Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 193
Article in Chinese | WPRIM | ID: wpr-928125


In view of the longevity and innate immune escape of red blood cells, this study designed the red blood cell membrane-coated paclitaxel nanosuspension [RBC-(PTX)NS] and investigated its physicochemical properties and antitumor effect in vitro. Paclitaxel nanosuspension [(PTX)NS] was prepared by ultrasonic precipitation and then RBC-(PTX)NS by ultrasonic coating. The formulation of(PTX)NS was optimized with Box-Behnken method and indexes of particle diameter, zeta potential, and stability. The morphology, particle diameter, stability, in vitro dissolution, and antitumor effect of(PTX)NS and RBC-(PTX)NS were characterized. The results showed that the particle diameter and zeta potential were(129.38±0.92) nm and(-22.41±0.48) mV, respectively, for the optimized(PTX)NS, while(142.5±0.68) nm and(-29.85±0.53) mV, respectively, for RBC-(PTX)NS. Under the transmission electron microscope,(PTX)NS was spherical and RBC-(PTX)NS had obvious core-shell structure. RBC-(PTX)NS remained stable for 5 days at 4 ℃. The in vitro dissolution test demonstrated that the cumulative release rate of RBC-(PTX)NS reached 79% within 20 min, which was significantly higher than that(25%) of(PTX)NS(P<0.05). As evidenced by MTT assay, RBC-(PTX)NS highly inhibited the proliferation of HepG2 cells in a dose-dependent manner. The cell membrane-coated nano-preparation preparation method is simple and reproducible. It improves the solubility of PTX and endows RBC-(PTX)NS with higher stability and stronger cytotoxicity. Thus, it is a new method for the delivery of PTX via nanocrystallization.

Erythrocyte Membrane , Nanoparticles/chemistry , Paclitaxel/pharmacology , Particle Size , Suspensions
Chinese Journal of Biotechnology ; (12): 506-517, 2022.
Article in Chinese | WPRIM | ID: wpr-927724


Microbial induced calcium carbonate precipitation (MICP) refers to the natural biological process of calcium carbonate precipitation induced by microbial metabolism in its surrounding environment. Based on the principles of MICP, microbial cement has been developed and has received widespread attention in the field of biology, civil engineering, and environment owing to the merits of environmental friendliness and economic competence. Urease and carbonic anhydrase are the key enzymes closely related to microbial cement. This review summarizes the genes, protein structures, regulatory mechanisms, engineering strains and mutual synergistic relationship of these two enzymes. The application of bioinformatics and synthetic biology is expected to develop biocement with a wide range of environmental adaptability and high performance, and will bring the MICP research to a new height.

Calcium Carbonate/metabolism , Chemical Precipitation , Urease/metabolism
Braz. J. Pharm. Sci. (Online) ; 58: e18800, 2022. tab, graf, ilus
Article in English | LILACS | ID: biblio-1364431


Abstract Efavirenz is one of the most commonly used drugs in HIV therapy. However the low water solubility tends to result in low bioavailability. Drug nanocrystals, should enhance the dissolution and consequently bioavailability. The aim of the present study was to obtain EFV nanocrystals prepared by an antisolvent technique and to further observe possible effect, on the resulting material, due to altering crystallization parameters. A solution containing EFV and a suitable solvent was added to an aqueous solution of particle stabilizers, under high shear agitation. Experimental conditions such as solvent/antisolvent ratio; drug load; solvent supersaturation; change of stabilizer; addition of milling step and solvents of different polarities were evaluated. Suspensions were characterized by particle size and zeta potential. After freeze- dried and the resulting powder was characterized by PXRD, infrared spectroscopy and SEM. Also dissolution profiles were obtained. Many alterations were not effective for enhancing EFV dissolution; some changes did not even produced nanosuspensions while other generated a different solid phase from the polymorph of raw material. Nevertheless reducing EFV load produced enhancement on dissolution profile. The most important modification was adding a milling step after precipitation. The resulting suspension was more uniform and the powder presented grater enhancement of dissolution efficacy.

