Study of tocopherol content and its potential antioxidant activity in commercial lipid emulsions for parenteral nutrition.

The objective of this study was to determine the content and evaluate the potential antioxidant effect of tocopherols in commercially available lipid emulsions, using a simple validated method adequate for further routine use. During the study, variability between manufacturers as well as between three non-consecutive batches of the same emulsion was observed. Furthermore, addition of α-tocopherol to lipid emulsions as excipient yields more stable emulsions and potentially a beneficial clinical effect. It was concluded that the variation of the tocopherol content between batches implies the importance of control and specification of tocopherol content by the manufacturers.

p53 gene discriminates two ecologically divergent sister species of pine voles.

Genes with relevant roles in the differentiation of closely-related species are likely to have diverged simultaneously with the species and more accurately reproduce the species tree. The Lusitanian (Microtus lusitanicus) and Mediterranean (M. duodecimcostatus) pine voles are two recently separated sister species with fossorial lifestyles whose different ecological, physiological and morphological phenotypes reflect the better adaptation of M. duodecimcostatus to the underground habitat. Here we asked whether the differentiation of M. lusitanicus and M. duodecimcostatus involved genetic variations within the tumour suppressor p53 gene, given its role in stress-associated responses. We performed a population-genetic analysis through sequencing of exons and introns of p53 in individuals from sympatric and allopatric populations of both the species in the Iberian Peninsula in which a unidirectional introgression of mitochondrial DNA was previously observed. We were able to discriminate the two species to a large extent. We show that M. duodecimcostatus is composed of one genetically unstructured group of populations sharing a P53 protein that carries a mutation in the DNA-binding region not observed in M. lusitanicus, raising the possibility that this mutation may have been central in the evolutionary history of M. duodecimcostatus. Our results provide suggestive evidence for the involvement of a master transcription factor in the separation of M. lusitanicus and M. duodecimcostatus during Microtus radiation in the Quaternary presumably via a differential adaptive role of the novel p53 in M. duodecimcostatus.

Impact of physical parameters on particle size and reaction yield when using the ionic gelation method to obtain cationic polymeric chitosan-tripolyphosphate nanoparticles.

Ionic gelation is the most frequently used method to obtain chitosan-tripolyphosphate nanoparticles due to its simplicity and because it does not generate waste solvents in the samples prepared. This paper presents a study of the physical factors involved in this method for obtaining nanoparticles in order to determine which of them significantly influences the particle size of polymeric nanoparticles made from low-molecular-weight chitosan, without any additional chemical treatment, with the aim of standardising and optimising the method conditions, in addition to establishing the reaction yield. The results indicate that stirring speed during ionic gelation reaction is decisive for the size of the nanoparticles obtained. Furthermore, it thus follows that the stirring speed during ionic gelation significantly affects reaction yield, and therefore, by manipulating this parameter a greater proportion of nanoparticles of a given size range can be obtained.

Method for the development of topical medicinal aerosols using liquified hydrocarbon gas.

Low chain liquid hydrocarbons (LH) at room temperature and atmospheric pressure can be used to simulate the effect of gas hydrocarbons (GH) in aerosol systems without the need of using pressured flasks. Samples of different tetracycline formulations were tested with LH and GH in order to study their behaviour and physicochemical stability in the system. The results showed a similar behaviour between samples when LH or GH were used, suggesting the use of LH to simulate the effect of GH introduction in the system, as a useful predictive method for the development of pressured aerosol formulations without using pressured containers in early steps of the process, such as pre-formulation studies.

[Nodular antritis and Helicobacter pylori infection in children]. / Antritis nodular e infección por Helicobacter pylori en el niño.

We have studied 115 patients infected with Helicobacter pylori (HP). Endoscopic nodular antritis and histologic lymphonodular hyperplasia was noted. The frequency of nodular antritis was compared between the 115 HP patients and a HP-negative age-matched control group. Nodular antritis was observed in 70.4% of the HP-positive patients and 11.3% of the HP-negative group (p <0.001). The specificity of nodular antritis was 86.1%. A significant association was found between the existence of nodular antritis and histologic lymphonodular hyperplasia (67.9%; p < 0.001). In conclusion, the endoscopic nodular antritis is a frequent and specific finding in children with HP infection and is associated with histologic lymphonodular hyperplasia.

[Histological lesions and Helicobacter pylori colonization in children]. / Lesión histológica y colonización por Helicobacter pylori en el niño.

We have assessed the relationship between histologic findings and the Helicobacter pylori (HP) colonization in 115 patients (age: 9.8 +/- 3.5 years) with HP infection. Normal antral histology was found in 8.7% of the patients. Signs of histological activity were observed in 58.2% of the patients and glandular lesions in 3.5%. A significantly greater HP colonization was observed in patients with signs of histological activity (p < 0.001). A significant correlation was found between the HP colonization score and histological score (rs = 0.62) with a significant association between the degree of HP colonization and the histologic categories (p < 0.001).