Search Results (880)

Euphorbia tirucalli, commonly known as Aveloz, is widely used in Brazilian folk medicine for its purported antibacterial, antiviral, and antitumoral properties. However, scientific evidence regarding its systemic in vivo effects, particularly on the cardiovascular system, remains limited. This study investigated the impact of oral E. tirucalli latex ingestion on cardiac hemodynamics and associated molecular alterations in normotensive Wistar rats. Animals received water (control) or E. tirucalli latex (13.47 mg/kg) by oral gavage for 15 days. Hemodynamic parameters were assessed through noninvasive blood pressure monitoring and direct measurements of left ventricular systolic (LVSP) and end-diastolic pressures (LVEDP), cardiac cycle duration, rates of pressure development (dP/dt_max and dP/dt_min), and the left ventricular relaxation constant (Tau). Oxidative stress and inflammation were evaluated by plasma advanced oxidation protein products (AOPP) and myeloperoxidase (MPO), respectively, while reactive oxygen species production and apoptosis were analyzed in isolated cardiomyocytes. Although systemic blood pressure remained unchanged, E. tirucalli increased LVSP, LVEDP, cardiac cycle duration, and dP/dt_max, while reducing Tau. These alterations were accompanied by elevated AOPP and MPO levels, increased cardiomyocyte hydrogen peroxide, and higher rates of early apoptosis, indicating that E. tirucalli latex alters cardiac hemodynamics and promotes oxidative and inflammatory cardiac injury. Full article

Streptococcus canis is an opportunistic pathogen that colonises the mucosal surfaces and skin of its host. Though predominantly a veterinary pathogen affecting cats and dogs, S. canis has also been identified as the causative agent in severe human disease. IdeC is a secreted cysteine protease of S. canis that has a high specificity for IgG, cleaving at the hinge region. We show here that the protein binds back to the surface of the bacteria. Additionally, the protein contains a conserved Arg-Gly-Asp (RGD) motif, the minimal peptide sequence required for integrin binding. Several bacterial proteins containing RGD motifs have been implicated in adhesion and invasion of host cells. This RGD motif along with the ability of IdeC to bind back to the bacterial surface after secretion is the basis for this study into a potential secondary function of IdeC in adhesion and/or invasion. We used protein-coated latex beads to investigate the interaction of IdeC with epithelial and endothelial cells and, further, the extent to which the RGD motif is involved in this interaction by utilising an RGD->RGE recombinant protein. We also report here that the deletion of IdeC in S. canis results in a significant reduction in invasion into epithelial cells. Full article

To address the pronounced self-aggregation of highly loaded silica in the aqueous phase and the substantial filler loss occurring during the flocculation stage of latex compounding, this study introduces disaggregated and activated sepiolite possessing a spatial confinement effect as both a suspension stabilizer and a synergistic reinforcing component. On this basis, a multiscale natural rubber (NR)/silica/sepiolite composite system was constructed via a latex compounding route. Rheological characterization combined with static sedimentation observations revealed that the percolation threshold of the sepiolite is approximately 0.8 wt%. When the sepiolite content exceeds 1.0 wt%, its fibrous morphology enables the formation of a continuous three-dimensional network, which physically constrains silica particles and effectively suppresses their sedimentation and self-aggregation in the aqueous medium. Guided by this percolation behavior, a stable silica/sepiolite hybrid slurry was subsequently wet-mixed with natural rubber latex, and the influence of sepiolite loading on silica retention during flocculation, as well as on the resulting composite properties, was systematically examined. The results demonstrate that incorporation of sepiolite reduces filler loss during flocculation, with the loss rate decreasing from 4.7% to 1.1%. The Payne effect, SEM, dynamic and static mechanical analyses indicate that an appropriate sepiolite dosage promotes dispersion of silica within the rubber matrix while simultaneously strengthening filler–rubber interfacial interactions. Accordingly, tensile and tear strengths are increased from 32.1 to 35.5 MPa and from 92.3 to 133.4 N·mm⁻¹, respectively, while wet skid resistance is preserved and both rolling resistance and wear resistance are further improved. The findings of this work establish a practical and efficient strategy for the wet preparation of high-performance NR/silica composites. Full article

