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1.
EMBO J ; 42(20): e113743, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37661833

RESUMEN

Mitochondria play essential roles in cancer cell adaptation to hypoxia, but the underlying mechanisms remain elusive. Through mitochondrial proteomic profiling, we here find that the prolyl hydroxylase EglN1 (PHD2) accumulates on mitochondria under hypoxia. EglN1 substrate-binding region in the ß2ß3 loop is responsible for its mitochondrial translocation and contributes to breast tumor growth. Furthermore, we identify AMP-activated protein kinase alpha (AMPKα) as an EglN1 substrate on mitochondria. The EglN1-AMPKα interaction is essential for their mutual mitochondrial translocation. After EglN1 prolyl-hydroxylates AMPKα under normoxia, they rapidly dissociate following prolyl-hydroxylation, leading to their immediate release from mitochondria. In contrast, hypoxia results in constant EglN1-AMPKα interaction and their accumulation on mitochondria, leading to the formation of a Ca2+ /calmodulin-dependent protein kinase 2 (CaMKK2)-EglN1-AMPKα complex to activate AMPKα phosphorylation, ensuring metabolic homeostasis and breast tumor growth. Our findings identify EglN1 as an oxygen-sensitive metabolic checkpoint signaling hypoxic stress to mitochondria through its ß2ß3 loop region, suggesting a potential therapeutic target for breast cancer.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Neoplasias de la Mama , Femenino , Humanos , Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Hipoxia , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Mitocondrias/metabolismo , Proteómica
2.
Small ; : e2400288, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593337

RESUMEN

Capacitive deionization for selective separation of ions is rarely reported since it relies on the electrostatic attraction of oppositely charged ions with no capability to distinguish ions of different valent states. Using molecular dynamic simulation, a screening process identified a hybrid material known as AC/PTh, which consists of activated carbon with a thin layer of polythiophene (PTh) coating. By utilizing AC/PTh as electrode material implementing the short-circuit cycle (SCC) mode in flow-electrode capacitive deionization (FCDI), selective separation of mono-/divalent ions can be realized via precise control of dynamic adsorption and desorption of mono-/divalent ions at a particular surface. Specifically, AC/PTh shows strong interaction with divalent ions but weak interaction with monovalent ions, the distribution of divalent ions can be enriched in the electric double layer after a couple of adsorption-desorption cycles. At Cu2+/Na+ molar ratio of 1:40, selectivity toward divalent ions can reach up to 110.3 in FCDI SCC mode at 1.0 V. This work presents a promising strategy for separating ions of different valence states in a continuously operated FCDI device.

3.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38474944

RESUMEN

In this paper, we introduce a novel panoptic segmentation method called the Mask-Pyramid Network. Existing Mask RCNN-based methods first generate a large number of box proposals and then filter them at each feature level, which requires a lot of computational resources, while most of the box proposals are suppressed and discarded in the Non-Maximum Suppression process. Additionally, for panoptic segmentation, it is a problem to properly fuse the semantic segmentation results with the Mask RCNN-produced instance segmentation results. To address these issues, we propose a new mask pyramid mechanism to distinguish objects and generate much fewer proposals by referring to existing segmented masks, so as to reduce computing resource consumption. The Mask-Pyramid Network generates object proposals and predicts masks from larger to smaller sizes. It records the pixel area occupied by the larger object masks, and then only generates proposals on the unoccupied areas. Each object mask is represented as a H × W × 1 logit, which fits well in format with the semantic segmentation logits. By applying SoftMax to the concatenated semantic and instance segmentation logits, it is easy and natural to fuse both segmentation results. We empirically demonstrate that the proposed Mask-Pyramid Network achieves comparable accuracy performance on the Cityscapes and COCO datasets. Furthermore, we demonstrate the computational efficiency of the proposed method and obtain competitive results.

