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1.
Biomédica (Bogotá) ; 41(3): 555-589, jul.-set. 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1345403

ABSTRACT

Resumen En la última década se ha incrementado el número de estudios y publicaciones sobre las vesículas extracelulares y los exosomas. En Colombia, ha habido interés y avances en su estudio, lo que se evidencia en el aumento de publicaciones y proyectos de investigación. Sin embargo, este es un campo de investigación aún en desarrollo, con desafíos analíticos y limitaciones técnicas, por lo cual, en el planteamiento de los proyectos de investigación y desarrollo, es necesario considerar cuál es el estado del campo científico a nivel mundial en cuanto a la nomenclatura y la clasificación de las vesículas extracelulares, las técnicas, recursos, requisitos y especificaciones de calidad y las instituciones que regulan el campo. La respuesta a esta pregunta permitirá desarrollar estudios que cumplan con los estándares internacionales, y las exigencias y recomendaciones institucionales. Sin embargo, la información científica disponible se encuentra dispersa y no todos los aspectos son tratados a cabalidad. En este actualización se condensa la información disponible y se presentan los términos oficiales para denominar las vesículas extracelulares y la nomenclatura aceptada actualmente, así como la evolución del campo, la homogenización de los parámetros experimentales, el establecimiento de autoridades científicas, instituciones y recursos, y las recomendaciones que se han generado a nivel mundial para el desarrollo de investigaciones en vesículas extracelulares, incluidos su aislamiento, caracterización y estudio funcional. Por último, se analiza el contexto nacional de una forma crítica, teniendo en cuenta las fortalezas institucionales, los errores usualmente cometidos, y las técnicas y tecnologías analíticas disponibles.


Abstract In the last decade, the number of studies and publications on extracellular vesicles (EV) and exosomes has boomed. Colombia has displayed interest and progress in their study as shown in the increase of research project publications and products. However, this research field is still developing and has its own analytical challenges and technical limitations. For planning research projects and developing EV studies it is necessary to consider what is the state of the scientific field worldwide concerning EV nomenclature and classification, available techniques, resources, requirements and quality specifications, and the institutions that regulate the field. Answering this question will elicit EV studies that comply with international standards and respond to institutional demands and recommendations. However, the scientific information available is scattered and not all the aspects are considered in full. In this update, the available information is condensed and the official terms and currently defined nomenclature is presented, as well as the evolution of the field, the homogenization of the experimental parameters, the establishment of scientific authorities, institutions, and resources, and the recommendations generated worldwide for their development and research including their isolation, characterization, and functional studies. Finally, I analyzed the national context in a critical way, considering institutional strengths, common mistakes, and available analytical techniques and technologies.


Subject(s)
Extracellular Vesicles , Chemistry Techniques, Analytical , Resource Guide , Cell-Derived Microparticles , Exosomes , Chemical Phenomena , Terminology as Topic
2.
Salud bienestar colect ; 4(3): 39-57, sept.-dic. 2020. tab
Article in Spanish | LILACS | ID: biblio-1281954

ABSTRACT

Con el propósito de caracterizar la praxis Bioanalítica desde la matriz epistemológica vigente, la investigación se realizó bajo el Enfoque Integrador Transcomplejo. Para el abordaje de la problemática de estudio se empleó la complementariedad metódica. El grupo humano quedó constituido por cinco docentes Bioanalistas, a los que se le realizó una entrevista focalizada y en profundidad. Entre los hallazgos se evidenció que la praxis bioanalítica fue modelada desde la modernidad como un ejercicio mecanicista, repetitivo, desarticulado de lo social y lo humano. La modernidad es reproducida en las universidades mediante una formación vertical, donde no se articula lo biológico con lo social, con lo histórico o lo cultural; ya que la malla curricular está definida por un grupo de asignaturas cargados de contenidos procedimentales, impartidos a partir de objetivos de forma aislada, que centra la atención en la enfermedad y concibe su praxis desde roles y tareas, dándole mayor énfasis al rol de analista. Desde esta perspectiva, se niega los aportes dados por la epistemología, la historia, lo sociología, antropología y la educación al saber Bioanalítico, quedando limitado su impacto en la Salud Pública. Para redimensionar la concepción social del Bioanálisis y su praxis es necesario que se asuman nuevos paradigmas y nuevas metodologías y la Transcomplejidad constituye una opción para dar respuesta a esta demanda.


