The main objective of this study was to perform laboratory experiments on calcium nitrate addition to sediments of a tropical eutrophic urban reservoir (Ibirité reservoir, SE Brazil) to immobilize ...the reactive soluble phosphorus (RSP) and to evaluate possible geochemical changes and toxic effects caused by this treatment. Reductions of 75 and 89% in the concentration of RSP were observed in the water column and interstitial water, respectively, after 145 days of nitrate addition. The nitrate application increased the rate of autotrophic denitrification, causing a consumption of 98% of the added nitrate and oxidation of 99% of the acid volatile sulfide. As a consequence, there were increases in the sulfate and iron (II) concentrations in the sediment interstitial water and water column, as well as changes in the copper speciation in the sediments. Toxicity tests initially indicated that the high concentrations of nitrate and nitrite in the sediment interstitial water (up to 2300 mg L−1 and 260 mg L−1, respectively) were the major cause of mortality of Ceriodaphnia silvestrii and Chironomus xanthus. However, at the end of the experiment, the sediment toxicity was completely removed and a reduction in the 48 h-EC50 of the water was also observed. Based on these results we can say that calcium nitrate treatment proved to be a valuable tool in remediation of eutrophic aquatic ecosystems leading to conditions that can support a great diversity of organisms after a restoration period.
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► Nitrate addition cause iron oxidation, which reduces the RSP flow from sediments to water column. ► AVS oxidation, alkalinity and nitrate consumption indicate autotrophic denitrification process. ► Nitrate addition as sediment restoration technology may cause toxicity to aquatic organisms.
Extracellular traps (ETs), web-like structures composed of DNA and histones, are released by innate immune cells in a wide range of organisms. ETs capture microorganisms, thereby avoiding their ...spread, and also concentrate antimicrobial molecules, which helps to kill microbes. Although vertebrate innate immune systems share homology with the insect immune system, ETosis have yet to be characterized in insects. Here, we report that the hemocytes of the hemimetabolous insect Periplaneta americana release ETs upon in vitro stimulation. We further discuss the relationship between ETs and nodulation and in controlling bacterial spread in vivo.
•Hemocytes from Periplaneta americana cast DNA extracellular traps (ETs) similarly to vertebrates and invertebrate organisms.•Roaches ETs were triggered by LPS, Gram-positive and Gram-negative bacteria.•ETs contribute to a rapid and efficient nodulation needed to block bacteria spread in the insect in vivo.
The aim of this study was to evaluate reader variability in screening mammograms according to the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) assessment and ...breast density categories.
A stratified random sample of 100 mammograms was selected from a population-based breast cancer screening programme in Barcelona, Spain: 13 histopathologically confirmed breast cancers and 51 with true-negative and 36 with false-positive results. 21 expert radiologists from radiological units of breast cancer screening programmes in Catalonia, Spain, reviewed the mammography images twice within a 6-month interval. The readers described each mammography using BI-RADS assessment and breast density categories. Inter- and intraradiologist agreement was assessed using percentage of concordance and the kappa (κ) statistic.
Fair interobserver agreement was observed for the BI-RADS assessment κ=0.37, 95% confidence interval (CI) 0.36-0.38. When the categories were collapsed in terms of whether additional evaluation was required (Categories III, 0, IV, V) or not (I and II), moderate agreement was found (κ=0.53, 95% CI 0.52-0.54). Intra-observer agreement for BI-RADS assessment was moderate using all categories (κ=0.53, 95% CI 0.50-0.55) and substantial on recall (κ=0.66, 95% CI 0.63-0.70). Regarding breast density, inter- and intraradiologist agreement was substantial (κ=0.73, 95% CI 0.72-0.74 and κ=0.69, 95% CI 0.68-0.70, respectively).
We observed a substantial intra-observer agreement in the BI-RADS assessment but only moderate interobserver agreement. Both inter- and intra-observer agreement in mammographic interpretation of breast density was substantial. Advances in knowledge Educational efforts should be made to decrease radiologists' variability in BI-RADS assessment interpretation in population-based breast screening programmes.
We performed Ecological Niche Models (ENMs) to generate climatically suitable areas for anurans in the Brazilian hotspots, the Atlantic Forest (AF), and Cerrado (CER), considering the baseline and ...future climate change scenarios, to evaluate the differences in the alpha and beta diversity metrics across time. We surveyed anuran occurrence records and generated ENMs for 350 and 155 species in the AF and CER. The final predictive maps for the baseline, 2050, and 2070 climate scenarios, based on an ensemble approach, were used to estimate the alpha (local species richness) and beta diversity metrics (local contribution to beta diversity index and its decomposition into replacement and nestedness components) in each ~50 × 50 km grid cell of the hotspots. Climate change is not expected to drastically change the distribution of the anuran richness gradients, but to negatively impact their whole extensions (i.e., cause species losses throughout the hotspots), except the northeastern CER that is expected to gain in species richness. Areas having high beta diversity are expected to decrease in northeastern CER, whereas an increase is expected in southeastern/southwestern CER under climate change. High beta diversity areas are expected to remain in the same AF locations as the prediction of the baseline climate, but the predominance of species loss under climate change is expected to increase the nestedness component in the hotspot. These results suggest that the lack of similar climatically suitable areas for most species will be the main challenge that species will face in the future. Finally, the application of the present framework to a wide range of taxa is an important step for the conservation of threatened biomes.
