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Bone morphogenetic proteins (BMPs) belong to the TGF-β superfamily of signaling ligands which comprise a family of pluripotent cytokines regulating a multitude of cellular events. Although BMPs were originally discovered as potent factors extractable from bone matrix that are capable to induce ectopic bone formation in soft tissues, their mode of action has been mostly studied as soluble ligands in absence of the physiologically relevant cellular microenvironment. This micro milieu is defined by supramolecular networks of extracellular matrix (ECM) proteins that specifically target BMP ligands, present them to their cellular receptors, and allow their controlled release. Here we focus on functional interactions and mechanisms that were described to control BMP bioavailability in a spatio-temporal manner within the respective tissue context. Structural disturbance of the ECM architecture due to mutations in ECM proteins leads to dysregulated BMP signaling as underlying cause for connective tissue disease pathways. We will provide an overview about current mechanistic concepts of how aberrant BMP signaling drives connective tissue destruction in inherited and chronic diseases.

Since their discovery as pluripotent cytokines extractable from bone matrix, it has been speculated how bone morphogenetic proteins (BMPs) become released and activated from the extracellular matrix (ECM). In contrast to TGF-βs, most investigated BMPs are secreted as bioactive prodomain (PD)-growth factor (GF) complexes (CPLXs). Recently, we demonstrated that PD-dependent targeting of BMP-7 CPLXs to the extracellular fibrillin microfibril (FMF) components fibrillin-1 and -2 represents a BMP sequestration mechanism by rendering the GF latent. Understanding how BMPs become activated from ECM scaffolds such as FMF is crucial to elucidate pathomechanisms characterized by aberrant BMP activation and ECM destruction. Here, we describe a new MMP-dependent BMP-7 activation mechanism from ECM-targeted pools via specific PD degradation. Using Edman sequencing and mutagenesis, we identified a new and conserved MMP-13 cleavage site within the BMP-7 PD. A degradation screen with different BMP family PDs and representative MMP family members suggested utilization of the identified site in a general MMP-driven BMP activation mechanism. Furthermore, sandwich ELISA and solid phase cleavage studies in combination with bioactivity assays, single particle TEM, and in silico molecular docking experiments provided evidence that PD cleavage by MMP-13 leads to BMP-7 CPLX disintegration and bioactive GF release.

The effects of montmorillonite (MMT) treatment with supercritical carbon dioxide (SC-CO2) on clay morphology and the properties of polypropylene nanocomposites were investigated by wide-angle X-ray diffraction, transmission electron microscopy, scanning electron microscopy, dynamic mechanical analysis, and differential scanning calorimetry. The use of poly(propylene glycol) (PPG) was evaluated. The results showed that the MMT morphology (structure formation, dispersion, and orientation) was affected by treatment with SC-CO2, and the use of PPG, or the use of CO2 in the liquid state. Consequently, different reinforcement measurements were obtained. The relationship between structure and properties was reported.

RESUMO Atrazine é um herbicida recomendado para a cultura do milho, porém há poucas informações sobre seu efeito residual em hortaliças que eventualmente poderão ser cultivadas em sucessão. O objetivo dessa pesquisa foi avaliar a simulação do residual de subdoses de atrazine no substrato sobre o desenvolvimento e produção de cenoura 'Brasília'. Os tratamentos constituíram-se de oito doses decrescentes de atrazine (250, 25,0, 2,5, 0,25, 0,025, 0,0025, 0,00025 e 0 g i.a./ha) partindo da concentração de 1/10 da dose recomendada comercialmente para a cultura do milho doce (2500 g i.a./ha). O delineamento experimental foi inteiramente casualizado com quatro repetições. As unidades experimentais foram constituídas de vasos de plástico com capacidade de 20 L. As plantas de cenoura foram avaliadas quanto à porcentagem e índice de velocidade de emergência (aos 7, 14 e 21 dias após a aplicação), taxa de mortalidade, perímetro e comprimento de raiz, massa fresca de raiz e massa seca de parte aérea aos 29 e 90 dias após a aplicação (DAA). Concluiu-se que residual de até 250 g i.a/ha de atrazine pode causar redução na biomassa inicial da cenoura (29 DAA), sem, no entanto, prejudicar sua produção de raízes. ABSTRACT Atrazine is an herbicide recommended for the corn crop, but little information is available on its residual effect on vegetables that could be grown in succession. The objective of this research was to evaluate the residual simulation of atrazine doses in the substrate on the development and production of 'Brasília' carrot. Treatments consisted of eight decreasing doses of atrazine (250, 25.0, 2.5, 0.25, 0.025, 0.0025, 0.00025 and 0 g a.i./ha) starting on 1/10 of the concentration dose commercially recommended for sweet corn (2500 g a.i./ha). Experimental design was completely randomized with four replications. Experimental units consisted of plastic pots with a capacity of 20 L. The carrot plants were evaluated for percentage and emergence speed index (at 7, 14 and 21 days after application), mortality, length and perimeter of roots, root fresh weight and dry weight of aboveground part at 29 and 90 days after application (DAA). We concluded that residual up to 250 g a.i./ha atrazine might cause initial biomass reduction in carrot (29 DAA), without, however, damaging its production of roots.

