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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(6): 684-692, 2020 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879126

RESUMO

OBJECTIVES: To evaluate the repairing ability of nano-pearl powder bone substitute in rabbit with defect of distal femur bone. METHODS: Thirty-two New Zealand rabbits were randomly divided into four groups: a nano-pearl powder/recombinant human bone morphogenetic protein 2 (rhBMP-2)/hyaluronic acid group, a nano-pearl powder/hyaluronic acid group, a nano-pearl powder group and a blank control group (n=8 in each group). A defect with the diameter of 7 mm and height of 10 mm was prepared at the distal femoral metaphysis line of the rabbit.Different bone substitutes were planted, and the effect of repair was evaluated by macroscopic observation, imaging examination, and histopathological examination. RESULTS: The results of imageology showed that: the bone repairing effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the 3 experimental groups was better than that in the blank control group; The results of histology showed that: at the 4th, 8th and 12th weeks after the modeling operation, the speed of bone repair in the nano-pearl powder/rhBMP-2/hyaluronic acid group was faster than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group, and which in the blank control group was far slower than that in the 3 experimental groups. The results of immunohistochemistry staining for osteocalcin antibody showed that: the osteogenic effect in the nano-pearl powder/rhBMP-2/hyaluronic acid group was better than that in the pure pearl powder group and the nano-pearl powder/hyaluronic acid group (both P<0.05); there was no significant difference between the nano-pearl powder/hyaluronic acid group and the pure pearl powder group (P>0.05); however, there was significant difference between the pure pearl powder group and the blank control group (P<0.05). According to the staining results of Type I collagen antibody, there was no significant difference in the osteogenic effect between the nano-pearl powder/rhBMP-2/hyaluronic acid group and the nano-pearl powder/hyaluronic acid group (P>0.05), but the osteogenic effect in the nano-pearl powder/hyaluronic acid group was better than that in the pure pearl powder group and the blank control group (both P<0.05). CONCLUSIONS: Nano-pearl powder and its bone substitute can promote the repair of bone defect, and the nano-pearl powder which contains rhBMP-2 has better osteogenic and repairing effect on defect.


Assuntos
Substitutos Ósseos , Animais , Proteína Morfogenética Óssea 2 , Colágeno , Fêmur , Humanos , Osteogênese , Pós , Coelhos , Proteínas Recombinantes , Fator de Crescimento Transformador beta
2.
Medicine (Baltimore) ; 99(31): e20750, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32756078

RESUMO

BACKGROUND: Type 2 diabetes is a kind of metabolic disease. Its clinical characteristic is hyperglycemia. Recently, more and more elderly people suffer from type 2 diabetes, and the glycemic variability of the elderly is greater. In addition, blood sugar variation is more likely to cause diabetes complications than simple hyperglycemia. Sancai podwer (SC) is based on the theory of traditional Chinese medicine and gradually formed in the summary of clinical experience. It has the effect of lowering blood sugar and alleviating clinical symptoms of diabetes. But the existing evidence of its efficacy on glycemic variability is insufficient. So, in our study, the randomized controlled trials will be used as a research method to explore the effects of SC on glycemic variability of type 2 diabetes. METHOD: We will use randomized controlled experiments based on the recommended diagnostic criteria, inclusion and exclusion criteria. A total of 60 elderly patients with type 2 diabetes will be randomly divided into treatment group and control group, 30 cases in each group. The control group will receive conventional western medicine and the intervention group will receive SC combined with western medicine. The standard deviation and coefficient of variation of blood glucose level will be used as evaluation indexes. DISCUSSION: This study can provide evidence for the clinical efficacy and safety of SC in elderly patients with type 2 diabetes mellitus. TRIAL REGISTRATION: This study is registered on the Chinese Clinical Trial Registry: ChiCTR2000032611.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Glicemia/efeitos dos fármacos , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/administração & dosagem , Metformina/uso terapêutico , Pós , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Bioresour Technol ; 316: 123944, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32769000

RESUMO

Xylonic acid can be produced with high-yield from hemicelullosic xylose, which accounts for 25% of the total sugars in lignocellulosic material. The key barrier associated with efficient bio-oxidation of hemicellulosic xylose to xylonic acid is the serious foam formed in downstream air-aerated and agitated bioreaction process, which caused by the high viscosity of concentrated pre-hydrolysate. Powdered activated carbon treatment can selectively absorb the non-sugar compounds with relatively low losses of xylose, which is beneficial for the valuable xylose derivatives production. In this present study, powdered activated carbon was employed for treating the concentrated pre-hydrolysate from diluted acid pretreated corncob. The results indicated that the powdered activated carbon treatment significantly reduced the viscosity of concentrated pre-hydrolysate and the other non-sugar compounds, which enabled scale-up lignocellulosic xylonic acid production using the air-aerated and agitated bioreactor.