Efficacy/classification , HIV/pathogenicity , Crystallization/instrumentation , Dissolution/methods , Particle Size , Solubility , Pharmaceutical Preparations/administration & dosage , Excipients/pharmacology , Dissolution/classification , Nanoparticles/administration & dosage , Methods
Braz. J. Pharm. Sci. (Online) ; 58: e191042, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394057


Abstract L-Asparaginase (L-ASNase) is a biopharmaceutical used for acute lymphoblastic leukaemia (ALL) treatment, dramatically increasing the patients' chance of cure. However, its production and distribution in developing countries were disrupted because of its low profitability, which caused great concern among patients. This study evaluates the feasibility of combining fractional precipitation and aqueous two-phase systems (ATPS) to purify L-ASNase from a low-grade product, commercially known as Acrylaway® L. The ATPS purification results were not particularly expressive compared to the two-step purification process composed of ethanol precipitation and gel filtration, which was able to recover the target molecule with a purification factor over 5 fold. Thus, we studied a purification process capable of manufacturing pharmaceutical grade L-ASNase from a commercially available low-grade raw material; however, improvements regarding its throughput must be achieved, and high purity is the first step to apply it as a new biopharmaceutical product. The proposed process could pose as a short-time solution to mitigate its shortage while a cost-effective production plant is being developed.

Asparaginase/isolation & purification , Fractional Precipitation/methods , Antineoplastic Agents/isolation & purification , Feasibility Studies , Chromatography, Gel , Cost-Benefit Analysis
Med. leg. Costa Rica ; 38(2)dic. 2021.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1386289


Resumen Introducción: La crisis por la Covid-19, en muchas maneras, podría exacerbar ciertas dimensiones del proceso suicida a través de su impacto psicológico, social, económico o, incluso, biológico. El estudio comparará los casos de suicidio por ahorcadura, precipitación e intoxicación atendidos en la morgue judicial de la provincia de Panamá, entre marzo del 2019 a febrero del 2020 y marzo del 2020 a febrero del 2021. Material y métodos: Se trata de un estudio descriptivo, transversal y retrospectivo; cuya población de análisis comprende todas las autopsias médico-legales realizadas en la Morgue Judicial de Panamá por casos de ahorcadura, precipitación e intoxicación, de marzo del 2019 a febrero del 2021. Resultados: En el estudio se registró un total de 117 casos. De estos, 73 practicados de marzo del 2019 a febrero del 2020, de los cuales el 78 % (n=57) correspondió al sexo masculino, con una media de 41 años, y el 22 % (n=16) al sexo femenino, con una media de 36 años; mientras que, en el lapso de marzo del 2020 a febrero del 2021 la muestra fue de 44 casos, lo que representó el 93 % (n=41), de sexo masculino, con una media de 42 años y el 7 % (n=3) de sexo femenino, con una media de 47 años. Conclusión: Durante el año posterior al inicio de la pandemia y la aplicación de las medidas de cuarentena en la provincia de Panamá hubo una disminución de la frecuencia de los casos de suicidios por ahorcadura e intoxicación en comparación con el año previo y un aumento en cuanto a los casos por precipitación.

Abstract Introduction: The Covid-19 crisis in many ways could exacerbate certain dimensions of the suicidal process through its psychological, social, economic or even biological impact. In this study we will compare the cases of suicide by hanging, precipitation and intoxication carried out in the Judicial Morgue of Ancon from March 2019 to February 2020 and from March 2020 to February 2021. Materials and methods: This is a descriptive, cross-sectional and retrospective study; the population studied will be all the medicolegal autopsies performed in the Judicial Morgue of Panama, due to hanging, precipitation and intoxication in the period from March 2019 to February 2021. Results: A total of 117 cases were recorded in this period studied; 73 cases from March 2019 to February 2020 of which 78% (n=57) corresponded to the male sex, with an average of 41 years and 22% (n=16) to the female sex, with an average of 36; while, in the period from March 2020 to February 2021, of the sample of 44 cases 93% (n=41) corresponded to the male sex, with an average of 42 and 7% (n=3) to the female sex, with an average of 47 years. Conclusión: During the year after the beginning of the pandemic and the quarantine measures in the Province of Panama, there was a decrease in the frequency of suicide cases by hanging, precipitation and intoxication compared to the previous year.

