XANES study of iron displacement in the haem of myoglobin

The XANES (X-ray absorption near edge structure) spectra of deoxy human adult haemoglobin (HbA) and myoglobin (Mb) have been measured at the wiggler beam line of the Frascati synchrotron radiation facility. The XANES are interpreted by the multiple scattering cluster theory. The variations in the XANES between HbA and Mb are assigned to changes in the Fe-porphyrin geometry.     

Emerging role of tumor-associated macrophages as therapeutic targets in patients with metastatic renal cell carcinoma

Tumor-associated macrophages (TAMs) derived from peripheral blood monocytes recruited into the renal cell carcinoma (RCC) microenvironment. In response to inflammatory stimuli, macrophages undergo M1 (classical) or M2 (alternative) activation. M1 cells produce high levels of inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-12, IL-23 and IL-6, while M2 cells produce anti-inflammatory cytokines, such as IL-10, thus contributing to RCC-related immune dysfunction. The presence of extensive TAM infiltration in RCC microenvironment contributes to cancer progression and metastasis by stimulating angiogenesis, tumor growth, and cellular migration and invasion. Moreover, TAMs are involved in epithelial–mesenchymal transition of RCC cancer cells and in the development of tumor resistance to targeted agents. Interestingly, macrophage autophagy seems to play an important role in RCC. Based on this scenario, TAMs represent a promising and effective target for cancer therapy in RCC. Several strategies have been proposed to suppress TAM recruitment, to deplete their number, to switch M2 TAMs into antitumor M1 phenotype and to inhibit TAM-associated molecules. In this review, we summarize current data on the essential role of TAMs in RCC angiogenesis, invasion, impaired anti-tumor immune response and development of drug resistance, thus describing the emerging TAM-centered therapies for RCC patients.     

Hyperthermia triggers apoptosis and affects cell adhesiveness in human neuroblastoma cells

Hyperthermia is a known apoptotic inducer and has been recently utilized in combination with chemo-and/or radiotherapy in cancer treatment. In this study we have described its effect on SK-N-MC human neuroblastoma tumor cells, a line which grows as a double adherent and floating population. Considering this particular culture behavior, we also investigated the relationship between hyperthermia and cell adhesiveness by evaluating integrin expression, namely CD11a, which is, as known, closely correlated to cell adhesion properties. By a multiple, ultrastructural and flow cytometrical approach, we have demonstrated that hyperthermia, while triggering apoptosis, also determines a CD11a surface expression decrease in apoptotic and living cells. We thus suggest a further role for this treatment, which, affecting adhesion mechanisms, could down-regulate metastatic diffusion.     

Morphological and biochemical modifications induced by a static magnetic field on Fusarium culmorum

The effects of the exposure to a static magnetic field (sMF) of 0.3 +/- 0.03 T on the Fusarium culmorum were investigated in vitro. sMF inhibition of mycelia growth was accompanied by morphological and biochemical changes. Fungal conidia germination and cell viability were also reduced. We provide evidence of the influence of sMF on Ca(2+)-dependent signal transduction pathways involved in conidia germination. Perturbation of these pathways by adding different compounds (i.e. CaCl(2), phorbol 12-myristate 13-acetate, neomycin, EGTA, LiCl) to the medium, suggested that exposed conidia are unable to mobilise calcium from intracellular stores and that the hindered mechanism may be IP(3)-dependent.     

How physical exercise changes rat myotendinous junctions: an ultrastructural study

Myotendinous junctions can be easily injured by overloading or trauma, and exercise training may be a way of increasing their resistance to mechanical stress. To this end, we examined herein the morphological changes induced by moderate exercise training in the myotendinous junctions of extensor digitorum longus and gastrocnemius muscles in rats. Twelve Sprague-Dawley rats were used in this investigation. Six of them were trained to run on a treadmill for 1 h/day, 3 days/week over 10 weeks in order for them to achieve a running rate of 25 m/min at the end of the training period. Six age-matched sedentary rats were used as controls. The rats were sacrificed 24 h after the final training session, and the extensor digitorum longum (EDL) and the gastrocnemium were excised; the myotendinous junctions (MTJ) were then prepared and observed with electron microscopy. Digitation branching was evaluated by counting the bifurcations in the MTJ protrusions. Our observations indicate that exercise does indeed induce changes in MTJ morphology. In both muscles the number of bifurcated interdigitations increased significantly, as well as, in gastrocnemius, the branching of the finger-like processes. It was demonstrated that the MTJ is able to adapt to an increase in tensile force by enlarging the muscle-tendon contact area and, consequently, mechanical resistance.     

Partial persistence of exercise-induced myocardial angiogenesis following 4-week detraining in the rat

Enhanced angiogenesis, or capillary growth, has a prominent role among the various beneficial effects of exercise training on the myocardium. The aim of the present study is to assess if training-induced increases in capillarity and vascularization persist after 4 weeks of detraining. Adult male rats were trained to run on a treadmill for 10 weeks at ∼60% VO_2max, which did not induce cardiac hypertrophy, but increased (P < 0.05) the soleus/body weight ratio, left ventricle capillarity and von Willebrand-positive cell density (n = 6). In another group of animals (n = 6) subjected to training followed by 4-week detraining, the soleus/body weight ratio returned to normal, with only partial reversal of left ventricle capillarity and von Willebrand-positive cell density. Markers of angiogenesis (VEGF, KDR/VEGF-R2 and HIF-1α mRNA, studied by real-time RT-PCR) were upregulated at the end of training, and returned to baseline value after detraining. Electron microscopy highlighted some morphological features in trained hearts (endothelial cell sprouting and bridges and pericyte detachment), suggestive of endothelial cell proliferation and capillary growth that were absent in untrained and detrained hearts. We conclude that the training-induced increase in cardiac capillarity and vascularization are retained for some time upon cessation of the training program even in the absence of angiogenic stimuli.     

Oxygen bonding in human hemoglobin and its isolated subunits: a XANES study

The X-ray absorption near edge structure (XANES) spectra of the human adult and foetal hemoglobin, of the isolated alpha and beta chains, in the oxygenated forms, and of the oxymyoglobin and carp oxyhemoglobin have been measured at the wiggler beam line of the Frascati Synchrotron radiation facility. The bonding angle of oxygen molecule at the iron site in these hemoproteins in solution, has been measured using the multiple scattering theory for data analysis.     

Bacteria-produced ferric exopolysaccharide nanoparticles as iron delivery system for truffles (Tuber borchii)

Applied Microbiology and Biotechnology - Iron exopolysaccharide nanoparticles were biogenerated during ferric citrate fermentation by Klebsiella oxytoca DSM 29614. Before investigating their...     

Risk of symptomatic dengue for foreign visitors to the 2014 FIFA World Cup in Brazil

Brazil will host the FIFA World Cup™, the biggest single-event competition in the world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated 600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the 2014 event are theoretically at risk for dengue. We calculated the risk of dengue acquisition to non-immune international travellers to Brazil, depending on the football match schedules, considering locations and dates of such matches for June and July 2014. We estimated the average per-capita risk and expected number of dengue cases for each host-city and each game schedule chosen based on reported dengue cases to the Brazilian Ministry of Health for the period between 2010-2013. On the average, the expected number of cases among the 600,000 foreigner tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not only benefit individual travellers for adequate pre-travel preparations, but also provide valuable information for public health professionals and policy makers worldwide. Furthermore, estimates of dengue cases in international travellers during the World Cup can help to anticipate the theoretical risk for exportation of dengue into currently non-infected areas.