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1.
Eur. j. anat ; 24(3): 211-220, mayo 2020. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-ET2-5391

RESUMO

Cardiac malformations are very prevalent and can be caused both by defective genes and envi-ronmental teratogens. Among the latter, caffeine causes malformations when exposed during early cardiac development, whereas its later effects are still unclear. We exposed three-day incubated (D3) chick embryos to 2 mg caffeine and analyzed them at D5, D7 and D9. The embryos were serially sec-tioned and analyzed two-dimensionally. Alternatively, the sections of D9 embryos were reconstructed three-dimensionally using Amira® software and analyzed volumetrically. The expres-sion of genes involved in endothelial-mesenchymal transformation (EMT) was studied by real-time PCR. Interestingly, caffeine treatment at D3 em-bryos did not induce cardiac malformations, but did delay growth, in particular that of the ventricles and ventricular trabeculae. Furthermore, it affected EMT in the endocardial cushion and atrioventricu-lar valves. Gene-expression analysis revealed that caffeine had a progressively deleterious effect on the expressions of GATA4, MMP2, SNAIL1, TWIST1, and VIMENTIN. The effect of late caf-feine administration on the chicken embryos would provide suggestive evident towards a possible heart developmental defect in humans, particularly heavy caffeine consumers during pregnancy


No disponible


Assuntos
Animais , Embrião de Galinha/efeitos dos fármacos , Cafeína/administração & dosagem , Cardiopatias Congênitas/induzido quimicamente , Cardiopatias Congênitas/genética , Embrião de Galinha/anatomia & histologia , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Análise de Dados , Titulometria/métodos , Ecocardiografia Tridimensional , Anatomia Transversal
2.
Chemosphere ; 254: 126686, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32320830

RESUMO

A poly(l-serine)-modified glassy carbon electrode (PLS/GCE) was fabricated by electropolymerization and used to study the detection of naproxen (NPX), a representative non-steroidal anti-inflammatory drug, in phosphate buffer supporting electrolyte at pH 5.0. Results indicated that the PLS/GCE was capable of determination of NPX at a working potential of 0.92 (vs. Ag/AgCl) in voltammetry mode. Experimental factors such as scan rate, accumulation time, solution pH, initial NPX concentration, and interferences were optimized for NPX determination efficiency. The morphology and elemental distribution of the electrode surface were characterized by ESEM, TEM, PSD, XRD, FTIR, TGA, XPS, and zeta potential. NPX oxidation current increased with increasing analyte concentration and scan rate but decreased with increasing pH. Linear sweep voltammetry calibration curve was established in the NPX concentration range of 4.3-65 µM, with detection limit and average recovery of 0.69 µM (n = 3) and 104 ± 2.5%, respectively. PLS/GCE is simple, accurate, reproducible, and easy for operation, therefore would be cost-effective for the determination of NPX.


Assuntos
Naproxeno/química , Poluentes Químicos da Água/química , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Naproxeno/análise , Oxirredução , Fosfatos , Serina , Titulometria
3.
Talanta ; 206: 120219, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514888

RESUMO

A new method to determine the total titratable acidity of orange, lemon and passion fruit, based on a spot test obtained from digital images and using anthocyanins as the biodegradable indicator, is presented for the first time. The colorimetric reactions were carried out by acid-base titration on a microscale, employing anthocyanin with a microplate for spot test purposes, with detection by digital imaging. To obtain highly precise data, a chamber based on a diffuser was developed to control the illumination supplied by the light emitting diodes, and coupled to a smartphone to acquire adequate digital images. High precision was obtained with a relative standard deviation of 0.758% for n = 95. The RGB values were extracted from the digital images and used as analytical signals, the values being correlated with the micro-volume of the titrant and used to construct the titration curves and obtain the first and second derivatives, respectively. For comparative purposes, the official AOAC (Association of Official Analytical Chemists) and MAPA (Ministry of Agriculture, Livestock and Food Supply of Brazil) methods were used and the results compared by applying the paired t-test at the 95% confidence level (n = 3). No difference was found between the values and the relative errors were less than 2.8%. The micro-titrimetric method was fast, uses anthocyanins as the natural indicator, is practical, and permits a reduction of 922 times or 99.9% of the volume required in a conventional titration. It is therefore ideal for routine analyses leading to a reduction in the waste generated, according to the principles of green chemistry.


