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1.
Sci Total Environ ; 867: 161593, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36642275

RESUMO

As a passivation material for heavy metals in-situ remediation, biochar (BC) has often been expected to maintain long-term adsorption performance for target pollutants. There is still lack of consensus about the impact of aging processes on biochar properties, particularly with respect to its long-term sorption performance. In this study, the changes to immobilization mechanisms as well as the speciation distribution of Cd(II) triggered by combined aging simulation (dry-wet, freeze-thaw cycle and oxidation treatment) on BC prepared under three levels of pyrolysis temperatures (300, 500 and 700 °C) were investigated. The results showed significant inhibition of aging on adsorption performance with the adsorptive capacity of BC300, BC500 and BC700 for Cd(II) decreased by 31.12 %, 50.63 % and 14.94 %, respectively. However, sequential extraction results indicated little influence of the aging process on the relative fractionation of Cd(II) speciation. The distribution of readily bioavailable, potentially bioavailable and non-bioavailable fractions of Cd(II) on BC showed only minimal changes post-aging. Overall, there was less Cd(II) sorption following aging, but the fractional availability (in relative terms) remained the same. Compared with 300 and 700 °C, the biochar prepared under 500 °C accounted the highest fraction of non-bioavailable Cd(II) (67.23 % of BC500, 59.17 % of Aged-500), and thus showed most promising for Cd(II) immobilization. This study has important practical significance for the long-term application of biochar in real environment.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Adsorção , Carvão Vegetal , Poluentes do Solo/análise , Solo
2.
Food Chem ; 391: 133224, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35623284

RESUMO

The properties of nutraceutical-loaded biopolymer nanoparticles fabricated by antisolvent co-precipitation (ASCP) and precipitation (ASP) were compared. Curcumin-loaded zein-tea saponin nanoparticles were fabricated using both methods and then their structural and physicochemical properties were characterized. The diameter of the nanoparticles prepared by ASCP were smaller (120-130 nm) than those prepared by ASP (140-160 nm). The encapsulation efficiency of the ASCP-nanoparticles (80.0%) was higher than the ASP-ones (71.0%) at a zein-to-curcumin mass ratio of 3:1, which was also higher than previous studies. The storage and light stability of curcumin was higher in zein-saponin nanoparticles than in zein nanoparticles. All nanoparticles had good water dispersibility after freeze-drying and rehydration. This study shows that nanoparticles produced by antisolvent co-precipitation have superior properties to those produced by antisolvent precipitation. The co-precipitation method leads to a higher encapsulation efficiency, smaller particle size, and greater storage stability, which may be advantageous for some applications.


Assuntos
Curcumina , Nanopartículas , Saponinas , Zeína , Curcumina/química , Nanopartículas/química , Tamanho da Partícula , Chá , Zeína/química
3.
Chemosphere ; 296: 134051, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35216977

RESUMO

As an in-situ immobilization material for heavy metals, biochar can exist in the environment for thousands of years, while whether the natural aging would affect its heavy metals adsorption performance still remains unclear. Therefore, the coffee grounds biochar (CGB) was prepared under different pyrolysis temperatures (300, 500 and 700 °C) in this study, and the simulated artificial aging treatment was carried out to investigate the effects of pyrolysis temperature and aging treatment on Cd2+ and Zn2+ (both separate and combined conditions) adsorption performance of CGB. The result revealed that Fresh-CGB adsorption performance increased with increasing pyrolysis temperature, while the relationship was not so clear with Aged-CGB where adsorption performance peaked at medium pyrolysis temperature (500 °C) but reduced again as pyrolysis temperature increased to 700 °C. The changes of Aged-CGB adsorption performance for Cd2+ and Zn2+ represented the long-term performance of naturally aging biochar in environment, and a mid-range pyrolysis temperature would seem most appropriate for long-term application of biochar. The X-ray Diffraction (XRD) result revealed that the degree of graphitization of CGB increased with increasing pyrolysis temperature, which represents a stronger environmental stability as the weight loss of CGB300, CGB500 and CGB700 after aging treatment was 2.38%, 0.66%, and 0%, respectively. The EDS and FTIR results suggested that ion-exchange and complexation between CGB/Aged-CGB with Cd2+/Zn2+ played a dominant role in adsorption processes. In addition, the selectivity for Cd2+ was significantly improved after the aging treatment. This is desirable given the stronger toxicity of Cd2+ relative to Zn2+. In general, this study provides new insights into the practical application of biochar from the perspective of long-term effects.


Assuntos
Metais Pesados , Pirólise , Adsorção , Cádmio , Carvão Vegetal , Café , Metais Pesados/análise , Temperatura , Zinco
4.
Artigo em Inglês | MEDLINE | ID: mdl-32182762

RESUMO

Heavy metal pollution in the river environment has been a source of widespread interest due to potential threats to human health and ecosystem security. Many studies have looked at heavy metal pollution in the context of single source-pathway-receptor relationships, however few have sought to understand pollution from a more wholistic multi-media perspective. To investigate potential risks in a more wholistic way, concentrations of six heavy metals (Cd, Cr, Ni, Cu, Zn and Pb) were detected in multi-media (water, sediment and riparian soil) collected from 14 sampling sites in the main stream of the Songhua River. Chemical analyses indicated that the average concentration of heavy metals in water followed: Zn > Cr > Cu > Pb > Ni > Cd, with a different trend observed in sediments and riparian soil: Zn > Cr > Ni > Pb > Cu > Cd. The potential risk was evaluated using the heavy metal pollution index (HPI), Nemerow pollution index (PN), hazard index (HI) and carcinogenic risk (CR) metrics. Results showed that all HPI values were lower than the critical level of 100 indicating that the levels of these targeted heavy metals were within drinking water safety limits. The PN indicated that both sediment (2.64) and soil (2.95) could be considered "moderately polluted", with Cd and Zn providing the most significant contributions. A human health risk assessment suggested that the non-carcinogenic risks were within acceptable levels (HI < 1), as was the cancer risk associated with dermal adsorption (CR <10-6). However, the CR associated with ingestion exposure (4.58 × 10-6) exceeded the cancer risk threshold (10-6) indicative of elevated cancer incidence in exposed populations. Health-risk estimates were primarily associated with Cd in the Songhua River. Source apportionment was informed by Pearson correlation analysis coupled with principal component analysis (PCA) which indicated that Cu was mainly derived from natural (geogenic) sources; Cr and Ni were associated with industrial emissions; Pb might be derived from agricultural and transportation sources; Zn might be from industrial, agricultural activities and transportation; while Cd is likely from industrial and agricultural emissions. The source apportionment information could provide the basis for a risk-management strategy focused on reducing Cd and Zn emissions to the riverine environment. Results from this study will provide the scientific knowledge that is needed for measuring and controlling heavy metals sources and pollution characteristics, and identifying the potential cancer risk with different exposure pathways, as well as making effective environmental management policies at catchment or regional scales.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Metais Pesados , Poluentes do Solo , China , Ecossistema , Monitoramento Ambiental , Humanos , Medição de Risco , Rios/química , Solo
5.
Artigo em Chinês | WPRIM | ID: wpr-509108

RESUMO

In order to optimize the curriculum structure, improve the quality of the traditional med-ical curriculum which separates the theory teaching and clinical teaching in medical education; give full play to the advantages of the multiple disciplines application to guide students to establish a holistic view of medicine; cultivate students'! independent thinking and team cooperation ability, we explore the reform model of the pediatric teaching courses from the following five aspects:curriculum design, class hour arran-gement, teaching team building, teaching carrier production and application of problem-based learning (PBL) teaching method. Preliminarily establish the teaching mode in multi disciplines integration which is characterized by taking a certain symptom or sign as leading clue.

6.
Int J Mol Med ; 29(4): 711-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22246209

RESUMO

Glyceollins, produced to induce disease resistance responses against specific species, such as an incompatible pathogen Phytophthora sojae in soybeans, have the potential to exhibit anti-inflammatory activity in RAW 264.7 cells. To investigate the anti-inflammatory effects of elicited glyceollins via a signaling pathway, we studied the glyceollin signaling pathway using several assays including RNA and protein expression levels. We found that soybean glyceollins significantly reduced LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, as well as the expression of inducible ΝΟ synthase (iNOS) and cyclooxygenase-2 (COX-2) via the suppression of NF-κB activation. Glyceollins also inhibited the phosphorylation of IκBα kinase (IKK), the degradation of IκBα, and the formation of NF-κB-DNA binding complex in a dose-dependent manner. Furthermore, they inhibited pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-18, but increased the generation of the anti-inflammatory cytokine IL-10. Collectively, the present data show that glyceollins elicit potential anti-inflammatory effects by suppressing the NF-κB signaling pathway in RAW 264.7 cells.