Guar gum (GG), a typical biopolymer, has found widespread use in packaging applications due to its biodegradability, non-toxicity, and low price. However, the further application of GG is significantly limited by its poor flexibility and water resistance. In this study, GG/natural rubber (NR) films were prepared by thermo-compressing hand-kneaded pastes made from GG powder and fresh NR latex. Various NR contents—5, 10, 20, and 40 wt%—were investigated. Water-resistant properties were determined by moisture absorption, water dissolution, surface wettability, and water vapor permeability. Fourier transform infrared spectroscopy indicated interactions between the dispersed NR phases and the GG matrix. Scanning electron microscopy revealed distinct phase separation between the GG and NR phases in the films. All GG/NR films exhibited excellent interfacial adhesion between GG and NR phases. Tensile results indicated that an increase in the amount of NR in the GG-based films led to a decrease in both maximum tensile strength and Young’s modulus, while elongation at break increased. GG/40% NR films exhibited an elongation at break of 17.5%, which is a substantial increase of 415% compared to pure GG films. The addition of NR showed improved water-resistant properties of GG-based films; however, the rate of biodegradation during soil burial decreased as the NR ratios increased. These thermo-compressed GG/NR blends hold promise as sustainable alternatives to single-use plastic packaging applications. Full article

A new strategy to reduce the morbidity and mortality associated with invasive Streptococcus agalactiae (Streptococcus group B, GBS) diseases encompasses the development of vaccines. Candidate vaccines at different stages of clinical trials have been developed on capsular polysaccharides or protein antigens. We studied 328 GBS isolates identified using routine microbiological tests, latex-agglutination, and PCRs. The samples were categorised into two main groups: vaginal (69.2%) and extra-vaginal (30.8%). The molecular serotyping and target gene factors were determined using singleplex or multiplex PCRs. The most common serotypes identified were Ia (24.7%), V (22.0%), and III (18.9%). Serotypes I–V constituted a total of 89.0%. The non-typeable were 9.8%. The frequency of genes included in the recombinant GBS-NN (rib + bca) and GBS-NN2 (epsilon + alp2/3) vaccines were 54.3% and 40.8%. We noted a significant prevalence in the distribution of serotypes II, III, and non-typeable in GBS-NN, whereas serotypes Ia and IV were predominant in GBS-NN2. The serotype prevalence identified in our research was consistent with the data from our region and confirmed the predominance of the six main serotypes included in the hexavalent conjugated vaccine. We highlighted the importance of the combined administration of both protein vaccines, ensuring optimal vaccine coverage. Full article

Concentrated natural rubber skim latex is a sustainable, value-added product derived from natural rubber latex processing, offering high rubber content, fine particle size, and shorter polymer chains compared to pure latex, making it suitable for diverse industrial applications. This study employed an environmentally friendly ultrafiltration method using composite membranes composed of polyvinylidene fluoride (PVDF), titanium dioxide (TiO₂), and polyvinylpyrrolidone (PVP) to concentrate skim latex without hazardous chemicals. The process generated two fractions: concentrated skim latex and skim serum. Membrane performance and fouling behavior were evaluated using FESEM-EDX and FTIR. Post-filtration analysis revealed significant latex particle deposition on the membrane surface, with elemental mapping confirming the presence of organic and inorganic residues. FTIR spectra indicated interaction between latex components and membrane functional groups, though the membrane’s structural integrity remained intact. Sodium dodecyl sulfate (SDS) was assessed as a cleaning agent and demonstrated the effective partial restoration of membrane performance, as confirmed by flux recovery (PVDF-PVP-TiO₂ membrane recovered to a slightly higher flux of 7.35 L/m²h). These results highlight the membrane’s durability, fouling characteristics, and cleaning potential, supporting its reusability in latex processing. This study contributes to the development of sustainable separation technologies in the rubber industry, promoting circular economy and zero-discharge practices. Full article