Assuntos
Gluconobacter oxydans , Carvão Vegetal , Fermentação , Polissacarídeos , Pós , Xilose
4.
Sci Total Environ ; 743: 140791, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758844

RESUMO

This paper assesses the applicability of a new carob waste-derived powdered activated carbon (PAC) obtained by steam activation for pharmaceutical compounds (PhCs) removal in urban wastewater treatment plants (WWTPs) with activated sludge (AS) secondary treatment. The new carob-derived PAC presents chemical and textural properties similar to a high-performing commercial PAC produced from vegetable source by physical activation. The adsorption isotherms of three target PhCs, carbamazepine, diclofenac and sulfamethoxazole, spiked (at around 100 µg/L) in mixed liquor (ML) and in clarified-ML from the AS-bioreactor of a WWTP show: (i) minor reduction of PAC capacity with real MLs compared to clarified MLs; (ii) the higher the PhC hydrophobicity, the higher the PAC adsorption capacity in both water matrices; (iii) hydrophobic interactions probably overweight electrostatic interactions between the PhCs and the slightly positively charged PAC in these real water matrices with background organics and inorganics. The PhC adsorption results with ML and clarified-ML are used to calibrate the IAST-based tracer model (TRM) and predict the new PAC performance when added to AS-bioreactor vs. in post-secondary treatment, at the PhC naturally-occurring trace concentrations. The modelling projections show (i) one needs higher PAC doses than those reported in the literature, particularly in post-treatment, and (ii) the benefits of PAC dosing to the bioreactor, with only a slightly higher PAC dose being needed when compared to its post-secondary dosing and minimising the capital investment.


Assuntos
Poluentes Químicos da Água/análise , Purificação da Água , Adsorção , Carvão Vegetal , Galactanos , Mananas , Gomas Vegetais , Pós , Eliminação de Resíduos Líquidos , Águas Residuárias
5.
Int J Nanomedicine ; 15: 5361-5376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801694

RESUMO

Background and Aim: Polymeric nanoparticles (NPs) have received much attention as promising carrier systems in lung cancer and brain metastases. Methods: Here, for the first time, we investigated the feasibility of using inhaled cholesterol-PEG co-modified poly (n-butyl) cyanoacrylate NPs (CLS-PEG NPs) of docetaxel (DTX) for sustained pulmonary drug delivery in cancer metastasis. Results: Spray-dried or freeze-dried NPs yielded sustained drug release in vitro. In vitro inhalation evaluation data indicated that the inhalation formulation had better inhalability. Compared with intravenous (IV) administration, pharmacokinetic data suggested that the inhalation formulation prolonged plasma concentration of DTX for greater than 24 h and is more quickly and completely absorbed into the rat lung after intratracheal (IT) administration. Furthermore, freeze-dried powders were found to increase the t1/2 and area under curve (AUC) by 2.3 and 6.5 fold compared to the free drug after IT administration, and spray-dried powders were found to increase the t1/2 and AUC by 3.4 and 8.8 fold, respectively. After pulmonary administration of the inhalation formulation, DTX appeared to prolong the pulmonary absorption time. In addition, the inhalation formulation was distributed to the brain in a sustained release manner. Conclusion: These experimental results demonstrated that freeze- and spray-dried powders have the potential for pulmonary sustained release, and they also have the potential to be used as a novel treatment for the delivery of drugs that pass through the air-blood barrier and enter the brain and are efficient carriers for the treatment of brain metastasis.


