Associations between pain intensity, pain sensitivity, demographics, psychological factors, disability, physical activity, pain phenotype and COVID-19 history in low back pain: An observational study.

BACKGROUND AND PURPOSE: Knowledge of the factors affecting pain intensity and pain sensitivity can inform treatment targets and strategies aimed at personalizing the intervention, conceivably increasing its positive impact on patients. Therefore, this study aimed to investigate the association between demographic factors (sex and age), body mass index (BMI), psychological factors (anxiety and depression, kinesiophobia and catastrophizing), self-reported physical activity, pain phenotype (symptoms of central sensitization, and nociceptive or neuropathic pain), history of COVID-19 and pain intensity and sensitivity in patients with chronic non-specific low back pain (LBP). METHODS: This was a cross-sectional secondary analysis with 83 participants with chronic non-specific LBP recruited from the community between August 2021 and April 2022. BMI, pain intensity (Visual Analog Scale), pain sensitivity at the lower back and at a distant point [pressure pain threshold], catastrophizing (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale for Kinesiophobia), anxiety and depression (Hospital Anxiety and Depression Scale), pain phenotype (Central Sensitization Inventory and PainDetect Questionnaire), physical activity (International Physical Activity Questionnaire), and disability (Roland Morris Disability Questionnaire) were assessed. Multiple linear regression analyses with pain intensity and sensitivity as the dependent variables were used. RESULTS: The model for pain intensity explained 34% of its variance (Adjusted R2 = -0.343, p < 0.001), with depression and anxiety (p = 0.008) and disability (p = 0.035) reaching statistical significance. The model for pain sensitivity at the lower back, also explained 34% of its variance (Adjusted R2 = 0.344, p < 0.001) at the lower back with sex, BMI, and kinesiophobia reaching statistical significance (p < 0.05) and 15% of the variance at a distant body site (Adjusted R2 = 0.148, p = 0.018) with sex and BMI reaching statistical significance (p < 0.05). DISCUSSION: This study found that different factors are associated with pain intensity and pain sensitivity in individuals with LBP. Increased pain intensity was associated with higher levels of anxiety and depression and disability and increased pain sensitivity was associated with being a female, higher kinesiophobia, and lower BMI.

Pain intensity and pain sensitivity are not increased by a single session of high-intensity interval aerobic exercise in individuals with chronic low back pain: A randomized and controlled trial.

BACKGROUND: Evidence on the acute impact of high-intensity interval aerobic exercise on pain is scarce. This type of exercise might be perceived as increasing pain intensity and pain sensitivity negatively impacting adherence. More evidence on the acute effects of high-intensity interval aerobic exercise in individuals with low back pain (LBP) is needed. OBJECTIVES: To compare the acute effects of a single session of high-intensity interval aerobic exercise, continuous moderate-intensity aerobic exercise, and no exercise on pain intensity and pain sensitivity in patients with chronic non-specific LBP. DESIGN: Randomized controlled trial with three arms. METHOD: Participants were randomly assigned to one of three groups (i) continuous moderate-intensity aerobic exercise, ii) high-intensity interval aerobic exercise, and iii) no intervention. Measures of pain intensity and pressure pain threshold (PPT) at the lower back and at a distant body site (upper limb) were taken before and after 15 min of exercise. RESULTS: Sixty-nine participants were randomized. A significant main effect of time was found for pain intensity (p = 0.011; η2p = 0.095) and for PPT at the lower back (p < 0.001; η2p = 0.280), but not a time versus group interaction (p > 0.05). For PPT at the upper limb, no main effect of time or interaction was found (p > 0.5). CONCLUSIONS: Fifteen minutes of high-intensity interval aerobic exercise does not increase pain intensity or pain sensitivity compared to both moderate-intensity continuous aerobic exercise and no exercise, suggesting that high-intensity interval aerobic exercise can be used in clinical practice and patients reassured that it is unlikely to increase pain.

Removal of mercury by silica-supported ionic liquids: Efficiency and ecotoxicological assessment.

