Small-angle X-ray scattering to quantify the incorporation and analyze the disposition of magnetic nanoparticles inside cells.

Access to detailed information on cells loaded with nanoparticles with nanoscale precision is of a long-standing interest in many areas of nanomedicine. In this context, designing a single experiment able to provide statistical mean data from a large number of living unsectioned cells concerning information on the nanoparticle size and aggregation inside cell endosomes and accurate nanoparticle cell up-take is of paramount importance. Small-angle X-ray scattering (SAXS) is presented here as a tool to achieve such relevant data. Experiments were carried out in cultures of B16F0 murine melanoma and A549 human lung adenocarcinoma cell lines loaded with various iron oxide nanostructures displaying distinctive structural characteristics. Five systems of water-dispersible magnetic nanoparticles (MNP) of different size, polydispersity and morphology were analyzed, namely, nearly monodisperse MNP with 11 and 13 nm mean size coated with meso-2,3-dimercaptosuccinic acid, more polydisperse 6 nm colloids coated with citric acid and two nanoflowers (NF) systems of 24 and 27 nm in size resulting from the aggregation of 8 nm MNP. Up-take was determined for each system using B16F0 cells. Here we show that SAXS pattern provides high resolution information on nanoparticles disposition inside endosomes of the cytoplasm through the structure factor analysis, on nanoparticles size and dispersity after their incorporation by the cell and on up-take quantification from the extrapolation of the intensity in absolute scale to null scattering vector. We also report on the cell culture preparation to reach sensitivity for the observation of MNP inside cell endosomes using high brightness SAXS synchrotron source. Our results show that SAXS can become a valuable tool for analyzing MNP in cells and tissues.

[Influence of initial protocolized treatment with steroids in length of stay and costs of community acquired pneumonia]. / Influencia de la protocolización del tratamiento inicial con corticoides en la estancia y costo de las neumonías adquiridas en la comunidad. Estudio prospectivo 2015.

OBJECTIVE: The aim of the study was to analyze the impact of steroid treatment in patients with community acquired pneumonia (CAP), both in length of stay and economical cost of admission at a clinical university hospital. METHODS: Prospective study of admitted patients with the diagnosis of CAP, both in Internal Medicine and Infectious diseases department. The study was conducted from January to march 2015; patients receiving steroids from diagnosis to end of antibiotic treatment were classified as group I; otherwise, they were considered in group II. Administration of steroids was done according to the criteria of the responsible. Cost was stablished according to CAP Diagnostic Related Group (DRG). RESULTS: Prevalence of patients younger than 65 year-old was higher in group I (p<0.05). In bivariate analyses, mean admission time was lower in group I (5.37 vs 8.88 days) (p<0.0005) and also economical cost (2,361 euros vs 3,907 euros) (p<0.0005). In multivariate analysis, factors independently associated to higher cost (>3,520 euros) were COPD (OR=2.602; 95% CI 1.074-6.305) and group II (patients with no steroids) (OR=6.2; p=0,007). CONCLUSIONS: No administration of steroids in patients with CAP was associated, together with COPD, with higher economical cost (evaluated by DRG/length of stay).

Exposures and cancer incidence near oil fields in the Amazon basin of Ecuador.

OBJECTIVES: To examine environmental exposure and incidence and mortality of cancer in the village of San Carlos surrounded by oil fields in the Amazon basin of Ecuador. METHODS: Water samples of the local streams were analyzed for total petroleum hydrocarbons (TPHs). A preliminary list of potential cancer cases from 1989 to 1998 was prepared. Cases were compared with expected numbers of cancer morbidity and mortality registrations from a Quito reference population. RESULTS: Water analysis showed severe exposure to TPHs by the residents. Ten patients with cancer were diagnosed while resident in the village of San Carlos. An overall excess for all types of cancer was found in the male population (8 observed v 3.5 expected) with a risk 2.26 times higher than expected (95% confidence interval (95% CI) 0.97 to 4.46). There was an overall excess of deaths for all types of cancer (6 v 1.6 expected) among the male population 3.6 times higher than the reference population (95% CI 1.31 to 7.81). CONCLUSIONS: The observed excess of cancer might be associated with the pollution of the environment by toxic contaminants coming from the oil production.

