Small Molecules Present in the Cerebrospinal Fluid Metabolome Influence Superoxide Dismutase 1 Aggregation

Superoxide dismutase 1 (SOD1) aggregation is one of the pathological markers of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. The underlying molecular grounds of SOD1 pathologic aggregation remains obscure as mutations alone are not exclusively the cause for the formation of protein inclusions. Thus, other components in the cell environment likely play a key role in triggering SOD1 toxic aggregation in ALS. Recently, it was found that ALS patients present a specific altered metabolomic profile in the cerebrospinal fluid (CSF) where SOD1 is also present and potentially interacts with metabolites. Here we have investigated how some of these small molecules affect apoSOD1 structure and aggregation propensity. Our results show that as co-solvents, the tested small molecules do not affect apoSOD1 thermal stability but do influence its tertiary interactions and dynamics, as evidenced by combined biophysical analysis and proteolytic susceptibility. Moreover, these compounds influence apoSOD1 aggregation, decreasing nucleation time and promoting the formation of larger and less soluble aggregates, and in some cases polymeric assemblies apparently composed by spherical species resembling the soluble native protein. We conclude that some components of the ALS metabolome that shape the chemical environment in the CSF may influence apoSOD1 conformers and aggregation.     

Recovery of carbon dioxide from sugarcane fermentation broth in the ethanol industry

Ethanol is one alternative to the use of petroleum-based fuels. It is produced on a large scale in Brazil from sugarcane to the magnitude of billions of liters per year. During the ethanol production step, a considerable amount of byproducts is obtained and treated as waste. Carbon dioxide is one of these byproducts and a substance of interest especially for food industries. Because the production of 1000 kg of ethanol generates approximately 950 kg of CO₂, this work intends to analyze a cryogenic distillation process for the production of CO₂ by means of computational simulations. The results obtained were in agreement with real operational conditions, achieving CO₂ concentrations up to 100% (v/v). With an initial CO₂ concentration of 95% (v/v), 7 separation stages were obtained, achieving the limit of 5 stages for higher CO₂ concentrations in the raw gas. The effect of initial CO₂ concentrations on the final product and the concentration profiles along the column are also presented. In order to optimize the process, it was observed that, for a maximum feed flow of 3333 kg/h (CO₂ concentration of 99%), the plant was able to obtain 10.48 kgCO₂/kW, recovering about 2828 kgCO₂/h at a final product concentration of 99.90% (v/v) at ?25 °C.     

Treatment of Chronic Kidney Disease with Extracellular Vesicles from Mesenchymal Stem Cells and CD133+ Expanded Cells: A Comparative Preclinical Analysis

Chronic kidney disease (CKD) is characterized by structural abnormalities and the progressive loss of kidney function. Extracellular vesicles (EVs) from human umbilical cord tissue (hUCT)-derived mesenchymal stem cells (MSCs) and expanded human umbilical cord blood (hUCB)-derived CD133⁺ cells (eCD133⁺) maintain the characteristics of the parent cells, providing a new form of cell-free treatment. We evaluated the effects of EVs from hUCT-derived MSCs and hUCB-derived CD133⁺ cells on rats with CDK induced by an adenine-enriched diet. EVs were isolated by ultracentrifugation and characterized by nanoparticle tracking analysis (NTA) and electron microscopy. The animals were randomized and divided into the MSC-EV group, eEPC-EV group and control group. Infusions occurred on the seventh and 14th days after CKD induction. Evaluations of kidney function were carried out by biochemical and histological analyses. Intense labeling of the α-SMA protein was observed when comparing the control with MSC-EVs. In both groups treated with EVs, a significant increase in serum albumin was observed, and the increase in cystatin C was inhibited. The results indicated improvements in renal function in CKD, demonstrating the therapeutic potential of EVs derived from MSCs and eCD133⁺ cells and suggesting the possibility that in the future, more than one type of EV will be used concurrently.     

Characterization of Crude and Partially Purified Lipase from Geotrichum candidum Obtained with Different Nitrogen Sources

Lipases from Geotrichum candidum were produced in two different medium: A = 12 % (w/v) clarified corn steep liquor (CCSL) + 0.6 % (w/v) soybean oil (SO) and B = 3.5 % (w/v) yeast hydrolysate (YH) + 0.7 % (w/v) SO. Lipases were partially purified from both media by hydrophobic interaction chromatography using 3.0 mol L^?1 of NaCl as mobile phase, and they were characterized in the crude and partially purified forms. The recovery of lipase activity from CCSL and YH via HIC were 96 and 94.3 %, and the purification factors were 44.3 and 86.7‐fold, respectively. All evaluated lipases had similar optimum pH (7.0–7.7), but, for the CCSL crude lipase, optimum temperature (47 °C) was 10 °C higher than others lipases evaluated. CCSL crude lipase possessed a higher thermo stability than YH crude lipase, e.g., at 37 °C (pH 7.0) the half‐life of CCSL crude lipase was 19.25 h and at pH 8.0 (30 °C) the half‐life was 48 h, which are five and ten times higher than with YH crude lipase, respectively. On the other hand, the YH crude lipase possessed a higher catalytic constant (k_cat = 2.3 min^?1) but with almost the same catalytic efficiency (K_m/k_cat = 32.12 mg mL min^?1) in relation to CCSL crude lipase. The lipases differ in biocatalytic properties between substrates, suggesting that the two lipases can be employed for different applications.     

