54 research outputs found
Reversal of diastereoselectivity in the synthesis of Peptidomimetic 3âCarboxamide-1,4-benzodiazepin-5-ones
Enantiopure 3-carboxamide-1,4-benzodiazepin-5-ones were synthesized via the Ugi reaction followed by the Staudinger/aza-Wittig or reduction reactions in only two steps. A complete reversal of diastereoselectivity was achieved depending on the cyclization methodology employed. The different orientation of the C3 substituent in our 3-substituted 1,4-benzodiazepin-5-ones with respect to the most studied 1,4-benzodiazepin-2-ones makes them complementary in the development of new drugs because the primary source of binding selectivity of 1,4-benzodiazepines is the selective recognition of ligand conformations by the receptor.Ministerio de EconomiÌa y Competitividad, Spain (Project CTQ2012-31611), Junta de Castilla y LeoÌn, ConsejeriÌa de EducacioÌn y Cultura y Fondo Social Europeo (Project BU246A12-1) and the European Commission, Seventh Framework Programme (Project SNIFFER FP7-SEC-2012-312411)
Oxidative stress in the developing brain: effects of postnatal glucocorticoid therapy and antioxidants in the rat.
In premature infants, glucocorticoids ameliorate chronic lung disease, but have adverse effects on long-term neurological function. Glucocorticoid excess promotes free radical overproduction. We hypothesised that the adverse effects of postnatal glucocorticoid therapy on the developing brain are secondary to oxidative stress and that antioxidant treatment would diminish unwanted effects. Male rat pups received a clinically-relevant tapering course of dexamethasone (DEX; 0.5, 0.3, and 0.1 mg x kg(-1) x day(-1)), with or without antioxidant vitamins C and E (DEXCE; 200 mg x kg(-1) x day(-1) and 100 mg x kg(-1) x day(-1), respectively), on postnatal days 1-6 (P1-6). Controls received saline or saline with vitamins. At weaning, relative to controls, DEX decreased total brain volume (704.4±34.7 mm(3) vs. 564.0±20.0 mm(3)), the soma volume of neurons in the CA1 (1172.6±30.4 ”m(3) vs. 1002.4±11.8 ”m(3)) and in the dentate gyrus (525.9±27.2 ”m(3) vs. 421.5±24.6 ”m(3)) of the hippocampus, and induced oxidative stress in the cortex (protein expression: heat shock protein 70 [Hsp70]: +68%; 4-hydroxynonenal [4-HNE]: +118% and nitrotyrosine [NT]: +20%). Dexamethasone in combination with vitamins resulted in improvements in total brain volume (637.5±43.1 mm(3)), and soma volume of neurons in the CA1 (1157.5±42.4 ”m(3)) and the dentate gyrus (536.1±27.2 ”m(3)). Hsp70 protein expression was unaltered in the cortex (+9%), however, 4-HNE (+95%) and NT (+24%) protein expression remained upregulated. Treatment of neonates with vitamins alone induced oxidative stress in the cortex (Hsp70: +67%; 4-HNE: +73%; NT: +22%) and in the hippocampus (NT: +35%). Combined glucocorticoid and antioxidant therapy in premature infants may be safer for the developing brain than glucocorticoids alone in the treatment of chronic lung disease. However, antioxidant therapy in healthy offspring is not recommended
Collateral Damage: Educational Attainment and Labor Market Outcomes Among German War and Post-War Cohorts
We use data from the West German 1970 census to explore the link between being born during or shortly after World War II and educational and labor market outcomes 25 years later. We document, for the first time, that men and women born in the relatively short period between November 1945 and May 1946 have significantly and substantially lower educational attainment and occupational status than cohorts born shortly before or after. Several alternative explanations for this new finding are put to test. Most likely, a short but severe spell of quantitative and qualitative malnutrition immediately around the end of the war has impaired intrauterine conditions in first trimester pregnancies and resulted in longterm detriments among the affected cohorts. This conjecture is corroborated by evidence from Austria
Association between maternal nutritional status in pregnancy and offspring cognitive function in childhood and adolescence; a systematic review
Background
The mother is the only source of nutrition for fetal growth including brain development. Maternal nutritional status (anthropometry, macro- and micro-nutrients) before and/or during pregnancy is therefore a potential predictor of offspring cognitive function. The relationship of maternal nutrition to offspring cognitive function is unclear. This review aims to assess existing evidence linking maternal nutritional status with offspring cognitive function.
Methods
Exposures considered were maternal BMI, height and weight, micronutrient status (vitamins D, B12, folate and iron) and macronutrient intakes (carbohydrate, protein and fat). The outcome was any measure of cognitive function in children aged <18 years. We considered observational studies and trials with allocation groups that differed by single nutrients. We searched Medline/PubMed and the Cochrane Library databases and reference lists of retrieved literature. Two reviewers independently extracted data from relevant articles. We used methods recommended by the Centre for Reviews and Dissemination, University of York and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.
Results
Of 16,143 articles identified, 38 met inclusion criteria. Most studies were observational, and from high-income settings. There were few randomized controlled trials. There was consistent evidence linking maternal obesity with lower cognitive function in children; low maternal BMI has been inadequately studied. Among three studies of maternal vitamin D status, two showed lower cognitive function in children of deficient mothers. One trial of folic acid supplementation showed no effects on the childrenâs cognitive function and evidence from 13 observational studies was mixed. Among seven studies of maternal vitamin B12 status, most showed no association, though two studies in highly deficient populations suggested a possible effect. Four out of six observational studies and two trials (including one in an Iron deficient population) found no association of maternal iron status with offspring cognitive function. One trial of maternal carbohydrate/protein supplementation showed no effects on offspring cognitive function.
Conclusions
Current evidence that maternal nutritional status during pregnancy as defined by BMI, single micronutrient studies, or macronutrient intakes influences offspring cognitive function is inconclusive. There is a need for more trials especially in populations with high rates of maternal undernutrition.
Systematic review registration
Registered in PROSPERO CRD42013005702
Optimization of the Antitumor Activity of Sequence-specific Pyrrolobenzodiazepine Derivatives Based on their Affinity for ABC Transporters
Pyrrolobenzodiazepine (PBD) derivatives are highly potent sequence-specific DNA cross-linking agents. The present study aimed to identify key physicochemical properties influencing the interaction of a series of PBDs (four dimers and 12 monomers) with the three major human ATP-binding cassette (ABC) transporters (P-gp, ABCG2, and MRP1). Isogenic cell lines expressing P-gp and ABCG2, cell lines with acquired resistance to cytotoxic agents due to the high expression of ABC transporters, and specific inhibitors against P-gp, ABCG2, and MRP1 were used. P-gp and ABCG2 decreased the permeability of the PBD dimers across cell membranes and their interaction with DNA, reducing DNA damage and the overall cytotoxic effect. PBD monomer SG-2823 formed a conjugate with glutathione and interacted with MRP1, reducing its cytotoxic effect in A549 cells. Structureâactivity relationship revealed that the interaction of PBDs with the transporters could be predicted considering the molecular weight, the lipophilicity, the number of (Nâ+âO) atoms and aromatic rings, the polar surface area, the hydrogen bonding energy, and electrophilic centers. A rational design of novel PBDs with increased potency and reduced interaction with the ABC transporters is proposed
- âŠ