Investigating the adsorption potential of char derived from waste latex for methylene blue removal.

This study presents the adsorption of methylene blue (MB) dye using latex char derived from pyrolysis of latex gloves. The adsorption process was investigated systematically using Response Surface Methodology (RSM) with a Central Composite Design (CCD). The effects of four key variables, namely pH, time, temperature, and adsorbent dosage, were studied using a factorial design enriched with center points and axial points. Experimental data were analyzed using a second-order polynomial regression model to construct a response surface model, which elucidated the relationship between the variables and MB removal efficiency. The study found that the char obtained at 800°C exhibited the highest adsorption capacity due to its increased carbonization, expanded surface area, and diverse pore structure. Analysis of Variance (ANOVA) confirmed the significance of the quadratic model, with remarkable agreement between predicted and experimental outcomes. Diagnostic plots validated the model's reliability, while 3D contour graphs illustrated the combined effects of variables on MB removal efficiency. Optimization using DoE software identified optimal conditions resulting in a 99% removal efficiency, which closely matched experimental results. Additionally, adsorption isotherms revealed that the Freundlich model best described the adsorption behavior, indicating heterogeneous surface adsorption with multilayer adsorption. This comprehensive study provides valuable insights into the adsorption process of MB dye using latex char, with implications for wastewater treatment and environmental remediation.

A case of disseminated cryptococcosis with abdominal involvement due to Cryptococcus neoformans species complex in a Ragdoll cat and false-negative cryptococcal antigen lateral flow tests due to the postzone phenomenon.

Although cryptococcosis is the most common systemic fungal disease of cats, abdominal involvement is rarely reported. The pathogenesis of cryptococcosis usually involves sinonasal colonisation, followed by tissue invasion and sinonasal infection, with possible subsequent spread to the lungs and/or direct extension into the central nervous system (CNS), for example, via the cribriform plate. Further haematogenous spread can occur to any tissue, including skin and the CNS. This report describes a case of disseminated cryptococcosis due to Cryptococcus neoformans species complex in a 13-year-old cat, the fourth documented Australian feline case with abdominal involvement. The cat presented with a chronic history of upper respiratory disease that progressed to severe lethargy and anorexia. An autopsy revealed striking peritonitis with multifocal abdominal involvement affecting the liver, spleen, adrenal glands, kidneys, pancreas and mesentery. Cryptococcal organisms were also observed in organs within the thoracic cavity, sinonasal tissues and the CNS. Testing of abdominal fluid and serum for cryptococcal antigen using a commercially available lateral flow assay using neat fluid specimen initially tested false-negative. However, after dilution of the sample to 1:64, a positive result was obtained, confirming a postzone phenomenon. Taken together, the collective findings were indicative of widely disseminated cryptococcosis due to Cryptococcus neoformans with atypical involvement of the abdominal cavity.

Updating the Knowledge on the Secretory Machinery of Hops (Humulus lupulus L., Cannabaceae).

Cannabaceae species garner attention in plant research due to their diverse secretory structures and pharmacological potential associated with the production of secondary metabolites. This study aims to update our understanding of the secretory system in Hops (Humulus lupulus L.), an economically important species especially known for its usage in beer production. For that, stems, leaves, roots, and inflorescences were collected and processed for external morphology, anatomical, histochemical, ultrastructural and cytochemical analyses of the secretory sites. Our findings reveal three types of secretory structures comprising the secretory machinery of Hops: laticifer, phenolic idioblasts and glandular trichomes. The laticifer system is articulated, anastomosing and unbranched, traversing all plant organs, except the roots. Phenolic idioblasts are widely dispersed throughout the leaves, roots and floral parts of the species. Glandular trichomes appear as two distinct morphological types: capitate (spherical head) and peltate (radial head) and are found mainly in foliar and floral parts. The often-mixed chemical composition in the secretory sites serves to shield the plant from excessive UVB radiation, elevated temperatures, and damage inflicted by herbivorous animals or pathogenic microorganisms. Besides the exudate from peltate glandular trichomes (lupulin glands), latex and idioblast content are also likely contributors to the pharmacological properties of different Hop varieties, given their extensive presence in the plant body.