Assuntos
Antineoplásicos/administração & dosagem , Docetaxel/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/administração & dosagem , Células A549 , Administração por Inalação , Animais , Encéfalo/efeitos dos fármacos , Colesterol/química , Preparações de Ação Retardada , Docetaxel/farmacocinética , Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Embucrilato/química , Feminino , Liofilização , Humanos , Pulmão/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Nanopartículas/química , Tamanho da Partícula , Polímeros/química , Pós/química , Ratos Wistar , Distribuição Tecidual
6.
Sci Total Environ ; 745: 141090, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32758744

RESUMO

In this study, the effect of a high concentration of powdered activated carbon (PAC) on pollutant removal and microbial communities was systematically investigated. Micropollutant removal by the 'control' MBR (without PAC addition) was pollutant-specific and was mainly controlled by their molecular properties. The PAC-MBR achieved enhanced removal of micropollutant by 10% (ofloxacin) to 40% (caffeine). Analysis of the microbial communities in the sludge samples collected from both MBRs indicated an increase in the abundance of 24 (out of 31) genera following PAC addition. Notably, bacterial diversity enriched, particularly in the anoxic zone of the PAC-MBR, indicating a positive impact of recirculating mixed liquor containing PAC from the aerobic to the anoxic zone. In addition, PAC improved the abundance of Comamonas and Methanomethylovorans (up to 2.5%) that can degrade recalcitrant micropollutants. According to the quantitative PCR (qPCR) analysis, the copies of functional genes (nirS, nosZ and narG) increased in PAC-MBR. This study demonstrated that MBR could be operated at a high PAC concentration without compromising the pollutant removal and microbial community evolution during wastewater treatment.


Assuntos
Carvão Vegetal , Microbiota , Reatores Biológicos , Membranas Artificiais , Pós , Esgotos , Eliminação de Resíduos Líquidos
7.
Sci Total Environ ; 746: 141104, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32763603

RESUMO

In order to eliminate micropollutants from wastewater, the use of powdered activated carbon (PAC) is a suitable and common technique. Many studies already proved the successful elimination of micropollutants from wastewater using PAC. However, it still remains a challenge to completely retain the applied PAC within the wastewater treatment plant (WWTP) without considerable emission of PAC into receiving waters. The present study investigates possible toxic effects of micropollutant-loaded PAC from a WWTP in acute and chronic tests with the aquatic organism Daphnia magna. Furthermore, the well-studied micropollutant diclofenac as well as unloaded, native PAC and experimentally diclofenac-loaded PAC were tested. The acute tests resulted in median effect concentrations (EC50) after 48 h of 53 mg/L for diclofenac, 217 mg/L for native PAC and 414 mg/L for diclofenac-loaded PAC. No effects were detected for the loaded PAC from the WWTP although D. magna ingested the PAC. The chronic tests revealed that diclofenac had effects on growth, reproduction and mortality (median lethal concentration 17.0 mg/L). Exposure to native and diclofenac-loaded PAC showed clear effects on growth and a reproduction inhibition of 80% in the highest tested concentrations. The calculated reproduction EC10 values were 0.8 mg/L for native PAC and 0.3 mg/L for diclofenac-loaded PAC. For the loaded PAC from the WWTP, no effects were observed on reproduction, growth and mortality during the 21-day exposure albeit the fact that the animals ingested the PAC into their gastrointestinal system. Based on these findings PAC from WWTP can be considered as not harmful to D. magna even if complete retention of the PAC at the WWTP cannot be guaranteed.


Assuntos
Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carvão Vegetal/toxicidade , Daphnia , Pós , Eliminação de Resíduos Líquidos
8.
Ecotoxicol Environ Saf ; 202: 110882, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32619891

RESUMO

Extracellular polymeric substances (EPS) which wrapped on sludge particles were deemed to hinder the outflowing of combined water in sludge system. The complex composition of EPS was the bottleneck for revealing its relationship with sludge dewaterability. In this study, a combined modified corn-core powder (MCCP) and sludge-based biochar (SBB) condition was executed to treat sludge for enhancing dehydration performance, and the concentration and the form distribution of organics in EPS, the variances of protein secondary structures were investigated. Correlation between the sludge dewaterability and EPS components were performed, found strong correlations among the net sludge solids yield (YN) and the specific resistance of filtration (SRF) (R = -0.923), Zeta potential (R = -0.971). Furthermore, the relationship between the secondary structures of protein and dehydration performance were strong related. With the optimal dosage of SBB and MCCP, aggregated strands and α -helix were released, indicated that the unfolding and despiralization in soluble EPS (S-EPS) were improved, disordered the sludge network, reduced the flowing resistance of bound water, finally enhancing sludge dewaterability.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Eliminação de Resíduos Líquidos , Carvão Vegetal , Filtração , Pós , Esgotos/química , Água/química , Zea mays
9.
Lancet Glob Health ; 8(8): e1071-e1080, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32710863