Assuntos
Citrus sinensis/química , Frutas/química , Passiflora/química , Antocianinas/química , Colorimetria/instrumentação , Colorimetria/métodos , Química Verde/métodos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Phaseolus/química , Smartphone , Titulometria/instrumentação , Titulometria/métodos
4.
Mutat Res ; 845: 402981, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31561901

RESUMO

The enzyme-modified comet assay is a commonly used method to detect specific DNA lesions. However, still a lot of errors are made by many users, leading to dubious results and even misinterpretations. This technical note describes some critical points in the use of the enzyme-modified comet assay, such as the enzyme concentration, the time of incubation, the format used and the equipment. To illustrate the importance of these conditions/parameters, titration experiments of formamidopyrimidine DNA glycosylase (Fpg) were performed using the 2 gels/slide and the 12 minigels/slide formats (plus the 12-Gel Comet Assay Unit™). Incubation times of 15 and 30 min, and 1 h were used. Results showed that the 12 minigels/slide system requires a lower volume and concentration of Fpg. A longer time of incubation has a bigger impact when using such format. Moreover, the paper describes how to perform and interpret a titration experiment when using the enzyme-modified comet assay.


Assuntos
Ensaio Cometa/métodos , DNA-Formamidopirimidina Glicosilase/farmacologia , Titulometria/métodos , 8-Hidroxi-2'-Desoxiguanosina/análise , Alquilantes/toxicidade , Linhagem Celular , Ensaio Cometa/instrumentação , Dano ao DNA , Relação Dose-Resposta a Droga , Eletroforese em Gel de Ágar , Géis , Humanos , Linfócitos/efeitos dos fármacos , Reprodutibilidade dos Testes , Fatores de Tempo
5.
Yakugaku Zasshi ; 139(9): 1195-1200, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31474635

RESUMO

In this study, we attempted to improve the non-aqueous titration method using N,N-dimethylformamide (DMF) in the Japanese Pharmacopoeia seventeenth edition (JP XVII) for advancement in experimental safety. As an alternative solvent for DMF, we demonstrate titrations using dimethyl sulfoxide (DMSO), which has similar properties as and much higher safety than DMF. Five drugs (i.e., acetohexamide, glibenclamide, sulfamethoxazole, tranilast, and furosemide) listed in JP XVII use DMF as a solvent for titrations with sodium hydroxide standard solution. For these drugs, we examined whether DMF can be replaced with DMSO in quantitative analyses. As a result, a quantification similar to that of the Pharmacopoeia protocol is possible by simply replacing DMF with DMSO or using a mixed solvent of DMSO and water.


Assuntos
Dimetil Sulfóxido , Dimetilformamida , Farmacopeias como Assunto , Melhoria de Qualidade , Segurança , Solventes , Titulometria/métodos , Japão , Hidróxido de Sódio , Soluções , Água
6.
Rev. argent. radiol ; 83(3): 95-101, set. 2019. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1057407

RESUMO

Objetivo Desde la aparición de la tractografía, al tratarse de una técnica no invasiva y que usa la ampliamente conocida resonancia magnética (RM), el estudio de la sustancia blanca se ha facilitado. A partir de eso, se han logrado grandes descubrimientos en cuanto a fascículos cerebrales involucrados en funciones cognitivas. Sin embargo, su evaluación sigue siendo subjetiva y depende de la experiencia y entrenamiento del evaluador, razón por la cual se ha limitado su aplicabilidad en la práctica clínica. En ese sentido, es conveniente parametrizar volúmenes cerebrales de sustancia blanca en población sana a través de una herramienta electrónica que se pueda reproducir y así poderlo aplicar en enfermos. Materiales y métodos Se reportan 10 sujetos sanos desde el punto de vista neurológico. Para cada sujeto, se adquirieron imágenes ponderadas por difusión y los resultados se visualizaron mediante FiberNavigator (http://scilus.github.io/fibernavigator). Finalmente, esa misma herramienta fue utilizada para purificar los fascículos objeto de estudio y realizar el conteo de las fibras. Resultados Se obtuvieron valores de volumetría del fascículo longitudinal superior (FLS), fascículo longitudinal inferior (FLI), fascículo frontoccipital inferior (FFI), fascículo uncinado (FU) y fascículo del cíngulo (FC), identificando que no existen diferencias estadísticamente significativas entre el número de fibras que componen los fascículos cerebrales. Discusión Los resultados alcanzados de la anatomía y la direccionalidad de fibras de los fascículos cerebrales de este estudio coinciden con el resto de la evidencia publicada hasta el momento, sin encontrar diferencias en cuanto a su organización y recorrido. Conclusión Aunque esos resultados no sirven como valores de referencia para ser aplicados en pacientes con patología neurológica, brindamos información inexistente hasta el momento, con ese equipo en específico y la reproducción entre los distintos usuarios y el software.