Assessment of Knowledge, Attitude, and Practice of Pharmacovigilance and Materiovigilance among Oral Health Practitioners in India.

Aim: This electronic survey was carried out to assess the knowledge, attitude, and practices among the oral health practitioners. Methods: A questionnaire survey was conducted among undergraduates, graduated practitioners, and specialist practitioners. A Google Form that included a specified instruction format, informed consent with a clear description of the purpose of the study, and questions in different categories were sent through Whatsapp and email. Descriptive statistics were used to analyze responses. The association of knowledge and attitude with respect to oral health professionals was analyzed with the Chi-square test. Results: The questionnaire was completed by 570 participants. Thirty percent of participants encountered ADR related to the drugs available in the market and 33.2% of participants encountered adverse reaction related to materials used in practice. ADR should be reported as soon as it is detected, according to this study about 12.1% of participants reported the ADRs, and this reporting is primarily for patient safety. Almost 66.8% of participants perceived that dental products can cause ADR owing to a lack of information about ADR and reporting procedures, or due to fear of legal concerns. Only about 9.5% of the participants had previously attended an ADR workshop. Conclusion: Oral health practitioners have a general understanding of ADR; however, there is substantial evidence of underreporting and a lack of reporting system information. Organizing an orientation program and raising awareness about ADR reporting could help improve spontaneous reporting and better patient care.

Natural rubber latex-based biomaterials for drug delivery and regenerative medicine: Trends and directions.

Natural Rubber Latex (NRL) has shown to be a promising biomaterial for use as a drug delivery system to release various bioactive compounds. It is cost-effective, easy to handle, biocompatible, and exhibits pro-angiogenic and pro-healing properties for both soft and hard tissues. NRL releases compounds following burst and sustained release kinetics, exhibiting first-order release kinetics. Moreover, its pore density can be adjusted for tailored kinetics profiles. In addition, biotechnological applications of NRL in amblyopia, smart mattresses, and neovaginoplasty have demonstrated success. This comprehensive review explores NRL's diverse applications in biotechnology and biomedicine, addressing challenges in translating research into clinical practice. Organized into eight sections, the review emphasizes NRL's potential in wound healing, drug delivery, and metallic nanoparticle synthesis. It also addresses the challenges in enhancing NRL's physical properties and discusses its interactions with the human immune system. Furthermore, examines NRL's potential in creating wearable medical devices and biosensors for neurological disorders. To fully explore NRL's potential in addressing important medical conditions, we emphasize throughout this review the importance of interdisciplinary research and collaboration. In conclusion, this review advances our understanding of NRL's role in biomedical and biotechnological applications, offering insights into its diverse applications and promising opportunities for future development.

A new surface plasmon resonance-based immunoassay for rapid and sensitive quantification of D-dimer in human plasma for thrombus screening.

D-dimer is a protein fragment generated during the fibrin breakdown by plasmin, and it serves as a mature biomarker for diagnosing thrombotic disorders. A novel immunoassay method based on surface plasmon resonance (SPR) has been developed, validated, and successfully applied for the quantification of D-dimer in human plasma with high sensitivity and rapidity. In this methodological study, we investigated the activity and stability of the SPR biosensor, sample pre-processing, washing conditions, intra-day and inter-day precision and accuracy and detection parameters, including a limit of detection of 8.3 ng/mL, a detection range spanning from 31.25 to 4000 ng/mL, and a detection time of 20 min. We compared D-dimer plasma concentration determination results using SPR with a classical latex-enhanced immunoturbidimetric immunoassay in 29 healthy individuals and thrombotic patients, and both methods exhibited consistency. Furthermore, we propose a hypothesis about the relationship between the concentration of D-dimer and its molecular weight. With an increase in the D-dimer concentration in plasma, the D-dimer approaches its simplest form (190 kDa).

Enhancement in antimicrobial efficacy and biodegradation of natural rubber latex through graphene oxide/nickel oxide nanoparticles.