Anthropogenic impacts have affected the coastal environment and contributed to its contamination. Mercury (Hg) is widespread in nature and has been shown to be toxic in even the smallest amounts, negatively affecting not only the marine ecosystem but also the entire trophic chain due to its biomagnification. Mercury ranks third on the Agency for Toxic Substances and Diseases Registry (ATSDR) priority list and it is therefore imperative to develop more effective methods than those currently available to avoid the persistence of this contaminant in aquatic ecosystems. The present study aimed to evaluate the effectiveness of six different silica-supported ionic liquids (SIL) in removing Hg from contaminated saline water, under realistic conditions ([Hg] = 50 µg/L), and to ecotoxicologically evaluate the safety of the SIL-remedied water, using as test model the marine macroalga Ulva lactuca. The results revealed that SIL [Si][C3C1im][SCN] (250 mg/L) was the most effective in removing Hg from solution, with a efficiency up to 99 % in just 6 h, that enable to obtain < 1 µg/L Hg (European guideline in drinking water). U. lactuca exposed to either the SIL and/or the remedied water showed no significant changes in relative growth rate and chlorophyll a and b levels, compared to the control condition. Biomarker analysis (LPO, GSH, GSSG, SOD, GPx, CAT and GRed) also showed no significant changes in the biochemical performance of U. lactuca. Therefore, it could be assumed that water treatment with SIL or its presence in an aqueous environment does not pose toxicity levels that could inhibit the metabolism or cause cell damage to U. lactuca.

Corrigendum: Ionic-liquid-based approaches to improve biopharmaceuticals downstream processing and formulation.

[This corrects the article DOI: 10.3389/fbioe.2023.1037436.].

Ionic-liquid-based approaches to improve biopharmaceuticals downstream processing and formulation.

The emergence of biopharmaceuticals, including proteins, nucleic acids, peptides, and vaccines, revolutionized the medical field, contributing to significant advances in the prophylaxis and treatment of chronic and life-threatening diseases. However, biopharmaceuticals manufacturing involves a set of complex upstream and downstream processes, which considerably impact their cost. In particular, despite the efforts made in the last decades to improve the existing technologies, downstream processing still accounts for more than 80% of the total biopharmaceutical production cost. On the other hand, the formulation of biological products must ensure they maintain their therapeutic performance and long-term stability, while preserving their physical and chemical structure. Ionic-liquid (IL)-based approaches arose as a promise alternative, showing the potential to be used in downstream processing to provide increased purity and recovery yield, as well as excipients for the development of stable biopharmaceutical formulations. This manuscript reviews the most important progress achieved in both fields. The work developed is critically discussed and complemented with a SWOT analysis.

Granulated biomass fly ash coupled with fenton process for pulp and paper wastewater treatment.

The work describes the combination of granulated biomass fly ash (GBFA) with Fenton process to enhance the removal of adsorbable organic halides (AOX) from pulp bleaching wastewater. At optimal operating conditions, wastewater's chemical and biochemical oxygen demand (COD and BOD5, respectively) and colour were also quantified, and operating cost of treatment assessed. For the first time, raw pulp bleaching wastewater was used to granulate BFA, instead of water, reducing the water footprint of the treatment. Five wastewater treatment setups were studied: (i) conventional Fenton process; (ii) GBFA application; (iii) simultaneous application of GBFA and Fenton process; (iv) sequential treatment by GBFA followed by Fenton process; (v) sequential treatment by Fenton process followed by GBFA. The latter yielded the highest AOX removal (60-70%), whilst COD was also reduced (≈15%) and wastewater biodegradability (BOD5/COD) was enhanced from 0.075 to a maximum of 0.134. Another positive feature of the proposed solution was that GBFA were successfully recovered and reused without regeneration, yielding similar AOX removal compared with fresh GBFA. The operating cost of removing 1 g of AOX from the pulp bleaching wastewater by the optimal treatment setup (60-70% removal of AOX) was 14-26% lower than the operating cost of conducting Fenton process alone (50% removal of AOX).

Valorisation of residual iron dust as Fenton catalyst for pulp and paper wastewater treatment.

