Comparison between hemodynamic effects of remimazolam and propofol during general anesthesia: a systematic review and meta-analysis.

INTRODUCTION: The need for safe anesthetic agents with minimal side effects has led to the development of remimazolam, a new benzodiazepine designed to be an alternative to the commonly used drug propofol, which has significant hemodynamic effects. This study aims to compare the hemodynamic effects of remimazolam with propofol during general anesthesia. EVIDENCE ACQUISITION: A systematic search was conducted in Embase, Web of Science, Cochrane Library, Scopus, and PubMed databases on 13/02/2023, following the recommendations of Cochrane Handbook and the PRISMA statement. The measure of association used was Risk Ratio (RR) or standardized mean difference, with 95% confidence intervals (CI) and 95% Prediction intervals (PI). An additional search was conducted on 04/09/2023. A Trial Sequential Analysis and a GRADE (Grading of Recommendations Assessment, Development and Evaluation) evidence table were conducted based on the editor's recommendation. EVIDENCE SYNTHESIS: After applying eligibility criteria and removing duplicates, 16 randomized clinical trials comprising 1951 patients were included in the meta-analysis. Significant associations favoring remimazolam over propofol were observed in the following aspects: intraoperative hypotension events (RR=0.47; 95% CI=0.41 to 0.54; 95% PI=0.40 to 0.55); frequency of vasoactive drug administration (RR=0.54; 95% CI=0.46 to 0.64; 95% PI=0.41 to 0.74); intraoperative bradycardia (RR=0.39; 95% CI=0.27 to 0.57; 95% PI=0.26 to 0.66); mean arterial pressure at induction (MD=7.77; 95% CI=6.00 to 9.55; 95% PI=4.39 to 11.15); heart rate at induction (MD=6.40; 95% CI=4.07 to 8.73; 95% PI=0.33 to 12.48); and heart rate at intubation (MD=6.06; 95% CI=2.33 to 9.78; 95% PI=-5.59 to 17.71). CONCLUSIONS: This study provides evidence that remimazolam induces fewer cardiorespiratory depressant effects and has a more favorable side effect profile compared to propofol during general anaesthesia.

Olanzapine during lactation: impact on testicular morphometry and endocrine parameters in adult wistar rats.

Olanzapine (OLZ) is an antipsychotic medication used to treat postpartum psychiatric symptoms. It aimed to evaluate the effects of administering OLZ to lactating rats on testicular parameters of adult Wistar rats. Mothers received 2.5, 5 or 10 mg/kg until weaning. Adult male rats showed decrease in body weight, weight of testes, epididymis, prostate, seminal gland and gonadosomatic index when higher doses of OLZ were administered. Testicular volumetric parameters, as well as the length of seminiferous tubules, were also reduced in animals treated with the highest doses of OLZ. The diameter of the seminiferous tubules and the height of the seminiferous epithelium were reduced. There was also a relevant decrease in the population of Sertoli cells and a relevant reduction in the volume of individual Leydig cells. Histopathological analysis of the testes showed lesions compatible with testicular degeneration in rats treated with the highest dose of OLZ. There was a significant reduction in plasma testosterone levels in all treatments. It is noted, therefore, that the adverse impact on the testes of the highest doses of the drug during the neonatal period persisted into adulthood, with the dose of 2.5 mg/kg of OLZ proving to be safer than the others.

Composite Sling: A Strategy for Enhancing Inferolateral Support in Mastopexy with Implant.

Augmentation mastopexy has attracted the attention of numerous authors seeking to improve surgical outcomes and ensure breast implant stability. The utilization of the dual plane technique with a lateral sling, pioneered by Ono and Karner, has demonstrated effectiveness in providing long-term implant support. However, challenges arise in cases of anatomical variations, such as a short pectoralis major (PM) muscle or chest, necessitating alternative approaches like the composite sling. This study presents a technique designed to elongate and broaden the lateral sling to enhance implant support. The composite sling incorporates components from the abdominal part of the PM muscle, the aponeurotic/muscular part of the external oblique muscle, and the cranial part of the rectus abdominis. Procedures were performed on 29 patients using the composite sling technique from July 2022 to October 2023. The follow-up period ranged from 6 to 18 months (average of 11.89 months). The lateral sling approach was successfully extended to cases with a short PM muscle or chest, previously managed using the dual plane technique without inferolateral support. No increase in complications or implant displacements was observed compared with the original lateral sling approach. However, four reoperations addressed issues such as dog ears, scarring, and minor asymmetries. Consistent results were observed throughout the follow-up period, particularly in maintaining upper pole fullness and preventing lower pole ptosis. The composite sling approach provides a viable solution for cases where the original sling technique is impractical. Its implementation could broaden surgical options and optimize results, particularly in cases of unfavorable anatomy.

