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1.
Phytomedicine ; 120: 155032, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37611463

RESUMO

BACKGROUND: In recent years, Salvia miltiorrhiza and its active substances have remarkably progressed in treating central neurological disorders. Tanshinone IIA (TSA) is an active ingredient derived from the rhizome of Salvia miltiorrhiza that has been found to alleviate the symptoms of several psychiatric illnesses. Post-traumatic stress disorder (PTSD) is a mental disorder that results after experiencing a serious physical or psychological injury. The currently used drugs are not satisfactory for the treatment of PTSD. However, it has been reported that TSA can improve PTSD-like symptoms like learning and memory, cognitive disorder, and depression through multi-target regulation. PURPOSE: This paper discusses the ameliorative effects of TSA on PTSD-like symptoms and the possible mechanisms of action in terms of inhibition of neuronal apoptosis, anti-neuroinflammation, and anti-oxidative stress. Based on the pathological changes and clinical observations of PTSD, we hope to provide some reference for the clinical transformation of Chinese medicine in treating PTSD. METHODS: A large number of literatures on tanshinone in the treatment of neurological diseases and PTSD were retrieved from online electronic PubMed and Web of Science databases. CONCLUSION: TSA is a widely studied natural active ingredient against mental illness. This review will contribute to the future development of TSA as a new clinical candidate drug for improving PTSD-like symptoms.


Assuntos
Salvia miltiorrhiza , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Abietanos/farmacologia , Apoptose , Estresse Oxidativo
2.
Phytomedicine ; 116: 154898, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37247590

RESUMO

BACKGROUND: The accumulation of CD4+Foxp3+ regulatory T cells (Tregs) in the tumor microenvironment (TME) dampens anti-tumor immune responses and promotes tumor progression. Therefore, the elimination of Tregs has become a strategy to enhance the efficacy of tumor immunotherapy, although it is still a daunting challenge. Rhododendron brachypodum (R. brachypodum) is a perennial shrub mainly distributed in Southwestern China, whereas the chemical constituents in this plant remain elusive. PURPOSE: To identify small-molecule inhibitors of Tregs from R. brachypodum. METHODS: Meroterpenoids in R. brachypodum were isolated by column chromatography under the guidance of LCMS analyses. The structures of isolates were identified by spectroscopic data and quantum calculations. The activities of compounds were first evaluated on CD4+ T cell differentiation by flow cytometry in Th1, Th2, Th17, and Treg polarizing conditions, and then on CT26 and MC38 murine colorectal carcinoma cells-allografted mice models. The mechanism of action was first investigated by determining Foxp3 degradation in Jurkat T cells transfected with pLVX-TetOne-Puro-Foxp3-tGFP, and then through analyses of Foxp3 expression on several pre-transcriptional signaling molecules. RESULTS: Two new prenylated phenolic acids (1 and 2) and a chromane meroterpenoid, rubiginosin B (RGB, 3) were obtained from R. brachypodum. The structure of S-anthopogochromene C (1) was rectified according to the electronic circular dichroism (ECD) experiment, and rhodobrachypodic acid (2) was proposed as the precursor of RGB by photochemical transformation. In this investigation, we first found that RGB (3) selectively suppressed the de novo differentiation of TGFß-induced CD4+Foxp3+ regulatory T cells (iTregs), overcome the immunosuppressive TME, and consequently inhibited the growth of tumor in mouse models. The mechanistic study revealed that RGB could target calcineurin, inhibited the nuclear factor of activated T cells (NFAT) dephosphorylation, and down-regulated Foxp3 expression. The hypothetical binding modes of RGB with calcineurin were predicted by molecular docking, and the interactions were mainly hydrophobic effects and hydrogen bonds. CONCLUSION: These results suggest that RGB enhances anti-tumor immune responses by inhibiting Treg cell differentiation through calcineurin-NFAT signaling pathway, and therefore RGB or its analogs may be used as adjuvant agents meriting further investigation.