In purpose to characterize the Bioanalytical praxis from the current epistemological matrix, the research was carried out under the TranscomplexIntegrative Approach. Methodical complementarity was used to address the study problem. The human group was made up of five Bioanalyst teachers, who were given a focused and in-depth interview. Among the findings, it was evident that bioanalytic praxis was modeled since modernity as a mechanistic, repetitive, disjointed exercise of the social and the human. Modernity is reproduced in universities through vertical training, where the biological is not articulated with the social, with the historical or the cultural; since the curricular mesh is defined by a group of subjects loaded with procedural content, taught from objectives in isolation, which focuses attention on the disease and conceives its praxis from roles and tasks, giving greater emphasis to the role of analyst. From this perspective, the contributions given by epistemology, history, sociology, anthropology and education to Bioanalytical knowledge are denied, leaving their impact on Public Health limited. To resize the social conception of Bioanalysis and its praxis, it is necessary to assume new paradigms and new methodologies and Transcomplexity constitutes an option to respond to this demand.


Subject(s)
Humans , Biological Assay , Chemistry Techniques, Analytical , Public Health , Social Values , Venezuela , Interview , Biomedical Research/methods , Professional Training
3.
Chinese Journal of Biotechnology ; (12): 1261-1268, 2020.
Article in Chinese | WPRIM | ID: wpr-826851

ABSTRACT

The phenomenon of phase separation of intracellular biological macromolecules is an emerging research field that has received great attention in recent years. As an aggregation and compartment mechanism of cell biochemical reactions, it widely exists in nature and participates in important physiological processes such as gene transcription and regulation, as well as influences organism's response to external stimuli. Disequilibrium of phase separation may lead to the occurrence of some major diseases. Researchers in cross-cutting fields are trying to examine dementia and other related diseases from a new perspective of phase separation, exploring its molecular mechanism and the potential possibility of intervention and treatment. This review intends to introduce the latest research progress in this field, summarize the major research directions, biochemical basis, its relationship with disease occurrence, and giving a future perspective of key problems to focus on.


Subject(s)
Animals , Chemistry Techniques, Analytical , Cytoplasm , Chemistry , Metabolism , Humans , Macromolecular Substances , Research
4.
Chinese Journal of Biotechnology ; (12): 2181-2192, 2020.
Article in Chinese | WPRIM | ID: wpr-878477

ABSTRACT

Biological desulfurization is a process in which sulfur compounds are removed from gas and oil using microorganisms. It is a simple process that has mild operating conditions, high desulfurization efficiency, low energy consumption and less environmental pollution. However, there is still a lack of simple and efficient analytical methods for quantitatively analyzing the sulfur compounds in the biological desulfurization process. In order to solve this problem, the analytical method for the simultaneous determination of sulfite, thiosulfate and sulfide in biological desulfurization solutions by pre-column fluorescence derivation using high performance liquid chromatography (HPLC) was developed. The standard curves of sulfur species in this analytical method had good linear relationships with correlation coefficients of 0.999 5, 0.999 7, and 0.999 7 for sulfite, thiosulfate and sulfide, respectively. The detection limits of these sulfur compounds were 0.000 6, 0.000 7 and 0.001 1 μmol/L; the range of recovery rates were 98.17 to 101.9%, 100.9 to 102.6%, and 101.1 to 104.2%; which had good repeatability and stability. The analytical method was simple, efficient and accurate, and could be used to simultaneously determine the sulfur compounds in different biological desulfurization systems.


Subject(s)
Chemistry Techniques, Analytical/methods , Chromatography, High Pressure Liquid , Sulfur Compounds/analysis
5.
Article in English | WPRIM | ID: wpr-776898

ABSTRACT

Two new isomeric modified tripeptides, aspergillamides C and D (compounds 1 and 2), together with fifteen known compounds (compounds 3-17), were obtained from the marine sponge-derived fungus Aspergillus terreus SCSIO 41008. The structures of the new compounds, including absolute configurations, were determined by extensive analyses of spectroscopic data (NMR, MS, UV, and IR) and comparisons between the calculated and experimental electronic circular dichroism (ECD) spectra. Butyrolactone I (compound 11) exhibited strong inhibitory effects against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with the IC being 5.11 ± 0.53 μmol·L, and acted as a noncompetitive inhibitor based on kinetic analysis.


Subject(s)
4-Butyrolactone , Chemistry , Pharmacology , Animals , Aspergillus , Chemistry , Chemistry Techniques, Analytical , Dipeptides , Chemistry , Pharmacology , Enzyme Inhibitors , Chemistry , Pharmacology , Indoles , Chemistry , Pharmacology , Molecular Structure , Mycobacterium tuberculosis , Peptides , Chemistry , Pharmacology , Polyketides , Chemistry , Pharmacology , Porifera , Microbiology , Protein Tyrosine Phosphatases , Chemistry
6.
Article in English | WPRIM | ID: wpr-776897

ABSTRACT

Romipeptides A and B (1 and 2), two new romidepsin derivatives, and three known compounds, chromopeptide A (3), romidepsin (4) and valine-leucine dipeptide (5) were isolated from the fermentation broth of Chromobacterium violaceum No. 968. Their structures were elucidated by interpretation of their UV, HR-ESI-MS and NMR spectra. The absolute configuration of compound 1 and 2 were established by single crystal X-ray diffraction analysis. Compounds 1-5 were evaluated for their anti-proliferative activities against three human cancer cell lines, SW620, HL60, and A549. The results showed most of these compounds exhibited antitumor activities in vitro, in which compound 2 displayed potent cytotoxicity to SW620, HL60 and A549 cell lines, with IC of 12.5, 6.7 and 5.7 nmol·L, respectively.


Subject(s)
Antineoplastic Agents , Chemistry , Pharmacology , Cell Line, Tumor , Cell Proliferation , Cell Survival , Chemistry Techniques, Analytical , Chromobacterium , Metabolism , Depsipeptides , Chemistry , Pharmacology , Dipeptides , Chemistry , Drug Screening Assays, Antitumor , Fermentation , Humans , Molecular Structure , Peptides, Cyclic , Chemistry
7.
Article in English | WPRIM | ID: wpr-773638

ABSTRACT

Two cyclopeptides, celogentin L (1) and its epimer lyciumin A (2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1D-, 2D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2D-NMR and comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma HepG2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.


Subject(s)
A549 Cells , Cell Survival , Celosia , Chemistry , Chemistry Techniques, Analytical , HeLa Cells , Hep G2 Cells , Humans , Molecular Conformation , Molecular Structure , Peptides, Cyclic , Chemistry , Toxicity , Seeds , Chemistry , Stereoisomerism
8.
Article in Chinese | WPRIM | ID: wpr-772597

ABSTRACT

OBJECTIVE@#: To analyze experimental factors affecting recovery of puerarin in microdialysis.@*METHODS@#: Puerarin concentration in microdialysate samples was determined by high performance liquid chromatography. The methods of direct dialysis, retrodialysis and the zero-net flux were used to calculate recovery, respectively. The effects of perfusate composition, the analyte concentration, perfusate flow rate, medium temperature and stir rates of the dialysis medium on recovery were investigated.@*RESULTS@#: There were significant differences in the recovery values among direct dialysis, retrodialysis and zero-net flux methods. The recovery for 0.9% NaCl solution, Ringer's solution, PBS and anticoagulant dextrose solution as perfusate fluid were (71.25±2.36)%,(73.48±1.41)%,(68.50±2.43)% and (74.98±1.16)%, respectively. The composition of perfusate fluid had significant influence on the recovery(<0.01). At the same flow rate, recovery was independent of the analyte concentration. At the same concentration, the recovery was decrease with the increasing flow rate in an exponential relationship. The recovery increased with the raising temperature and stir rate of the dialysis medium, and the recovery remained stable when the stir rate reached above 200 rpm.@*CONCLUSIONS@#: A study method for recovery of puerarin in microdialysis has been established, and the recovery of puerarin is affected by calculating methods, perfusate fluids, flow rate, medium temperature and stir rate, but not affected by analyte concentrations.


Subject(s)
Chemistry Techniques, Analytical , Methods , Chromatography, High Pressure Liquid , Isoflavones , Microdialysis
9.
Article in English | WPRIM | ID: wpr-812428

ABSTRACT

Two cyclopeptides, celogentin L (1) and its epimer lyciumin A (2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1D-, 2D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2D-NMR and comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma HepG2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.


