Increased risk for metachronous gastric adenocarcinoma following gastric MALT lymphoma-A US population-based study

Gastric mucosa-associated lymphoid tissue lymphoma (gMALT) and gastric adenocarcinoma (GC) are long-term complications of chronic Helicobacter pylori (HP) gastritis. Treatment of HP infection induces remission in most patients with gMALT. Endoscopic follow-up is not currently endorsed after complete remission. However, the risk of GC in these patients is unclear. OBJECTIVE: The objective of this study is to estimate GC risk in gMALT patients. METHODS: The National Cancer Institute Surveillance, Epidemiology and End Results 13 (SEER) database-Nov 2014 Sub (1992-2012) was used to identify adult patients diagnosed with gMALT between 1992 and 2012. The standardized incidence ratio of second primary GC after a latency period of 12 months was calculated and compared to a reference SEER cohort of identical age, sex and time period. The risk of GC in these patients was also stratified by latency period (five years) and age. RESULTS: We identified 2195 cases of gMALT lymphoma, and 20 (0.91%) of them subsequently developed GC with a relative risk (RR) of 4.32 (95% CI 2.64-6.67) compared to the American population. The median latency time was five years and the risk was maintained afterward (RR 4.92, 95% CI 2.45-8.79). When stratified by age group the risk was highest for the 45-64 group (RR 14.04, 95% CI 5.64-28.93). CONCLUSION: gMALT lymphoma is associated with an increased risk of metachronous gastric adenocarcinoma. The risk is still present after more than five years of follow-up. Further studies may clarify the most adequate follow-up strategy.info:eu-repo/semantics/publishedVersio

Quantum dynamics in strong fluctuating fields

A large number of multifaceted quantum transport processes in molecular systems and physical nanosystems can be treated in terms of quantum relaxation processes which couple to one or several fluctuating environments. A thermal equilibrium environment can conveniently be modelled by a thermal bath of harmonic oscillators. An archetype situation provides a two-state dissipative quantum dynamics, commonly known under the label of a spin-boson dynamics. An interesting and nontrivial physical situation emerges, however, when the quantum dynamics evolves far away from thermal equilibrium. This occurs, for example, when a charge transferring medium possesses nonequilibrium degrees of freedom, or when a strong time-dependent control field is applied externally. Accordingly, certain parameters of underlying quantum subsystem acquire stochastic character. Herein, we review the general theoretical framework which is based on the method of projector operators, yielding the quantum master equations for systems that are exposed to strong external fields. This allows one to investigate on a common basis the influence of nonequilibrium fluctuations and periodic electrical fields on quantum transport processes. Most importantly, such strong fluctuating fields induce a whole variety of nonlinear and nonequilibrium phenomena. A characteristic feature of such dynamics is the absence of thermal (quantum) detailed balance.Comment: review article, Advances in Physics (2005), in pres

Effect of salinity on the biosynthesis of n-3 long-chain polyunsaturated fatty acids in silverside Chirostoma estor

The genus Chirostoma (silversides) belongs to the family Atherinopsidae, which contains around 150 species, most of which are marine. However, Mexican silverside (Chirostoma estor) is one of the few representatives of freshwater atherinopsids and is only found in some lakes of the Mexican Central Plateau. However, studies have shown that C. estor has improved survival, growth and development when cultured in water conditions with increased salinity. In addition, C. estor displays an unusual fatty acid composition for a freshwater fish with high docosahexaenoic acid (DHA) : eicosapentaenoic acid (EPA) ratios. Freshwater and marine fish species display very different essential fatty acid metabolism and requirements and so the present study investigated long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis to determine the capacity of C. estor for endogenous production of EPA and DHA, and the effect that salinity has on these pathways. Briefly, C. estor were maintained at three salinities (0, 5 and 15 ppt) and the metabolism of 14C-labelled 18:3n-3 determined in isolated hepatocyte and enterocyte cells. The results showed that C. estor has the capacity for endogenous biosynthesis of LC-PUFA from 18-carbon fatty acid precursors, but that the pathway was essentially only active in saline conditions with virtually no activity in cells isolated from fish grown in freshwater. The activity of the LCPUFA biosynthesis pathway was also higher in cells isolated from fish at 15 ppt compared to fish at 5 ppt, The pathway was around 5-fold higher in hepatocytes compared to enterocytes, although the majority of 18:3n-3 was converted to 18:4n-3 and 20:4n-3 in hepatocytes whereas the proportions of 18:3n-3 converted to EPA and DHA were higher in enterocytes. The data were consistent with the hypothesis that conversion of EPA to DHA could contribute, at least in part, to the generally high DHA:EPA ratios observed in the tissue lipids of C. estor

A Small Mammal Community in a Forest Fragment, Vegetation Corridor and Coffee Matrix System in the Brazilian Atlantic Forest

The objective of our work was to verify the value of the vegetation corridor in the conservation of small mammals in fragmented tropical landscapes, using a model system in the southeastern Minas Gerais. We evaluated and compared the composition and structure of small mammals in a vegetation corridor, forest fragments and a coffee matrix. A total of 15 species were recorded, and the highest species richness was observed in the vegetation corridor (13 species), followed by the forest fragments (10) and the coffee matrix (6). The absolute abundance was similar between the vegetation corridor and fragments (F = 22.94; p = 0.064), and the greatest differences occurred between the vegetation corridor and the matrix (F = 22.94; p = 0.001) and the forest fragments and the matrix (F = 22.94; p = 0.007). Six species showed significant habitat preference possibly related to the sensitivity of the species to the forest disturbance. Marmosops incanus was the species most sensitive to disturbance; Akodon montensis, Cerradomys subflavus, Gracilinanus microtarsus and Rhipidomys sp. displayed little sensitivity to disturbance, with a high relative abundance in the vegetation corridor. Calomys sp. was the species least affected by habitat disturbance, displaying a high relative abundance in the coffee matrix. Although the vegetation corridors are narrow (4 m width), our results support the hypothesis in which they work as a forest extension, share most species with the forest fragment and support species richness and abundance closer to forest fragments than to the coffee matrix. Our work highlights the importance and cost-effectiveness of these corridors to biodiversity management in the fragmented Atlantic Forest landscapes and at the regional level