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1.
Molecules ; 29(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38202668

RESUMO

The leaves of Psidium guajava L. are an agro-industrial by-product with an outstanding content of polyphenolic compounds; however, there are many factors which can affect the phytochemical profile when valuing this type of plant material, such as temperatures and extraction times involving in the extraction methods applied. In this context, this study analyzed the impact of different extraction methods (Soxhlet, maceration and ultrasound-assisted extraction) on the phytochemical profile (FTIR and UPLC-MS) and the antioxidant activity (ABTS, FRAP and Folin-Ciocalteu) of guava leaf extracts. A yield of phenolic compounds per gram of guava leaf was obtained within the range of 16 to 45 mg/g; on the other hand, the IC50 values determined with the ABTS assay ranged between 78 ± 4 to 152 ± 12 µg/mL. The methanolic extract obtained by Soxhlet was the one with the best reducing power, both in the FRAP assay and in the Folin-Ciocalteu assay. Finally, bioactive compounds such as quercetin, kaempferol and avicularin were identified in the guava leaf extract. It was concluded that the purification of polyphenolics compounds improves the antioxidant capacity, and that the extraction method greatly influences the phytochemical profile and activity of the extracts.


Assuntos
Antioxidantes , Benzotiazóis , Psidium , Ácidos Sulfônicos , Antioxidantes/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Compostos Fitoquímicos/farmacologia
2.
Molecules ; 27(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35744863

RESUMO

A comparative study was carried out on the chemical, structural and thermal properties of candelilla wax from four wax-producing communities in Mexico, which was obtained by two extraction processes, the conventional one using sulfuric acid (SA) and an eco-friendly alternative process using citric acid (CA) as the extracting agent. The waxes were analyzed by basic chemistry (acidity, saponification, ester indexes, and others), color, Fourier transform infrared spectroscopy (FTIR), Raman micro-spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and hardness and brittleness measurements. The waxes obtained by the environmentally friendly process showed differences in their physicochemical properties when compared to waxes from the conventional process. In addition, they showed some improvements, such as lighter shades and harder waxes, suggesting that the new environmentally friendly process is a viable option.


Assuntos
Ésteres , Ceras , Varredura Diferencial de Calorimetria , Espectroscopia de Infravermelho com Transformada de Fourier , Ceras/química
3.
Rev. cuba. oftalmol ; 34(3): e974, 2021. graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1352034

RESUMO

El implante de una lente intraocular fáquica puede resultar una opción lógica para los pacientes sumamente miopes que buscan liberarse de las gafas y de los lentes de contacto. Esta es una alternativa para corregir los grados de miopía extremos, y se diseñaron para permanecer dentro del ojo por muchos años. Con el cursar del tiempo, fisiológicamente comienza a opacarse el cristalino. Ante la necesidad de removerlo y de calcular una lente de potencia adecuada para el saco capsular y así conseguir la emetropía, surge un nuevo reto. El cálculo inexacto de la potencia dióptrica de la lente a implantar en la intervención quirúrgica es un problema y con él aparece la sorpresa refractiva; de ahí el objetivo de presentar con este caso la causa más frecuente de sorpresa refractiva tras la cirugía de catarata en un paciente miope con lente fáquica implantada. Se destaca la importancia de la longitud axil, sobre todo si esta se modifica después del implante de la lente fáquica para el correcto cálculo de la lente a implantar, así como el método ideal para su obtención: la interferometría óptica, sin olvidar la historia clínica previa al implante de la lente fáquica(AU)


