A criança na constituição cultural, sociopolítica e educativa dos assentamentos de reforma agrária: negações e conquistas

Se a infância não pode ser pensada enclausurada na dimensão cronológica, mais ainda a infância campesina não pode ser concebida reduzidamente. As crianças de assentamentos crescem envoltas na incerteza da posse da terra, se educam na luta, cedo aprendem que a organização coletiva é um caminho para vitória e, ao mesmo tempo, é meio de resistência. O objetivo, para este trabalho, foi o de analisar, através das narrativas orais, os processos de constituição das infâncias campesinas, numa escola no assentamento de Reforma Agrária, em Santaluz, BA. A etnografia visual foi a metodologia que conduziu a investigação, possibilitando o uso variado de técnicas para a construção das análises. Elegemos ainda uma ação interativa, denominada Poteca, desencadeadora das narrativas orais das crianças, famílias e professora. A partir do movimento teórico-conceitual, ampliamos o olhar para a constituição das crianças nos planos sociais, educativos, culturais e políticos. É preciso também perceber que o contexto de luta cotidiana contra o preconceito e a criminalização faz surgir uma dinâmica de produção e autoprodução em que essas crianças se constituem, vivem suas infâncias e afirmam-se como um coletivo culturalmente organizado e produtivo. Essas percepções basearam-se nas histórias narradas durante a investigação, por meio das interações proporcionadas pela Poteca. As experiências orais, após serem registradas, sistematizadas e analisadas, poderão subsidiar as práticas pedagógicas e a construção de currículos que considerem as concepções, os conhecimentos, as culturas e os valores oriundos dos movimentos sociais

Metodutveckling för analys av serglycinuttrycket i blodet hos hundar

The development of quantitative, real-time PCR (qPCR) combined with the mapping of the canine genome opens new possibilities in veterinary medicine. This method provides a quick and accurate quantification of the expression of a specific gene at a given point in time and thereby also information of how the gene expression for a certain protein is influenced by various conditions and diseases. One possible area of application is identifying bio markers for cancer. Recently the protein serglycin (the core protein of an intracellular proteoglycan) was found to act as a selective marker for the disease acute myeloid leukemia in humans (Niemann et al, 2007). Serglycin is produced by most hematopoietic cells, although mast cells account for the largest amount of serglycin. The expression of serglycin in dogs remains to be explored. As mast cell tumours are common in this species, it would be of interest to find out whether serglycin can be used as a marker for these tumours, to facilitate diagnosis and prognosis as well as evaluation of how well a patient is responding to treatment. The aim of this study is to develop a qPCR-analysis of serglycin expression in canine blood, to serve as a starting point for further research. Several parameters, such as the optimum temperature for the PCR-reaction, primer design and DNA-concentration, have been established. The resulting PCR-analysis is functioning, although still in need of further modifications in order to achieve the desired efficiency and reproducibility.Utvecklandet av kvantitativ, direktanalyserad PCR (qPCR, realtidsPCR) öppnar tillsammans med kartläggningen av hundens genom nya möjligheter inom veterinärmedicinen. Med denna metod kan man snabbt och noggrant kvantifiera uttrycket av en specifik gen och på så vis få information om hur genuttrycket för ett visst protein påverkas vid olika tillstånd. Ett möjligt användningsområde är att identifiera biomarkörer för olika cancersjukdomar. Nyligen konstaterades proteinet serglycin (som utgör kärnan i en intracellullär proteoglykan) vara en selektiv markör för sjukdomen akut myeloid leukemi hos människa (Niemann et al, 2007). Serglycin förekommer hos flertalet hematopoietiska celler, dock svarar mastcellerna för den högsta produktionen. Till min vetskap har serglycinuttrycket hos hund ännu ej studerats. Eftersom mastcellstumörer är vanliga hos detta djurslag vore det intressant att ta reda på om serglycin kan användas som biomarkör för dessa, att användas såväl prognostiskt och diagnostiskt som för uppföljning av insatt behandling. Syftet med detta arbete är att utveckla en qPCR-analys av serglycinuttryck i hundblod som kan ligga till grund för fortsatta studier. Olika parametrar, såsom optimal temperatur för PCR-reaktionen, primerdesign och DNA-koncentration, har fastslagits. Slutresultatet blev en fungerande qPCR-analys för hundserglycin, som dock behöver ytterligare modifieringar för att uppnå önskad effektivitet och reproducerbarhet

Microwave-assisted synthesis of surface-enhanced Raman scattering nanoprobes for cellular sensing