Assuntos
Neoplasias , Linfócitos T Reguladores , Camundongos , Animais , Calcineurina/metabolismo , Simulação de Acoplamento Molecular , Neoplasias/patologia , Diferenciação Celular , Transdução de Sinais , Ativação Linfocitária , Fatores de Transcrição Forkhead/metabolismo , Microambiente Tumoral
3.
Environ Technol ; 44(8): 1114-1124, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34704537

RESUMO

The microwave enhanced advanced oxidation process (MW-AOP) has been applied to pre-treat different sludge types and high solids content. Secondary sludge not only had the highest solids and nutrient content but also yielded higher treatment efficiency than primary or mixed sludge. In the case of secondary sludge with 4% total solids (TS), the total suspended solids (TSS) concentration was reduced by 32% while soluble chemical oxygen demand concentration increased from 1% to 40% after treatment at 110°C. A high level of nutrient release was also achieved; about 65% total phosphate (TP) solubilized at 110°C. The degree of secondary sludge disintegration was dictated by temperature and hydrogen peroxide dosage. The optimal operating temperature for the system was 110°C, and sludge containing TS up to 8% was treated effectively. Secondary sludge with 8% TS had a TSS reduction of 41% after treatment at 110°C while COD solubilization was about 45%; about 55% TP was solubilized at 10 min holding time. Treatment of sludge with higher solids content would allow for handling larger amounts of sludge at a given period and reduce heating cost per unit of treated sludge. The inter-relationship between the degree of sludge disintegration and changes in chemical and physical properties was also clearly demonstrated here. The treated sludge would be an ideal substrate for anaerobic digestion or phosphorous recovery processes. High levels of nutrients (phosphorus and nitrogen) and metal release, and solids disintegration from sludge containing high solids content would make subsequent resource recovery processes more effective and economical.


Assuntos
Micro-Ondas , Esgotos , Esgotos/química , Oxirredução , Peróxido de Hidrogênio/química , Temperatura , Fosfatos/química , Fósforo
4.
Biomed Pharmacother ; 151: 113187, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35676787

RESUMO

One characteristic of tumor-associated CD4+Foxp3+ regulatory T cells (Tregs) is the high expression of tumor necrosis factor receptor type II (TNFR2), a receptor that mediates the decisive effect of tumor necrosis factor (TNF) in the activation and expansion of Tregs. There is increasing evidence that inhibition of TNFR2 can enhance anti-tumor immune responses. Therefore, we screened Chinese herbal extracts for their capacity to block TNF-TNFR2 interaction. The results showed that the treatment with a Chinese herb extract could inhibit TNFR2-induced biological responses in vitro, including the proliferation of TNFR2+ Tregs. Our subsequent study led to the identification of flavonoid compound scutellarin was responsible for the activity. Our results showed that scutellarin is able to disrupt the interaction of TNF-TNFR2 and inhibited the phosphorylation of p38 MAPK, a down-stream signaling component of TNFR2. Importantly, in vivo scutellarin treatment markedly enhanced the efficacy of tumor immunotherapy with CpG oligodeoxynucleotide in mouse CT26 colon cancer model. This effect of scutellarin was associated with the reduction of the number of tumor-infiltrating TNFR2-expressing Tregs and increased tumor infiltration of interferon-γ-producing CD8+ T cells. Our result also suggests that scutellarin or its analogs may be used as an adjuvant to enhance the anti-tumor effect of immunotherapeutic agent by eliminating TNFR2+ Treg activity.


Assuntos
Apigenina , Glucuronatos , Neoplasias , Receptores Tipo II do Fator de Necrose Tumoral , Animais , Apigenina/farmacologia , Linfócitos T CD8-Positivos , Medicamentos de Ervas Chinesas , Fatores de Transcrição Forkhead/metabolismo , Glucuronatos/farmacologia , Imunidade , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Linfócitos T Reguladores , Fator de Necrose Tumoral alfa/farmacologia
5.
Sci Rep ; 11(1): 10411, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34002002

RESUMO

TRPM4 is a calcium-activated non-selective monovalent cation channel implicated in diseases such as stroke. Lack of potent and selective inhibitors remains a major challenge for studying TRPM4. Using a polypeptide from rat TRPM4, we have generated a polyclonal antibody M4P which could alleviate reperfusion injury in a rat model of stroke. Here, we aim to develop a monoclonal antibody that could block human TRPM4 channel. Two mouse monoclonal antibodies M4M and M4M1 were developed to target an extracellular epitope of human TRPM4. Immunohistochemistry and western blot were used to characterize the binding of these antibodies to human TRPM4. Potency of inhibition was compared using electrophysiological methods. We further evaluated the therapeutic potential on a rat model of middle cerebral artery occlusion. Both M4M and M4M1 could bind to human TRPM4 channel on the surface of live cells. Prolonged incubation with TRPM4 blocking antibody internalized surface TRPM4. Comparing to M4M1, M4M is more effective in blocking human TRPM4 channel. In human brain microvascular endothelial cells, M4M successfully inhibited TRPM4 current and ameliorated hypoxia-induced cell swelling. Using wild type rats, neither antibody demonstrated therapeutic potential on stroke. Human TRPM4 channel can be blocked by a monoclonal antibody M4M targeting a key antigenic sequence. For future clinical translation, the antibody needs to be humanized and a transgenic animal carrying human TRPM4 sequence is required for in vivo characterizing its therapeutic potential.