Objective Since the appearance of tractography, as it is a non-invasive technique and uses the widely known magnetic resonance (MR), the study of white matter has been facilitated. After this, great discoveries have been made regarding the brain fascicles involved in cognitive functions. However, its evaluation continues to be subjective and depends on the evaluator's experience and training. That the reason why its applicability has been limited in clinical practice. Because of this, it is convenient to parametrize cerebral volumes of white matter in healthy population through an electronic, reproducible tool that could be applied in patients. Materials and Methods Ten neurologically healthy subjects are reported, for each subject we acquired images weighted by diffusion and the results were visualized by means of FiberNavigator (http://scilus.github.io/fibernavigator). Finally, this same tool was used to purify the fascicles under study and perform the fiber count. Results Volumetric values of the upper longitudinal fasciculus, inferior longitudinal fasciculus, inferior frontoccipital fasciculus, uncinated fasciculus and cingulate fasciculus were obtained, identifying that there are not statistically significant differences in the number of fibers that make up the cerebral fascicles. Discussion The results achieved of the anatomical and fiber directionality of the cerebral fascicles of this study, coincide with the rest of the evidence published up to now, without finding differences regarding its organization and route. Conclusion Although these results do not serve as reference values to be applied in patients with neurological pathology, do we provide nonexistent information so far, with this specific equipment and the reproducibility between the different users and the software.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Cognição/fisiologia , Substância Branca/diagnóstico por imagem , Valores de Referência , Anisotropia , Titulometria/normas , Imagem de Tensor de Difusão/normas , Fibras Nervosas
7.
J Food Sci ; 84(8): 2165-2170, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313309

RESUMO

To determine the total acidity in freshly squeezed fruit juice, we miniaturized the potentiometric titrations and achieved better accuracy compared with titrations from a conventional pH probe. The improvement was the result of a higher jump in pH at the endpoint due to a reduction in the dilutions of both the titrand and titrant. A conventional pH probe requires more than 50 mL of titrand, which can lead to a 25000-fold dilution of the titrant when adding the titrant at 2 µL intervals. Conversely, when the volume of the titrand can be reduced to 1 mL, the dilution is only 500-fold, which results in a higher jump in pH at the endpoint. The concentration of the titrant, NaOH, was optimized by titrating sample solutions containing 25 and 50 mM of citric acid. The addition of 5 M NaOH in intervals of 2 µL led to a more accurate endpoint for both 25 and 50 mM citric acid solutions. Miniaturization of the titration process is advantageous in terms of portability, accuracy, and in requiring less consumption of a sample, thereby simplifying the process of repeat measurements that are helpful in evaluating the precision of analytical results. Practical samples of squeezed fruit juices were titrated via three methods that showed no significant differences: classic titrimetry with an indicator, conventional potentiometry, and miniaturized potentiometry. This process would be effective for use in the field and in developing countries. PRACTICAL APPLICATION: The total acidity of fruits and fruit juices is an important indicator of quality and is generally expressed in terms of the citric acid content. However, a standard potentiometric titration requires a large sample volume, which makes it difficult to assess dispersion of the acidity for individual fruits. The results of this study indicate that the use of miniaturized potentiometric titration could benefit food chemistry in many developing countries in addition to opening new fields of food chemistry such as on-site quality control of citrus fruit and evaluation of variations in quality.


Assuntos
Ácido Cítrico/análise , Sucos de Frutas e Vegetais/análise , Potenciometria/métodos , Citrus/química , Frutas/química , Concentração de Íons de Hidrogênio , Titulometria/métodos
8.
An Real Acad Farm ; 85(2): 123-152, abr.-jun. 2019. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-186172

