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1.
J Vet Emerg Crit Care (San Antonio) ; 31(2): 269-273, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33709630

RESUMO

OBJECTIVE: The objective of this study was to evaluate the biochemical and blood gas alterations of whole blood of buffaloes that was stored in citrate-phosphate-dextrose with adenine (CPDA-1) and CPD/SAG-M blood bags for 42 days. DESIGN: Prospective study. INTERVENTIONS: Ten male buffaloes were used in this study. A total volume of 900 mL of blood was collected from each buffalo so that 450 mL was stored in CPDA-1 and 450 mL was stored in CPD/SAG-M bags at 2-6°C for 42 days. The stored blood was evaluated at 7 time points (D): D0 (immediately after blood collection) and 7 (D7), 14 (D14), 21 (D21), 28 (D28), 35 (D35), and 42 (D42) days after collection. Blood gas, biochemical, and microbiological parameters were monitored. MEASUREMENTS AND MAIN RESULTS: The overall blood pH decreased from 6.997 ± 0.05 at D0 to 6.784 ± 0.09 at D42, differing from baseline from D14 onward (P < 0.05). There were increases in partial pressure of oxygen (pO2 ), partial pressure of carbon dioxide (pCO2 ), lactate, and potassium (K) and decreases in the concentrations of sodium, bicarbonate, glucose, and pH (P < 0.05) during storage in both bags but no alterations in total protein concentration. Most of the variables were consistently similar between the 2 types of blood bags (P > 0.05) evaluated, with the exception of pCO2 , HCO3, cholesterol, and total protein, which had higher values in the CPDA-1 bag (P < 0.05). The K, pO2 , and lactate had the highest alterations during storage, with increases from baseline to D42 of 563%, 317%, and 169%, respectively. CONCLUSION: In general, no significant changes of clinical importance were observed after storage of whole blood samples from buffaloes for 42 days in the 2 types of blood bags that are indicated for use with this species.


Assuntos
Anticoagulantes/farmacologia , Preservação de Sangue/veterinária , Búfalos/sangue , Citratos/farmacologia , Glucose/farmacologia , Adenina , Animais , Anticoagulantes/química , Citratos/química , Eritrócitos , Glucose/química , Masculino , Fosfatos , Potássio/sangue , Estudos Prospectivos
2.
Methods Mol Biol ; 2118: 3-20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32152967

RESUMO

The increasing impact of metallic nanoparticles on life sciences has stimulated the development of new techniques and multiple improvements to the existing methods of manufacturing nanoparticles with tailored properties. Nanoparticles can be synthesized through a variety of physical and chemical methods. The choice of preparation procedure will depend on the physical and chemical characteristics required in the final product, such as size, dispersion, chemical miscibility, and optical properties, among others. Here we review basic practical procedures used for the preparation of protected and unprotected metallic nanoparticles and describe a number of experimental procedures based on colloidal chemistry methods. These include gold nanoparticle synthesis by reduction with trisodium citrate, ascorbic acid, or sugars in aqueous phase and nanoparticle passivation with alkanethiols, CTAB, or BSA. We also describe microwave-assisted synthesis, nanoparticle synthesis in ethylene glycol, and template-assisted synthesis with dendrimers, and, briefly, how to control nanoparticle shape (star-shaped and branched nanoparticles).


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Ácido Ascórbico/química , Citratos/química , Micro-Ondas , Tamanho da Partícula
3.
Ann Nucl Med ; 34(4): 263-271, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32076955