We performed Ecological Niche Models (ENMs) to generate anuran climatically suitable areas in the Brazilian hotspots, considering the baseline and future climate change scenarios, to evaluate the differences on the alpha and beta diversity metrics across time. Climate change is not expected to drastically change the distribution of the anuran richness gradients, but to negatively impact their whole extensions (i.e., cause species losses throughout the hotspots). The results suggest that the lack of similar climatically suitable areas for most species will be the main challenge that species will face in the future.
Abstract
Limited information is available about the effect of mid-pregnancy viral infections on the placental expression of efflux transporters and offspring behavior. We hypothesized that maternal ...exposure to polyinosinic-polycytidylic acid poly(I:C), a synthetic double-stranded RNA viral mimic, would impair placental cell turnover, the expression of selected ABC transporters and adult offspring behavior. C57BL/6 mice were administered poly(I:C) (10 mg/Kg;ip) or vehicle at gestational day (GD) 13.5 (mid-pregnancy). Dams were euthanized for blood collection 4 h after injection, fetal and placental collection at GD18.5 or allowed to deliver spontaneously at term. At GD 13.5, poly(I:C) induced an acute pro-inflammatory response characterized by an increase in maternal plasma levels of IL-6, CXCL-1 and CCL-2/MCP-1. At GD 18.5, poly(I:C) decreased cell proliferation/death in the labyrinthine and increased cell death in the junctional zones, characterizing a disruption of placental cell turnover. Abca1 and Abcg1 immunolabelling was decreased in the labyrinthine zone, whereas Abca1, Abcg1 and breast cancer resistance transporter (Bcrp) expression increased in the junctional zone. Moreover, adult offspring showed motor and cognitive impairments in the Rotarod and T-water maze tests. These results indicate that viral infection during mid-pregnancy may disrupt relevant placental efflux transporters, as well as placental cell turnover and offspring behavior in adult life.
Cyclic lipopeptides (CLPs) are non-ribosomal biosurfactants produced by
Bacillus
species that exhibit outstanding interfacial activity. The synthesis of CLPs is under genetic and environmental ...influence, and representatives from different families are generally co-produced, generating isoforms that differ in chemical structure and biological activities. This study to evaluate the effect of low and high NaCl concentrations on the composition and surface activity of CLPs produced by
Bacillus
strains TIM27, TIM49, TIM68, and ICA13 towards microbial enhanced oil recovery (MEOR). The strains were evaluated in mineral medium containing NaCl 2.7, 66, or 100 g L
−1
and growth, surface tension and emulsification activity were monitored. Based on the analysis of 16S rDNA,
gyrB
and
rpoB
sequences TIM27 and TIM49 were assigned to
Bacillus subtilis
, TIM68 to
Bacillus vallismortis
, and ICA13 to
Bacillus amyloliquefaciens
. All strains tolerated up to 100-g L
−1
NaCl, but only TIM49 and TIM68 were able to reduce surface tension at this concentration. TIM49 also showed emulsification activity at concentrations up to 66-g L
−1
NaCl. ESI-MS analysis showed that the strains produced a mixture of CLPs, which presented distinct CLP profiles at low and high NaCl concentrations. High NaCl concentration favored the synthesis of surfactins and/or fengycins that correlated with the surface activities of TIM49 and TIM68, whereas low concentration favored the synthesis of iturins. Taken together, these findings suggest that the determination of CLP signatures under the expected condition of oil reservoirs can be useful in the guidance for choosing well-suited strains to MEOR.
Dogs are the primary urban reservoir of Leishmania infantum and play a crucial role in the transmission of this parasite to man via sandflies. The spleen and liver are the main target organs of L. ...infantum infection, but few studies have evaluated the immune response to this infection in the canine liver. To identify the immunological mediators involved in resistance and/or susceptibility to canine visceral leishmaniosis (CVL), we selected 21 dogs naturally infected by L. infantum and classified as asymptomatic or symptomatic. Immunological parameters were analysed and correlations with clinical signs were determined. Symptomatic dogs showed higher numbers of parasites and less leucocyte infiltration in the liver compared with asymptomatic dogs. The progression of this disease was characterized not only by the down regulation of T helper (Th) 1-related cytokines, such as interferon (IFN)-γ and tumour necrosis factor (TNF)-α, but also by the down regulation of genes encoding interleukin (IL)-17A, inducible nitric oxide synthase (iNOS) and IL-10 in the spleen and liver in symptomatic dogs compared with asymptomatic dogs. Importantly, IL-17A gene transcription level was positively correlated with mRNA expression for iNOS and IFN-γ. Th1- and Th17-related cytokines therefore appear to play a role in restricting parasite growth via iNOS activation and decrease susceptibility of dogs to CVL.