Rev. colomb. quím. (Bogotá) ; 50(2): 49-57, mayo-ago. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1341316


Resumen Se determinaron las condiciones más favorables para la síntesis de hidróxido de níquel (II) por precipitación química a partir de la disolución lixiviada del sulfuro de níquel de la tecnología Caron. La disolución lixiviada de fuerza iónica igual a 4,6 mol-L-1 fue tratada con hidróxidos de amonio y sodio. Se calcularon las propiedades termodinámicas como entalpía, entropía y energía libre y se construyeron diagramas de zona de predominancia. Se demostró la conveniencia de realizar el proceso a 303 K, pH entre 11 y13 y concentración de amoníaco de 0,5 a 1,0 mol•L-1. En estas condiciones fueron obtenidas altas eficiencias de precipitación de los cationes metálicos de la disolución inicial. El sólido precipitado se caracterizó mediante espectrometría de absorción atómica y difracción de rayos X. Se obtuvo un beta-hidróxido de níquel (II) con la siguiente composición química: 58,5 ≤ Ni ≤ 59,1%, 1,7 ≤ Co ≤ 2,1%, 0,5 ≤ Fe ≤ 0,6%, Cu, Zn, Mn y Mg ≤ 0,2%.

Abstract The most favorable conditions for the synthesis of nickel (II) hydroxide were determined by chemical precipitation, from the leached solution of nickel sulfide from the Caron technology. The leached solution with an ionic strength equal to 4.6 mol-L-1 was treated with ammonium and sodium hydroxides. Thermodynamic properties such as enthalpy, entropy, and free energy were calculated and predominance zone diagrams were constructed. The convenience of performing the process at 303 K, pH between 11 and 13, and ammonia concentration of 0.5 to 1.0 mol•L-1 was demonstrated. Under these conditions, high precipitation efficiencies of the metal cations from the initial solution were obtained. The precipitated solid was characterized by atomic absorption spectrometry and X-ray diffraction. Nickel (II) beta-hydroxide with the following chemical composition was obtained: 58.5 ≤ Ni ≤ 59.1%, 1.7 ≤ Co ≤ 2.1%, 0.5 ≤ Fe ≤ 0.6%, Cu, Zn, Mn and Mg ≤ 0.2%.

Resumo As condições mais favoráveis para a síntese do hidróxido de níquel (II) foram determinadas por precipitação química, a partir da solução lixiviada de sulfeto de níquel da tecnologia Caron. A solução lixiviada de força iônica igual a 4,6 mol-L-1, foi tratada com hidróxidos de amônio e sódio. Foram calculadas propriedades termodinâmicas, como entalpia, entropia e energia livre, e diagramas de zonas de predominância foram construídos. Foi demonstrada a conveniência de realizar o processo a 303 K, pH entre 11 e 13 e concentração de amônia de 0,5 a 1,0 mol•L-1. Nessas condições, foram obtidas altas eficiências de precipitação dos cátions metálicos da solução inicial. O sólido precipitado foi caracterizado por espectrometria de absorção atômica e difração de raios-x. Foi obtido beta-hidróxido de níquel (II) com a seguinte composição química: 58,5 ≤ Ni ≤ 59,1%, 1,7 ≤ Co ≤ 2,1%, 0,5 ≤ Fe ≤ 0,6%, Cu , Zn, Mn e Mg ≤ 0,2%.

Eng. sanit. ambient ; 26(2): 339-349, Mar.-Apr. 2021. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1249751


RESUMO A Bacia Hidrográfica do Rio Paraíba do Sul foi afetada por uma das secas mais severas de sua história, durante os anos de 2013 a 2015, que resultou em várias consequências para o gerenciamento de seus recursos hídricos. O objetivo deste artigo foi contribuir com o entendimento desse evento histórico, no trecho Paulista da Bacia do Rio Paraíba do Sul, por meio do cálculo e da análise do índice padronizado de precipitação. Esse índice foi calculado nas escalas de 1, 3, 6 e 12 meses, para 22 estações pluviométricas localizadas na área de estudo. Os resultados demonstraram que a seca ocorrida entre 2013 e 2014 foi uma das mais severas já registradas, e que o verão de 2014 foi o período crítico no que diz respeito à redução da chuva regional. Essa seca impactou o armazenamento e a capacidade de regularização do principal reservatório da região, o Reservatório de Paraibuna. Embora o pico da crise hídrica tenha ocorrido, principalmente, em razão da seca de 2013/2014, verificou-se que ele foi influenciado pelo efeito cumulativo de uma seca anterior, ocorrida desde o início do ano de 2011. Esse resultado reforça a importância do planejamento plurianual da operação do Sistema Hidráulico da Bacia do Rio Paraíba do Sul.