Subject(s)
A549 Cells , Cell Survival , Celosia , Chemistry , Chemistry Techniques, Analytical , HeLa Cells , Hep G2 Cells , Humans , Molecular Conformation , Molecular Structure , Peptides, Cyclic , Chemistry , Toxicity , Seeds , Chemistry , Stereoisomerism
10.
Rev. fac. cienc. méd. (Impr.) ; 14(2): 36-40, jun.-dic. 2017. ilus
Article in Spanish | LILACS | ID: biblio-882654

ABSTRACT

El seno preauricular es una malformación congénita que se presenta como un pequeño orificio en el oído externo, usualmente cercano al borde anterior de la rama ascendente del hélix. La mayoría son asintomáticos y no requieren tratamiento, sin embargo, una vez infectados se vuelven inflamaciones dolorosas, con secreción fétida que presentan exacerbaciones agudas recurrentes. Objetivo: brindar información actualizada sobre las ventajas de las diferentes técnicas quirúrgicas utilizadas para resolver en forma adecuada este problema congénito. Material y Métodos : el presente estudio se realizó mediante una búsqueda comprensiva de artículos con menos de 10 años de publicación en las bases de datos de MEDLINE/PubMed, Google Académico e HINARI. Se seleccionaron un total de 20 artículos, en español e inglés, entre ellos trabajos originales y metanálisis sobre el tema. Conclusión : la técnica suprauricular ha demostrado, en términos estadísticos, una tasa de recurrencia menor que la técnica clásica de sinectomía...(AU)


Subject(s)
Humans , Chemistry Techniques, Analytical/methods , Congenital Abnormalities/diagnosis , Ear Deformities, Acquired/genetics , Earache/complications , Review
11.
ImplantNewsPerio ; 2(6): 1050-1059, nov.-dez. 2017. ilus, tab
Article in Portuguese | LILACS, BBO | ID: biblio-880834

ABSTRACT

Objetivo: analisar a composição química da superfície de três implantes antes e depois de manter contato com pinça de titânio, e verificar se níveis importantes de elementos químicos contaminantes foram adsorvidos aos implantes. Material e métodos: através de MEV (microscópio eletrônico de varredura) e EDS (espectrometria de energia dispersiva), as superfícies dos implantes foram caracterizadas quimicamente antes e após o contato com pinça de titânio utilizada rotineiramente em uma clínica odontológica. Resultados: houve presença de titânio com 99,51% de média nas superfícies antes do contato com pinça de titânio, e 99,43% de média de titânio após o contato com pinça de titânio. Elementos como ferro, silício, cloro e alumínio foram encontrados em concentrações menores do que 0,55%, tanto antes quanto depois da manipulação com a pinça. Conclusão: não houve contaminação química detectável pela metodologia empregada neste estudo da superfície dos implantes após o contato com a pinça de titânio, porém, uma amostra mais significativa e o emprego de critérios que possam definir com mais precisão as áreas de análise parecem ser necessários para resultados ainda mais consistentes.


Objective: to analyze the chemical composition surface of three implants before and after titanium tweezers contact and check whether important levels of contaminants chemical elements were adsorbed to the implants. Material and methods: through SEM (scanning electron microscope) and EDS (energy dispersive spectroscopy) the implants surfaces were characterized chemically before and after contact with titanium tweezers frequently used in dental clinic. Results: the surfaces before contact with the titanium tweezers showed the presence of titanium 99.51% average and 99.43% average of titanium after contact with the titanium clamp. Elements such as iron, silicon, chlorine and aluminum have been found in lower concentrations than 0.55%, both before and after handling with forceps. Conclusion: therefore, no chemical contamination was detected by the method used in this study of the implant surface after contact with titanium tweezers, however, a more signifi cant sample and the use of criteria that can defi ne more precisely the areas of analysis, appear to be required for further consistent results.


Subject(s)
Humans , Male , Female , Chemical Phenomena/methods , Chemistry Techniques, Analytical , Environmental Pollution/analysis , Dental Implantation , Titanium/analysis
12.
ImplantNewsPerio ; 2(4): 629-636, jul.-ago. 2017. ilus
Article in Portuguese | LILACS, BBO | ID: biblio-859996

ABSTRACT

Os trabalhos disponíveis na literatura apresentam resultados divergentes da análise da composição química da superfície dos implantes comerciais, por empregarem diferentes técnicas. Considerando que esta propriedade influencia na osseointegração, os cirurgiões-dentistas precisam ter confiança nas informações obtidas na literatura e nas fornecidas pelos fabricantes. Quando a análise da superfície é feita de modo correto, é possível identificar diferenças positivas e negativas na composição química entre os implantes comerciais. O objetivo do presente trabalho foi apresentar resultados das análises da composição química da superfície de implantes comerciais produzidos no Brasil e importados, e sugerir procedimentos para estas análises. Os resultados mostraram que os implantes jateados são os que possuem maior probabilidade de terem contaminantes na superfície, e a análise da composição química usando EDS (energy dispersive x-ray spectroscopy) é a técnica que apresenta menor confiabilidade.


