seasoned vitro screening methods for anticancer drugs. In all, the proposed RLS is not only a simple, sensitive, objective and straightforward method, but also it is an unprecedented assay for primarily screening DNA-targeted anticancer drugs.
Subject(s)
Antineoplastic Agents/analysis , Antineoplastic Agents/chemistry , Biosensing Techniques/methods , DNA, Neoplasm/analysis , DNA, Neoplasm/chemistry , Refractometry/methods , Spectrometry, Fluorescence/methods , Animals , Drug Delivery Systems/methods , Drug Evaluation, Preclinical/methods , Humans , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Barley straw, an agricultural waste, was chemically modified and evaluated for the removal of emulsified oils from aqueous solution. The chemical modification was performed using NaOH and a cationic surfactant, hexadecylpyridinium chloride monohydrate (CPC). The surface textural and chemical properties of the surfactant modified barley straw (BMBS) were characterized by N(2) adsorption, FT-IR, SEM and water soluble mineral content. The adsorption tests were carried out in batch adsorption system for removal of standard mineral oil (SMO) and canola oil (CO) from water. For both emulsified oils in wastewater, adsorption was found to be strongly related with solution pH. The isotherm study indicated that emulsified oil adsorption on BMBS could be fitted well with the Langmuir model other than Freundlich model. The maximum adsorption capacity for CO and SMO at 25 degrees C determined from the Langmuir isotherm is 613.3 and 584.2 mg g(-1), respectively. Desorption tests in water solution show that oil is strongly bonded with adsorbent and desorption is only about 1-2% in 24 h.
Subject(s)
Fatty Acids, Monounsaturated/isolation & purification , Hordeum/metabolism , Mineral Oil/isolation & purification , Surface-Active Agents/chemistry , Water Purification/methods , Adsorption , Biotechnology/methods , Cations , Cetylpyridinium/chemistry , Emulsifying Agents , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning/methods , Mineral Oil/analysis , Minerals/chemistry , Rapeseed Oil , Spectroscopy, Fourier Transform Infrared , Water/chemistryABSTRACT
Red mud (RM) is a by-product of bauxite processing via the Bayer process. Its disposal remains an issue of great importance with significant environmental concerns. In the past decades, a lot of research has been done to utilize red mud for environmental-benign applications such as a building material additive and for metal recovery. In recent years, red mud has also been explored for gas cleaning and wastewater treatment. In this paper, we review varying novel applications of red mud as a coagulant and adsorbent for water and gas treatment as well as catalyst for some industrial processes. The environmental compatibility of red mud is discussed. Some directions of future research are also proposed. Red mud presents a promising application in water treatment for removal of toxic heavy metal and metalloid ions, inorganic anions such as nitrate, fluoride, and phosphate, as well as organics including dyes, phenolic compounds and bacteria. In addition, red mud can also be employed as catalysts for hydrogenation, hydrodechlorination and hydrocarbon oxidation. Moreover, leaching and eco-toxicological tests indicate that red mud does not present high toxicity to the environment before or after reuse.
Subject(s)
Aluminum Oxide/chemistry , Coagulants/chemistry , Conservation of Natural Resources/methods , Industrial Waste , Refuse Disposal/methods , Adsorption , CatalysisABSTRACT
OBJECTIVE: To study the feasibility and validity of multi-modal serial therapy for primary liver cancer in senile patients. METHODS: 153 senile primary liver cancer patients (>or= 60 years) were given multi-modal serial therapy from June 1993 to December 2000. Hepatectomy was performed in 37, deep cryosurgery in 32 and non-operative therapy in 84 (intervention as chief therapy in 81, combined local and intervention therapy in 3). The multi-course intervention therapy was given postoperatively in hepatectomy and cryosurgery groups, while bioimmunotherapy and traditional Chinese medicine were used in all groups. RESULTS: The 1-, 3- and 5-year survival rates in the hepatectomy group were 78.4%, 46.4% and 35.7%, without operative mortality. The 1- and 3- and 5-year year survival rates in the cryosurgery group were 64.5%, 40.9% and 25.0% with mortality of 3.1%. Among patients with non-operative therapy, the 1- and 3- and 5-year year survival rates in intervention group were 47.5%, 23.5% and 4.3%. The operative mortality was 1.2%. The 3 patients who received combined local and intervention therapy have survived for 2.5, 3.8 and 7.1 years. CONCLUSION: Multi-modal serial therapy with surgical treatment as the chief means, being precise in the effect and good in safety, is feasible and valid for primary liver cancer in senile patients.
Subject(s)
Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic , Cryosurgery , Hepatectomy , Liver Neoplasms/therapy , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/pathology , Combined Modality Therapy , Feasibility Studies , Female , Humans , Infusions, Intra-Arterial , Liver Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Survival RateABSTRACT
OBJECTIVE: To discuss the methods and effects of serial therapies oriented by surgery in the treatment of primary large liver cancers. METHODS: From January 1993 to June 1999, 191 patients with large liver carcinoma were treated surgically. The size of tumors varied from 5.2 to 19.7 cm (mean 9.4 cm). Several types of liver resections were made in 121 patients and as a supplement, cryosurgery was carried out for the remaining 70 patients. Importable drug delivery system was instituted intraoperatively. Transcatheter arterial chemo-embolization (THP 30-60 mg, E-ADM 20-40 mg, CDDP 40-80 mg, MMC 10-20 mg, iodin oil 5-30 ml), percutaneous ethanol injection, bioimmunotherapy and traditional Chinese medicine were used pre- and post-operatively. CT angiography and CT during arterial portography were used to find satellite nodules. Early stage recurrences were predicted by AFPmRNA in peripheral blood. Child-Pugh's classification plus branch chain amino acid/aromatic amino acid ratio (BCAA/AAA) was adopted in evaluating pre-operative liver functions. RESULTS: Marked results were observed after serial treatments oriented by surgery. The 1-, 3- and 5-year survival rates in resection group were 75.8%, 45.6% and 30.4%, respectively. The 1- and 3-year survival rates in cryosurgery group were 63.2% and 37.0%. The operative mortality was 1.57%. Recurrence rates were 69.2% in AFPmRNA positive group and 33.3% in AFPmRNA negative group (P<0.05). The BCAA/AAA ratio was lower than 1.5 in two patients who died of hepatic failure after resection. CONCLUSIONS: Serial treatments with surgery as the chief modality gives satisfactory results in patients with large primary liver carcinoma. This regimen should be regarded as a main strategy to deal with large liver carcinoma. AFPmRNA in the peripheral blood, signifying a recurrence, may become a new clinical parameter. The BCAA/AAA ratio plus Child-Pugh's classification is able to evaluate more accurately liver function reserve before surgery.