Extra domain B of fibronectin (FN-EDB) is upregulated in the extracellular matrix during tissue remodeling and has been postulated as a potential biomarker for atherosclerosis, yet no systematic test ...for FN-EDB in plaques has been reported. We hypothesized that FN-EDB expression would intensify in advanced plaques. Furthermore, engineering of FN-EDB-targeted nanoparticles (NPs) could enable imaging/diagnosis and local delivery of payloads to plaques.
The amount of FN-EDB in human atherosclerotic and normal arteries (ages: 40 to 85 years) was assessed by histological staining and quantification using an FN-EDB-specific aptide (APT
). FN-EDB-specific NPs that could serve as MRI beacons were constructed by immobilizing APT
on the NP surface containing DTPAGd. MRI visualized APT
-GdNPs administered to atherosclerotic apolipoprotein E-deficient mice in the brachiocephalic arteries. Analysis of the ascending-to-descending thoracic aortas and the aortic roots of the mice permitted quantitation of Gd, FN-EDB, and APT
-GdNPs. Cyanine, a model small molecule drug, was used to study the biodistribution and pharmacokinetics of APT
-NPs to evaluate their utility for drug delivery.
Atherosclerotic tissues had significantly greater FN-EDB-positive areas than normal arteries (
< 0.001). This signal pertained particularly to Type III (
< 0.01), IV (
< 0.01), and V lesions (
< 0.001) rather than Type I and II lesions (AHA classification). FN-EDB expression was positively correlated with macrophage accumulation and neoangiogenesis. Quantitative analysis of T1-weighted images of atherosclerotic mice revealed substantial APT
-GdNPs accumulation in plaques compared to control NPs, conventional MRI contrast agent (Gd-DTPA) or accumulation in wild-type C57BL/6J mice. Additionally, the APT
-NPs significantly prolonged the blood-circulation time (t
: ~ 6 h) of a model drug and increased its accumulation in plaques (6.9-fold higher accumulation vs. free drug).
Our findings demonstrate augmented FN-EDB expression in Type III, IV, and V atheromata and that APT
-NPs could serve as a platform for identifying and/or delivering agents locally to a subset of atherosclerotic plaques.
Ablation of Au and Ag targets in water by a Cu vapor laser generates Au and Ag sols. The metal nanoparticles obtained after evaporation are disk-shaped (diameter in the 20–60 nm range, thickness of ...few nanometers). Their formation is observed at laser fluence between 10 and
20
J/
cm
2
. Both aqueous sols are characterized by well-resolved plasmon bands around 400 nm (Ag) and 520 nm (Au).
Despite the efficiency of transgenic plants expressing Bacillus thuringiensis (Bt) toxins as insecticides against several lepidopterans, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is ...one species that presents low susceptibility to most Bt crops. This study investigated the effects of the Cry 1 Ac toxin expressed by Bt cotton in the midgut of S. frugiperda and its effects on the humoral and cellular immune responses. Three hypotheses were proposed and tested with contributing factors for the natural tolerance of S. frugiperda: (i) midgut regenerative cells are activated by the Cry 1 Ac toxin, and thus renew the epithelial cells damaged by the protein, (ii) Cry 1 Ac increased production of nitric oxide or phenoloxidase in the hemolymph, and (iii) there are qualitative and quantitative variations in the hemocyte levels of S. frugiperda. Caterpillars were reared using Bt cotton (Acala 90B) and non-Bt isolines (Acala 90), from the first to the fourth instar. The Bt cotton promoted elongation of the epithelial cells in the midgut of S. frugiperda caterpillars. Hence, evidence only supported the hypothesised increase of phenoloxidase (ii) and qualitative and quantitative differences in hemocyte levels (iii) in insects that were fed with Bt and non-Bt cotton. These parameters seem to explain the low susceptibility of S. frugiperda to Cry 1 Ac toxin and they are a viable set of responses for the evaluation of other xenobiotic factors.
Although the large use of diethylcarbamazine (DEC), as the major anti-filaricide drug, its mechanism of action remains a matter of controversy. Several authors defend the hypothesis that DEC has no ...direct effect on nematodes. This study demonstrated that infective larvae (L3) of
Wuchereria bancrofti treated in vitro with DEC presented several behaviour and morphological changes.
The first alteration produced by treatment for 2 h with 3, 5, 10 μg/ml of DEC was the reduction of motility. Larvae treated with 5, 10 μg/ml DEC showed severely affected organelles, formation of several vacuoles, mainly in neurocytes and in the muscle cells, and dissolution of cytoplasm. Some larvae showed extreme cellular disorganization with abundance of large and dense mitochondria and numerous large vacuoles containing residual organelles. Lamellar bodies, probably related to an assembly of hipodermal membranes, were also observed in some damaged larvae.
Thus, undoubtedly in vitro treatment with concentrations of DEC similar to therapeutic conditions, which are 1–5 μg/ml (
Hawking, 1979), had a direct effect on infective larvae of
W. bancrofti by causing, primarily neuromuscular alterations with subsequent damage to organelles.
Ultrathin sections of microfilariae of Wuchereria bancrofti embedded in hydrophilic resin were incubated with sera from patients, using antisera from asymptomatic microfilaremic patients with ...different microfilarial densities 1-100 microfilariae (mf)/ml, 101-500 mf/ml, > 1,000 mf/ml. All groups studied showed reactivity against relevant epitopes in all tissues of microfilariae of W. bancrofti, instead of being localized in a specific nematode region, although the number of colloidal per square micron was inversely proportional to the microfilaremia. Such results confirm data obtained by other authors and indicate a possible role for the humoral response in the mechanism for the destruction of circulating microfilariae.
