The neonicotinoid insecticide imidacloprid (IMI) affects the insect central nervous system and is successfully applied to control pests for a variety of agricultural crops. In the current study, ...acute toxicity and genotoxicity of the IMI-containing commercial formulation insecticide Glacoxan Imida (35 percent IMI) was evaluated on Hypsiboas pulchellus (Anura: Hylidae) tadpoles exposed under laboratory conditions. A lethal effect was evaluated as the end point for lethality, whereas micronucleus (MN) frequency and DNA single-strand breaks evaluated by the single cell gel electrophoresis (SCGE) assay were employed as end points for genotoxicity. Sublethal end points were assayed within the 12.5–37.5mg/L IMI concentration range. Experiments were performed on tadpoles at stage 36 (range, 35–37) according to the classification proposed by Gosner. Lethality studies revealed an LC50 96h value of 52.622mg/L IMI. Increased frequency of MNs was only observed when 25.0mg/L was assayed for 96h, whereas no other nuclear abnormalities were induced. Increase of the genetic damage index was observed at 48h of treatment within the 12.5–37.5mg/L concentration range, whereas an increased frequency of DNA damage was observed only in tadpoles treated with 37.5mg/L IMI for 96h. This study represents the first evidence of the acute lethal and genotoxic effects exerted by IMI on tadpoles of an amphibian species native to Argentina under laboratory conditions.
•IMI lethal and genotoxic properties were evaluated on Hypsiboas pulchellus.•Determination of LC50 96h was employed as lethal end point.•IMI induced micronuclei and DNA single-strand breaks in circulating blood cells.•First evidence of genotoxicity exerted by IMI on an Argentinean amphibian species.
In this study we determined the causes of mortality and disease in a total of 325 lagomorphs (rabbits and hares) in northern Spain between 2000 and 2018. Risk factors such as the species, age, sex, ...time of year and origin were also considered. Clinical signs, gross and histopathological findings and ancillary test results were the basis for the final diagnoses that were reviewed to classify and identify the different disorders. A total of 26 different conditions were identified. A single cause of death or illness was detected in 267 animals. They were grouped into parasitic conditions (
= 65; 24.34%) represented by encephalitozoonosis, hepatic coccidiosis, hepatoperitoneal cysticercosis, intestinal coccidiosis, parasitic gastritis and cutaneous ectoparasitosis; bacterial diseases (
= 56; 20.97%) including pseudotuberculosis, blue breast, skin abscesses, tularemia, pneumonic pasteurellosis and staphylococcal infections; nutritional and metabolic diseases (
= 48; 17.97%) with epizootic rabbit enteropathy, hepatic steatosis and pregnancy toxemia as prominent diseases; viral infections (
= 31; 11.61%) comprising rabbit hemorrhagic disease and myxomatosis and miscellaneous causes (
= 31; 11.61%) where rabbit enteritis complex, renal conditions (nephrosis), heat stroke, and arterial bone metaplasia were included; neoplasms (
= 12; 4.49%) represented by uterine adenocarcinoma, mammary adenocarcinoma, cutaneous fibroma, intestinal lymphoma and hepatic cholangiocarcinoma; toxicoses (
= 11; 4.11%); trauma-related injuries (
= 9; 3.37%) and finally congenital diseases (
= 4; 1.49%). In 58 animals of the study, some of these conditions were presented jointly. We discuss the detection frequency, possible causes or associated factors of the different pathologies as well as the importance of the different variables considered.
Isothiocyanates (ITCs) have gained increasing attention since they have been attributed the merits for the potential beneficial effects of cruciferous vegetable dietary consumption on cancer. The aim ...of the present study was to determine the cytotoxic effects of 3-butenyl ITC (3-BI) on prostate cancer (PC) cells under in vitro conditions. Two androgen-insensitive human PC cell lines, PC-3 and DU145, were assayed. Cells were cultured in the presence of increasing concentrations of 3-BI (5, 10, 30 and 50 µM) in the absence or presence of the chemotherapeutic drug docetaxel (DOCE) (1 and 2 nM). The cytotoxic effects of these compounds were analyzed using the trypan blue exclusion assay at 24, 48 and 72 h. Apoptosis and migration assays were also performed. The results showed that 3-BI induced a dose-dependent cytotoxic effect on PC-3 cells at 24, 48 and 72 h. These effects were significantly higher than those found with DOCE at 72 h of culture. Moreover, 3-BI also potentiated the effects of DOCE in a dose-dependent manner. Additionally, 3-BI showed inhibition of the migration of PC-3 cells. Nevertheless, 3-BI was not effective in the DU145 PC cell line. These results show a promising role for the 3-BI compound as a co-adjuvant agent in DOCE-based therapy in certain types of PC.
