Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Andes Pediatr ; 94(3): 278-285, 2023 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-37909930

RESUMO

Insulin therapy is complex in pediatric patients because they present greater variations in insulin requirements. Traditional insulins have limitations related to time of onset of action and duration of effect, which has led to the development of new insulins, seeking to reduce chronic complications, severe or nocturnal hypoglycemia, and to improve adherence to therapy. This review updates the information on new insulins, their mechanisms of action and the benefits they provide in the treatment of diabetes. Insulin analogues attempt to mimic the physiological secretion of the hormone, including time of action and duration of effect. The most used prandial analogs are the so-called rapid-acting insulins, including Faster Aspartic and the new basal insulins, glargine U300 and degludec, which have a prolonged action of more than 24 hours and therefore require a daily dose. New technologies under development include biosimilar insulins such as the glargine biosimilar, already available in the clinic. New formulations are being developed for the future, as well as novel ways of dispersing them, mimicking the action of pancreatic cells, which will allow a more physiological and personalized management of the disease.


Assuntos
Medicamentos Biossimilares , Diabetes Mellitus Tipo 1 , Insulinas , Humanos , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina Glargina/uso terapêutico , Insulina/uso terapêutico
2.
Food Chem ; 268: 264-270, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30064756

RESUMO

The aim of this study was to determine the insecticide residue processing factor (PF) from plums to prunes and the effect of the industrial processing of prunes residue concentrations. Our results show an increase of insecticide concentrations during plum dehydration that is explained by fruit water loss; however, the normalized insecticide residue concentration, based on plum dry weights to compensate dehydration, was reduced. The water washing and tenderizing of prunes produced insecticide residue reductions of 22.9 ±â€¯4.5% and 21.9 ±â€¯4.2%, respectively. PF were: 1.157, 1.872, 1.316, 0.192, 2.198, 0.775 and 0.156 for buprofezin, l-cyhalothrin, spirodiclofen, indoxacarb, acetamiprid, imidacloprid and emamectin benzoate, respectively, being directly related to water solubility, aqueous hydrolysis and degradation point and inversely related to molecular mass and melting point. In plums for the dehydrated agroindustry the final product is prunes, therefore, it is crucial to consider the PF to determine the specific preharvest interval for this important agroindustry.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Prunus domestica/química , Frutas/química , Frutas/metabolismo , Ivermectina/análogos & derivados , Ivermectina/análise , Ivermectina/química , Ivermectina/isolamento & purificação , Neonicotinoides/análise , Neonicotinoides/química , Neonicotinoides/isolamento & purificação , Nitrilas/análise , Nitrilas/química , Nitrilas/isolamento & purificação , Nitrocompostos/análise , Nitrocompostos/química , Nitrocompostos/isolamento & purificação , Oxazinas/análise , Oxazinas/química , Oxazinas/isolamento & purificação , Oxirredução , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Prunus domestica/metabolismo , Piretrinas/análise , Piretrinas/química , Piretrinas/isolamento & purificação , Extração em Fase Sólida
3.
Food Chem ; 221: 548-554, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979240

RESUMO

The aim of this study was to evaluate the effect of pesticide formulations and fruit growth stages on the Pre-harvest Interval Period (PHI). Results showed that pesticide formulations did not affect the initial deposit and dissipation rate. However, the fruit growth stage at the application time showed a significant effect on the above-mentioned parameters. Fruit diameter increases in one millimeter pesticide dissipation rates were reduced in -0.033mgkg-1day-1 (R2=0.87; p<0.001) for grapes and -0.014mgkg-1day-1 (R2=0.85; p<0.001) for apples. The relation between solar radiation, air humidity and temperature, and pesticide dissipation rates were dependent on fruit type. PHI could change according to the application time, because of the initial amount of pesticide deposit in the fruits and change in the dissipation rates. Because Maximum Residue Level are becoming more restrictive, it is more important to consider the fruit growth stage effects on pesticide when performing dissipation studies to define PHI.