RESUMO

BACKGROUND: Universal home fortification of complementary foods with iron-containing multiple micronutrient powders (MNPs) is a key intervention to prevent anaemia in young children in low-income and middle-income countries. However, evidence that MNPs might promote infection raises uncertainty about whether MNPs give net health benefits and are cost-effective. We aimed to determined country-specific net benefit or harm and cost-effectiveness of universal provision of MNPs to children aged 6 months. METHODS: We developed a microsimulation model to estimate net country-specific disability-adjusted life-years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs) due to anaemia, malaria, and diarrhoea averted (or increased) by provision of a 6-month course of MNPs to children aged 6 months, compared with no intervention, who would be followed up for an additional 6 months (ie, to age 18 months). Anaemia prevalence was derived from Demographic and Health Surveys or similar national surveys, and malaria and diarrhoea incidence were sourced from the Global Burden of Disease Study. Programme and health-care costs were modelled to determine cost per DALY averted (US$). Additionally, we explored the effects of reduced MNP coverage in a sensitivity analysis. FINDINGS: 78 countries (46 countries in Africa, 20 in Asia or the Middle East, and 12 in Latin America) were included in the analysis, and we simulated 5 million children per country. 6 months of universal distribution of daily MNPs, assuming 100% coverage, produced a net benefit (DALYs averted) in 54 countries (24 in Africa, 19 in Asia and the Middle East, 11 in Latin America) and net harm in 24 countries (22 in Africa, one in Asia, and one in Latin America). MNP intervention provided a benefit on YLDs associated with anaemia, but these gains were attenuated and sometimes reversed by increases in YLLs associated with malaria and diarrhoea, reducing the benefits seen for DALYs. In the 54 countries where MNP provision was beneficial, the median benefit was 28·1 DALYs averted per 10 000 children receiving MNPs (IQR 20·6-40·4), and median cost per DALY averted was $3576 (IQR 2474-4918). DALY effects positively correlated with moderate and severe anaemia prevalence in Asia, the Middle East, and Latin America, but correlated inversely in Africa. Suboptimal coverage markedly reduced DALYs averted and cost-effectiveness. INTERPRETATION: Net health benefits of MNPs vary between countries, are highest where prevalence of moderate and severe anaemia is greatest but infection prevalence is smallest, and are ameliorated when coverage of the intervention is poor. Our data provide country-specific guidance to national policy makers. FUNDING: International Union of Nutrition Sciences.


Assuntos
Anemia/prevenção & controle , Países em Desenvolvimento , Suplementos Nutricionais , Ferro na Dieta/economia , Ferro na Dieta/uso terapêutico , Micronutrientes/economia , Micronutrientes/uso terapêutico , Análise Custo-Benefício , Suplementos Nutricionais/economia , Humanos , Lactente , Pós , Resultado do Tratamento
11.
Water Res ; 183: 116093, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32645580

RESUMO

Many PACl (poly-aluminum chloride) coagulants with different characteristics have been trial-produced in laboratories and commercially produced, but the selection of a proper PACl still requires empirical information and field testing. Even PACls with the same property sometimes show different coagulation performances. In this study, we compared PACls produced by AlCl3-titration and Al(OH)3-dissolution on their performance during coagulation-flocculation, sedimentation, and sand filtration (CSF) processes. The removal targets were particles of superfine powdered activated carbon (SPAC), which are used for efficient adsorptive removal of micropollutants, but strict removal of SPAC is required because of the high risk of their leakage after CSF. PACls of high-basicity produced by AlCl3-titration and Al(OH)3-dissolution were the same in terms of the ferron assay and colloid charge, but their performance in CSF were completely different. High-basicity Al(OH)3-dissolution PACls formed large floc particles and yielded very few remaining SPAC particles in the filtrate, whereas high-basicity AlCl3-titration PACls did not form large floc particles. High-basicity PACls produced by Al(OH)3-dissolution were superior to low-basicity PACl in lowering remaining SPAC particles by the same method because of their high charge neutralization capacity, although their floc formation ability was similar or slightly inferior. However, high-basicity Al(OH)3-dissolution PACl was inferior when the sulfate ion concentration in the raw water was low. Sulfate ions were required in the raw water for high-basicity PACls to be effective in floc formation. In particular, very high sulfate concentrations were required for high-basicity AlCl3-titration PACls. The rate of hydrolysis, which is related to the polymerization of aluminum species, is a key property, besides charge neutralization capacity, for proper coagulation, including formation of large floc particles. The aluminum species in the high-basicity PACls, in particular that produced by AlCl3-titration, was resistant to hydrolysis, but sulfate ions in raw water accelerated the rate of hydrolysis and thereby facilitated floc formation. Normal-basicity Al(OH)3-dissolution PACl was hydrolysis-prone, even without sulfate ions. Aluminum species in the high-basicity AlCl3-titration PACl were mostly those with a molecular weight (MW) of 1-10 kDa, whereas those of high-basicity Al(OH)3-dissolution PACls were mostly characterized by a MW > 10 kDa. Normal-basicity Al(OH)3-dissolution PACl was the least polymerized and contained monomeric species.