RESUMO

En este trabajo se pasa revista a la vida y obra de autores farmacéuticos y médicos no contemplados en contribuciones previas recientemente publicadas en estos Anales, detallando de manera especial sus aportaciones al análisis volumétrico. Las determinaciones de la materia orgánica en aguas debida al danés Forchhammer, de la dureza del agua llevada a cabo por el escocés Clark y los franceses Boutron y Boudet, de hierro con dicromato realizada por el ingles afincado en Escocia Frederick Penny, y la argentométrica de cianuro modificada por el francés Denigés, se encuentran entre las aportaciones más destacadas. El trabajo cubre el periodo que abarca desde el siglo XVII, e.g. Newman hasta la primera década del siglo XX, e.g. Szily. La química analítica durante ese período, como indica Labrude, ha constituido siempre una de las preocupaciones y de las actividades importantes de los farmacéuticos


In this paper we review the life and work of pharmaceutical and medical authors not included in previous contributions recently published in these Annals, detailing in a special way their contributions to the trimetric analysis. The determinations of the organic matter in waters due to the Danish Forchhammer, of the hardness of the water carried out by the Scottish Clark and the French Boutron and Boudet, of iron with dichromate made by the Englishman living in Scotland Frederick Penny, and the argentometrics of cyanide modified by the French Denigés, are among the most outstanding contributions. The paper covers the period from the seventeenth century, e.g. Newman to the first decade of the twentieth century, e.g. Szily. Analytical chemistry during this period, as indicated by Labrude, has always been one of the concerns and important activities of pharmacists


Assuntos
Humanos , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , Preparações Farmacêuticas , Titulometria/história , Farmacêuticos/história , Médicos/história
9.
Nat Commun ; 10(1): 2062, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048680

RESUMO

The prediction of implant behavior in vivo by the use of easy-to-perform in vitro methods is of great interest in biomaterials research. Simulated body fluids (SBFs) have been proposed and widely used to evaluate the bone-bonding ability of implant materials. In view of its limitations, we report here a rapid in vitro method based on calcium titration for the evaluation of in vivo bioactivity. Using four different titanium surfaces, this method identifies that alkaline treatment is the key process to confer bioactivity to titanium whereas no significant effect from heat treatment is observed. The presence of bioactive titanium surfaces in the solution during calcium titration induces an earlier nucleation of crystalline calcium phosphates and changes the crystallization pathway. The conclusions from this method are also supported by the standard SBF test (ISO 23317), in vitro cell culture tests using osteoblasts and in vivo animal experiments employing a pelvic sheep model.


Assuntos
Materiais Biocompatíveis/química , Teste de Materiais/métodos , Próteses e Implantes , Titânio/química , Animais , Interface Osso-Implante , Cálcio/química , Células Cultivadas , Feminino , Modelos Animais , Osseointegração , Osteoblastos , Implantação de Prótese , Ovinos , Propriedades de Superfície , Fatores de Tempo , Titulometria/métodos
10.
Drug Test Anal ; 11(7): 1065-1075, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30912309

RESUMO

For assurance of the quality of active pharmaceutical ingredients (APIs) used for manufacturing medicines, the analytical requirements of the European Pharmacopoeia serve as a guideline and have a binding character. Within a particular timeframe, an API is considered to comply with predefined specifications. If applicable, it can be used for the manufacturing of a finished pharmaceutical product. The objective of the study presented here was to assess the long-term stability of 50 drug substances with an age of 20-30 years or even older in some cases. The substances are part of a collection of old pharmaceuticals at the Institute for Pharmacy in Würzburg, Germany, and represent commonly used drug classes containing ß-blockers, ß-sympathomimetic drugs, anticholinergics, anti-infectives, non-steroidal anti-inflammatory drugs, antipsychotics, antihistaminic drugs, and one antiarrhythmic drug. The content and the degradation profile of the items were determined by means of potentiometric titration and liquid chromatography techniques based on pharmacopoeial approaches for impurity profiling covering all process and degradation related substances. The results of the study show that 44 out of 49 tested substances still complied with specifications of the current pharmacopoeias. For metipranolol, which is not monographed in any pharmacopoeia, a small degradation by hydrolysis was observed. In one lot of ampicillin sodium, atenolol, atropine, penbutolol, and salbutamol, at least one impurity did not meet the acceptance criteria, respectively. Some impurities were not related to degradation. However, a surprisingly high chemical stability of the old drug substances was revealed after more than two decades of storage.


