Search Results (150)

The Mexican Tropical Pacific (MTP) is a key component of the Eastern Tropical North Pacific Oxygen Minimum Zone, yet its carbonate system variability remains poorly constrained. This study examines wind-driven circulation effects on dissolved oxygen (DO) and the carbonate system —dissolved inorganic carbon (DIC), total alkalinity (TA), total-scale pH (pH_T), partial pressure of CO₂ in seawater (pCO_2w) and air–sea CO₂ fluxes (FCO₂)— in the Gulf of Tehuantepec (GT) and Tehuantepec Bowl (TB). Hydrographic data and discrete water samples were collected at 50 oceanographic stations during March 2020. Principal Component Analysis (PCA) identifies wind-driven circulation as the primary control of biogeochemical variability. Tehuano wind events and mesoscale eddies promoted upwelling of low-oxygen (DO < 20 µmol kg⁻¹) and high-DIC (>2200 µmol kg⁻¹) waters to 50 m depth in the central GT, while downwelling conditions prevailed in the TB. Stoichiometric analysis revealed DIC-DO coupling (slope = −1.39). Overall, the MTP acted as CO₂ source (FCO₂ ranging from −1.92 to 24.11 mmol m⁻² d⁻¹), with enhanced emissions linked to eddy-induced upwelling. This study provides the first integrated characterization of the carbonate system across both the GT and TB. Full article

Background: Criminal justice relies on information from witnesses. Retrieval from episodic memory is cognitively demanding; thus, many interview protocols advocate techniques to support episodic retrieval mode, which is essential for obtaining detailed accounts. Currently, interviewers have two empirically validated techniques for triggering and scaffolding conscious remembering: Mental-Reinstatement-of-Context and Sketch-Reinstatement-of-Context. However, where neither is appropriate, there exist few alternatives. We report a potential future addition to the interviewer toolbox, aimed at reinstating context through self-directed verbal cueing, namely the Verbal-Reinstatement-of-Context. Methods: Using a between-conditions mock witness paradigm, we compared the interviewer-directed Mental-Reinstatement-of-Context technique with self-directed Sketch-Reinstatement-of-Context and Verbal-Reinstatement-of-Context cue techniques. Participants were interviewed 48 h after they had seen a mock robbery. Memory performance was analyzed for correct and erroneous recall, completeness, and accuracy. Results: Participants who self-generated retrieval cues recalled an average of 26% (Sketch-Reinstatement-of-Context) and 11% (Verbal-Reinstatement-of-Context) more correct information and were more complete and more accurate than those in the Mental-Reinstatement-of-Context condition. Improved recall was not accompanied by increased errors. Mean combined errors were an average of 34% and 22% lower (respectively) in the self-generated cue conditions. Conclusions: Consistent with prior research, self-generated retrieval cues were more effective than interviewer-initiated cues. Sketch-Reinstatement-of-Context and Verbal-Reinstatementme-of-Context conferred clear advantages, although Sketch-Reinstatement-of-Context was most efficient overall. For witnesses unable or unwilling to sketch, Verbal-Reinstatement-of-Context may be a viable alternative. Full article

Titanium oxide (TiO₂) is of great interest in solar cell manufacturing, hydrogen production, and organic compound photodegradation. The synthesis variables and methodology affect the morphology, texture, crystalline structure, and phase mixtures of TiO₂, which, in turn, affect the optical and catalytic properties of TiO₂. In this work, the effect of acetic acid as a catalyst and chelating agent on the morphology, texture, crystal structure, optical properties, and photocatalytic activity of TiO₂ samples obtained using the sol–gel method with sodium dodecyl sulfate (SDS) as a template was investigated. The results indicated that acetic acid not only catalyzes the hydrolysis of the TiO₂ precursor but also acts as a chelating agent, causing a decrease in crystallite size from 18.643 nm (T7 sample, pH = 6.8, without addition of acetic acid) to 16.536 nm (T2 sample, pH = 2). At pH 2 and 3, only the anatase phase was formed (T2 and T3 samples), whereas at pH 5 and 6.8, in addition to the anatase phase, the brookite phase (11.4% and 15.61% for samples T5 and T7, respectively) was formed. The band-gap value of TiO₂ decreased with decreasing pH during synthesis. Although the T2 sample had the highest specific surface area and pore volume (232.02 m²g⁻¹ and 0.46 gcm⁻³, respectively), the T3 sample had better efficiency in methylene blue dye photodegradation because its bird-nest-like morphology improved photon absorption, promoting better photocatalytic performance. Full article