Assuntos
Carvão Vegetal , Purificação da Água , Hidróxido de Alumínio , Floculação , Pós , Areia , Solubilidade , Sulfatos , Água
12.
AAPS PharmSciTech ; 21(5): 181, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32607628

RESUMO

Cocrystals have gained a lot of consideration regarding its superior role in enhancement of solubility and dissolution of the included API. Cocrystals could be converted to coamorphous systems via different techniques like milling and quench cooling; however, the use of spray-drying technique has not been investigated before. So, the aim of this study was to explore the effect of spray drying on the amorphization of indomethacin/nicotinamide, INDNIC, as model cocrystals. Spray-drying operating parameters were optimized using the Taguchi design of experiment for maximum powder yield and low moisture content. The obtained INDNIC spray-dried cocrystals were characterized for their degree of crystallinity, morphology, moisture content, and dissolution performance. In addition, stability study was performed at different temperature and humidity conditions. Experimental design results delineate that spray-drying inlet temperature and cocrystal concentrations as the most influential factors for maximum powder yield and low moisture content. Powder X-ray diffraction and differential scanning calorimetry studies revealed the conversion of INDNIC cocrystals to a partial coamorphous or coamorphous structure without dissociation of INDNIC molecular structure. INDNIC coamorphous powders showed a significantly higher release of IND compared with cocrystals and remain physically stable for 2 months when stored in the refrigerator.


Assuntos
Dessecação/métodos , Estabilidade de Medicamentos , Indometacina/química , Niacinamida/química , Varredura Diferencial de Calorimetria , Composição de Medicamentos/métodos , Estrutura Molecular , Pós/química , Solubilidade , Difração de Raios X
13.
Food Chem ; 332: 127420, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32622191

RESUMO

The outbreaks of Cronobacter sakazakii, Salmonella spp, and Bacillus cereus in powdered foods have been increasing in worldwide. However, an effective method to pasteurize powdered foods before consumption remains lacking. A prototype Intense Pulsed Light (IPL) system was developed to disinfect powdered foods under different IPL and environmental conditions. Synergistic effect of IPL and TiO2 photocatalysis on microbial inactivation was studied. The results show that high energy intensity of each pulse, high peak intensity, and short pulsed duration contributed to a high microbe inactivation. With TiO2 photocatalysis, one additional log10 reduction was achieved, bringing the total log reduction to 4.71 ± 0.07 (C. sakazakii), 3.49 ± 0.01 (E. faecium), and 2.52 ± 0.10 (B. cereus) in non-fat dry milk, and 5.42 ± 0.10 (C. sakazakii), 4.95 ± 0.24 (E. faecium), 2.80 ± 0.23 (B. cereus) in wheat flour. IPL treatment combined with the TiO2 photocatalysis exhibits a strong potential to reduce the energy consumption in improving the safety of powdered foods.