Diclofenac sodium adsorption on activated carbon: experimental, modeling and bayesian statistics.

The present study modeled the adsorption process of the drug diclofenac sodium on activated charcoal. For this purpose, a mass balance-based model was used considering a fixed bed column. The mass transfer rate in the solid phase was represented by a driving force model proposed in this study, and a gamma exponent with a range of 0 > γ ≤ 2 was assigned to the model. Different isotherms were adopted to represent the equilibrium at the solid/liquid interface: the Langmuir, Freundlich, Sips and Redlich-Peterson isotherms. The modeling was approached from the perspective of Bayesian statistics, and the Markov chain Monte Carlo method was used for parameter estimation. Model validation was performed with experimental data obtained under different operating conditions of initial concentration ($C_{0.

Photoredox C(2)-Arylation of Indole- and Tryptophan-Containing Biomolecules.

We introduce a novel and straightforward methodology for photoredox arylation of an indole scaffold using aryldiazonium salts under mild and metal-free conditions. Our approach enables the regioselective and chemoselective introduction of several aryl groups to the C(2) position of indoles and tryptophan, even in competition with other amino acids. This approach extends to the late-stage functionalization of peptides and lysozyme, heralding the unprecedented arylation of tryptophan residues in wild-type proteins and offering broad utility in chemical biology.

Coding, Decoding and Retrieving a Message Using DNA: An Experience from a Brazilian Center Research on DNA Data Storage.

DNA data storage based on synthetic oligonucleotides is a major attraction due to the possibility of storage over long periods. Nowadays, the quantity of data generated has been growing exponentially, and the storage capacity needs to keep pace with the growth caused by new technologies and globalization. Since DNA can hold a large amount of information with a high density and remains stable for hundreds of years, this technology offers a solution for current long-term data centers by reducing energy consumption and physical storage space. Currently, research institutes, technology companies, and universities are making significant efforts to meet the growing need for data storage. DNA data storage is a promising field, especially with the advancement of sequencing techniques and equipment, which now make it possible to read genomes (i.e., to retrieve the information) and process this data easily. To overcome the challenges associated with developing new technologies for DNA data storage, a message encoding and decoding exercise was conducted at a Brazilian research center. The exercise performed consisted of synthesizing oligonucleotides by the phosphoramidite route. An encoded message, using a coding scheme that adheres to DNA sequence constraints, was synthesized. After synthesis, the oligonucleotide was sequenced and decoded, and the information was fully recovered.

Taxonomic study of Hymenochaetaceae species (Agaricomycetes, Basidiomycota) in the municipalities of Tomé-Açu and Bujaru, Pará, Brazil.

The family Hymenochaetaceae includes a diversity of 893 species described around the world. Its representatives are known by their usually rusty colored basidiomes with a poroid hymenial surface, hydnoid or smooth, woody consistency, and wide morphological variation regarding the arrangement on the substrate. They behave as saprophytic, parasitic, ectomycorrhizal and play a fundamental role in the decomposition of wood in forest ecosystems. In the Brazilian Amazonia region, approximately 40 species of Hymenochaetaceae are currently recorded. The main goal of this study was to increase the knowledge on Hymenochaetaceae from the Brazilian Amazonia. Collections were carried out between October 2021 and April 2022 in the state of Pará, municipalities of Tomé-Açu and Bujaru, to expanding the knowledge of this fungal family to the Brazilian Amazonia. A total of 15 specimens were identified, distributed in seven genera and 12 species. Four species are new records for the state of Pará (Fomitiporia apiahyna, Phellinus neocallimorphus, Phellinus sancti-georgii, and Sclerotus extensus) and two of them are new records for the Brazilian Amazonia (P. neocallimorphus and P. sancti-georgii). Our findings contribute to taxonomic knowledge of this family in the Brazilian Amazonia and reduce the information gaps about the diversity of species.