4.
Telemed J E Health ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38938217

RESUMEN

Purpose: With the rapid advancement of technology, online health care services are becoming increasingly prominent. This study aims to investigate medical students' perceptions, attitudes, and readiness to adopt online health care services. Methods: Based on a literature review, this study constructed a conceptual model describing the relationships among medical students' perception, personality traits, and usage intention, grounded in the Technology Acceptance Model and Technology Readiness Index (TRI). The data for this study were collected from January to February 2023 through a questionnaire survey at Wenzhou Medical University, China. The proposed hypotheses were tested using structural equation modeling through AMOS software. Results: Out of the 340 respondents, 281 (82.6%) validly responded. Among these, 58.4% of medical students agreed and strongly agreed with the intention to become an online doctor. Within the TRI's motivational factors, optimism positively and significantly affected perceived usefulness (PU) and perceived ease of use (PEOU). Innovativeness also significantly enhanced PEOU. Among the inhibitory factors, insecurity was found to have a negative and statistically significant influence on PU. The rest of the dimensions did not have a significant effect on either PU or PEOU. Importantly, both PU and PEOU demonstrated a direct and substantial effect on usage intention. Conclusions: This study emphasizes the significance of comprehending medical students' readiness to adopt the role of online doctors in shaping the future of health care. By equipping medical students with the necessary skills and competencies, health care institutions can effectively leverage the full potential of online health care services while ensuring the provision of high-quality, accessible, and patient-centered care in the digital era.

5.
Molecules ; 28(19)2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37836616

RESUMEN

In the healing of wounds, human-like collagen (hCol) is essential. However, collagen-based composite dressings have poor stability in vivo, which severely limits their current therapeutic potential. Based on the above, we have developed a recombinant fusion protein named hCol-ELP, which consists of hCol and an elastin-like peptide (ELP). Then, we examined the physicochemical and biological properties of hCol-ELP. The results indicated that the stability of the hCol-ELP fusion protein exhibited a more compact and homogeneous lamellar microstructure along with collagen properties, it was found to be significantly superior to the stability of free hCol. The compound hCol-ELP demonstrated a remarkable capacity to induce the proliferation and migration of mouse embryo fibroblast cells (NIH/3T3), as well as enhance collagen synthesis in human skin fibroblasts (HSF) when tested in vitro. In vivo, hCol-ELP demonstrated significant enhancements in healing rate and a reduction in the time required for scab removal, thereby exhibiting a scar-free healing effect. The findings provide a crucial theoretical foundation for the implementation of an hCol-ELP protein dressing in fields associated with the healing of traumatic injuries.


Asunto(s)
Elastina , Péptidos , Ratones , Animales , Humanos , Elastina/química , Péptidos/farmacología , Péptidos/química , Colágeno/química , Cicatrización de Heridas , Proteínas Recombinantes de Fusión/metabolismo
6.
Langmuir ; 38(40): 12263-12272, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36177722

RESUMEN

Both electrical conductivity and surface wettability are required for the selection of active carbon materials in flow-electrode capacitive deionization, while a trade-off exists between these two properties. In this work, a hybrid material with a thin layer of polyaniline (PANI) coating on activated carbon (AC/PANI) was successfully developed to retain excellent electrical conductivity and acquire good surface wettability. By adjusting the dosage of initiator, AC/PANI composites with different loading fractions of PANI were obtained. The electrochemical testing demonstrated that the AC/PANI composites have higher specific capacitance and lower ion diffusion resistance compared to pure AC, resulting in better desalinization performance. Specifically, with a feed concentration of 1600 mg/L, excellent adsorption capacity and high charge efficiency can be simultaneously achieved at 13.51 mg/g and 92.21%, respectively. Benefiting from the formation of a continuous electrical percolation network and reduced solid/liquid interfacial transport resistance, a 39% enhancement of average salt adsorption rate (from 0.54 to 0.75 µmol/min/cm2) was obtained.

7.
Environ Sci Technol ; 56(17): 12494-12505, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36006007

RESUMEN

Neonicotinoid insecticides have attracted worldwide attention due to their ubiquitous occurrence and detrimental effects on aquatic organisms, yet their impacts on fish reproduction during long-term exposure remain unknown. Here, zebrafish (F0) were exposed to a neonicotinoid, acetamiprid, at 0.19-1637 µg/L for 154 d. Accumulation and biotransformation of acetamiprid were observed in adult fish, and the parent compound and its metabolite (acetamiprid-N-desmethyl) were transferred to their offspring. Acetamiprid caused slight survival reduction and significant feminization in F0 fish even at the lowest concentration. Hormone levels in F0 fish were remarkedly altered, that is, gonad 17ß-estradiol (E2) significantly increased, while androstenedione decreased. The corresponding transcription of steroidogenic genes (ar, cyp19b, fshß, gnrh2, gnrh3, and lhß) were significantly upregulated in the brain and gonad of the females but downregulated in the males. The vtg1 gene expression in the liver of male fish was also upregulated. In addition to F0 fish, parental exposure to acetamiprid decreased hatchability and enhanced malformation of F1 embryos. Chronic exposure to acetamiprid at environmentally relevant concentrations altered hormone production and the related gene expression of the hypothalamic-pituitary-gonad (HPG) axis in a sex-dependent way, caused feminization and reproductive dysfunction in zebrafish, and impaired production and development of their offspring.