Optimization of osmotic dehydration of yacon slices

Osmotic dehydration assisted by ultrasound (ODAU) at low temperatures reduces water activity (a_w) and maintains nutrients. The influence of solution concentration (SC; 20 to 60° Brix, xylitol and sorbitol) and ultrasound application time (t_us, 0 to 40 min) in ODAU of yacon was studied with the aid of a response surface method. The optimum condition with respect to mass transfer parameters, a_w, and fructan retention was SC of 60° Brix for both solutions and t_us of 2.67 min for xylitol samples and 0 min for sorbitol samples. The application of ultrasound improved dehydration but resulted in depolymerization of fructans.     

Development of New Sulphonyl Resin from Modification of Commercial Resin

Summary This article deals with the handy synthesis of sulfonyl resins, which were produced by the treatment of a commercial sulfonic resin (Lewatit VPOC1812^® based at divinylbenzene (DVB) and styrene (STY). The preliminary chemical modification was based on the reaction of the Lewatit VPOC1812^® with thionyl chloride aiming to produce the sulfonyl chloride groups. The best conditions to obtain the sulfonyl chloride groups were: SOCl₂/SO₃H (molar ratio) =13 at 79 °C during 72 h. The resin chlorinated was afterward treated with urea, thiourea or guanidine. The functionalized resins with urea, thiourea or guanidine were produced with 56, 68 and 93% yield, respectively. The commercial and modified resins were characterized by apparent density, swelling degree, elemental analysis (CHNS), FTIR, optical microscopy (OM) and scanning electron microscopy (SEM).     

Analysis of form threads using fluteless taps in cast magnesium alloy (AM60)

Threads are used in the most assemblies of industrial products. Commonly, mechanical components need to have threaded parts allowing fast and accurate assemblies and disassemblies. Internal tapping is one of the most demanded machining operations, and threads obtained by forming have been a good alternative. This work investigates the effect of the factors the hole diameter, the forming speed and types of tool on the responses: torque, hardness, fill rate, and thrust force of the form tapping process. The experiments were carried out with three diameters, three forming speeds, and two coatings. The material used was the AM60 alloy due to its high ductility and wide application as head engine. The results revealed torque is more affected by the hole diameter than thrust force, and little hardening occurred using high forming speed with a small diameter. The fill rate of the thread profile was not significantly affected by the intermediate and large diameters. Finally, it can be stated that the recommended hole diameter provided by the tool's supplier can be modified to achieve more accurate thread profiles.     

Effect of Hydrogen Treatment on the Catalytic Activity of Iron Oxide Based Materials Dispersed Over Activated Carbon: Investigations Toward Hydrogen Peroxide Decomposition

The effect of hydrogen treatment (400 °C/1 h) on the catalytic properties toward H₂O₂ decomposition of iron oxide based materials dispersed over activated carbon were investigated. Two different supports were evaluated: a commercial activated carbon (ACM) and an activated carbon produced from spent coffee grounds (ACR). The catalysts were characterized using XRD, SEM, N₂-sorption, XPS and TPR analysis. The main results suggest the formation of composites with high surface area (>800 m² g^?1) and the hydrogen treatment resulted in a great increase in the catalytic activity, probably as a function of the reduced iron species (Fe²⁺ and Fe⁰) formed with the treatment. Moreover, the catalyst prepared with ACR showed to be more active than that prepared from ACM.     

Biodegradable composites based on starch/EVOH/glycerol blends and coconut fibers

Unripe coconut fibers were used as fillers in a biodegradable polymer matrix of starch/ethylene vinyl alcohol (EVOH)/glycerol. The effects of fiber content on the mechanical, thermal, and structural properties were evaluated. The addition of coconut fiber into starch/EVOH/glycerol blends reduced the ductile behavior of the matrix by making the composites more brittle. At low fiber content, blends were more flexible, with higher tensile strength than at higher fiber levels. The temperature at the maximum degradation rate slightly shifted to lower values as fiber content increased. Comparing blends with and without fibers, there was no drastic change in melt temperature of the matrix with increase of fiber content, indicating that fibers did not lead to significant changes in crystalline structure. The micrographs of the tensile fractured specimens showed a large number of holes resulting from fiber pull‐out from the matrix, indicating poor adhesion between fiber and matrix. Although starch alone degraded readily, starch/EVOH/glycerol blends exhibited much slower degradation in compost. Composites produced 24.4–28.8% less CO₂ compared with starch in a closed‐circuit respirometer. Addition of increasing amount of fiber in starch/EVOH/glycerol composite had no impact on its biodegradation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009