Search Results (298)

The northern Vietnam shelf, particularly the area adjacent to the Red River Fault Zone, is characterized by complex geology and active neotectonics. However, the patterns of degassing and the origins of hydrocarbon gases in this region remain poorly understood. In particular, the potential links between deep-seated fluid migration, fault systems, and gas anomalies in island groundwater systems have not been systematically investigated. This study presents preliminary results of dissolved methane, its homologues (C₂–C₅), helium, hydrogen, and carbon dioxide measurements in groundwater from Co To Island (Northern Vietnam), with the aim of identifying gas origins and assessing structural controls on fluid migration. A significant methane anomaly was discovered, with concentrations reaching up to 10% by volume in the northwestern part of the island. The hydrocarbon homologous series is traced up to pentane (C₅), and CO₂ content is also elevated, with a maximum of 5.4%. The average He concentration of 10.8 ppm significantly exceeds atmospheric equilibrium values, with maximum recorded concentrations of 18 ppm for He and 34.5 ppm for H₂. Stable carbon isotope analysis of methane (δ¹³C-CH₄ values ranging from −50.2‰ to −49.7‰ VPDB), combined with the presence of a complete C₁–C₅ hydrocarbon series and elevated mantle/crustal tracers (He, H₂), indicates a predominantly thermogenic/metamorphogenic origin for the gases, ruling out a purely biogenic source. The spatial distribution of anomalies is structurally controlled, closely associated with the NE-SW trending Co To Fault system and its intersections with subsidiary faults, as corroborated by recent electrical resistivity tomography data. These findings indicate intensive, focused gas leakage from a deep-seated source, likely related to thermogenic/metamorphic processes and active fault-mediated degassing. The results highlight the significant hydrocarbon potential of the region and underscore the critical role of neotectonic activity in controlling fluid migration pathways in island aquifer systems. Full article

Gelatin hydrolysate (GH), a bioactive compound derived from collagen, has demonstrated potential therapeutic benefits in various medical conditions. However, its effects on chronic cerebral hypoperfusion-induced vascular dementia remain underexplored. This study aimed to investigate the anti-oxidative stress effects of GH in alleviating brain damage and cognitive impairment in CCH-induced rats. Male Wistar rats underwent bilateral common carotid artery occlusion to induce CCH and were randomly divided into five groups: (1) sham, (2) 2-vessel occlusion (2VO), (3) 2VO + 250 mg/kg GH, (4) 2VO + 500 mg/kg GH, and (5) 2VO + piracetam. Treatments were administered for 35 days of post-operation. GH treatment significantly mitigated oxidative stress, as evidenced by reduced levels of reactive oxygen species (ROS), nitric oxide (NO), and the expression of 4-hydroxynonenal (4-HNE) and NADPH oxidase 4 (NOX4). Furthermore, GH exhibited antioxidant activity by upregulating superoxide dismutase (SOD) levels via nuclear factor E2-related factor 2 (Nrf-2) activation. This, in turn, reduced neuronal apoptosis by decreasing Bax and cleaved-caspase 3 levels and increasing Bcl-2 expression. Additionally, GH treatment ameliorated Tau protein hyperphosphorylation and improved synaptic function. Overall, GH exerted neuroprotective effects against oxidative stress-related neuronal damage and enhanced neuroplasticity, learning, and memory in rats with CCH-induced cognitive impairment. Full article

The conformational properties and intrinsic reactivity of unsaturated CH₂=C(R)XH systems (R = –H, –CH=CH₂, –C≡CH, –C≡N, –Cl, –phenyl, –cyclopentadienyl, –pyrrole; X = O, S, Se)—namely enols, enethiols, and eneselenols—have been investigated using G4 and CCSD(T) calculations. All compounds exhibit antiperiplanar (ap) and anticlinal (ac)-conformers that are nearly isoenergetic, as their relative stabilities are governed by subtle noncovalent interactions, which are analyzed in detail. Both conformers are therefore expected to coexist in the gas phase, and because the rotational barriers are very low, their interconversion is effectively barrierless under typical conditions. In contrast, the corresponding protonated species display significantly higher barriers, approximately three to five times larger. The keto–enol tautomerization involves activation barriers exceeding 180 kJ·mol⁻¹, confirming that, as in other keto–enol rearrangements, the process is not monomolecular. Protonation generally occurs at the methylene carbon, with the exceptions of the –C≡CH and –C≡N derivatives. Strong linear correlations are found among the proton affinities of the three families studied, which follow the trend: enols > enethiols > eneselenols. All systems behave as strong carbon bases; some are predicted to be 20–21 orders of magnitude more basic than ketene and 3–5 orders of magnitude more basic than vinylimine in terms of equilibrium constants. Deprotonation preferentially occurs at the X–H group in nearly all cases. The only exception is the cyclopentadienyl-substituted enol, for which deprotonation of the cyclopentadienyl moiety is favored due to enhanced aromatic stabilization of the resulting anion. Overall, acidity increases along the series O < S < Se. Full article

