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1.
Sci Total Environ ; 888: 164088, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37201854

RESUMO

Environmental impact evaluation of buildings is critical for further analysis and optimization of pig farms for sustainable pork production. This study is the first attempt to quantify the carbon and water footprints of a standard intensive pig farm building using building information modeling (BIM) and operation simulation model. The model was constructed with carbon emission and water consumption coefficients, and a database was built. The results showed that the operational stage of pig farm accounted for most of the carbon footprint (49.3-84.9 %) and water footprint (65.5-92.5 %). Building materials production ranked second in carbon (12.0-42.5 %) and water footprints (4.4-24.9 %), and pig farm maintenance ranked third in carbon (1.7-5.7 %) and water footprints (0.7-3.6 %). Notably, the mining and production stages of building materials contributed the largest carbon and water footprints of pig farm construction. Masonry materials have a significant impact on the overall carbon and water footprints of the pig farm. Pig farm using aerated concrete could reduce 41.1 % of the total carbon footprint and 58.9 % of the total water footprint compared to that using coal gangue sintered brick and autoclaved fly ash brick. This study presented a BIM-enabled method for carbon and water footprint analysis of pig farms and illustrated how the model can be used to facilitate the low carbon design of agricultural buildings.


Assuntos
Pegada de Carbono , Carbono , Animais , Suínos , Fazendas , China , Água
2.
J Med Chem ; 65(16): 11241-11256, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35925768

RESUMO

Acute myelogenous leukemia (AML), a disease of the blood and bone marrow, is characterized by the inability of myeloblasts to differentiate into mature cell types. Dihydroorotate dehydrogenase (DHODH) is an enzyme well-known in the pyrimidine biosynthesis pathway; however, small molecule DHODH inhibitors were recently shown to induce differentiation in multiple AML subtypes. Using virtual screening and structure-based drug design approaches, a new series of N-heterocyclic 3-pyridyl carboxamide DHODH inhibitors were discovered. Two lead compounds, 19 and 29, have potent biochemical and cellular DHODH activity, favorable physicochemical properties, and efficacy in a preclinical model of AML.


Assuntos
Di-Hidro-Orotato Desidrogenase , Leucemia Mieloide Aguda , Di-Hidro-Orotato Desidrogenase/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico
3.
J Org Chem ; 86(23): 17482-17486, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34807596

RESUMO

Herein, a tandem approach that allows rapid access to the benzomorpholine scaffold is reported. This operationally simple method allows for valuable heterocycles to be isolated in moderate to high yields. The overall transformation consists of an initial C-N coupling, demonstrated using traditional Ullmann or Buchwald-Hartwig conditions, followed by an in situ oxetane ring opening. A range of functionality is tolerated on the aryl ring, and the cyclization exposes a pendant hydroxymethyl substituent, providing opportunities for further functionalization.


Assuntos
Aminação , Ciclização , Éteres Cíclicos
4.
Foods ; 9(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217998

RESUMO

To find an environmentally friendly and energy efficient alternative to acidic detergent for a milking system clean-in-place (CIP) process, this study investigated the feasibility of applying slightly acidic electrolyzed water (SAEW) alone to wash the system by cleaning soiled stainless steel (304) pipes, rubber gaskets, and PVC milk hoses, which were used in the milking system. The results showed that SAEW with appropriate parameters could achieve the same or even better hygienic effects compared with commercial detergent. Using response surface models, the SAEW parameters required to clean stainless steel were optimized at 9.9 min for the treatment time, 37.8 °C for the water temperature, and 60 mg/L for the available chlorine concentration; and were 14.4 min, 29.6 °C, and 60 mg/L for rubber gasket and PVC samples, respectively. After washing with the optimized parameter combination, bacteria and adenosine triphosphate on the three materials were almost non-detectable, indicating that SAEW has the potential to replace acidic detergents in CIP milking systems.