Assuntos
Anticorpos Monoclonais/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Canais de Cátion TRPM/antagonistas & inibidores , Animais , Anticorpos Monoclonais/uso terapêutico , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células HEK293 , Humanos , Infarto da Artéria Cerebral Média/complicações , Masculino , Técnicas de Patch-Clamp , Ratos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Canais de Cátion TRPM/metabolismo
6.
Phytomedicine ; 61: 152845, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029907

RESUMO

PURPOSE: This study was designed to investigate whether EGCG prevents cardiac I/R mitochondrial impairment and cell apoptosis by regulating miR-30a/p53 axis. METHODS: The H9c2 cardiomyocytes hypoxia/reoxygenation (H/R) model in vitro and myocardial ischemia /reperfusion (I/R) model in vivo were made, with or without EGCG treatment. The levels of I/R-induced creatine kinase-MB (CK-MB) and the release of lactate dehydrogenase (LDH), as well as the adenosine triphosphate (ATP) and cardiac functional impairment were examined. Stablely transfecting miR-30a mimic or inhibitor in H9c2 cardiomyocytes was built. The expression of miR-30a, p53 and related proteins in cells was measured by western blotting and qRT-PCR. Cell viability and apoptosis were examined using CCK-8 assay and flow cytometry. The content of reactive oxygen species (ROS), mitochondrial permeability transition pores (MPTP) opening and mitochondrial transmembrane potential (ΔΨm) in cells was measured by fluorescent probes. The levels of miR-30a and p53, some related proteins expression and apoptosis in the cardiac muscle tissues were determined by quantitative real-time PCR (qRT-PCR), H&E staining, western blotting and TUNEL assays. RESULTS: We found that EGCG preconditioning significantly decreased the levels of CK-MB and LDH, increased the activity of ATP, reduced the apoptotic rate and partially preserved heart function. Furthermore, EGCG decreased ROS levels, MPTP opening and depolarization of ΔΨm, and improved the activity of post-I/R cardiomyocyte. The beneficial effect of EGCG was associated with restored levels of miR-30a expression in the I/R injury that correspond to p53 mRNA downregulation. The regulatory effect of EGCG was greatly enhanced by miR-30a mimic and suppressed by miR-30a inhibitor. More importantly, EGCG pretreatment inhibited the expression of mitochondrial apoptotic related proteins downstream of the miR-30a/p53 pathway. CONCLUSION: This study demonstrated that EGCG pretreatment may attenuate mitochondrial impairment and myocardial apoptosis by regulation of miR-30a/p53 axis.


Assuntos
Catequina/análogos & derivados , MicroRNAs/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/efeitos dos fármacos , Cardiotônicos/farmacologia , Catequina/farmacologia , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo
7.
J Ethnopharmacol ; 224: 381-390, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29920356

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Clitoria ternatea L. (CT), commonly known as Butterfly pea, is used in Indian Ayurvedic medicine to promote brain function and treat mental disorders. Root of CT has been proven to enhance memory, but its role in an animal model of chronic cerebral hypoperfusion (CCH), which has been considered as a major cause of brain disorders, has yet to be explored. AIM OF THE STUDY: To assess the motor and cognitive effects of acute oral administration of CT root methanolic extract and hippocampal long-term plasticity in the CA1 region of the CCH rat model. MATERIALS AND METHODS: Male Sprague Dawley rats (200-300 g) were subjected to permanent bilateral occlusion of common carotid arteries (PBOCCA) or sham operation. Then, these rats were given oral administration of CT root extract at doses of 100, 200 or 300 mg/kg on day 28 post-surgery and tested using behavioural tests (open-field test, passive avoidance task, and Morris water maze) and electrophysiological recordings (under urethane anaesthesia). RESULTS: Treatment with CT root extract at the doses of 200 and 300 mg/kg resulted in a significant enhancement in memory performance in CCH rats induced by PBOCCA. Furthermore, CCH resulted in inhibition of long-term potentiation (LTP) formation in the hippocampus, and CT root extract rescued the LTP impairment. The CT root extract was confirmed to improve the glutamate-induced calcium increase via calcium imaging using primary cultured rat neurons. No significance difference was found in the CaMKII expression. These results demonstrated that CT root extract ameliorates synaptic function, which may contribute to its improving effect on cognitive behaviour. CONCLUSIONS: Our findings demonstrated an improving effect of CT root extract on memory in the CCH rat model suggesting that CT root extract could be a potential therapeutic strategy to prevent the progression of cognitive deterioration in vascular dementia (VaD) and Alzheimer's disease (AD) patients.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Clitoria , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Isquemia Encefálica/fisiopatologia , Cálcio/metabolismo , Células Cultivadas , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Locomoção/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fitoterapia , Raízes de Plantas , Ratos Sprague-Dawley
8.
Int J Mol Sci ; 18(2)2017 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-28208754