Introduction: Congenital central hypoventilation syndrome (CCHS) is a rare disorder characterized by an impaired ventilatory response to hypercapnia and hypoxia, particularly during sleep, and frequently associated with autonomic dysfunction. It is caused by pathogenic variants in the PHOX2B gene. Although CCHS is typically diagnosed in the neonatal period, milder forms may present later in infancy or childhood, often triggered by respiratory infections. Case presentation: We report the case of 16-month-old male diagnosed with CCHS following an episode of hypoxemic–hypercapnic respiratory failure during respiratory syncytial virus (RSV) infection. His medical history included neonatal respiratory distress requiring oxygen therapy and recurrent wheezing. At 15 months, he developed acute respiratory distress with severe hypercapnia (PaCO₂ 70 mmHg), requiring admission to the Pediatric Intensive Care Unit and invasive mechanical ventilation. Persistent sleep-related hypercapnia and hypoxemia prompted evaluation for central hypoventilation, confirmed by means of transcutaneous capnography and nocturnal pulse oximetry. Genetic testing revealed a de novo nonsense mutation in exon 1 of PHOX2B (p.Tyr14Ter). Brain magnetic resonance imaging showed diffuse white matter changes suggestive of gliosis. Further investigations identified early-onset systemic hypertension, requiring antihypertensive therapy. The patient was discharged on nocturnal non-invasive ventilation and enrolled in a neurodevelopmental rehabilitation program. Conclusions: This case highlights the phenotypic variability of CCHS and the importance of considering this diagnosis in children presenting with unexplained hypercapnia and sleep-related hypoxemia. It underscores the need for comprehensive autonomic evaluation, including blood pressure monitoring. The p.Tyr14Ter variant may allow partial protein function, potentially accounting for the relatively mild phenotype. Full article

This study investigates the potential influence of Saharan dust intrusions on the stable carbon isotopes of methane (CH₄) and carbon dioxide (CO₂), using continuous in situ measurements from the ICOS (Integrated Carbon Observation System) atmospheric station at the CNR-IMAA Atmospheric Observatory (CIAO) in Tito, Basilicata, southern Italy. The analysis builds upon the recent investigation of a two-month isotopic dataset (20 February–20 April 2025), which identified anomalous isotopic behavior in March, coinciding with three distinct dust events. The observations reveal shifts in δ¹³C–CH₄ values that align temporally with the dust intrusions, accompanied by a decrease in CH₄ mole fractions. Such patterns could suggest fractionation processes affecting CH₄, potentially driven by enhanced oxidation promoted by mineral aerosols. At the same time, δ¹³C–CO₂ shows a gradual decline, deviating from the typical springtime enrichment associated with intensified photosynthetic uptake of ¹²CO₂. This unexpected decrease suggests that dust-related radiative effects, particularly the attenuation of incoming solar radiation, may inhibit photosynthesis, thereby altering the isotopic composition of atmospheric CO₂. Consistently, CO₂ mole fractions exhibit a modest increase during periods of declining δ¹³C–CO₂, reinforcing the interpretation of reduced photosynthetic activity. These findings provide new observational data beyond existing studies from Atlantic regions and highlight the need for further research on the role of mineral dust in shaping greenhouse gas isotopic variability in the Mediterranean, where such events are frequent and climatically relevant. Full article