Genotoxic, biochemical, and individual organizational effects on
Leptodactylus latinasus
tadpoles were evaluated after exposure to an imazethapyr (IMZT)-based commercial herbicide formulation, Pivot® ...H (10.59% IMZT). A determination of the value of the lethal concentration (LC50) was determined as a toxicological endpoint. Alterations in animal behavior and morphological abnormalities as well as cholinesterase (ChE), catalase (CAT), and glutathione
S
-transferase (GST) activities were employed as individual sublethal endpoints. Micronuclei frequencies (MNs), binucleated cells (BNs), blebbed nuclei (BLs), lobed nuclei (LBs), notched nuclei (NTs), erythroplastids (EPs), and evaluation of DNA strand breaks were employed as genotoxic endpoints. All biomarkers were evaluated after 48 and 96 h of exposure to concentrations of IMZT within 0.07–4.89 mg/L. LC50
96h
values of 1.01 and 0.29 mg/L IMZT were obtained for Gosner stages 25 and 36, respectively. Irregular swimming, diamond body shape, and decreased frequency of keratodonts were detected at both sampling times. Results showed that IMZT increased GST activity and MN frequency at 48 and 96 h of exposure. Other nuclear abnormalities were also observed in the circulating erythrocytes of tadpoles, i.e., NT and BL values after 48 h, and LN, BL, and EP values after 96 h. Finally, results showed that IMZT within 0.07–0.22 mg/L increased the genetic damage index in tadpoles exposed for both exposure times (48 and 96 h). This study is the first to report the sublethal biochemical effects of IMZT in anurans and is also the first report using
L. latinasus
tadpoles as a bioindicator for ecotoxicological studies.
AIM:To assess the fecal immunochemical test(FIT)accuracy for colorectal cancer(CRC)and advanced neoplasia(AN)detection in CRC screening.METHODS:We performed a multicentric,prospective,double blind ...study of diagnostic tests on asymptomatic average-risk individuals submitted to screening colonoscopy.Two stool samples were collected and the fecal hemoglobin concentration was determined in the first sample(FIT1)and the highest level of both samples(FITmax)using the OC-sensor.Areas under the curve(AUC)for CRC and AN were calculated.The best FIT1and FITmax cut-off values for CRC were determined.At this threshold,number needed to scope(NNS)to detect a CRC and an AN and the cost per lesion detected were calculated.RESULTS:About 779 individuals were included.An AN was found in 97(12.5%)individuals:a CRC in 5(0.6%)and an advanced adenoma(≥10 mm,villous histology or high grade dysplasia)in 92(11.9%)subjects.For CRC diagnosis,FIT1 AUC was 0.96(95%CI:0.95-0.98)and FITmax AUC was 0.95(95%CI:0.93-0.97).For AN,FIT1 and FITmax AUC were similar(0.72,95%CI:0.66-0.78 vs 0.73,95%CI:0.68-0.79,respectively,P=0.34).Depending on the number of determinations and the positivity threshold cut-off used sensitivity for AN detection ranged between 28%and 42%and specificity between 91%and 97%.At the best cut-off point for CRC detection(115 ng/mL),the NNS to detect a CRC were 10.2 and 15.8;and the cost per CRC was 1814and 2985on FIT1 and FITmax strategies respectively.At this threshold the sensitivity,NNS and cost per AN detected were 30%,1.76,and 306,in FIT1 strategy,and 36%,2.26and 426,in FITmax strategy,respectively.CONCLUSION:Performing two tests does not improve diagnostic accuracy,but increases cost and NNS to detect a lesion.
The result of the multidisciplinary collaboration of researchers from different areas of knowledge to validate a solar radiation model is presented. The MAPsol is a 3D local-scale adaptive solar ...radiation model that allows us to estimate direct, diffuse, and reflected irradiance for clear sky conditions. The model includes the adaptation of the mesh to complex orography and albedo, and considers the shadows cast by the terrain and buildings. The surface mesh generation is based on surface refinement, smoothing and parameterization techniques and allows the generation of high-quality adapted meshes with a reasonable number of elements. Another key aspect of the paper is the generation of a high-resolution digital elevation model (DEM). This high-resolution DEM is constructed from LiDAR data, and its resolution is two times more accurate than the publicly available DEMs. The validation process uses direct and global solar irradiance data obtained from pyranometers at the University of Salamanca located in an urban area affected by systematic shading from nearby buildings. This work provides an efficient protocol for studying solar resources, with particular emphasis on areas of complex orography and dense buildings where shadows can potentially make solar energy production facilities less efficient.