This work aims to fabricate antibacterial natural rubber latex composites by introducing different ratios of graphene oxide (GO) and nickel oxide (NiO) nanoparticles. The nanocomposites were prepared using latex mixing and a two-roll mill process, followed by molding with a heating hydraulic press. Detailed analyses were conducted to evaluate the rheological, chemical, physical, thermal, mechanical, and electrical performance of the composites. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the interaction among different components, while the surface morphology was examined through the field emission scanning electron microscopy (FESEM) technique. The composites with a loading ratio of 1:2 of GO to NiO (optimized concentration) exhibited the highest tensile strength (24.9 MPa) and tear strength (47.4 N/ mm) among all the tested samples. In addition, the composites demonstrated notable antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The thermal stability of the composites was observed up to 315 °C, and their electrical resistivity lies in the insulating range across a temperature span of 25 °C to 50 °C. The research uncovers critical insights into advancing composite materials suitable for diverse applications, featuring inherent antibacterial attributes, robust mechanical properties, resilience to solvent, UV shielding properties, and controlled electrical resistivity capabilities.

Recent progress in surface engineering methods and advanced applications of flexible polymeric foams.

Polymeric foams, also known as three-dimensional (3D) polymeric sponges, are lightweight, flexible, compressible, and possess a high surface area compared with other bulk polymers. These sponges have traditionally been used for mattresses or seat cushions in homes, offices, aircraft, automobiles, and trains, and to insulate against heat, electricity, and noise. Recently, the demand for modern materials has expanded the application of polymeric foams to various high-value technologies, including in areas that need high flame retardancy, flame sensors, oil/water separation, metal adsorption, solar steam generation, piezoresistivity, electromagnetic interference shielding, thermal energy storage, catalysis, supercapacitors, batteries, and triboelectric energy harvesting. Proper modification of foams is a prerequisite for their use in high-value applications. Several new strategies for the surface coating of 3D porous foams and novel emerging applications have been recently developed. Therefore, in this review, current advances in the field of surface coating and the application of 3D polymeric foams are discussed. A brief background on 3D polymeric foams, including the unique properties and benefits of polymeric sponges and their routes of synthesis, is presented. Different coating strategies for polymeric sponges are discussed, and their advantages and drawbacks are highlighted. Different advanced applications of polymeric sponges, in conjunction with specific and detailed examples of the above-mentioned applications, are also described. Finally, challenges and potential applications related to the coating of polymeric foams are discussed. We envisage that this review will be useful to facilitate further research, promote continued efforts on the advanced applications mentioned above, and provide new stimuli for the design of novel polymeric sponges for future modern applications.

A Study on the Properties of Composite Modified Mortar with Styrene-Butadiene Rubber Latex and Silica Fume.

To solve the problem of the poor abrasion resistance of concrete pavement surface mortar, this study substituted cement with equal amounts of styrene-butadiene rubber (SBR) latex and silica fume (SF) to investigate the effects of organic/inorganic material composite modification on the fluidity, drying shrinkage, mechanical properties, and abrasion resistance of cement mortar. Also in this study, the microstructure, product, and pore structure characteristics of the composite modified cement mortar were investigated using scanning electron microscope (SEM), X-Ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and the Brunauer-Emmett-Teller (BET) method. This research found that the sole substitution of SF negatively impacted the mortar's fluidity and drying shrinkage yet enhanced its mechanical strength and abrasion resistance; the incorporation of SBR latex improved fluidity, reduced shrinkage, and increased flexural strength but adversely affected the compressive strength of the mortar. Additionally, the enhancement of the mortar's abrasion resistance with SBR latex was significantly greater than that with SF. When SBR latex and SF were used together as substitutes, the latex struggled to offset the negative impact of SF on mortar fluidity but effectively reduced shrinkage; SF compensated for the detrimental effect of the latex on compressive strength. Moreover, the primary role in enhancing the mortar's abrasion resistance was played by the latex. Microscopic tests showed that SBR latex and SF could increase the content of calcium silicate hydrate (C-S-H) gel, inhibit the formation of ettringite (AFt) and reduce carbonation, refine the pore size of cement mortar, and effectively improve the microstructure of mortar.

Genome-Wide Characterization and Expression Analyses of Major Latex Protein Gene Family in Populus simonii × P. nigra.