Phakic intraocular lens implantation may be a logical option for extremely myopic patients who wish to get rid of their eyeglasses and contact lenses. This alternative was developed to correct extremely high degrees of myopia and remain inside the eye for many years. However, with the passing of time and due to physiological processes, the crystalline lens tends to become opaque. A new challenge is posed by the need to remove it and select a lens with an optical power appropriate to the capsular sac, thus achieving emmetropia. Inaccurate calculation of the dioptric power of the lens to be implanted in the surgical intervention is a problem leading to refractive surprise. Hence the interest in presenting a case illustrating the most common cause of refractive surprise after cataract surgery in a myopic patient with a phakic lens implant. The importance of axial length is highlighted, particularly whether it is modified after phakic lens implantation for accurate calculation of the lens to be implanted and the ideal method to obtain it: optical interferometry, without disregarding the medical record data preceding the phakic lens implantation(AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Operatórios/métodos , Extração de Catarata/métodos , Lentes Intraoculares Fácicas/efeitos adversos , Interferometria/métodos , Prontuários Médicos , Miopia/etiologia
4.
Clin Rheumatol ; 38(9): 2595-2602, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31144136

RESUMO

INTRODUCTION/OBJECTIVES: The prevalence of chondrocalcinosis (CC) was reported as variable according to the geographic populations. However, there are no data regarding its prevalence in Mexico. Thus, we decided to investigate the Mexican prevalence of CC in a cohort of patients from a tertiary health care institution. METHODS: A retrospective analysis of radiographs of knees and wrists from our institution was performed. Inclusion criteria included patients > 50 years old having radiographs of knees and wrists. Radiographic presence of CC was classified according to a dichotomous evaluation assayed by two rheumatologists experts on the area. RESULTS: A total of 3.350 radiographs from 1.602 patients were evaluated. Forty-seven patients showed calcifications in at least one knee or wrist for an overall prevalence of 3%, of which 23.4% were men and 76.6% women. The knee was more commonly affected than the wrist (85.1% and 14.9% respectively). The prevalence according to gender was 2.9% in women, whereas, it was 3.2% in men. Only two patients (4.3%) showed a contemporaneous presence of CC in both hands and both knees. At knee level, the prevalence was 2.7%, whereas at the wrist, we reported a prevalence of 4.9%. CONCLUSIONS: The prevalence of CC for Mexican population had not been reported so far. This a starting point to break the silence and encourage the knowledge of how this disease is associated with possible risk factors in Mexican population. Key Points •The prevalence of chondrocalcinosis in Mexico was 3%. •The prevalence of knee chondrocalcinosis increases according to the age in women's. •The nixtamalized meals could be a protective factor for CC in Mexican population.


Assuntos
Condrocalcinose/epidemiologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem , Idoso , Condrocalcinose/diagnóstico por imagem , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Radiografia , Centros de Atenção Terciária
5.
Molecules ; 24(1)2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30621198

RESUMO

Persea americana (avocado) is a fruit consumed worldwide; however, since avocado leaves are apparently a natural ingredient that can be used as a traditional medicine, they can be a potential source of bioactive compounds. This study aimed to analyze the antioxidant activity of seven Mexican avocado leaf extracts by DPPH•, ABTS•+, and lipid peroxidation (LPO), and to identify the compound profile by liquid chromatography coupled to mass spectrometry/electron spray ionization. The highest free radical-scavenging activity was observed for Platano Delgado and Criollo 6 avocado cultivars havin IC50 values of 271.86 ± 13.69 and 269.56 ± 6.53 for DPPH• and ABTS•+ radicals, respectively, while the best result for lipid oxidation inhibition was registered in Criollo 6 cultivar extract. In this study forty-one compounds were detected in avocado leaves of the the seven cultivars analyzed, and of these compounds, eighteen phenolics were identified for first time in such plant material. The present study demonstrated that Mexican cultivars of Persea americana possess diverse polyphenolic compounds with strong antioxidant activity, which might be useful in the food and pharmaceutical industries.


