Search Results (13)

The current economic growth and increasing needs of society have led to developing processes that harm our environment and have severe long-term consequences. For this reason, different attempts have been made to mitigate these effects by substituting conventional toxic materials with environmentally friendly ones. Industry sectors related to energy storage, printed electronics, and wearable technology are moving towards applying sustainable strategies. Renewable biopolymers such as cellulose and its derivatives, as well as carbon-based alternatives, which include carbon nanotubes (CNTs), single-wall carbon nanotubes (SWCNTs), graphite, graphene, and carbon black (CB), are leading the advances in this field. The present research aimed to develop conductive cellulose paper using environmentally friendly components compatible with the paper recycling process. Coating formulations based on carbon black were proposed using three different types of binders: polytetrafluoroethylene (PTFE), latex (styrene butadiene), and sodium carboxymethyl cellulose (CMC). The formulation, composition, and preparation were studied, and they were related to the coating’s electrical resistance and integrity. This last parameter was determined through a new method described in this research, implementing a mechanical/optical technique to measure the coating’s durability. The formulation with the best performance in terms of electrical resistance (0.29 kΩ), integrity, and non-toxicity was obtained using sodium carboxymethyl cellulose (CMC) as a binder and dispersant. Full article

In amnestic mild cognitive impairment (aMCI), neuroinflammation evolves during disease progression, affecting microglial function and potentially accelerating the pathological process. Currently, no effective treatment exists, leading to explorations of various symptomatic approaches, though few target the underlying physiological mechanisms. Modulating inflammatory processes may be critical in slowing disease progression. Cognitive stimulation (CS) and transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (l-DLPFC) show promise, but the results are heterogeneous. Thus, a randomized, double-blind, placebo-controlled clinical trial is currently underway. The first-stage results were examined after three weeks of intervention in two groups: active tDCS combined with CS and sham tDCS combined with CS. Twenty-two participants underwent two assessments: T0 (baseline) and T1 (after 15 sessions of tDCS, active or sham, and 9 sessions of CS). The results demonstrated that CS improved cognition, increased brain-derived neurotrophic factor (BDNF) levels, and reduced peripheral proinflammatory cytokine levels (interleukin IL-6 and chemokine CX3CL1) in serum. This decrease in IL-6 may promote microglial proliferation and survival as a modulatory effect response, while the increase in BDNF might suggest a regulatory mechanism in microglia–neuron interaction responses. However, tDCS did not enhance the cognitive or modulatory effects of CS, suggesting that longer interventions might be required to achieve substantial benefits. Full article

Climate change, principally driven by human activities, has led to an increase in global temperature, which is predicted to continue rising in the coming years. This temperature increase is even more pronounced in urban areas due to the heat island effect. This phenomenon is highly influenced by the presence of paved streets made with bituminous mixtures, which are characterised by their high solar radiation absorption capacity. Bituminous mixtures retain and re-emit a large amount of heat that intensifies the urban heat island effect. The novelty of this work is to measure retroreflective properties of bituminous mixtures that present a highly textured surface. In this context, the aim of this study is to evaluate the retroreflectance of different bituminous mixtures for use as pavement surfaces, focusing on the influence of colour and different types of aggregates. For this, total and directional reflectance measurements were conducted to determine the retroreflectance of these mixtures, with the purpose of mitigating the heat island effect in urban environments without affecting users through reflected solar radiation. The results show the retroreflective capacity of the designed mixtures within the visible spectrum, especially those manufactured with light-coloured aggregates and synthetic binders pigmented with titanium dioxide. Thus, the retroreflectance of the lighter mixtures range from 37.9% at a 0° entrance angle to 68.9% at 60°, while the black mixtures exhibit values between 5.1% and 8.4%. Full article

Biological properties of Sonoran propolis (SP) are influenced by harvest time. Caborca propolis showed cellular protective capacity against reactive oxygen species, which might be implicated in anti-inflammatory effects. However, the anti-inflammatory activity of SP has not been investigated so far. This study investigated the anti-inflammatory activity of previously characterized seasonal SP extracts (SPE) and some of their main constituents (SPC). The anti-inflammatory activity of SPE and SPC was evaluated by measuring nitric oxide (NO) production, protein denaturation inhibition, heat-induced hemolysis inhibition, and hypotonicity-induced hemolysis inhibition. SPE from spring, autumn, and winter showed a higher cytotoxic effect on RAW 264.7 cells (IC₅₀: 26.6 to 30.2 µg/mL) compared with summer extract (IC₅₀: 49.4 µg/mL). SPE from spring reduced the NO secretion to basal levels at the lowest concentration tested (5 µg/mL). SPE inhibited the protein denaturation by 79% to 100%, and autumn showed the highest inhibitory activity. SPE stabilized erythrocyte membrane against heat-induced and hypotonicity-induced hemolysis in a concentration-dependent manner. Results indicate that the flavonoids chrysin, galangin, and pinocembrin could contribute to the anti-inflammatory activity of SPE and that the harvest time influences such a property. This study presents evidence of SPE pharmacological potential and some of their constituents. Full article