RESUMO

Phytoestrogens are estrogen-like compounds of plant origin. The pharmacological activities of phytoestrogens are predominantly due to their antioxidant, anti-inflammatory and lipid-lowering properties, which are mediated via the estrogen receptors (ERs): estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) and possibly G protein-coupled estrogen receptor 1 (GPER). Gypenoside XVII (GP-17) is a phytoestrogen that is widely used to prevent cardiovascular disease, including atherosclerosis, but the mechanism underlying these therapeutic effects is largely unclear. This study aimed to assess the anti-atherogenic effects of GP-17 and its mechanisms in vivo and in vitro. In vivo experiments showed that GP-17 significantly decreased blood lipid levels, increased the expression of antioxidant enzymes and decreased atherosclerotic lesion size in ApoE-/- mice. In vitro experiments showed that GP-17 significantly prevented oxidized low-density lipoprotein (Ox-LDL)-induced endothelial injury. The underlying protective mechanisms of GP-17 were mediated by restoring the normal redox state, up-regulating of the ratio of Bcl-2 to Bax and inhibiting the expression of cleaved caspase-3 in Ox-LDL-induced human umbilical vein endothelial cell (HUVEC) injury. Notably, we found that GP-17 treatment predominantly up-regulated the expression of ERα but not ERß. However, similar to estrogen, the protective effect of GP-17 could be blocked by the ER antagonist ICI182780 and the phosphatidylinositol 3-kinase (PI3K) antagonist LY294002. Taken together, these results suggest that, due to its antioxidant properties, GP-17 could alleviate atherosclerosis via the ERα-mediated PI3K/Akt pathway.


Assuntos
Apoptose/efeitos dos fármacos , Aterosclerose/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Apolipoproteínas E/deficiência , Aterosclerose/genética , Caspase 3/metabolismo , Modelos Animais de Doenças , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Regulação da Expressão Gênica , Gynostemma/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Metabolismo dos Lipídeos , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , Camundongos , Camundongos Knockout , Estrutura Molecular , Fosfatidilinositol 3-Quinase/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
J Sci Food Agric ; 97(10): 3233-3239, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27925223

RESUMO

BACKGROUND: Liquid organic fertilizers (LOFs) are relatively easier to degrade than those of solid organic fertilizers, and the nutrients are readily available for plant uptake. Microwave enhanced advanced oxidation treatment (MW/H2 O2 -AOP) was used to convert solid organic fertilizers (insoluble blood meal, bone meal, feather meal, sunflower ash and a mixture) into LOF. RESULTS: After the MW/H2 O2 -AOP treatment, high soluble nitrogen (11-29%), soluble phosphorus (64%) and potassium (92%), as well as low total suspended solids content could be obtained. The resulting LOF would make the nutrients more bioavailable, and would provide some of them for the plant uptake immediately. Temperature and hydrogen peroxide dosage were found to be significant factors affecting nitrogen release from blood meal and feather meal, while temperature and pH were found to be significant factors for solubilizing phosphorus and potassium from bone meal and ash, respectively. CONCLUSION: The MW/H2 O2 -AOP reduced suspended solids, and released nutrients into solution; therefore, it was an effective treatment method to make LOFs. © 2016 Society of Chemical Industry.