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After being eliminated during the 1950s, dengue reemerged in Brazil in the 1980s. Since then, incidence of the disease has increased, as serotypes move within and between cities. The co-circulation ...of multiple serotypes contributes to cycles of epidemic and interepidemic years, and a seasonal pattern of transmission is observed annually. Little is known regarding possible differences in the epidemiology of dengue under epidemic and interepidemic scenarios. This study addresses this gap and aims to assess the epidemiological characteristics and determinants of epidemic and interepidemic dengue transmission, utilizing data from the 5th largest city in Brazil (Fortaleza), at fine spatial and temporal scales.
Longitudinal models of monthly rates of confirmed dengue cases were used to estimate the differential contribution of contextual factors to dengue transmission in Fortaleza between 2011 and 2015. Models were stratified by annual climatological schedules and periods of interepidemic and epidemic transmission, controlling for social, economic, structural, entomological, and environmental factors. Results revealed distinct seasonal patterns between interepidemic and epidemic years, with persistent transmission after June in interepidemic years. Dengue was strongly associated with violence across strata, and with poverty and irregular garbage collection during periods of low transmission, but not with other indicators of public service provision or structural deprivation. Scrapyards and sites associated with tire storage were linked to incidence differentially between seasons, with the strongest associations during transitional precipitation periods. Hierarchical clustering analysis suggests that the dengue burden concentrates in the southern periphery of the city, particularly during periods of minimal transmission.
Our findings have direct programmatic implications. Vector control operations must be sustained after June even in non-epidemic years. More specifically, scrapyards and sites associated with tires (strongly associated with incidence during periods of minimal transmission), require sustained entomological surveillance, particularly during interepidemic intervals and in the urban periphery. Intersectoral collaborations that address urban violence are critical for facilitating the regular activities of vector control agents.
Abstract The aim of this study was to systematically review the prognosis of autotransplanted teeth followed up for a period of 6 years or more. A literature search was conducted in five databases ...and the eligibility criteria were established. The outcomes evaluated were the survival rate, percentage of abnormal mobility, pulpal conditions, and percentage of root resorption. The searches identified 1848 articles, and after evaluation against the eligibility criteria, six were included. Data related to outcome measures were extracted from the studies and a meta-analysis was performed. Survival rates ranged from 75.3% to 91% and the meta-analysis showed an effect size of 81% ( P < 0.0001). The percentage ankylosis ranged from 4.2% to 18.2% and the effect size was 4.8% ( P < 0.0001). Root resorption percentages ranged from 3% to 10% and the effect size was equal to 4% ( P < 0.0001). It was not possible to perform a meta-analysis of data on pulpal conditions and percentage of teeth with abnormal mobility. The results of this study showed the survival rate to be excellent, considering the observation period. The rates of ankylosis and root resorption, despite their low values, influence the prognosis of transplanted teeth.
Piperine purified from
Piper nigrum pepper (A) and its synthetic analogue phenylamide (B) are toxic to
Leishmania amazonensis parasites, an agent of cutaneous and diffuse cutaneous leishmaniasis in ...the New World.
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► Piperine and its analogue phenylamide are toxic to
Leishmania amazonensis parasites. ► They cause alterations on parasite mitochondrial structure and function. ► The parasite’s cell cycle and neutral lipid composition is affected by these compounds. ► Isobologram showed a synergism between these compounds on leishmanicidal effect. ► The use of both compounds together leads to a synergism on leishmanicdal effect.
Leishmaniasis is a tropical disease caused by protozoan parasites of the genus
Leishmania which affects 12
million people worldwide. The discovery of drugs for the treatment of leishmaniasis is a pressing concern in global health programs. The aim of this study aim was to evaluate the leishmanicidal effect of piperine and its derivatives/analogues on
Leishmania amazonensis. Our results showed that piperine and phenylamide are active against promastigotes and amastigotes in infected macrophages. Both drugs induced mitochondrial swelling, loose kinetoplast DNA, and led to loss of mitochondrial membrane potential. The promastigote cell cycle was also affected with an increase in the G1 phase cells and a decrease in the S-phase cells, respectively, after piperine and phenylamide treatment. Lipid analysis of promastigotes showed that piperine reduced triglyceride, diacylglycerol, and monoacylglycerol contents, whereas phenylamide only reduced diacylglycerol levels. Both drugs were deemed non toxic to macrophages at 50
μM as assessed by XTT (sodium 2,3,-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2H-tetrazolium inner salt), Trypan blue exclusion, and phagocytosis assays, whereas low toxicity was noted at concentrations higher than 150
μM. None of the drugs induced nitric oxide (NO) production. By contrast, piperine reduced NO production in activated macrophages. The isobologram analysis showed that piperine and phenylamide acted synergistically on the parasites suggesting that they affect different target mechanisms. These results indicate that piperine and its phenylamide analogue are candidates for development of drugs for cutaneous leishmaniasis treatment.
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