5.
Chem ; 6(3): 781-791, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32440572

RESUMO

A novel strategy employing cyclohexyl spectator ligands in Stille cross-coupling reactions has been developed as a general solution to the long-standing challenge of conducting stereospecific cross-coupling reactions at nitrogen-containing stereocenters. This method enables direct access to enantioenriched products that are difficult (or impossible) to obtain via alternative preparative methods. Selective and predictable transfer of a single secondary alkyl unit can be achieved under reaction conditions that exploit subtle electronic differences between activated and unactivated alkyl units. Through this approach, enantioenriched α-stannylated nitrogen-containing stereocenters undergo Pd-catalyzed arylation and acylation reactions with exceptionally high stereofidelity in all instances investigated. We demonstrate this process by using α-stannylated pyrrolidine, azetidine, and open-chain (benzylic and non-benzylic) nucleophiles in stereospecific reactions. This process will facilitate rapid and reliable access to enantioenriched compounds possessing nitrogen-substituted stereocenters, which constitute ubiquitous structural motifs in biologically active compounds emerging from the drug-discovery process.

6.
Sensors (Basel) ; 20(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316511

RESUMO

For all homoeothermic living organisms, heart rate (HR) is a core variable to control the metabolic energy production in the body, which is crucial to realize essential bodily functions. Consequently, HR monitoring is becoming increasingly important in research of farm animals, not only for production efficiency, but also for animal welfare. Real-time HR monitoring for humans has become feasible though there are still shortcomings for continuously accurate measuring. This paper is an effort to estimate whether it is realistic to get a continuous HR sensor for livestock that can be used for long term monitoring. The review provides the reported techniques to monitor HR of living organisms by emphasizing their principles, advantages, and drawbacks. Various properties and capabilities of these techniques are compared to check the potential to transfer the mostly adequate sensor technology of humans to livestock in term of application. Based upon this review, we conclude that the photoplethysmographic (PPG) technique seems feasible for implementation in livestock. Therefore, we present the contributions to overcome challenges to evolve to better solutions. Our study indicates that it is realistic today to develop a PPG sensor able to be integrated into an ear tag for mid-sized and larger farm animals for continuously and accurately monitoring their HRs.


Assuntos
Frequência Cardíaca/fisiologia , Gado , Monitorização Fisiológica/métodos , Bem-Estar do Animal , Animais , Eletrocardiografia/métodos , Fotopletismografia/métodos
7.
J Air Waste Manag Assoc ; 70(4): 379-392, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31990638

RESUMO

Particulate matter (PM) from poultry production facilities may strongly affect the health of animals and workers in the houses, and PM emitted to the ambient air is an important pollution source to the surrounding areas. Aviary system is considered as a welfare friendly production system for laying hens. However, its air quality is typically worse as compared with conventional cage systems, because of the higher PM concentration of indoor air and other airborne contaminants. Furthermore, PM's physical property, which has a direct impact on the penetration depth into the lungs of the birds and humans, is largely unknown for the aviary system. Therefore, a systematic method was utilized to investigate the characteristics of particles in the aviary house with large cage aviary unit system (LCAU) in Beijing, China. For the field measurements, three measuring locations were selected with two inside and one outside the house with LCAU to continuously monitor PM concentrations and collect the samples for particle size distribution (PSD) analysis. Results showed that PM2.5, PM10, and total suspended particulate (TSP) concentrations averaged at 0.037 ± 0.025 mg/m3, 0.42 ± 0.10 mg/m3, and 1.92 ± 1.91 mg/m3, respectively. Particle concentrations increased from October to December due to less ventilation as the weather got colder, and were generally affected by stocking density, ventilation rate, birds' activities, and housing system. Meanwhile, indoor PM2.5 concentration was easily impacted by the ambient air quality. Mass median diameter (MMD) and mass geometric standard deviation (MGSD) of the TSP during the measurement were 18.92 ± 7.08 µm and 3.11 ± 0.31, respectively. Count median diameter (CMD) and count geometric standard deviation (CGSD) were 1.94 ± 0.14 µm and 1.48 ± 0.08, respectively. Results indicated that the aviary system can attain a good indoor condition by suitable system design and environment control strategy.Implications: Indoor PM2.5 concentration of the layer house can be significantly affected by ambient air quality when the air quality index (AQI) was larger than 100. PM2.5 and PM10 concentrations of the layer house with a LCAU system were comparable to the cage system. TSP concentration was higher, and PM size was larger than most of the cage system. System design, larger space volume, and higher ventilation rate were the main influence factors. Good indoor environment of the aviary system can be achieved through the reasonable design of the production system and appropriate environment control strategy.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Galinhas , Abrigo para Animais , Material Particulado/análise , Animais , Pequim , Monitoramento Ambiental , Feminino , Tamanho da Partícula
8.
Sensors (Basel) ; 20(2)2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31947639