In this work, the performance of residual iron dust (RID) from metallurgic industry was assessed as Fenton catalyst for the treatment of real pulp bleaching wastewater. The focus was on the removal of recalcitrant pollutants AOX (adsorbable organic halides), by a novel, cleaner, and cost-effective circular solution based on a waste-derived catalyst. The behaviour of RID as iron source was firstly assessed by performing leaching tests at different RID:wastewater w/v ratios and contact time. Afterwards, RID-catalysed homogeneous and heterogeneous Fenton processes were conducted to maximise AOX removal from the pulp bleaching wastewater. Reusability of RID was assessed by a simple collect-and-reuse methodology, without any modification. Similar AOX removal under less consumption of chemicals was achieved with the novel heterogeneous Fenton process. Reaction in the bulk solution was the main pathway of AOX removal, given that the low surface area and porosity of the material did not allow for a high contribution of surface reaction to the overall performance. Moreover, AOX removal was similar over two consecutive treatment cycles, with Fenton process being responsible for 56.7-62.1% removal of AOX from the wastewater, and the leaching step adding 11.4-13.2%. At the end of treatment, COD either decreased (1st cycle) or remained unchanged (2nd and 3rd cycle). The operating cost of the optimised heterogeneous Fenton was 3-11% lower than under conventional Fenton process. This work presented a novel, circular solution based on a low-cost waste-derived catalyst, advancing the knowledge needed to foster industrial application of such technologies to increase industrial environmental performance and efficiency.

Immobilization and Characterization of L-Asparaginase over Carbon Xerogels.

L-asparaginase (ASNase) is an aminohydrolase currently used in the pharmaceutical and food industries. Enzyme immobilization is an exciting option for both applications, allowing for a more straightforward recovery and increased stability. High surface area and customizable porosity make carbon xerogels (CXs) promising materials for ASNase immobilization. This work describes the influence of contact time, pH, and ASNase concentration on the immobilization yield (IY) and relative recovered activity (RRA) using the Central Composite Design methodology. The most promising results were obtained using CX with an average pore size of 4 nm (CX-4), reaching IY and RRA of 100%. At the optimal conditions (contact time 49 min, pH 6.73, and [ASNase] 0.26 mg·mL-1), the ASNase-CXs biocomposite was characterized and evaluated in terms of kinetic properties and operational, thermal, and pH stabilities. The immobilized ASNase onto CX-4 retained 71% of its original activity after six continuous reaction cycles, showed good thermal stability at 37 °C (RRA of 91% after 90 min), and was able to adapt to both acidic and alkaline environments. Finally, the results indicated a 3.9-fold increase in the immobilized ASNase affinity for the substrate, confirming the potential of CXs as a support for ASNase and as a cost-effective tool for subsequent use in the therapeutic and food sectors.

Supported Ionic Liquids Used as Chromatographic Matrices in Bioseparation-An Overview.

Liquid chromatography plays a central role in biomanufacturing, and, apart from its use as a preparative purification strategy, either in biopharmaceuticals or in fine chemicals industries, it is also very useful as an analytical tool for monitoring, assessing, and characterizing diverse samples. The present review gives an overview of the progress of the chromatographic supports that have been used in the purification of high-value products (e.g., small molecules, organic compounds, proteins, and nucleic acids). Despite the diversity of currently available chromatographic matrices, the interest in innovative biomolecules emphasizes the need for novel, robust, and more efficient supports and ligands with improved selectivity. Accordingly, ionic liquids (ILs) have been investigated as novel ligands in chromatographic matrices. Given herein is an extensive review regarding the different immobilization strategies of ILs in several types of supports, namely in silica, Sepharose, and polymers. In addition to depicting their synthesis, the main application examples of these supports are also presented. The multiple interactions promoted by ILs are critically discussed concerning the improved selectivity towards target molecules. Overall, the versatility of supported ILs is here considered a critical point to their exploitation as alternatives to the more conventional liquid chromatographic matrices used in bioseparation processes.

High Performance of Ionic-Liquid-Based Materials to Remove Insecticides.

