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1.
J Environ Manage ; 347: 119076, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37748299

RESUMO

Excessive phosphorus (P) in surface water can lead to serious eutrophication and economic losses. Iron-based constructed wetland (CW) is considered as a promising solution to eliminate P effectively due to the advantage of low-cost. However, there is limited available information on the microbial removal mechanism of P in iron-based CW up to now. Therefore, CW with iron scrap was constructed to investigate the treatment performance and microbial removal mechanism in this study. Results showed that efficient and stable P removal (97.09 ± 1.90%) was achieved in iron scrap-based CW during the experiment period, which was attributed to the precipitation of iron and P and improved microbially mediated P removal. Metagenomic analysis showed that microbial diversity was enhanced and phosphate accumulating organisms (e.g., Dechloromonas and Tetrasphaera) were enriched in CW with iron scrap, which explained higher P removal reasonably. In addition, the abundance of genes involved in the P starvation (e.g., phoB), uptake and transport (e.g., pstB) were enhanced in iron scrap-based CW. Enrichment analysis demonstrated that phosphotransferase pathway was also significantly up-regulated in CW with iron scraps, indicating that the energy supply of microbial P removal was enhanced. These findings provide a better understanding of the microbial removal mechanism of P in iron-based CW.


Assuntos
Fontes de Energia Bioelétrica , Águas Residuárias , Áreas Alagadas , Ferro , Fósforo
2.
J Hazard Mater ; 443(Pt B): 130322, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36368068

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) pose a high risk to ecosystems owing to their adverse environmental effects. The use of biochar in constructed wetlands (CWs) to remove PAH has received increased interest, but is frequently challenging because of saturation adsorption. To enhance the microbial degradation, electron acceptors are provided. This study aimed to remove a representative PAH, benzofluoranthrene (BbF), using iron-modified biochar as a supplement to the CW substrate. Results revealed that iron-mediated biochar based CWs increased the removal of BbF by 20.4 % and ammonium by 25.6 %. The BbF retained in substrate with biochar (36.6 % higher content) and further removed with iron modification (40.6 % lower content). Iron-modified biochar increased dissolved organic carbon content, particularly low-aromaticity, and low-molecular-weight organic matters (25.7 % higher tryptophan-like material), which contributed to PAH degradation by microorganisms. Microbial analysis confirmed that iron-mediated biochar enriched the abundance of microbes (e.g., Cellulomonas, Actinotalea, and Sphingomonas) and key enzymes (e.g., catA, lipV, and sdhA) that are involved in PAH degradation. Higher proportion of iron-reducing bacteria (e. g., Thiobacillus, Rhodobacter) played a significant role in driving microbial iron cycle, which was beneficial for PAHs removal. Based on the results, we confirmed that the use of iron-modified biochar in CWs enhance PAH removal.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Áreas Alagadas , Matéria Orgânica Dissolvida , Ferro , Ecossistema , Carvão Vegetal/química , Hidrocarbonetos Policíclicos Aromáticos/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-35911137

RESUMO

Objective: There are variabilities in the distance between the tibial tuberosity and the trochlear groove. The knee angle needs to be considered when talking about patellofemoral instability. Methods: This retrospective study analyses the MRI images of knee angles from 0 and 30 degrees in the patella dislocation group (20 cases) and in the control group (20 cases) from Dec 2017 to Dec 2019. Two experienced orthopedic physicians separately measure the study with a blind experiment method. Results: The TT-TG data of the patella dislocation group and control group are 17.88 ± 3.40 mm and 13.31 ± 3.01 mm when the knee angle is 0, which indicates a difference with statistical significance (P < 0.01). The TT-TG data of the patella dislocation group and control group are 11.51 ± 3.60 mm and 7.40 ± 1.93 mm when the knee angle is at 30 degrees, indicating a statistically significant difference (P < 0.01). Also, the TT-TG data of both the patella dislocation group and control group have statistically significant differences within different knee angles of the same group (P < 0.01). The differences of TT-TG are 6.36 ± 2.43 mm and 5.92 ± 1.65 mm when the knee angle changes from 0 to 30, which shows no statistically significant difference (P > 0.01). Conclusion: This research initially obtained the relevant MRI data of the TT-TG distance from different knee angles between the Chinese patella dislocation patient group and control group. The study received a new criterion to evaluate the TT-TG of patients with patella dislocations when the knee angle is below 30 degrees. The knee flexion angles need to be considered to measure the TT-TG distance when comprehensively evaluating patellofemoral instability. The TT-TG distance gradually increases when the knee changes from flexion to extension. The difference of the TT-TG distances shows no statistically significant difference.