The water sustainability in Chihuahua City is challenged by rapid urbanization, population growth, industrial expansion, and climate variability. This study examines how these factors impact water demand by analyzing six decades of local precipitation, extreme temperature, demographic, and water consumption data. Statistical methods (time series and gamma distribution with R-package) and spatial analysis using Landsat and Spot satellite imagery were employed. Chihuahua’s urban area grew at an average annual rate of 7.4% from 1992 to 2020. Minimum and maximum temperatures have increased by 0.07 °C and 0.05 °C per year, respectively, leading to more frequent heatwaves over the past 30 years. Since the 1990s, there has been a noticeable trend towards more frequent extreme precipitation events coinciding with a sustained rise in extreme temperatures. Urban expansion and rising temperatures have increased water consumption by approximately 40% per °C over the past 30 years, accelerating the depletion of groundwater reserves in the city’s three main aquifers. These trends highlight the urgent need for integrated urban planning and climate-adaptation measures to reduce vulnerability and ensure long-term water security for Chihuahua. Full article

This work assesses the viability of ultrafiltration (UF) membranes as a substitution for classic tertiary technologies for municipal wastewater (MWW) treatment. UF membranes can offer efficient MWW filtration, meeting quality standards regarding solids, bacteria, viruses and emerging pollutants, such as microplastics. All of these make UF not only an attractive competitor regarding tertiary treatments but also a potential quaternary treatment according to the latest legislation. Indeed, the achieved permeate quality meets the more stringent parameters for water reuse in agriculture according to the European standard (A-type water). The UF membrane’s feasibility when used as an MWW tertiary/quaternary treatment was assessed in a semi-industrial plant with commercially available industrial membrane modules under different operating conditions: (1) transmembrane flux, (2) air sparging intensity and filtration/relaxation periodicities, (3) the concentration of solids reached in the membrane tank and (4) the efficacy of chemically enhanced backwashing (CEB) to mitigate fouling. Increasing the air intensity (around 0.25 m³ m⁻² h⁻¹), increasing the solids concentration (3–4 g L⁻¹) and using acid chemicals for backwashing at low concentrations but high periodicities (about 25–50 ppm of HCl/citric acid at a pH of 2.5 once or twice every 15 days) displayed great effectiveness in minimizing fouling, which was found to be mainly reversible. Thanks to the stablished conditions, semi-industrial UF membrane filtration was possible for more than 30 days when operating at relatively high transmembrane fluxes (21.5 LMH), achieving an average transmembrane pressure of around 120 mbar with an extremely low fouling growth rate of 0.024 mbar d⁻¹. Full article

Environmental exposures throughout the life of the subjects (exposome) could have a negative effect on their health outcomes. From this perspective, analysis of volatile organic compounds (VOCs) in human exhaled breath is emerging as a non-invasive tool to identify and check exposure to harmful agents. Breath analysis is also a helpful technique for human metabolism assessment, which allows for examining the impact of environmental exposures on organisms (biomonitoring). In this paper, a comprehensive review has been carried out to assess the use of breath analysis by mass spectrometry-based technologies for monitoring environmental exposures. Records of the last 20 years from three databases (PubMed/Medline, Scopus, and Web of Science) have been evaluated independently by two reviewers. A total of 38 studies fulfilled the criteria for eligibility. It has been compiled information about environmental exposures that have been monitored by breath analysis using mass spectrometry-based analytical platforms, as well as the most commonly used protocols of breath sampling, analytical techniques, and statistical methods. In addition, special emphasis has been placed on the huge range of VOCs selected as potential markers of environmental exposures. Despite the potential of breath analysis for monitoring human exposure, further research is needed to identify useful markers to establish it as a routine tool. Full article