Objectives: This study aims to define the surgical anatomy, technical feasibility, advantages, and limitations of the TPPA through detailed cadaveric dissection and a representative clinical case, evaluating its potential as a safe and effective alternative to traditional approaches to the mesiotemporal lobe. Methods: A cadaveric dissection was performed on one adult head injected with colored latex, using standard microsurgical instruments and high-definition video documentation. Each procedural step was recorded and illustrated with cadaveric photographs. Additionally, a clinical case of mesiotemporal cavernous hemangioma resected via TPPA is presented, including an operative video. Results: The dissection demonstrated a direct and safe trajectory to the amygdala and hippocampal head, with clear identification of key vascular and white matter landmarks. In the clinical case, the lesion was completely resected with no postoperative neurological deficits. Conclusions: The TPPA represents a novel microsurgical corridor to the mesiotemporal region, minimizing cortical disruption, Sylvian fissure dissection, and manipulation of middle cerebral artery branches. Although its exposure is limited posteriorly, the TPPA could offer an optimal balance between functional preservation and surgical accessibility, constituting a valuable addition to the modern microsurgical armamentarium. Full article

Cutter soil mixing (CSM) is a widely adopted construction technique for forming waterproof diaphragm walls in underground engineering. However, cement slurry is prone to dispersion loss and performance degradation in moving water, making it difficult to meet engineering requirements. In this study, based on the characteristics of the CSM method in dynamic water environments, ordinary Portland cement is used as the main material, and hydroxypropyl methyl cellulose (HPMC), redispersible latex powder, polypropylene fiber and a polyether defoamer are added to improve it. The influence of each component on the performance of the new material is investigated, and a new CSM material suitable for dynamic water environments is developed. The material has good stability and suitable fluidity, controllable setting time, good anti-dispersion performance in dynamic water. The optimal mix ratio is as follows: water–cement ratio of 1; HPMC 1.4%; redispersible latex powder 3%; polypropylene fiber 0.4%; and polyether defoamer 0.8%. Field tests show that the new grouting material applied to CSM waterproof curtain construction results in a leak-free wall with excellent waterproofing performance, which verifies its engineering feasibility and provides a technical reference for the application of the CSM method in dynamic water environments. Full article

Encapsulated probiotics, which are promising approaches for improving aquaculture species’ performance and health, have incompletely characterized dose-dependent physiological and immunological effects. This study represents the first report evaluating the probiotic efficacy of a novel encapsulated Lysinibacillus sp. PWR01, originally isolated from rubber latex nodules, in Nile tilapia (Oreochromis niloticus). A total of 300 Nile tilapia (10.80 ± 0.07 g) was allocated to four experimental groups receiving 0, 10⁴, 10⁵, and 10⁶ CFU/g of encapsulated Lysinibacillus sp. PWR01 in their diet. At 8 weeks of the feeding trial, growth performance, feed utilization, serum antioxidant status, intestinal bacterial counts and immune-related gene expression were analyzed. Results demonstrated that fish fed 10⁶ CFU/g achieved a final weight of 51.48 g, representing a 9.88% increase compared with the control (46.85 g), while weight gain (WG) improved by 12.82% and specific growth rate (SGR) by 6.34%. Feed conversion ratio (FCR) was reduced by up to 18.42% at 10⁵ CFU/g relative to the control. Encapsulated groups enhanced serum superoxide dismutase activity without altering malondialdehyde levels, increased total intestinal bacterial and lactic acid bacteria counts, and selectively upregulated TLR2 and MHC II mRNA transcript levels. Histological analysis further revealed increased intestinal villus height and width in encapsulated-fed groups, while liver architecture remained normal across treatments. Multivariate analyses demonstrated strong positive associations among growth performance, gut microbiota enrichment, and immune gene expression. Resistance to Aeromonas hydrophila infection was significantly improved at higher dietary doses, with post-challenge survival reaching 61.67–75% in supplemented groups versus 45.00% in controls. These findings demonstrate that latex-derived Lysinibacillus sp. PWR01 acts as a strain-specific immunomodulatory probiotic that enhances growth, antioxidant capacity, microbial community balance, and disease resistance to Nile tilapia. Future studies should investigate the role of the Nrf2 antioxidant pathway, clarify TLR2-mediated immune signaling, and assess gut microbiota–immune system interactions within commercial-scale production systems. Full article