Assuntos
Cronobacter sakazakii/efeitos da radiação , Cronobacter/efeitos da radiação , Farinha/microbiologia , Conservação de Alimentos/métodos , Viabilidade Microbiana/efeitos da radiação , Leite/microbiologia , Triticum/microbiologia , Animais , Bacillus cereus/crescimento & desenvolvimento , Bacillus cereus/efeitos da radiação , Cronobacter/crescimento & desenvolvimento , Microbiologia de Alimentos , Conservação de Alimentos/instrumentação , Luz , Pós/química , Salmonella/crescimento & desenvolvimento , Salmonella/efeitos da radiação
14.
Food Chem ; 332: 127444, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32653769

RESUMO

By-products of Belgian endive represent an interesting yet underutilised source of dietary fibre (DF). Dietary fibre concentrates (DFC) that are low in sugar and neutral in taste are sought by the food industry to increase DF content and improve texture in food products. The aim was to set up a biorefinery process to produce DFC from forced roots of Belgian endive (DFC-BE) and characterise the resulting product. As a control, non-treated forced roots powder (FRP-BE) was tested. Water extraction significantly (p < 0.05) decreased the content of sugars, phenolic acids (PA) and sesquiterpene lactones (SL) in DFC-BE. In contrast, total dietary fibre concentration (TDF) was higher in DFC-BE (81.82 g/100 g DW) in comparison to FRP-BE (49.04 g/100 g DW). DFC-BE offers an excellent water holding capacity (WHC) of 14.71 g water/g DW and a swelling capacity (SWC) of 23.46 mL water/g DW, suggesting possible use as a functional food ingredient.


Assuntos
Chicória/química , Fibras na Dieta/análise , Extratos Vegetais/química , Resíduos/análise , Bélgica , Alimento Funcional/análise , Raízes de Plantas/química , Pós/química , Verduras/química
15.
Chemosphere ; 260: 127478, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32683022

RESUMO

Slow-releasing carbon source tablets were manufactured for an in-situ biological denitrification system. The average zero-order nitrate degradation rates seen, from highest to lowest, were in microcosms to which lactate, fumarate, propionate, and formate had been added. Fumarate was approximately 80% cheaper than lactate, and consequently was determined to be the most optimal slow-releasing carbon source in tablet form. The slow-releasing precipitating tablet (SRPT) and slow-releasing floating tablet (SRFT) were manufactured with hydroxypropyl methylcellulose (HPMC) as the agent of release control, microcrystalline cellulose pH 101 (MCC 101) as the binder, #8 sand as the precipitation agent, and calcium carbonate and citric acid as floating agents. Fourier transform infrared spectroscopy and powder X-ray diffraction indicated that the crystal arrangement in the SRPTs and SRFTs was maintained and ordered in a manner similar to raw excipients. SRFTs floated in water within 30 min and remained so for 5 d due to the buoyancy of carbon dioxide. The carbon source release rate was proportional to the quantity of HPMC added. The longevities of SRPT with 300 mg of HPMC and SRFT with 400 mg of HPMC were 25.4 d and 37.3 d, respectively. This study observed that SRPT and SRFT were manufactured effectively and are suitable for in-situ slow-releasing biological systems.


Assuntos
Desnitrificação , Água Subterrânea/química , Preparações de Ação Retardada , Excipientes/química , Derivados da Hipromelose , Nitratos , Pós , Solubilidade , Comprimidos , Água/química
16.
Food Chem ; 333: 127490, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32653682

RESUMO

The aims of this study were to evaluate the role of encapsulant materials on the stability of bioactive compounds of red ginger extract powder during storage and determine the composition of the encapsulant materials which produced red ginger extract powder with best stability of bioactive compounds during storage. This study consisted of three compositions of encapsulant materials which are maltodextrin:gum arabic with ratio 10:0, 8:2, and 5:5. The results showed that several compositions of encapsulant materials produced different stability of bioactive compounds of red ginger extract powder. Based on the study result, increasing amount of gum arabic used had better protection to the stability of bioactive compounds of the powders during storage.


Assuntos
Armazenamento de Medicamentos , Gengibre/química , Extratos Vegetais/química , Cápsulas , Goma Arábica/química , Polissacarídeos/química , Pós
17.
Food Chem ; 333: 127488, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32682229

RESUMO

A mild mixed-solvent of n-hexane/isopropanol is proposed for extracting total mineral oil hydrocarbons (MOH) from commercial milk powder products. Unlike acid-hydrolysis, the mixed-solvent extraction was performed at ambient temperature and the low-boiling-point hydrocarbons were retained to the greatest extent. After extraction, total MOH was determined by on-line liquid chromatography-gas chromatography with a flame ionization detector (LC-GC-FID). The validation of the proposed extraction method revealed a recovery efficacy of 83.0-107.5% and a limit of quantification of 0.5 mg/kg. Then, the total MOH in ten commercial milk powders was determined and mineral oil saturated hydrocarbons (MOSH)/polyolefin oligomeric saturated hydrocarbons (POSH) were found to be within the range of 0.61-5.46 mg/kg. The comparison of the total and surface MOSH/POSH indicated that a major part of the contamination was derived from sources before packaging. The present study provides a robust method for the extraction and determination of total MOH in milk powders.


