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1.
Nanomaterials (Basel) ; 10(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33260887

RESUMO

Two series of new photocatalysts were synthesized based on modification with Pd of the commercial P25 photocatalyst (EVONIK®). Two techniques were employed to incorporate Pd nanoparticles on the P25 surface: photodeposition (series Pd-P) and impregnation (series Pd-I). Both series were characterized in depth using a variety of instrumental techniques: BET, DRS, XRD, XPS, TEM, FTIR and FESEM. The modified series exhibited a significant change in pore size distribution, but no differences compared to the original P25 with respect to crystalline phase ratio or particle size were observed. The Pd0 oxidation state was predominant in the Pd-P series, while the presence of the Pd2+ oxidation state was additionally observed in the Pd-I series. The photoactivity tests were performed in a continuous photoreactor with the photocatalysts deposited, by dip-coating, on borosilicate glass plates. A total of 500 ppb of NO was used as input flow at a volumetric flow rate of 1.2 L·min-1, and different relative humidities from 0 to 65% were tested. The results obtained show that under UV-vis or Vis radiation, the presence of Pd nanoparticles favors NO removal independently of the Pd incorporation method employed and independently of the tested relative humidity conditions. This improvement seems to be related to the different interaction of the water with the surface of the photocatalysts in the presence or absence of Pd. It was found in the catalyst without Pd that disproportionation of NO2 is favored through its reaction with water, with faster surface saturation. In contrast, in the catalysts with Pd, disproportionation took place through nitro-chelates and adsorbed NO2 formed from the photocatalytic oxidation of the NO. This different mechanism explains the greater efficiency in NOx removal in the catalysts with Pd. Comparing the two series of catalysts with Pd, Pd-P and Pd-I, greater activity of the Pd-P series was observed under both UV-vis and Vis radiation. It was shown that the Pd0 oxidation state is responsible for this greater activity as the Pd-I series improves its activity in successive cycles due to a reduction in Pd2+ species during the photoactivity tests.

2.
J Biomol Struct Dyn ; 37(12): 3259-3268, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30088792

RESUMO

The fucosterol has been reported numerous biological activities. In this study, the activity in vitro of the fucosterol from Sargassum horridum as potential human acetylcholinesterase inhibitor was evaluated. The structural identification was obtained by nuclear magnetic resonance (NMR) spectroscopy and based on experimental data, we combined docking and molecular dynamics simulations coupled to the molecular-mechanics-generalized-born-surface-area approach to evaluating the structural and energetic basis for the molecular recognition of fucosterol and neostigmine at the binding site of acetylcholinesterase (AChE). In addition, the Lineweaver-Burk plot showed the nature of a non-competitive inhibition. The maximum velocity (Vmax) and the constant of Michaelis-Menten (Km) estimated for fucosterol (0.006 µM) were 0.015 1/Vo (ΔA/h and 6.399 1/[ACh] mM-1, respectively. While, for neostigmine (0.14 µM), the Vmax was 0.022 1/Vo (ΔA/h) and Km of 6.726 1/[ACh] mM-1, these results showed a more effective inhibition by fucosterol respect to neostigmine. Structural analysis revealed that neostigmine reaches the AChE binding site reported elsewhere, whereas fucosterol can act as a no-competitive and competitive acetylcholinesterase inhibitor, in agree with kinetic enzymatic experiments. Binding free energy calculations revealed that fucosterol reaches the acetylcholinesterase binding site with higher affinity than neostigmine, which is according to experimental results. Whereas the per-residue decomposition free energy analysis let us identify crucial residues involved in the molecular recognition of ligands by AChE. Results corroborate the ability of theoretical methods to provide crucial information at the atomic level about energetic and structural differences in the binding interaction and affinity from fucosterol with AChE. Communicated by Ramaswamy H. Sarma.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Sargassum/química , Estigmasterol/análogos & derivados , Sítios de Ligação/efeitos dos fármacos , Humanos , Cinética , Ligantes , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Estigmasterol/farmacologia
3.
Opt Express ; 25(22): 27845-27856, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092254

