Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Science ; 361(6404)2018 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-30139845

RESUMEN

Kroodsma et al (Reports, 23 February 2018, p. 904) mapped the global footprint of fisheries. Their estimates of footprint and resulting contrasts between the scale of fishing and agriculture are an artifact of the spatial scale of analysis. Reanalyses of their global (all vessels) and regional (trawling) data at higher resolution reduced footprint estimates by factors of >10 and >5, respectively.


Asunto(s)
Agricultura , Explotaciones Pesqueras , Conservación de los Recursos Naturales , Peces
2.
J Biol Regul Homeost Agents ; 31(3): 589-601, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28889799

RESUMEN

Resveratrol (3,4',5-trihydroxy-trans-stilbene) is a natural phytoalexin found in grapes and wine, which has been extensively studied for a wide range of biological effects. A large number of stilbene-containing derivatives have displayed antioxidant and antiproliferative activities on various cancer cell lines. In this study, a series of stilbene hybrids 1-9, previously reported as peroxisome proliferator-activated receptor (PPAR) agonists, were assessed at micromolar concentrations using MTT cell viability assay in C2C12 and MCF7 cell lines. The modulation of oxidative stress was also evaluated by measuring the protective effects on reactive oxygen species (ROS) production induced or not by oxidative stimulus. Among these, compounds 2 and 8 showed significant radical scavenging activity.


Asunto(s)
Estrés Oxidativo/efectos de los fármacos , Receptores Activados del Proliferador del Peroxisoma/agonistas , Especies Reactivas de Oxígeno/metabolismo , Estilbenos/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Humanos , Células MCF-7 , Ratones , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Resveratrol
3.
Eur Rev Med Pharmacol Sci ; 21(4): 657-661, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28272720

RESUMEN

OBJECTIVE: The use of gonadotropin-releasing hormone agonist for ovulation triggering has become an intriguing topic in the last few years. As long as adequate luteal phase support is provided, it may be a valuable alternative to standard hCG triggering, associated with a significant reduction in OHSS incidence. Several luteal phase support options have been proposed, but few studies have addressed the issue of the appropriate route for progesterone administration to women triggered with GnRHa. The aim of the study was to evaluate the effect of GnRHa triggering on IVF/ICSI outcomes, using modified luteal phase support with intramuscular progesterone. PATIENTS AND METHODS: A retrospective study was carried out between January 2014 and December 2015, comparing the reproductive outcome in GnRHa triggered women given modified luteal phase support with intramuscular progesterone (Group A) with the outcome in women triggered with standard hCG (Group B) in IVF/ICSI cycles. RESULTS: 200 (Group A n = 100; Group B n = 100) consecutive normoresponder women were included. No differences with respect to Age, BMI, basal FSH, basal Estradiol and infertility diagnosis were observed between groups. Increased numbers of retrieved oocytes (8.1 ± 3.3 versus 6.8 ± 3.5, p = 0.009) and mature oocytes (5.8 ± 2.6 versus 5.1 ± 2.7, p = 0.03) were detected in Group A compared with Group B. Implantation, biochemical pregnancy and ongoing pregnancy rates were similar. CONCLUSIONS: Our findings confirmed that the GnRHa triggering strategy is associated with increased number of oocytes retrieved and of mature oocytes even in normoresponder women. Moreover, in these patients, the use of intramuscular progesterone during luteal phase support achieved satisfactory IVF outcomes.


Asunto(s)
Fertilización In Vitro , Fase Luteínica , Progesterona/administración & dosificación , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Inyecciones Intramusculares , Inducción de la Ovulación , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Adulto Joven
4.
Appl Environ Microbiol ; 75(12): 4155-61, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19395576

RESUMEN

Several hepatitis A virus (HAV) and human norovirus (HuNoV) outbreaks due to consumption of contaminated berries and vegetables have recently been reported. Model experiments were performed to determine the effectiveness of freeze-drying, freeze-drying combined with heating, and steam blanching for inactivation of enteric viruses that might be present on the surface of berries and herbs. Inactivation of HAV and inactivation of feline calicivirus, a surrogate for HuNoV, were assessed by viral culturing and quantitative reverse transcription PCR (RT-PCR), whereas HuNoV survival was determined only by quantitative RT-PCR. While freeze-drying barely reduced (<1.3 log(10) units) the amount of HAV RNA detected in frozen produce, a greater decline in HAV infectivity was observed. The resistance of HuNoV genogroup I (GI) to freeze-drying was significantly higher than that of HuNoV GII on berries. Addition of a terminal dry heat treatment at 120 degrees C after freeze-drying enhanced virus inactivation by at least 2 log(10) units, except for HuNoV GII. The results suggest that steam blanching at 95 degrees C for 2.5 min effectively inactivated infectious enteric viruses if they were present in herbs. Our results provide data for adjusting food processing technologies if viral contamination of raw materials is suspected.