Biomolecular condensates have emerged as important structures in cellular function and disease, and are thought to form through liquid‐liquid phase separation (LLPS). Thorough and efficient in vitro ...experiments are therefore needed to elucidate the driving forces of protein LLPS and the possibility to modulate it with drugs. Here we present Taylor dispersion‐induced phase separation (TDIPS), a method to robustly measure condensation phenomena using a commercially available microfluidic platform. It uses only nanoliters of sample, does not require extrinsic fluorescent labels, and is straightforward to implement. We demonstrate TDIPS by screening the phase behaviour of two proteins that form biomolecular condensates in vivo, PGL‐3 and Ddx4. Uniquely accessible to this method, we find an unexpected re‐entrant behaviour at very low ionic strength, where LLPS is inhibited for both proteins. TDIPS can also probe the reversibility of assemblies, which was shown for both α‐synuclein and for lysozyme, relevant for health and biotechnology, respectively. Finally, we highlight how effective inhibition concentrations and partitioning of LLPS‐modifying compounds can be screened highly efficiently.
Protein phase separation (PPS) is important in functional and disease biology but is challenging to study. We present Taylor dispersion induced phase separation (TDIPS) to study PPS in a reaction‐diffusion system inside a microfluidic capillary. The resulting data is highly information‐rich and allows for thermodynamic analysis but also efficient screening campaigns of phase separation‐modulating compounds using only nanoliters of sample per data point.
Abstract
We investigate the magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process through the calorimetric method. Specifically, we propose a theoretical approach to magnetic ...hyperthermia from a thermodynamic point of view. To test the robustness of the approach, we perform hyperthermia experiments and analyse the thermal behavior of magnetite and magnesium ferrite magnetic nanoparticles dispersed in water submitted to an alternating magnetic field. From our findings, besides estimating the specific loss power value from a non-adiabatic and radiating process, thus enhancing the accuracy in the determination of this quantity, we provide physical meaning to a parameter found in literature that still remained not fully understood, the effective thermal conductance, and bring to light how it can be obtained from experiment. In addition, we show our approach brings a correction to the estimated experimental results for specific loss power and effective thermal conductance, thus demonstrating the importance of the heat loss rate due to the thermal radiation in magnetic hyperthermia.
It has long been proposed that phase-separated compartments can provide a basis for the formation of cellular precursors in prebiotic environments. However, we know very little about the properties ...of coacervates formed from simple peptides, their compatibility with ribozymes or their functional significance. Here we assess the conditions under which functional ribozymes form coacervates with simple peptides. We find coacervation to be most robust when transitioning from long homopeptides to shorter, more pre-biologically plausible heteropeptides. We mechanistically show that these RNA-peptide coacervates display peptide-dependent material properties and cofactor concentrations. We find that the interspacing of cationic and neutral amino acids increases RNA mobility, and we use isothermal calorimetry to reveal sequence-dependent Mg
partitioning, two critical factors that together enable ribozyme activity. Our results establish how peptides of limited length, homogeneity and charge density facilitate the compartmentalization of active ribozymes into non-gelating, magnesium-rich coacervates, a scenario that could be applicable to cellular precursors with peptide-dependent functional phenotypes.
Phytoplankton Calcification in a High-CO₂ World Iglesias-Rodriguez, M. Debora; Halloran, Paul R; Rickaby, Rosalind E.M ...
Science (American Association for the Advancement of Science),
04/2008, Letnik:
320, Številka:
5874
Journal Article
Recenzirano
Ocean acidification in response to rising atmospheric CO₂ partial pressures is widely expected to reduce calcification by marine organisms. From the mid-Mesozoic, coccolithophores have been major ...calcium carbonate producers in the world's oceans, today accounting for about a third of the total marine CaCO₃ production. Here, we present laboratory evidence that calcification and net primary production in the coccolithophore species Emiliania huxleyi are significantly increased by high CO₂ partial pressures. Field evidence from the deep ocean is consistent with these laboratory conclusions, indicating that over the past 220 years there has been a 40% increase in average coccolith mass. Our findings show that coccolithophores are already responding and will probably continue to respond to rising atmospheric CO₂ partial pressures, which has important implications for biogeochemical modeling of future oceans and climate.
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