RESUMO

The thermal sensing capability of the Tm3+-doped yttrium orthoaluminate nanoperovskite in the infrared range, synthetized by a sol-gel method, was studied. The temperature dependence of the infrared upconverted emission bands located at around 705 nm (3F2,3→3H6) and 800 nm (3H4→3H6) of YAP: Tm3+ nanoperovskite under excitation at 1210 nm was analyzed from RT up to 425 K. Calibration of the optical sensor has been made using the fluorescence intensity ratio technique, showing a high sensitivity in the near-infrared compared to other trivalent rare-earth based optical sensors working in the same range. In addition, a second calibration procedure of the YAP: Tm3+ optical sensor was performed by using the FIR technique on the emission band associated to the 3H4→3H6 transition in the physiological temperature range (293-333 K), showing a very high relative sensitivity compared with other rare-earth based optical temperature sensors working in the physiological range. Moreover, the main advantage compared with other optical sensors is that the excitation source and the upconverted emissions do not overlap, since they lie in different biological windows, thus allowing its potential use as an optical temperature probe in the near-infrared range for biological applications.

5.
Chem Biol Interact ; 209: 1-13, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24321698

RESUMO

A set of 84 known N-aryl-monosubstituted derivatives (42 amides: series 1 and 2, and 42 imides: series 3 an 4, from maleic and succinic anhydrides, respectively) that display inhibitory activity toward both acetylcholinesterase and butyrylcholinesterase (ChEs) was considered for Quantitative structure-activity relationship (QSAR) studies. These QSAR studies employed docking data from both ChEs that were previously submitted to molecular dynamics (MD) simulations. Donepezil and galanthamine stereoisomers were included to analyze their quantum mechanics properties and for validating the docking procedure. Quantum parameters such as frontier orbital energies, dipole moment, molecular volume, atomic charges, bond length and reactivity parameters were measured, as well as partition coefficients, molar refractivity and polarizability were also analyzed. In order to evaluate the obtained equations, four compounds: 1a (4-oxo-4-(phenylamino)butanoic acid), 2a ((2Z)-4-oxo-4-(phenylamino)but-2-enoic acid), 3a (2-phenylcyclopentane-1,3-dione) and 4a (2-phenylcyclopent-4-ene-1,3-dione) were employed as independent data set, using only equations with r(m(test))²>0.5. It was observed that residual values gave low value in almost all series, excepting in series 1 for compounds 3a and 4a, and in series 4 for compounds 1a, 2a and 3a, giving a low value for 4a. Consequently, equations seems to be specific according to the structure of the evaluated compound, that means, series 1 fits better for compound 1a, series 3 or 4 fits better for compounds 3a or 4a. Same behavior was observed in the butyrylcholinesterase (BChE). Therefore, obtained equations in this QSAR study could be employed to calculate the inhibition constant (Ki) value for compounds having a similar structure as N-aryl derivatives described here. The QSAR study showed that bond lengths, molecular electrostatic potential and frontier orbital energies are important in both ChE targets. Docking studies revealed that despite the multiple conformations obtained through MD simulations on both ChEs, the ligand recognition properties were conserved. In fact, the complex formed between ChEs and the best N-aryl compound reproduced the binding mode experimentally reported, where the ligand was coupled into the choline-binding site and stabilized through π-π interactions with Trp82 or Trp86 for BChE and AChE, respectively, suggesting that this compound could be an efficient inhibitor and supporting our model.


Assuntos
Colinesterases/química , Simulação de Dinâmica Molecular , Sítios de Ligação , Butirilcolinesterase/química , Colinesterases/efeitos dos fármacos , Donepezila , Sistemas de Liberação de Medicamentos , Galantamina/química , Galantamina/farmacologia , Indanos/química , Indanos/farmacologia , Modelos Moleculares , Estrutura Molecular , Piperidinas/química , Piperidinas/farmacologia , Relação Quantitativa Estrutura-Atividade
6.
Int. j. morphol ; 31(4): 1459-1469, Dec. 2013. ilus
Artigo em Inglês | LILACS | ID: lil-702334

RESUMO

This study described the reproductive system and gonadal development of Octopus rubescens from Bahía de Todos Santos, Baja California, Mexico. A total of 65 organisms, 35 males weighing 7.2 to 543.4 g and 30 females from 9.4 to 87.7 g where analyzed. The gonad development was defined through histological methods using Hematoxylin-eosin and Arteta- trichrome stains. We describe macroscopically the reproductive system of males and females, and characterized each of the anatomic components. Eight stages of maturity were recognized in females: 1. Immature, 2. Initial folliculogenesis, 3. Final folliculogenesis, 4. Previtelogenesis, 5. Early vitelogenesis, 6. Final vitelogenesis, 7. Maturing and 8. Spawn. In males five stages were identified: 1. Immature, 2. Maturing A, 3. Maturing B, 4. Mature type 1 and 5. Mature type 2. This work is the first histological description of the reproductive system of this species and the beginning for future research on its basic biology.