Background: Dupuytren’s disease (DD) is a fibroproliferative disorder of the palmar fascia that results in progressive digital flexion contractures. Various treatment strategies have been developed to restore extension, ranging from minimally invasive collagenase clostridium histolyticum (CCH) injection to more invasive surgical procedures such as open selective aponeurectomy. While CCH has gained widespread adoption due to its limited invasiveness and rapid recovery, questions remain about its long-term durability compared with open surgery (OS). This study aims to compare long-term outcomes of CCH injection and OS in patients with stage 2 or higher single-digit DD, focusing on recurrence, patient satisfaction, complications, and return to work at least 10 years after treatment. Methods: A retrospective cohort study was conducted on patients treated in 2012 with either CCH injection or OS. All patients had at least stage 2 DD and at least 10 years of follow-up. The primary outcome was to compare recurrence rates between the two patient cohorts. Secondary outcomes included visual analogue scale (VAS) satisfaction, Michigan Hand Questionnaire (MHQ) scores, complications, and time to return to work. Results: A total of 97 patients completed 10-year follow-up (60 OS, 37 CCH). Recurrence at 7 years was relatively similar between groups. However, a pronounced divergence emerged between 7 and 10 years. At 10 years, recurrence occurred in 10 patients in the OS group versus 15 in the CCH group, with statistically significant differences overall (p = 0.0175) and particularly in the PIP subgroup (p = 0.0041). VAS satisfaction at 10 years was higher after OS (7.9 ± 1.5) than after CCH (6.4 ± 1.6), and return to work was significantly faster after CCH. MHQ scores were comparable. Conclusion: Both treatments provided acceptable patient satisfaction at 10 years; however, OS yielded better long-term recurrence rates and fewer complications. Although CCH offers rapid recovery, its durability beyond 7 years appears markedly inferior. These findings reinforce the need for careful patient selection and long-term counseling when considering minimally invasive treatment. Full article

Background: Occipital nerve stimulation (ONS) is an effective therapy for patients with refractory chronic cluster headache (rCCH); however, it is not without complications, and to date, there are no conclusive findings regarding factors that would allow the prediction of treatment response. The primary objective of this study is to identify such factors to improve patient selection. Methods: This single-center prospective observational study will be conducted at the Department of Neurology, Hospital Universitario La Paz (Madrid, Spain). Given the low prevalence of rCCH, a convenience sampling approach will be adopted, with an expected enrollment of a minimum of 15 patients over 24 months of the study. The study is structured into three periods: Pre-ONS (pre-implantation), ONS (implantation), and Post-ONS (follow-up at 12 months). During the pre-implantation phase, patients will undergo a multidimensional assessment encompassing structural 3T brain magnetic resonance imaging (MRI), blood analysis (calcitonin gene-related peptide (CGRP), pituitary adenylate cyclase-activating peptide 38 (PACAP38), and vasoactive intestinal peptide (VIP)), neuropsychological evaluation, auditory evoked potentials, algometry (pressure pain threshold, temporal summation, conditioned pain modulation), and transcutaneous electrical nerve stimulation (TENS). Follow-up visits will be conducted at 3, 6, and 12 months post-implantation. Results: This study aims to identify biomarkers or their combinations capable of reliably predicting patients who would benefit from ONS. Conclusions: Through this multidimensional assessment, this study seeks to identify predictive factors of response to ONS, thereby improving patient selection, optimizing healthcare resources, and advancing the understanding of treatment response mechanisms. Full article

Nitrogen (N) deposition poses a multi-pronged threat to the carbon (C)-regulating services of moss understories. For forest C-cycle modeling under increasing N deposition, failure to mechanistically incorporate the moss-mediated processes risks severely overestimating the C sink potential of global forests. To explore whether and how N input affects the moss-mediated CH₄ and carbon dioxide (CO₂) fluxes, a five-year field measurement was performed in the N manipulation experimental plots treated with 22.5 and 45 kg N ha⁻¹ yr⁻¹ as ammonium chloride for nine years under a well-drained temperate forest in northeastern China. In the presence of mosses, the average annual CH₄ uptake and CO₂ emission in all N-treated plots ranged from 0.96 to 1.48 kg C-CH₄ ha⁻¹ yr⁻¹ and from 4.04 to 4.41 Mg C-CO₂ ha⁻¹ yr⁻¹, respectively, with a minimum in the high-N-treated plots, which were smaller than those in the control (1.29–1.83 kg C-CH₄ ha⁻¹ yr⁻¹ and 4.82–6.51 Mg C-CO₂ ha⁻¹ yr⁻¹). However, no significant differences in annual cumulative CO₂ and CH₄ fluxes across all treatments occurred without moss cover. Based on the differences in C fluxes with and without mosses, the average annual moss-mediated CH₄ uptake and CO₂ emission in the control were 0.77 kg C-CH₄ ha⁻¹ yr⁻¹ and 2.40 Mg C-CO₂ ha⁻¹ yr⁻¹, respectively, which were larger than those in the two N treatments. The N effects on annual moss-mediated C fluxes varied with annual meteorological conditions. Soil pH, available N and C contents, and microbial activity inferred from δ¹³C shifts in respired CO₂ were identified as the main driving factors controlling the moss-mediated CH₄ and CO₂ fluxes. The results highlighted that this inhibitory effect of increasing N deposition on moss-mediated C fluxes in the context of climate change should be reasonably taken into account in model studies to accurately predict C fluxes under well-drained forest ecosystems. Full article