Major latex proteins, or MLPs, are crucial to plants' capacity to grow, develop, and endure biotic and abiotic stresses. The MLP gene family has been found in numerous plants, but little is known about its role in Populus simonii × P. nigra. This study discovered and assessed 43 PtMLP genes that were unevenly dispersed throughout 12 chromosomes in terms of their physicochemical characteristics, gene structure, conserved motifs, and protein localization. Based on their phylogeny and protein structural characteristics, three separate subclasses of PtMLP family were identified. Segmental and tandem duplication were found to be essential variables in the expansion of the PtMLP genes. The involvement of the PtMLP genes in growth and development, as well as in the responses to different hormones and stresses, was demonstrated by cis-regulatory element prediction. The PtMLP genes showed varying expression patterns in various tissues and under different conditions (cold, salt, and drought stress), as demonstrated in RNA-Seq databases, suggesting that PsnMLP may have different functions. Following the further investigation of the genes demonstrating notable variations in expression before and after the application of three stresses, PsnMLP5 was identified as a candidate gene. Subsequent studies revealed that PsnMLP5 could be induced by ABA treatment. This study paves the way for further investigations into the MLP genes' functional mechanisms in response to abiotic stressors, as well as the ways in which they can be utilized in poplar breeding for improved stress tolerance.

Agreement and internal quality assurance of the Neubauer hemocytometer and Makler chamber for human sperm concentration determination.

OBJECTIVE: The Neubauer hemocytometer, as well as the Makler chamber, are devices commonly used in andrology laboratories. The present study aimed to verify if both methods yield comparable results, and whether they can be used interchangeably to determine sperm concentration. METHODS: Sperm and latex beads concentration measurements were performed with the Neubauer hemocytometer and the Makler chamber. Fixed and proportional biases were estimated, and the method agreement was determined by assessing sperm concentration results with the Bland and Altman plot. The Coefficient of Variation (CV) and relative bias were calculated as an index of precision and accuracy, respectively, by measuring latex beads target concentrations in both chambers. RESULTS: The Makler chamber systematically overestimated the Neubauer hemocytometer concentration measurements by a mean of -7.99%, with limits of agreement (LOA) between -41% to 25.61% (p<0.001). The fixed bias was found for concentration values inferior to 40 x 106/ml range (p<0.001), but not higher concentration results (p>0.05). Measurements with the Neubauer hemocytometer showed the greatest consistency in the study with the CV ranging from 3.01% to 6.67%; while the CV with the Makler chamber ranged from 8.46% to 25.64%. The relative bias for the Neubauer hemocytometer determinations varied from 0.12% to 8.40%, while for the Makler chamber varied from 7.6% to an overestimation of 38.0%. CONCLUSIONS: Measurements made with the Makler chamber demonstrated more variability and a higher degree of overestimation. The Makler chamber is a poor substitute to the Neubauer hemocytometer for evaluation of oligozoospermic samples, although both chambers render similar results for highly concentrated samples.

Latex vascular injection as method for enhanced neurosurgical training and skills.

Background: Tridimensional medical knowledge of human anatomy is a key step in the undergraduate and postgraduate medical education, especially in surgical fields. Training simulation before real surgical procedures is necessary to develop clinical competences and to minimize surgical complications. Methods: Latex injection of vascular system in brain and in head-neck segment is made after washing out of the vascular system and fixation of the specimen before and after latex injection. Results: Using this latex injection technique, the vascular system of 90% of brains and 80% of head-neck segments are well-perfused. Latex-injected vessels maintain real appearance compared to silicone, and more flexible vessels compared to resins. Besides, latex makes possible a better perfusion of small vessels. Conclusions: Latex vascular injection technique of the brain and head-neck segment is a simulation model for neurosurgical training based on real experiencing to improve surgical skills and surgical results.

Biobased Interpenetrating Polymer Network Membranes for Sustainable Molecular Sieving.