Published papers have shown divergent results regarding the chemical composition of commercially available dental implant surfaces due to different analytical techniques. Considering that this can infl uence the osseointegration process, dental practitioners need to be confi dent on literature and fabricant information. When surface analysis is correctly employed, it is possible to identify positive and negative aspects on several chemical characteristics. The aim of this paper is to present the outcomes of national and international dental implant surfaces and to suggest procedures accordingly. It was demonstrated that sandblasted surfaces are more prone to have contaminants, and that energy dispersive X-ray spectroscopy (EDS) is the technique presenting low reliability levels.


Subject(s)
Chemical Phenomena/methods , Chemistry Techniques, Analytical , Environmental Pollution/analysis , Dental Implants
13.
Acta bioquím. clín. latinoam ; 51(2): 227-235, jun. 2017. graf, tab
Article in Spanish | LILACS | ID: biblio-886116

ABSTRACT

El objetivo del trabajo fue evaluar el desempeño anual de los métodos, en términos de error total (ET), las distintas especificaciones de calidad disponibles y el modelo Seis Sigma para calificar desempeño. Se evaluaron analitos con variabilidad biológica (VB), muy baja, baja, media y alta. Se calculó el ET (ETc) y el sigma (s) mensual a dos niveles de control; el ET permitido (ETp) para cada analito se obtuvo de 8 fuentes (metas biológicas y regulatorias). Se consideró desempeño aceptable cuando ETc

The aim of this work was to evaluate the annual performance of the methods in terms of total error (TE), the different quality specifications available, and the Six Sigma model to qualify performance. Analytes with very low, low, medium and high biological variability (BV) were evaluated. TE (TEc) and sigma (s) were calculated monthly at two levels of control; allowable TE (TEa) for each analyte was obtained from 8 sources (biological and regulatory goals). Acceptable performance was considered when TEc

O objetivo do trabalho foi avaliar o desempenho anual dos métodos em termos de erro total (ET), as diferentes especificações de qualidade disponíveis e o modelo Seis Sigma para qualificar desempenho. Foram avaliados analitos com variabilidade biológica (VB) muito baixa, baixa, média e alta. Calculou-se ET (ETc) e o sigma (s) mensal a dois níveis de controle; o ET permitido (ETp) para cada analito foi obtido de 8 fontes (metas biológicas e regulatórias). Levou-se em consideração o desempenho aceitável quando ETc < ETp e s≥3. Foi observada a estabilidade analítica durante o período de avaliação. Não foram alcançadas as metas biológicas para analitos com VB muito baixa, algo semelhante aconteceu para analitos com VB baixa e média; com VB alta alcançaram todas as especificações. O desempenho s e a regra de controle de Westgard dependeram do ETp escolhido; para magnésio, com CLIA (ETp=25%) se obteve s >10 (World Class) e simples regra (13s), com VB mínima s <3 e multirregra. Conclui-se que a aceitação do desemperno do método e as regras de controle dependeram do ETp escolhido, sem disporem nesse meio de metas mínimas a alcançar. O monitoramento mensal do ETc mostrou a estabilidade analítica com variabilidade típica de cada método.


Subject(s)
Quality Control , Analytical Quality Control/methods , Chemistry Techniques, Analytical/standards , Total Quality Management , Clinical Laboratory Techniques
14.
An. acad. bras. ciênc ; 89(2): 1295-1303, Apr.-June 2017. tab
Article in English | LILACS | ID: biblio-886692

ABSTRACT

ABSTRACT The objective of this study was to compare the estimates of ether extract (EE) contents obtained by the Randall method and by the high-temperature method of the American Oil Chemist's Society (AOCS; Am 5-04) in forages (n = 20) and cattle feces (n = 15). The EE contents were quantified by using the Randall extraction or AOCS method and XT4 filter bags or cartridges made of qualitative filter paper (80 g/m²) as containers for the samples. It was also evaluated the loss of particles, and concentration of residual chlorophyll after extraction and the recovery of protein and minerals in the material subjected to extraction. Significant interaction was observed between extraction method and material for EE contents. The EE estimates using the AOCS method were higher, mainly in forages. No loss of particles was observed with different containers. The chlorophyll contents in the residues of cattle feces were not affected by the extraction method; however, residual chlorophyll was lower using the AOCS method in forages. There was complete recovery of the protein and ash after extraction. The results suggest that AOCS method produces higher estimates of EE contents in forages and cattle feces, possibly by providing greater extraction of non-fatty EE.