RESUMO

AIM: The main goal in Crohn´s disease (CD) is a sustained suppression of inflammatory activity associated with mucosa healing in endoscopic evaluation. During clinical routine, there are small numbers of good markers to monitor inflammatory activity under treatment. We postulated that Oral 67Gallium Citrate Scintigraphy is able to mark inflammatory disease in mucosa and deep inflammation in CD, when used in oral form. OBJECTIVE: Measure the accuracy of Oral 67Gallium Citrate Scintigraphy in intestinal inflammatory activity of Crohn´s disease. PATIENTS AND METHODS: In a prospective consecutive cross-sectional study from January 2018 to June 2019, the ileocolonic region of 32 patients with CD were studied by dividing into four regions of interest (ROI) from the ileum to the rectum. A total of 128 intestinal segments were analyzed in cluster data. Accuracy values of Oral 67Gallium Scintigraphy and colonoscopy tests were evaluated with the histological reference test. Values of the respective receiver operating characteristic (ROC) curves were obtained  and compared. The reliability between the tests was evaluated by Kappa statistical with the segment-level analyses using variance adjustments. All statistical analyses were performed with a test significance level of 0.05. RESULTS: The study population included 32 patients with CD (10 men, 22 women; average age 39 years). Disease time was five years on average. Anti-TNFs treatment was found in 71%. The most found phenotype of the Montreal classification was L3. Differences in ROC curves for colonoscopy (0.94) and Oral 67Ga Scintigraphy (0.96) did not show significant value (p = 0.32). The sensitivity of scintigraphy to detect intestinal inflammatory activity in CD was 64%, specificity of 96% and accuracy of 84%. A high agreement was found between oral scintigraphy and histological measurements with kappa = 0.64. CONCLUSIONS: Oral 67Ga Scintigraphy had similar accuracy and agreement compared to colonoscopy in the identification of inflammatory activity in Crohn´s Disease. This new approach may be useful and less invasive for long term follow-ups.


Assuntos
Citratos/administração & dosagem , Doença de Crohn/complicações , Radioisótopos de Gálio/administração & dosagem , Gálio/administração & dosagem , Inflamação/diagnóstico por imagem , Cintilografia/métodos , Administração Oral , Adulto , Antineoplásicos/farmacologia , Citratos/química , Estudos Transversais , Feminino , Gálio/química , Radioisótopos de Gálio/química , Humanos , Íleo/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/química , Reto/metabolismo , Reprodutibilidade dos Testes , Medição de Risco , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo
4.
Biometals ; 32(1): 139-154, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30623317

RESUMO

Phytoplankton blooms can cause acute effects on marine ecosystems due either to their production of endogenous toxins or to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of these Harmful Algal Blooms are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable source of iron for phytoplankton which could in turn stimulate algal growth and support bloom dynamics. Here we correlate iron concentrations, phytoplankton cell counts, bacterial cell abundance, and copy numbers for a photoactive siderophore vibrioferrin biosynthesis gene in water samples taken from 2017 cruises in the Gulf of California, and the Pacific Ocean off the coast of northern Baja California as well as during a multiyear sampling at Scripps Pier in San Diego, CA. We find that bacteria producing the photoactive siderophore vibrioferrin, make up a surprisingly high percentage of total bacteria in Pacific/Gulf of California coastal waters (up to 9%). Vibroferrin's unique properties and the widespread prevalence of its bacterial producers suggest that it may contribute significantly to generating bioavailability of iron via photoredox reactions.


Assuntos
Citratos/biossíntese , Ferro/metabolismo , Marinobacter/química , Sideróforos/biossíntese , California , Citratos/química , Ferro/química , Marinobacter/metabolismo , México , Pirrolidinonas/química , Sideróforos/química
5.
Electrophoresis ; 38(15): 1860-1868, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28387965