Clinical parameters (body mass index and age) are the best predictors for the need of insulin therapy during the first 18 months of diabetes mellitus in young adult patients.

To address the question whether there are simple clinical predictors of need for insulin in the first 18 months of treatment of diabetes presenting in young adult subjects, a prospective study of 24 patients with diabetes mellitus (age: 18-40 years) was designed. At diagnosis of diabetes, age, sex, body mass index (BMI), glycemia, ketonuria, C-peptide, insulin autoantibodies, islet cell antibodies and glutamic acid decarboxylase antibodies were recorded before starting any treatment. At the end of the follow-up (18 +/- 4 months), they were divided into two groups according to their need for insulin therapy: group 1 (n=15; 62%), who needed insulin therapy, and group 2 (n=9; 38%), who did not. Each marker was related to actual need for therapy necessity. Multivariate analysis showed that BMI and age were the variables with greatest predictive value regarding need for insulin. These data reveal that the need for insulin therapy in young adult diabetic patients may be supported by the clinical criteria of age and BMI, which are both easily and quickly determined.

Evolution and factors associated with biological-risk accidents reported in a university hospital in Spain, 1989 to 1995.

BACKGROUND: The objective of this study was to describe the profile and evolution of accidents involving risk of transmission of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) reported in a large Spanish hospital, together with the preventive measures administered and the factors associated with high-risk accidents. METHODS: Data used were the accidents recorded in the hospital during the period from January 1989 to December 1995. A logistic model, using age, gender, service, occupation, and year of accident as independent variables was constructed to study the factors associated with these accidents. RESULTS: The study included 1,009 accidents. Accidents were more common among nurses, female doctors, younger workers, and persons who worked in surgical settings. Of the total sources of infection studied, 11.6% were positive for HBV, 28.2% for HCV, and 24.4% for HIV. No seroconversions were detected in the partial follow-ups conducted. The factors associated with high-risk accidents were gender (relative risk [RR], 2.01; 95% confidence interval [CI95], 1.24-3.60); occupation as physician (RR, 2.57; CI95, 1.54-4.29) or as nursing staff (RR, 1.80; CI95, 1.12-2.89); and working in a surgical service (RR, 2.01; CI95, 1.27-3.18). Younger workers had more accidents overall, but older workers were more likely to have high-risk exposure. In the multivariate analysis, the occupation (physician and nursing staff) was the most important variable when adjusted by the other factors. CONCLUSIONS: Our results suggest that a greater effort still is required in the application and evaluation of preventive measures. New safety systems, with clearly proven cost-effectiveness, should be developed and applied.

[Medullary carcinoma of the thyroid gland. Prognostic factors]. / Carcinoma medular de tiroides. Factores pronósticos.

OBJECTIVE: To analyze the clinical features and possible prognostic factors involved in the clinical course of a series of 26 patients with the diagnosis of thyroid medullar carcinoma (TMC). MATERIALS AND METHODS: An analysis was made of the variables age, sex, clinical course to diagnosis, paraneoplastic manifestations (flush, diarrhoea), clinical type (sporadic, non-associated, familial MEN IIa associated TMC, familial MEN IIb associated TMC), histologic uni or multicentricity, and stage of disease as possible predictive factors for the evolution. RESULTS: The most remarkable prognostic factor was tumoral stage. The likelihood of a patient diagnosed with stage I or II being free of metastatic disease was 1, 0.66 and 0.33 at 15, 16 and 17 years, respectively. In contrast, those patients in stage III at diagnosis had a likelihood of being free from metastasis 5 years after diagnosis and therapy of 0. With regard to sex, a better clinical course was observed among males than among females, statistically significant at 3 and 5, but not at 10 years. No statistical significance was reached with the other possible prognostic factors investigated. CONCLUSION: Given the obvious influence of tumoral stage of disease on prognosis, an early access to medical attention is desirable for diagnosis and treatment of TMC, as well as an early detection of family cases by a screening test.