Assuntos
Fertilizantes/análise , Resíduos/análise , Micro-Ondas , Nitrogênio/química , Agricultura Orgânica/instrumentação , Oxirredução/efeitos da radiação , Fósforo/química , Esgotos/química
10.
J Environ Sci Health B ; 51(12): 840-846, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27494645

RESUMO

A newly designed continuous-flow 915 MHz microwave wastewater treatment system was used to demonstrate the effectiveness of the microwave enhanced advanced oxidation process (MW/H2O2-AOP) for treating dairy manure. After the treatment, about 84% of total phosphorus and 45% of total chemical oxygen demand were solubilized with the highest H2O2 dosage (0.4% H2O2 per %TS). The reaction kinetics of soluble chemical oxygen demand revealed activation energy to be in the range of 5-22 kJ mole-1. The energy required by the processes was approximately 0.16 kWh per liter of dairy manure heated. A higher H2O2 dosage used in the system had a better process performance in terms of solids solubilization, reaction kinetics, and energy consumption. Cost-benefit analysis for a farm-scale MW/H2O2-AOP treatment system was also presented. The results obtained from this study would provide the basic knowledge for designing an effective farm-scale dairy manure treatment system.


Assuntos
Esterco , Micro-Ondas , Eliminação de Resíduos Líquidos/métodos , Animais , Análise da Demanda Biológica de Oxigênio , Colúmbia Britânica , Bovinos , Análise Custo-Benefício , Indústria de Laticínios , Feminino , Peróxido de Hidrogênio/química , Cinética , Esterco/análise , Oxirredução , Fósforo , Projetos Piloto , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/instrumentação
11.
Environ Technol ; 36(9-12): 1398-404, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25420588

RESUMO

Phosphorus was recovered from dairy manure via a microwave-enhanced advanced oxidation process (MW/H2O2-AOP) followed by struvite crystallization in a pilot-scale continuous flow operation. Soluble phosphorus in dairy manure increased by over 50% after the MW/H2O2-AOP, and the settleability of suspended solids was greatly improved. More than 50% of clear supernatant was obtained after microwave treatment, and the maximum volume of supernatant was obtained at a hydrogen peroxide dosage of 0.3% and pH 3.5. By adding oxalic acid into the supernatant, about 90% of calcium was removed, while more than 90% of magnesium was retained. As a result, the resulting solution was well suited for struvite crystallization. Nearly 95% of phosphorus in the treated supernatant was removed and recovered as struvite.


Assuntos
Esterco , Fósforo/isolamento & purificação , Cálcio/isolamento & purificação , Indústria de Laticínios , Peróxido de Hidrogênio/química , Compostos de Magnésio/química , Micro-Ondas , Oxirredução , Fosfatos/química , Projetos Piloto , Estruvita
12.
J Environ Sci Health B ; 49(7): 532-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24813989

RESUMO

Dairy manure, acidified using organic acids (acetic, oxalic, and citric acid) were treated with microwave enhanced advanced oxidation process (MW/H2O2-AOP). The effect of a mixture of oxalic acid and commonly used mineral acids (sulfuric and hydrochloric acid) on MW/H2O2-AOP was also examined. Substantial amounts of phosphorus were released under MW/H2O2-AOP, regardless of organic acid or mineral acid used. All three organic acids were good acidifying reagents; however, only oxalic acid could remove free calcium ion in the solution, and improve settleability of dairy manure. The MW/H2O2-AOP and calcium removal process could be combined into a single-stage process, which could release phosphate, solubilize solids and remove calcium from dairy manure at the same time. A mixture of oxalic acid and mineral acid produced the maximum volume of clear supernatant and had an ideal molar ratio of calcium to magnesium for effective struvite (magnesium ammonium phosphate) crystallization process. A single-stage MW/H2O2-AOP would simplify the process and reduce mineral acid consumption compared to a two-stage operation. The results of a pilot scale study demonstrate that MW/H2O2-AOP is effective in treating manure and recovering resource from dairy farms.