Assuntos
Contaminação de Alimentos/análise , Malus/efeitos dos fármacos , Malus/crescimento & desenvolvimento , Praguicidas/análise , Vitis/efeitos dos fármacos , Vitis/crescimento & desenvolvimento , Composição de Medicamentos , Frutas/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Resíduos de Praguicidas/análise , Praguicidas/farmacologia
4.
J Environ Sci Health B ; 46(1): 62-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21191865

RESUMO

This investigation was performed to determine the effect of physicochemical soil properties on penoxsulam, molinate, bentazon, and MCPA adsorption-desorption processes. Four soils from Melozal (35° 43' S; 71° 41' W), Parral (36° 08' S; 71° 52' W), San Carlos (36° 24' S; 71° 57' W), and Panimavida (35° 44' S; 71° 24' W) were utilized. Herbicide adsorption reached equilibrium after 4 h in all soils. The Freundlich L-type isotherm described the adsorption process, which showed a high affinity between herbicides and sorption sites mainly because of hydrophobic and H-bonds interaction. Penoxsulam showed the highest adsorption coefficients (4.23 ± 0.72 to 10.69 ± 1.58 mL g⁻¹) and were related to soil pH. Molinate showed K(d) values between 1.72 ± 0.01 and 2.3 ± 0.01 mL g⁻¹ and were related to soil pH and organic matter, specifically to the amount of humic substances. Bentazon had a high relationship with pH and humic substances and its K(d) values were the lowest, ranging from 0.11 ± 0.01 to 0.42 ± 0.01 mL g⁻¹. MCPA K(d) ranged from 0.14 ± 0.02 to 2.72 ± 0.01 mL g⁻¹, however its adsorption was related to humic acids and clay content. According to these results, the soil factors that could explain the sorption process of the studied herbicides under paddy rice soil conditions, were principally humic substances and soil pH. Considering the sorption variability observed in this study and the potential risk for groundwater contamination, it is necessary to develop weed rice management strategies that limit use of herbicides that exhibit low soil adsorption in areas with predisposing conditions to soil leaching.


Assuntos
Herbicidas/química , Oryza , Poluentes do Solo/química , Absorção , Adsorção , Agricultura , Brasil , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Solo/química , Poluentes Químicos da Água/química
5.
J Food Sci ; 75(6): H172-81, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20722929

RESUMO

Apple peel is a waste product from dried apple manufacture. The content of phenolic compounds, dietary fiber, and mineral are higher in apple peel, compared to other edible parts of this fruits. The objective of this study was to develop an ingredient from Granny Smith apple peel, using a pilot scale double drum-dryer, as drying technology. The control of all steps to maximize the retention of phenolic compounds and dietary fiber was considered. Operational conditions, such as drying temperature and time were determined, as well as important preprocessing steps like grinding and PPO inhibition. In addition, the physical-chemical characteristics, mineral and sugar content, and technological functional properties such as water retention capacity, solubility index, and dispersability among others, were analyzed. A simple, economical, and suitable pilot scale process, to produce a powder ingredient from apple peel by-product, was obtained. The drying process includes the application of ascorbic acid at 0.5% in the fresh apple peel slurry, drum-dryer operational conditions were 110 degrees C, 0.15 rpm and 0.2 mm drum clearance. The ingredient developed could be considered as a source of phenolic compounds (38.6 mg gallic acid equivalent/g dry base) and dietary fiber (39.7% dry base) in the formulation of foods. Practical Application: A method to develop an ingredient from Granny Smith apple peel using a pilot scale double drum-dryer as drying technology was developed. The method is simple, economical, feasible, and suitable and maximizes the retention of phenolic compounds and dietary fiber present in the raw matter. The ingredient could be used in the formulation of foods.


Assuntos
Fibras na Dieta/análise , Flavonoides/análise , Alimentos Fortificados , Frutas/química , Malus/química , Fenóis/análise , Antioxidantes/administração & dosagem , Ácido Ascórbico/química , Catecol Oxidase/antagonistas & inibidores , Catecol Oxidase/metabolismo , Fenômenos Químicos , Fibras na Dieta/administração & dosagem , Inibidores Enzimáticos/química , Flavonoides/administração & dosagem , Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Indústria de Processamento de Alimentos/economia , Temperatura Alta , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Resíduos Industriais/economia , Fenóis/administração & dosagem , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/metabolismo , Polifenóis , Solubilidade , Fatores de Tempo , Oligoelementos/administração & dosagem , Oligoelementos/análise , Água/análise
6.
Res Microbiol ; 160(2): 125-33, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19154787

RESUMO

The Geobacillus stearothermophilus V cobA gene encoding uroporphyrinogen-III C-methyltransferase (also referred to as SUMT) was cloned into Escherichia coli and the recombinant enzyme was overexpressed and purified to homogeneity. The enzyme binds S-adenosyl-L-methionine and catalyzes the production of III methyl uroporphyrinogen in vitro. E. coli cells expressing the G. stearothermophilus V cobA gene exhibited increased resistance to potassium tellurite and potassium tellurate. Site-directed mutagenesis of cobA abolished tellurite resistance of the mesophilic, heterologous host and SUMT activity in vitro. No methylated, volatile derivatives of tellurium were found in the headspace of tellurite-exposed cobA-expressing E. coli, suggesting that the role of SUMT methyltransferase in tellurite(ate) detoxification is not related to tellurium volatilization.