This study addresses the challenge of data scarcity in research on the migration patterns of shallow gas in submarine sediments. Taking the northern Hangzhou Bay area of the East China Sea as an example, we integrate borehole core geophysical surveys and geochemical data to elucidate the migration and fractionation mechanisms of shallow biogenic gas. A three-zone conceptual model—“disturbed zone–active zone–residual zone”—dominated by lithology-controlled migration is established, revealing the dominant roles of gas escape, mixing-homogenization, and adsorption fractionation in heterogeneous sedimentary systems. The results show that high-permeability sand layers can act as adsorption-fractionation windows, causing significant enrichment in δ¹³C-CH₄ (–57.4‰). We propose an analytical framework of “zonal verification–mechanism tracing”, which overcomes the limitations of traditional Rayleigh fractionation models and enables accurate interpretation of gas migration patterns in heterogeneous systems using limited data such as δ¹³C-CH₄ and CH₄ concentration. This provides a new paradigm for engineering surveys and risk assessment in low-data-density contexts. The findings indicate that the shallow seepage zone poses low engineering risks, while the residual zone serves as an indicator of depleted gas reservoirs. The proposed analytical approach can be extended to preliminary submarine engineering surveys and hazard assessments in other regions. Full article

Background/Objectives: The present study aimed to investigate how the changes in the inclination of the upper and lower incisor regions during the alignment phase of orthodontic treatment (OT) without premolar extraction influence the height and thickness of the gingiva around these incisors. Methods: This prospective clinical study included 62 patients undergoing OT without premolar extraction. Cone beam computed tomography and intraoral 3D scans were taken before and after the alignment phase, and superimposed using specialized software. The changes in the inclination of each tooth, alveolar bone height (ABH), clinical crown height (CCH), and gingival thickness on the level of the cement–enamel junction (CEJ) and 1 mm below it were determined on both tooth sides. Results: The alignment phase of OT was accompanied by an increase in CCH on the buccal side of both upper and lower incisors. In contrast, on the palatal/lingual sides, either a decrease or an increase in CCH was observed, depending on the direction and amount of the changes in the inclination. Furthermore, in many cases, a decrease in the gingival thickness was observed, which was especially pronounced on the palatal side of the upper incisors after proclination. The changes in the CCH and gingival thickness on the palatal/lingual sides exhibited a weak to moderate correlation with the changes in the inclination. In addition, a very weak to weak correlation between the changes in gingival parameters and ABH was observed. Conclusions: Our data suggest that there is some soft tissue remodeling during the alignment phase of OT, and the changes in soft tissue parameters exhibit some dependency on the changes in inclination. Potential changes in the soft tissue should be considered in planning orthodontic treatment. Full article

A detailed investigation of the structure–property relationships of three-antennary oligoglycines in aqueous solutions is performed. Two representatives of these substances are investigated: CH₃C(-CH₂-NH-Gly₅)₃ and CH₃C(-CH₂-NH-Gly₇)₃. The aim is to clarify the effect of molecular peculiarities and the concentration of the oligoglycines on bulk-solution performance and on adsorption-layer properties at the solution–air interface. This study is focused on the clarification of the conditions for the onset of bulk and interfacial supramolecular species in the aqueous environment. The presence of oligoglycine antennae attached to a common carbon-atom center allows the formation of highly coordinated intra- and intermolecular ‘click-clack’ interactions and presumes the possibility for the development of extended H-bonded networks, e.g., in the form of Polyglycine II motifs. A combined study protocol, including dynamic light scattering, profile analysis tensiometry, and microscopic thin-liquid-film techniques, is applied. The results allow the drawing of essential conclusions about the possible coupling mechanism of bulk and interfacial phenomena. The outcomes give grounds to advance the following hypothesis: due to the synchronized action of noncovalent interactions, three types of tectomeric structures may appear—dimers, gel-like elements, and disk-like supramolecular entities. Options for fine-tuning of the tectomer formation in aqueous solutions are presented, and possible application routes are outlined. Full article

Chitin-derived biomass carbon materials are promising supercapacitor electrode materials due to their wide availability, low cost, high specific surface area, and nitrogen doping capability. However, their practical application is limited by insufficient conductivity and cyclic stability, often requiring functional modification or integration with complementary materials. In this study, we present a novel strategy by incorporating copper sulfide (Cu₂S) into a chitin-based carbon matrix. Cu₂S, known for its high intrinsic conductivity, excellent electroactivity, and theoretical specific capacity (~335 mAh·g⁻¹), was uniformly doped into the three-dimensional carbon aerogel framework derived from chitin nanofibers (ChNF) through sol–gel, freeze-drying, and high-temperature carbonization processes. The resulting chitin-based carbon/Cu₂S composite aerogel (CChNF/Cu₂S) exhibited a hierarchical porous structure with Cu₂S nanoparticles (20–30 nm) uniformly distributed on the carbon fiber surface. Electrochemical tests demonstrated its excellent performance, achieving a specific capacitance of 852 F·g⁻¹ at 1 A·g⁻¹, highlighting the synergistic effects of the conductive Cu₂S and nitrogen-doped carbon framework for high-performance supercapacitor applications. Full article