Polypropylene montmorillonite (PP–MMT) nanocomposites have been prepared by using a co-rotating twin screw extruder. The effects of processing conditions at fixed clay content (5 wt%) on polymer properties were investigated by means of transmission electron microscopy (TEM), flexural modulus, izod impact, dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC). It was noticed that the morphology and the mechanical properties of polypropylene nanocomposites were affected by different screw shear configuration. The results showed that the higher enhancement on mechanical properties was obtained by medium shear intensity profile instead of high configuration. An exceptional increase (maximum of 282%) on impact resistance was observed.

Summary: The performances of readily available Ln(allyl)2Cl(MgCl2)2 · (THF)4 precursors (Ln = Nd, 1; Y, 2; La, 3), in combination with alkyl aluminum activators [MAO, AlMe3, AlEt3, Al(iBu)3], have been studied in isoprene polymerization. The catalyst combination 1/MAO (1:30) shows a high activity (average TOFs up to ca. 5 × 104 mol (Ip) · mol (Nd)−1 · h−1 at 20 °C) and produces polyisoprene in a controlled fashion with up to 98.5% cis content, number-average molecular weights in reasonable agreement with calculated values, and relatively narrow polydispersities index ( = 1.20–1.70). The yttrium precursor 2 affords systems with much lower activity and degree of control, but enables the formation of either 1,4-cis-enriched (75%) or 1,4-trans-enriched (91%) polyisoprenes, simply replacing the MAO activator by AlEt3 or Al(iBu)3, respectively. Formation of 1,4-cis- or 1,4-trans-enriched polyisoprenes upon activation with MAO.

Linear low density polyethylene (LLDPE) with different branching contents were prepared from ethylene, without the addition of α-olefin comonomer, using a combination of catalyst precursors {TpMs}NiCl (1) (TpMs = hydridotris(3-mesitylpyrazol-1-yl)) and Cp2ZrCl2 (2) activated with MAO/TMA (1:1) in toluene at 0 °C and by varying the nickel loading mole fraction (xNi). The polymerization results showed that the turnover frequencies are strongly dependent on the xNi varying from 6.6×103 to 32.1×103 mol[C2H4]/mol[Zr] h. The 13 C NMR spectra of the copolymers showed that the branch contents of the polymers increase as the xNi increase in the medium promoting the production of polymers with a wide range of melting point (Tm).

The synthesis and characterization of the novel zirconium (IV) tris(pyrazolyl)borate compound {TpMs*}ZrCl3 (1) (TpMs* = hydridobis(3-mesitylpyrazol-1-yl)(5-mesitylpyrazol-1-yl)), as well as its performance in polymerizing ethylene are described. The reaction of ZrCl4 with 1 equivalent of TlTpMs* in toluene at room temperature affords 1 as a white solid in 62% yield. Compound 1 in the presence of MAO showed remarkable productivity using a low Al : Zr molar ratio (6.79×104 kg of PE/(mol Zr·h·[C2H4]); toluene, 60°C, Al/Zr = 100). Under identical polymerization conditions, compound 1 and Cp2ZrCl2 showed comparable productivities. Compound 1 displayed similar productivities at temperatures in the range of 0–75°C and noticeable productivity at 105°C. The viscosity-average molecular weight of the polyethylenes depends on the Al : Zr molar ratio and polymerization temperature and varied between 1.09 and 8.98×105 g·mol–1.