En el presente estudio se describió el aparato reproductor y el desarrollo gonadal del pulpo Octopus rubescens de la Bahía de Todos Santos en Baja California, México. Se realizó la descripción macroscópica del aparato reproductor de hembras y machos y se caracterizó cada una de las partes que lo integran. Para la descripción del desarrollo gonadal se utilizaron las técnicas histológicas de Hematoxilina-Eosina y la tinción tricrómica de Arteta. Se analizaron histológicamente un total de 65 organismos de los cuales 35 machos tuvieron un intervalo de peso de 7,2 a 543,4 g y las 30 hembras de 9,4 a 87,7 g. La escala de madurez en las hembras se caracterizó con ocho estadios: 1. Inmaduro, 2. Foliculogénesis inicial, 3. Foliculogénesis final, 4. Previtelogénesis, 5. Vitelogénesis inicial, 6. Vitelogénesis final, 7. Maduros y 8. Desovados. En los machos se identificaron cinco estadios: 1. Inmaduro, 2. En maduración A, 3. En maduración B, 4. Maduro tipo 1 y 5. Maduro tipo 2. Este trabajo constituye la primera descripción histológica del aparato reproductor de esta especie y sienta las bases para futuras investigaciones sobre su biología básica.


Assuntos
Masculino , Animais , Feminino , Genitália/anatomia & histologia , Octopodiformes/anatomia & histologia , Gônadas/anatomia & histologia
8.
Vet Parasitol ; 186(3-4): 254-60, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22130333

RESUMO

Ehrlichiosis and babesiosis are tick-borne diseases, caused mainly by Ehrlichia canis and Babesia canis, respectively, with a worldwide occurrence in dogs, whose main vector is the brown-dog tick, Rhipicephalus sanguineus. The present work aimed to detect the presence of E. canis and Babesia sp. in 91 dog blood samples in Colombia, by molecular and serological techniques. We also performed sequence alignment to indicate the identity of the parasite species infecting these animals. The present work shows the first molecular detection of E. canis and B. vogeli in dogs from Colombia. Immunoglobulin-G (IgG) antibodies to E. canis and Babesia vogeli were found in 75 (82.4%) and 47 (51.6%) sampled dogs, respectively. Thirty-seven (40.6%) and 5 (5.5%) dogs were positive in PCR for E. canis and Babesia sp., respectively. After sequencing, amplicons showed 99% of identity with isolates of E. canis and B. vogeli. The phylogenetic trees based on 16S rRNA-Anaplasmataceae sequences and 18S rRNA-piroplasmid sequences supported the identity of the found E. canis and B. vogeli DNAs, respectively. The present work shows the first molecular detection of E. canis and B. vogeli in dogs in Colombia.


Assuntos
Babesia/isolamento & purificação , Babesiose/veterinária , Doenças do Cão/diagnóstico , Ehrlichia canis/isolamento & purificação , Ehrlichiose/veterinária , Animais , Babesia/genética , Babesiose/sangue , Babesiose/epidemiologia , Colômbia/epidemiologia , Doenças do Cão/sangue , Doenças do Cão/epidemiologia , Cães , Ehrlichia canis/genética , Ehrlichiose/sangue , Ehrlichiose/epidemiologia , Filogenia , Estudos Soroepidemiológicos
9.
Rev. esp. pediatr. (Ed. impr.) ; 66(6): 327-327, nov.-dic. 2010.
Artigo em Espanhol | IBECS | ID: ibc-92166
10.
J Mech Behav Biomed Mater ; 3(8): 619-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20826368

RESUMO

This work presents an analysis of a total hip prosthesis that failed in service prematurely within 5 years. The prosthesis presented a fractured stem that was extracted from a 46 year old male patient, 75 kg weight and 1.76 m height. In order to determine the origin of the failure, the femoral stem component was analyzed by means of visual inspection; optical microscope (OM), scanning electronic microscopy (SEM) and energy disperse spectroscopy (EDS). The investigation showed that the crack had originated due to a high stress concentration on the anterolateral corner section of the stem. Any discontinuity or defect on the prosthesis surface in this location acted as preferential site to nucleate a crack which propagated by fatigue until the cross section was not able to sustain an eventual high load produced for the active patient.