Neonicotinoids are systemic insecticides commonly used for pest control in agriculture and veterinary applications. Due to their widespread use, neonicotinoid insecticides (neonics) are found in different environmental compartments, including water, soils, and biota, in which their high toxicity towards non-target organisms is a matter of great concern. Given their widespread use and high toxicity, the development of strategies to remove neonics, while avoiding further environmental contamination is of high priority. In this work, ionic-liquid-based materials, comprising silica modified with tetraalkylammonium cations and the chloride anion, were explored as alternative adsorbent materials to remove four neonics insecticides, namely imidacloprid, acetamiprid, thiacloprid, and thiamethoxam, from aqueous media. These materials or supported ionic liquids (SILs) were first synthesized and chemically characterized and further applied in adsorption studies. It was found that the equilibrium concentration of the adsorbate in the solid phase decreases with the decrease in the SIL cation alkyl chain length, reinforcing the relevance of hydrophobic interactions between ionic liquids (ILs) and insecticides. The best-identified SIL for the adsorption of the studied insecticides corresponds to silica modified with propyltrioctylammonium chloride ([Si][N3888]Cl). The saturation of SILs was reached in 5 min or less, showing their fast adsorption rate towards all insecticides, in contrast with activated carbon (benchmark) that requires 40 to 60 min. The best fitting of the experimental kinetic data was achieved with the Pseudo Second-Order model, meaning that the adsorption process is controlled at the solid-liquid interface. On the other hand, the best fitting of the experimental isotherm data is given by the Freundlich isotherm model, revealing that multiple layers of insecticides onto the SIL surface may occur. The continuous removal efficiency of the best SIL ([Si][N3888]Cl) by solid-phase extraction was finally appraised, with the maximum adsorption capacity decreasing in the following sequence: imidacloprid > thiacloprid > thiamethoxam > acetamiprid. Based on real reported values, under ideal conditions, 1 g of [Si][N3888]Cl is able to treat at least 106 m3 of wastewater and water from wetland contaminated with the studied neonics. In summary, the enhanced adsorption capacity of SILs for a broad diversity of neonics was demonstrated, reinforcing the usefulness of these materials for their removal from aqueous matrices and thus contributing to preventing their introduction into the ecosystems and reducing their detrimental effects in the environment and human health.

Enhanced Enzyme Reuse through the Bioconjugation of L-Asparaginase and Silica-Based Supported Ionic Liquid-like Phase Materials.

L-asparaginase (ASNase) is an amidohydrolase that can be used as a biopharmaceutical, as an agent for acrylamide reduction, and as an active molecule for L-asparagine detection. However, its free form displays some limitations, such as the enzyme's single use and low stability. Hence, immobilization is one of the most effective tools for enzyme recovery and reuse. Silica is a promising material due to its low-cost, biological compatibility, and tunable physicochemical characteristics if properly functionalized. Ionic liquids (ILs) are designer compounds that allow the tailoring of their physicochemical properties for a given task. If properly designed, bioconjugates combine the features of the selected ILs with those of the support used, enabling the simple recovery and reuse of the enzyme. In this work, silica-based supported ionic liquid-like phase (SSILLP) materials with quaternary ammoniums and chloride as the counterion were studied as novel supports for ASNase immobilization since it has been reported that ammonium ILs have beneficial effects on enzyme stability. SSILLP materials were characterized by elemental analysis and zeta potential. The immobilization process was studied and the pH effect, enzyme/support ratio, and contact time were optimized regarding the ASNase enzymatic activity. ASNase-SSILLP bioconjugates were characterized by ATR-FTIR. The bioconjugates displayed promising potential since [Si][N3444]Cl, [Si][N3666]Cl, and [Si][N3888]Cl recovered more than 92% of the initial ASNase activity under the optimized immobilization conditions (pH 8, 6 × 10-3 mg of ASNase per mg of SSILLP material, and 60 min). The ASNase-SSILLP bioconjugates showed more enhanced enzyme reuse than reported for other materials and immobilization methods, allowing five cycles of reaction while keeping more than 75% of the initial immobilized ASNase activity. According to molecular docking studies, the main interactions established between ASNase and SSILLP materials correspond to hydrophobic interactions. Overall, it is here demonstrated that SSILLP materials are efficient supports for ASNase, paving the way for their use in the pharmaceutical and food industries.