Assuntos
Peróxido de Hidrogênio/química , Esterco , Micro-Ondas , Eliminação de Resíduos , Animais , Bovinos , Indústria de Laticínios , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Esterco/análise , Oxirredução , Fósforo/química , Projetos Piloto , Eliminação de Resíduos Líquidos
13.
Artigo em Chinês | MEDLINE | ID: mdl-22356710

RESUMO

OBJECTIVE: To understand the status of occupational health of female migrant workers in different kinds of pharmaceutical industries in Gansu province and to provide the basis for improving occupational health condition. METHODS: One thousand eight hundreds and one female workers from 16 enterprises were selected by cluster sampling in Gansu province and investigated by interviewing and questionnaires. RESULTS: There were statistical significances of education level, status of residency registrations, employment relationship and occupational hazards among female workers in three types of enterprises (P < 0.05 or P < 0.01). The morbidities of skin disease in female workers for three kinds of enterprises were 4.46%, 2.53% and 3.70%, respectively. The morbidities of reproductive system disease in female workers for three kinds of enterprises were 48.57%, 36.70% and 36.11%, respectively. CONCLUSION: The levels of education and working conditions of female workers in the traditional Chinese medicine, western medicine plants are low. There are more severe occupational hazards in female workers of the traditional Chinese medicine plants.


Assuntos
Indústria Farmacêutica , Nível de Saúde , Saúde Ocupacional , Migrantes , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Exposição Ocupacional , Inquéritos e Questionários , Adulto Jovem
14.
J Am Chem Soc ; 131(31): 11222-33, 2009 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-19594162

RESUMO

Synthesis and structural characterization of an octanuclear Cu(I) cluster [Cu(8){Se(2)P(O(i)Pr)(2)}(6)](PF(6))(2) (1) with an empty Cu(8) cubic core involving diisopropyl diselenophosphate (dsep) ligand has been demonstrated despite its high tendency to abstract anions even from the traces of impurities in the solvent. Reaction of 1 with anion sources (Bu(4)NF for F(-); NaBH(4) for H(-), and NaSH for S(2-)) in a 1:1 ratio produced anion-centered Cu(8) clusters with a formula [Cu(8)(X){Se(2)P(O(i)Pr)(2)}(6)](PF(6)) (X = F, 2a; H, 3a; D, 3a') and [Cu(8)(S){Se(2)P(O(i)Pr)(2)}(6)] (4) in high yields. In addition, fluoride- and hydride-centered Cu(8)(I) clusters [Cu(8)(X){Se(2)P(OEt)(2)}(6)](PF(6)) (X = F, 2b; H, 3b) could be generated in approximately 80% yield by direct reaction of [Cu(CH(3)CN)(4)](PF(6)), NH(4)Se(2)P(OEt)(2), and the anion sources (Bu(4)NF for F(-); NaBH(4) for H(-)) in 8:6:1 ratio. Whereas the structural elucidation of complexes 2 and 4 revealed an anion-centered cubic Cu(8) core surrounded by six dsep ligands, it was a tetracapped tetrahedral copper framework with a hydride in the center in compounds 3. All Cu...Cu distances along either the edge of the cube in 2 and 4 or the tetracapped tetrahedron in 3 are shorter than those identified in 1. Although the cubic (or spherical) contraction of the copper framework that was identified in a series of closed-shell anion-centered (except a hydride) Cu(8) cube having T(h) symmetry could be explained by the existence of strong anion-cation attractions, it was definitely a surprise that the hydride, which is the smallest closed-shell anion and spherical too, induced a tetrahedral contraction of four out of the eight Cu atoms in the empty cube 1, resulting in a tetracapped-tetrahedral geometry and reducing the symmetry to T from T(h). Furthermore the fact that the encapsulated anion induced modulation of the copper core size and symmetry was fully reproduced by DFT calculations on model compounds. To the best of our knowledge, this demonstrated the first example of the reduction of molecular symmetry (from T(h) to T) simply by changing the encapsulated species without altering the general bonding pattern of the surrounding ligands. We also demonstrated that the hydride can easily replace other anions (Cl(-), Br(-), F(-), S(2-), Se(2-)) in a very facile manner to produce hydride-centered species. Eventually, compounds 3 were stable in the presence of other anions, and hydride/deuteride exchange could not be achieved.


Assuntos
Cobre/química , Selênio/química , Ânions , Hidrogênio
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 72(5): 1066-70, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19201257

RESUMO

Aqueous thiol-capped CdSe QDs with a narrow, symmetric emission were prepared under a low temperature. Based on the fluorescence enhancement of thiol-stabilized CdSe quantum dots (QDs) caused by edaravone, a simple, rapid and specific quantitative method was proposed to the edaravone determination. The concentration dependence of fluorescence intensity followed the binding of edaravone to surface of the thiol-capped CdSe QDs was effectively described by a modified Langmuir-type binding isotherm. Factors affecting the fluorescence detection for edaravone with thiol-stabilized CdSe QDs were studied, such as the effect of pH, reaction time, the concentration of CdSe QDs and so on. Under the optimal conditions, the calibration plot of C/(I-I(0)) with concentration of edaravone was linear in the range of (1.45-17.42) microg/mL (0.008-0.1 micromol/L) with correlation coefficient of 0.998. The limit of detection (LOD) (3sigma/kappa) was 0.15 microg/mL (0.0009 micromol/mL). Possible interaction mechanism was discussed.


