Lethal and sublethal effects of insecticides on target and non-target arthropods are a concern of pest management programs. Cycloneda sanguinea, Orius insidiosus and Chauliognathus flavipes are ...important biological control agents for aphids, whitefly, lepidopterus eggs, thrips and mites. All three test species were subjected to a toxicity study using the insecticides acephate, bifenthrin, chlorantraniliprole, chlorpyrifos, deltamethrin, imidacloprid, and thiamethoxam. Experiments were done in the lab and field. In the laboratory we evaluated the mortality and sublethal effects of the concentration that killed 20% of the population (LC20) on feeding, repellence and reproduction of the species tested. The lethal effects of these insecticides at the recommended doses was evaluated in the field. Concentration-response bioassays indicated chlorantraniliprole had the lowest toxicity, while chlorpyrifos and acephate were the most toxic. Test species exposed to filter paper surfaces treated with pyrethroids, neonicotinoids and organophosphates were repelled. On the other hand, test species were not repelled from surfaces treated with chlorantraniliprole. Chlorantraniliprole therefore seemed to be the least dangerous insecticide for these three beneficial arthropod test species.
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•Safety of seven pesticides to the three beneficial insects was evaluated.•The chlorantraniliprole showed low lethal and sublethal effects to test-species.•Deltamethrin induced hormesis in Cycloneda sanguinea and Orius insidiosus.•The organophosphates and pyrethroids on predators IPM be evaluated with caution.
Chagas Disease (CD) is one of the leading causes of heart failure and sudden death in Latin America. Treatments with antioxidants have provided promising alternatives to ameliorate CD. However, the ...specific roles of major reactive oxygen species (ROS) sources, including NADPH-oxidase 2 (NOX2), mitochondrial-derived ROS and nitric oxide (NO) in the progression or resolution of CD are yet to be elucidated. We used C57BL/6 (WT) and a gp91PHOX knockout mice (PHOX-/-), lacking functional NOX2, to investigate the effects of ablation of NOX2-derived ROS production on the outcome of acute chagasic cardiomyopathy. Infected PHOX-/- cardiomyocytes displayed an overall pro-arrhythmic phenotype, notably with higher arrhythmia incidence on ECG that was followed by higher number of early afterdepolarizations (EAD) and 2.5-fold increase in action potential (AP) duration alternans, compared to AP from infected WT mice. Furthermore, infected PHOX-/- cardiomyocytes display increased diastolic Ca2+, aberrant Ca2+ transient and reduced Ca2+ transient amplitude. Cardiomyocyte contraction is reduced in infected WT and PHOX-/- mice, to a similar extent. Nevertheless, only infected PHOX-/- isolated cardiomyocytes displayed significant increase in non-triggered extra contractions (appearing in ~75% of cells). Electro-mechanical remodeling of infected PHOX-/-cardiomyocytes is associated with increase in NO and mitochondria-derived ROS production. Notably, EADs, AP duration alternans and in vivo arrhythmias were reverted by pre-incubation with nitric oxide synthase inhibitor L-NAME. Overall our data show for the first time that lack of NOX2-derived ROS promoted a pro-arrhythmic phenotype in the heart, in which the crosstalk between ROS and NO could play an important role in regulating cardiomyocyte electro-mechanical function during acute CD. Future studies designed to evaluate the potential role of NOX2-derived ROS in the chronic phase of CD could open new and more specific therapeutic strategies to treat CD and prevent deaths due to heart complications.
Trypanosomatids of the genera Angomonas and Strigomonas (subfamily Strigomonadinae) have long been known to contain intracellular beta-proteobacteria, which provide them with many important nutrients ...such as haem, essential amino acids and vitamins. Recently, Kentomonas sorsogonicus, a divergent member of Strigomonadinae, has been described. Herein, we characterize the genome of its endosymbiont, Candidatus Kinetoplastibacterium sorsogonicusi. This genome is completely syntenic with those of other known Ca. Kinetoplastibacterium spp., but more reduced in size (~742 kb, compared with 810-833 kb, respectively). Gene losses are not concentrated in any hot-spots but are instead distributed throughout the genome. The most conspicuous loss is that of the haem-synthesis pathway. For long, removing haemin from the culture medium has been a standard procedure in cultivating trypanosomatids isolated from insects; continued growth was considered as an evidence of endosymbiont presence. However, we demonstrate that, despite bearing the endosymbiont, K. sorsogonicus cannot grow in culture without haem. Thus, the traditional test cannot be taken as a reliable criterion for the absence or presence of endosymbionts in trypanosomatid flagellates. It remains unclear why the ability to synthesize such an essential compound was lost in Ca. K. sorsogonicusi, whereas all other known bacterial endosymbionts of trypanosomatids retain them.