Swim bladders in some teleost fish can act as gas-filled cavities that oscillate under acoustic pressure and transfer the sound energy to the inner ears. Quantifying the resonance frequency and damping of these oscillations is useful for linking swim bladder mechanics to hearing-related and behavioural questions, but many established direct-measure approaches have relied on open-water deployments and careful avoidance of boundary reflections, making experiments logistically demanding and difficult to reproduce (e.g., requiring deep-water sites, careful control of surface/boundary reflections, and complex deployment geometries). This study presents a compact laboratory methodology for estimating swim bladder resonance properties using a closed, fully water-filled, stainless-steel impedance tube. Broadband pseudorandom excitation is applied via an end-plate shaker, and the acoustic response of the system is recorded using wall-mounted hydrophones. Resonance peaks are identified using power spectral estimates of recorded signals, allowing resonance frequency and quality factor to be extracted from the peak location and −3 dB bandwidth. The approach is first established using inflated latex balloons as surrogate encapsulated gas cavities, providing a controlled benchmark for repeatability and interpretation. It is then applied to recently euthanised brown trout (Salmo trutta), where clear resonance features attributable to the swim bladder are observed and show systematic variation with body size. A coupled finite element model reproduces the principal resonance behaviour under the experimental loading and supports interpretation of the measured peaks as swim bladder resonance. The results provide a validated foundation for subsequent non-invasive measurements on live, free-swimming fish, as well as for future applications where swim bladder condition may be relevant to management or conservation. Full article

The valorization of agro-industrial byproducts as sources of functional polysaccharides is a promising strategy for developing sustainable materials. In this study, cellulose was extracted and purified from rice husk and apple pomace through sequential alkaline and bleaching treatments. Then it was chemically modified via TEMPO-mediated oxidation to obtain cellulose nanofibers (TOCNFs) with cellulose yields ranging from 23.8 to 32.4% for rice husk and 9.3–13.8% for apple pomace. Owing to its higher recovery and structural regularity, rice husk was selected for surface modification with 3-aminopropyltriethoxysilane (APTES). The resulting TOCNFs exhibited an average width of 8 nm and a carboxyl content of 0.48 mmol g⁻¹. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nitrogen determination (1.72 mg g⁻¹) confirmed the presence of aminosilane functionalities. APTES-modified TOCNFs were incorporated as active components to develop hybrid poly(vinyl acetate) (PVA) adhesives synthesized via in situ heterogeneous water-based polymerization. The influence of TOCNF surface chemistry and sodium dodecyl sulfate (SDS) on latex particle size, rheological behavior, and adhesive performance was systematically investigated. Latex particle size increased from 193 nm (PVA-SDS) to 625 nm with TOCNF-APTES and decreased to 247 nm upon SDS addition. Rheological analysis revealed pronounced shear-thinning behavior associated with the formation of percolated nanofibrillar networks, with low-shear viscosity increasing up to 477 Pa·s for TOCNF–APTES and decreasing to 370 Pa·s with SDS. Lap-shear testing (ASTM D905) showed substantial improvements in adhesive strength, reaching up to 250 kPa compared to PVA-SDS. These results demonstrate that surface-modified CNFs act not only as mechanical reinforcements but also as interfacially active components governing polymerization behavior, rheology, and adhesive performance. This exploratory study provides a proof-of-concept for the development of sustainable wood adhesives from agro-industrial byproducts. Full article

This study examines the combined effects of styrene–butadiene rubber (SBR) latex and fiber reinforcement on the mechanical and electrical properties of a high-performance fiber-reinforced composite (HPFRC). Mixtures incorporating steel fibers (SF, 0–4.5%), carbon fibers (CF, 0–1%), and hybrid SF/CF systems were evaluated, with 10–20% of the mixing water replaced by SBR. Electrical resistivity, rheological behavior, mechanical properties, and durability-related parameters were assessed and compared with plain and fiber-reinforced mixtures. Results showed that SBR significantly improved rheological behavior, flexural performance, durability, and interfacial bonding, while moderately enhancing compressive strength. The incorporation of fibers led to reduced electrical resistivity, with CF being more effective than SF, and the lowest resistivity of 4 Ω·m was achieved using a hybrid system of 0.25% CF and 1.5% SF. The addition of SF up to 1.5% increased compressive strength by up to 21%, whereas CF at 0.5% yielded the highest strength of 120 MPa. Durability indicators, including water absorption, sorptivity, and ultrasonic pulse velocity, were significantly improved at low SBR and fiber dosages. Interfacial treatment with SBR enhanced slant shear and pull-off strengths by up to 75% and 121%, respectively, confirming the effectiveness of polymer modification for multifunctional and repair-oriented HPFRC applications. Full article