Treatment using vanillin-derived synthetic molecules incorporated into polymeric micelles is effective against infection caused by Leishmania amazonensis species.

Treatment against leishmaniasis presents problems, mainly due to the toxicity of the drugs, high cost, and the emergence of resistant strains. A previous study showed that two vanillin-derived synthetic molecules, 3s [4-(2-hydroxy-3-(4-octyl-1H-1,2,3-triazol-1-yl)propoxy)-3-methoxybenzaldehyde] and 3t [4-(3-(4-decyl-1H-1,2,3-triazol-1-yl)-2-hydroxypropoxy)-3-methoxybenzaldehyde], presented antileishmanial activity against Leishmania infantum, L. amazonensis, and L. braziliensis species. In the present work, 3s and 3t were evaluated to treat L. amazonensis-infected mice. Molecules were used pure or incorporated into Poloxamer 407-based micelles. In addition, amphotericin B (AmpB) and its liposomal formulation, Ambisome®, were used as control. Animals received the treatment and, one and 30 days after, they were euthanized to evaluate immunological, parasitological, and biochemical parameters. Results showed that the micellar compositions (3s/Mic and 3t/Mic) induced significant reductions in the lesion mean diameter and parasite load in the infected tissue and distinct organs, as well as a specific and significant antileishmanial Th1-type immune response, which was based on significantly higher levels of IFN-γ, IL-12, nitrite, and IgG2a isotype antibodies. Drug controls showed also antileishmanial action; although 3s/Mic and 3t/Mic have presented better and more significant parasitological and immunological data, which were based on significantly higher IFN-γ production and lower parasite burden in treated animals. In addition, significantly lower levels of urea, creatinine, alanine transaminase, and aspartate transaminase were found in mice treated with 3s/Mic and 3t/Mic, when compared to the others. In conclusion, results suggest that 3s/Mic and 3t/Mic could be considered as therapeutic candidates to treat against L. amazonensis infection.

Exercise-induced potentiation of the acute hypoxic ventilatory response: Neural mechanisms and implications for cerebral blood flow.

A given dose of hypoxia causes a greater increase in pulmonary ventilation during physical exercise than during rest, representing an exercise-induced potentiation of the acute hypoxic ventilatory response (HVR). This phenomenon occurs independently from hypoxic blood entering the contracting skeletal muscle circulation or metabolic byproducts leaving skeletal muscles, supporting the contention that neural mechanisms per se can mediate the HVR when humoral mechanisms are not at play. However, multiple neural mechanisms might be interacting intricately. First, we discuss the neural mechanisms involved in the ventilatory response to hypoxic exercise and their potential interactions. Current evidence does not support an interaction between the carotid chemoreflex and central command. In contrast, findings from some studies support synergistic interactions between the carotid chemoreflex and the muscle mechano- and metaboreflexes. Second, we propose hypotheses about potential mechanisms underlying neural interactions, including spatial and temporal summation of afferent signals into the medulla, short-term potentiation and sympathetically induced activation of the carotid chemoreceptors. Lastly, we ponder how exercise-induced potentiation of the HVR results in hyperventilation-induced hypocapnia, which influences cerebral blood flow regulation, with multifaceted potential consequences, including deleterious (increased central fatigue and impaired cognitive performance), inert (unchanged exercise) and beneficial effects (protection against excessive cerebral perfusion).

New synthetic molecules incorporated into polymeric micelles used for treatment against visceral leishmaniasis.