ABSTRACT The Paraiba do Sul River Basin was affected by one of the most severe drought periods in its recent history, during the years 2013 to 2015, which resulted in several consequences for the management of its water resources. This article aims to contribute to the understanding of this historical event in the São Paulo Stretch of the Paraiba do Sul River Basin, through the calculation and analysis of the standardized precipitation index (SPI). SPI was calculated for the time scales of 1, 3, 6, and 12 months, for 22 rainfall stations located in the study area. The results showed that the drought occurred between 2013 and 2014 was one of the most severe ever recorded, and that the summer of 2014 was the critical period in terms of reduction of regional rainfall. This drought impacted the storage and regularization capacity of the main reservoir of the region, the Paraibuna Reservoir. Although the peak of the water crisis occurred mainly due to the 2013/2014 drought, it was found that it was influenced by the cumulative effect of a previous dry period, that occurred since the beginning of the year of 2011. This result reinforces the importance of multiannual planning for the operation of the Paraíba do Sul River Basin Hydraulic System.

Chinese Journal of Biotechnology ; (12): 4102-4110, 2021.
Article in Chinese | WPRIM | ID: wpr-921491


The abundance of proteins in human urine is low and easily to be masked by high-abundance proteins during mass spectrometry analysis. Development of efficient and highly selective enrichment methods is therefore a prerequisite for achieving deep coverage of urine protein markers. Notably, different experimental methods would affect the urine protein enrichment efficacy and the coverage of urine proteome. In this study, ultrafiltration, nitrocellulose membrane enrichment and saturated ammonium sulfate precipitation were used to process 10 mL urine samples from five healthy volunteers and five bladder cancer patients. The urine proteins were enriched and separate by SDS-PAGE to compare the purification efficiency of different methods. Moreover, the peptide identification effects of different purification methods were analyzed by mass spectrometry to determine the best method for enriching urine protein histones. Saturated ammonium sulfate precipitation method outperformed the ultrafiltration and the nitrocellulose membrane enrichment methods in terms of the protein enrichment efficacy and quality. The interference of highly abundant albumin was reduced, whereas the amount of low-abundance protein was increased, and the sensitivity of mass spectrometry identification was increased. The saturated ammonium sulfate precipitation method may be applied for large-scale urine processing for screening clinical diagnostic markers through proteomics.

Histones , Humans , Mass Spectrometry , Proteome , Proteomics , Urinalysis
Acta Pharmaceutica Sinica B ; (6): 2880-2899, 2021.
Article in English | WPRIM | ID: wpr-888892


Aberrant activation of NLRP3 inflammasome in colonic macrophages strongly associates with the occurrence and progression of ulcerative colitis. Although targeting NLRP3 inflammasome has been considered to be a potential therapy, the underlying mechanism through which pathway the intestinal inflammation is modulated remains controversial. By focusing on the flavonoid lonicerin, one of the most abundant constituents existed in a long historical anti-inflammatory and anti-infectious herb

Acta Pharmaceutica Sinica B ; (6): 2585-2604, 2021.
Article in English | WPRIM | ID: wpr-888873


Invasive fungal infections (IFIs) represent a growing public concern for clinicians to manage in many medical settings, with substantial associated morbidities and mortalities. Among many current therapeutic options for the treatment of IFIs, amphotericin B (AmB) is the most frequently used drug. AmB is considered as a first-line drug in the clinic that has strong antifungal activity and less resistance. In this review, we summarized the most promising research efforts on nanocarriers for AmB delivery and highlighted their efficacy and safety for treating IFIs. We have also discussed the mechanism of actions of AmB, rationale for treating IFIs, and recent advances in formulating AmB for clinical use. Finally, this review discusses some practical considerations and provides recommendations for future studies in applying AmB for combating IFIs.

Acta Pharmaceutica Sinica B ; (6): 2505-2536, 2021.
Article in English | WPRIM | ID: wpr-888870


Amorphous solid dispersions (ASDs) are popular for enhancing the solubility and bioavailability of poorly water-soluble drugs. Various approaches have been employed to produce ASDs and novel techniques are emerging. This review provides an updated overview of manufacturing techniques for preparing ASDs. As physical stability is a critical quality attribute for ASD, the impact of formulation, equipment, and process variables, together with the downstream processing on physical stability of ASDs have been discussed. Selection strategies are proposed to identify suitable manufacturing methods, which may aid in the development of ASDs with satisfactory physical stability.