Towards the Use of Adsorption Methods for the Removal of Purines from Beer.

Beer corresponds to a fermented alcoholic beverage composed of several components, including purine compounds. These molecules, when ingested by humans, can be catabolized into uric acid, contributing to uric acid's level increase in serum, which may lead to hyperuricemia and gout. To assure a proper management of this disease, physicians recommend restrictive dietary measures, particularly by avoiding the consumption of beer. Therefore, it is of relevance to develop efficient methods to remove purine compounds from alcoholic beverages such as beer. In this review, we provide an introduction on fermented alcoholic beverages, with emphasis on beer, as well as its purine compounds and their role in uric acid metabolism in the human body in relation to hyperuricemia and gout development. The several reported enzymatic, biological and adsorption methods envisaging purine compounds' removal are then reviewed. Some enzymatic and biological methods present drawbacks, which can be overcome by adsorption methods. Within adsorption methods, adsorbent materials, such as activated carbon or charcoal, have been reported and applied to beer or wort samples, showing an excellent capacity for adsorbing and removing purine compounds. Although the main topic of this review is on the removal of purine compounds from beer, other studies involving other matrices rather than beer or wort that are rich in purines are included, since they provide relevant clues on designing efficient removal processes. By ensuring the selective removal of purine compounds from this beverage, beer can be taken by hyperuricemic and gouty patients, avoiding restrictive dietary measures, while decreasing the related healthcare economic burden.

Superior operational stability of immobilized L-asparaginase over surface-modified carbon nanotubes.

L-asparaginase (ASNase, EC 3.5.1.1) is an enzyme that catalyzes the L-asparagine hydrolysis into L-aspartic acid and ammonia, being mainly applied in pharmaceutical and food industries. However, some disadvantages are associated with its free form, such as the ASNase short half-life, which may be overcome by enzyme immobilization. In this work, the immobilization of ASNase by adsorption over pristine and modified multi-walled carbon nanotubes (MWCNTs) was investigated, the latter corresponding to functionalized MWCNTs through a hydrothermal oxidation treatment. Different operating conditions, including pH, contact time and ASNase/MWCNT mass ratio, as well as the operational stability of the immobilized ASNase, were evaluated. For comparison purposes, data regarding the ASNase immobilization with pristine MWCNT was detailed. The characterization of the ASNase-MWCNT bioconjugate was addressed using different techniques, namely Transmission Electron Microscopy (TEM), Thermogravimetric Analysis (TGA) and Raman spectroscopy. Functionalized MWCNTs showed promising results, with an immobilization yield and a relative recovered activity of commercial ASNase above 95% under the optimized adsorption conditions (pH 8, 60 min of contact and 1.5 × 10-3 g mL-1 of ASNase). The ASNase-MWCNT bioconjugate also showed improved enzyme operational stability (6 consecutive reaction cycles without activity loss), paving the way for its use in industrial processes.

Advances Achieved by Ionic-Liquid-Based Materials as Alternative Supports and Purification Platforms for Proteins and Enzymes.

Ionic liquids (ILs) have been applied in several fields in which enzymes and proteins play a noteworthy role, for instance in biorefinery, biotechnology, and pharmaceutical sciences, among others. Despite their use as solvents and co-solvents, their combination with materials for protein- and enzyme-based applications has raised significant attention in the past few years. Among them, significant advances were brought by supported ionic liquids (SILs), in which ILs are introduced to modify the surface and properties of materials, e.g., as ligands when covalently bond or when physiosorbed. SILs have been mainly investigated as alternative supports for enzymes in biocatalysis and as new supports in preparative liquid chromatography for the purification of high-value proteins and enzymes. In this manuscript, we provide an overview on the most relevant advances by using SILs as supports for enzymes and as purification platforms for a variety of proteins and enzymes. The interaction mechanisms occurring between proteins and SILs/ILs are highlighted, allowing the design of efficient processes involving SILs. The work developed is discussed in light of the respective development phase and innovation level of the applied technologies. Advantages and disadvantages are identified, as well as the missing links to pave their use in relevant applications.