The fabrication of 4-mercaptobenzoic acid (4-MBA) antibody-functionalized gold nanoparticles via microwave technology for surface-enhanced Raman scattering (SERS)-based cellular nanosensing is reported. Nanoprobes were characterized by UV–vis absorbance, Raman scattering properties, and observed by TEM imaging. Results showed that microwave irradiation rapidly yielded nanoprobes with significant Raman scattering intensity and suitable stability to support antibody conjugation in under 10 min. Functionalized nanoprobes demonstrated the ability to map the expression of vascular adhesion molecule-1 (VCAM-1) in human coronary artery endothelial (HCAE) cells, indicating that microwave fabrication presents a viable and rapid approach to SERS nanoprobe construction. The successful application of SERS nanoprobes to localize biomarker expression in vitro may ultimately be used for early diagnostic and preventative functions in medicine

Zeptomole Detection of C-Reactive Protein in Serum by a Nanoparticle Amplified Surface Plasmon Resonance Imaging Aptasensor

Diagnostic biomarkers (i.e. proteins) are often in low abundance in bodily fluids presenting many challenges for their detection. In order to extend the application of SPRi systems in detecting biomarkers at ultralow levels, we combine the advantage of aptamer technology with nanomaterials and microwave-assisted surface functionalization. By implementing a sandwich assay through the introduction of aptamer-modified quantum dots (QDs), it was possible to measure 7 zeptomole (at 5 fg/mL) of C-reactive protein (CRP) selectively in spiked human serum. It is expected that the proposed platform will provide new direction in designing ultrasensitive SPRi biosensors with multiplexing capabilities

Self-assembled Multifunctional Nanoplexes for Gene Inhibitory Therapy

Aim: To enhance the stability of siRNA while improving their therapeutic properties and visualization at the target site, a novel nanoplex system was developed. Materials & Methods: The designed nanoplex system involved functionalizing siRNA with near-infrared quantum dots and loading them into histidylated glycol chitosan (GC-His). Results: Colocalization studies revealed a twofold increase in siRNA uptake after encapsulation with GC-His and nanoparticles were localized in cytoplasm, suggesting that histidine promoted their dissociation from the endosomal membranes. Furthermore, as opposed to siRNAs treated with commercial transfection reagent, siRNAs loaded within GC-His showed a marked reduction (64%) of MDM2 protein expression 24 h after transfection. Conclusion: These findings concur that GC-His/siRNA-quantum dot nanoplexes are promising multifunctional vehicles for gene inhibitory therapy

Imaging and Organelle Distribution of Fluorescent InGaP/ZnS Nanoparticles in Glial Cells

Aim: To assess the effects of oleic acid treatment on subcellular distribution of indium gallium phosphide–zinc sulfide (InGaP/ZnS) nanoparticles in microglia and astrocytes. Materials & methods: The extent of colocalization between the nanoparticles and organelles was assessed by confocal microscopy, spectrofluorometry and cell sorting. Results: Cell treatment with a common fatty acid (oleic acid) within the range of physiological concentrations markedly enhanced the InGaP/ZnS uptake by microglia and afforded their colocalization within lipid droplets/lysosomes but not with mitochondria. Conclusion: These results suggest that the availability of mono-unsaturated fatty acids, such as oleic acid, in different cells could significantly alter nanoparticle uptake and localization, which can in turn affect the functions of cells and tissues coexposed to nanoparticles

Effects of Novel Nanomaterials on Allergic Mediator Release from Human Mast Cells and Basophils through Non-Ige Mediated Pathways

Mast cells (MC) and peripheral blood basophils (PBB) are well known for their role in the allergic response mediated through high affinity IgE receptors (FceRI). However, these cells can also be stimulated by other non-allergic secretagogues to release their inflammatory mediators. Certain fullerene derivatives (FD) have already been shown to stabilize FceRI-mediated MC/PBB responses, but it is not know if they also stabilize these cells through non-IgEmediated mechanisms. A panel of FD was synthesized and tested for their ability to inhibit non-FceRI mediated release from human MC and PBB. It was found that specifically engineered FD could significantly inhibit calcium ionophore, compound 48/80, somatostatin, and poly L-lysine induced MC degranulation and cytokine production, as well as blunt degranulation and cytokine production from N-formyl-methionine-leucine-phenylalanine (fMLP), poly L-lysine, and calcium ionophore stimulated PBB. The mechanism of inhibition was due in part to the prevention of secretagogueinduced increases in cellular reactive oxygen species (ROS) and calcium levels as well as the reduced activation of the MAPK signaling intermediates ERK1/ERK2 and LAT. Additionally, preincubation of MC with FD blunted the prostaglandin D2 (PGD2) production upon exposure to inflammatory stimuli. In both cell types, the extent of inhibition of mediator release in response to each secretagogue was dependent on the moieties/side chains attached to the carbon cage. These results further extend the utility of fullerene nanomaterials to control mediator release through non-IgE mediated pathways in MC/PBB