The Aurora kinase A (Aurora-A), overexpressed in cancer cells, represents a promising anti-cancer therapeutic target due to its role in mitotic progression and chromosome instability. Aurora-A contains a recently described drug pocket within its Targeting Protein for Xklp2 (TPX2) interaction site, offering a promising target for small-molecule disruption and selective inhibition. In this study, 1281 natural products from Argentina’s database (NaturAr), encompassing chemically diverse and structurally rich metabolites, were evaluated using a machine learning model based on molecular fingerprints and variational autoencoders (VAEs) to predict inhibitory activity with high-throughput efficiency. From this initial screening, 624 compounds were classified as active type against Aurora-A, and subsequently subjected to molecular docking using FRED software (v4.3.0.3) against the Aurora-A crystal structure (PDB: 5OSD), focusing on the TPX2-binding interface. Among them, 117 compounds with various scaffolds showed better binding scores than the co-crystallized ligand, highlighting their potential to interact with the druggable target site through stable and specific molecular contacts. This workflow effectively prioritized compounds of natural origin from Argentina for the discovery of new Aurora-A kinase inhibitors, demonstrating the value of integrating AI-driven screening with structure-based modeling. These findings highlight the identification of novel scaffolds with high binding potential, offering promising starting points for the development of selective Aurora-A inhibitors. Full article

Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring lung neoplasia in sheep caused by jaagsiekte sheep retrovirus (JSRV). JSRV infects alveolar type II pneumocytes (ATII) and club cells (CC), and the expression of viral oncoproteins induces a lung adenocarcinoma. The gross pathology of OPA exhibits differences in the anatomical patterns known as classical and atypical forms. Thirty natural OPA tumors, divided equally into early OPA tumors (Group A, GA), atypical tumors (Group B, GB), and classical tumors (Group C, GC), were obtained from adult sheep (2–9 years old). Tumor heterogeneity was studied comparing the histopathology (growth patterns, local invasion, mitotic figures, myxoid nodules), together with immunohistochemistry (IHC) using markers of JSRV-ENV, epithelial cells (ATII cells, CC, ki67), progenitor-stem epithelial cells (K5, p63, CD44), and the anterior grade protein 2 (AGR2). Papillary pattern was predominant in all groups. Lepidic pattern was also relevant in GA, and acinar pattern was relevant in GB. Low proliferation indexes and local invasion were observed in all groups. Myxoid nodules were few. IHC showed that all samples were positive for JSRV-ENV. Cell markers demonstrated that GA was different when compared to GB and GC, showing significantly the highest levels of CC, K5, and p63 positive tumor cells. There were no significant differences between GB and GC. The heterogeneity analysis of OPA tumors revealed that in early tumors, repair is important but is not reflected in classical or atypical different anatomical OPA forms. Full article

Prenatal exposure to air pollution is a major public health concern due to its potential to impair fetal brain development. This study examined whether maternal inflammatory and oxidative stress biomarkers mediate the association between trimester-specific air pollutant exposure during pregnancy and infant neurodevelopment at one year. We analyzed 87 mother–infant pairs from the OBESO perinatal cohort in Mexico City. Trimester-specific exposure to CO, PM₁₀, PM_2.5, SO₂, and O₃ was estimated using residential geolocation. Biomarkers were measured in the first and third trimesters by protocol, and intra-pregnancy change was calculated as Δ(3T–1T) for cytokines (IL-1β, IL-6, TNFα) and oxidative stress markers (malondialdehyde (MDA), protein carbonyls (PC), and total antioxidant capacity (TAC). Infant neurodevelopment at 12 months was assessed using Bayley-III. Exploratory mediation analyses were conducted, adjusting for gestational age at birth, pre-eclampsia, gestational diabetes, fetal growth restriction, marital status, mode of delivery, and infant sex; bootstrapping was applied to obtain robust estimates. Third-trimester CO exposure was associated with poorer receptive language (coef = 0.754, p = 0.02). PM_2.5 exposure showed direct effects on expressive language in the first (coef = 0.01, p = 0.04) and third trimesters (coef = 0.007, p = 0.015) in models including IL-1β. Third-trimester O₃ and SO₂ exposures were linked to lower expressive scores in models including TNFα (coef = 0.007, p = 0.02), MDA (coef = 0.008, p = 0.04), and PC (coef = 0.007, 95% p = 0.04). Meanwhile PM₁₀ exposure was associated with socio-emotional outcomes in models with IL-6 and TAC (coef = 0.003, p = 0.04). These findings indicate that maternal inflammation and oxidative stress biomarkers did not mediate the associations between prenatal air pollution exposure and infant neurodevelopment, and this study cannot elucidate their specific biological role in neurodevelopment. Full article