RESUMO

Capillary electrophoresis (CE) is an extremely effective technique in many kinds of separations, including separation of enantiomers. Some additional techniques may be necessary to determine the enantiomer migration order (EMO) and also the mechanism involved in chiral recognition. This paper reports the development and optimization of a CE method for enantioseparation of racemic mixture of both R- and S-stereoisomers of tramadol (TRM) with a computational contribution for the EMO determination and the responsible mechanisms for chiral distinction. Parameters such as composition and concentration of background electrolyte (BGE) and type and concentration of cyclodextrins (CD) were evaluated. For calculations, a sequential methodology was used, resorting to semiempirical Parametric Model 3 (PM3) followed by calculations accomplished using density functional theory. The best results were obtained with sulfated-ß-CD (s-ß-CD) and carboxymethyl-ß-cyclodextrin (cm-ß-CD) as chiral selector. Calculations show that the inclusion of TRM is not a probable process due to the shape of the TRM molecule and the size CDs cavities. Therefore, the chiral recognition process occurs by the formation of association complexes between modified ß-CD and groups of TRM molecules. The structural analysis of the fragments of complexes at a pH of 10 and a thermodynamic analysis of the complexes' formation process allows determining the EMO. Comparing results obtained experimentally and computationally, it seems that the developed method is adequate for separation of TRM enantiomers and the computational methodology is also adequate to get a sense of the system at a molecular level.


Assuntos
Eletroforese Capilar/métodos , beta-Ciclodextrinas/química , Citratos/química , Eletroforese Capilar/instrumentação , Concentração de Íons de Hidrogênio , Modelos Moleculares , Estereoisomerismo , Termodinâmica , Tramadol/análise , Tramadol/química , Tramadol/isolamento & purificação
6.
Protein Expr Purif ; 129: 25-30, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27623151

RESUMO

The structure and catalytic activity of xylanase from Thermomyces lanuginosus were studied in different media (containing polyethylene glycol -PEG- or salt) at different temperatures. The aim was to study how the native structure of the enzyme is affected to understand the partitioning behavior of xylanase in PEG/sodium citrate (PEG/NaCit) aqueous two-phase systems. The presence of PEGs of different molar masses slightly altered the native structure of xylanase, although its catalytic activity was not affected. All the polymers assayed protect the native structure (and catalytic activity) of xylanase against temperature, except for PEG1000. Surface hydrophobicity experiments showed that xylanase favorable interacts with PEGs. Partitioning experiments confirmed this result and demonstrated that PEG1000/NaCit is the best system to partition xylanase from Thermomyces lanuginosus, since the Kp was 17.7 ± 0.3.


Assuntos
Ascomicetos/enzimologia , Citratos/química , Endo-1,4-beta-Xilanases , Proteínas Fúngicas , Polietilenoglicóis/química , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Polietilenoglicóis/análise , Citrato de Sódio
7.
J Chromatogr A ; 1428: 246-54, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26381570

RESUMO

This paper summarises results of zinc content and its speciation in human milk from mothers of preterm and full-term infants at different stages of lactation and from synthetic formula milks. Human milk samples (colostrum, 7th, 14th, and 28th day after delivery) from Spanish and Brazilian mothers of preterm and full-term infants (and also formula milks) were collected. After adequate treatment of the sample, total Zn was determined, while speciation analysis of the Zn was accomplished by size exclusion chromatography coupled online with the ICP-MS. It is observed that total zinc content in human milk decreases continuously during the first month of lactation, both for preterm and full term gestations. All infant formulas analysed for total Zn were within the currently legislated levels. For Zn speciation analysis, there were no differences between preterm and full term human milk samples. Moreover Zn species elute mainly associated with immunoglobulins and citrate in human milk whey. Interestingly the speciation in formula milk whey turned out to be completely different as the observed Zn(2+) was bound almost exclusively to low molecular weight ligands (citrate) and only comparatively very low amounts of the metal appeared to be associated with higher mass biomolecules (e.g. proteins).


Assuntos
Cromatografia em Gel , Análise de Alimentos/métodos , Fórmulas Infantis/química , Espectrometria de Massas , Leite Humano/química , Zinco/análise , Brasil , Citratos/química , Humanos , Lactente , Peso Molecular
8.
Protein Expr Purif ; 106: 66-71, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25448594