There is an urgent need for sustainable alternatives to fossil-based polymer materials. Through nanodomain engineering, we developed, without using toxic cross-linking agents, interpenetrating biopolymer network membranes from natural compounds that have opposing polarity in water. Agarose and natural rubber latex were consecutively self-assembled and self-cross-linked to form patchlike nanodomains. Both nano-Fourier transform infrared (nano-FTIR) spectroscopy and computational methods revealed the biopolymers' molecular-level entanglement. The membranes exhibited excellent solvent resistance and offered tunable molecular sieving. We demonstrated control over separation performance in the range of 227-623 g mol-1 via two methodologies: adjusting the molecular composition of the membranes and activating them in water. A carcinogenic impurity at a concentration of 5 ppm, which corresponds to the threshold of toxicological concern, was successfully purged at a negligible 0.56% pharmaceutical loss. The biodegradable nature of the membranes enables an environmentally friendly end-of-life phase; therefore, the membranes have a sustainable lifecycle from cradle to grave.

Development of biodegradable packaging films from carboxymethyl cellulose and oxidised natural rubber latex.

The present study investigates the biopolymer packaging film developed from carboxymethyl cellulose (CMC) with varying concentrations of natural rubber latex (NR) and oxidised natural rubber latex (ONR) using the solvent casting method. The physicochemical properties of the CMC/NR and CMC/ONR film samples were characterised using FTIR, TG/DTA, DSC, SEM, and XRD analysis. The increased concentration of NR and ONR helped to enhance mechanical characteristics, superior UV resistance, enhanced resistance to oxygen and water vapour penetration, improved dimensional stability, and a reduction in the moisture retention ability of the film samples. The CMC sample film, incorporated with 1.5 g ONR, was found to have more than a 100 % increase in the tensile strength. The tensile value increased from 21.56 MPa to 48.36 MPa, with the highest young modulus of 0.73 GPa and elastic stability of 7.14 %. The incorporation of NR and ONR significantly reduced the super water absorbency nature of the CMC film, and the moisture content values reduced from 21.6 % to ≅ 0.15 % for ONR-incorporated film. Additionally, the CMC/NR and CMC/ONR films exhibited high optical transparency values and were found to be fast biodegradable, substantiating their potential use in various packaging applications. Application of these materials in perishable fruit packaging has shown significant enhancement in shelf life, highlighting their practical efficiency and potential for sustainable packaging solutions.

Assessing the impact of the COVID-19 pandemic on latex glove usage and latex allergy complaints among nurses: A descriptive study.

BACKGROUND: The coronavirus 2019 (COVID-19) pandemic has led to a significant increase in the use of latex gloves among nurses. However, concerns about the rise in latex allergies and related complaints due to this increase remain uncertain.OBJECTIVE: This study aims to assess the rates of latex glove usage and allergy-related complaints among nurses working in hospitals during the COVID-19 pandemic. METHODS: Between May 15 and June 15, 2021, ethical approvals were obtained for a cross-sectional study involving 448 volunteer nurses. Descriptive statistics were used to represent categorical values as counts (n) and percentages (%), while continuous values were represented as mean±standard deviation. The normal distribution of the data was assessed using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Comparative analyses were conducted using paired sample t-test, Pearson's chi-squared (x2) test, McNemar's chi-squared (x2) test, and Spearman correlation analysis. RESULTS: Before the pandemic, the average number of invasive procedures was 45.13±26.48, whereas during the pandemic, this rate increased to 50.23±29.14. The average glove usage duration went from 7.69±3.13 hours to 14.73±3.68 hours during the pandemic. Among nurses, the rate of allergic symptoms, which was previously at 31.5%, rose to 33.3% during the pandemic.CONCLUSION: This study revealed a significant increase in daily invasive procedures and the use of latex gloves among nurses during the pandemic period. Simultaneously, the frequency of allergic symptoms also rose. These findings underscore the importance of awareness and preventive measures, particularly regarding latex allergies, in the healthcare field.

Rapid formation of carbon nanotubes-natural rubber films cured with glutaraldehyde for reducing percolation threshold concentration.