Asunto(s)
Insecticidas , Contaminantes Químicos del Agua , Animales , Bioacumulación , Femenino , Feminización/inducido químicamente , Feminización/metabolismo , Gónadas , Humanos , Insecticidas/metabolismo , Insecticidas/toxicidad , Masculino , Neonicotinoides/toxicidad , Reproducción , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/metabolismo
8.
BMC Pediatr ; 22(1): 25, 2022 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-34991497

RESUMEN

BACKGROUND: To reveal the changes of intestinal microbial abundance and composition, as well as the microbiota metabolic levels of bile acids and short chain fatty acids of healthy preschool children during their growth. METHODS: Feces of 120 healthy newborns and 150 healthy children aged 6 months to 6 years were collected. Then the composition of intestinal flora was analyzed by 16S rRNA, and the contents of bile acids and short chain fatty acids in feces were detected by LC-MS and GS methods, respectively. RESULTS: The composition and function of intestinal microflora were not stable in neonatal period but significantly improved at 6 months after birth, and gradually stabilized and tended to adult-like formation after 2-3 years old. The levels of short chain fatty acids and secondary bile acids were consistent with the development of gut microbiota. CONCLUSION: The age of 6 months may be a critical period for the development of intestinal microflora in children.


Asunto(s)
Microbioma Gastrointestinal , Adulto , Ácidos y Sales Biliares , Preescolar , Ácidos Grasos Volátiles/metabolismo , Heces , Humanos , Lactante , Recién Nacido , ARN Ribosómico 16S/genética
9.
Med Sci Monit ; 27: e928214, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33767128

RESUMEN

BACKGROUND Normal profiles of FBAs in healthy neonates and children in Kunming city and surrounding areas in China have not been previously determined. The objective of this study was to determine a developmental pattern of fecal bile acids (FBAs) in healthy neonates and children. MATERIAL AND METHODS A cross-sectional study was performed on 238 healthy neonates and children recruited in the First Affiliated Hospital of Kunming Medical University, China from October 2015 to September 2016. Secreted primary and secondary FBAs in fresh feces were quantitated by liquid chromatography mass spectrometry (LC-MS). Amounts of FBAs in feces were compared among various age groups. RESULTS Trace amounts of cholic acid and chenodiol acid of primary FBAs were detectable at day 3 after birth, with a significant increase from day 3 to day 7. The primary FBAs gradually decreased from day 25 to the age of 6 years old. In contrast, a significant amount of glycochenodeoxycholic acid was detected on day 3 but decreased to a trace amount by day 7 and onwards. Primary FBAs appeared to maintain a high level, accounting for 98% of total FBAs, with no significant changes from day 7 to day 25 after birth. They gradually decreased from 90% to 10% from age 6 months to 6 years old. While the secondary FBAs were barely detected in neonates, only accounting for 2% of total FBAs, they were gradually elevated to 90% of total FBAs from age 6 months to 6 years old. CONCLUSIONS The liver can effectively synthesize primary bile acids 7 days after birth, and fecal primary bile acids tend to be stable after the neonate stage. Secondary bile acids continuously increase along with the maturation of intestinal flora, which reaches a relatively stable level at around 3 years old.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Heces/química , Hígado/metabolismo , Ácidos y Sales Biliares/análisis , Niño , China , Cromatografía Liquida , Estudios Transversales , Femenino , Microbioma Gastrointestinal , Humanos , Recién Nacido , Masculino , Espectrometría de Masas
10.
Sensors (Basel) ; 21(14)2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-34300460

RESUMEN

Human action recognition methods in videos based on deep convolutional neural networks usually use random cropping or its variants for data augmentation. However, this traditional data augmentation approach may generate many non-informative samples (video patches covering only a small part of the foreground or only the background) that are not related to a specific action. These samples can be regarded as noisy samples with incorrect labels, which reduces the overall action recognition performance. In this paper, we attempt to mitigate the impact of noisy samples by proposing an Auto-augmented Siamese Neural Network (ASNet). In this framework, we propose backpropagating salient patches and randomly cropped samples in the same iteration to perform gradient compensation to alleviate the adverse gradient effects of non-informative samples. Salient patches refer to the samples containing critical information for human action recognition. The generation of salient patches is formulated as a Markov decision process, and a reinforcement learning agent called SPA (Salient Patch Agent) is introduced to extract patches in a weakly supervised manner without extra labels. Extensive experiments were conducted on two well-known datasets UCF-101 and HMDB-51 to verify the effectiveness of the proposed SPA and ASNet.


Asunto(s)
Redes Neurales de la Computación , Reconocimiento en Psicología , Actividades Humanas , Humanos , Aprendizaje , Cadenas de Markov
11.
Sensors (Basel) ; 21(7)2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805558

RESUMEN

Deep reinforcement learning (DRL) has been utilized in numerous computer vision tasks, such as object detection, autonomous driving, etc. However, relatively few DRL methods have been proposed in the area of image segmentation, particularly in left ventricle segmentation. Reinforcement learning-based methods in earlier works often rely on learning proper thresholds to perform segmentation, and the segmentation results are inaccurate due to the sensitivity of the threshold. To tackle this problem, a novel DRL agent is designed to imitate the human process to perform LV segmentation. For this purpose, we formulate the segmentation problem as a Markov decision process and innovatively optimize it through DRL. The proposed DRL agent consists of two neural networks, i.e., First-P-Net and Next-P-Net. The First-P-Net locates the initial edge point, and the Next-P-Net locates the remaining edge points successively and ultimately obtains a closed segmentation result. The experimental results show that the proposed model has outperformed the previous reinforcement learning methods and achieved comparable performances compared with deep learning baselines on two widely used LV endocardium segmentation datasets, namely Automated Cardiac Diagnosis Challenge (ACDC) 2017 dataset, and Sunnybrook 2009 dataset. Moreover, the proposed model achieves higher F-measure accuracy compared with deep learning methods when training with a very limited number of samples.


Asunto(s)
Ventrículos Cardíacos , Redes Neurales de la Computación , Corazón , Ventrículos Cardíacos/diagnóstico por imagen , Humanos
12.
Appl Microbiol Biotechnol ; 104(12): 5579-5591, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32303818

RESUMEN

Shewanella oneidensis MR-1 is a potent hydrogen producer in the deficiency of exogenous electron acceptors. The electron transfer pathway for hydrogen production remains unclear, although enzymes for hydrogen production have been identified in S. oneidensis MR-1. In this study, we investigated the electron transfer pathway from formate to hydrogen, given that formate is commonly a key chemical for bacterial hydrogen production. We revealed that two formate dehydrogenases FdhA1B1C1 and FdhA2B2C2, rather than FdnGHI, played a dominant role in formate-driven hydrogen production. Menaquinone was indispensable for the electron transfer from formate to hydrogen, which excluded the presence of formate hydrogen-lyase in S. oneidensis MR-1. A previously proposed formate dehydrogenase subunit HydC was identified as a menaquinone-binding subunit of [FeFe] hydrogenase HydAB, and the hydABC operon is conserved in bacteria living in diverse environments. A formate exporter FocA and transcriptional regulator FhlA were identified for their effect on formate metabolism and hydrogen production. FhlA positively affected the metabolism of formate and hydrogen by regulating the expression of fdhA2B2C2, fdnGHI, focA, and dld-II. Overall, the electron transfer pathway deciphered in this work will facilitate the improvement of biohydrogen production by S. oneidensis MR-1.Key Points• The electron transfer pathway from formate to hydrogen in MR-1 is deciphered.• Menaquinone is indispensable for hydrogen production.• A cytochrome b subunit transfers electrons from menaquinone to [FeFe] hydrogenase.