Carrier density profile determinations are reported which confirm that a mass action relation holds between the ionized and the inactive mobile As in silicon. Experiments were performed under equilibrium conditions at temperatures in the range 780–885°C. The carrier density n versus the dopant concentration N T exhibits a very pronounced saturation behaviour which is compared with the one expected in well known cluster models. These results complement the recent finding that the inactive As can exist in equilibrium with the monoclinic SiAs. From this information and previous SAXS, TEM, and EXAFS results one can conclude that a pre-precipitation phenomenon, with its inherent cluster distribution, is responsible for the inactive As.

This study examined the effect of whole oat consumption in the oxidative stress induced by exercise in rats. The activity of antioxidant enzymes (catalase [CAT] and glutathione peroxidase [GSH-Px]), lipid peroxidation by the measurement of thiobarbituric acid reactive substances in blood and plasma and also the total antioxidants (Trolox equivalent antioxidant capacity) present in plasma were available. The animals submitted to a swimming exercise program for 15 days, which did not receive the oats, showed an increase in CAT level, while the animals that were fed the modified diet did not show the same increase. No differences were observed in GSH-Px and lipid peroxidation between groups. Antioxidant capacity was higher in the plasma of animals that were fed with the modified diet. This study indicates that whole oat supplementation may be beneficial against the oxidative stress induced by exercise. Pratical applications Currently, many people have been ingesting polyphenolic dietary supplements in an attempt to avoid free radical damage which has been linked to the aging process and some degenerative diseases. Among other factors, these free radicals are produced in the body during physical exercise. This work demonstrates that the inclusion of whole oats in the diet can contribute to prevention of oxidative damage caused by acute exercise-induced oxidative stress.

This article describes the application of ionic liquid 1-decyl-3-methylimidazolium tetrafluoroborate in the preparation of polypropylene-silica composites. The sol-gel technology was used to prepare xerogel silica-ionic liquid hybrid S1, which was obtained as a free flowing powder of aggregated spherical particles. Ionic liquid free silica S2 was obtained by extraction and calcination of S1. Melt blending of isotactic polypropylene with S1 and S2 afforded the composites C1 (with ionic liquid) and C2 (without ionic liquid), respectively. The presence of ionic liquid on the S1 silica surface promoted significantly improved silica dispersion in the polymer matrix and prevented compression of the silica particles. Furthermore, the crystallization temperature of composite C1 was significantly higher, which indicated that silica-ionic liquid filler S1 acted as nucleating agent. The resistance to thermal decomposition of both composites was increased, but this was higher in the presence of ionic liquid. These results show that liquid salts can function as coupling agents and compatibalizers for the preparation of polymeric composites with differentiated properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Branched polyethylene/high-density polyethylene blends (BPE/HDPE) were prepared using the combined [NiCl2(alpha-diimine)] (1) (alpha-diimine = 1,4-bis(2,6-diisopropylphenyl)-acenaphthenediimine) and [TpMs*VCl2(NtBu)] (2) (TpMs* = hydridobis(3-mesitylpyrazol-1-yl)(5-mesitylpyrazol-1-yl)) catalysts. The polymerization reactions were performed in hexane or toluene at three different polymerization temperatures (0, 30 and 50 °C) and several nickel molar fractions (xNi), using MAO as cocatalyst. At all temperatures, the activities show an approximate linear correlation with xNi, indicating a non-synergistic effect between the nickel and the vanadium species. Higher activities were found in toluene at 0 °C. The melting temperatures for the polyethylene blends produced at 0 °C decrease as xNi increases in the medium indicating good miscibility between the polyethylene phases made by both catalysts. The surface morphology of the BPE/HDPE blends studied by scanning electron microscopy (SEM) revealed low miscibility between the PE phases mainly in the case of the polymer blends produced at high temperature (50 ºC). Blendas de polietileno ramificado/polietileno de alta densidade (BPE/HDPE) foram preparadas usando uma combinação de catalisadores [NiCl2(diimina-alfa)] (1) (diimina-alfa = 1,4-bis(2,6-diisopropilfenila)-acenafeteno) e [TpMs*VCl2(NtBu)] (2) (TpMs* = hidridobis(3-mesitilapirazol-1-il)(5-mesitilapirazol-1-il)). As reações de polimerização foram realizadas em hexano ou tolueno em três diferentes temperaturas (0, 30 e 50 °C), utilizando várias razões molares de níquel (xNi), na presença de metilaluminoxano (MAO) como cocatalisador. Em todas as temperaturas, as atividades mostraram uma correlação aproximadamente linear com xNi, indicando o não aparecimento de um efeito sinérgico entre as espécies de níquel e vanádio. Altas atividades foram obtidas a 0 °C. As temperaturas de fusão (Tm) das blendas de polietileno produzidas a 0 °C diminuem conforme a xNi aumenta no meio reacional, indicando uma boa miscibilidade entre as fases de polietileno produzidas por ambos catalisadores. A morfologia da superfície das blendas de BPE/HDPE estudadas por microscopia eletrônica de varredura (MEV) revelou uma baixa miscibilidade entre as fases de PE, principalmente no caso das blendas poliméricas produzidas a alta temperatura (50 ºC).

