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Purpose: Exposure to hypoxia has been suggested to activate multiple adaptive pathways so that muscles are better able to maintain cellular energy homeostasis. However, there is limited research regarding the tissue specificity of this response. The aim of this study was to investigate the influence of tissue specificity on mitochondrial adaptations of rat skeletal and heart muscles after 4 weeks of normobaric hypoxia (FiO2: 0.10). Methods: Twenty male Wistar rats were randomly assigned to either normobaric hypoxia or normoxia. Mitochondrial respiration was determined in permeabilised muscle fibres from left and right ventricles, soleus and extensorum digitorum longus (EDL). Citrate synthase activity and the relative abundance of proteins associated with mitochondrial biogenesis were also analysed. Results: After hypoxia exposure, only the soleus and left ventricle (both predominantly oxidative) presented a greater maximal mass-specific respiration (+48 and +25%, p < 0.05) and mitochondrial-specific respiration (+75 and +28%, p < 0.05). Citrate synthase activity was higher in the EDL (0.63 ± 0.08 vs 0.41 ± 0.10 µmol min− 1 µg− 1) and lower in the soleus (0.65 ± 0.17 vs 0.87 ± 0.20 µmol min− 1 µg− 1) in hypoxia with respect to normoxia. There was a lower relative protein abundance of PGC-1α (−25%, p < 0.05) in the right ventricle and a higher relative protein abundance of PGC-1β (+43%, p < 0.05) in the left ventricle of rats exposed to hypoxia, with few differences for protein abundance in the other muscles. Conclusion: Our results show a muscle-specific response to 4 weeks of normobaric hypoxia. Depending on fibre type, and the presence of ventricular hypertrophy, muscles respond differently to the same degree of environmental hypoxia

The aim of the study was to evaluate the impact of a 2-year vaccination program on the compliance of healthcare workers (HCWs) employed in an acute care university hospital to influenza vaccination. The study was carried out in October/November from 2004 to 2006 in a 286-bed acute care university hospital located in northern Italy employing 523 HCWs. The study cohort consisted of 473 HCWs continuously present in the hospital from 2004 to 2006. In 2005 and 2006, a vaccination campaign was made available in the wards that supplemented a pre-existing (2004) employee health service program. A personalized informative letter was sent to all HCWs explaining the risks and benefits of influenza vaccination for both patients and HCWs and indicating the scheduling of the additional vaccination service. The additional 2005 and 2006 campaigns produced significantly higher vaccination rates among HCWs than those achieved in previous years, from 10.4% in 2004 to 36.6% in 2005 and 23.2% in 2006. The year 2005 was characterized by an avian flu threat, which likely accounted for the highest vaccination rate of the 3-year study period. Physicians had the highest vaccination rates in the 3-year period (20.8%), while nurses in 2005 had the highest single vaccination rate (42.5%). Providing easy access to vaccination in the wards is a useful approach for improving vaccination rates among HCWs, but further tailored interventions are needed because overall vaccination rates remain too low. Subgroups, such as nurses and ancillary staff, should be considered as specific targets of such vaccination programs.