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1.
Trop Anim Health Prod ; 56(5): 171, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38769268

RESUMEN

Elephant grass [Pennisetum purpureum Schumach. syn. Cenchrus purpureus (Schumach.) Morrone], also known as Napier grass and King grass, includes varieties Taiwán, Gigante, Merkerón, Maralfalfa, and others. The grass achieves high biomass production in tropical-subtropical, temperate, and arid areas. The high-water concentration of elephant grass suggests that ensiling could offer an alternative way to preserve the nutritional quality of the grass during storage, however, some considerations should be addressed because of the particularities of the grass. Ensiling elephant grass may produce adequate fermentation but could suffer effluent losses and subsequent losses of nutrients due to leaching. To improve fermentation and nutrient characteristics of elephant grass silages, several studies were conducted with the inclusion of additives. Lactic acid bacteria inocula have reduced pH and increased crude protein content of elephant grass silage, but aerobic stability of silages could be affected by the bacterial inoculation. There is limited information, however, on the potential of different silage inoculants to reduce growth of spoilage microorganisms during the aerobic phase of silage prepared with elephant grass. Exogenous fibrolytic enzymes also may improve elephant grass silage quality by enhancing microbial fiber-degradation with subsequent increase in lactic acid and its associated pH reduction. Another study approach to improve fermentation and nutritional quality of elephant grass silages involved the addition of different feeds at ensiling, including conventional feeds such corn, wheat, rice bran, and molasses or alternative feeds such as different dehydrated by-products obtained from the food industries of juice and jelly. In the manuscript, the presented scientific information shows the great potential of the different manipulations to improve the quality of elephant grass silages and with possible enhance of the economic profit and sustainability of livestock farming in the tropical areas.


Asunto(s)
Fermentación , Valor Nutritivo , Ensilaje , Ensilaje/análisis , Animales , Cenchrus , Pennisetum
2.
ACS Med Chem Lett ; 12(11): 1794-1801, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34795869

RESUMEN

The PI3K/AKT/mTOR and PIM kinase pathways contribute to the development of several hallmarks of cancer. Cotargeting of these pathways has exhibited promising synergistic therapeutic effects in liquid and solid tumor types. To identify molecules with combined activities, we cross-screened our collection of PI3K/(±mTOR) macrocycles (MCXs) and identified the MCX thieno[3,2-d]pyrimidine derivative 2 as a moderate dual PI3K/PIM-1 inhibitor. We report the medicinal chemistry exploration and biological characterization of a series of thieno[3,2-d]pyrimidine MCXs, which led to the discovery of IBL-302 (31), a potent, selective, and orally bioavailable triple PI3K/mTOR/PIM inhibitor. IBL-302, currently in late preclinical development (AUM302), has recently demonstrated efficacy in neuroblastoma and breast cancer xenografts. Additionally, during the course of our experiments, we observed that macrocyclization was essential to obtain the desired multitarget profile. As a matter of example, the open precursors 35-37 were inactive against PIM whereas MCX 28 displayed low nanomolar activity.

4.
Eur J Med Chem ; 211: 113109, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33360802

RESUMEN

Activation of the phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway occurs frequently in a wide range of human cancers and is a main driver of cell growth, proliferation, survival, and chemoresistance of cancer cells. Compounds targeting this pathway are under active development as anticancer therapeutics and some of them have reached advanced clinical trials or been approved by the FDA. Dual PI3K/mTOR inhibitors combine multiple therapeutic efficacies in a single molecule by inhibiting the pathway both upstream and downstream of AKT. Herein, we report our efforts on the exploration of novel small molecule macrocycles (MCXs) as dual PI3K/mTOR inhibitors. Macrocyclization is an attractive approach used in drug discovery, as the semi-rigid character of these structures could provide improved potency, selectivity and favorable pharmacokinetic properties. Importantly, this strategy allows access to new chemical space thus obtaining a better intellectual property position. A series of MCXs based on GSK-2126458, a known clinical PI3K/mTOR inhibitor is described. These molecules showed potent biochemical and cellular dual PI3K/mTOR inhibition, demonstrated strong antitumoral effects in human cancer cell lines, and displayed good drug-like properties. Among them, MCX 83 presented remarkable selectivity against a panel of 468 kinases, high in vitro metabolic stability, and favorable pharmacokinetic parameters without significant CYP450 and h-ERG binding inhibition. This profile qualified this compound as a suitable candidate for future in vivo PK-PD and efficacy studies in mouse cancer models.


