Structural Analysis of the Black-Legged Tick Saliva Protein Salp15

Salp15 is one of the proteins in the saliva of the tick Ixodes scapularis. Together with other biomolecules injected into the mammalian host at the biting site, it helps the tick to sustain its blood meal for days. Salp15 interferes with the cellular immune response of the mammalian host by inhibiting the activation of CD4⁺ T-lymphocytes. This function is co-opted by pathogens that use the tick as a vector and invade the host when the tick bites, such as Borrelia burgdorferi, the causative agent of Lyme borreliosis. Because of the immunity-suppressing role of Salp15, it has been proposed as a candidate for therapeutic applications in disorders of the immune system. The protein is produced as a 135-residue long polypeptide and secreted without its N-terminal signal 1–21 sequence. Detailed structural studies on Salp15 are lacking because of the difficulty in producing large amounts of the folded protein. We report the production of Salp15 and its structural analysis by NMR. The protein is monomeric and contains a flexible N-terminal region followed by a folded domain with mixed α + β secondary structures. Our results are consistent with a three-dimensional structural model derived from AlphaFold, which predicts the formation of three disulfide bridges and a free C-terminal cysteine.     

Hedgehog Signalling Modulates Immune Response and Protects against Experimental Autoimmune Encephalomyelitis

The Hedgehog (Hh) pathway is essential for the embryonic development and homeostatic maintenance of many adult tissues and organs. It has also been associated with some functions of the innate and adaptive immune system. However, its involvement in the immune response has not been well determined. Here we study the role of Hh signalling in the modulation of the immune response by using the Ptch-1-LacZ^+/− mouse model (hereinafter referred to as ptch^+/−), in which the hemizygous inactivation of Patched-1, the Hh receptor gene, causes the constitutive activation of Hh response genes. The in vitro TCR stimulation of spleen and lymph node (LN) T cells showed increased levels of Th2 cytokines (IL-4 and IL-10) in ptch^+/−cells compared to control cells from wild-type (wt) littermates, suggesting that the Th2 phenotype is favoured by Hh pathway activation. In addition, CD4⁺ cells secreted less IL-17, and the establishment of the Th1 phenotype was impaired in ptch^+/− mice. Consistently, in response to an inflammatory challenge by the induction of experimental autoimmune encephalomyelitis (EAE), ptch^+/− mice showed milder clinical scores and more minor spinal cord damage than wt mice. These results demonstrate a role for the Hh/ptch pathway in immune response modulation and highlight the usefulness of the ptch^+/− mouse model for the study of T-cell-mediated diseases and for the search for new therapeutic strategies in inflammatory diseases.     

Synthesis of ω‐amino‐α‐phenylcarbonate alkanes and their polymerization to [n]‐polyurethanes

Aliphatic [n]‐polyurethanes have recently been synthesized from ω‐isocyanato‐α‐alkanols or, more traditionally, by cationic ring‐opening polymerization of cyclourethanes or by the Bu₂Sn(OMe)₂‐promoted polycondensation of ω‐hydroxy‐α‐O‐phenylurethane alkanes. For the latter procedures, the conditions employed do not seem to be suitable for highly functionalized monomers. In contrast, the polymerization of ω‐amino‐α‐phenylcarbonate alkanes is expected to occur under milder conditions. ω‐Amino‐α‐phenylcarbonate alkanes have been synthesized from 6‐aminohexanol (1) and 3‐aminopropanol (6). The procedure involves the N‐Boc protection of the amino group, followed by activation of the alcohol. Removal of the N‐Boc affords the corresponding ω‐amino‐1‐O‐phenyloxycarbonyloxyalkane hydrochlorides. Other oligomeric comonomers between 1 and 6 have been prepared. The polymerization of these precursors takes place in the absence of metal catalysts to afford the corresponding linear and regioregular [n]‐polyurethanes. The procedure described is useful for the preparation of stable ω‐amino‐α‐phenylcarbonate alkane derivatives, which possess varied chain lengths between the terminal functions. These monomers yield [n]‐polyurethanes having various structures starting from just two aminoalkanols. The polyurethanes were obtained in high yields, with reasonable molecular weight and polydispersity values, and they were characterized spectroscopically and thermally. These studies reveal constitutionally uniform structures that are free of carbonate or urea linkages. Copyright © 2010 Society of Chemical Industry     

Analysis of Brazilian SHP policy and its regulation scenario

This article presents the main regulatory changes that occurred in the Brazilian power sector in 2009, along with the impacts these changes caused on the market, especially related to small hydropower (<30 MW). This study addresses regulatory issues based on inventory studies and records of basic projects, changes related to the compensation of the assured energy of SHPs in the Brazilian energy reallocation market, the socio-economic impact resulting from the construction of SHPs, SHPs in alternative resource auctions and finally the general outlook for the growth scenario for SHPs in Brazil according to the ten-year plan (2010–2019). The overall conclusions of this investigation were that the 2008/2009 biennium was a period of great changes in the regulation of small hydropower plants in Brazil, and the SHP market has shown maturity. Additionally, despite SHP being a type of technology that is completely dominated by domestic industry, in recent years, they have experienced policy disincentives caused by changes to rules that inhibit their growth.     

Analysis and mathematical modelling of the behaviour of Escherichia coli in the mascarpone cheese during cold storage

The aim of this work was to study the behaviour of E. coli in mascarpone cheese during storage at the temperatures ranging from 3 to 15 °C, as well as application of predictive microbiology to describe the experimental data. The Baranyi, Gompertz and logistic models were fitted at the stage of primary modelling. Although all applied primary models described the growth of micro‐organisms accurately, the most accurate goodness of fit was obtained for the Gompertz model and the growth rates generated by this model were used for secondary modelling. The polynomial model predicted accurately the influence of temperature on the growth rate of E. coli, reaching the adjusted coefficient of linear regression 0.99. Generated predictive model that describes the growth of E. coli in mascarpone cheese constitutes a valuable tool in assessing the microbiological stability of the food product with similar physicochemical properties.     