Upon reaction of dirhodium tetraacetate ([Rh₂(μ-O₂CCH₃)₄]) and some [Rh₂(μ-O₂CCH₃)₄] derivatives with proteins, dimeric Rh-Rh units (diRh) or monometallic moieties can bind the side chains of His, Cys, Met, Asp, Asn, Arg and Lys, and the C-terminal carboxylate. However, structural data on the interaction between the diRh center and Cys and Met side chains within the protein environment are still missing. Here, we report the X-ray structure of the adduct that [Rh₂(μ-O₂CCH₃)₄] forms with C-phycocyanin from Galdiera phlegrea at 2.17 Å resolution. Twelve diRh binding sites were found on the protein structure, two for each (αβ) unit. Dimetallic fragments were observed close to the side chains of Met30 of β-chains and of Cys73 of α-chains. To the best of our knowledge, the results provide the first unambiguous crystallographic observation of the diRh center binding to Met and Cys protein residues. DiRh binding does not alter overall protein structure and stability. This result will help in the design of new dirhodium-based artificial metalloenzymes. Full article

The antiarrhythmic drug amiodarone is toxic to yeast cells due to provoking Ca²⁺ entry into cytosol. Here we show that in Ogataea parapolymorpha, the loss of Cch1 or Mid1, which are the primary components of the high-affinity Ca²⁺ uptake system (HACS), leads to a delay in the rise of cytosolic Ca²⁺ concentration ([Ca²⁺]_cyt) in response to amiodarone. This has negligible effect on the ability of the strain with the unaffected Ca²⁺ sequestration system to grow in the presence of amiodarone. Inactivation of the PMC1 gene encoding the Ca²⁺ ATPase involved in the cytosolic Ca²⁺ sequestration in the vacuole dramatically increases sensitivity to amiodarone, while inactivation of CCH1 or MID1 suppresses it. This correlates with a substantially lower [Ca²⁺]_cyt rise in response to amiodarone when the genes encoding the HACS components are inactivated in the mutant lacking Pmc1. Similarly to sodium dodecyl sulfate, which has also been shown to increase [Ca²⁺]_cyt, amiodarone causes activation of the Hog1 protein kinase involved in the cell cycle regulation. The role of HACS in the amiodarone-induced Ca²⁺ influx is discussed. Full article

Biomolecules of microbial origin are gaining attention for their use in various industries, including cosmetics, due to their broad bioactivities, peculiar properties, and sustainability. This study aimed to develop a novel, eco-friendly nanoemulsion from fungal chitosan hydrochloride (ChC), Pseudomonas aeruginosa biosurfactant (PaB), and grape seed oil (GSO), and to assess its antimicrobial action, biofilm control, and biocompatibility. High-energy emulsification was performed to produce the nanoemulsion (CCh-PaB-GSO), which was characterized by FTIR. Its stability was monitored for 30 days via DLS, zeta potential (ZP), and PDI. The minimum inhibitory concentration (MIC) for cariogenic Streptococcus species, inhibitory fraction concentration (FIC), influence on exopolysaccharide (EPS) quantification produced by bacteria, bacteria’s cell wall hydrophobicity, and biofilm control were determined. Biocompatibility was assessed using the HET-CAM technique by determining the irritation potential. FTIR analysis confirmed the formation the interaction between the substances that compound the nanoemulsion. The CCh-PaB-GSO had nanometric micelles (169.5–203.4 nm), PDI (0.241–0.271), and a positive ZP (+20.25 to +31.94 mV). It showed a consistent MIC (2.0 mg/mL CCh, 0.1 mg/mL PaB, and 3.2 mg/mL GSO) for all tested Streptococcus species and an indifferent interaction effect, FIC (1.32). At sub-MIC, the CCh-PaB-GSO effectively reduced EPS and microbial cell wall hydrophobicity, inhibiting biofilm adhesion. The CCh-PaB-GSO demonstrated biocompatibility with no signs of irritation. In conclusion, the ChC-PaB-GSO system forms an effective and stable nanoemulsion with potential for application as an eco-sustainable and biocompatible product for caries control. Full article