Paraoxonase 1 (PON1) is an antioxidant enzyme that plays physio-pathological roles. Prior in silico analysis revealed the presence of response elements of the nuclear receptor superfamily in the PON1 promoter, comparable to glucocorticoid receptors (GR), the vitamin D receptor (VDR), and the pregnenolone X receptor (PXR). The aim of this study was to evaluate the effects of 1α,25-dihydroxyvitamin D₃, a ligand specific to VDR, on the expression and activity of PON1 in hepatocarcinoma cells (HepG2 cells). PON1 activities (arylesterase/AREase and lactonase/LACase) were determined by spectrophotometry. Quantitative real-time PCR was used to evaluate the effect of VDR and PXR on the mRNA levels of PON1 and CYP3A4 genes. Molecular models and dynamics simulations were built using specialized software. Treatments with 1α,25-dyhydroxyvitamin D₃ (calcitriol), its active hormonal form, resulted in an induction of PON1 mRNA and AREase activity compared to control cultures. These results suggest that calcitriol plays a role in the regulation of PON1 transcription and provide evidence that this hormone increases PON1 levels in HepG2 cells. In addition, the molecular modeling suggests that calcitriol enhances PON1 activity and this increase could be caused by direct interaction on the PON1 protein. This study shows the effects of calcitriol on PON1 expression, proposing a new molecular mechanism for the transcriptional regulation of PON1 through a process linked to VDR activation and direct interaction of calcitriol on the PON1 protein. Full article

Aim: To assess oxidative–inflammatory biomarker prediction of incident CKD after 1-year follow-up in a population with overweight/obesity and metabolic syndrome. Methods: Prospective nested case–control study comprising 117 CKD incident cases and 117 matched controls free of CKD after 1-year follow-up conducted in 55–75-year-old participants. Controls were time-matched 1:1 to cases by intervention group, age (≤65 vs. >65 years), and sex. Serum creatinine (SCr), cystatin C (CyC), and urine albumin-to-creatinine ratio (UACR) were measured at baseline, and CKD Epidemiology Collaboration equations for Caucasians were used to assess SCr, CyC, and CyC-SCr-based estimated Glomerular Filtration Rate (eGFR). Baseline levels of malondialdehyde (MDA), carbonyls, tumour necrosis factor alpha (TNFα), interleukin (IL)-1β, IL-1ra, IL-6, monocyte chemoattractant protein 1 (MCP-1), and leptin were determined from fasting serum samples. An inflammatory-oxidative stress score based on these biomarkers was calculated. Incident CKD was defined by eGFR-SCr <60 mL/min/1.73 m², and/or UACR ≥30 mg/g in the absence of CKD at baseline. Results: UACR positively correlated with pro-inflammatory markers (IL-1β; TNFα) and oxidative damage marker (MDA); eGFR-cyC showed negative correlations with IL-1β and IL-1ra, and eGFR-SCr with leptin. The odds ratios (OR; 95% CI) for incident CKD in the highest vs. the lowest tertile of IL-1ra IL-6 and TNFα were (2.22; 1.22–4.04), (7.03; 2.88–17.14), and (3.79; 1.79–8.02), respectively. The inflammatory–oxidative stress score was associated with incident CKD (OR per 1-SD increment: 2.06; 1.49–2.83). Conclusions: Inflammatory/oxidative stress is associated with CKD incidence in individuals with high cardiovascular risk, underscoring the importance in identify early inflammation to prevent this disease. Full article