Assuntos
Bioensaio/métodos , Cádmio/química , Sequestradores de Radicais Livres/análise , Pontos Quânticos , Selênio/química , Antipirina/análogos & derivados , Antipirina/análise , Edaravone , Fluorescência , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Água/química
16.
J Environ Sci Health B ; 43(4): 350-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18437623

RESUMO

Microwave digestion of liquid dairy manure was tested for the release of nutrients, such as orthophosphates, ammonia-nitrogen, magnesium, calcium and potassium, both with and without the aid of an oxidizing agent (hydrogen peroxide). The orthophosphate to total phosphorus ratio of the manure increased from 21% to greater than 80% with 5 minutes of microwave treatment. More than 36% of total chemical oxygen demand (t-COD) of the manure was reduced when microwave digestion was assisted with peroxide addition. In addition, the volatile fatty acids (VFAs) distribution shifted to simpler chain acids (acetic acid in particular) with an increase in operating temperature. In the second part of the study, digested manure with increased soluble phosphate was tested for the recovery of struvite (magnesium ammonium phosphate) at different pH. It was found that up to 90% of orthophosphate can be removed from the solution. Overall, it was concluded that the oxidizing agent-assisted microwave digestion process can be used upstream of anaerobic digestion, following which the anaerobically digested manure can be used for struvite recovery. Thus, this microwave digestion process presents the potential for enhanced efficiencies in both manure digestion and struvite recovery.


Assuntos
Compostos de Magnésio/análise , Esterco/análise , Micro-Ondas , Fosfatos/análise , Fósforo/química , Fósforo/efeitos da radiação , Gerenciamento de Resíduos/métodos , Animais , Bovinos , Indústria de Laticínios/métodos , Digestão , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Feminino , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Compostos de Magnésio/química , Compostos de Magnésio/efeitos da radiação , Oxirredução , Fosfatos/química , Fosfatos/efeitos da radiação , Solo/análise , Microbiologia do Solo , Solubilidade , Estruvita , Fatores de Tempo
17.
Bioresour Technol ; 99(5): 1169-76, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17467983

RESUMO

A pilot-scale sequencing batch reactor (SBR) was operated at a dairy farm to test real-time based control in winter operation conditions. A combination of high loading and low oxidation reduction potential (ORP) conditions in the aerobic stage of SBR treatment (an end value of -50 to -150 mV) inhibited nitrification while maintaining carbon removal. After a period of over-aeration over several cycles, the ORP at the end of the aerobic stage increased to values of 50-75 mV. Subsequently, nitrification was observed, accompanied by higher total cycle times. Significant increase in removal efficiencies of ammonical nitrogen (alpha<0.0001) and chemical oxygen demand (alpha<0.001) were observed for the high ORP phase. It is postulated that higher ORP regimes are needed for nitrification. In low ORP regimes, nitrification is absent or occurs at an extremely low rate. It is also noted that nitrifying systems treating high strength animal manure can possibly lead to unacceptably high levels of effluent nitrate+nitrite nitrogen (NO(x)-N). Two manure management schemes are proposed that give the farmer an option to either retain the nutrients, or remove them from the wastewater. Some advantages and disadvantages of the schemes are also discussed.


Assuntos
Esterco/análise , Eliminação de Resíduos Líquidos/métodos , Animais , Reatores Biológicos , Bovinos , Indústria de Laticínios , Feminino , Fertilizantes , Oxirredução , Estações do Ano , Fatores de Tempo
18.
Biochim Biophys Acta ; 1783(1): 118-30, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18070605