Asunto(s)
Formiatos/metabolismo , Hidrógeno/metabolismo , Oxidación-Reducción , Shewanella/enzimología , Transporte de Electrón , Formiato Deshidrogenasas/genética , Formiato Deshidrogenasas/metabolismo , Hidrogenasas/genética , Hidrogenasas/metabolismo , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Operón , Shewanella/genética , Vitamina K 2/metabolismo
13.
J Sep Sci ; 43(12): 2409-2418, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32170909

RESUMEN

Pesticides have posed significant threats to aquatic ecosystems, yet little is known about their transformation products. The challenge is to simultaneously analyze various pesticides and transformation products in water as they have distinct physicochemical properties. A mix-mode solid phase extraction method was established to simultaneously analyze current-use pesticides and their transformation products using a mixture of hydrophile-lipophile balance, weak anion, and cation exchange resins (2:1:1, w/w/w) in combination with high-performance liquid chromatography and tandem mass spectrometry for chemical quantification. Neutral, acidic, and alkaline methanol were used as the elution solvent. Box-Behnken design was applied to optimize extraction conditions. Optimal conditions were as follows: sorbent mass, 200 mg; volume of elution solvent, 5 mL × 3; pH 4. The method was validated for compounds at concentrations from 20 to 1000 ng/L in different types of water samples, with recovery being from 43.5 ± 3.1 to 141 ± 35%. Low method detection limits (0.02-5.6 ng/L) implied that the developed method was sensitive. Finally, the method was applied to monitor current-use pesticides and their transformation products in natural waters. Frequent detection of transformation products of pesticides indicated that their contribution to aquatic risk should not be ignored.

14.
Ecotoxicol Environ Saf ; 202: 110891, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32593097

RESUMEN

Organophosphate ester contaminants, including organophosphate pesticides (OPPs) and organophosphate flame retardants (OPFRs) are ubiquitous in surface water and pose a significant risk to aquatic organisms, thus it is important to develop effective methods for long-term monitoring of these emerging compounds. Polar organic chemical integrative sampler (POCIS) has become a promising monitoring tool for waterborne contaminants, yet recent studies found that the commonly used polyethersulfone (PES) membrane strongly sorbed some moderately hydrophobic compounds, resulting in long lag-phase for chemical accumulation in POCIS. In the present study, 0.45-µm nylon membranes was selected as POCIS diffusion-limiting membrane to design a new POCIS-Nylon configuration for analyzing moderately hydrophobic OPPs and OPFRs in water. The POCIS-Nylon had negligible lag-phase due to low sorption of OPPs and OPFRs to nylon membrane. Meanwhile, linear accumulation time and sensitivity for target contaminants using POCIS-Nylon retained similar to the traditional POCIS. Water velocity and chemical concentration had little impact on sampling rate (Rs), validating that the POCIS-Nylon was suitable for various water conditions. Finally, the occurrence of OPPs and OPFRs in urban waterways of Guangzhou, China was evaluated using the POCIS-Nylon with Rs values that were calibrated in the laboratory. The average concentration of OPPs was 4.97 ± 1.35 ng/L (range: 2.64 ± 1.28-6.54 ± 0.18 ng/L) and the average concentration of OPFRs was 400 ± 88 ng/L (range: 316 ± 24-615 ± 36 ng/L) across nine sampling sites. The present study provides a way to resolve the inherent challenge of accumulating hydrophobic substances by POCIS.


Asunto(s)
Monitoreo del Ambiente/métodos , Nylons/química , Contaminantes Químicos del Agua/análisis , Calibración , China , Retardadores de Llama/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos Orgánicos/química , Organofosfatos/análisis , Polímeros , Sulfonas
15.
Waste Manag Res ; 38(8): 903-910, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31918637

RESUMEN

In this study, the pyrolysis behaviour of nonmetal fraction of waste printed circuit boards (NMF-WPCBs) was studied based on five model-free methods and distributed activation energy model (DAEM). The possible decomposition mechanism was further probed using the Criado method. Thermogravimetric analysis indicated that the NMF-WPCBs pyrolysis process could be divided into three stages with temperatures of 37-330°C, 330-380°C and 380-1000°C. The mass loss at different heating rate was determined as 26.85-29.98%, 13.47-24.21% and 20.43-23.36% for these stages, respectively. The activation energy (Eα) from various model-free methods first increased with degree of conversion (α) increasing from 0.05 to 0.275, and then decreased beyond this range. The coefficient (R) from the Flynn-Wall-Ozawa (FWO) method was higher, and the resulting Eα fell into the range of 214.947-565.660 kJ mol-1. For the DAEM method, the average Eα value was determined as 337.044 kJ mol-1, comparable with 329.664 kJ mol-1 from the FWO method. The thermal decomposition kinetics of NMF-WPCBs could be better described by the second-order reaction.


Asunto(s)
Calefacción , Pirólisis , Cinética , Temperatura , Termogravimetría
16.
Waste Manag Res ; 38(11): 1251-1258, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31902310

RESUMEN

Advanced thermal treatment of electronic waste offers advantages of volume reduction and energy recovery. In this work, the pyrolysis behaviour of nonmetallic fractions of waste printed circuit boards was studied. The fate of a bromine and thermal decomposition pathway of nonmetallic fractions of waste printed circuit boards were further probed. The thermogravimetric analysis showed that the temperatures of maximum mass loss were located at 319°C and 361°C, with mass loss of 29.6% and 50.6%, respectively. The Fourier transform infrared Spectroscopy analysis revealed that the spectra at temperatures of 300°C-400°C were complicated with larger absorbance intensity. The nonmetallic fractions of waste printed circuit boards decomposed drastically and more evolved products were detected in the temperature range of 600°C-1000°C. The gas chromatography-mass spectrometry analysis indicated that various brominated derivates were generated in addition to small molecules, such as CH4, H2O and CO. The release intensity of CH4 and H2O increased with temperature increasing and reached maximum at 600°C-800°C and 400°C-600°C. More bromoethane (C2H5Br) was formed as compared with HBr and methyl bromide (CH3Br). The release intensity of bromopropane (C3H7Br) and bromoacetone (C3H5BrO) were comparable, although smaller than that of bromopropene (C3H5Br). More dibromophenol (C6H4Br2O) was released than that of bromophenol (C6H5BrO) in the thermal treatment. During the thermal process, part of the ether bonds first ruptured forming bisphenol A, propyl alcohol and tetrabromobisphenol A. Then, the tetrabromobisphenol A decomposed into C6H5BrO and HBr, which further reacted with small molecules forming brominated derivates. It implied debromination of raw nonmetallic fractions of waste printed circuit boards or pyrolysis products should be applied for its environmentally sound treating.


Asunto(s)
Bromo , Residuos Electrónicos , Residuos Electrónicos/análisis , Pirólisis , Reciclaje , Temperatura
17.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2266-2273, 2019 Jun.
Artículo en Zh | MEDLINE | ID: mdl-31359652

RESUMEN

A high-content GABA was found in Sojae Semen Praeparatum(SSP), which is a famous traditional Chinese medicine and officially listed in Chinese Pharmacopoeia. To screen out and identify GABA-producing microbes from samples at different time points during the fermenting process of SSP, traditional microbiological methods combined with molecular biological methods were used to study the predominant GABA-producing microorganisms existing in the fermenting process of SSP. This study would lay a foundation for further studying the processing mechanism of SSP. The fermenting process of SSP was based on Chinese Pharmacopoeia(2010 edition), and samples were taken at different time points during the fermenting process of SSP. The bacteria and fungi from samples at different time points in the fermenting process of SSP were cultured, isolated and purified by selective medium, and dominant strains were selected. The dominant bacteria were cultured in the designated liquid medium to prepare the fermentation broths, and GABA in the fermentation broth was qualitatively screened out by thin-layer chromatography. The microbial fermentation broth with GABA spots in the primary screening was quantitatively detected by online pre-column derivatization and high performance liquid chromatography established in our laboratory. GABA-producing microorganisms were screened out from predominant strains, and their GABA contents in fermentation broth were determined. The DNA sequences of GABA-producing bacteria and fungi were amplified using 16S rDNA and 18S rDNA sequences by PCR respectively. The amplified products were sequenced, and the sequencing results were identified through NCBI homology comparison. Molecular biological identification was made by phylogenetic tree constructed by MEGA 7.0 software. Through the homology comparison of NCBI and the construction of phylogenetic tree by MEGA 7.0 software, nine GABA-producing microorganisms were screened out and identified in this study. They were Bacillus subtilis, Enterococcus faecium, E. avium, Aspergillus tamarii, A. flavus, A. niger, Cladosporium tenuissimum, Penicillium citrinum and Phanerochaete sordida respectively. For the first time, nine GABA-producing microorganisms were screened out and identified in the samples at different time points during the fermenting process of SSP in this study. The results indicated that multiple predominant GABA-producing microorganisms exist in the fermenting process of SSP and may play an important role in the formation of GABA.