RESUMO

Enzyme extraction using aqueous two-phase systems (ATPS) has been increasingly used as a primary recovery technique which integrates the clarification, concentration and partial purification of important biomolecules from their natural source in a single step. The goal of this work was to optimize the extraction of trypsin from pancreas homogenate with polyethylene glycol and sodium citrate (PEG/NaCit) ATPS by using the tools of experimental design. The variables NaCl concentration - added inert salt -, the top/bottom phase volume ratio - Vr - and the biomass loaded into the system - in percentage - were selected as the main factors in the trypsin extraction. The yield (%) and the purification factor of trypsin were considered the responses to be optimized. The central composite design and the response surface analysis proved to be suitable tools for a quick and efficient study. As a result, the optimal extraction conditions in PEG3350/NaCit system were 3.34% wt/wt for NaCl concentration, a biomass load which represented 9.30% wt/wt of the total ATPS mass and 6.37 top/bottom volume ratio giving a purification factor of 2.55 and a yield of 99.7% in top phase.


Assuntos
Bioquímica/métodos , Citratos/química , Pâncreas/enzimologia , Polietilenoglicóis/química , Tripsina/isolamento & purificação , Animais , Bovinos , Concentração de Íons de Hidrogênio , Extratos Pancreáticos/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes , Citrato de Sódio , Água
9.
Environ Sci Pollut Res Int ; 21(12): 7548-56, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24595755

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous compounds with carcinogenic and/or mutagenic potential. To address the limitations of individual remediation techniques and to achieve better PAH removal efficiencies, the combination of chemical and biological treatments can be used. The degradation of phenanthrene (chosen as a model of PAH) by persulfate in freshly contaminated soil microcosms was studied to assess its impact on the biodegradation process and on soil properties. Soil microcosms contaminated with 140 mg/kgDRY SOIL of phenanthrene were treated with different persulfate (PS) concentrations 0.86-41.7 g/kgDRY SOIL and incubated for 28 days. Analyses of phenanthrene and persulfate concentrations and soil pH were performed. Cultivable heterotrophic bacterial count was carried out after 28 days of treatment. Genetic diversity analysis of the soil microcosm bacterial community was performed by PCR amplification of bacterial 16S rDNA fragments followed by denaturing gradient gel electrophoresis (DGGE). The addition of PS in low concentrations could be an interesting biostimulatory strategy that managed to shorten the lag phase of the phenanthrene biological elimination, without negative effects on the physicochemical and biological soil properties, improving the remediation treatment.


Assuntos
Biodegradação Ambiental , Fenantrenos/química , Microbiologia do Solo , Poluentes do Solo/química , Argentina , Citratos/química , DNA Ribossômico/análise , Eletroforese em Gel de Gradiente Desnaturante , Concentração de Íons de Hidrogênio , Oxirredução , Fenantrenos/análise , Reação em Cadeia da Polimerase , Citrato de Sódio , Compostos de Sódio/química , Poluentes do Solo/análise , Sulfatos/química
10.
PLoS One ; 9(2): e88234, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24551084

RESUMO

The potential use of natural cyclodextrins and their synthetic derivatives have been studied extensively in pharmaceutical research and development to modify certain properties of hydrophobic drugs. The ability of these host molecules of including guest molecules within their cavities improves notably the physicochemical properties of poorly soluble drugs, such as albendazole, the first chosen drug to treat gastrointestinal helminthic infections. Thus, the aim of this work was to synthesize a beta cyclodextrin citrate derivative, to analyze its ability to form complexes with albendazole and to evaluate its solubility and dissolution rate. The synthesis progress of the cyclodextrin derivative was followed by electrospray mass spectrometry and the acid-base titration of the product. The derivative exhibited an important drug affinity. Nuclear magnetic resonance experiments demonstrated that the tail and the aromatic ring of the drug were inside the cavity of the cyclodextrin derivative. The inclusion complex was prepared by spray drying and full characterized. The drug dissolution rate displayed exceptional results, achieving 100% drug release after 20 minutes. The studies indicated that the inclusion complex with the cyclodextrin derivative improved remarkably the physicochemical properties of albendazole, being a suitable excipient to design oral dosage forms.


Assuntos
Albendazol/química , Fenômenos Químicos , Citratos/química , beta-Ciclodextrinas/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Transição de Fase , Solubilidade , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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