Assuntos
Antioxidantes/química , Persea/química , Extratos Vegetais/química , Polifenóis/química , Benzotiazóis/química , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/química , Peroxidação de Lipídeos/efeitos dos fármacos , Picratos/química , Folhas de Planta/química , Ácidos Sulfônicos/química
6.
Rev. cuba. oftalmol ; 31(3): 1-7, jul.-set. 2018. ilus
Artigo em Espanhol | LILACS | ID: biblio-985576

RESUMO

El anquilobléfaron es la fusión parcial o total de los bordes palpebrales. En dependencia de la localización, este puede clasificarse como medial o interno y lateral o externo. Es una malformación congénita que constituye una condición muy infrecuente. Puede estar genéticamente determinada, aunque su causa exacta o mecanismo de producción no se conoce claramente. El primer caso corresponde a una lactante femenina, de 57 días de nacida, antecedentes de madre con paladar hendido ya operado. Al examen oftalmológico se constata en el ojo derecho fusión a nivel de todo el borde palpebral y en el izquierdo brida hacia sector temporal, además de presentar paladar hendido. El segundo caso, es una paciente femenina de 24 meses de edad, que en el examen ocular se observa brida que fusiona ambos bordes palpebrales del ojo izquierdo, en zona temporal. Se confirma diagnóstico de anquilobléfaron. En el primer caso se decide, por la edad, mantener una conducta expectante y posponer el tratamiento quirúrgico hasta que se realice la cirugía de la fisura labial, la cual se realiza a los 3 meses. En ambos casos la conducta fue quirúrgica, con buenos resultados estéticos y funcionales. El diagnóstico de esta anomalía es clínico y el examen físico minucioso, el cual, unido a los conocimientos del especialista sobre estas anomalías, juega un papel primordial. El tratamiento siempre es quirúrgico, el procedimiento a ejecutar es sencillo, incluso cuando requiere de reconstrucción palpebral(AU)


Ankyloblepharon is the partial or total fusion of eyelid margins. According to its location, it may be classified as medial or internal and lateral or external. This congenital malformation is a very rare condition. Though it may be genetically determined, its exact cause or development mechanism is not clearly known. The first case is a 57-day-old female infant whose mother had undergone cleft palate surgery. Ophthalmological examination revealed fusion of the entire eyelid margin of the right eye and bridling toward the temporal sector of the left eye, as well as a cleft palate. The second case is a 24-month-old female patient whose ophthalmological examination revealed bridling fusing the two eyelid margins of the left eye in the temporal zone. Ankyloblepharon diagnosis was confirmed. In the first case, due to the patient's age it was decided to postpone surgical treatment until lip fissure surgery was performed at 3 months. In both cases management was surgical, with good esthetic and functional results. Diagnosis of this condition is based on meticulous clinical and physical examination, supported by the decisive role played by the specialist's knowledge about these anomalies. Treatment is always surgical and the procedure to be performed is simple, even when palpebral reconstruction is required(AU)


Assuntos
Humanos , Feminino , Lactente , Pré-Escolar , Anormalidades Congênitas/diagnóstico por imagem , Doenças Palpebrais/cirurgia , Glândulas Tarsais/anormalidades , Doenças do Recém-Nascido/diagnóstico
7.
Int. j. cardiovasc. sci. (Impr.) ; 30(2): f:145-l:156, mar.-abr. 2017. ilus, tab, graf
Artigo em Português | LILACS | ID: biblio-833920