Asunto(s)
Fosfatidilinositol 3-Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinolinas/uso terapéutico , Sulfonamidas/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismo , Humanos , Fosfatidilinositol 3-Quinasas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Piridazinas , Quinolinas/farmacología , Sulfonamidas/farmacología
5.
Exp Parasitol ; 218: 107980, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32877640

RESUMEN

Acacia farnesiana pods are rich in secondary metabolites and their biological activities have been recorded as antibacterial, antioxidant and anthelmintic. Previously, an in vitro bioguided study showed the important ovicidal and larvicidal effects of an organic fraction (EtOAc-F) from a hydroalcoholic extract of A. farnesiana pods against Haemonchus contortus. The present study aimed to assess the in vivo anthelmintic effect of EtOAc-F from A. farnesiana pods on the H. contortus faecal egg elimination in female lambs and on the infective larvae (L3) population reduction in coprocultures. The EtOAc-F was obtained from a hydroalcoholic extract from A. farnesiana pods through chromatographic procedures; additionally, some secondary compounds were identified using high-performance liquid chromatography (HPLC). Twenty-one 'Katahdin' crossbred female lambs ranging from three to four months of age, with body weights 21.9 ± 0.39 kg were used. Animals were orally infected with H. contortus (L3) by a single dose of 350 L3/kg BW. Three experimental groups (n = 7) were assigned as follows: 1) Control (untreated), 2) Albendazole, as a positive control (at 7.5 mg/kg BW, unique dose) and 3) EtOAc-F (at 100 mg/kg BW, once every third day, with three applications in total). Individual faecal samples were collected once a week for 5 weeks (at days 38, 45, 52, 59 and 66) post-treatment, to measure the faecal egg counts (FEC) and to obtain the H. contortus (L3) population from faecal cultures. The highest FEC reduction caused by EtOAc-F was 67.7%; meanwhile, albendazole showed a total FEC reduction after the second week post-treatment (day 45). On the other hand, the fraction caused an important reduction in the larval population in coprocultures (54.3-68.5%). The phytochemical analysis revealed the presence of galloyl derivatives and flavonoids as major compounds. The A. farnesiana pods could serve as a natural anthelmintic for the control of H. contortus, and perhaps for controlling other parasites of veterinary importance.


Asunto(s)
Acacia/química , Antihelmínticos/uso terapéutico , Hemoncosis/veterinaria , Extractos Vegetales/uso terapéutico , Enfermedades de las Ovejas/tratamiento farmacológico , Animales , Antihelmínticos/aislamiento & purificación , Antihelmínticos/farmacología , Heces/parasitología , Femenino , Flavonoides/química , Ácido Gálico/química , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Haemonchus/efectos de los fármacos , Haemonchus/aislamiento & purificación , Hematócrito/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/parasitología
6.
Eur J Med Chem ; 201: 112443, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32599324

RESUMEN

CDK8 is a cyclin-dependent kinase that forms part of the mediator complex, and modulates the transcriptional output from distinct transcription factors involved in oncogenic control. Overexpression of CDK8 has been observed in various cancers, representing a potential target for developing novel CDK8 inhibitors in cancer therapeutics. In the course of our investigations to discover new CDK8 inhibitors, we designed and synthesized tricyclic pyrido[2,3-b][1,5]benzoxazepin-5(6H)-one derivatives, by introduction of chemical complexity in the multi-kinase inhibitor Sorafenib taking into account the flexibility of the P-loop motif of CDK8 protein observed after analysis of structural information of co-crystallized CDK8 inhibitors. In vitro evaluation of the inhibitory activity of the prepared compounds against CDK8 led us to identify compound 2 as the most potent inhibitor of the series (IC50 = 8.25 nM). Co-crystal studies and the remarkable selectivity profile of compound 2 are presented. Compound 2 showed moderate reduction of phosphorylation of CDK8 substrate STAT1 in cells, in line with other reported Type II CDK8 inhibitors. We propose herein an alternative to find a potential therapeutic use for this chemical series.


Asunto(s)
Quinasa 8 Dependiente de Ciclina/antagonistas & inhibidores , Oxazepinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Sorafenib/análogos & derivados , Sorafenib/farmacología , Línea Celular Tumoral , Diseño de Fármacos , Humanos , Estructura Molecular , Oxazepinas/síntesis química , Inhibidores de Proteínas Quinasas/síntesis química , Piridinas/síntesis química , Relación Estructura-Actividad
7.
J Ethnopharmacol ; 249: 112402, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31739102