Carbon nanotubes (CNTs) filled natural rubber (NR) composites with various CNT contents at 0, 1, 2, 3, 4 and 5 phr were prepared by latex mixing method using glutaraldehyde as curing agent. This work aims to improve the electrical and mechanical properties of CNT filled NR vulcanizates. The CNT dispersion of NR composites was clarified using dispersion grader, optical microscopy and scanning electron microscopy. The electrical properties of NR composites in the existing of CNT networks were studied by following the well-known percolation theory. It was observed that the NR composites exhibited low percolation threshold at 0.98 phr of CNT. Moreover, a three-dimensional network formation of CNT in the NR composites was observed and it is indicated by the t-value of 1.67. The mechanical properties of NR composites in terms of modulus, tensile strength and hardness properties were increased upon the addition of CNT to the optimum mechanical properties at 1 phr of CNT. Therefore, the present work is found the novelty of the study that the conductive rubber latex film can be produced using GA as low-temperature curing agent which enhanced good electrical properties. Moreover, this work is found to be beneficial in case of conductive rubber latex film that requires high modulus at low strain. The additional advantage of this system is the curing process occurs at low-temperature using GA and it can be easily processed.

Extraction process and characterization of Taraxacum kok-saghyz (TKS) latex.

Taraxacum kok-saghyz (TKS) latex is a natural latex produced from its root, and its extraction optimization process is mainly studied in the present paper. The composition of fresh roots of TKS was quantitatively analyzed, and the results showed that the moisture content of the fresh root was approximately 70 %, and the rubber content averaged to 6 % (dry weight ratio). An optimal process route for extracting the TKS latex was finally determined, making the extraction efficiency reach about 80 %, and a new latex extraction process was established and optimized and named "the process of Buffer Extraction TKS Latex (BETL)". Hevea latex, extracted TKS latex and TKS latex collected directly from the broken roots were compared for study. The results showed that, like Hevea latex, the appearance of TKS latex was milky white; and after centrifugation, both showed four layers from top to bottom: rubber particles, Frey-Wyssling particles, C-serum and lutoids. The results of the composition analysis showed that the concentration of TKS latex ranged from 54.54 % to 68.25 %, which is close to that of concentrated Hevea latex; the moisture content of TKS latex was between 31.75 % and 45.46 %. The protein content of TKS latex was 13.51 mg/mL, which was lower than that of Hevea latex at the same rubber hydrocarbon concentration. The molecular structures and properties of Hevea latex, the extracted TKS latex, and the collected TKS latex were characterized by FTIR, 13C NMR, GPC, TG, SEM and LPSA, and the results showed that the main components and structure of the three latexes were similar, which are all cis-1,4-polyisoprene, and include the proteins and lipids. The distributions molecular weights of the three latexes all showed a bimodal distribution, but the molecular weight of the latex collected from TKS was lower, which indicates the larger molecules were difficult to flow outside the root automatically. The Hevea latex and TKS latex rubber particles were both core-shell structure and the size distribution were bimodal, which was consistent with the GPC analysis results.

Late-instar monarch caterpillars sabotage milkweed to acquire toxins, not to disarm plant defence.

Sabotaging milkweed by monarch caterpillars (Danaus plexippus) is a famous textbook example of disarming plant defence. By severing leaf veins, monarchs are thought to prevent the flow of toxic latex to their feeding site. Here, we show that sabotaging by monarch caterpillars is not only an avoidance strategy. While young caterpillars appear to avoid latex, late-instar caterpillars actively ingest exuding latex, presumably to increase sequestration of cardenolides used for defence against predators. Comparisons with caterpillars of the related but non-sequestering common crow butterfly (Euploea core) revealed three lines of evidence supporting our hypothesis. First, monarch caterpillars sabotage inconsistently and therefore the behaviour is not obligatory to feed on milkweed, whereas sabotaging precedes each feeding event in Euploea caterpillars. Second, monarch caterpillars shift their behaviour from latex avoidance in younger to eager drinking in later stages, whereas Euploea caterpillars consistently avoid latex and spit it out during sabotaging. Third, monarchs reared on detached leaves without latex sequestered more cardenolides when caterpillars imbibed latex offered with a pipette. Thus, we conclude that monarch caterpillars have transformed the ancestral 'sabotage to avoid' strategy into a 'sabotage to consume' strategy, implying a novel behavioural adaptation to increase sequestration of cardenolides for defence.