RESUMO

Heat stress is one of the most important environmental stressors facing poultry production and welfare worldwide. The detrimental effects of heat stress on poultry range from reduced growth and egg production to impaired health. Animal vocalisations are associated with different animal responses and can be used as useful indicators of the state of animal welfare. It is already known that specific chicken vocalisations such as alarm, squawk, and gakel calls are correlated with stressful events, and therefore, could be used as stress indicators in poultry monitoring systems. In this study, we focused on developing a hen vocalisation detection method based on machine learning to assess their thermal comfort condition. For extraction of the vocalisations, nine source-filter theory related temporal and spectral features were chosen, and a support vector machine (SVM) based classifier was developed. As a result, the classification performance of the optimal SVM model was 95.1 ± 4.3% (the sensitivity parameter) and 97.6 ± 1.9% (the precision parameter). Based on the developed algorithm, the study illustrated that a significant correlation existed between specific vocalisations (alarm and squawk call) and thermal comfort indices (temperature-humidity index, THI) (alarm-THI, R = -0.414, P = 0.01; squawk-THI, R = 0.594, P = 0.01). This work represents the first step towards the further development of technology to monitor flock vocalisations with the intent of providing producers an additional tool to help them actively manage the welfare of their flock.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Espectrografia do Som/métodos , Máquina de Vetores de Suporte , Vocalização Animal/fisiologia , Bem-Estar do Animal , Animais , Feminino , Transtornos de Estresse por Calor/prevenção & controle , Abrigo para Animais , Umidade , Processamento de Sinais Assistido por Computador , Temperatura
9.
Org Lett ; 21(23): 9642-9645, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31742420

RESUMO

Oxetanes have been increasingly used as stable motifs in medicinal chemistry as well as versatile synthetic intermediates. Herein, an intramolecular ring opening of oxetane carboxamides with mild nucleophiles, such as nitrogen heterocycles, is presented. The reaction proceeds under metal-free basic conditions which is highly unusual in ring opening reactions of oxetanes. Amide formation and oxetane ring opening/cyclization in a one-pot approach affords high levels of molecular complexity in a single step from simple, readily available substrates.