Assuntos
Estabilidade de Medicamentos , Preparações Farmacêuticas/química , Cromatografia Líquida , Contaminação de Medicamentos , Indústria Farmacêutica , Potenciometria , Controle de Qualidade , Fatores de Tempo , Titulometria
11.
J Chromatogr A ; 1597: 220-224, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30876739

RESUMO

Titration methods are routinely used in the laboratories for the quantification of acids and bases, for the complexometric determination of metal ions and for the ion-pair titrations of drugs in pharmaceutical control. They also find application in a wide variety of chemical and biochemical studies. However, conventional titration methods (CTM) require large amounts of samples that are not always available. In absence of micro-titrator devices, the application of these methods for expensive samples and for small batch sizes is not possible. In this work, it was demonstrated that the commercial capillary electrophoretic apparatus (CEa) can be used, in a quick and easy way, for the end-point detection in a microtitration process. The proposed methodology exploits the change of the solutions conductivity during the titrations. The equivalent points can be easily located by plotting the change in electrical current as a function of the titrant volume added. More interestingly, only 1.1-1.5 mL of analyte solutions are required to establish the titration curves. The advantages and the limitations of the procedure are discussed in detail.


Assuntos
Condutividade Elétrica , Eletroforese Capilar , Titulometria/métodos , Íons/análise , Metais/análise , Titulometria/normas
14.
Food Chem ; 282: 147-152, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30711099

RESUMO

The statistical method of random uncertainties has been adopted for the uncertainty calculation of chemical measurements, since it is a good estimator of the overall uncertainty. Type B (inherited) uncertainties are usually insignificant when compared to type A (experimental) uncertainties. In quantitative measures, the mean is the most probable value of the measurand and the standard deviation of the mean is the best estimate of its standard uncertainty. Measurement uncertainty of qualitative measures may be estimated by the probability of taking right or wrong decisions. Thus, performance data of analytical methods are the main source of uncertainties. However, uncertainties obtained from limited observations should be used with caution to represent the overall uncertainty. This study demonstrated the influence of random uncertainties on the results of experimental approaches to estimate the uncertainty in chemical assays. The different profiles of uncertainty were demonstrated depending on the analytical technique and food composition.


Assuntos
Análise de Alimentos/métodos , Conservantes de Alimentos/análise , Limite de Detecção , Sulfitos/análise , Titulometria , Incerteza
15.
ACS Sens ; 4(1): 126-133, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30604605

RESUMO

Enzyme-linked immunosorbent assays (ELISAs) have been widely used in clinical examination, food safety, and environmental analyses. However, they still face a great challenge in designing a device for a point-of-care test (POCT) due to its bulk optical detector and complexity. Herein an electrophoresis titration (ET) model of a moving redox boundary (MRB) was proposed for constructing an ET-ELISA chip of a POCT just with sextuplet electrode pairs and laminated cells. The chip had an anodic well, middle well, and cathode well which were connected by microchannels. The ELISA process was conducted in the bottom of the middle well, where horseradish peroxidase (HRP) catalyzed 3,3',5,5'-tetra-methyl benzidine (TMB) as a blue TMB dimer with two positive charges. Under an electrical field of 29 V, the TMB dimer migrated into the titration channel and reacted with the ascorbic acid, creating an MRB. The MRB motion was a function of antigen content, indicating a visual distance-based assay. As a proof of concept, a C-reactive protein was chosen as a model antigen. The experiments systemically validated the ET-ELISA model and method. Particularly, the chip was smartphone-detected, traditional power supply free, and did not use sulfuric acid used in typical ELISA, making the ET-ELISA method extremely simple, portable, and safe. The ET-ELISA has great potential to visual and portable ELISA in clinical medicine, the environment, and food safety immunoassay.


Assuntos
Proteína C-Reativa/análise , Ensaio de Imunoadsorção Enzimática/métodos , Dispositivos Lab-On-A-Chip , Titulometria/métodos , Armoracia/enzimologia , Benzidinas/química , Ensaio de Imunoadsorção Enzimática/instrumentação , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Oxirredução , Testes Imediatos , Estudo de Prova de Conceito , Smartphone , Titulometria/instrumentação
16.
Anal Sci ; 35(3): 347-350, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30344207

RESUMO

We propose the creation of reusable indicator-sorbed-solids, using anion-exchange resins or kaolin as supports, with the aim to reduce chemical use towards green analytical chemistry. Indicators (phenolphthalein, thymol blue and butterfly pea flower extract as a natural indicator) sorbed on a solid support, were employed in acid-base titration, in both homogenous aqueous and heterogenous aqueous organic phases. Applications of the developed techniques to some real samples, such as vinegar, colored fruit juice and vegetable oil, have been demonstrated.