Efficient Isolation of Bacterial RNAs Using Silica-Based Materials Modified with Ionic Liquids.

High quality nucleic acids (with high integrity, purity, and biological activity) have become indispensable products of modern society, both in molecular diagnosis and to be used as biopharmaceuticals. As the current methods available for the extraction and purification of nucleic acids are laborious, time-consuming, and usually rely on the use of hazardous chemicals, there is an unmet need towards the development of more sustainable and cost-effective technologies for nucleic acids purification. Accordingly, this study addresses the preparation and evaluation of silica-based materials chemically modified with chloride-based ionic liquids (supported ionic liquids, SILs) as potential materials to effectively isolate RNAs. The investigated chloride-based SILs comprise the following cations: 1-methyl-3-propylimidazolium, triethylpropylammonium, dimethylbutylpropylammonium, and trioctylpropylammonium. All SILs were synthesized by us and characterized by solid-state 13C Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), elemental analysis, and zeta potential measurements, confirming the successful covalent attachment of each IL cation with no relevant changes in the morphology of materials. Their innovative application as chromatographic supports for the isolation of recombinant RNA was then evaluated. Adsorption kinetics of transfer RNA (tRNA) on the modified silica-based materials were investigated at 25 °C. Irrespective to the immobilized IL, the adsorption experimental data are better described by a pseudo first-order model, and maximum tRNA binding capacities of circa 16 µmol of tRNA/g of material were achieved with silica modified with 1-methyl-3-propylimidazolium chloride and dimethylbutylpropylammonium chloride. Furthermore, the multimodal character displayed by SILs was explored towards the purification of tRNA from Escherichia coli lysates, which in addition to tRNA contain ribosomal RNA and genomic DNA. The best performance on the tRNA isolation was achieved with SILs comprising 1-methyl-3-propylimidazolium chloride and dimethylbutylpropylammonium chloride. Overall, the IL modified silica-based materials represent a more efficient, sustainable, and cost-effective technology for the purification of bacterial RNAs, paving the way for their use in the purification of distinct biomolecules or nucleic acids from other sources.

Interferon-Based Biopharmaceuticals: Overview on the Production, Purification, and Formulation.

The advent of biopharmaceuticals in modern medicine brought enormous benefits to the treatment of numerous human diseases and improved the well-being of many people worldwide. First introduced in the market in the early 1980s, the number of approved biopharmaceutical products has been steadily increasing, with therapeutic proteins, antibodies, and their derivatives accounting for most of the generated revenues. The success of pharmaceutical biotechnology is closely linked with remarkable developments in DNA recombinant technology, which has enabled the production of proteins with high specificity. Among promising biopharmaceuticals are interferons, first described by Isaacs and Lindenmann in 1957 and approved for clinical use in humans nearly thirty years later. Interferons are secreted autocrine and paracrine proteins, which by regulating several biochemical pathways have a spectrum of clinical effectiveness against viral infections, malignant diseases, and multiple sclerosis. Given their relevance and sustained market share, this review provides an overview on the evolution of interferon manufacture, comprising their production, purification, and formulation stages. Remarkable developments achieved in the last decades are herein discussed in three main sections: (i) an upstream stage, including genetically engineered genes, vectors, and hosts, and optimization of culture conditions (culture media, induction temperature, type and concentration of inducer, induction regimens, and scale); (ii) a downstream stage, focusing on single- and multiple-step chromatography, and emerging alternatives (e.g., aqueous two-phase systems); and (iii) formulation and delivery, providing an overview of improved bioactivities and extended half-lives and targeted delivery to the site of action. This review ends with an outlook and foreseeable prospects for underdeveloped aspects of biopharma research involving human interferons.

Protein-olive oil-in-water nanoemulsions as encapsulation materials for curcumin acting as anticancer agent towards MDA-MB-231 cells.