Treatment against visceral leishmaniasis (VL) presents problems, mainly related to drug toxicity, high cost and/or by emergence of resistant strains. In the present study, two vanillin synthetic derivatives, 3 s [4-(2-hydroxy-3-(4-octyl-1H-1,2,3-triazol-1-yl)propoxy)-3-methoxybenzaldehyde] and 3 t [4-(3-(4-decyl-1H-1,2,3-triazol-1-yl)-2-hydroxypropoxy)-3-methoxybenzaldehyde], were evaluated as therapeutic candidates in a murine model against Leishmania infantum infection. Molecules were used pure (3 s and 3 t) or incorporated into Poloxamer 407-based micelles (3 s/M and 3 t/M) in the infected animals, which also received amphotericin B (AmpB) or Ambisome® as control. Results showed that 3 s/M and 3 t/M compositions induced a Th1-type immune response in treated animals, with higher levels of IFN-γ, IL-2, TNF-α, IL-12, nitrite, and IgG2a antibodies. Animals presented also low toxicity and significant reductions in the parasite load in their spleens, livers, bone marrows and draining lymph nodes, as compared as control groups mice, with the evaluations performed one and 30 days after the application of the therapeutics. In conclusion, preliminary data suggest that 3 s/M and 3 t/M could be considered for future studies as therapeutic agents against VL.

Diversity and prevalence of zoonotic infections at the animal-human interface of primate trafficking in Peru.

Wildlife trafficking creates favorable scenarios for intra- and inter-specific interactions that can lead to parasite spread and disease emergence. Among the fauna affected by this activity, primates are relevant due to their potential to acquire and share zoonoses - infections caused by parasites that can spread between humans and other animals. Though it is known that most primate parasites can affect multiple hosts and that many are zoonotic, comparative studies across different contexts for animal-human interactions are scarce. We conducted a multi-parasite screening targeting the detection of zoonotic infections in wild-caught monkeys in nine Peruvian cities across three contexts: captivity (zoos and rescue centers, n = 187); pet (households, n = 69); and trade (trafficked or recently confiscated, n = 132). We detected 32 parasite taxa including mycobacteria, simian foamyvirus, bacteria, helminths, and protozoa. Monkeys in the trade context had the highest prevalence of hemoparasites (including Plasmodium malariae/brasilianum, Trypanosoma cruzi, and microfilaria) and enteric helminths and protozoa were less common in pet monkeys. However, parasite communities showed overall low variation between the three contexts. Parasite richness (PR) was best explained by host genus and the city where the animal was sampled. Squirrel (genus Saimiri) and wooly (genus Lagothrix) monkeys had the highest PR, which was ~2.2 times the PR found in tufted capuchins (genus Sapajus) and tamarins (genus Saguinus/Leontocebus) in a multivariable model adjusted for context, sex, and age. Our findings illustrate that the threats of wildlife trafficking to One Health encompass exposure to multiple zoonotic parasites well-known to cause disease in humans, monkeys, and other species. We demonstrate these threats continue beyond the markets where wildlife is initially sold; monkeys trafficked for the pet market remain a reservoir for and contribute to the translocation of zoonotic parasites to households and other captive facilities where contact with humans is frequent. Our results have practical applications for the healthcare of rescued monkeys and call for urgent action against wildlife trafficking and ownership of monkeys as pets.

Safe Augmentation Mastopexy: Review of 500 Consecutive Cases Using a Vertical Approach and Muscular Sling.

Background: Augmentation mastopexy remains a challenging surgery and has been frequently associated with suboptimal outcomes and remarkable reoperation rates, and one of the greatest challenges in mastopexy surgery is areolar lift, especially when implants are simultaneously used. Through the authors' experience, this study is aimed to show a modification of the vertical approach with greater safety of the areolar pedicle. Methods: The study included all patients who underwent augmentation mastopexy surgery performed by the authors between 2019 and 2022, whether primary or nonprimary, and performed a retrospective chart review of all patients who underwent this procedure. Results: The length of the areolar lift ranged from 0 cm to 14 cm. Among the 17.4% of nonprimary mastopexies, the longest areolar lift was 11 cm. No cases of nipple-areola complex ischemia/necrosis were observed. With this technique, there were 6.2% complications (n = 31), none of which were considered serious. Conclusions: This surgical sequence is a safe option for areolar lift in augmentation mastopexy. The vertical approach also has the advantage of producing considerably shorter horizontal scars. It is also reproducible, keeping the implant stable, which results in consistent long-term results.

Altered locomotor muscle metaboreflex control of ventilation in patients with COPD.