Acta Pharmaceutica Sinica ; (12): 2112-2118, 2021.
Article in Chinese | WPRIM | ID: wpr-887061


Ma-Xing-Shi-Gan Decoction is a classic prescription. However, the interaction among multiple components of the decoction and the change of phase state are not clear. Moreover, the relationship between the physical phase state aggregated by multiple components and the efficacy still needs to be studied. In this study, we monitored the particle size changes of Ma-Xing-Shi-Gan Decoction in real time. Then we isolated different phase states by centrifugation, analyzed their composition distribution and tested their antibacterial activity. We added chemical interference agents to investigate the interaction of multi-component physical phase states accompanied by the observation of particle size change and morphology. We also studied the correlation between antibacterial activity and physical structure of phase states. The results showed during boiling process the degree of hybridization of particles was decreased and the particle size distribution was narrowed and stabilized at 170 nm. The distribution of organic and inorganic components was heterogeneous among different phase states. S-13500, supernatant isolated by 13 500 ×g centrifugation, constituted by ephedrine, amygdalin, glycyrrhizic acid and inorganic components Ca, K, Mg, etc., had the strongest antibacterial activity. The molecular interaction force in the active physical phase state was mainly hydrophobic and hydrogen bond. The destruction of the interaction force will lead to the change of phase structure and the decrease of antibacterial activity in vitro and in vivo. This study confirms that, in the boiling process of the Ma-Xing-Shi-Gan Decoction, the chemical components interweave and interact to form new physical phase states, leading to heterogeneous distribution of components. The antimicrobial activity of the active phase depends on both chemical composition and physical structure, which provides a direct evidence for the physical basis of the efficacy of traditional Chinese medicine.

Rev. colomb. biotecnol ; 22(2): 53-69, jul.-dic. 2020. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1156288


RESUMEN El Drenaje ácido de mina (DAM) es actualmente el principal contaminante de las regiones mineras. Los reactores bioquímicos pasivos son una tecnología sostenible fácil de instalar que utiliza desechos agroindustriales de la región y puede operar en áreas remotas con poco mantenimiento. Además, son una tecnología limpia que involucra bioprocesos, reacciones químicas y precipitación de metales, minimizando el impacto de los vertimientos ácidos sobre suelos y cuerpos de aguas. Los reactores bioquímicos pasivos son columnas empacadas con una "mezcla reactiva" conformada por materiales orgánicos, inorgánicos y un inóculo microbiano. En esta mezcla se remedia el DAM por medio de procesos fisicoquímicos como la adsorción, precipitación, coprecipitación de los metales y de la reducción del sulfato a sulfuro, mientras se incrementa el pH y la alcalinidad. Con el fin de brindar información reciente, así como las necesidades de investigación en el tema, este documento presenta una revisión de literatura sobre la generación química y biológica de los DAM, así como su remedición utilizando reactores bioquímicos pasivos. El conocimiento de los conceptos básicos de estos procesos es extremadamente útil para evaluar las posibles aplicaciones, beneficios y limitaciones de estos sistemas de tratamiento utilizados por la biotecnología durante la biorremediación de efluentes mineros.

ABSTRACT Acid Mine Drainage (AMD) is currently the main pollutant in mining areas. Passive biochemical reactors are a sustainable technology easy to install using agro-industry waste from the mining region and operating in remote locations. Besides, bioreactors are clean technology that involves bioprocesses, chemical reactions, and metal precipitation, minimizing the impact of AMD on soils and fresh water sources. The passive biochemical reactors are columns packed with a "reactive mixture" consisting of organic, inorganic materials and a microbial inoculum. In this reactive mixture, AMD is remediated through physicochemical processes such as metals adsorption, precipitation, and co-precipitation, as well as, the reduction of sulfate to sulfur, while pH and alkalinity are in-creased. To provide recent information and research needs in the subject, this document presents a review of the literature about the chemical and biological generation of AMD and its remediation using passive biochemical reactors. The knowledge of the basic concepts of these processes is extremely useful to evaluate the possible applications, benefits and limitations of these treatment systems used by biotechnology during the bioremediation of mining effluents.

