Background and Aims Breast cancer is the most common cancer and the main cause of cancer deaths in women worldwide. Microvesicles (MVs) are fragments of the plasma membrane secreted from cytoplasmic ...membrane compartments by normal and malignant cells. An increase in MV number has been found in peripheral blood of patients with several diseases including cancer. We hypothesized that MV number and the relative amount of focal adhesion kinase (FAK) and epidermal growth factor receptor (EGFR) proteins in plasma fractions enriched in MVs and deprived of platelet-derived MVs are related to the presence of breast cancer. Methods Plasma fractions enriched in MVs and deprived of platelet-derived MVs were obtained by differential centrifugation of blood samples. MV number was evaluated by BD TruCOUNT Tubes (BD Biosciences). FAK and EGFR proteins were analyzed by Western blot. Results MV number in plasma fractions enriched with MVs and deprived of platelet-derived MVs is higher in breast cancer patients with stages I–IV as well as with T2–T4 tumors, in comparison to control group. In addition, plasma fractions enriched in MVs present FAK and EGFR proteins and their amount is increased in some stages of breast cancer in comparison to control group. Conclusions Our findings strongly suggest that MV number and the amount of FAK and EGFR in plasma fractions enriched in MVs are associated with some stages of breast cancer.
Studies on the feeding behavior of hematophagous insects, particularly those of medical importance, are relevant for tracking possible pathogen transmission routes and identifying biases in the ...choice of vertebrates. We evaluated host selection of blood-feeding mosquitoes in a disturbed forest in the Magdalena Medio valley in Colombia from March 2017 to April 2018, after the introduction of Zika virus to the Americas from the 2015-2016 outbreak. We estimated vertebrate diversity and collected blood-engorged female mosquitoes. Genomic DNA/RNA was extracted from the mosquito's abdomen for vertebrate host identification and pathogen detection. We performed conventional PCR and sequencing, using universal primers targeting vertebrate regions of the eukaryotic mitochondrial genome to determine bloodmeal host. Additionally, we tested for the presence of flaviviruses in all mosquito samples with RT-PCR. Based on the identity and quantity of detected bloodmeals, we performed mosquito-vertebrate interaction network analysis and estimated topology metrics. In total, we collected 292 engorged female mosquitoes representing 20 different species. Bloodmeal analyses identified 26 vertebrate species, the majority of which were mammals (N = 16; 61.5%). No flaviviruses of medical importance were detected from the samples. Although feeding patterns varied, network analyses showed a high degree of specialization by mosquitoes and revealed ecological and phylogenetic relationships among the host community. We conclude that host selection or preference by mosquitoes is species specific.
Metabolic rare diseases present a serious clinical manifestation causing several problems such as mental retardation, liver damage, hepatocarcinoma and even death without a diagnosis in the first ...days of life. Additionally, there is not any final treatment for these diseases but a dietary restriction, so patients have to control their biomarkers level during their whole life. Current methods for diagnosis and monitoring are tedious, very time-consuming, not portable and need high amount of sample, so they are not suitable for a point-of-care (POC) application. In this sense, electrochemistry presents the required characteristics to be used as POC for metabolic rare diseases. Specifically, this review explores the current methods for amino acids and carbohydrates sensing as biomarkers of metabolic rare diseases using electrochemical (bio)-sensing approaches, especially those based on nanomaterials in both, off and on-chip detection, as well as their suitability in metabolic rare diseases diagnosis and monitoring using clinical samples.
•Nanomaterial-based electrochemical (bio)-sensing for rare diseases diagnostics.•Smart diagnostic tools based exclusively on nanomaterials.•Electrochemical-based POC for metabolic rare diseases diagnosis and monitoring.
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► Visual detection based gold and silver nanoparticles aggregation. ► Functionalized and non-functionalized nanoparticles. ► High selectivity and sensitivity. ► No complex ...instrumentation is required/chemical creativity for analyte detection.
Localized surface plasmon resonance (LSPR) is one of the most remarkable features of gold nanoparticles (Au NPs) and silver nanoparticles (Ag NPs). Due to these inherent optical properties, colloidal solutions of Au and Ag NPs have high extinction coefficients and different colour in the visible region of the spectrum when they are well-spaced in comparison with when they are aggregated. Therefore, a well-designed chemical interaction between the analyte and NPs surroundings leads to a change of colour (red to blue for Au NPs and yellow to brown for Ag NPs from well-spaced to aggregated ones, respectively) allowing the visual detection of the target analyte.
These approaches have exhibited an excellent analytical performance with high sensitivities due to the strong LSPR and excellent selectivity strategically driven by the interaction analyte-NPs surroundings involving mainly electrostatic and hydrogen bond interactions as well as donor–acceptor chemical reactions, among others. In addition, this kind of colorimetric assays has received considerable attention in the analytical field because of their simplicity and low cost since they do not require any expensive or complex instrumentation. As a consequence of this, detection of molecules with a high significance in the bio-medical, clinical, food safety and environmental fields including DNA, proteins and a wide spectrum of organic molecules as well as inorganic ions have been impressively reported in the most relevant literature using these assays.
This timely review offers a rational vision of the main achievements yielded in the relevant literature according to this exciting and creative analytical field.
•Nanoparticles and antioxidants: chemistry for assessing antioxidant capacity.•Synthesis of nanoparticles for evaluating total antioxidant capacity.•Chemistry on nanoparticles for selective detection ...of target antioxidants.
The current review describes the creative use of metallic nanoparticles (mostly gold and silver) and quantum dots as novel tools for reliable assessment of antioxidant activity in food and biological samples. Since evaluation of antioxidant capacity is a complex issue, these nanomaterials emerge as novel, simple and inexpensive tools in the field, becoming not only a valuable alternative to classical approaches but also a complementary one.