Asunto(s)
Desinfección/métodos , Frutas/virología , Viabilidad Microbiana , Plantas Medicinales/virología , Inactivación de Virus , Calicivirus Felino/aislamiento & purificación , Liofilización/métodos , Calefacción/métodos , Virus de la Hepatitis A/aislamiento & purificación , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Cultivo de Virus
6.
Chirality ; 13(2): 102-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11170253

RESUMEN

2-Bromoesters enriched in the (S,R)-diastereoisomer can be easily prepared by coupling of racemic 2-bromoacids with (R)-pantolactone. Displacement of the bromine atom with nucleophiles, under suitable reaction conditions, occurs without epimerization of starting compounds, giving (R,R)-2-substituted carboxylic acid derivatives.

7.
Chirality ; 12(10): 697-704, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11054827

RESUMEN

Some chiral analogs of clofibric acid, the active metabolite of the antilipidemic drug clofibrate, show different configurational stability in basic conditions. Also, extensive racemization occurs when the corresponding optically active acid chlorides are treated with 3 alpha-tropanol, whereas no racemization takes place with 3 alpha-tropanol as hydrochloride salt and with 3 beta-tropanol and 1-methyl-4-hydroxy-piperidine as either the free base or hydrochloride salt. For these aminoalcohols, experimental evidence supports the hypothesis that a ketene intermediate is involved in the racemization process. Formation of intramolecular hydrogen bond is evoked to explain the different ability of aminoalcohols to induce ketene formation and consequent racemization.


Asunto(s)
Ácido Clofíbrico/análogos & derivados , Ácido Clofíbrico/química , Clofibrato/química , Ésteres , Hidrólisis , Hipolipemiantes/química , Indicadores y Reactivos , Conformación Molecular , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad
8.
J Neurosurg Sci ; 43(2): 125-32; discussion 133, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10735766

RESUMEN

BACKGROUND: The infection of the external ventricular drainage (EDV) remains the main morbidity and mortality associated with this procedure, in the setting of the treatment of hydrocephalus and its complications, leading to excess of hospitalization with annual economic burden. METHODS. In this 3-year retrospective study we selected and reviewed the records of 15 of 143 patients (mean age 34 years with range from 1 months to 70 years; 12 males and 3 females) undergone to prolonged EVD in the setting of management of hydrocephalus (5 patients because of acute ventricular dilation post-intraventricular hemorrhage or post-hemorrhagic HCP, 8 because of V-P shunt infection, 1 because of post-traumatic HCP and 1 because of shunt malfunction by elevated CSF protein) and developing a shunt infection or one or more superinfection. RESULTS: There was a 26% mortality and a 13% morbidity (1 patient had GOS score of 2, 1 score of 3 and 3 score of 5). The pathogens yielded by CSF culture were normal or transient flora of the patient's skin. The causes of infection were carefully analyzed. CONCLUSIONS: Based on our experience the management of infection in long-term EVD includes: the standardization of the environment of the surgery achieved with a) use of prophylactic antibiotics; b) preparation of the patient and sterile field; c) no touch technique. After implantation of EVD the risk of infection must be minimized by carefully nursing care of EVD, and administration of above prophylactic antibiotics. CSF must be collected for culture and cell count, glucose and protein when clinically indicated. When infection o reinfection is demonstrated by CSF culture then it is advisable to remove the entire hardware and start the antibiotic therapy intravenously and intraventricularly basing on susceptibility tests, CSF penetration of antibiotics, their bactericidal action, toxicity, specificity and cost. Regard to the duration of the therapy, a practical guide is treating for 10-14 days after three consecutive CSF sterile cultures. Thus, convention of EVD to a shunt can be performed within 3 weeks from admission, in the best favourable cases, decreasing the duration of hospital stay and the overall cost of neurosurgical management of the cerebral pathology requiring as therapeutic adjunct and EVD.


Asunto(s)
Infecciones Bacterianas del Sistema Nervioso Central/etiología , Derivaciones del Líquido Cefalorraquídeo/efectos adversos , Hidrocefalia/cirugía , Complicaciones Posoperatorias/etiología , Ventriculostomía/efectos adversos , Adulto , Anciano , Antibacterianos/uso terapéutico , Infecciones Bacterianas del Sistema Nervioso Central/microbiología , Infecciones Bacterianas del Sistema Nervioso Central/prevención & control , Niño , Femenino , Humanos , Hidrocefalia/complicaciones , Lactante , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/microbiología , Complicaciones Posoperatorias/prevención & control , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
9.
Farmaco ; 52(6-7): 367-74, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9372587

RESUMEN

Both racemic and enantiomeric forms of some isosteres of chiral clofibric acid analogs have been synthesized. Also, the absolute configuration has been established by chemical correlation and the optical purity determined by a simple HPLC procedure. Moreover, these studies show that the isosteric substitution of the ether oxygen atom of alpha-aryloxy-alkanoic acids with sulfur, amino and methylene groups lead to compounds in which both biological activity and stereoselectivity regarding chloride channel are highly reduced.


Asunto(s)
Ácido Clofíbrico/análogos & derivados , Ácido Clofíbrico/química , Animales , Canales de Cloruro/efectos de los fármacos , Canales de Cloruro/fisiología , Cromatografía Líquida de Alta Presión , Ácido Clofíbrico/síntesis química , Ácido Clofíbrico/aislamiento & purificación , Conformación Molecular , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Ratas , Estereoisomerismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA