Survey of Sand Flies (Diptera: Psychodidae) in an Environmentally Protected Area in Brazil

Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL). Furthermore, with the geographical expansion of visceral leishmaniasis (VL), several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania) infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia) braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%), these data indicate the circulation of the parasite and reinforce the need for entomological and epidemiological surveillance in the park and its surroundings.     

Polymorphisms in the TNFA and IL6 Genes Represent Risk Factors for Autoimmune Thyroid Disease

Background

Autoimmune thyroid disease (AITD) comprises diseases including Hashimoto''s thyroiditis and Graves'' disease, both characterized by reactivity to autoantigens causing, respectively, inflammatory destruction and autoimmune stimulation of the thyroid-stimulating hormone receptor. AITD is the most common thyroid disease and the leading form of autoimmune disease in women. Cytokines are key regulators of the immune and inflammatory responses; therefore, genetic variants at cytokine-encoding genes are potential risk factors for AITD.

Methods

Polymorphisms in the IL6-174 G/C (rs1800795), TNFA-308 G/A (rs1800629), IL1B-511 C/T (rs16944), and IFNGR1-56 T/C (rs2234711) genes were assessed in a case-control study comprising 420 Hashimoto''s thyroiditis patients, 111 Graves'' disease patients and 735 unrelated controls from Portugal. Genetic variants were discriminated by real-time PCR using TaqMan SNP genotyping assays.

Results

A significant association was found between the allele A in TNFA-308 G/A and Hashimoto''s thyroiditis, both in the dominant (OR = 1.82, CI = 1.37–2.43, p-value = 4.4×10⁻⁵) and log-additive (OR = 1.64, CI = 1.28–2.10, p-value = 8.2×10⁻⁵) models. The allele C in IL6-174 G/C is also associated with Hashimoto''s thyroiditis, however, only retained significance after multiple testing correction in the log-additive model (OR = 1.28, CI = 1.06–1.54, p-value = 8.9×10⁻³). The group with Graves'' disease also registered a higher frequency of the allele A in TNFA-308 G/A compared with controls both in the dominant (OR = 1.85, CI = 1.19–2.87, p-value = 7.0×10⁻³) and log-additive (OR = 1.69, CI = 1.17–2.44, p-value = 6.6×10⁻³) models. The risk for Hashimoto''s thyroiditis and Graves'' disease increases with the number of risk alleles (OR for two risk alleles is, respectively, 2.27 and 2.59).

Conclusions

This study reports significant associations of genetic variants in TNFA and IL6 with the risk for AITD, highlighting the relevance of polymorphisms in inflammation-related genes in the etiopathogenesis of AITD.     

Sympathetic glial cells and macrophages develop different responses to Trypanosoma cruzi infection or lipopolysaccharide stimulation

Nitric oxide (NO) participates in neuronal lesions in the digestive form of Chagasdisease and the proximity of parasitised glial cells and neurons in damaged myentericganglia is a frequent finding. Glial cells have crucial roles in manyneuropathological situations and are potential sources of NO. Here, we investigateperipheral glial cell response to Trypanosoma cruzi infection toclarify the role of these cells in the neuronal lesion pathogenesis of Chagasdisease. We used primary glial cell cultures from superior cervical ganglion toinvestigate cell activation and NO production after T. cruziinfection or lipopolysaccharide (LPS) exposure in comparison to peritonealmacrophages. T. cruzi infection was greater in glial cells, despitesimilar levels of NO production in both cell types. Glial cells responded similarlyto T. cruzi and LPS, but were less responsive to LPS thanmacrophages were. Our observations contribute to the understanding of Chagas diseasepathogenesis, as based on the high susceptibility of autonomic glial cells toT. cruzi infection with subsequent NO production. Moreover, our findingswill facilitate future research into the immune responses and activation mechanismsof peripheral glial cells, which are important for understanding the paradoxicalresponses of this cell type in neuronal lesions and neuroprotection.     

Cultivable fungi present in deep-sea sediments of Antarctica: taxonomy,diversity, and bioprospecting of bioactive compounds

Extremophiles - We accessed the culturable mycobiota present in marine sediments at different depths in Antarctica Ocean. Acremonium fusidioides, Penicillium allii-sativi, Penicillium chrysogenum,...     

Patterns and drivers of Araucaria araucana forest growth along a biophysical gradient in the northern Patagonian Andes: Linking tree rings with satellite observations of soil moisture

Araucaria araucana (Araucaria) is a long‐lived conifer growing along a sharp west–east biophysical gradient in the Patagonian Andes. The patterns and climate drivers of Araucaria growth have typically been documented on the driest part of the gradient relying on correlations with meteorological records, but the lack of in situ soil moisture observations has precluded an assessment of the growth responses to soil moisture variability. Here, we use a network of 21 tree‐ring width chronologies to investigate the spatiotemporal patterns of tree growth through the entire gradient and evaluate their linkages with regional climate and satellite‐observed surface soil moisture variability. We found that temporal variations in tree growth are remarkably similar throughout the gradient and largely driven by soil moisture variability. The regional spatiotemporal pattern of tree growth was positively correlated with precipitation (r = 0.35 for January 1920–1974; P < 0.01) and predominantly negatively correlated with temperature (r = ?0.38 for January–March 1920–1974; P < 0.01) during the previous growing season. These correlations suggest a temporally lagged growth response to summer moisture that could be associated with known physiological carry‐over processes in conifers and to a response to moisture variability at deeper layers of the rooting zone. Notably, satellite observations revealed a previously unobserved response of Araucaria growth to summer surface soil moisture during the current rather than the previous growing season (r = 0.65 for 1979–2000; P < 0.05). This new response has a large spatial footprint across the mid‐latitudes of the South American continent (35°–45°S) and highlights the potential of Araucaria tree rings for palaeoclimatic applications. The strong moisture constraint on tree growth revealed by satellite observations suggests that projected summer drying during the coming decades may result in regional growth declines in Araucaria forests and other water‐limited ecosystems in the Patagonian Andes.     

The isolation and characteristics of plasmids derived from the insertion of MupAp1 into pML2: their behavior during transposition

Three independent insertions of the phage Mu variant MupAp1 into the ColE1 derivative pML2 have been isolated. From one of these hybrid plasmids (pSU1), two mini-Mu plasmids have been generated. These have lost internal regions of the Mu genome but retain the ends of the prophage. In pSU17 all but one kilobase pair of the early region and most of the late region have been deleted whereas in pSU123 most of the early region is still present but the deletion covers nearly all the late region. Mu immunity, host killing, and transposition functions are located in the DNA present in pSU123 but absent from pSU17. Transposition of Mu and the mini-Mu from the hybrid plasmids to the sex factor R388 is usually associated with the formation of cointegrates between the two parental plasmids.     

Recent decrease in chinstrap penguin (<Emphasis Type="Italic">Pygoscelis antarctica</Emphasis>) populations at two of Admiralty Bay’s islets on King George Island,South Shetland Islands,Antarctica

We examined the breeding populations of chinstrap penguins (Pygoscelis antarctica) on Chabrier Rock and Shag Island within Admiralty Bay, King George Island, South Shetland Islands, Antarctica from 2002 to 2004. When comparing our results to historic data from 1979, we found an overall decline of 57% in the last 25 years, mirroring the population trend of this species in other regions of the Antarctic Peninsula. Our results are discussed in relation to factors hypothesized to be driving the declines found at other sites, as well as the importance of consistent annual censuses to accurately determine population trends.     

Co-infection with the friend retrovirus and mouse scrapie does not alter prion disease pathogenesis in susceptible mice

Prion diseases are fatal, transmissible neurodegenerative diseases of the central nervous system. An abnormally protease-resistant and insoluble form (PrP(Sc)) of the normally soluble protease-sensitive host prion protein (PrP(C)) is the major component of the infectious prion. During the course of prion disease, PrP(Sc) accumulates primarily in the lymphoreticular and central nervous systems. Recent studies have shown that co-infection of prion-infected fibroblast cells with the Moloney murine leukemia virus (Mo-MuLV) strongly enhanced the release and spread of scrapie infectivity in cell culture, suggesting that retroviral coinfection might significantly influence prion spread and disease incubation times in vivo. We now show that another retrovirus, the murine leukemia virus Friend (F-MuLV), also enhanced the release and spread of scrapie infectivity in cell culture. However, peripheral co-infection of mice with both Friend virus and the mouse scrapie strain 22L did not alter scrapie disease incubation times, the levels of PrP(Sc) in the brain or spleen, or the distribution of pathological lesions in the brain. Thus, retroviral co-infection does not necessarily alter prion disease pathogenesis in vivo, most likely because of different cell-specific sites of replication for scrapie and F-MuLV.     

Interaction of Photoprotective and Acclimation Mechanisms in Ulva rigida (Chlorophyta) in Response to Diurnal Changes in Solar Radiation in Southern Chile

Species of the genus Ulva (Chlorophyta) are regarded as opportunistic organisms, which efficiently adjust their metabolism to the prevailing environmental conditions. In this study, changes in chlorophyll‐a fluorescence‐based photoinhibition of photosynthesis, electron transport rates, photosynthetic pigments, lipid peroxidation, total phenolic compounds, and antioxidant metabolism were investigated during a diurnal cycle of natural solar radiation in summer (for 12 h) under two treatments: photosynthetically active radiation (PAR: 400–700 nm) and PAR+ ultraviolet (UV) radiation (280–700 nm). In the presence of PAR alone, Ulva rigida showed dynamic photoinhibition, and photosynthetic parameters and pigment concentrations decreased with the intensification of the radiation. On the other hand, under PAR+UV conditions a substantial decline up to 43% was detected and an incomplete fluorescence recovery, also, P‐I curve values remained low in relation to the initial condition. The phenolic compounds increased their concentration only in UV radiation treatments without showing a correlation with the antioxidant activity. The enzimatic activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) increased over 2‐fold respect at initial values during the onset of light intensity. In contrast, catalase (CAT) increased its activity rapidly in response to the radiation stress to reach maxima at 10 a.m. and decreasing during solar. The present study suggests that U. rigida is capable of acclimating to natural radiation stress relies on a concerted action of various physiological mechanisms that act at different times of the day and under different levels of environmental stress.