Validation of a UV Spectrophotometric Method for Determination of Proteolytic Activity of Enzymatic Detergents

Enzymatic detergents are widely used in health services. These products should be controlled to ensure their activity. In this paper, a UV spectrophotometric method for the determination of proteolytic activity in enzymatic detergents was validated. An artificial substrate (azocasein) was used to quantify the enzyme activity at 340 nm. The results showed that the method was satisfactory in respect to its specificity, linearity, precision, accuracy and robustness. This method fulfills both ICH’s and Brazilian criteria, demonstrating its suitability for routine analysis as well as its potential application for regulatory purposes.     

Impacts of climate changes on crop physiology and food quality

Carbon emissions related to human activities have been significantly contributing to the elevation of atmospheric [CO₂] and temperature. More recently, carbon emissions have greatly accelerated, thus much stronger effects on crops are expected. Here, we revise literature data concerning the physiological effects of CO₂ enrichment and temperature rise on crop species. We discuss the main advantages and limitations of the most used CO₂-enrichment technologies, the Open-Top Chambers (OTCs) and the Free-Air Carbon Enrichment (FACE). Within the conditions expected for the next few years, the physiological responses of crops suggest that they will grow faster, with slight changes in development, such as flowering and fruiting, depending on the species. There is growing evidence suggesting that C₃ crops are likely to produce more harvestable products and that both C₃ and C₄ crops are likely to use less water with rising atmospheric [CO₂] in the absence of stressful conditions. However, the beneficial direct impact of elevated [CO₂] on crop yield can be offset by other effects of climate change, such as elevated temperatures and altered patterns of precipitation. Changes in food quality in a warmer, high-CO₂ world are to be expected, e.g., decreased protein and mineral nutrient concentrations, as well as altered lipid composition. We point out that studies related to changes in crop yield and food quality as a consequence of global climatic changes should be priority areas for further studies, particularly because they will be increasingly associated with food security.     

Oil and fungal biomass dispersion in a stirred tank containing a simulated fermentation broth

The production of γ‐decalactone by the filamentous fungus Trichoderma harzianum involves four phases (oil–water–air–mycelium) and its dispersion is crucial during fermentation. Oil and biomass (when present) dispersion, as a function of the volumetric power drawn (P/V), was characterized, in two; three‐ and four‐phase systems agitated with Rushton turbines. Trichoderma harzianum mycelium was used as the solid phase in the four‐phase system. Two stages of the fermentation were simulated: the beginning (15% oil and 1.4 kgm^?3 of mycelium) and the end (2% oil and 10.6 kg m^?3 of mycelium). In the two‐phase system, the use of exhausted broth achieved higher oil dispersions at low P/V values as compared with distilled water. Aeration decreased the oil dispersion for the high‐oil system, but enhanced oil dispersion for the low‐oil system. Compared with the P/V used in the actual fermentation (0.2 kW m^?3), a high segregation of the system was observed for the high‐oil/low‐biomass system, due to the difficulty of mixing the thick oil–air emulsion present at the top of the tank. The system simulating the end of the fermentation reached almost complete homogeneity of oil and biomass, a phenomenon due to the high biomass/oil ratio and the biomass acting as an oil carrier. © 2001 Society of Chemical Industry     

Fluorescent core-sheath fibers by electrospinning of a phenyleneethynylene/poly(styrene-co-maleimide) blend

Ultrafine fluorescent fibers were prepared by electrospinning of a phenyleneethynylene oligomer mixed in DMF with a poly(styrene-co-maleimide) (PSM). The microscopic characterization by SEM reveals that the fibers are smooth and entangled one to the others forming a non-woven mat with an average diameter of 490 nm. By TEM, a core-sheath type structure is observed which derives from phase segregation between the PSM interacting with the oligomer and the excess of PSM that acts as matrix, as supported by XRD and DSC analysis. The membranes are fluorescent emitting at 420 nm, in the blue region, a high energy light, opening the possibility of their application in optoelectronic devices such as fluorescent sensors. Preliminary assays have been performed for the detection of sodium ions.     

Fuzzy clusterwise linear regression analysis with symmetrical fuzzy output variable

The traditional regression analysis is usually applied to homogeneous observations. However, there are several real situations where the observations are not homogeneous. In these cases, by utilizing the traditional regression, we have a loss of performance in fitting terms. Then, for improving the goodness of fit, it is more suitable to apply the so-called clusterwise regression analysis. The aim of clusterwise linear regression analysis is to embed the techniques of clustering into regression analysis. In this way, the clustering methods are utilized for overcoming the heterogeneity problem in regression analysis. Furthermore, by integrating cluster analysis into the regression framework, the regression parameters (regression analysis) and membership degrees (cluster analysis) can be estimated simultaneously by optimizing one single objective function. In this paper the clusterwise linear regression has been analyzed in a fuzzy framework. In particular, a fuzzy clusterwise linear regression model (FCWLR model) with symmetrical fuzzy output and crisp input variables for performing fuzzy cluster analysis within a fuzzy linear regression framework is suggested. For measuring the goodness of fit of the suggested FCWLR model with fuzzy output, a fitting index is proposed. In order to illustrate the usefulness of FCWLR model in practice, several applications to artificial and real datasets are shown.