We investigated the locomotor muscle metaboreflex control of ventilation, circulation, and dyspnea in patients with chronic obstructive pulmonary disease (COPD). Ten patients [forced expiratory volume in 1 second (FEV1; means ± SD) = 43 ± 17% predicted] and nine age- and sex-matched controls underwent 1) cycling exercise followed by postexercise circulatory occlusion (PECO) to activate the metaboreflex or free circulatory flow to inactivate it, 2) cold pressor test to interpret whether any altered reflex response was specific to the metaboreflex arc, and 3) muscle biopsy to explore the metaboreflex arc afferent side. We measured airflow, dyspnea, heart rate, arterial pressure, muscle blood flow, and vascular conductance during reflexes activation. In addition, we measured fiber types, glutathione redox balance, and metaboreceptor-related mRNAs in the vastus lateralis. Metaboreflex activation increased ventilation versus free flow in patients (∼15%, P < 0.020) but not in controls (P > 0.450). In contrast, metaboreflex activation did not change dyspnea in patients (P = 1.000) but increased it in controls (∼100%, P < 0.001). Other metaboreflex-induced responses were similar between groups. Cold receptor activation increased ventilation similarly in both groups (P = 0.46). Patients had greater type II skeletal myocyte percentage (14%, P = 0.010), lower glutathione ratio (-34%, P = 0.015), and lower nerve growth factor (NGF) mRNA expression (-60%, P = 0.031) than controls. Therefore, COPD altered the locomotor muscle metaboreflex control of ventilation. It increased type II myocyte percentage and elicited redox imbalance, potentially producing more muscle metaboreceptor stimuli. Moreover, it decreased NGF expression, suggesting a downregulation of metabolically sensitive muscle afferents.NEW & NOTEWORTHY This study's integrative physiology approach provides evidence for a specific alteration in locomotor muscle metaboreflex control of ventilation in patients with COPD. Furthermore, molecular analyses of a skeletal muscle biopsy suggest that the amount of muscle metaboreceptor stimuli derived from type II skeletal myocytes and redox imbalance overcame a downregulation of metabolically sensitive muscle afferents.

Influence of Fractional Inspired Oxygen Tension on Lung Perfusion Distribution, Regional Ventilation, and Lung Volume during Mechanical Ventilation of Supine Healthy Swine.

BACKGROUND: Lower fractional inspired oxygen tension (Fio2) during general anesthesia can reduce lung atelectasis. The objectives are to evaluate the effect of two Fio2 (0.4 and 1) during low positive end-expiratory pressure (PEEP) ventilation over lung perfusion distribution, volume, and regional ventilation. These variables were evaluated at two PEEP levels and unilateral lung atelectasis. METHODS: In this exploratory study, 10 healthy female piglets (32.3 ± 3.4 kg) underwent mechanical ventilation in two atelectasis models: (1) bilateral gravitational atelectasis (n = 6), induced by changes in PEEP and Fio2 in three combinations: high PEEP with low Fio2 (Fio2 = 0.4), zero PEEP (PEEP0) with low Fio2 (Fio2 = 0.4), and PEEP0 with high Fio2 (Fio2 = 1); and (2) unilateral atelectasis (n = 6), induced by left bronchial occlusion, with the left lung aerated (Fio2 = 0.21) and low aerated (Fio2 = 1; n = 5 for this step). Measurements were conducted after 10 min in each step, encompassing assessment of respiratory mechanics, oxygenation, and hemodynamics; lung ventilation and perfusion by electrical impedance tomography; and lung aeration and perfusion by computed tomography. RESULTS: During bilateral gravitational atelectasis, PEEP reduction increased atelectasis in dorsal regions, decreased respiratory compliance, and distributed lung ventilation to ventral regions with a parallel shift of perfusion to the same areas. With PEEP0, there were no differences between low and high Fio2 in respiratory compliance (23.9 ± 6.5 ml/cm H2O vs. 21.9 ± 5.0; P = 0.441), regional ventilation, and regional perfusion, despite higher lung collapse (18.6 ± 7.6% vs. 32.7 ± 14.5%; P = 0.045) with high Fio2. During unilateral lung atelectasis, the deaerated lung had a lower shunt (19.3 ± 3.6% vs. 25.3 ± 5.5%; P = 0.045) and lower computed tomography perfusion to the left lung (8.8 ± 1.8% vs. 23.8 ± 7.1%; P = 0.007). CONCLUSIONS: PEEP0 with low Fio2, compared with high Fio2, did not produce significant changes in respiratory system compliance, regional lung ventilation, and perfusion despite significantly lower lung collapse. After left bronchial occlusion, the shrinkage of the parenchyma with Fio2 = 1 enhanced hypoxic pulmonary vasoconstriction, reducing intrapulmonary shunt and perfusion of the nonventilated areas.

