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In the present work, magnetic nanoparticles coated with silica or ORMOSIL are prepared in a two step process. In the first step, SPIONs with 6 nm average diameter are produced by a reduction-precipitation process conducted in air and in the second one, SPIONs were used as seeds for silica/ORMOSIL growth (below 30 nm), in situ by a modified Stober sol-gel method. SPIONs and silica/ ORMOSIL magnetic core-shell nanostructures were characterized by X-Ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), Mossbauer spectroscopy and SQUID magnetometry. TEM observations of SPIONs and silica/ORMOSIL SPIONs allow determining size and shape. FTIR allows determining silica/ORMOSIL structural fingerprints. X-ray and Mossbauer spectroscopy allow determining the magnetite/maghemite ratio, discussed as a nanosized constrained. SPIONs and silica/ORMOSIL SPIONs show superparamagnetic properties making them appropriated to biomedical applications.

A patologia respiratória é relativamente frequente durante a gravidez. Um terço das grávidas sofrem exacerbação da asma. O tromboembolismo pulmonar é cerca de 5 vezes mais frequente na gravidez. As pneumonias bacterianas, virais e fúngicas são mal toleradas pela grávida, provocando significativa morbilidade materno-fetal, insuficiência respiratória, baixo peso ao nascer ou prematuridade. A tuberculose, se não for tratada, pode aumentar em 4 vezes a mortalidade materna e em 9 vezes o parto pré-termo. A gravidez está contra-indicada em mulheres com fibrose quística e função pulmonar grave. Apesar dos progressos terapêuticos, a hipertensão pulmonar continua a estar associada a valores superiores a 30% de morbilidade e mortalidade materno-fetal. Aproximadamente 1 em 1000–1500 gravidezes é complicada por neoplasia maligna materna. O cancro do pulmão nas grávidas coloca desafios terapêuticos importantes devido às elevadas taxas de mortalidade.

Here we describe extracellular matrix alterations in footpad lesions and draining lymph nodes caused by Leishmania (L.) amazonensis in mouse strains with distinct susceptibilities to this parasite: BALB/c (susceptible), C57BL/6 (intermediate), and DBA/2 (resistant). Changes in ECM were observed mainly in BALB/c mice that, in general, presented tissue damage associated with high parasite burden. Under polarized light, Sirius Red revealed type I collagen that was predominant in the primary lesion in all strains studied at the early phase of infection, but gradually decreased and was replaced by abundant type III collagen fibres in chronic phase lesions. The presence of type III collagen seemed to provide support to inflammatory cells, mainly vacuolated and parasitized macrophages. Laminin expression was not altered during infection by L. (L.) amazonensis in any of the mouse strains studied. Furthermore, the decreased fibronectin expression, in all strains, in areas where amastigotes have been found, indicated that this decline was also not related to the genetic background.

In Ochroma pyramidale(Cav. exLam.) Urb., photon-saturated photosynthetic capacity (PNmax) was 13 μmol(CO2) m−2s−1. Average stomatal conductance (gs) and water-use efficiency (WUE) were greater at high irradiance, about 260 mmol(H2O) m−2s−1and 2.15 g(C) kg−1(H2O), respectively. In the dark, gsvalues were about 30% of maximum gs. Leaf nutrient contents on a leaf area basis were 131, 15, 36, 21, and 12 mmol m−2for N, P, K, Ca, and Mg, respectively. Ochromaalso accumulated a greater amount of soluble saccharides than starch, 128 versus90 g kg−1(DM). The availability of N and Mg, but not P, Ca, or K, may limit photosynthetic rates of Ochromain this site.

The reproducibility of measurements performed with GR-100 (LiF:Mg,Ti) from the Solid Dosimetric Detector and Method Laboratory (DML) China, GR-107 (7LiF:Mg,Ti, DML), TLD-700H (7LiF:Mg,Cu,P, Harshaw) and Al2O3:Mg,Y (Hungary) in photon and mixed photon-neutron fields was investigated. Mixed-field irradiations were performed in a thermal neutron field generated at a nuclear reactor. GR-100 sensitivity decreased after mixed-field irradiations, while no significant change was found for the other materials. Using GR-100 for the dosimetry of mixed and high-intensity fields requires careful procedures.

Maps of polarization and anisotropy can be helpful for flow analysis systems (FIA, CFA, etc.) with reactions dependent on the intermolecular alignment as well as for dispersion control. Maps can be acquired manually, but when a scan over a sample area is required, the acquisition becomes tiresome and has low precision. The paper describes an automatic flexible system for high-precision sample positioning with closed loop self control, remote data acquisition and storage controlled by a BASIC program. The system was developed to acquire maps up to 850 mm2 of the sample (liquid flows, solids, interfaces, etc.), with up to 100 µm2 precision. To evaluate the equipment, performance is presented as the scan of a thin liquid film of monoethylene glycol (MEG) flowing on borosilicate. Tests were performed with and without surfactantes at submicellar concentrations: two concentrations of sodium dodecyl sulphate (SDS) and one of polyethylene oxide (PEO). For pure MEG, the intermolecular alignment initially increased, then decreased. When SDS was added, both polarization and anisotropy only increased progressively with the flow. This might be explained by the surfactant decrease of interfacial interaction. When PEO was added, both polarization and anisotropy decreased pronouncedly over the entire map, which might be due to macromolecular aggregates within the bulk generating misaligned molecular domains. The system presented as sample positioning repeatability of 0.1% and a high polarization reproducibility (error margin < 6 in 1000).

The injection of Crotalus durissus terrificus venom into the foot pad of mice did not induce a significant inflammatory response as evaluated by oedema formation, increased vascular permeability and cell migration. The subcutaneous injection of the venom, or its addition to cell cultures, had an inhibitory effect on the spreading and phagocytosis of resident macrophages, without affecting the viability of the cells. This effect was not observed when the venom was added to cultures of thioglycollate elicited macrophages, but it was able to inhibit these macrophage functions when the cells were obtained from animals injected simultaneously with the venom and thioglycollate. These observations suggest that the venom interferes with the mechanisms of macrophage activation. Leukocyte migration induced by intraperitoneal injection of thioglycollate was also inhibited by previous venom injection. This down-regulatory activity of the venom on macrophage functions could account for the mild inflammatory response observed in the site of the snake bite in Crotalus durissus terrificus envenomation in man.