Abstract
Background
Repellent use during pregnancy was strongly recommended after uncovering Zika virus (ZIKV) involvement with congenital malformations. In this context, Pernambuco, Brazil played a ...key role since it was the epicentre for the main studies suggesting ZIKV teratogenicity and one of Brazil’s most affected states during the 2014–2016 epidemics. Thus we aimed to identify possible associations between social determinants of health and repellent use in pregnancy during the ZIKV outbreak in Pernambuco.
Methods
We conducted a cross-sectional study (July–December 2016) with 539 pregnant women residing in Pernambuco and estimated the associations by prevalence ratio and multivariable logistic regression.
Results
Repellents were associated with pregnant women ≥30 y; graduates, employed, health professionals, private health system users and with a monthly income per person greater than two minimum wages. Women whose domiciles favour mosquitoes (ground-floor houses, intermittent water supply from general distribution or water trucks and for ≤6 d/week, cesspools/open wastewater, indoor household water storage) were less likely to use repellents. There was no association for peridomiciles.
Conclusions
Repellents were not associated with ZIKV in most vulnerable pregnant women, despite all the general recommendations made during the Pernambuco epidemic. This study observed a demand for public policies focused on health, education and sanitation problems related to deprived social groups along with their co-responsibility rather than focusing on individual attitudes against mosquitoes.
Does the posture of a patient have an effect on the organ and tissue absorbed doses caused by x-ray examinations? This study aims to find the answer to this question, based on Monte Carlo (MC) ...simulations of commonly performed x-ray examinations using adult phantoms modelled to represent humans in standing as well as in the supine posture. The recently published FASH (female adult mesh) and MASH (male adult mesh) phantoms have the standing posture. In a first step, both phantoms were updated with respect to their anatomy: glandular tissue was separated from adipose tissue in the breasts, visceral fat was separated from subcutaneous fat, cartilage was segmented in ears, nose and around the thyroid, and the mass of the right lung is now 15% greater than the left lung. The updated versions are called FASH2_sta and MASH2_sta (sta = standing). Taking into account the gravitational effects on organ position and fat distribution, supine versions of the FASH2 and the MASH2 phantoms have been developed in this study and called FASH2_sup and MASH2_sup. MC simulations of external whole-body exposure to monoenergetic photons and partial-body exposure to x-rays have been made with the standing and supine FASH2 and MASH2 phantoms. For external whole-body exposure for AP and PA projection with photon energies above 30 keV, the effective dose did not change by more than 5% when the posture changed from standing to supine or vice versa. Apart from that, the supine posture is quite rare in occupational radiation protection from whole-body exposure. However, in the x-ray diagnosis supine posture is frequently used for patients submitted to examinations. Changes of organ absorbed doses up to 60% were found for simulations of chest and abdomen radiographs if the posture changed from standing to supine or vice versa. A further increase of differences between posture-specific organ and tissue absorbed doses with increasing whole-body mass is to be expected.
Ultrathin sections of L3 of Wuchereria bancrofti embedded in hydrophilic resin were incubated with antisera pools from individuals (1) asymptomatic microfilaremic with different microfilaria (mf) ...densities (1–100, 101–500, and >1,000 mf/ml); (2) chronic with hydrocele or lymphedema; and (3) with no evidence of microfilaremia or clinical filariasis but residing in an endemic area. The groups of microfilaremic subjects studied presented differences relative to the intensity of labeling, with the density of gold particles per square micrometer proportional to microfilaremia. Incubation of ultrathin sections of W. bancrofti L3 larvae in the presence of antisera from patients exhibiting chronic obstructive lymphatic pathology of hydrocele and from individuals with clear clinical evidence of lymphedema exhibited a strong reaction in the same tissues. Except for the endemic normal group, all groups studied showed reactivity against epitopes in all tissues of infective larvae of W. bancrofti. The cuticle presented an intense labeling, suggesting a possible target structure for immune response.
Seine river water was used as natural environmental medium to study the ecotoxicological impact of ZnO and CdS nanoparticles and Zn
and Cd
free ions using
as a biological target. It was demonstrated ...by viability tests and photosynthetic activity measurements that free Zn
(
= 2.7 × 10
M) is less toxic than free Cd
and ZnO nanoparticles (
= 1.4 × 10
M). In the case of cadmium species, free Cd
(
= 3.5 × 10
M) was similar to CdS nanoparticles (CdS-1:
= 1.9 × 10
M and CdS-2:
= 1.9 × 10
M), as follows: CdS > Cd
> ZnO > Zn
. Adenosine-5'-triphosphate (ATP) assay and superoxide dismutase (SOD) enzymatic activity confirmed these results. Transmission electron microscopy (TEM), coupled with energy-dispersive X-ray spectroscopy (EDS), confirmed the internalization of CdS-1 nanoparticles after 48 h of contact with
at 10
M. With a higher concentration of nanoparticles (10
M), ZnO and CdS-2 were also localized inside cells.
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