Siloxanes are semi-volatile silicon compounds with properties that make them possible to use in industrial products of daily use. Due to this, the siloxanes contained in shampoos and conditioners, ...for example, are transported through the sewage and tailings for wastewater, soils, and landfills. Consequently, the biogas from sources contaminated will have a high concentration of siloxanes. In the process of combustion of gas containing these compounds, other compounds are formed as SiO and SiO
2
, and when they are in the condensed form inside the chambers, they have properties similar to those of ordinary glass. This process may cause incrustations in the engine components and the other system units, increasing the wear of the parts and the stops for maintenance, decreasing the thermal and electrical conductivity of the biogas. Searching methods for removing siloxanes from biogas in the literature, several methods were proposed, such as adsorption, absorption, gas cooling, biological removal, membranes, and others. Thus, this work aims to present the primary methods for removing several siloxane compounds from biogas from landfills and sewage and compare the removal efficiency. In general, activated carbon is the most consolidated in the literature and can vary from 13.3 to 100% in the removal efficiency of several siloxane compounds, depending on the removal process. However, industries have observed some limitations in the real process use of this material for siloxane removal into biogas.
The potato tuber moth,
Phthorimaea operculella
Zeller (Lepidoptera: Gelechiidae) is a major potato pest in the tropics and subtropics where it causes economic losses both in the field and in storage. ...The objective of this study was to determine a sampling plan that included a sampling unit and number of samples necessary for monitoring
P. operculella
infestations in potato fields. Eight commercial potato fields were monitored totaling 23 ha. All leaves from 670 plants were sampled and numbered from plant apex down. Frequency analysis was performed to select the most frequent leaves that would compose the sample unit. Next, a frequency distribution model was calculated, and the ideal number of samples needed to monitor
P. operculella
mines was obtained for the sampling plan. The most representative (highest Pearson correlation (
r
= 0.74) and determination (
R
2
= 0.55) coefficients) and precise (smallest relative variances; RV= 8.26%) sampling unit for monitoring
P. operculella
mines in potato fields was leaf 8. The frequency distribution model selected was a negative binomial and the
K
common
value was 0.8803. The ideal number of samples, based on the allowable precision error, was 23 leaves per 10 ha plot.
This work aimed to study the inheritance of resistance to Phytophthora infestans in tomato plants, using the maximum likelihood estimation function. The susceptible cultivar Santa Clara (Solanum ...lycopersicum) was used as the female genitor and the P. infestans resistant S. habrochaites f. glabratum accession (BGH 6902) as the male genitor. F1 plants from the crossing were self-pollinated to produce F2 progenies, and also backcrossed with PR and PS to produce BC1:R and BC1:S generations, respectively. The tomato plants were inoculated 50 days after transplanting. Disease severity was evaluated via a diagrammatic scale. Comparison of the genetic models created using the maximum likelihood function revealed that the inheritance of resistance to P. infestans in S. habrochaites is conferred by a major gene with additive and dominance effects, polygenes with additive effects, plus the environmental effect. Vertical resistance can be explored using genes with major effects. Programs of recurrent and maker-assisted selection are considered efficient strategies with which to select genotypes that hold P. infestans resistance conferred by polygenes.
