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1.
Science ; 381(6660): 877-886, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37616345

RESUMEN

Great efforts have been directed toward alkene π bond amination. In contrast, analogous functionalization of the adjacent C(sp3)-C(sp2) σ bonds is much rarer. Here we report how ozonolysis and copper catalysis under mild reaction conditions enable alkene C(sp3)-C(sp2) σ bond-rupturing cross-coupling reactions for the construction of new C(sp3)-N bonds. We have used this unconventional transformation for late-stage modification of hormones, pharmaceutical reagents, peptides, and nucleosides. Furthermore, we have coupled abundantly available terpenes and terpenoids with nitrogen nucleophiles to access artificial terpenoid alkaloids and complex chiral amines. In addition, we applied a commodity chemical, α-methylstyrene, as a methylation reagent to prepare methylated nucleosides directly from canonical nucleosides in one synthetic step. Our mechanistic investigation implicates an unusual copper ion pair cooperative process.

2.
J Cardiovasc Pharmacol ; 75(2): 180-184, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32023227

RESUMEN

Rivaroxaban is a direct oral anti-factor Xa anticoagulant. It has recently been suggested that rivaroxaban may affect platelet function in vitro; however, little is known about the clinical impact of this likely antiplatelet effect and whether this probable phenomenon is dose-dependent. Our aim was to determine whether rivaroxaban at 4 different doses inhibits direct platelet aggregation. We included adult patients of both sexes and who were allocated to one of the following groups depending on the prescribed daily dose of rivaroxaban: 5, 10, 15, and 20 mg. In 80 patients (20 patients/group), the percentage of platelet aggregation was determined by means of platelet aggregometry tests before and after rivaroxaban use. Basal samples were obtained before starting rivaroxaban and 1 month after treatment, both 2 and 24 hours after the last dose of the drug (12 hours after in the case of rivaroxaban 5 mg). We used 5 platelet agonists: adenosine diphosphate, epinephrine, arachidonic acid, collagen, and thrombin. There were no significant changes in the percentage of platelet aggregation before and after rivaroxaban use independently of the dose administered and the agonist used. Our results have clearly shown that rivaroxaban, even at a high dose, does not directly affect platelet aggregation.


Asunto(s)
Inhibidores del Factor Xa/administración & dosificación , Agregación Plaquetaria/efectos de los fármacos , Rivaroxabán/administración & dosificación , Adolescente , Adulto , Anciano , Inhibidores del Factor Xa/efectos adversos , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pruebas de Función Plaquetaria , Estudios Prospectivos , Rivaroxabán/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
3.
Sci Rep ; 6: 35346, 2016 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-27739479

RESUMEN

Carotenoids are important dietary nutrients with health-promoting effects. The biofortification of staple foods with carotenoids provides an efficient delivery strategy but little is known about the fate and distribution of carotenoids supplied in this manner. The chicken provides a good model of human carotenoid metabolism so we supplemented the diets of laying hens using two biofortified maize varieties with distinct carotenoid profiles and compared the fate of the different carotenoids in terms of distribution in the feed, the hen's livers and the eggs. We found that after a period of depletion, pro-vitamin A (PVA) carotenoids were preferentially diverted to the liver and relatively depleted in the eggs, whereas other carotenoids were transported to the eggs even when the liver remained depleted. When retinol was included in the diet, it accumulated more in the eggs than the livers, whereas PVA carotenoids showed the opposite profile. Our data suggest that a transport nexus from the intestinal lumen to the eggs introduces bottlenecks that cause chemically-distinct classes of carotenoids to be partitioned in different ways. This nexus model will allow us to optimize animal feed and human diets to ensure that the health benefits of carotenoids are delivered in the most effective manner.

4.
Microbes Infect ; 16(9): 755-61, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25016144

RESUMEN

The increasing number of people with type 2 diabetes (DM2) is alarming and if it is taken into account that the relative odds of developing tuberculosis in diabetic patients ranges from 2.44 to 8.33 compared with non-diabetic patients, thus in developing countries where these two diseases are encountering face to face, there is a need for prophylaxis strategies. The role of vitamin D has been widely implicated in growth control of Mycobacterium tuberculosis (Mtb) during primary infection mainly through the induction of certain antimicrobial peptides (AMPs). In this study we evaluated the vitamin D serum levels, CYP27B1-hydroxylase enzyme, vitamin D receptor (VDR) and AMPs gene expression in Healthy donors, DM2 and TB patients. Results showed that DM2 group has lower VDR and AMPs expression levels. When Monocytes Derived Macrophages (MDM) from DM2 patients with low VDR expression were supplemented with vitamin D, MDMs eliminate efficiently M. tuberculosis. This preliminary study suggests the use of vitamin D as prophylaxis for tuberculosis in high DM2 endemic countries.