Assuntos
Ciclo-Oxigenase 2/genética , Glycine max/química , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Extratos Vegetais/farmacologia , Pterocarpanos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Resistência à Doença , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/metabolismo , Proteínas I-kappa B/metabolismo , Interleucina-18/antagonistas & inibidores , Interleucina-18/metabolismo , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/metabolismo , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo
7.
Zhongguo Zhen Jiu ; 31(4): 349-52, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21528603

RESUMO

OBJECTIVE: To prove analgesia and sedative effect of adjuvant anesthesia with magnetic auricular point-sticking on abdominal gynecological operation and its effect on postoperative recovery of body function. METHODS: Ninety-two patients with abdominal gynecological operation were randomly divided into 3 groups. The auricular point-sticking group (APS group, n=31) was pasted and pressed by plasters with magnetic beads at bilateral Shenmen, Pizhixia (subcortex), Zigong (uterus) and Penqiang (pelvic cavity), etc. the night before operation. The placebo group (n=31) was pasted by plasters without magnetic beads. The blank group (n=30) was given no intervention. The mental and gastrointestinal functional changes before and 3 days after the operation were observed. RESULTS: As compared with those in the control group and the blank group, the postoperative score of Self rating Anxiety Scale (SAS) was less (25.5 +/- 0.81 vs. 28.9 +/- 3.19, 28.3 +/- 2.36, both P < 0.01), with lower-dose of Innovar [(2.5 + 1.1) mL vs. (3.4 + 1.8) mL, (3.2 + 1.6) mL, both P < 0.05], earlier exsufflation after the operation [(34.2 + 12.1) h vs. (46.3 + 10.9) h, (43.2 + 14.8) h, both P < 0.01] and higher level serum of beta-endorphin before and after the operation in the APS group (all P < 0.05). CONCLUSION: The magnetic auricular point-sticking has sedative, analgesic and function-regulating effects on the abdominal gynecological operation.


Assuntos
Analgesia por Acupuntura , Acupuntura Auricular , Adjuvantes Anestésicos/administração & dosagem , Dor Pós-Operatória/terapia , Recuperação de Função Fisiológica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/fisiopatologia , Período Pós-Operatório , Adulto Jovem
8.
Zhong Xi Yi Jie He Xue Bao ; 3(5): 355-8, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16159566

RESUMO

OBJECTIVE: To explore the circadian distribution of premature ventricular contractions (PVCs) in patients with viral myocarditis (VM) according to the theory of chronomedicine in traditional Chinese medicine (TCM) in order to find out the scientific evidence for a reasonable administration time. METHODS: Two hundred and forty patients with VM were enrolled and electrocardiograms were examined for all by Holter monitor. The circadian distribution of PVCs was evaluated according to the theory of chronomedicine of TCM about time periods corresponding to five zang viscera. RESULTS: PVCs mostly happened in periods of 3:00-5:00, 5:00-7:00, 7:00-9:00 and 9:00-11:00, in which 5:00-7:00 was the most serious time. Less PVCs happened in periods of 17:00-19:00, 19:00-21:00 and 21:00-23:00. The frequency of PVCs in midnight also increased with aging. The time periods of the frequency peak of PVCs in patients with different syndromes were also different. In patients with syndrome of pathogenic heat invading heart (PHIH), the PVCs mostly appeared in midday. In patients with syndrome of flaring of fire due to yin-deficiency (FFYD), the PVCs were most serious in daytime and aggravated at noon. And in patients with syndrome of insufficiency of heart-qi and yang (IHQY), the PVCs mostly happened in early morning or midnight. CONCLUSION: There was a manifest regulation of the pathological circadian rhythm of PVCs in patients with VM. The circadian distributions of PVCs were variable in patients with different syndromes. Therefore the theory of chronomedicine of TCM may be used to guide the treatment based on syndrome differentiation.


Assuntos
Ritmo Circadiano , Diagnóstico Diferencial , Medicina Tradicional Chinesa , Miocardite/fisiopatologia , Complexos Ventriculares Prematuros/fisiopatologia , Adolescente , Adulto , Criança , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/complicações , Complexos Ventriculares Prematuros/etiologia
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