10.
J Air Waste Manag Assoc ; 69(2): 209-219, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30299214

RESUMO

As a convenient method, the closed chamber method has been applied to determine gaseous emission fluxes from fully open animal feeding operations despite the measured fluxes being theoretically affected by deployment time, wind speed over the emitting surface and detected gas mass. This laboratory study evaluated the effects of deployment time (0 to 120 min) and external surface wind speed (ESWS) (0.00, 0.25, 0.50, 0.75, 1.00, 1.50 and 2.00 m sec-1) on the measurement accuracy of a 300 mm (diameter) × 400 mm (height) (D300×H400) closed chamber using methane (CH4), nitrous oxide (N2O) and sulfur hexafluoride (SF6) as reference gases. The results showed that the overall deviation ratio between the measured and reference CH4 fluxes ranged from 9.99 % to -37.32 % and the flux was overestimated in the first 20 min. The measured N2O and SF6 emissions were smaller than the reference fluxes using the chamber. N2O measurement accuracy decreased from -14.47 to -35.09% with deployment time extended to 120 min, while SF6 accuracy sharply increased in the first 40 min, with the deviation stabilizing at approximately -5.00%. CH4, N2O and SF6 measurements were significantly affected by deployment time and ESWS (P<0.05), and the interaction of those two factors greatly influenced CH4 and SF6 measurements (P<0.05). With the D300×H400 closed chamber, deployment times of 20 to 30 min and 10 to 20 min are recommended to measure CH4 and N2O, respectively, from the open operations of dairy farms under wind speeds lower than 2 m sec-1. Implications: This study recommended the suitable deployment times and wind speeds for using a D300 × H400 closed chamber to measure CH4, N2O, and SF6 in an open system, such as a dairy open lot and manure stockpile, to help researchers and other related industry workers get accurate data for gas emission rate. Deployment times of 20 to 30 min and 10 to 20 min were recommended to measure CH4 and N2O emissions using the D300 × H400 closed chamber, respectively, from the open operations of dairy farms under wind speeds lower than 2 m sec-1. For the measurement of SF6, a typical tracer gas, a deployment of 70 to 90 min was suggested.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Gases de Efeito Estufa/análise , Vento , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Animais , Dióxido de Carbono/análise , Precisão da Medição Dimensional , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Humanos , Metano/análise , Óxido Nitroso/análise , Fatores de Tempo
11.
Angew Chem Int Ed Engl ; 56(3): 856-860, 2017 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-27981696

RESUMO

We report the development of a Pd-catalyzed process for the cross coupling of unactivated primary, secondary, and tertiary alkylcarbastannatrane nucleophiles with acyl electrophiles. Reactions involving optically active alkylcarbastannatranes occur with exceptional stereofidelity and with net retention of absolute configuration. Because the stereochemistry of the resulting products is entirely reagent-controlled, this process may be viewed as a general, alternative approach to the preparation of products typically accessed via asymmetric enolate methodologies. Additionally, we report a new method for the preparation of optically active alkylcarbastannatranes, which should facilitate their future use in stereospecific reactions.


Assuntos
Compostos Organometálicos/síntese química , Paládio/química , Acilação , Catálise , Estrutura Molecular , Compostos Organometálicos/química , Estereoisomerismo
12.
J Asian Nat Prod Res ; 18(11): 1091-100, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27285735

RESUMO

HepG2 cells were induced with a high concentration of insulin to establish an insulin-resistant cell model (HepG2/IR). The effect of 12b-hydroxy-des-D-garcigerin A (DGA) on the glucose consumption (GC) of HepG2/IR cells was analyzed with the glucose oxidase/peroxidase assay. The results showed that DGA significantly stimulated GC by enhancing the activity of hexokinase (HK) and pyruvate kinase (PK) in HepG2/IR cells. The cell signaling pathway by which DGA enhances the GC of HepG2/IR cells was explored. The results showed that DGA promoted the expression of insulin receptor (InsR) protein, and stimulated the expression of insulin receptor substrate 1 (IRS-1), phosphatidylinositol-3 kinase (p-PI3-K), and phospho-protein kinase B Serine(473) (p-AKT ser(473)). Therefore, we concluded that DGA improved the insulin-resistance of HepG2/IR cells by inducing the IRS-1/PI3-K/Akt cell signaling pathway. Interestingly, DGA had no effect on the phosphorylation of threonine(172) (Thr(172)) in AMP-activated protein kinase (AMPK).


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antifúngicos/farmacologia , Xantonas/farmacologia , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Modelos Animais de Doenças , Glucose/metabolismo , Células Hep G2 , Humanos , Proteínas Substratos do Receptor de Insulina , Resistência à Insulina , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Reação em Cadeia da Polimerase , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Xantonas/química , Xantonas/isolamento & purificação
13.
J Air Waste Manag Assoc ; 66(7): 715-25, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27045675