Biosci. j. (Online) ; 36(6): 2050-2059, 01-11-2020. tab, graf
Article in English | LILACS | ID: biblio-1148058


The physiological quality of seeds is influenced by the climatic factors of production fields. The identification of the best conditions of P. maximum cv. Mombasa production fields allows the improvement of the seed sector. The aim of this work was to identify which climatic conditions of production fields can affect the physiological quality of P. maximum cv. Mombasa seeds. Nineteen plots from states of São Paulo (six from municipalities of Auriflama and three from Guzolândia) and Goiás (eight from Quirinópolis and two from Serranópolis), were collected by soil sweeping. The following parameters were evaluated: water content, germination rate, first germination count and germination rate index, seedling emergence in sand and field. Completely randomized design was used for all variables, with the exception of seedling emergence in field, since this variable required block design. Means were compared by the Scott-Knott test, at 5% probability. For the identification of the influence of climatic conditions on the physiological quality of seeds, multivariate statistical analysis was applied through Group and Principal Component Analysis. Production fields of Panicum maximum cv. Mombasa seeds presenting maximum temperatures above 32 ºC at flowering and natural fall stages produce seeds of low physiological quality. Production fields in which precipitation and high temperatures occur during natural fall and harvest of P. maximum cv. Mombasa seeds are not favorable to the production of seeds with high physiological quality.

A qualidade fisiológica das sementes é influenciada pelos fatores climáticas doscampos de produção. A identificação das condições dos melhores campos de produção de P. maximum cv. Mombaça permite aprimoramento do setor de sementes. O objetivo desse trabalho foi identificar quais condições climáticas dos campos de produção podem afetar a qualidade fisiológica das sementes de P. maximum cv. Mombaça. Foram avaliados dezenove lotes procedentes do estado de São Paulo (seis de Auriflama e três de Guzolândia) e Goiás (oito de Quirinópolis e dois de Serranópolis), colhidos por varredura do solo. Foram avaliados por meio dos seguintes parâmetros: teor de água, germinação, primeira contagem de germinação e índice de velocidade de germinação, emergência de plântulas em areia e em campo. Adotou-se delineamento inteiramente casualizado para todas as variáveis, com exceção da emergência de plântulas em campo, pois neste adotou-se delineamento em blocos. As médias foram comparadas pelo teste Scott-Knott, a 5% de probabilidade. Para a identificação da influência das condições climáticas na qualidade fisiológica das sementes aplicou-se análise estatística multivariada por meio de Análise de Agrupamento e Componentes Principais. Campos de produção de sementes de Panicum maximum cv. Mombaça que apresentam temperaturas máximas superiores a 32 ºC nas épocasde florescimento e degrana produzem sementes de baixa qualidade fisiológica. Campos de produção em que ocorram precipitações e altas temperaturas durante a degrana e à colheita de sementes de P.maximum cv. Mombaça não são favoráveis a produção de sementes com alta qualidade fisiológica.

Seeds , Multivariate Analysis , Brachiaria , Panicum
Electron. j. biotechnol ; 48: 86-94, nov. 2020. tab, graf, ilus
Article in English | LILACS | ID: biblio-1254836


BACKGROUND: Chinese hamster ovary (CHO) cells are the workhorse for obtaining recombinant proteins. Proteomic studies of these cells intend to understand cell biology and obtain more productive and robust cell lines for therapeutic protein production in the pharmaceutical industry. Because of the great importance of precipitation methods for the processing of samples in proteomics, the acetone, methanol-chloroform (M/C), and trichloroacetic acid (TCA)-acetone protocols were compared for CHO cells in terms of protein recovery, band pattern resolution, and presence on SDS-PAGE. RESULTS: Higher recovery and similar band profile with cellular homogenates were obtained using acetone precipitation with ultrasonic bath cycles (104.18 ± 2.67%) or NaOH addition (103.12 ± 5.74%), compared to the other two protocols tested. TCA-acetone precipitates were difficult to solubilize, which negatively influenced recovery percentage (77.91 ± 8.79%) and band presence. M/C with ultrasonic homogenization showed an intermediate recovery between the other two protocols (94.22 ± 4.86%) without affecting protein pattern on SDS-PAGE. These precipitation methods affected the recovery of low MW proteins (< 15 kDa). CONCLUSIONS: These results help in the processing of samples of CHO cells for their proteomic study by means of an easily accessible, fast protocol, with an almost complete recovery of cellular proteins and the capture of the original complexity of the cellular composition. Acetone protocol could be incorporated to sample-preparation workflows in a straightforward manner and can probably be applied to other mammalian cell lines as well.