Assuntos
Prótese de Quadril , Falha de Prótese , Artroplastia de Quadril , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Futebol
11.
Comp Biochem Physiol A Mol Integr Physiol ; 147(3): 703-710, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16935535

RESUMO

Fatty acid composition of cellular membranes can modify permeability and can modulate the activity of Na(+)/K(+)-ATPase. Although highly unsaturated fatty acids (HUFA) improve survival and osmoregulatory capacity to low salinities in penaeid shrimp, the possible mechanisms have not been established. For this purpose the influence of HUFA supplementation in diet (2.9 vs. 34% HUFA proportion to total fatty acids) on osmoregulatory responses of juvenile Litopenaeus vannamei submitted to an acute (15 h) or chronic exposure (21 days), to low (5 g L(-1)) and high salinities (50 g L(-1)) was analyzed. Shrimp fed the high-HUFA diet, had higher concentration of main HUFA (20:5n-3 and 22:6n-3) in polar lipids of gills. Osmotic pressure in hemolymph was significantly affected by salinity in acute (640, 751, 847 mOsm/kg for 5, 30 and 50 g L(-1), respectively), and chronic exposure (645, 713, 814 mOsm/kg), but variations between them were small compared to environmental salinity (206, 832, 1547 mOsm/kg), indicating that osmoregulation was achieved in a matter of hours. An increase in Na(+)/K(+)-ATPase activity was observed only after a chronic exposure to low salinity. Free amino acids (FAA), mainly alanine and arginine, were higher at 30 (control) and 50 g L(-1) in accordance to their role as organic osmolites. Neither osmotic pressure, Na(+)/K(+)-ATPase activity, nor FAA was affected by HUFA supplementation. However, higher water content in gills of shrimp exposed to low salinities was counteracted by increased HUFA content, which could be a result of changes in water permeability of gills. The osmoregulatory capacity of penaeid shrimp to low and high salinities was achieved within 15 h of acclimation and did not depend on HUFA supplementation in the diet.


Assuntos
Dieta , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos Insaturados/farmacologia , Penaeidae/efeitos dos fármacos , Penaeidae/enzimologia , Cloreto de Sódio/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Aminoácidos/análise , Animais , Brânquias/química , Brânquias/efeitos dos fármacos , Hemolinfa/química , Hemolinfa/efeitos dos fármacos , Músculos/química , Músculos/efeitos dos fármacos , Concentração Osmolar , Proteínas/análise , Água/metabolismo
12.
Rev. esp. pediatr. (Ed. impr.) ; 62(6): 466-472, nov.-dic. 2006. tab
Artigo em Espanhol | IBECS | ID: ibc-114299

RESUMO

En los últimos años se ha incrementado el uso de los productos de soja en la alimentación infantil en los países occidentales. Esto constituye una aportación dietética útil en algunas circunstancias pero en otras ocasiones pueden no estar indicados. En esta puesta al día se revisan las características de la soja, las acciones fisiopatológicas de sus componentes y las principales indicaciones en el niño y adolescente: alergia a la leche de vaca, intolerancia a la lactosa, galactosemia, regímenes vegetarianos y otras dietas no convencionales, anorexia nerviosa y obesidad. De acuerdo con las normas de los más importantes organismos internacionales, se precisan las condiciones de utilización en algunos de estos procesos y las limitaciones de su uso en el recién nacido y en el lactante (AU)


In recent years, the use of soy products in baby food in Western countries has increased. This is a useful dietary supply in some circumstances, but in others, it is possible that it may not be indicated. In this update, a review is made of the characteristics of soy, the pathophysiological actions of its components and the principal indications in the child and adolescent: allergy to cow milk, lactose intolerance, galactosemia, vegetarian diets and other nonconventional diets, anorexia nervosa and obesity. In accordance with the guidelines o the most important international organizations, the conditions for its use in some of these conditions and limitations of its use in the newborn and infant are explained (AU)


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Alimentos Infantis/análise , Transtornos da Nutrição do Lactente/dietoterapia , Alimentos Formulados/análise , Alimentos de Soja , Soja/metabolismo
16.
An Esp Pediatr ; 51(2): 154-8, 1999 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-10495502