Assuntos
Escherichia coli/metabolismo , Geobacillus stearothermophilus/enzimologia , Metiltransferases , Telúrio/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Metiltransferases/análise , Metiltransferases/biossíntese , Metiltransferases/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/biossíntese , S-Adenosilmetionina/metabolismo , Uroporfirinogênios/biossíntese
7.
J Bacteriol ; 189(24): 8953-60, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17951385

RESUMO

Tellurite exerts a deleterious effect on a number of small molecules containing sulfur moieties that have a recognized role in cellular oxidative stress. Because cysteine is involved in the biosynthesis of glutathione and other sulfur-containing compounds, we investigated the expression of Geobacillus stearothermophilus V cysteine-related genes cobA, cysK, and iscS and Escherichia coli cysteine regulon genes under conditions that included the addition of K2TeO3 to the culture medium. Results showed that cell tolerance to tellurite correlates with the expression level of the cysteine metabolic genes and that these genes are up-regulated when tellurite is present in the growth medium.


Assuntos
Antibacterianos/farmacologia , Bacillaceae/efeitos dos fármacos , Cisteína/genética , Escherichia coli/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Telúrio/farmacologia , Alquil e Aril Transferases/biossíntese , Bacillaceae/genética , Bacillaceae/fisiologia , Proteínas de Bactérias/biossíntese , Liases de Carbono-Enxofre/biossíntese , Cisteína/metabolismo , Cisteína Sintase/biossíntese , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas de Escherichia coli/biossíntese , Regulon
8.
PLoS One ; 1: e70, 2006 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-17183702

RESUMO

Reactive oxygen species damage intracellular targets and are implicated in cancer, genetic disease, mutagenesis, and aging. Catalases are among the key enzymatic defenses against one of the most physiologically abundant reactive oxygen species, hydrogen peroxide. The well-studied, heme-dependent catalases accelerate the rate of the dismutation of peroxide to molecular oxygen and water with near kinetic perfection. Many catalases also bind the cofactors NADPH and NADH tenaciously, but, surprisingly, NAD(P)H is not required for their dismutase activity. Although NAD(P)H protects bovine catalase against oxidative damage by its peroxide substrate, the catalytic role of the nicotinamide cofactor in the function of this enzyme has remained a biochemical mystery to date. Anions formed by heavy metal oxides are among the most highly reactive, natural oxidizing agents. Here, we show that a natural isolate of Staphylococcus epidermidis resistant to tellurite detoxifies this anion thanks to a novel activity of its catalase, and that a subset of both bacterial and mammalian catalases carry out the NAD(P)H-dependent reduction of soluble tellurite ion (TeO(3)(2-)) to the less toxic, insoluble metal, tellurium (Te(o)), in vitro. An Escherichia coli mutant defective in the KatG catalase/peroxidase is sensitive to tellurite, and expression of the S. epidermidis catalase gene in a heterologous E. coli host confers increased resistance to tellurite as well as to hydrogen peroxide in vivo, arguing that S. epidermidis catalase provides a physiological line of defense against both of these strong oxidizing agents. Kinetic studies reveal that bovine catalase reduces tellurite with a low Michaelis-Menten constant, a result suggesting that tellurite is among the natural substrates of this enzyme. The reduction of tellurite by bovine catalase occurs at the expense of producing the highly reactive superoxide radical.