Subject(s)
Animals , Chemistry Techniques, Analytical/methods , Ether/analysis , Ether/chemistry , Feces/chemistry , Poaceae/chemistry , Animal Feed/analysis , Cattle , Reproducibility of Results , Food Analysis/methods , Hot Temperature
15.
Article in English | WPRIM | ID: wpr-812110

ABSTRACT

The present study was designed to establish a multi-wavelength quantitative fingerprinting method for San-Huang Tablets (SHT), a widely used and commercially available herbal preparation, where high performance liquid chromatography (HPLC) with a diode array detector (DAD) was employed to obtain the fingerprint profiles. A simple linear quantitative fingerprint method (SLQFM) coupled with multi-ingredient simultaneous determination was developed to evaluate the quality consistency of the tested samples qualitatively and quantitatively. Additionally, the component-activity relationship between chromatographic fingerprints and total radical-scavenging capacity in vitro (as assessed using the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay) was investigated by partial least squares regression (PLSR) analysis to predict the antioxidant capacity of new samples from the chromatographic fingerprints and identify the main active constituents that can be used as the target markers for the quality control of SHT. In conclusion, the strategy developed in the present study was effective and reliable, which can be employed for holistic evaluation and accurate discrimination for the quality consistency of SHT preparations and other traditional Chinese medicine (TCM) and herbal preparations as well.


Subject(s)
Antioxidants , Chemistry , Biphenyl Compounds , Chemistry , Chemistry Techniques, Analytical , Methods , Chromatography, High Pressure Liquid , Methods , Drugs, Chinese Herbal , Chemistry , Free Radicals , Chemistry , Molecular Structure , Picrates , Chemistry , Quality Control , Tablets , Chemistry
16.
Article in Chinese | WPRIM | ID: wpr-283017

ABSTRACT

<p><b>OBJECTIVE</b>To compare the determination methods of fiber number concentration between China and WHO.</p><p><b>METHODS</b>Individual fiber samplings were conducted at a RCF manufacturing enterprise for 40 types of work. Flow rate was set as 2 L/min and lasted 2 to 4 hours. We used acetone-triacetin to prepare samples. The rules of two methods were used to count fibers for each sample respectively. The differences between the results of two methods were compared using the sign-rank test, and the correlation between the two methods' counting results were evaluated by the Spearsman rank correlation analysis.</p><p><b>RESULTS</b>The results of WHO counting rule were higher than those of Chinese counting rule for the same sample. The ratios of WHO method to Chinese method ranged from 1.88 to 3.70. Paired sign-rank test found the statistically significant differences of the results between the two methods (P<0.01). The rank correlation coefficient of the results by two rules counting ranged between 0.621 to 0.975, suggested positive correlation (P<0.01). The possible reasons of the difference between the two methods included the difference between the shapes of asbestos fiber and man-made mineral fiber, and counting rules of two methods.</p><p><b>CONCLUSION</b>The results of WHO counting method is higher than those of Chinese counting method. High correlations between the results of the two methods were observed.</p>


Subject(s)
Asbestos , Chemistry Techniques, Analytical , Methods , China , Humans , Mineral Fibers , Specimen Handling , World Health Organization
17.
Article in Chinese | WPRIM | ID: wpr-337940

ABSTRACT

High resolution melting (HRM), an important technology for genotyping and mutation scanning, has broad prospects in the authentification of traditional Chinese medicine. This paper selected universal trnH-psbA primers and used HRM to establish a new methods for identification of Akebia herbs. PCR was conduct at the annealing temperature of 58 degrees C and 35 cycles. The range of the DNA template concentration, the primer concentration and the Mg2+ ion concentration were further analyzed. The results showed the Tm values of Caulis Akebiae was (81.84 ± 0.16), (85.28 ± 0.16) degrees C and Caulis Clematidis Armandii was (83.22 ± 0.19) degrees C and Caulis Aristolochiae manshuriensis was (81.67 ± 0.14) degrees C, (84.24 ± 0.10) degrees C with 5-125 mg - L-' DNA template, 0.4 μmol x L(-1) primer, 2.0 mmol x L(-1) Mg2+. This method can achieve the authentification of Akebia herbs and is simple, fast, high-throughput, visual.


