Exposición solar en la enfermedad inflamatoria intestinal ambulatoria: factores predictivos y correlación con la concentración sérica de vitamina D

IntroductionSunlight exposure is the main source of vitamin D. Our aim was to describe both sun exposure and sun protection behaviour in a series of patients with inflammatory bowel disease (IBD), and to study their potential association with vitamin D concentration.Patients and methodsA cross sectional, observational study. The clinical-demographic variables were obtained via clinical interviews and medical history review. The sunlight exposure assessment was carried out using the Sun Exposure Questionnaire and the concentration of 25-hydroxy vitamin D (25OHD) was measured by an electro-chemiluminescence immunoassay. Questionnaires were conducted on quality of life, physical activity, weekly vitamin D intake and sun protection behaviour.Results149 patients were included. In 69% of patients, deficient or insufficient 25OHD values were recorded. 67% showed low sun exposure. A modest significant correlation was observed between the total score of the solar exposure questionnaire and the 25OHD concentration in the complete series (r = 0.226, P = .006) and in the summer (r = 0.274, P = .01). The sun protection behaviour questionnaire score did not influence the 25OHD concentration. In the multivariate analysis, only the presence of clinical activity was associated with low sun exposure (OR = 3.23).DiscussionSun exposure according to the questionnaire used was low, was associated with the presence of clinical activity and was weakly correlated with serum 25OHD concentration. More studies are needed to explore the use of individual questionnaires for sun exposure and its relationship with vitamin D in patients with IBD.     

Proficiency tests for radionuclide laboratories supporting the network of IMS stations.

A tailored proficiency test programme in high-resolution gamma-spectrometric analysis has been established for the radionuclide laboratories designated to support the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). It entails certified reference samples that contain fission products relevant to the CTBT. The sample geometries and materials correspond to aerosol filter samples from the high-volume samplers of the radionuclide stations of the International Monitoring System (IMS) and the related calibration sources are matrix and geometry matched to the reference samples.     

Axillary web syndrome: Incidence,pathogenesis, and management

Axillary web syndrome (AWS) refers to the development of fibrotic bands or “cords” in the axilla of patients who have undergone axillary lymph node dissection for breast cancer. We review the incidence, pathogenesis, risk factors, and management of AWS. AWS is a common complication in patients who undergo axillary lymph node dissection. Even though AWS is self-limited in most cases, it causes significant morbidity. The optimal management of AWS is unclear but physiotherapy appears to be beneficial. The widespread use of less invasive procedures to evaluate the presence of metastasis in the axillary lymph nodes (ie, sentinel lymph node biopsy) is expected to reduce the incidence of AWS. The close collaboration of surgeons, oncologists, and physiotherapists is necessary for the prevention and management of this frequent condition.     

A homozygote TREX1 mutation in two siblings with different phenotypes: Chilblains and cerebral vasculitis

Three prime repair exonuclease 1 degrades single and double stranded DNA with 3′-5′ nuclease activity and its mutations are related to type 1 IFN mediated autoinflammation due to accumulated intracellular nucleic acids. To date, several cases of systemic lupus erythematosus, Aicardi-Goutieres syndrome, familial chilblain lupus, retinal vasculopathy-cerebral leukodystrophy have been reported with TREX1 mutations.Chilblain lupus is a skin disease characterized by blue-reddish coloring, swelling or ulcers on acral regions of body such as fingertips, heels, nose and auricles. Central nervous system vasculitis is a prominent cause of childhood strokes.10 families with familial chilblain lupus related to TREX1 mutations were reported previously in the literature, in which homozygote D18N variant in TREX1 gene was related to chilblains with cerebral vasculitis.In this report, whole-exome-sequencing revealed a homozygote R114C mutation in TREX1 gene was shown in two siblings with recurrent chilblains whom one of them was the second case accompanied by cerebral vasculitis in the literature. As a result, the approach of WES in clinical use revealed a novel mutation in clinically heterogenous patients to provide genetic counseling.     

Synthesis of controlled-size silver nanoparticles for the administration of methotrexate drug and its activity in colon and lung cancer cells

A controlled synthesis of methotrexate (MTX) silver nanoparticles (AgNPs-MTX) using borohydride and citrate as reduction and reduction/capping agents, respectively, was performed in order to obtain AgNPs-MTX conjugates with a narrow size distribution. Their characterization showed polydispersed spherical shape nanoparticles with a mean size around 13 nm and distribution range between 7–21 nm. The presence of MTX was confirmed by FTIR and EDX analysis. Spectroscopic determinations suggest the chemisorption of MTX through a carboxylic group (–COOH) onto AgNPs via the exchange with a citrate molecule. Drug loading capacities calculated for AgNPs synthesized using different amounts of MTX were 28, 31 and 40%. In vitro drug release tests depicted similar release profiles for all conjugated amounts releasing between 77 to 85% of the initial MTX loaded into the AgNPs. With respect to free MTX, the addition of the nanocarrier delayed its release and also changed its pharmacokinetics. Free MTX is released after 3 hours following a first order kinetic model, whereas in the presence of AgNPs, a fast initial release is observed during the first 5 hours, followed by a plateau after 24 hours. In this case, AgNPs-MTX fitted a Higuchi model, where its solubilization is controlled by a diffusion process. Results obtained from flow cytometry of different cell lines treated with AgNPs-MTX demonstrated the combined anticancer effect of both reagents, decreasing the percentage of living cells in a colon cancer cell line (HTC-116) down to 40% after 48 hours of exposure. This effect was weaker but still significant for a lung cancer cell line (A-549). Finally, a zebrafish assay with AgNPs-MTX did not show any significant cytotoxic effect, confirming thereby the reduction of systemic drug toxicity achieved by coupling MTX to AgNPs. This observed toxicity reduction in the zebrafish model implies also a probable improvement of the usage of AgNPs-MTX in chemotherapy against human cancers.

A controlled synthesis of methotrexate (MTX) silver nanoparticles (AgNPs-MTX) using borohydride and citrate as reduction and reduction/capping agents, respectively, was performed in order to obtain AgNPs-MTX conjugates with a narrow size distribution.     

Transesterification of a series of 12 parabens by liver and small-intestinal microsomes of rats and humans

Hydrolytic transformation of parabens (4-hydroxybenzoic acid esters; used as antibacterial agents) to 4-hydroxybenzoic acid and alcohols by tissue microsomes is well-known both in vitro and in vivo. Here, we investigated transesterification reactions of parabens catalyzed by rat and human microsomes, using a series of 12 parabens with C1–C12 alcohol side chains. Transesterification of parabens by rat liver and small-intestinal microsomes occurred in the presence of alcohols in the microsomal incubation mixture. Among the 12 parabens, propylparaben was most effectively transesterified by rat liver microsomes with methanol or ethanol, followed by butylparaben. Relatively low activity was observed with longer-side-chain parabens. In contrast, small-intestinal microsomes exhibited higher activity towards moderately long side-chain parabens, and showed the highest activity toward octylparaben. When parabens were incubated with liver or small-intestinal microsomes in the presence of C1–C12 alcohols, ethanol and decanol were most effectively transferred to parabens by rat liver microsomes and small-intestinal microsomes, respectively. Human liver and small-intestinal microsomes also exhibited significant transesterification activities with different substrate specificities, like rat microsomes. Carboxylesterase isoforms, CES1b and CES1c, and CES2, exhibited significant transesterification activity toward parabens, and showed similar substrate specificity to human liver and small-intestinal microsomes, respectively.