Asunto(s)
Diabetes Mellitus Tipo 2/microbiología , Macrófagos/fisiología , Mycobacterium tuberculosis , Vitamina D/farmacología , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Adulto , Anciano , Péptidos Catiónicos Antimicrobianos/genética , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/microbiología , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/crecimiento & desarrollo , Receptores de Calcitriol/sangre , Receptores de Calcitriol/genética , Vitamina D/administración & dosificación , Vitamina D/sangre , Adulto Joven
5.
Endocrinology ; 149(5): 2657-66, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18218697

RESUMEN

Alterations in motor functions are well-characterized features observed in humans and experimental animals subjected to thyroid hormone dysfunctions during development. Here we show that congenitally hypothyroid rats display hyperactivity in the adult life. This phenotype was associated with a decreased content of cannabinoid receptor type 1 (CB(1)) mRNA in the striatum and a reduction in the number of binding sites in both striatum and projection areas. These findings suggest that hyperactivity may be the consequence of a thyroid hormone deficiency-induced removal of the endocannabinoid tone, normally acting as a brake for hyperactivity at the basal ganglia. In agreement with the decrease in CB(1) receptor gene expression, a lower cannabinoid response, measured by biochemical, genetic and behavioral parameters, was observed in the hypothyroid animals. Finally, both CB(1) receptor gene expression and the biochemical and behavioral dysfunctions found in the hypothyroid animals were improved after a thyroid hormone replacement treatment. Thus, the present study suggests that impairment in the endocannabinoid system can underlay the hyperactive phenotype associated with hypothyroidism.


Asunto(s)
Moduladores de Receptores de Cannabinoides/fisiología , Hipotiroidismo Congénito/complicaciones , Endocannabinoides , Hipercinesia/etiología , Animales , Animales Recién Nacidos , Ganglios Basales/efectos de los fármacos , Ganglios Basales/metabolismo , Conducta Animal/efectos de los fármacos , Moduladores de Receptores de Cannabinoides/agonistas , Moduladores de Receptores de Cannabinoides/metabolismo , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , Hipotiroidismo Congénito/fisiopatología , Evaluación Preclínica de Medicamentos , Femenino , Hipercinesia/tratamiento farmacológico , Hipercinesia/genética , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Embarazo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB1/metabolismo , Triyodotironina/farmacología , Triyodotironina/uso terapéutico
6.
Neuropsychopharmacology ; 32(11): 2260-6, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17392740

RESUMEN

The co-abuse of marijuana with cocaine is widespread, but it has not been until recently that the relationship between the behavioral effects of cannabinoids and cocaine has begun to be unveiled in animal models. Male Wistar rats were trained to intravenously self-administer cocaine until a stable baseline was reached. Rats then were subjected to a 5-day cocaine deprivation period during which they were treated daily with the cannabinoid receptor agonist WIN 55,212-2 (R-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate) (0, 0.3, 1, and 3 mg/kg; i.p.). Following this subchronic treatment, rats were tested, in counterbalanced order, in a test of anxiety (elevated plus-maze), as well as extinction and cue-induced reinstatement tests, the latter conducted according to a between-within procedure. Subchronic administration of WIN 55,212-2 was found to produce dose-dependent alterations of performance in the extinction, reinstatement, and anxiety tests with the lowest dose of WIN 55,212-2 producing the highest resistance to extinction and reinstatement, and the highest dose of WIN 55,212-2 producing the highest anxiolytic activity. Subchronic treatment with WIN 55,212-2 in rats without a history of cocaine self-administration did not affect anxiety levels. The results suggest an important role of the cannabinoid system in neuronal processes underlying cocaine seeking behavior. However, further studies will be necessary to understand possible implications of these findings for a role of the cannabinoid system as a treatment target for human cocaine abuse.


Asunto(s)
Analgésicos/uso terapéutico , Benzoxazinas/uso terapéutico , Cocaína/efectos adversos , Morfolinas/uso terapéutico , Naftalenos/uso terapéutico , Síndrome de Abstinencia a Sustancias/psicología , Animales , Conducta Animal/efectos de los fármacos , Cocaína/administración & dosificación , Condicionamiento Operante/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Extinción Psicológica/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratas , Ratas Wistar , Autoadministración/métodos , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/etiología
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