4.
Nanotechnology ; 30(29): 295301, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30917350

RESUMO

Layered semiconductors such as transition metal dichalcogenides (TMDs) with proper bandgaps complement the zero-bandgap drawback of graphene, demonstrating great potential for post-silicon complementary metal-oxide-semiconductor technology. Among the TMD family, molybdenum disulfide (MoS2) is highly attractive for its atomically thin body, large bandgap and decent mechanical and chemical stability. However, current nanofabrication techniques hardly satisfy the requirements of short channel and convenient preparation simultaneously. Here, we demonstrate a simple and effective approach to fabricate short channel chemical vapor deposition (CVD) monolayer MoS2 field-effect transistors (FET) with channel length down to 20 nm. Electron-beam lithography based on high-resolution negative-tone hydrogen silsesquioxane electron resists were applied to create 20 nm wide SiO x lines, defining the short channel length. The 20 nm MoS2 FET displays ON-sate current in excess of 100 µA µm-1. The corresponding current ON/OFF ratio at room temperature reaches 105. We carefully studied the short channel effect of as-fabricated MoS2 FETs. Combining with the large-scale growth of CVD method, our results will pave a way for short channel device applications based on atomically thin two-dimensional semiconductors.

5.
Tumour Biol ; 39(4): 1010428317697555, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28443459

RESUMO

Astragaloside IV, the active component of Astragalus membranaceus, exhibits diverse biological roles including the anti-tumor activity. In this study, we evaluated the chemosensitive role of astragaloside IV in non-small cell lung cancer cells. Cell Counting Kit-8 analysis was performed to determine cell viability. Real-time polymerase chain reaction and western blot were used to measure the messenger RNA and protein expression. Results showed that astragaloside IV treatment could suppress the proliferation of non-small cell lung cancer cells. In addition, combined treatment with astragaloside IV remarkably enhanced the chemosensitivity to gefitinib in three non-small cell lung cancer cell lines including NCI-H1299, HCC827, and A549. Furthermore, compared with gefitinib-treated cells, the messenger RNA expression of SIRT6 was obviously increased in non-small cell lung cancer cells treated with gefitinib combined with astragaloside IV. In addition, downregulation of SIRT6 was accomplished using small interference RNA technology. As a result, SIRT6 inhibition abolished the sensitization role of astragaloside IV in non-small cell lung cancer cells. Taken together, these data demonstrated that astragaloside IV sensitized tumor cells to gefitinib via regulation of SIRT6, suggesting that astragaloside IV may serve as potential therapeutic approach for lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quinazolinas/administração & dosagem , Saponinas/administração & dosagem , Sirtuínas/biossíntese , Triterpenos/administração & dosagem , Células A549 , Apoptose/efeitos dos fármacos , Astragalus propinquus/química , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Gefitinibe , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sirtuínas/genética
6.
J Toxicol Sci ; 41(3): 371-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27193729

RESUMO

4-nitrophenol (PNP) is generally regarded as a diesel exhaust particle (DEP). Arginine plays an important role as a new feed additive, possessing highly efficient antioxidant activities. Here we investigated the effects of dietary supplementation with arginine against ovarian damage induced by PNP in rats. A total of thirty-two female rats postnatal day 28 (PND 28) were randomly divided into four groups. Two groups were fed with basal diet or 13 g/kg arginine in diet for 4 weeks, respectively; the other two groups were given PNP (100 mg/kg b.w.) daily by subcutaneous injection for 2 weeks following pretreatment with either basal diet or arginine diet for 2 weeks. The values of body weight gain (BWG), average daily gain (ADG) and percentage weight gain (PWG) upon PNP treatment were significantly reduced than those in other groups. The relative liver weight in the PNP group was significantly decreased compared with the control group. Treatment with PNP significant reduced the number of corpora lutea, although serum 17ß-estradiol (E2) and progesterone (P4) concentrations were unchanged. The morphology of the ovaries in PNP-treated rats displayed necrosis, follicular deformation and granulosa cells irregular arrangement. Moreover, exposure to PNP enhanced production of malondialdehyde (MDA) and hydrogen peroxide (H2O2), and decreased the activities of total superoxide dismutase (T-SOD) and catalase (CAT), and the co-administration of arginine can attenuate the oxidative stress caused by PNP. These results suggest that arginine may have a protective effect against ovarian damage induced by PNP owing to its antioxidant capacity effect.


Assuntos
Antioxidantes/farmacologia , Arginina/farmacologia , Nitrofenóis/toxicidade , Ovário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Catalase/sangue , Citoproteção , Estradiol/sangue , Feminino , Peróxido de Hidrogênio/sangue , Malondialdeído/sangue , Necrose , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Ovário/metabolismo , Ovário/patologia , Progesterona/sangue , Ratos Sprague-Dawley , Superóxido Dismutase/sangue
7.
Oxid Med Cell Longev ; 2013: 692302, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24381717

RESUMO

Safflower yellow (SY) is the safflower extract and is the one of traditional Chinese medicine. The aim of the present work was to investigate the effect of SY on spinal cord ischemia reperfusion injury (SCIRI) in rabbits. The models of spinal cord ischemia reperfusion (SI/R) were constructed, and the degree of the post-ischemic injury was assessed by means of the neurological deficit scores and plasma levels of lipid peroxidation reactioin and neuronal morphologic changes. SCIRI remarkably affected the functional activities of the hind limbs and activated lipid peroxidation reaction. SY could attenuate apoptosis and SCIRI by enhancing Bcl-2 expression and inhibiting Bax and caspase-3 activation.


Assuntos
Chalcona/análogos & derivados , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Isquemia do Cordão Espinal/complicações , Isquemia do Cordão Espinal/tratamento farmacológico , Animais , Células do Corno Anterior/efeitos dos fármacos , Células do Corno Anterior/enzimologia , Células do Corno Anterior/patologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Forma Celular/efeitos dos fármacos , Chalcona/farmacologia , Chalcona/uso terapêutico , Membro Posterior/efeitos dos fármacos , Membro Posterior/fisiopatologia , Marcação In Situ das Extremidades Cortadas , Interleucina-8/sangue , Masculino , Malondialdeído/metabolismo , Fitoterapia , Coelhos , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/enzimologia , Isquemia do Cordão Espinal/sangue , Isquemia do Cordão Espinal/enzimologia , Superóxido Dismutase/metabolismo , Fatores de Tempo , Sinais Vitais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
8.
Neurotoxicology ; 33(5): 1230-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22824511

RESUMO

Many epidemiological studies and in vitro experiments have found that chronic arsenic exposure may influence memory formation. The goal of this study was to create an animal model of memory impairment induced by chronic arsenite exposure and to study the underlying mechanisms. Sixty male Sprague-Dawley (SD) male rats were randomly divided into a control group, a low-dose sodium arsenite exposure group and a high-dose sodium arsenite exposure group. Sodium arsenite was administered by adding it to drinking water for 3 months. Then, the spatial memory of the rats was examined with Morris water maze and Y maze. The concentration of arsenic in the blood and the brain was determined by an atomic fluorescence absorption spectrometer. The ultra-structure of hippocampal neurons was observed by an electron microscope. Timm staining was used for observing mossy fibers. We found that the concentration of arsenic in the blood and the brain increased in a dose-response manner (P<0.05). The performance of rats in the arsenite exposed group (15 mg/kg) was significantly impaired in the Morris water maze and Y maze tasks than those in the control group (P<0.05). Sodium arsenite exposure resulted in abnormal structural changes in the myelin sheaths of nerve fibers and decreases in the terminals of mossy fibers. Together, chronic sodium arsenite exposure through drinking water results in detrimental changes in the neuronal synapses, which may contribute to the arsenite-induced impairment of spatial memory.


Assuntos
Intoxicação por Arsênico/complicações , Hipocampo/patologia , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Neurônios/patologia , Sinapses/patologia , Análise de Variância , Animais , Intoxicação por Arsênico/etiologia , Arsenitos/metabolismo , Arsenitos/toxicidade , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Fibras Musgosas Hipocampais/patologia , Fibras Musgosas Hipocampais/ultraestrutura , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Comportamento Espacial/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura , Fatores de Tempo
9.
ACS Appl Mater Interfaces ; 3(9): 3308-15, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21870870

RESUMO

In this paper, highly selective core-shell molecularly imprinted polymers (MIPs) of tadalafil on the surface of magnetic nanoparticles (MNPs) were prepared. Three widely used functional monomers 2-(trifluoromethyl) acrylic acid (TFMAA), acrylic acid (AA), and methacrylic acid (MAA) were compared theoretically as the candidates for MIP preparation. MIP-coated magnetic nanoparticles (MIP-coated MNPs) showed large adsorption capacity, high recognition ability, and fast binding kinetics for tadalafil. Furthermore, because of the good magnetic properties, MIP-coated MNPs can achieve rapid and efficient separation with an external magnetic field simply. The resulting MIP-coated MNPs were used as dispersive solid-phase extraction (DSPE) materials coupled with HPLC-UV for the selective extraction and detection of tadalafil from medicines (herbal sexual health products). Encouraging results were obtained. The amounts of tadalafil that were detected from the herbal sexual health product was 43.46 nmol g(-1), and the recoveries were in the range of 87.36-90.93% with the RSD < 6.55%.


Assuntos
Carbolinas/química , Medicamentos de Ervas Chinesas/química , Nanopartículas de Magnetita/química , Impressão Molecular/métodos , Polímeros/química , Acrilatos/química , Adsorção , Carbolinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Metacrilatos/química , Extração em Fase Sólida/métodos , Tadalafila
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