Introduction: Fourier-transform infrared spectroscopy (FTIR) is a key technique in the characterization of biomaterials, allowing the identification of functional groups and the verification of bioactive compound incorporation in nanostructured systems. In this study, the spectral signature of raw materials used in the formulation of a nanoemulsion with curcumin, sunflower oil, annatto oil, and Cremophor applied in the production of a dressing consisting of a natural latex biomembrane (Hevea brasiliensis) was evaluated. Methodology: FTIR spectra were obtained from isolated raw materials (curcumin, vegetable oils, and Cremophor) and from the curcumin-containing nanoemulsion formulation, aiming to compare their spectral profiles and identify possible chemical interactions. Results: Curcumin showed characteristic bands around 3328–3508 cm⁻¹ (–OH), 1637 cm⁻¹ (C=O and conjugated C=C), and 1505 cm⁻¹ (aromatic ring), confirming its polyphenolic structure. Sunflower oil exhibited an intense peak at 1744 cm⁻¹ (ester carbonyl), associated with its triglyceride composition, while annatto oil showed a band at 1633 cm⁻¹ (conjugated C=O), indicative of bixine and carotenoids. Cremophor presented peaks at 3460 cm⁻¹ (–OH) and 1726 cm⁻¹ (C=O), typical of ethoxylated surfactants. In the curcumin-containing nanoemulsion, the Cremophor spectral profile predominated, but new bands between 1511 and 1637 cm⁻¹, associated with curcumin, confirmed its incorporation into the matrix. Conclusion: The FTIR results confirmed the preservation of the spectral signatures of the raw materials and the successful integration of curcumin into the nanoemulsion, reinforcing its potential for application in biomaterial-based dressings Full article

The presence of Silba adipata in countries outside its native range has raised increasing concern among fig (Ficus carica L.) producers due to its growing economic importance. Information on this lonchaeid remains scarce and is frequently fragmented across regional reports, technical documents, and isolated scientific studies. The lack of consolidated and reliable knowledge on S. adipata, together with its sporadic impacts on figs and frequent confusion with closely related species, has hindered the development of effective and sustainable management strategies. Here, we provide a comprehensive synthesis of the current geographic distribution of S. adipata and its expansion into new areas, addressing diagnostic aspects and potential misidentifications reported in the literature that have the potential to confound distribution records and assessments of its pest status. We critically review current knowledge of the biology, ecology, and behavior of S. adipata, together with existing and emerging management and control approaches, including cultural practices, monitoring tools, mass trapping strategies, and biological- and chemical-based tactics. The strengths and limitations of these approaches are discussed in the context of their applicability to fig production systems. Advancing the management of S. adipata requires not only accurate species identification and evaluation of conventional control methods, but also a deeper understanding of its ecology and sexual behavior. Addressing these knowledge gaps will be essential for the development of innovative, effective, and environmentally sustainable management strategies for this emerging pest. Full article

Legionella species are ubiquitous bacteria found worldwide in water, moist environments, soils, and compost. Infection occurs through the inhalation of aerosols, leading to either Pontiac fever or Legionnaires’ disease (LD). Current routine diagnostics typically combine culture-based isolation with Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for species identification and the Latex Agglutination Test (LAT) for serotyping. However, this workflow is fragmented: MALDI-TOF MS lacks serogroup-specific resolution, while LAT relies on subjective visual interpretation. Therefore, this study evaluated Fourier-transform infrared spectroscopy (FT-IR) as a rapid, high-resolution typing method for Legionella isolates to assess its potential as a single-step diagnostic tool. A total of 200 clinical and environmental Legionella isolates were analyzed using FT-IR, including L. pneumophila serogroups (SG) 1–15 and various non-pneumophila species. Spectral data were analyzed using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA). While MALDI-TOF MS provided accurate species identification, FT-IR spectroscopy demonstrated superior typing capabilities by successfully distinguishing L. pneumophila SG 1 distinct from the SG 2–15 complex and allowing for clear discrimination of most non-pneumophila species. Additionally, FT-IR resolved isolates that showed ambiguous or non-reactive results in LAT. These findings demonstrate that FT-IR overcomes the serotyping limitations of MALDI-TOF MS and offers a more objective, cost-efficient extension to the current multi-step routine, potentially closing the diagnostic gap between simple species identification and deep strain characterization. Full article