Subject(s)
Chemistry Techniques, Analytical , Methods , DNA, Plant , Chemistry , Genetics , Genotype , Magnoliopsida , Chemistry , Classification , Genetics , Phylogeny , Transition Temperature
18.
Bol. latinoam. Caribe plantas med. aromát ; 13(4): 344-350, jul. 2014. ilus, tab
Article in English | LILACS | ID: lil-785452

ABSTRACT

Members of the family Cyperaceae such as Cyperus alopecuroides, Cyperus articulatus, Cyperus scariosus and Cyperus rotundus possess significant amount of studies about their antioxidant activities and other properties. Nevertheless, the plant Cyperus digitatus belonging to the genus Cyperus lacks of studied about any kind of intrinsic activity. Different extracts and fractions were obtained from the rhizomes of Cyperus digitatus, and a Phytochemical screening and the content of phenols and flavonoids and the antioxidant properties (FRAP, DPPH and beta-Carotene bleaching) were quantified in each of theextracts and fractions. Of all the extracts obtained, the BE and AqE extracts showed the best antioxidant potential, meanwhile, none of the fractions obtained from the EAE extract show a relevant activity.


Los miembros de la familia Cyperaceae, tales como Cyperus alopecuroides, Cyperus articulatus, Cyperus scariosus y Cyperus rotundus poseen una cantidad significativa de estudios sobre sus actividades antioxidantes y otras propiedades. Sin embargo, la planta Cyperus digitatus perteneciente al género Cyperus carece de estudio de cualquier tipo de actividad intrínseca. Razón por la cual se estudió sus propiedades antioxidantes (FRAP, DPPH y blanqueamiento del beta-caroteno), cuantificación de contenido fenolico y flavonoides totales en extractos y fracciones obtenidos de los rizomas de Cyperus digitatus, y un perfil fitoquímico. De todos los extractos obtenidos, BE y AqE mostraron el mejor potencial antioxidante, por otra parte ninguna de las fracciones obtenidas a partir del extracto EAE mostro una actividad relevante.


Subject(s)
Antioxidants/pharmacology , Cyperus/chemistry , Plant Extracts/pharmacology , Rhizome/chemistry , Biphenyl Compounds , Plant Extracts/chemistry , Ferrous Compounds , Phenols/analysis , Flavonoids/analysis , Oxidation-Reduction , Oxidative Stress , Chemistry Techniques, Analytical/methods
19.
Acta bioquím. clín. latinoam ; 48(2): 183-189, jun. 2014. graf, tab
Article in Spanish | LILACS | ID: lil-734226

ABSTRACT

El laboratorio debe garantizar la exactitud de los resultados de HbA1c cumpliendo con los requisitos analíticos internacionales de calidad, cada vez más estrictos y asegurar que una variación de HbA1c de 0,5 puntos porcentuales (%-NGSP) o más entre dos controles consecutivos de un paciente diabético se deba a una variación clínica y no a una variación analítica. En este trabajo se evaluó el desempeño analítico de tres métodos comerciales para HbA1c: inmunoturbidimétrico, enzimático y cromatográfico de intercambio catiónico. Para tal fin, se procesaron por cada método distintos controles comerciales de HbA1c, con trazabilidad al método de referencia IFCC, determinándose en cada caso Coeficiente de Variación Total, Bias, Error Total, Valor de Referencia del Cambio y cambio clínico significativo de HbA1c en el punto crítico 7,0%-NGSP. En las condiciones analíticas de este trabajo, solamente el método inmunoturbidimétrico tuvo un desempeño analítico aceptable, permitiendo atribuir un cambio de 0,5%-NGSP a una variación clínica significativa del paciente. Frente a las recomendaciones internacionales sobre el uso de HbA1c en el control y diagnóstico de diabetes, es indiscutible la importancia de elegir un método que satisfaga los requerimientos analíticos mínimos de calidad para asegurar la utilidad clínica del resultado de HbA1c.