Tocilizumab is a first-line biologic disease-modifying anti-rheumatic drug (bDMARD) that inhibits the interleukin-6 (IL-6) pathway by antagonizing the IL-6 receptor (IL-6R). Tocilizumab is widely used to treat rheumatoid arthritis (RA), a prevalent autoimmune disease that can cause irreversible joint damage and disability. Although many bDMARDs have been developed for RA, there is a lack of validated biomarkers which could guide personalized medicine strategies. To evaluate whether single-nucleotide polymorphisms (SNPs) in the IL6R gene could predict tocilizumab toxicity in patients with RA, we conducted a retrospective cohort study of 88 patients treated with tocilizumab. Six SNPs previously described in the IL6R gene were genotyped (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625). Using parametric tests, we studied the association between the SNPs and hepatotoxicity, infection, hypersensitivity, gastrointestinal, hematological, and dyslipidemia adverse events (AEs). We found associations between dyslipidemia and rs4845625 and between hematological AEs and rs11265618 and rs4329505. No further associations were found for the remaining SNPs and other AEs. Our findings support the potential clinical value of SNPs in the IL6R gene as predictive biomarkers for toxicity to tocilizumab in patients with RA. Full article

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by chronic arthritis that may lead to irreversible joint damage and significant disability. Patients with RA are commonly treated with Tocilizumab (TCZ), an IL-6 receptor (IL-6R) antagonist, but many patients refractorily respond to this therapy. Identifying genetic biomarkers as predictors of TCZ response could be a key to providing a personalized medicine strategy. We aimed to evaluate whether functional single nucleotide polymorphisms (SNPs) in the IL6R gene could predict TCZ response in patients with RA. We retrospectively included 88 RA patients treated with TCZ. Six SNPs previously described in the IL6R gene (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625) were genotyped in DNA samples from these patients. Using parametric tests, we evaluated the association between these polymorphisms and clinicopathological features. Responses to treatments were assessed at six months using three variables: a quantitative improvement in Disease activity score including 28 joints (DAS28), a satisfactory European League Against Rheumatism (EULAR) response, and low disease activity (LDA) achievement. The three response variables studied were associated with genetic variant rs4845625, and no association was found with the other five SNPs. Our findings support the potential clinical value of SNPs in the IL6R gene as predictive biomarkers for TCZ response. Full article

Tick-borne bacterial pathogens (TBBPs) show a worldwide distribution and represent a great impact on public health. The brown dog tick (Rhipicephalus sanguineus) is a vector of several pathogens that affect dogs and sometimes humans as well. In addition, TBBPs represent a diagnostic challenge and imply financial resources and medical treatment for long periods of time. In the present study, R. sanguineus s. l. was identified as the main tick species naturally parasitizing dogs that inhabit. Juárez City, Chihuahua, in the Paso del Norte region, Mexico–US Border, representing 99.8% of the cases. Additionally, an end-point PCR was performed to search for whether pathogens in R. sanguineus s. l. can transmit in DNA extracted from ticks and dog blood samples. This is the first molecular detection of Rickettsia rickettsi infecting domestic dogs in Mexico; however, other pathogens were also identified, such as Ehrlichia canis and Anaplasma platys in both ticks and dog blood samples, while Anaplasma phagocytophilum was identified only in dog blood samples. Moreover, co-detection in tick pools and co-infection in the analyzed dog blood samples could be found. Similarly, this research showed that dogs were found mostly parasitized by adult female ticks, increasing the possibility of transmission of E. canis. Full article

This study aims to determine the effect of the weight of bitches on liveborn and stillbirth puppies from eutocic births, and physiological blood alterations during the first minute postpartum. A total of 52 female dogs were evaluated and distributed in four categories: C1 (4.0–8.0 kg, n = 19), C2 (8.1–16.0 kg, n = 16), C3 (16.1–32.0 kg, n = 11), and C4 (32.1–35.8 kg, n = 6). The dams produced 225 liveborn puppies and 47 were classified as stillbirth type II. Blood samples were taken from the umbilical vein to evaluate the concentration of gases, glucose, lactate, calcium, hematocrit levels, and blood pH. The liveborn puppies in C2, C3, and C4 had more evident physiological alterations (hypercapnia, acidosis) than those in C1 (p < 0.05). These signs indicate a process of transitory asphyxiation. The stillborn pups in all four categories had higher weights than their liveborn littermates. C3 and C4 had the highest mean weights (419.86 and 433.79 g, respectively) and mortality rates (C3 = 20.58%, C4 = 24.58%). Results suggest that if the weight of the bitch is >16.1 kg in eutocic births, there is a higher risk of intrapartum physiological alterations and death. The results of this study allowed us to identify that the weight of dams before birth determines the weight of the puppies at birth. Full article

