Clinical and Metabolic Improvement after Bariatric Surgery in Older Adults: A 6-Year Follow-Up.

AIM: Our aim in this study was to assess the clinical and metabolic impact of bariatric surgery in older adults. METHODS: This analytical, observational, longitudinal study was carried out with individuals aged 60 years and older who underwent bariatric surgery after 55 years of age at a specialist center for obesity management located in the Federal District of Brazil. Post-surgery changes in the following parameters from baseline: total body weight, excess weight lost, body mass index (BMI), number of medications, number of comorbidities, and weight regain. Mean values of the variables of interest before and after surgery were compared using the nonparametric Wilcoxon test, Poisson regression and multiple linear regression to test the effect of different variables. RESULTS: Overall, 74 subjects were assessed (78.3% female, mean age 65.8 ± 3.9 years). The mean time from bariatric surgery to assessment was 75.7 months. The mean weight and BMI in the overall sample at baseline was 101.9 ± 17.1 kg and 39.8 ± 4.9 kg/m², respectively. After the procedure, mean weight and BMI were reduced to 75.9 ± 12.9 kg and 29.4 ± 4.1 kg/m², respectively. Reductions were also achieved in mean number of medications used (P<0.001), number of comorbidities (P<0.001), triglyceride levels (P=0.007), and glycated hemoglobin (P=0.02). The mean HDL level increased significantly (P=0.008). CONCLUSION: In this sample, bariatric surgery was not only useful to manage obesity, but also reduced the number of comorbidities and medications used, and was associated with improvement in clinical and laboratory parameters.

Importance of interplane coupling on the magnetic phases of quasi-two-dimensional tantalites.

We propose a three-dimensional model to describe magnetic interactions in a class of tantalite compounds of compositions A(x)A'(1-x)Ta(2)O(6), with A,A' = Fe, Co or Ni. Due to the quasi-two-dimensional nature of the magnetism in these compounds, experimental data have been previously interpreted using two-dimensional models. These are anisotropic Heisenberg models or Ising models and include competing exchange interactions from different neighbors. Taking into account all the relevant exchange terms, which include interplane interactions, we show that the latter allows us to understand the various low-temperature magnetic phases observed by neutron diffraction in this family of compounds. This is done by studying the eigenvalues of the exchange-interaction matrix in wavevector space for different sets of coupling parameters, of which those relative to in-plane interactions have been obtained from high-temperature series analysis of the magnetic susceptibility. This approach is rather general and the model presented here is directly applicable to isostructural compounds like ASb(2)O(6).

First detection of porcine norovirus GII.18 in Latin America.

Human (Hu) noroviruses (NoVs) circulate worldwide infecting people of all ages in developing and developed countries. Animal NoVs present some antigenic and genetic relationship to HuNoVs, although their zoonotic potential has not been established yet. Among animal NoVs, porcine (Po) NoVs are the most genetically related to HuNoVs. PoNoVs have only been detected in healthy finisher pigs in a few developed countries. Information about them lacks in developing countries. In this study 96 fecal samples from pigs of different ages from five farms in Rio de Janeiro State, Brazil were tested for NoVs. We report detection and genotyping by RT-PCR, nucleotide sequencing and phylogenetic analysis of partial polymerase and capsid regions of viral genome PoNoV genogroup II genotype 18 (GII.18) in one stool sample from a healthy finisher pig. This is the first report of PoNoV detection in Latin America and it supports the assumption that PoNoVs present a worldwide distribution.

Magnetic phases of the quasi-two-dimensional compounds FexCo1 - xTa2O6.

We report new results on the magnetic properties of the FexCo1 - xTa2O6 series of compounds. Essentially using neutron-diffraction and magnetic measurements we study, in more detail, the low-x limit of the temperature versus x phase diagram, where a new bicritical point is observed. The complete phase diagram shows three different magnetic phases at low temperature, for a high, intermediate and very low iron content. These phases consist of distinct antiferromagnetic orderings, characterized by different pairs of propagation vectors. We obtain information about the intraplane exchange interactions by fitting a high-temperature series of the magnetic susceptibility. Here we improve on a previously employed model, showing that two non-equivalent next-nearest-neighbor interactions must be taken into account in order to allow for in-plane magnetic orderings that are consistent with the neutron-diffraction results.

Bicriticality in FexCo1-xTa2O6.

X-ray and neutron-diffraction, dc magnetic susceptibility, magnetization, and specific-heat measurements are reported for FexCo(1-x)Ta2O6 mixed oxides. X-ray refinement indicates homogeneous samples for all the reported concentrations. The neutron-diffraction measurements reveal magnetic structures with double propagation vectors (+/-1/4,1/4,1/4) for CoTa2O6, and (1/2,0,1/2) and (0,1/2,1/2) for FeTa2O6. The latter remain unchanged in the Fe-rich samples, for 0.46< or =x<1.00, while the Co-rich samples show propagation vectors (+/-1/4,1/4,0) for 0.09< or =x<0.46. The temperature vs x phase diagram exhibits a bicritical point at about T=4.9 K and x=0.46. For this concentration, and at low temperatures, the system shows coexistence of both magnetic structures. This novel bicritical behavior is interpreted as induced by competition between the different magnetic and crystallographic structures.