Assuntos
Catalase/metabolismo , Oxirredutases/metabolismo , Sequência de Aminoácidos , Animais , Catalase/genética , Bovinos , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Genes Bacterianos , Técnicas In Vitro , Cinética , Fígado/enzimologia , Mutação , NAD/metabolismo , NADP/metabolismo , Oxirredutases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Staphylococcus epidermidis/enzimologia , Staphylococcus epidermidis/genética , Especificidade por Substrato , Superóxidos/metabolismo , Telúrio/metabolismo , Telúrio/farmacologia
9.
Med. leg. Costa Rica ; 23(2): 111-135, sept. 2006. ilus
Artigo em Espanhol | LILACS | ID: lil-585440

RESUMO

La agresión infantil es un problema social que ha persistido a lo largo de la historia. La problemática abarca lesiones tanto a nivel físico como psicológico. La clínica, en la mayor parte de las veces, es el eje principal en el diagnóstico acertado y el posterior manejo. En este trabajo se analizaron 192 casos de agresión infantil durante el período comprendido entre enero de 2005 y mayo de 2006 y se presentan sus resultados donde la mayoría de los maltratos infantiles incluye abuso sexual, no es común la atención médica luego de la agresión, las víctimas consultan mucho tiempo después y se presentan más casos de maltrato infantil en el mes de Diciembre lo cual podemos asociar con las conductas del mes que suelen ser más irresponsables (fiestas, alcohol, etc.). Es importante que el médico tenga claro los signos de abuso sexual y sus repercusiones tanto físicas como psicológicas ya que es el tipo de agresión más frecuente y muchas veces puede pasar desapercibida.


Child abuse is an issue which has persisted through history. This problem includes not only physical, but psychological damage. Clinical report, most of the times, is the principal axis in the correct diagnosis and the posterior treatment. In this study, 192 cases of child abuse were analyzed between January 2005 and May 2006, and the results presented most of the cases include child molesting, occasional medical attention after the assault, the victims receive medical attention long time after the assault, and most of the cases occur during December, which can be associated with irresponsible behavior (alcohol, parties, etc.). It is very important that the physician is very clear about the signs of sexual abuse and its physical and psychological consequences, since it is the most common type of aggression and in many cases can be unnoticed.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Agressão , Criança , Abuso Sexual na Infância , Defesa da Criança e do Adolescente , Maus-Tratos Infantis/psicologia , Problemas Sociais , Costa Rica
10.
Res Microbiol ; 156(4): 472-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15862444

RESUMO

We have characterized a natural isolate of Staphylococcus epidermidis resistant to heavy metals that carries a small 2391-bp plasmid, pSepCH, encoding the qacC gene. The S. epidermidis qacC gene confers resistance to a number of beta-lactam antibiotics and to ethidium bromide in its natural host and in Escherichia coli K12 and Salmonella enterica sv. Typhimurium. This is the first communication of a small multidrug resistance (SMR) pump involved in resistance to beta-lactam antibiotics. Experiments using tolC, ompW and ompD mutant strains of S. Typhimurium demonstrated that the beta-lactam antibiotic resistance conferred by this pump does not depend on these outer membrane proteins.


Assuntos
Antibacterianos/farmacologia , Antiporters/genética , Proteínas de Membrana/genética , Staphylococcus epidermidis/genética , beta-Lactamas/farmacologia , Antiporters/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli , Etídio/farmacologia , Proteínas de Membrana/metabolismo , Testes de Sensibilidade Microbiana , Plasmídeos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Resistência beta-Lactâmica/genética
11.
Anal Biochem ; 331(1): 106-14, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15246002

RESUMO

Escherichia coli JM109 cells, expressing the genes encoded in a 3.8-kb chromosomal DNA fragment from Geobacillus stearothermophilus V, produced volatile organotellurium compounds which were released into the headspace gas above liquid cultures when amended with tellurite anions in micromolar amounts. Headspace sampling was achieved using gas-syringe extraction or solid-phase microextraction using carboxen-polydimethysiloxane fibers. In addition to dimethyl telluride and dimethyl ditelluride, two new organometalloidal compounds were detected using gas chromatograph with mass spectrometric or fluorine-induced chemiluminescence detection. These compounds are methanetellurol and dimethyl tellurenyl sulfide. The significance of these findings with regard to the current knowledge about bacterial tellurite resistance is discussed.