Nano-delivery systems represent one of the most studied fields, thanks to the associated improvement in the treatment of human diseases. The functionality of nanostructures is a crucial point, which the effectiveness of nanodrugs depends on. A hybrid approach strategy using synthetic nanoparticles (NPs) and erythrocytes offers an optimal blend of natural and synthetic materials. This, in turn, allows medical practitioners to exploit the combined advantages of erythrocytes and NPs. Erythrocyte-based drug delivery systems have been investigated for their biocompatibility, as well as the long circulation time allowed by specific surface receptors that inhibit immune clearance. In this review, we will discuss several methods—whole erythrocytes as drug carriers, red blood cell membrane-camouflaged nanoparticles and nano-erythrosomes (NERs)—while paying attention to their application and specific preparation methods. The ability to target cells makes erythrocytes excellent drug delivery systems. They can carry a wide range of therapeutic molecules while also acting as bioreactors; thus, they have many applications in therapy and in the diagnosis of many diseases. Full article

Although there is convincing scientific research for the role of Indigenous fire practices in sustainable land management, Indigenous peoples’ involvement in policy-making is limited. This paper presents findings from a fire management workshop where experiences and perspectives were shared among 60 academic, government, and Indigenous representatives from 27 organizations from Venezuela, Brazil, and Guyana. The data, in the form of small group discussions, participatory drawings, whole group reflections, and videos, showed that although there was general acceptance about the central role of fire in traditional Indigenous livelihoods and its importance for protecting the biological and cultural diversity of ecosystems, there were also tensions around the past imposition of a dominant fire exclusion discourse of governmental institutions in Indigenous territories. Overcoming the gaps derived from different experiences and historical worldviews, and building mutual trust and respect were the main challenges when integrating multiple perspectives through the “intercultural interface” of institutions working on environmental management and governance. The elaboration of a common declaration and next steps in the framework of a “Participatory and Intercultural Fire Management Network”, created during the workshop to enhance a sustainable fire policy, revealed the conviction of working together for Indigenous fire management legitimization and strengthening from all participants of the three countries. Full article

Due to their porous structure, aqueous environment and dietary fiber nature arabinoxylan (AX) gels could have potential applications for colon-specific therapeutic molecule delivery. In addition, prebiotic and health related effects of AX have been previously demonstrated. It has been also reported that cross-linked AX can be degraded by bacteria from the intestinal microbiota. However, AX gels have not been abundantly studied as carrier systems and there is no information available concerning their capability to entrap cells. In this regard, probiotic bacteria such as Bifidobacterium longum have been the focus of intense research activity lately. The objective of this research was to investigate the entrapment of probiotic B. longum in AX gels. AX solution at 2% (w/v) containing B. longum (1 × 10⁷ CFU/cm) formed gels induced by laccase as cross-linking agent. The entrapment of B. longum decreased gel elasticity from 31 to 23 Pa, probably by affecting the physical interactions taking place between WEAX chains. Images of AX gels containing B. longum viewed under a scanning electron microscope show the gel network with the bacterial cells entrapped inside. The microstructure of these gels resembles that of an imperfect honeycomb. The results suggest that AX gels can be potential candidates for the entrapment of probiotics. Full article

In the present study water extractable arabinoxylans (WEAX) from a Mexican spring wheat flour (cv. Tacupeto F2001) were isolated, characterized and gelled and the gel rheological properties and microstructure were investigated. These WEAX presented an arabinose to xylose ratio of 0.66, a ferulic acid and diferulic acid content of 0.526 and 0.036 µg/mg WEAX, respectively and a Fourier Transform Infra-Red (FT-IR) spectrum typical of arabinoxylans. The intrinsic viscosity and viscosimetric molecular weight values for WEAX were 3.5 dL/g and 504 kDa, respectively. WEAX solution at 2% (w/v) formed gels induced by a laccase as cross-linking agent. Cured WEAX gels registered storage (G’) and loss (G’’) modulus values of 31 and 5 Pa, respectively and a diferulic acid content of 0.12 µg/mg WEAX, only traces of triferulic acid were detected. Scanning electron microscopy analysis of the lyophilized WEAX gels showed that this material resembles that of an imperfect honeycomb. Full article