DNA analysis by PCR-based polymorphisms is routinely carried out in the forensic laboratory. The most relevant advantage of the in vitro amplification is the high sensitivity of this technique that permits successful characterisations from nanograms of (also degraded) DNA samples (Bloch, 1991; Reynolds and Sensabaugh, 1991).

The purpose of this study was to determine the amount of selenium in serum of an Italian population of 143 subjects. Data suggest that an adequate amount of selenium is consumed in the diet, since the level of selenium concentration in the blood is normal (70.7 μg/1), A correlation coefficient of 0.82 (p

We review classical solutions, both of the instanton and meron type, for the nonlinear σ-model in two dimensions and discuss their generalization to the four-dimensional case, which involves a fourth-order derivative Lagrangian.

The synthesis of γ-phenyl and γ-( n -pyridyl)paraconates was accomplished by chemical reduction of their respective ketodiester precursors followed by cyclisation of the resulting hydroxy diester intermediates. The cis - and trans -lactones thus obtained were separated and separately subjected to enzymatic hydrolysis with HLAP. The cis -lactonic esters had enantiomeric excesses ranging from 94% to 99%, while for the trans -isomers the ee’s ranged from 80% to 93%. The same ketodiester precursors were subjected to reduction with a series of yeasts. The absolute configuration of trans -(−)-2-pyridyl paraconic acid was assigned by means of X-ray analysis of its hydrobromide salt, while the absolute configurations of the other lactones were determined via analysis of their respective CD curves.

Enantioselective deacetylation of a-(±)-botryodiplodin acetate was successfully accomplished by means of lipase PS to afford (+)-botryodiplodin and a-(+)-botryodiplodin acetate with high enantiomeric excesses. Enzyme-mediated transesterification of the acetylated molecule with n-butanol, as well as its hydrolysis in several organic solvents, are also reported. The CD spectra of (+)-botryodiplodin and a-(+)-botryodiplodin acetate are also presented.

Enantiopure cis- and trans-4-methylparaconic acids and their alkyl esters were synthesized by a procedure involving the kinetic enzymatic resolution of diastereomeric lactonic esters. Thus, ethyl cis- and trans-4-methyl-5-oxo-tetrahydrofuran-3-carboxylates were isolated, at high conversion values, with 99% ee from the hydrolyses with HLAP and a-CT, respectively. The corresponding enantiopure cis- and trans-lactonic acids were also obtained. The absolute configurations of the products were assigned by chemical correlation, by analysis of their circular dichroism spectra and by electronic structure calculations. All three methodologies lead to the same assignment for the species considered, another example of successful interplay between experiment and theory.