RESUMO

UNLABELLED: To investigate the impacts of major factors on carbon loss via gaseous emissions, carbon dioxide (CO2) and methane (CH4) emissions from the ground of open dairy lots were tested by a scale model experiment at various air temperatures (15, 25, and 35 °C), surface velocities (0.4, 0.7, 1.0, and 1.2 m sec(-1)), and floor types (unpaved soil floor and brick-paved floor) in controlled laboratory conditions using the wind tunnel method. Generally, CO2 and CH4 emissions were significantly enhanced with the increase of air temperature and velocity (P < 0.05). Floor type had different effects on the CO2 and CH4 emissions, which were also affected by air temperature and soil characteristics of the floor. Although different patterns were observed on CH4 emission from the soil and brick floors at different air temperature-velocity combinations, statistical analysis showed no significant difference in CH4 emissions from different floors (P > 0.05). For CO2, similar emissions were found from the soil and brick floors at 15 and 25 °C, whereas higher rates were detected from the brick floor at 35 °C (P < 0.05). Results showed that CH4 emission from the scale model was exponentially related to CO2 flux, which might be helpful in CH4 emission estimation from manure management. IMPLICATIONS: Gaseous emissions from the open lots are largely dependent on outdoor climate, floor systems, and management practices, which are quite different from those indoors. This study assessed the effects of floor types and air velocities on CO2 and CH4 emissions from the open dairy lots at various temperatures by a wind tunnel. It provided some valuable information for decision-making and further studies on gaseous emissions from open lots.


Assuntos
Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Indústria de Laticínios , Metano/análise , Modelos Teóricos , Esterco , Solo/química , Temperatura
14.
J Air Waste Manag Assoc ; 66(3): 267-79, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26891681

RESUMO

UNLABELLED: The open lots and manure stockpiles of dairy farm are major sources of greenhouse gas (GHG) emissions in typical dairy cow housing and manure management system in China. GHG (CO(2), CH(4) and N(2)O) emissions from the ground level of brick-paved open lots and uncovered manure stockpiles were estimated according to the field measurements of a typical dairy farm in Beijing by closed chambers in four consecutive seasons. Location variation and manure removal strategy impacts were assessed on GHG emissions from the open lots. Estimated CO(2), CH(4) and N(2)O emissions from the ground level of the open lots were 137.5±64.7 kg hd(-1) yr(-1), 0.45±0.21 kg hd(-1) yr(-1) and 0.13±0.08 kg hd(-1) yr(-1), respectively. There were remarkable location variations of GHG emissions from different zones (cubicle zone vs. aisle zone) of the open lot. However, the emissions from the whole open lot were less affected by the locations. After manure removal, lower CH(4) but higher N(2)O emitted from the open lot. Estimated CO(2), CH(4) and N(2)O emissions from stockpile with a stacking height of 55±12 cm were 858.9±375.8 kg hd(-1) yr(-1), 8.5±5.4 kg hd(-1) yr(-1) and 2.3±1.1 kg hd(-1) yr(-1), respectively. In situ storage duration, which estimated by manure volatile solid contents (VS), would affect GHG emissions from stockpiles. Much higher N(2)O was emitted from stockpiles in summer due to longer manure storage. IMPLICATIONS: This study deals with greenhouse gas (GHG) emissions from open lots and stockpiles. It's an increasing area of concern in some livestock producing countries. The Intergovernmental Panel on Climate Change (IPCC) methodology is commonly used for estimation of national GHG emission inventories. There is a shortage of on-farm information to evaluate the accuracy of these equations and default emission factors. This work provides valuable information for improving accounting practices within China or for similar manure management practice in other countries.