RESUMO

Cav1.2 L-type calcium channels are essential in heart and smooth muscle contraction. Rat Cav1.2 gene contains 11 alternatively spliced exons (1a, 1, 8a, 8, 9*, 21, 22, 31, 32, 32-6nt and 33) which can be assorted to generate a large number of functionally distinct splice variants. Until now, it is unknown whether the utilization of these alternatively spliced exons is altered in the hypertrophied hearts of hypertensive rats. By comparing the assortments of these 11 exons in full-length Cav1.2 transcripts derived from Spontaneously Hypertensive Rats (SHRs) and Wistar Kyoto Rats (WKYs) hearts, we found that the inclusion of Cav1.2 alternative exons was significantly different between the two rats both at individual loci and in combinatorial arrangements. Functional characterizations of three Cav1.2 channel splice variants that were identified to be significantly altered in SHR hypertrophied cardiomyocytes demonstrated distinct whole-cell electrophysiological properties when expressed in HEK 293 cells. Interestingly, aberrant splice variants which included or excluded both mutually exclusive exons 21/22 or exons 31/32 were found to be increased in hypertensive rats. Two aberrant splice variants that included both exons 21 and 22 were found to be unable to conduct currents even though they expressed proteins with the predicted molecular mass. Characterization of one of the aberrant splice variants showed that it exerted a dominant negative effect on the functional Cav1.2 channels when co-expressed in HEK293 cells. The altered combinatorial splicing profiles of Cav1.2 transcripts identified in SHR hearts provide a different and new perspective in understanding the possible role of molecular remodeling of Cav1.2 channels in cardiac hypertrophy as a consequence of hypertension.


Assuntos
Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Miocárdio/metabolismo , Splicing de RNA/genética , Animais , Pressão Sanguínea , Linhagem Celular , DNA Complementar/genética , Eletrofisiologia , Éxons/genética , Regulação da Expressão Gênica , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Tamanho do Órgão , Técnicas de Patch-Clamp , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transcrição Gênica/genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-17129949

RESUMO

The effects of an advanced oxidation process combining microwave, hydrogen peroxide and acid hydrolysis in a single stage (MW/H2O2/H+ -AOP) on the process efficiency of sewage sludge treatment and nutrient recovery were investigated. At lower temperature regimes (60-80 degrees C), the soluble phosphate was substantially higher in a two-stage process than in a single stage MW/H2O2/H+ -AOP process. However, higher soluble phosphate concentration was obtained for single-stage treatment at the higher operating temperature regimes (100-120 degrees C). With the addition of an inorganic acid, a very high yield of soluble phosphate was obtained in the solution at 120 degrees C. In tests with acid addition, soluble ammonia increased as temperature increased. For single stage MW/H2O2/H+ -AOP, maximum soluble ammonia was obtained at 120 degrees C. Significant concentrations of soluble COD were also obtained in this treatment. A threshold temperature of 80 degrees C was observed, at which all of the COD could be solubilized. However, at higher temperatures (100-120 degrees C), further oxidation processes occurred to form carbon dioxide, resulting in decreased amounts of soluble COD in the solution.


Assuntos
Peróxido de Hidrogênio/química , Micro-Ondas , Fosfatos/análise , Esgotos/química , Purificação da Água/métodos , Amônia/análise , Amônia/química , Amônia/efeitos da radiação , Fosfatos/química , Fosfatos/efeitos da radiação , Solubilidade , Purificação da Água/instrumentação
20.
Artigo em Inglês | MEDLINE | ID: mdl-17000550

RESUMO

This study focused on the efficacy of the microwave/hydrogen peroxide advanced oxidation process (MW/H2O2-AOP) on the secondary sludge treatment. The results indicated that at temperatures of 80 degrees C and above, essentially all of the chemical oxygen demand (COD) was solubilized by the combined MW/H2O2-AOP. This process also solubilized nutrients (nitrogen, phosphorus and metals) from sludge which can be extracted for other purposes, such as struvite crystallization. Based on a stoichiometric molar ratio of 1:1:1 for Mg:NH3:PO4, ammonia was found to be the limiting nutrient without any H2O2 addition in the process at all temperatures. With the addition of H2O2, ortho-phosphate became the limiting nutrient. In all treatments, magnesium was non-limiting, thus magnesium addition is not required for subsequent struvite crystallization. The MW/H2O2-AOP also enhanced the pasteurization or sterilization of sludge. The MW/H2O2-AOP provides novel sludge management options for the wastewater industry, not only in solubilization of carbon for further methane production, but also in nutrients extraction for crystallization for use as fertilizer.


Assuntos
Peróxido de Hidrogênio/química , Micro-Ondas , Esgotos , Aerobiose , Metais/química , Nitrogênio/química , Oxirredução , Fósforo/química , Solubilidade , Esterilização , Temperatura
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