Assuntos
Cromatografia Gasosa , Escherichia coli K12/química , Genes Bacterianos/genética , Geobacillus stearothermophilus/genética , Compostos Organometálicos/análise , Telúrio/metabolismo , Adaptação Biológica/genética , Escherichia coli K12/genética , Espectrometria de Massas , Compostos Organometálicos/química , Telúrio/farmacologia
12.
J Biol Inorg Chem ; 9(5): 609-15, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15164269

RESUMO

A 3.8-kb fragment of chromosomal DNA of Geobacillus stearothermophilus V cloned in pSP72 (p1VH) confers resistance to potassium tellurite (K(2)TeO(3)) and to potassium tellurate (K(2)TeO(4)) when the encoded genes are expressed in Escherichia coli K-12. The nt sequence of the cloned fragment predicts three ORFs of 780, 399, and 600 bp, whose encoded protein products exhibit about 80% similarity with the SUMT methyltransferase and the BtuR protein of Bacillus megaterium, and with the UbiE methyltransferase of Bacillus anthracis A2012, respectively. In addition, E. coli/p1VH cells evolved dimethyl telluride, which was released into the headspace gas above liquid cultures when amended with K(2)TeO(3) or with K(2)TeO(4). After 48 h of growth in the presence of these compounds, a protein of about 25 kDa was found at a significantly higher level when crude extracts were analyzed by SDS-PAGE. The N-terminal amino acid (aa) sequence of this protein, obtained by Edman degradation, matched the deduced aa sequence predicted by the G. stearothermophilus V ubiE gene. This gene was amplified by PCR, subcloned in pET21b, and transformed into E. coli JM109(DE3). Interestingly, DMTe evolution occurred when these modified cells were grown in K(2)TeO(4) - but not in K(2)TeO(3) - amended media. These results may be indicative that the two Te oxyanions could be detoxified in the cell by different metabolic pathways.


Assuntos
Bacillaceae/química , Proteínas de Bactérias/metabolismo , Escherichia coli K12/efeitos dos fármacos , Telúrio/metabolismo , Telúrio/farmacologia , Ânions/química , Proteínas de Bactérias/genética , Sequência de Bases , Cromossomos/genética , Meios de Cultura , DNA/química , Eletroforese em Gel de Poliacrilamida , Escherichia coli K12/enzimologia , Escherichia coli K12/genética , Dados de Sequência Molecular , Peso Molecular , Telúrio/química , Fatores de Tempo
13.
J Bacteriol ; 185(19): 5831-7, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-13129955

RESUMO

Many eubacteria are resistant to the toxic oxidizing agent potassium tellurite, and tellurite resistance involves diverse biochemical mechanisms. Expression of the iscS gene from Geobacillus stearothermophilus V, which is naturally resistant to tellurite, confers tellurite resistance in Escherichia coli K-12, which is naturally sensitive to tellurite. The G. stearothermophilus iscS gene encodes a cysteine desulfurase. A site-directed mutation in iscS that prevents binding of its pyridoxal phosphate cofactor abolishes both enzyme activity and its ability to confer tellurite resistance in E. coli. Expression of the G. stearothermophilus iscS gene confers tellurite resistance in tellurite-hypersensitive E. coli iscS and sodA sodB mutants (deficient in superoxide dismutase) and complements the auxotrophic requirement of an E. coli iscS mutant for thiamine but not for nicotinic acid. These and other results support the hypothesis that the reduction of tellurite generates superoxide anions and that the primary targets of superoxide damage in E. coli are enzymes with iron-sulfur clusters.


Assuntos
Liases de Carbono-Enxofre , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Geobacillus stearothermophilus/enzimologia , Liases/genética , Telúrio/farmacologia , Escherichia coli/enzimologia , Escherichia coli/genética , Geobacillus stearothermophilus/genética , Liases/isolamento & purificação , Liases/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Análise de Sequência de DNA , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
14.
Curr Microbiol ; 45(3): 187-90, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12177740

RESUMO

Determination of the nucleotide sequence of a 4.5-kb chromosomal DNA fragment of Bacillus stearothermophilus LV revealed two open reading frames (ORFs) of 121 and 727 amino acids (aa) that exhibit a high degree of similarity with the cadC and cadA cadmium resistance genes of a number of microorganisms. Transfer and expression of the B. stearothermophilus LV cadA or cadC/ cadA genes in E. coli caused increased cadmium chloride susceptibility in the bacterial host. Transfer of cadC alone did not result in any detectable phenotypic change in E. coli.


Assuntos
Cádmio/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Geobacillus stearothermophilus/efeitos dos fármacos , Geobacillus stearothermophilus/genética , Adenosina Trifosfatases/genética , Proteínas de Bactérias/genética , Sequência de Bases , Cloreto de Cádmio/farmacologia , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Expressão Gênica , Genes Bacterianos , Fases de Leitura Aberta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...