Background: The heat shock response of Arabidopsis thaliana is dependent upon a complex regulatory network involving twenty-one known transcription factors and four heat shock protein families. It is known that heat shock proteins (Hsps) and transcription factors (Hsfs) are involved in cellular response to various forms of stress besides heat. However, the role of Hsps and Hsfs under cold and non-thermal stress conditions is not well understood, and it is unclear which types of stress interact least and most strongly with Hsp and Hsf response pathways. To address this issue, we have analyzed transcriptional response profiles of Arabidopsis Hsfs and Hsps to a range of abiotic and biotic stress treatments (heat, cold, osmotic stress, salt, drought, genotoxic stress, ultraviolet light, oxidative stress, wounding, and pathogen infection) in both above and belowground plant tissues.

A simulation-based ML curriculum decreased operative time, improved trainee performance, and decreased intra- and postoperative complications and overnight stays after laparoscopic TEP inguinal hernia repair. ClinicalTrials.gov Identifier: NCT01085500.

Seasonal change in the intensity of fish predation affects succession in lake zooplankton communities. Predation affects not only the zooplankton prey, but also their parasites. Because the ability of a parasite to spread depends in part on the death rate of the hosts, seasonal reductions in the intensity of predation on zooplankton could lead to parasite epidemics. We examined seasonal population dynamics, mortality rate, and incidence of parasitism in lake populations of Daphnia to determine whether parasitism displayed seasonality and synchrony among lake populations and whether any such patterns are consistent with seasonal changes in predation rates. Infections of a bacterial parasite (Spirobacillus cienkowskii) in Daphnia dentifera populations were seasonal with epidemics in many lakes occurring synchronously in autumn. In situ foraging behavior of the dominant fish planktivores, bluegill sunfish, is highly selective on infected Daphnia. Mortality rates on the Daphnia drop just prior to the initiation of epidemics. An epidemiological model shows that this magnitude of decrease in mortality rate, if driven largely by a reduction in predation, can account for the seasonal occurrence of epidemics in our Daphnia populations. Together, these results suggest that parasitism in Daphnia populations may be seasonally restricted by fish predation.Historically, ecologists studying food webs regarded parasites as add-ons (Marcogliese and Cone 1997), while ecologists studying parasitism focused on the isolated interactions of hosts and parasites. Yet the ability of a parasite to spread and persist in a host population depends critically on the other members of the community (e.g., competitors and predators;Packer et al. 2003).

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Background-Mitral valve (MV) repair is preferred over replacement in clinical guidelines and is an important determinant of the indication for surgery in degenerative mitral regurgitation (MR). Yet, the level of evidence supporting current recommendations is low, and recent data cast doubts on its validity in the current era. Accordingly, the aim of the present study was to analyze very long-term outcome after MV repair and replacement for degenerative MR with a flail leaflet. Methods-MIDA is a multicenter registry enrolling patients with degenerative MR with a flail leaflet in 6 tertiary European and US centers. We analyzed the outcome after MV repair (n=1,709) and replacement (n= 213), overall, by propensity score matching and by inverse probability-of-treatment weighting. Results-At baseline, patients undergoing MV repair were younger, had more comorbidities and were more likely to present with a posterior leaflet prolapse than those undergoing MV replacement. After propensity score matching as well as after inverse probability-of-treatment weighting, the 2 treatments groups were balanced and absolute standardized differences were usually below 10%, indicating adequate match. Operative mortality (defined as a death occurring within 30 days from surgery or during the same hospitalization) was lower after MV repair than after replacement, both in the entire (1.3 vs 4.7%; p<0.001) and in propensity-matched population (0.2% vs 4.4%; p<0.001). During a mean follow-up of 9.2 years, 552 deaths were observed, of which 207 were of cardiovascular origin. Twenty-year survival was better after MV repair than after MV replacement, both in the entire (46% vs 23%, p<0.001) and in matched population (41% vs 24%, p<0.001). Similar superiority of MV repair were obtained in patients' subsets based on age, sex or any stratification criteria (all p<0.001). MV repair was also associated with reduced incidence of reoperations and valve-related complications.Conclusions-Among patients with degenerative MR with a flail leaflet, referred to mitral surgery, MV repair was associated with lower operative mortality, better long-term survival and fewer valve-related complications compared to MV replacement.