The laboratory must guarantee the accuracy of HbA1c results meeting the increasingly strict international analytical quality standards and assuring that an HbA1c variation of 0.5 percentage points (%-NGSP) or more between two consecutive controls of a diabetic patient is due to a clinical variation and not to an analytical variation. In this paper, the analytical performance of three commercial methods for HbA1c: Immunoturbidimetric, Chromatographic and Enzymatic Cation Exchange, were evaluated. For this purpose, commercial controls with assigned values traceable to the IFCC reference method for HbA1c were processed. For each methodology, total Coefficient of Variation (CV%), Bias%, Total Error (TE%), Change Reference Value and Clinically Significant Change (CSC) at the critical point of HbA1c 7.0%-NGSP were determined. Within the analytical conditions of this study, only the immunoturbidimetric method had an acceptable analytical performance, allowing attribute a change in 0.5%-NGSP to a significant clinical variation. Faced with international recommendations on the use of HbA1c on control and diagnosis of diabetes, the importance of choosing a method that meets the minimum analytical quality requirements to ensure the clinical utility of HbA1c result is undeniable.


O laboratório deve garantir a precisão dos resultados da HbA1c cumprindo com os requisitos analíticos internacionais de qualidade cada vez mais exigentes e garantir que uma variação de HbA1c de 0,5 pontos percentuais (% - NGSP) ou mais entre duas verificações consecutivas de um doente diabético seja devido a uma variação clínica e não a uma variação analítica. Neste trabalho foi avaliado o desempenho analítico de três métodos comerciais para HbA1c: imunoturbidimétrico, enzimático e cromatográfico de intercâmbio catiônico. Para esse fim, foram processados diversos controles comerciais de HbA1c por cada método, com rastreabilidade ao método de referência IFCC, determinando em cada caso Quociente de Variação Total, Bias, Erro Total, Valor de Referência da Alteração e Alteração Clinicamente Significativa de HbA1c no ponto crítico 7,0%-NGSP. Nas condições de análise deste estudo, apenas o método imunoturbidimétrico teve um desempenho analítico aceitável, permitindo atribuir uma alteração de 0,5%-NGSP a uma variação clínica significativa do paciente. Perante as recomendações internacionais sobre o uso da HbA1c no controle e diagnóstico da diabetes, é inegável a importância de escolher um método que atenda os requisitos analíticos mínimos de qualidade de análise para garantir a utilidade clínica do resultado HbA1c.


Subject(s)
Humans , Analytical Quality Control/methods , Clinical Laboratory Techniques/standards , Chemistry Techniques, Analytical , Chromatography/standards , Clinical Enzyme Tests/standards , Diabetes Mellitus/diagnosis , Hemoglobin A , Immunoturbidimetry/standards , Quality Control
20.
Braz. j. pharm. sci ; 50(2): 229-242, Apr-Jun/2014. tab, graf
Article in English | LILACS | ID: lil-722179

ABSTRACT

The aim of this study was to evaluate two important aspects of patent applications of crystalline forms of drugs: (i) the physicochemical characterization of the crystalline forms; and (ii) the procedure for preparing crystals of the blockbuster drug clopidogrel. To this end, searches were conducted using online patent databases. The results showed that: (i) the majority of patent applications for clopidogrel crystalline forms failed to comply with proposed Brazilian Patent Office guidelines. This was primarily due to insufficient number of analytical techniques evaluating the crystalline phase. In addition, some patent applications lacked assessment of chemical/crystallography purity; (ii) use of more than two analytical techniques is important; and (iii) the crystallization procedure for clopidogrel bisulfate form II were irreproducible based on the procedure given in the patent application.


Este trabalho tem como objetivo avaliar dois aspectos importantes em um pedido de patente de formas cristalinas de fármacos: (i) caracterização físico-química das formas cristalinas e (ii)o procedimento de preparo da forma II do fármaco clopidogrel, um blockbuster de vendas. Realizaram-se buscas em bancos de dados patentários on line. Os resultados mostraram que (i) a maioria dos pedidos de patente de formas cristalinas do clopidogrel não se adequam com proposta do INPI devido ao número insuficiente de técnicas analíticas utilizadas na caracterização da fase cristalina. Ainda, em alguns pedidos de patente não há a presença da avaliação da pureza química/cristalográfica; (ii) a importância de se utilizar mais de duas técnicas de avaliação e (iii) que não foi possível a reprodução da cristalização com o procedimento apresentado no pedido de patente.


Subject(s)
Chemistry Techniques, Analytical/statistics & numerical data , Crystallins/classification , Patent , Chemical Phenomena , Platelet Aggregation Inhibitors/classification , Polymorphism, Genetic
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