Assuntos
Poluentes Atmosféricos/química , Indústria de Laticínios , Monitoramento Ambiental/métodos , Gases , Esterco/análise , Animais , Dióxido de Carbono/análise , Bovinos , China , Efeito Estufa , Metano/análise , Nitratos/análise , Óxido Nitroso/análise , Oxigênio/análise , Estações do Ano , Eliminação de Resíduos Líquidos/métodos
15.
Chem Sci ; 6(9): 5105-5113, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26388985

RESUMO

Several research groups have recently developed methods to employ configurationally stable, enantioenriched organometallic nucleophiles in stereospecific Pd-catalyzed cross-coupling reactions. By establishing the absolute configuration of a chiral alkyltin or alkylboron nucleophile prior to its use in cross-coupling reactions, new stereogenic centers may be rapidly and reliably generated with preservation of the known initial stereochemistry. While this area of research is still in its infancy, such stereospecific cross-coupling reactions may emerge as simple, general methods to access diverse, optically active products from common enantioenriched organometallic building blocks. This minireview highlights recent progress towards the development of general, stereospecific Pd-catalyzed cross-coupling reactions using configurationally stable organometallic nucleophiles.

16.
J Environ Manage ; 161: 402-407, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26209762

RESUMO

Water pollution causes substantial damage to the environment and to human health, and the current methods to treat pollution suffer from high cost and low efficiency, resulting in increased environmental damages. Using genetic modification and functional selection, we developed a novel biosorbent from Genetically Engineered Bacillus subtilis (GEBS) cells. At a ratio of biosorbent to direct blue dye of about 1:1.25 in a water solution, the dye pigments can be completely adsorbed in 40 s, decreasing COD to zero. Contrary to other biosorbents, ions such as Fe(2+) and Cu(2+) have significant advantages in terms of the adsorbing efficiency. The GEBS biomass can therefore capture both organics and ions from wastewater simultaneously and achieve co-precipitation in 2-10 min, which are features critical for practical applications of wastewater treatment. In addition, we used six different eluting solutions to regenerate used biomass, all resulting in renewed, highly efficient color and COD elimination capacities, with the best elution solution being NaHCO3 and Na2CO3. For practical applications, we showed a high COD elimination rate when using the GEBS biomass to treat raw water from textile enterprises, paper mill, and petrochemical industries. Compared with currently available adsorbing agents, the GEBS cells can adsorb organic and ion waste much faster and with much higher efficiency, can be regenerated and recycled efficiently, and may have broad applications in treating organic water pollution.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Engenharia Genética , Águas Residuárias/microbiologia , Adsorção/fisiologia , Biomassa , Resíduos Industriais , Íons , Reciclagem , Poluentes Químicos da Água/análise
17.
J Asian Nat Prod Res ; 16(10): 991-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24930917

RESUMO

Glycoborinine (GB), a natural carbazole alkaloid isolated from Glycosmis pentaphylla, has been shown to be a potential molecule against cancer cells. In this study, the cell-signaling pathway of its anti-tumor activity was investigated. MTT assay result showed that GB inhibited HepG2 cell proliferation in a dose- and time-dependent manner and 50% inhibiting concentration (IC50) of GB-induced cell death was 39.7 µM for a period of 48 h. GB-induced HepG2 apoptosis was confirmed by Hochest 33258 staining and PI staining. The level of reactive oxygen species (ROS) was measured with H2DCF-DA staining and the change of mitochondrial membrane potential (△Ψ(m)) was analyzed with tetrechloro-tetraethylbenzimidazolcarbocyanine iodide (JC-1) probe. Results showed that GB at 12.5, 25, and 50 µM promoted ROS production. GB induced HepG2 apoptosis through a mitochondrial apoptotic pathway, which was demonstrated by GB-induced increase in the ratio of Bax/Bcl-2, cytochrome C release, the ratio of cleaved caspase-3/procaspase-3, and the ratio of cleaved poly ADP-ribose polymerase (cleaved PARP)/poly ADP-ribose polymerase (PARP). To summarize, this study demonstrated that GB could induce HepG2 apoptosis through the mitochondrial-dependent pathway, which might provide a promising approach to cure liver cancer with GB.