Functionalization of Gadolinium Metallofullerenes for Detecting Atherosclerotic Plaque Lesions by Cardiovascular Magnetic Resonance

Background: The hallmark of atherosclerosis is the accumulation of plaque in vessel walls. This process is initiated when monocytic cells differentiate into macrophage foam cells under conditions with high levels of atherogenic lipoproteins. Vulnerable plaque can dislodge, enter the blood stream, and result in acute myocardial infarction and stroke. Imaging techniques such as cardiovascular magnetic resonance (CMR) provides one strategy to identify patients with plaque accumulation. Methods: We synthesized an atherosclerotic-targeting contrast agent (ATCA) in which gadolinium (Gd)-containing endohedrals were functionalized and formulated into liposomes with CD36 ligands intercalated into the lipid bilayer. In vitro assays were used to assess the specificity of the ATCA for foam cells. The ability of ATCA to detect atherosclerotic plaque lesions in vivo was assessed using CMR. Results: The ATCA was able to detect scavenger receptor (CD36)-expressing foam cells in vitro and were specifically internalized via the CD36 receptor as determined by focused ion beam/scanning electron microscopy (FIB-SEM) and Western blotting analysis of CD36 receptor-specific signaling pathways. The ATCA exhibited time-dependent accumulation in atherosclerotic plaque lesions of ApoE -/- mice as determined using CMR. No ATCA accumulation was observed in vessels of wild type (C57/b6) controls. Non-targeted control compounds, without the plaque-targeting moieties, were not taken up by foam cells in vitro and did not bind plaque in vivo. Importantly, the ATCA injection was well tolerated, did not demonstrate toxicity in vitro or in vivo, and no accumulation was observed in the major organs. Conclusions: The ATCA is specifically internalized by CD36 receptors on atherosclerotic plaque providing enhanced visualization of lesions under physiological conditions. These ATCA may provide new tools for physicians to non-invasively detect atherosclerotic disease

The (6-4) Dimeric Lesion as a DNA Photosensitizer

[EN] Based on our previous investigations into the photophysical properties of the 5-methyl-2-pyrimidone (Pyo) chromophore, we now extend our studies to the photobehavior of the dimeric (6-4) thymine photoproducts (6-4 PP) to evaluate their capability to act as instrinsic DNA photosensitizers. The lesion presents significant absorption in the UVB/UVA region, weak fluorescence emission, a singlet-excited-state energy of approximately 351 kJ mol(-1), and a triplet-excited-state energy of 297 kJ mol(-1). Its triplet transient absorption has a maximum at 420-440 nm, a lifetime of around 7 mu s, and a high formation quantum yield, Phi(ISC) = 0.86. This species is efficiently quenched by thymidine. Its DNA photosensitizing properties are demonstrated by a series of experiments run on a pBR322 plasmid. The lesion photoinduces both single-strand breaks and the formation of cyclobutane thymine dimers. Altogether, these results show that, the substitution of the pyrimidone ring at C4 by a 5-hydroxy-5,6-dihydrothymine does not cancel out the photosensitization properties of the chromophore.Spanish Government (CTQ2015-70164-P, RIRAAF RETICS RD12/0013/0009, Prometeo II program, Severo Ochoa program/SEV-2012-0267 and JAE-Predoc 2011-00740 to V. V.-C.) is gratefully acknowledged.Vendrell Criado, V.; Rodríguez Muñiz, GM.; Lhiaubet ., VL.; Cuquerella Alabort, MC.; Miranda Alonso, MÁ. (2016). The (6-4) Dimeric Lesion as a DNA Photosensitizer. ChemPhysChem (Online). 17(13):1979-1982. https://doi.org/10.1002/cphc.201600154S19791982171

Photosensitized Thymine Dimerization via Delocalized Triplet Excited States

A new mechanism of photosensitized formation of thymine (Thy) dimers is proposed, which involves generation of a delocalized triplet excited state as the key step. This is supported by chemical evidence obtained by combining one benzophenone and two Thy units with different degrees of freedom, whereby the photoreactivity is switched from a clean Paterno-Buchi reaction to a fully chemo-, regio-, and stereoselective [2+2] cycloaddition.Financial support from the Spanish Government (Grants SEV-2012-0267, CTQ2012-38754-C03-03, and CTQ2012-32621), Generalitat Valenciana (Prometeo Program), and Technical University of Valencia (Predoctoral FPI fellowship for P.M.) is gratefully acknowledged.Miró Richart, P.; Lhiaubet, VL.; Marín García, ML.; Miranda Alonso, MÁ. (2015). Photosensitized Thymine Dimerization via Delocalized Triplet Excited States. Chemistry - A European Journal. 21(47):17051-17056. doi:10.1002/chem.201502719S1705117056214