Every year about 3 million tourists from around the world visit Brazil, Argentina and Paraguay´s triple border region where the Iguaçu Falls are located. Unfortunately, in recent years an increasing number of autochthonous canine and human visceral leishmaniasis (VL) cases have been reported. The parasite is Leishmania (Leishmania) infantum and it is transmitted by sand flies (Phlebotominae). To assess the risk factors favorable for the establishment and spread of potential vectors the Centers for Disease Control and Prevention light trap (CDC-light trap) collections were made in the Foz do Iguaçu (FI) and Santa Terezinha de Itaipu (STI) townships and along two transects between them. Our study determined the Phlebotominae fauna, the factors that affect the presence and abundance of Lutzomyia longipalpis and Nyssomyia whitmani, the presence of L. infantum in different sand fly species and which Leishmania species are present in this region. Lutzomyia longipalpis was the prevalent species and its distribution was related to the abundance of dogs. Leishmania infantum was found in Lu. longipalpis, Ny. whitmani, Ny. neivai and a Lutzomyia sp. All the results are discussed within the Stockholm Paradigm and focus on their importance in the elaboration of public health policies in international border areas. This region has all the properties of stable VL endemic foci that can serve as a source of the disease for neighboring municipalities, states and countries. Most of the urban areas of tropical America are propitious for Lu. longipalpis establishment and have large dog populations. Pan American Health Organization´s initiative in supporting the public health policies in the border areas of this study is crucial and laudable. However, if stakeholders do not act quickly in controlling VL in this region, the scenario will inevitable become worse. Moreover, L. (Viannia) braziliensis found in this study supports the need to develop public health policies to avoid the spread of cutaneous leishmaniasis. The consequences of socioeconomic attributes, boundaries and frontiers on the spread of diseases cannot be neglected. For an efficient control, it is essential that urban planning is articulated with the neighboring cities.

Carbohydrate metabolism and the antioxidant defence system of heart and muscle of the Antarctic notothenioids Notothenia rossii and Notothenia coriiceps were evaluated in response to heat stress (8 °C) over 144 h. N. rossii heart exhibited decreased glycolysis and aerobic metabolism after up to 12 h of exposure to 8 °C, and anaerobiosis was inhibited within 24 h. However, these pathways were stimulated after 72 h at 8 °C. The consumption of glucose-6-phosphate, derived from hexokinase (HK), by glucose-6-phosphate dehydrogenase (G6PDH) decreased in N. rossii heart within 6 h at 8 °C, with a subsequent increase at 72 h. In N. rossii muscle at 8 °C, glycolysis was stimulated within 2 h by an increase in pyruvate kinase (PK), and aerobic metabolism was stimulated at 144 h, together with anaerobiosis. In N. coriiceps heart at 8 °C, glucose break down by HK decreased within 2 h and subsequently increased at 12 and 24 h. Increased glucose-6-phosphate consumption by G6PDH occurred within 6 h at 8 °C. In N. coriiceps muscle at 8 °C, glycolysis was stimulated at 2 and 6 h, with subsequent inhibition within 24 h, as indicated by HK activity. Aerobic metabolism was inhibited at 72 and 144 h at 8 °C through the inhibition of citrate synthase (CS). Heat stress caused responses were only occasional and transient in antioxidant defence system of both species in the heart and muscle, leading to increased glutathione (GSH) and decreased levels of lipoperoxidation in the heart of both species. The results obtained in this study in the heart and muscles indicate that under heat stress at 8 °C, N. rossii is more responsive than N. coriiceps with respect to carbohydrate metabolism.

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Proteomic analysis of gill tissue in Antarctic limpets exposed to different concentrations of lead (Pb) over a 168 h time period showed that proteomic changes vary with time. These changes included an increase in the demand of scavenging reactive oxygen species, acid-base balance and a challenge to protein homeostasis in the endoplasmic reticulum early on and subsequently an increase in energy metabolism, cellular signaling, and cytoskeletal modifications. Based on this time course, we hypothesize that the main mode of action of lead is a replacement of metal-cofactors of key enzymes involved in the scavenging of reactive oxygen species and the regulation of acid-base balance.

The heavy metal cadmium (Cd) is known to modulate the immune system, challenging soil-dwelling organisms where environmental Cd pollution is high. Since earthworms lack adaptive immunity, we determined Cd-related effects on coelomocytes, the cellular part of innate immunity, which is also the site of detoxification processes. A proteomics approach revealed a set of immunity-related proteins as well as gene products involved in energy metabolism changing in earthworms in response to Cd exposure. Based on these results, we conducted extracellular flux measurements of oxygen and acidification to reveal the effect of Cd on coelomocyte metabolism. We observed a significantly changing oxygen consumption rate, extracellular acidification, as well as metabolic potential, which can be defined as the response to an induced energy demand. Acute changes in intracellular calcium levels were also observed, indicating impaired coelomocyte activation. Lysosomes, the cell protein recycling center, and mitochondrial parameters did not change. Taken together, we were able to characterize coelomocyte metabolism to reveal a potential link to an impaired immune system upon Cd exposure.

e Antarctic continent is considered one of the most well preserved areas of the planet

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Ecological impacts of climate change on marine environments have been signi cant in the Antarctic Peninsula. Ecological responses may a ect sh fauna from the species level to community level. Our goal was to analyze histological and histochemical aspects of three stomach portions (cardiac, fundic and pyloric) of Notothenia rossii, an antarctic sh, under thermal stress using light microscopy. Fish were collected in Admiralty Bay and taken to the Brazilian Antarctic station "Comandante Ferraz". Fish (n=5/bioassay) were acclimated in seawater tanks (0ºC/35‰) and exposed to temperatures of 0°C (control), 4°C and 8°C during 1, 4, 15 and 30 days. Samples were processed and stained with haematoxylin/eosin, Periodic Schi acid, Alcian-Blue pH 2.5 and 1.5. Heating caused an increase in the muscle layer of fundic and pyloric regions in samples kept for 1 day at 8°C and 4 days at 4°C, compared with the control group. Expression of neutral glycosaminoglycans was not a ected by increasing temperature. ermal stress caused a reduction in expression of carboxylated and sulfated-glycosaminoglycans in samples kept at 8°C during 1, 4 and 30 days. However, the stomach does not show histological and histochemical standard alterations under di erent thermal stress conditions and, therefore, we cannot be conclusive about the lack of full functionality.