The sustainable cellular delivery of the pleiotropic drug curcumin encounters drawbacks related to its fast autoxidation at the physiological pH, cytotoxicity of delivery vehicles and poor cellular uptake. A biomaterial compatible with curcumin and with the appropriate structure to allow the correct curcumin encapsulation considering its poor solubility in water, while maintaining its stability for a safe release was developed. In this work, the biomaterial developed started by the preparation of an oil-in-water nanoemulsion using with a cytocompatible copolymer (Pluronic F 127) coated with a positively charged protein (gelatin), designed as G-Cur-NE, to mitigate the cytotoxicity issue of curcumin. These G-Cur-NE showed excellent capacity to stabilize curcumin, to increase its bio-accessibility, while allowing to arrest its autoxidation during its successful application as an anticancer agent proved by the disintegration of MDA-MB-231 breast cancer cells as a proof of concept.

Adapted Chester Step Test Can Have Maximal Response Characteristics for the Assessment of Exercise Capacity in Young Women.

Chester step test (CST) estimates the exercise capacity through a submaximal response, which can limit its application in the prescription of exercise. This study aimed to assess whether an adaptation of the CST (with a progressive profile) can have maximal response characteristics in young women and compare it to the incremental shuttle walk test (ISWT). Another aim was to determine its within-day test-retest reliability. A cross-sectional study was conducted with 25 women (20.3 ± 1.5 years) who performed the field tests twice on two different days (48 h apart). The maximal effort attainment was assessed by the heart rate (HR), perception of exertion (Borg scale), and blood lactate concentration. For the performance variables, Pearson's correlation and intraclass correlation coefficient (ICC2,1) were used. In the best test, mean values of maximal response were observed in the adapted CST (94.0 ± 6.5% of age-predicted HRmax, 11.3 ± 4.5 mmol/dl of blood lactate, and 18.4 ± 1.5 of Borg rating). The correlations between the adapted CST and the ISWT were weak to moderate (0.38 ≤ r ≤ 0.55; p < 0.05). Fair to good reliability was found for the adapted CST (ICC2,1 = 0.48-0.61). The adapted CST showed mean values of maximal response, weak to moderate association with the ISWT, and low within-day test-retest reliability in young women.

Development and characterization of a novel l-asparaginase/MWCNT nanobioconjugate.

The enzyme l-asparaginase (ASNase) presents effective antineoplastic properties used for acute lymphoblastic leukemia treatment besides their potential use in the food sector to decrease the acrylamide formation. Considering their applications, the improvement of this enzyme's properties by efficient immobilization techniques is in high demand. Carbon nanotubes are promising enzyme immobilization supports, since these materials have increased surface area and effective capacity for enzyme loading. Accordingly, in this study, multi-walled carbon nanotubes (MWCNTs) were explored as novel supports for ASNase immobilization by a simple adsorption method. The effect of pH and contact time of immobilization, as well as the ASNase to nanoparticles mass ratio, were optimized according to the enzyme immobilization yield and relative recovered activity. The enzyme-MWCNTs bioconjugation was confirmed by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), Raman and transmission electron microscopy (TEM) studies. MWCNTs have a high ASNase loading capacity, with a maximum immobilization yield of 90%. The adsorbed ASNase retains 90% of the initial enzyme activity at the optimized conditions (pH 8.0, 60 min, and 1.5 × 10-3 g mL-1 of ASNase). According to these results, ASNase immobilized onto MWCNTs can find improved applications in several areas, namely biosensors, medicine and food industry.

Structural insights into the effect of cholinium-based ionic liquids on the critical micellization temperature of aqueous triblock copolymers.

Symmetrical poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-PPG-PEG) triblock copolymer with 82.5% PEG as the hydrophilic end blocks, and PPG as the hydrophobic middle block, was chosen to study the effect of ionic liquids (ILs) on the critical micellization temperature (CMT) of block copolymers in aqueous solution. In the present work, cholinium-based ILs were chosen to explore the effect of the anions on the copolymer CMT using fluorescence spectroscopy, dynamic light scattering (DLS), viscosity (η), FT-IR spectroscopy, nuclear magnetic resonance (NMR), and direct visualization of the various self-assembled nanostructures by scanning electron microscopy (SEM). The result suggests that ILs have the ability to decrease the CMT of the aqueous copolymer solution which is dependent on the nature of the anions of the ILs. The present study reveals that the hydrophobic part PPG of the copolymer has more influence on this behavior than the PEG hydrophilic part.