About 270 yeast isolates were screened for xylitol production using xylose as the sole carbon source. The best isolate,
Debaryomyces hansenii UFV-170, released 5.84
g
L
−1 xylitol from 10
g
L
−1 ...xylose after 24
h, corresponding to a yield of xylitol on consumed substrate (
Y
P/S) of 0.54
g
g
−1. This strain was cultivated batch-wise at variable starting concentrations of xylose (
S
o) and biomass (
X
o) and agitation intensity, in order to improve xylitol production and to evaluate, through simple carbon balances, the influence of these conditions on xylose metabolism. Under the best microaerobic conditions (
S
o
=
53
g
L
−1,
X
o
=
1.4
g
L
−1, 200
rpm), xylitol production reached 37.0
g
L
−1, corresponding to xylitol volumetric productivity of 1.0
g
L
−1
h
−1, specific productivity of 0.22
g
g
−1
h
−1 and
Y
P/S
=
0.76
g
g
−1. Almost 83% of xylose was consumed for xylitol production, the rest being consumed for growth, while respiration was negligible. The new isolate appeared to be a promising alternative for industrial xylitol bioproduction.
Background
Cachexia is a multifactorial and multiorgan syndrome associated with cancer and other chronic diseases and characterized by severe involuntary body weight loss, disrupted metabolism, ...inflammation, anorexia, fatigue, and diminished quality of life. This syndrome affects around 50% of patients with colon cancer and is directly responsible for the death of at least 20% of all cancer patients. Systemic inflammation has been recently proposed to underline most of cachexia‐related symptoms. Nevertheless, the exact mechanisms leading to the initiation of systemic inflammation have not yet been unveiled, as patients bearing the same tumour and disease stage may or may not present cachexia. We hypothesize a role for gut barrier disruption, which may elicit persistent immune activation in the host. To address this hypothesis, we analysed the healthy colon tissue, adjacent to the tumour.
Methods
Blood and rectosigmoid colon samples (20 cm distal to tumour margin) obtained during surgery, from cachectic (CC = 25) or weight stable (WSC = 20) colon cancer patients, who signed the informed consent form, were submitted to morphological (light microscopy), immunological (immunohistochemistry and flow cytometry), and molecular (quantification of inflammatory factors by Luminex® xMAP) analyses.
Results
There was no statistical difference in gender and age between groups. The content of plasma interleukin 6 (IL‐6) and IL‐8 was augmented in cachectic patients relative to those with stable weight (P = 0.047 and P = 0.009, respectively). The number of lymphocytic aggregates/field in the gut mucosa was higher in CC than in WSC (P = 0.019), in addition to those of the lamina propria (LP) eosinophils (P < 0.001) and fibroblasts (P < 0.001). The area occupied by goblet cells in the colon mucosa was decreased in CC (P = 0.016). The M1M2 macrophages percentage was increased in the colon of CC, in relation to WSC (P = 0.042). Protein expression of IL‐7, IL‐13, and transforming growth factor beta 3 in the colon was significantly increased in CC, compared with WSC (P = 0.02, P = 0.048, and P = 0.048, respectively), and a trend towards a higher content of granulocyte‐colony stimulating factor in CC was also observed (P = 0.061). The results suggest an increased recruitment of immune cells to the colonic mucosa in CC, as compared with WSC, in a fashion that resembles repair response following injury, with higher tissue content of IL‐13 and transforming growth factor beta 3.
Conclusions
The changes in the intestinal mucosa cellularity, along with modified cytokine expression in cachexia, indicate that gut barrier alterations are associated with the syndrome.
To evaluate the association between fear of falling (FoF) and spatial and temporal parameters of gait in older adults.
This cross-sectional study evaluated 291 clients of a private health care ...insurance who were over 65 years of age and living in the North Zone of Rio de Janeiro City in 2013. FoF was assessed by the Falls Efficacy Scale-International (FES-I-BR), and gait parameters, such as gait speed, cadence, step time, step length, stride length, and variability (standard deviation of stride length), were assessed using GAITRite®. The covariates were age, sex, history of falls, number of medications, cognitive decline, body mass index, and sight impairment. The association between FoF and gait parameters was assessed by linear regression, and the respective 95% confidence intervals (95% CIs) were calculated.
The prevalence of FoF was 51.9%. The adjusted analyses showed an association between FoF and the following gait parameters: decreased gait speed, decreased cadence, increased step time, and decreased step and stride length. No association was found between FoF and stride lenght variability.
This study suggests that FoF is associated with changes in gait parameters, with the exception of stride length variability. These findings show a need for interventions to reduce FoF in older adults, which is a modifiable factor that is related to gait changes. More studies are needed to elucidate the relationship between FoF and motor control of gait in older adults.
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