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Acacia farnesiana (L.) Willd is a shrub legume used as condiment, medicinal plant and bioactive herbage. This species is used in traditional medicine of several countries to relieve the symptoms of gastrointestinal diseases, diarrhoea, stomach pain and typhoid as well as astringent, antidysenteric and anthelmintic. Some studies have shown that this plant displayed anthelmintic activity against several gastrointestinal nematode parasites of livestock, and also against parasites of human beings, such as malaria. AIM OF THE STUDY: This work describes the isolation and chemical identification of the anthelmintic compounds of Acacia farnesiana pods against eggs and infective larvae of the sheep parasitic nematode Haemonchus contortus. The bio-guided chemical fractioning of A. farnesiana pods using ethyl acetate against H. contortus eggs and infective larvae allowed for the identification of naringenin 7-O-(6″-galloylglucoside) (flavonol group) as the compound responsible for the anthelmintic activity against this important parasitic nematode. MATERIALS AND METHODS: Anthelmintic activity was assessed using the egg hatching inhibition assay (EHI) and mortality tests. A complete hydroalcoholic extract (HA-E) at 12.5-50 mg/mL, an aqueous fraction (Aq-F) at 3.12-25 mg/mL and an ethyl acetate fraction (EtOAc-F) at 3.12-25 mg/mL were analysed in the first selection phase. The purification of compounds through the chromatographic separation of the organic fraction resulted in nine less complex mixtures (C1F1, C1F2, C1F3, C1F4, C2F1, C2F2, C2F3, C2F4 and C2F5) that were assessed at 0.62-5 mg/mL concentrations. In addition, thiabendazole (0.6 mg/mL) and ivermectin (5 mg/mL) were used as positive controls. Likewise, distilled water and 4% methanol were used as negative controls. The bioactive compounds of EtOAc-F were obtained and characterised through chromatographic processes like open column chromatography, thin layer chromatography (TLC), high performance liquid chromatography (HPLC), ultra-performance liquid chromatography (UPLC) and gass chromatography-mass detection (GC-MS). Bioactive compounds were identified by spectroscopy (1H and 13C NMR) and mass spectrometric analysis. Additionally, the H. contortus eggs and infective larvae exposed to the bioactive compounds were observed through environmental scanning electron microscopy (ESEM) and confocal laser scanning microscopy (CLSM). Data were analysed based on a completely randomised design using ANOVA through a general linear model. RESULTS: The EtOAc-F fraction showed the highest ovicidal and larvicidal activities, at close to 100% at 3.12 and 6.25 mg/mL, respectively. The treatments C1F2, C1F3 and C2F3 displayed the main ovicidal activity (80-100%) at 2.5 mg/mL. The major compounds found in these sub-fractions were identified as galloyl derivatives and flavanones, including gallic acid (1), methyl gallate (2), ethyl gallate (3), naringin (4), naringenin 7-O-(4″, 6″-digalloylglucoside) (5), naringenin 7-O-(6″-galloylglucoside) (6) and naringenin (7). Likewise, the ESEM and CLSM images showed that the assessed compounds adhered to the eggshell and the external cuticle of the larvae. CONCLUSION: These results indicate that A. farnesiana pods contain nematocidal compounds and might be promising natural anthelmintic agents against H. contortus. This leguminous plant could be used as a nutraceutical food source for the control of gastrointestinal nematodes in small ruminants.


Asunto(s)
Acacia/química , Antinematodos/farmacología , Hemoncosis/tratamiento farmacológico , Haemonchus/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Antinematodos/aislamiento & purificación , Antinematodos/uso terapéutico , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Flavonoides/uso terapéutico , Hemoncosis/parasitología , Hemoncosis/veterinaria , Larva/efectos de los fármacos , Óvulo/efectos de los fármacos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Ovinos/parasitología
10.
Clin Psychol Psychother ; 23(2): 183-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-25801527

RESUMEN

UNLABELLED: The purpose of this study was to adapt the 'Voice and You' Scale (VAY) (Hayward, Denney, Vaughan, & Fowler, 2008) to Spanish and explore its psychometric properties for measuring the perceived relationship with voices. A sample of 50 psychiatric patients with verbal auditory hallucinations (48 had a psychotic disorder and two a borderline personality disorder) was used. Its reliability was calculated using the Cronbach's α and test-retest, and concurrent validity by the Pearson correlation coefficient of the VAY with the Beliefs About Voices Questionnaire and the Psychotic Symptom Rating Scales. The results showed that internal consistency of the Spanish version of the VAY ranged from 0.74 to 0.84 on the various subscales, and test-retest reliability varied from 0.74 to 0.83 on three subscales (voice 'dominance', 'intrusiveness' and hearer 'dependence'), and was lower (0.68) on the hearer 'distance' subscale. Concurrent validity was acceptable as significant associations were found with the Beliefs About Voices Questionnaire and the Psychotic Symptom Rating Scales subscales. It is concluded that the Spanish version of the VAY is a reliable and valid instrument that can assist the exploration of voices within relational frameworks across research and clinical domains. KEY PRACTITIONER MESSAGE: The Spanish version of the VAY is a reliable, valid instrument for evaluating the perception a person can have about his or her relationship with the voices and how the person relates to them. Voices that are perceived as relating dominantly and intrusively, and from whom distance is sought, seem to be distressing and cause disturbance. Voices that are related to dependently are perceived as having benevolent intent and are engaged with. Benevolent or neutral voices may be considered as intrusive because of the intensity and frequency with which they are experienced.


Asunto(s)
Alucinaciones/psicología , Encuestas y Cuestionarios/normas , Traducción , Adolescente , Adulto , Anciano , Trastorno de Personalidad Limítrofe/complicaciones , Trastorno de Personalidad Limítrofe/psicología , Femenino , Alucinaciones/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Psicometría , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/psicología , Reproducibilidad de los Resultados , España , Adulto Joven
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