Animals , Recombinant Proteins , CHO Cells , Proteomics/methods , Acetone , Chemical Precipitation , Solubility , Trichloroacetic Acid , Cell Separation , Chloroform , Cell Culture Techniques , Methanol , Electrophoresis, Polyacrylamide Gel
Int J Pharm Pharm Sci ; 2020 May; 12(5): 41-46
Article | IMSEAR | ID: sea-206092


Objective: The study aims to investigate the antifungal response of the dug usnic acid with the carrier graphene. Methods: Nano-precipitation method by sonication was adopted to formulate the conjugate. SEM test was performed to check the shape and average size of the conjugate. FTIR test was performed for the chemical interaction between the drug and the carrier. Ointment was prepared by the fusion method and the viscosity test was performed by Brookfield viscometer. Spreadability test was performed by slide method. Animal activity was performed to confirm the antifungal effect of the formulated nano-conjugate. Statistical analysis was done by Anova. Results: SEM study shows that the conjugate is in the nano range and possess a spherical shape. FTIR study shows no interaction between the drug and the carrier. The result of in vitro drug release study shows that the conjugate posses a higher drug release rate as compared to the drug alone. Topical drug administration is more suitable for the treatment of the fungal infection, so the nano-conjugate was incorporated into the ointment by geometric mixing. The viscosity and the spreadability test were performed on the different formulations of the ointment and the suitable one was selected for the topical administration. Anti-fungal study had been performed on the Wistar albino rats for 6 d. Skin culture of rats was performed for the formation of the fungal colonies. Statistical analysis by Anova gives p<0.001. It was found that the normal form of usnic acid, graphene and the nano form both possess anti-fungal activity as 3/6 and 2/6 experimental animals are cured by normal formulation and nano-formulation. Conclusion: The present anti-fungal study revealed that the nano-form of the conjugate possess higher anti-fungal activity than the normal formulation of usnic acid with graphene.

Article | IMSEAR | ID: sea-210729


Vanillic acid (4-hydroxy-3-methoxybenzoic acid) is a phenolic acid found in many plant extracts. It is used as aflavoring and scent agent and produces a pleasant, creamy odor. It is widely used in many applications for therapeuticpurposes to flavoring agent. Molecularly imprinted polymers of vanillic acid were synthesized by precipitationpolymerization with a noncovalent approach for the extraction from blood serum. Three different imprinted polymershave been synthesized with varying molar ratio of monomer. The synthesized polymer particles were characterizedusing Fourier-transform infrared spectroscopy and scanning electron microscopy. The extraction efficiency of highlyselected imprinted polymer of vanillic acid from spiked blood serum was about 80%.

Arq. Asma, Alerg. Imunol ; 4(1): 121-128, jan.mar.2020. ilus
Article in English | LILACS | ID: biblio-1381795


Introduction: Allergen proteins found in dust mite extracts, such as Dermatophagoides farinae (DF), Dermatophagoides pteronyssinus (DP) and Tyrophagus putrescentiae (TP), are relevant for scientific studies in the allergy and immunotherapy fields. The precipitation/concentration of protein extracts may favor the aggregation of the allergens in homogenates. Objective and method: This paper investigates the precipitation process by submitting crude mite extracts to compounds such as ammonium sulfate (NH4)2SO4, trichloroacetic acid (TCA) and acetone. Results: The best results were obtained by fractionation with (NH4)2SO4 at 80% (w/v) saturation (~0° C), observing the protein markings on the electrophoresis gel. Major allergens were identified by immunoblot at 25 kDa (cysteine protease) for Der f and Der p; and 25 kDa, 30 kDa (tropomyosin) and Try p 3, near 26 kDa. For this percentage the total protein contents were 12.83 mg mL-1 for Der f, 24.78 mg mL-1 for Der p and 27.35 mg mL-1 for Try. Conclusion: An advantage of precipitation with (NH4)2SO4 over precipitation with acetone was the possibility of gradually obtaining protein fractions, which does not happen when using the latter. The addition of 80% (v/v) acetone to the mite extracts favored total protein precipitation in the concentrations 16.42 mg mL-1, 28.47 mg mL-1 and 13.41 mg mL-1. The use of TCA in concentrations above 20% (w/v) forms peptides that are not retained in the gel under the established experimental conditions, and dilute solutions of this acid are more efficient.