Assuntos
Resinas de Troca de Ânions/química , Análise de Alimentos/métodos , Química Verde/métodos , Indicadores e Reagentes/química , Caulim/química , Titulometria/métodos , Ácido Acético/análise , Adsorção , Sucos de Frutas e Vegetais/análise , Óleos Vegetais/análise
17.
Colloids Surf B Biointerfaces ; 175: 195-201, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30530005

RESUMO

The reductive detoxification of microbes is of significant importance as toxic high oxidation-state metals are ubiquitous in the environment. As a protective interface, extracellular polymeric substances (EPS) are known to play an important role in reducing the toxicity, the relative contribution of different EPS fractions in the process of microbial reductive detoxification remains not to be understood. In this study, we used toxic gold ions (Au3+) and EPS fractions from Paenibacillus mucilaginosus as an example to quantitatively assess the relative contribution of different EPS fractions in the process of the reductive detoxification. At different concentrations of EPS (300 mg/L to 500 mg/L), B-EPS contributed higher reductive ratio (10.6%±0.6% to 25.9%±0.3%) for reducing the toxicity of Au3+, while it was lower (1.7%±0.3% to 5.4%±0.6%) for L-EPS. Confronted with the attack of the Au3+ ions (0 ppm-180 ppm), sugars in B-EPS had a more positive metabolic response than proteins (secreted sugars/ proteins>1) against the toxicity of Au3+. Ultimately, FTIR and electrochemical titration analyses showed that the detoxification process of microbial EPS was mainly mediated by the aldehyde groups of sugars in B-EPS. This study contributed a quantitative understanding for the role of different fractions of EPS in microbial defense against the attack of toxic metal ions.


Assuntos
Matriz Extracelular de Substâncias Poliméricas/química , Ouro/química , Íons/química , Paenibacillus/química , Biodegradação Ambiental , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Matriz Extracelular de Substâncias Poliméricas/ultraestrutura , Ouro/toxicidade , Íons/toxicidade , Microscopia Eletrônica de Transmissão , Paenibacillus/efeitos dos fármacos , Paenibacillus/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Titulometria
18.
Transfusion ; 58 Suppl 3: 3065-3071, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30536437

RESUMO

BACKGROUND: To ensure that immunoglobulin (Ig) products have adequate functional antibody, the US Food and Drug Administration (FDA) requires that Ig lots contain minimum levels of measles neutralizing antibody; the current minimum is 0.48 x US Reference Ig 176. STUDY DESIGN AND METHODS: In the first part of the study, measles antibody titers were measured in donor plasma samples collected in 2007, 2011, and 2017. In the second part, trough or steady-state serum levels of measles neutralizing antibody were measured in two studies of patients with primary immunodeficiency (PID) who were treated with intravenous (Study 1; N = 46) or subcutaneous (Study 2; N = 18) Ig replacement therapy, meeting previous requirements for lot potency (≥0.6 x US Reference Ig 176). Serum measles neutralizing antibody titers were then estimated for conditions in which the potency of the Ig replacement product was 0.48 or 0.30 x US Reference Ig 176. RESULTS: Measles antibody titers in donated plasma samples declined in donors born after 1963. In the two studies of patients with PID who were treated with intravenous or subcutaneous Ig replacement therapy, all patients exhibited trough (intravenous Ig) or steady-state (subcutaneous Ig) measles neutralizing antibody titers above 0.12 IU/mL, which has been shown to protect against clinical measles in the general population. Estimates suggest that all patients except one would have continued to meet this standard if the Ig lot potency had been 0.48 or 0.30 x US Reference Ig 176. CONCLUSION: These studies provide supporting evidence that the lot release specification can be safely lowered from 0.48 to 0.30 x US Reference Ig 176, which will accommodate declining measles neutralizing antibody levels in donor plasma.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Imunoglobulinas/administração & dosagem , Síndromes de Imunodeficiência/terapia , Vacina contra Sarampo , Sarampo/prevenção & controle , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/análise , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulinas/sangue , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/sangue , Síndromes de Imunodeficiência/imunologia , Estudos Longitudinais , Masculino , Sarampo/imunologia , Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/sangue , Vacina contra Sarampo/imunologia , Pessoa de Meia-Idade , Testes Sorológicos , Titulometria , Vacinação , Potência de Vacina , Adulto Jovem
19.
Transfusion ; 58 Suppl 3: 3090-3095, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30536431