RESUMO

Fundamento: A doença de Chagas é um problema de saúde global, sendo necessário o desenvolvimento de novos protocolos terapêuticos. Nosso grupo demonstrou recentemente que o nifurtimox associado ao dipiridamol tem efeitos curativos em camundongos com doença de Chagas aguda. Neste estudo, avaliamos o efeito deste protocolo terapêutico em camundongos chagásicos com insuficiência cardíaca. Objetivo: Avaliar se o nifurtimox e o dipiridamol são úteis no tratamento de resgate em camundongos com miocardite chagásica aguda com insuficiência cardíaca. Métodos: Foram divididos em três grupos 42 camundongos com miocardite chagásica aguda e insuficiência cardíaca congestiva: Controle Chagas (n = 11); Nif-Dip, tratados com nifurtimox e dipiridamol (n = 14); e Nif-Dip-Insuficiência Cardíaca, tratados com nifurtimox e dipiridamol, associados com digoxina, furosemida e captopril (n = 17). As doses de nifurtimox e dipiridamol foram de 40 e 30mg/kg/dia, respectivamente, durante 6 semanas. Os camundongos foram submetidos a avaliações clínicas, eletrocardiográficas, hemoparasitológicas e histopatológicas. Resultados: Observou-se menor mortalidade no Grupo Nif-Dip (n = 4; 28,57%) em relação ao Controle Chagas (n = 6; 54,54%) e ao Nif-Dip-Insuficiência Cardíaca (n = 9; 52,9%). Clinicamente, os camundongos tratados com nifurtimox e dipiridamol aumentaram o peso corporal e melhoraram a insuficiência cardíaca, sem mostrar esplenomegalia. Nestes grupos, foram erradicadas as parasitemias e os parasitas teciduais; a fibrose, a miocitólise, o infiltrado de células inflamatórias e os mastócitos diminuíram. Os distúrbios de repolarização, os intervalos QRS e o QT prolongados, o aumento da amplitude da onda S e a dissociação atrioventricular foram revertidos pelo tratamento. Conclusão: O tratamento com nifurtimox e dipiridamol pode ser usado no resgate em camundongos com doença chagásica aguda grave, já que o nifurtimox teve atividade tripanocida, e o dipiridamole potenciou seu efeito. O dipiridamol seria útil na insuficiência cardíaca chagásica


Background: Chagas disease is a global health problem; therefore, the development of new therapeutic protocols is necessary. Our group recently demonstrated that nifurtimox associated with dipyridamole has curative effects in mice with acute Chagas disease. In this study, we assess the effect of this therapeutic protocol in chagasic mice with heart failure. Objective: To evaluate whether nifurtimox and dipyridamole are useful to rescue mice with severe acute chagasic myocarditis with heart failure. Methods: 42 mice with acute chagasic myocarditis and congestive heart failure were divided into three groups: control chagas (n = 11), Nif-Dip treated with nifurtimox and dipyridamole (n = 14) and Nif-Dip-heart failure treated with nifurtimox and dipyridamole associated with digoxin, furosemide, and captopril (n = 17). Nifurtimox and dipyridamole doses were 40 and 30 mg/kg/day, respectively, for 6 weeks. Mice underwent clinical, electrocardiographic, hemoparasitological and histopathological assessments. Results: Lower mortality in Nif-Dip (28.57%; n = 4) compared to control chagas (54.54%; n = 6) and Nif-Dip-heart failure (52.9%; n = 9) was observed. Clinically, nifurtimox and dipyridamole-treated mice increased body weight and improved heart failure without splenomegaly. In these groups, parasitemia and tissue parasites were eradicated; fibrosis, myocytolysis, inflammatory cell infiltrate and mast cells decreased. Repolarization disorders, prolonged QRS and QT intervals, increase of S wave amplitude and atrioventricular dissociation were reversed by the treatment. Conclusion: Nifurtimox with dipyridamole can rescue NMRI mice from severe acute chagas disease, as nifurtimox showed trypanocidal activity and dipyridamole potentiated its effect. Dipyridamole would be useful in chagasic heart failure


Assuntos
Animais , Camundongos , Ratos , Cardiomiopatia Chagásica/mortalidade , Cardiomiopatia Chagásica/fisiopatologia , Doença de Chagas/mortalidade , Doença de Chagas/fisiopatologia , Dipiridamol/administração & dosagem , Dipiridamol/uso terapêutico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Camundongos , Nifurtimox/administração & dosagem , Nifurtimox/uso terapêutico , Análise de Variância , Doença Crônica , Protocolos Clínicos/normas , Eletrocardiografia/métodos , Modelos Animais , Mortalidade , Estatística como Assunto/métodos
8.
Sci. agric ; 69(1)2012.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1497257