Assuntos
Apoptose/efeitos dos fármacos , Carbazóis/farmacologia , Benzimidazóis , Carbazóis/química , Carbocianinas , Caspase 3/metabolismo , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/metabolismo , Potencial da Membrana Mitocondrial , Estrutura Molecular , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
18.
J Air Waste Manag Assoc ; 64(4): 494-500, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24843920

RESUMO

UNLABELLED: Reducing airborne microorganisms may potentially improve the environment in layer breeding houses. The effectiveness of slightly acidic electrolyzed water (SAEW; pH 5.29-6.30) in reducing airborne microorganisms was investigated in a commercial layer house in northern China. The building had a tunnel-ventilation system, with an evaporative cooling. The experimental area was divided into five zones along the length of the house, with zone 1 nearest to an evaporative cooling pad and zone 5 nearest to the fans. The air temperature, relative humidity, dust concentration, and microbial population were measured at the sampling points in the five zones during the study period. The SAEW was sprayed by workers in the whole house. A six-stage air microbial sampler was used to measure airborne microbial population. Results showed that the population of airborne bacteria and fungi were sharply reduced by 0.71 x 10(5) and 2.82 x 10(3) colony-forming units (CFU) m(-3) after 30 min exposure to SAEW, respectively. Compared with the benzalkonium chloride (BC) solution and povidone-iodine (PVP-I) solution treatments, the population reductions of airborne fungi treated by SAEW were significantly (P < 0.05) more, even though the three disinfectants can decrease both the airborne bacteria and fungi significantly (P < 0.05) 30 min after spraying. IMPLICATIONS: There are no effective methods for reducing airborne microbial levels in tunnel-ventilated layer breeding houses; additionally, there is limited information available on airborne microorganism distribution. This research investigated the spatial distribution of microbial population, and the effectiveness of spraying slightly acidic electrolyzed water in reducing microbial levels. The research revealed that slightly acidic electrolyzed water spray was a potential method for reducing microbial presence in layer houses. The knowledge gained in this research about the microbial population variations in the building may assist producers in managing the bird housing environment and engineers in designing poultry houses.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/prevenção & controle , Desinfetantes/química , Desinfecção/métodos , Abrigo para Animais , Peróxido de Hidrogênio/química , Ácidos/química , Poluição do Ar em Ambientes Fechados/análise , Animais , Antibacterianos/química , Antifúngicos/química , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Compostos de Benzalcônio , China , Contagem de Colônia Microbiana , Poeira/análise , Monitoramento Ambiental , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Umidade , Aves Domésticas , Povidona-Iodo , Temperatura
19.
J Solution Chem ; 42: 2342-2353, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24319302

RESUMO

Solubility data were measured for omeprazole sulfide in ethanol, 95 mass-% ethanol, ethyl acetate, isopropanol, methanol, acetone, n-butanol and n-propanol in the temperature range from 280.35 to 319.65 K by employing the gravimetric method. The solubilities increase with temperature and they are in good agreement with the calculated solubility of the modified Apelblat equation and the λh equation. The experimental solubility and correlation equation in this work can be used as essential data and model in the purification process of omeprazole sulfide. The thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated using the van't Hoff equation.

20.
Nat Chem ; 5(7): 607-12, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23787752

RESUMO

The development of transition metal-catalysed cross-coupling reactions has greatly influenced the manner in which the synthesis of complex organic molecules is approached. A wide variety of methods are now available for the formation of C(sp(2))-C(sp(2)) bonds, and more recent work has focused on the use of C(sp(3)) electrophiles and nucleophiles. The use of secondary and tertiary alkyl nucleophiles in cross-coupling reactions remains a challenge because of the propensity of these alkyl groups to isomerize under the reaction conditions. Here, we report the development of a general Pd-catalysed process for the stereoretentive cross-coupling of secondary alkyl azastannatrane nucleophiles with aryl chlorides, bromides, iodides and triflates. Coupling partners with a wide range of electronic characteristics are well tolerated. The reaction occurs with minimal isomerization of the secondary alkyltin nucleophile, and with retention of absolute configuration. This process constitutes the first general method to use secondary alkyltin reagents in cross-coupling reactions.


Assuntos
Halogênios/química , Paládio/química , Compostos de Estanho/química , Catálise , Estereoisomerismo
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