Hydrophobins are small, surface-active protein biosurfactants secreted by filamentous fungi with potential applications in industries such as pharmaceuticals, sanitation, and biomaterials. Additionally, hydrophobins are known to stabilize enzymatic processing of biomass for improved catalytic efficiency. In this study, Pichia pastoris was used to recombinantly express hydrophobin HFBI from Trichoderma reesei, a well-characterized fungal system used industrially for bioethanol production. Iterative optimization was performed on both the induction and purification of HFBI, ultimately producing yields of 86.6 mg/L HFBI and elution concentrations of 48 μM HFBI determined pure by SDS-PAGE, over a five-day methanol-fed batch shake flask induction regiment followed by a single unit operation multimodal cation exchange purification. This final purified material represents an improvement over prior approaches to enable a wider range of potential applications for biosurfactants. Full article

Neurodegenerative diseases affect millions worldwide and present an urgent challenge due to the aging of the population. Drug delivery to the brain is limited by the blood–brain barrier (BBB), inspiring the development of nanotransporters like phytosomes. This study aimed to develop phosphatidylcholine (PC)-based phytosomes incorporating macroalgae extracts. Some of them were functionalized with PEG and ApoE to enhance BBB passage. The phytosomes were characterized by the encapsulation rate, size, polydispersity index (PDI), zeta potential, and stability, with BBB passage tested in an in vitro model (transwell hCMEC/D3 cell model). The phytosomes showed high stability and effective extract binding (74.9–80.3%) over four weeks. Although ApoE functionalization did not significantly improve BBB crossing, all nanotransporters successfully traversed the BBB in the model. Full article

Arsenic contamination in aquifers poses a significant global health risk due to its toxicity and widespread presence in groundwater used for drinking. Although several approaches for arsenic removal exist, many are either expensive or logistically difficult. This study assesses the efficacy of native limestones from two arsenic-contaminated regions in Mexico as a sustainable treatment alternative. Tested in batch and column experiments using synthetic solutions, as well as natural and arsenic-enriched groundwater, the limestones were characterized mineralogically (XRD) and chemically (XRF). Surface area, particle size, average pore volume in rocks, and competing anions (i.e., bicarbonate and sulfate) in groundwaters played important roles in removal performance. The results show that smaller particle sizes improve arsenic retention. Up to 87.6% of the arsenic was removed from groundwater containing 1.29 mg/L of arsenic when treated with rock particles smaller than 0.062 mm. Natural groundwater, however, in general, exhibited lower efficiency than synthetic solutions due to anion interference. Although site-specific evaluations are essential, these results indicate that limestone may be a cost-effective and locally accessible solution for addressing arsenic (As) contamination in regions with abundant limestone outcrops. Full article

Photodynamic therapy (PDT) is a minimally invasive technique—used for the local eradication of neoplastic cells—that exploits the interaction of light, oxygen, and a photo-responsive drug called photosensitizer (PS) for the local generation of lethal ROS. Push-pull chromophores, that bear electron donor (D) and acceptor (A) groups linked through a π-electron bridge, are characterized by a non-homogeneous charge distribution in their excited state, with charge transfer from one extremity of the chain to the other one (Internal Charge Transfer—ICT). This phenomenon has a direct impact on the photophysical features of the push-pull compounds, as the bathochromic shift of the emission maxima and intersystem crossing (ISC) of the excited state are directly connected with the production of reactive oxygen species (ROS). In continuing our research regarding the synthesis and use of oligophenylene ethynylenes (OPEs) in PDT, two new push-pull glycosyl OPE-NOF and OPE-ONF—featuring electron-donor N,N-dimethylamino (N) and dimetoxyaryl (O) and acceptor tetrafluoroaryl (F) moieties on the OPE chain—have been efficiently prepared. The interchanged position of the D groups onto the conjugated skeleton was aimed to tune and optimize the push-pull effect, while the introduction of glucoside terminations was directed to give biocompatibility and bioaffinity to the chromophores. OPE-NOF, OPE-ONF, and the synthetic intermediates were fully characterized, and their photophysical properties were investigated by using UV-Vis absorption and emission spectroscopy. OPE-NOF showed a strong charge-transfer character and high PDT effect on HeLa cancer cells when irradiated with non-harmful blue light, causing massive cancer cell death. Full article