RESUMO

Horse grazing systems may affect productivity and biodiversity of understory developed under Pinus radiata D. Don silvopastoral systems, while acting as a tool to reduce the risk of fire. This study compared continuous and rotational grazing systems effect upon biomass, fractions of stem, sprouts, leaves and woody parts of Ulex europaeus L. and alpha (Species Richness, Shannon-Wiener) and beta (Jaccard and Magurran) biodiversity for a period of four years in a P. radiata silvopastoral system. The experiment consisted of a randomized block design of two treatments (continuous and rotational grazing). Biomass, and species abundances were measured - biodiversity metrics were calculated based on these results for a two years of grazing and two years of post-grazing periods. Both continuous and rotational grazing systems were useful tools for reducing biomass and, therefore, fire risk. The rotational grazing system caused damage to the U. europaeus shrub, limiting its recovery once grazing was stopped. However, the more intensive grazing of U. europaeus plants under rotational had a positive effect on both alpha and beta biodiversity indexes due to the low capacity of food selection in the whole plot rather than continuous grazing systems. Biomass was not affected by the grazing system; however the rotational grazing system is more appropriate to reduce U. europaeus biomass and therefore forest fire risk at a long term and to enhance pasture biodiversity than the continuous grazing system.

9.
Sci. agric. ; 69(1)2012.
Artigo em Inglês | VETINDEX | ID: vti-440649

RESUMO

Horse grazing systems may affect productivity and biodiversity of understory developed under Pinus radiata D. Don silvopastoral systems, while acting as a tool to reduce the risk of fire. This study compared continuous and rotational grazing systems effect upon biomass, fractions of stem, sprouts, leaves and woody parts of Ulex europaeus L. and alpha (Species Richness, Shannon-Wiener) and beta (Jaccard and Magurran) biodiversity for a period of four years in a P. radiata silvopastoral system. The experiment consisted of a randomized block design of two treatments (continuous and rotational grazing). Biomass, and species abundances were measured - biodiversity metrics were calculated based on these results for a two years of grazing and two years of post-grazing periods. Both continuous and rotational grazing systems were useful tools for reducing biomass and, therefore, fire risk. The rotational grazing system caused damage to the U. europaeus shrub, limiting its recovery once grazing was stopped. However, the more intensive grazing of U. europaeus plants under rotational had a positive effect on both alpha and beta biodiversity indexes due to the low capacity of food selection in the whole plot rather than continuous grazing systems. Biomass was not affected by the grazing system; however the rotational grazing system is more appropriate to reduce U. europaeus biomass and therefore forest fire risk at a long term and to enhance pasture biodiversity than the continuous grazing system.

10.
Interciencia ; Interciencia;32(5): 303-311, mayo 2007. mapas, tab, graf
Artigo em Espanhol | LILACS | ID: lil-493135

RESUMO

En un bosque montano natural de roble (Quercus humboldtii Bonpl.) y en plantaciones forestales de pino pátula (Pinus patula Schltdl. y Cham.) y de ciprés (Cupressus lusitanica Mill.) de Piedras Blancas, Antioquia, Colombia, fueron medidos durante dos años los flujos de nutrientes a través de la hojarasca. En cada ecosistema se emplearon 20 trampas de hojarasca (0,5m² cada una) con el fin de recoger el material desprendido del dosel para su posterior separación en fracciones y análisis químico. Las cantidades de hojarasca fina siguieron el orden: pino pátula (8362,47 kg.ha-1. año-1), roble (7877,20 kg.ha-1. año-1) y ciprés (3725,97 kg.ha-1. año-1). Las cantidades de nutrientes que retornaron a través de la hojarasca foliar de la especie dominante en cada bosque fueron C>N>Ca>K>Mg>S>P en bosque de roble, C>N>P>Ca>Mg>K>S en plantación de pino pátula, y C>Ca>N>K>S>Mg>P en plantación de ciprés. Los resultados muestran un menor retorno de elementos hasta el piso del bosque en las plantaciones de coníferas y un retorno real posiblemente más lento como producto de los mayores valores de la relación C/N del material foliar de las especies de coníferas.


Assuntos
Folhas de Planta , Árvores , Colômbia , Ecologia
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