Asunto(s)
Bacterias/clasificación , Fermentación , Hongos/clasificación , Glycine max/microbiología , Ácido gamma-Aminobutírico/biosíntesis , Bacterias/metabolismo , Cromatografía Líquida de Alta Presión , Hongos/metabolismo , Filogenia
18.
J Sep Sci ; 41(2): 525-533, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29106043

RESUMEN

A new solid-phase adsorbent was synthesized for the simultaneous enrichment of multiple classes of trace insecticides (neonicotinoids, organophosphates, fiproles, and organochlorines) in water. The adsorbent was spherical with a diameter, surface area, average pore volume, and pore size of approximately 5 µm, 341 m2 /g, 0.092 m3 /g, and 2.22 nm, respectively. Extraction conditions were optimized, including water pH and the type and volume of the rinsing and eluting solvents. After extraction, target insecticides were analyzed by gas chromatography with mass spectrometry and high-performance liquid chromatography with tandem mass spectrometry. The recovery of neonicotinoids ranged from 63.0 to 124%, except for clothianidin (40.1-52.9%). Recoveries of organophosphates, fiproles, and organochlorines were in the ranges of 37.0-102, 64.0-101, and 42.0-69.3%, respectively. Relative standard deviations were <20% except for profenofos (5.1-30%) and method detection limits were 1.8-12.7 ng/L, suggesting that the precision and accuracy of the developed method were viable. At environmentally relevant concentrations, the new adsorbent achieved comparable recoveries of target insecticides to hydrophilic-lipophilic balance adsorbent while providing an additional advantage by further reducing matrix effects. Field water samples from the Pearl River in Guangzhou, China were analyzed, and the frequent detection of neonicotinoids raises concerns about their aquatic risk.

19.
J Sep Sci ; 39(22): 4439-4448, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27734586

RESUMEN

Molecularly imprinted polymers were synthesized using mixed tea saponins as a template and acrylamide-ß-cyclodextrin as a cofunctional monomer for the specific binding and purification of tea saponins from the defatted cake extract of Camellia oleifera. The adsorption properties of the prepared polymers were systematically evaluated including adsorption kinetics, adsorption isotherms, and selective recognition characteristics. It showed that the adsorption kinetics followed the pseudo first-order kinetic model (R2 = 0.995) with an equilibrium time of 3 h, adsorption isotherm data fitted well with the Langmuir-Freundlich model (R2 = 0.984) with an adsorption capacity of 14.23 mg/g. The relative selectivity coefficient (k´) in the presence of the analogues glycyrrhizic acid and glycyrrhetinic acid were 1.16 and 17.21, respectively. The performance of the molecularly imprinted polymers as solid-phase extraction materials was investigated and the results indicated that using acrylamide-ß-cyclodextrin as a cofunctional monomer improved both the adsorption capacity and active sites stability of the imprinted polymers. The solid-phase extraction using the polymers as packing materials was subsequently applied for the separation of tea saponins in raw C. oleifera press extract, and targets were obtained with a purity reaching 89%.


Asunto(s)
Camellia/química , Impresión Molecular , Saponinas/aislamiento & purificación , Té/química , Acrilamida/química , Adsorción , Polímeros , Extracción en Fase Sólida , beta-Ciclodextrinas/química
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(6): 517-21, 2016 Jun.
Artículo en Zh | MEDLINE | ID: mdl-27324540

RESUMEN

OBJECTIVE: To investigate the changes and clinical significance of biomarker fecal bile acids (BA) in children with Henoch-Schönlein purpura (HSP). METHODS: Nineteen children with HSP and twenty-seven healthy children were enrolled in this study. The stool samples were obtained at the acute and remission phases. Fecal BA levels were measured by high performance liquid chromatography mass spectrometry (HPLC-MS). RESULTS: The fecal cholic acid level in the HSP remission group was significantly higher than in the HSP acute group and the healthy control group (P<0.016). The fecal chenodeoxycholic acid level in the HSP remission group was significantly higher than in the healthy control group (P<0.016). The levels of fecal secondary colonic bile acids, deoxycholic acid and lithocholic acid, in the HSP acute and remission groups were significantly lower than in the healthy control group(P<0.05, P<0.016 respectively). No significant differences were found in the levels of fecal urosodeoxycholic acid among the three groups (P>0.05). CONCLUSIONS: Fecal secondary colonic bile acids, deoxycholic acid and lithocholic acid, are in decrease in children with HSP at the acute stage, which may be involved in the pathogenesis and treatment outcomes of HSP.


Asunto(s)
Ácidos y Sales Biliares/análisis , Heces/química , Vasculitis por IgA/diagnóstico , Biomarcadores/análisis , Niño , Femenino , Humanos , Vasculitis por IgA/terapia , Masculino
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