Novel single-walled carbon nanotube press-transfer electrodes (SW-PTEs) for microfluidic sensing are proposed. In this approach, carbon nanotubes are press-transferred on poly(methyl methacrylate) ...(PMMA) substrates and are easily coupled to microfluidic chips and act as the exclusive transducer in electrochemical sensing. The detector design consisted of a press-transferred SW film (7 mm × 1 mm) positioned and centered on the PMMA substrate (33 mm × 9 mm). The analytical performance of the SW-PTEs was deeply evaluated using two commercial SWs sources and employing a mixture of dopamine and catechol as model analytes. Analyte detection was influenced by the volume of commercial SW dispersion used in the fabrication of SW-PTEs, with 5 mL taken from a dispersion of 0.5 mg/100 mL being the most favorable volume. In addition, excellent repeatability (relative standard deviation (RSD) of ≤7%, n = 5), interelectrodes reproducibility (RSD ≤ 9%, n = 5), and an extreme resistance to fouling were obtained even after 1 h of microchip analysis with RSD values of ≤4% and ≤9% (n = 15) for migration times and peak heights, respectively. Good sensitivity, remarkable signal-to-noise characteristics, and a well-defined linear concentration dependence (r ≥ 0.990) was also obtained, which allowed these novel detectors to be considered as valuable tools for quantitative analysis. Analytical characterization of the SW-PTEs by field-emission scanning electron microscopy (FESEM) revealed individual bundles of SWs that were highly ordered over the PMMA at the background where the SW bundles were embedded on the PMMA substrate, giving the electrode a high stability. Furthermore, the laboratory-fabricated SW-PTEs can be afforded in any laboratory since they do not require clean-room facilities and are highly compatible with microfluidic scale, mass production, and disposability. In addition, the proposed approach draws new and exciting horizons for electrochemical microfluidic sensing, such as the use of other pure or hybrid nanomaterials and also the possibilities to incorporate biomolecules for highly selective sensing.
Agricultural and Food Electroanalysis offers a comprehensive rationale of electroanalysis, revealing its enormous potential in agricultural food analysis. A unique approach is used which fills a gap ...in the literature by bringing in applications to everyday problems. This timely text presents in-depth descriptions about different electrochemical techniques following their basic principles, instrumentation and main applications. Such techniques offer invaluable features such as inherent miniaturization, high sensitivity and selectivity, low cost, independence of sample turbidity, high compatibility with modern technologies such as microchips and biosensors, and the use of exciting nanomaterials such as nanoparticles, nanotubes and nanowires. Due to the advantages that modern electroanalytical techniques bring to food analysis, and the huge importance and emphasis given today to food quality and safety, this comprehensive work will be an essential read for professionals and researchers working in analytical laboratories and development departments, and a valuable guide for students studying for careers in food science, technology and chemistry.
The use of genetically modified varieties tolerant to herbicides (HT varieties) and resistant to insects (Bt varieties) in combination with application of a broad‐spectrum herbicide such as ...glyphosate could be an effective option for the simultaneous control of weeds and pests in maize. Nevertheless, the possible impact of these tools on nontarget arthropods still needs to be evaluated. In a field study in central Spain, potential changes in populations of canopy‐dwelling arthropods in Bt maize under different weed management options, including glyphosate application, were investigated. Canopy‐dwelling arthropods were sampled by visual inspection and yellow sticky traps. The Bt variety had no effect on any group of studied arthropods, except for the expected case of corn borers—the target pests of Bt maize. Regarding the effects of herbicide regimes, the only observed difference was a lower abundance of Cicadellidae and Mymaridae on yellow sticky traps in plots not treated with pre‐emergence herbicides. This effect was especially pronounced in a treatment involving two glyphosate applications. The decrease in Cicadellidae and Mymaridae populations was associated with a higher density of weeds in plots, which may have hindered colonization of the crop by leafhoppers. These differences, however, were only significant in the last year of the study. The low likelihood of the use of glyphosate‐ and herbicide‐tolerant varieties for weed control triggering important effects on the nontarget arthropod fauna of the maize canopy is discussed.
Endoxylanases belonging to family 10 of the glycoside hydrolases (GH10) are versatile in the use of different substrates. Thus, an understanding of the molecular mechanisms underlying substrate ...specificities could be very useful in the engineering of GH10 endoxylanases for biotechnological purposes. Herein, we analyzed XynA, an endoxylanase that contains a (β/α)
-barrel domain and an intrinsically disordered region (IDR) of 29 amino acids at its amino end. Enzyme activity assays revealed that the elimination of the IDR resulted in a mutant enzyme (XynAΔ29) in which two new activities emerged: the ability to release xylose from xylan, and the ability to hydrolyze
-nitrophenyl-β-d-xylopyranoside (pNPXyl), a substrate that wild-type enzyme cannot hydrolyze. Circular dichroism and tryptophan fluorescence quenching by acrylamide showed changes in secondary structure and increased flexibility of XynAΔ29. Molecular dynamics simulations revealed that the emergence of the pNPXyl-hydrolyzing activity correlated with a dynamic behavior not previously observed in GH10 endoxylanases: a hinge-bending motion of two symmetric regions within the (β/α)
-barrel domain, whose hinge point is the active cleft. The hinge-bending motion is more intense in XynAΔ29 than in XynA and promotes the formation of a wider active site that allows the accommodation and hydrolysis of pNPXyl. Our results open new avenues for the study of the relationship between IDRs, dynamics and activity of endoxylanases, and other enzymes containing (β/α)
-barrel domain.
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