RESUMO

OBJECTIVE: The purpose of this study was to determine the incidence rate and the relative frequency of epilepsy and epileptic syndromes during childhood in the province of Albacete. PATIENTS AND METHODS: Patients with childhood epilepsy living in the area have been diagnosed in the Neuropediatric Unit at the General Hospital of Albacete. We included patients under 11 years of age with unprovoked recurring epileptic seizures whose first seizure happened between 1-1-1987 and 1-12-1991, excluding those who have only suffered from febrile seizures and other provoked epileptic seizures. RESULTS: In the five-year period of the study, 136 patients from a population of 60,000 children under 11 years of age suffered from epilepsy. The annual incidence rate of epilepsy at this age is 45 in 100,000. For those under 1 year it is 113, for those aged 1 to 5 it is 52, and for those between 6 and 10 years 30. The most common epileptic syndrome is benign childhood epilepsy with centrotemporal spikes (29%), followed by undefined generalized idiopathic epilepsy (16%), symptomatic partial epilepsy (15%) and childhood absence epilepsy (9%). CONCLUSIONS: The epilepsy incidence rates reported here are lower than those found in most studies. Nevertheless, these results agree with some more recent studies. Benign childhood epilepsy with centrotemporal spikes is the most frequent epileptic syndrome during childhood.


Assuntos
Epilepsia/epidemiologia , Distribuição por Idade , Área Programática de Saúde , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , Estudos Prospectivos , Espanha/epidemiologia , Síndrome
17.
An Esp Pediatr ; 45(4): 386-92, 1996 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-9005726

RESUMO

A retrospective study was performed on children with hypercholesterolemia or hypertriglyceridemia referred to the Endocrine Clinic of the Niño Jesús University Hospital over a period of 5 years. One hundred twenty-seven children, from 2 to 16 years of age, were followed. The subjects were classified into the following groups: 90 with primary hyperlipidemia [55 polygenic hypercholesterolemia (PH), 23 familial hypercholesterolemia (FH) and 12 with familial combined hyperlipidemia (FCH)]; 2 with secondary hypercholesterolemia and 35 were found to have normal cholesterol and triglyceride values. All patients with primary hyperlipoproteinemia were instructed to carry out dietary intervention during a 6 month period, following the step I recommendations of the National Cholesterol Education Program (NCEP). The following results were obtained: In the group of children with PH and FH a decrease in total and LDL cholesterol was observed (p < 0.0001 for both groups). In the group of FH, a decrease in the LDL/HDL ratio was also observed (p < 0.01). In contrast, the group of children with FCH did not show any changes in the lipoprotein pattern after dietary intervention. In the three groups studied, no statistically significant differences were observed in the remaining parameters (HDL-C, VLDL, and apo A1) after dietary intervention. Lp(a) levels above 30 mg/dl were observed in 25%, 37% and 46% of the children with PH, FH and FCH, respectively. Nine patients with FH were treated with resins for 3 months. In these children a decrease in total and LDL cholesterol, apo B and in the LDL/HDL ratio was observed (p < 0.05). No changes in Lp(a) and HDL-C were observed in this group of children. In our experience, dietary intervention to reduce fat and cholesterol intake in children with primary hyperlipoproteinemia, a population at high risk of developing atherosclerosis, is safe and useful. The treatment with resins in children with FH improves their lipoprotein profile.


Assuntos
Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/terapia , Adolescente , Criança , Pré-Escolar , Dietoterapia , Feminino , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino
20.
Rev. Finlay ; 5(3): 287-93, 1991. tab
Artigo em Espanhol | LILACS | ID: lil-267434

RESUMO

Se hace un estudio de 56 pacientes escogidos al azar simple de un universo de 112 pacientes que asisten a la consulta de reumatología del Hospital Provincial Clínico Quirúrgico Docente Dr. Gustavo Aldereguía Lima, afectados de artritis rematoidea, a los que se les realizó pruebas funcionales respiratorias, se consideró la edad, sexo y tiempo de evolución de la enfermedad. Predominó el sexo femenino y el grupo etareo de 45 a 59 años. Todos los parámetros ventilatorios investigados mostraron diferentes alteraciones, pero el mas afectado fue la capacidad vital, también se mostraron mas alterados, mientras mas años de evolución presentó la enfermedad y las pruebas funcionales respiratorias normales predominaron en los pacientes con menos de 2 años de evolución de la artritis reumatoidea


Assuntos
Artrite Reumatoide/complicações , Pneumopatias/etiologia
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