Introdução: As proteínas alergênicas presentes nos extratos dos ácaros de poeira, tais como Dermatofagoides farinae (DF), Dermatofagoides pteronyssinus (DP) e Tyrophagus putrescentiae (TP) são relevantes para estudos científicos na área de alergias e aplicação em imunoterapias. A precipitação/concentração desses extratos proteicos pode favorecer a agregação de alérgenos nos homogenatos. Objetivo e método: O trabalho investiga o processo de precipitação, submetendo os extratos brutos de ácaros de poeira a compostos como sulfato de amônio (NH4)2SO4, ácido tricloroacético (ATC) e acetona. Resultados: Os melhores resultados foram obtidos por fracionamento com (NH4)2SO4 em 80% (m/v) de saturação (~ 0°C), observando as marcações proteicas no gel de eletroforese. Os alérgenos principais foram identificados por immunoblot em 25 kDa (cisteína protease) para Der f 1 e Der p 1; e 25 kDa, 33 kDa (tropomyosin), 11 kDa para Tyr. Para esse percentual, os teores de proteína total foram de 12.83 mg mL-1 para DF; 24,78 mg mL-1 para DP; e 27,35 mg mL-1 para TP. Conclusão: A vantagem da precipitação com (NH4)2SO4 frente à precipitação com acetona foi a possibilidade de gradativamente se obter frações proteicas, o que não acontece quando utilizado esse solvente. A adição de 80% (v/v) de acetona aos extratos de ácaros favoreceu a precipitação total de proteína nas concentrações 16,42 mg mL-1; 28,47 mg mL-1; e 13,41 mg mL-1. O uso de ATC em concentrações acima de 20% (m/v) forma peptídeos que não são retidos no gel nas condições experimentais estabelecidas, sendo eficiente soluções mais diluídas desse ácido.

Humans , Tropomyosin , Dermatophagoides farinae , Dermatophagoides pteronyssinus , Cysteine Proteases , Ammonium Sulfate , Mites , Acetone , Peptide Hydrolases , Solvents , Acids , Allergens , Proteins , Dust , Hypersensitivity
Article in English | WPRIM | ID: wpr-785393


Methods for reproducibly isolating and enriching small extracellular vesicles (EVs) from blood are essential for clinical utilization of small EVs in cancer patients. We combined ultracentrifugation (UC) with polymer-based precipitation (ExoQuick [EQ] or Total Exosome Isolation [TEI] kit) to isolate small EVs (diameter, 30–150 nm) from the serum of breast cancer patients. We compared the performance of four cycles of UC (UC4x) with that of two cycles of UC followed by enrichment using the EQ (UC2x→EQ) or TEI (UC2x→TEI) kits. The mean concentration of small EVs isolated from 1 mL of serum using UC2x→EQ (139.0±29.1 µg) and UC2x→TEI (140.4±5.0 µg) did not differ from that obtained using UC4x (141.8±26.9 µg). The mean number of EV particles obtained using UC4x was 29.2±9.9×109 per mL of serum, whereas UC2x→EQ and UC2x→TEI yielded higher numbers of EVs (50.7±17.0×10⁹ and 59.3±20.6×10⁹, respectively). Concentrations of EV microRNAs, including miR-21 and miR-155, did not differ between the three methods. In conclusion, performing UC prior to the use of polymer-based precipitation kits could be feasible for isolating small EVs from human serum in large sample-based translational researches.

Breast Neoplasms , Extracellular Vesicles , Humans , MicroRNAs , Translational Research, Biomedical , Ultracentrifugation
Acta Pharmaceutica Sinica ; (12): 45-53, 2020.
Article in Chinese | WPRIM | ID: wpr-780559


Plant polyphenols have a wide range of pharmacological activities and application prospects. Liquid polyphenol preparations have special physical phases and complex chemical compositions, with problems such as poor stability and easy precipitation during production and marketing. Taking the multi-precipitation mechanism of plant polyphenol liquid preparations as an example,we discuss the chemistry and composition of the precipitation, how it forms, whether precipitationcan be controlled, and the interaction law of three precipitation approaches. An unstable mechanism model is proposed where hydrolyzed tannin hydrolysis and catechin non-enzymatic oxidative polymerization repeatedly induces associative colloid aggregation and precipitation. This study explains the complex physicochemical changes in polyphenol solutions and the microcosmic mechanism of instability in the induced system and proposes a steady state reconstruction of liquid polyphenol preparation consistent with the common law of precipitation and control. It has scientific significance for promoting the development and manufacture of high quality liquid polyphenol preparations.