Assuntos
Fracionamento Químico/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos/análise , Hidrocarbonetos/isolamento & purificação , Leite/química , Óleo Mineral/química , Solventes/química , Animais , Hidrocarbonetos/química , Pós
18.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1726-1733, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489055

RESUMO

Bufonis Venenum(toad venom) is prepared from the dried secretion of Bufo bufo gargarizans or B. melanostictus. Toad venom powder is one of the processed slices of crude material toad venom. In the present study, the global quality control method and standard of toad venom and its processed slice, toad venom powder were established, including TLC identification, characteristic chromatogram and QAMS by HPLC. The relative correction factor(RCF) was re-calculated and validated. The average RCFs of cinobufagin to gamabufotalin, bufotalin, bufalin and resibufogenin were considered for the determination of five bufadienolides in the samples. The total amount in the different batches of the dried samples varied from 4.06% to 17.0%. Referring to the revised methods for crude materials, the quality standard of toad venom powder was drafted including appearance description, TLC examination, characteristic chromatogram, water content and the total amount of five bufadienolides. The present investigation provided scientific evidences for the quality standard improvement of toad venom to be described in the next edition of Chinese pharmacopoeia(2020 edition).


Assuntos
Venenos de Anfíbios , Bufanolídeos , Animais , Bufonidae , Cromatografia Líquida de Alta Pressão , Pós , Controle de Qualidade
19.
Water Res ; 182: 115992, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32562960

RESUMO

Three different natural organic matter (NOM)-loading methods were compared for the adsorptive removal of 2-methylisoborneol (MIB) by superfine powdered activated carbon (SPAC) and conventionally-sized powdered activated carbon (PAC). The three NOM-loading methods were: NOM adsorption followed by MIB (MIB adsorption on NOM-preloaded carbon), MIB adsorption followed by NOM (MIB adsorption on NOM post-loaded carbon), and simultaneous NOM and MIB loading (MIB adsorption on NOM-simultaneously loaded carbon). MIB removals were similar for the smaller-sized carbon (SPAC) at higher AC dosages and at lower initial NOM concentrations. The similar MIB removals indicate direct site competition between MIB and NOM with MIB adsorption reversibility (complete desorption of MIB by NOM). At lower AC doses, especially for PACs, and at higher initial NOM concentrations, the adsorption of MIBs depended on the sequence of MIB or NOM adsorption. MIB removal was lowest for the NOM-preloaded carbon, followed by NOM-simultaneously loaded carbon. The highest MIB removal was achieved by post-loading of NOM, indicating that the adsorption is irreversible. MIB adsorption on SPAC was more reversible than on PAC, although the pore size distributions of the two carbons were similar. The high degree of adsorption irreversibility for PAC compared with SPAC indicated that pore blocking occurs due to NOM loading at the PAC particle surface. Images of the external adsorption were obtained using isotope mapping and 15N-labeled effluent organic matter.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Canfanos , Carvão Vegetal , Pós
20.
Minerva Stomatol ; 69(2): 106-111, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32489090

RESUMO

Alginic acid is a polysaccharide widely present in the cellular walls of brown algae. Alginate is widely used as a mold material in dentistry, in the production of prostheses and in the production of positives for small-scale casting. It is also used in the pharmaceutical, cosmetic and food industries for various uses. The purpose of our study is to assess whether the chemical and physical characteristics of water can influence the characteristics and performance of these materials. These impression materials are often marketed as a powder to be mixed with water, but water is not included during the purchase. We have considered different articles, but unfortunately the results that speak of this topic are few and contain little information. We have therefore carried out a review of the present literature on Pubmed and Embase search engine. The same product used by two people with two different waters will have different characteristics. The possibility of knowing these effects could allow for more performing materials and above all for identical and reproducible materials. In conclusions, the results indicate to follow the manufacturer's instructions, and eventually turn to the use of automatic devices.


Assuntos
Alginatos , Materiais para Moldagem Odontológica , Teste de Materiais , Pós
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