RESUMO

BACKGROUND: Immunoglobulins (Igs) have been in clinical use for almost 70 years, and early on were also used in conjunction with exposure to the measles virus or polio virus. The US regulations that describe functional Ig lot release thus require the demonstration of minimum antibody titers against these two viruses, although the use of vaccines has now dramatically reduced their incidence. The lower clinical importance of these viruses raises the question of whether other virus antibodies might be more informative for patients with immunodeficiency. STUDY DESIGN AND METHODS: A literature survey was conducted to identify viruses of potential clinical concern for people with immunodeficiency. The viruses selected have stable seroepidemiology and associated functional antibody assays. As a result, neutralizing antibody titers to human adenovirus 5 (HAdV5), respiratory syncytial virus (RSV) serotypes A and B, and human parainfluenza virus 3 (hPIV3) were determined in Ig lots produced from plasma collected in either the United States or the European Union. RESULTS: The virus antibody titers measured were high and consistent among the Ig lots tested. Use of either US- or EU-derived plasma as starting material resulted in equivalent virus antibody titers, with the exception of RSV serotype B, for which a lower titer was seen in EU plasma-derived Ig lots. CONCLUSION: With the significant decline in measles virus and polio virus circulation, and even their potential eradication, measurement of antibody titers against other viruses in Ig products may be more informative for functional lot release testing.


Assuntos
Anticorpos Antivirais/análise , Imunoglobulinas/análise , Testes Sorológicos , Anticorpos Antivirais/sangue , Humanos , Imunoglobulinas/sangue , Sarampo/sangue , Sarampo/prevenção & controle , Morbillivirus/imunologia , Poliomielite/sangue , Poliomielite/prevenção & controle , Poliovirus/imunologia , Testes Sorológicos/métodos , Testes Sorológicos/tendências , Titulometria/métodos , Titulometria/tendências
20.
An Real Acad Farm ; 84(4): 337-345, oct.-dic. 2018. ilus
Artigo em Espanhol | IBECS | ID: ibc-178130

RESUMO

La contribución más importante en el ámbito de la iodometría se debe a Bunsen, quien describe la determinación de una amplia variedad de sustancias oxidantes liberando el yodo a partir del ioduro potasio, y valorándolo con ácido sulfuroso. Bunsen tenía predilección por el trabajo cuantitativo y era un genio en el diseño de la ciencia aplicada aunque no patenta los dispositivos que idea. Da un impulso decisivo a la institucionalización de la farmacia alemana en el siglo XIX, interesándose por el desarrollo de la educación farmacéutica. Heinrich Schwarz tras estudiar en de Halle y pasar por Giessen marcha al laboratorio de Pelouze en París, donde se familiariza con los métodos volumétricos de análisis, trabajando a su regreso a Alemania en este campo. Propone reemplazar el ácido sulfuroso utilizado por Bunsen en las valoraciones con yodo por tiosulfato sódico, lo que supuso un gran avance. Theophile Pelouze, farmacéutico, es fundamental para entender las conexiones con Schwarz y también con Bunsen. El trabajo concluye con la determinación de azúcares propuesta por Arthur Barreswill modificada por Fehling, y con la determinación de la pureza del ioduro de potasio del comercio


The most important contribution in the field of iodometry is due to Bunsen, who describes the determination of a wide variety of oxidizing substances by releasing iodine from iodide potassium, and assessing it with sulphurous acid. Bunsen had a predilection for quantitative work and was a genius in the design of applied science, although he does not patent the devices that idea. It gives a decisive impulse to the institutionalization of the German pharmacy in the 19th century, taking an interest in the development of pharmaceutical education. Heinrich Schwarz after studying in Halle and going through Giessen goes to the Pelouze laboratory in Paris, where he becomes familiar with the volumetric methods of analysis, working on his return to Germany in this field. It proposes to replace the sulphurous acid used by Bunsen in the evaluations with iodine by sodium thiosulphate, which represented a great advance. Theophile Pelouze, pharmacist, is essential to understand the connections with Schwarz and also with Bunsen. The work concludes with the determination of sugars proposed by Arthur Barres will modified by Fehling, and with the determination of the purity of the potassium iodide of the trade


Assuntos
História do Século XIX , Iodo , Iodeto de Potássio , Tiossulfato Sódico de Ouro/história , Tiossulfato Sódico de Ouro/uso terapêutico , Titulometria/métodos , Pesquisa Aplicada , Educação em Farmácia/história
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