Cost-Utility Model of Nirmatrelvir/Ritonavir in Brazil: Analysis of a Vaccinated Population.

OBJECTIVES: The aim of this study is to conduct a cost-utility analysis of the use of the antiviral nirmatrelvir/ritonavir, applied to a vaccinated Brazilian population against COVID-19, from the perspective of the Brazilian Public Health System (SUS). METHODS: A microsimulation model was created with individual-level data and daily cycles, with a 1-year time horizon, to compare the current scenario of standard care with a scenario in which nirmatrelvir/ritonavir is offered to the population. Adults of any age group that received ≥2 doses of the COVID-19 vaccine formed the investigated population. Direct medical costs of the outpatients and inpatients admitted to the ward or intensive care unit were included. The effectiveness of the model was measured in quality-adjusted life-years (QALYs). RESULTS: In all simulations, the use of nirmatrelvir/ritonavir resulted in incremental costs per patient of US dollar (USD)245.86 and incremental effectiveness of 0.009 QALY, over a year. The incremental cost-utility ratio was USD27 220.70/QALY. The relative risk of the vaccinated population was the factor that affected the outcome most, according to the univariate sensitivity analysis. The probabilistic sensitivity analysis resulted in 100% of the simulations being more costly and effective, but that only 4% of them were below the established cost-effectiveness threshold of USD24 000.00/QALY. In the scenario considering only the population over 60 years old and immunosuppressed (of any age), the incremental cost-utility ratio was USD7589.37/QALY. CONCLUSIONS: The use of nirmatrelvir/ritonavir in the treatment of COVID-19 in a vaccinated population was cost-effective only for immunosuppressed individuals and people over 60 years of age.

Moderate similarity leads to empathic concern, but high similarity can also induce personal distress towards others' pain.

Empathic concern and personal distress are common vicarious emotional responses that arise when witnessing someone else's pain. However, the influence of perceived similarity on these responses remains unclear. In this study, we examined how perceived similarity with an injured target impacts vicarious emotional responses. A total of 87 participants watched a video of an athlete in pain preceded by a clip describing the athlete's trajectory, which indicated either high, moderate, or low similarity to the participants. Emotional self-reports, facial expressions, gaze behavior, and pupil diameter were measured as indicators of the participants' emotional responses. Participants in the moderate- and high-similarity groups exhibited greater empathic concern, as evidenced by their display of more sadness compared with those in the low-similarity group. Furthermore, those in the moderate-similarity group exhibited less avoidance by displaying reduced disgust, indicating lower personal distress compared with those in the low-similarity condition. Nevertheless, the high-similarity group displayed just as much disgust as the low-similarity group. These findings suggest that perceived similarity enhances empathic concern to others' suffering, but that high similarity can also lead to personal distress. Future studies on empathy should explore distinct vicarious states using multimodal measurements to further advance our understanding of these processes.

Effects of twelve weeks of dance Exergames on the quality-of-life variables of elderly Brazilian women enrolled in a community program.

BACKGROUND AND PURPOSE: Exercise-based interventions can be a safe alternative to improve and maintain physical and mental health during the aging process. The aim of the present study was to evaluate the effects of a 12-week training program with Dance Exergames on the mood and functional fitness profile of elderly women. METHODS: The sample (n = 22) was divided into Exergames (EG, n = 9, 70.6 ± 1.6 years) and Control Groups (CG, n = 13, 73.6 ± 2.2 years). Evaluations were carried out before and after the interventions. Each participant played, in pairs, the electronic game Dance Central 3, with the XBOX 360 Kinect console (Slim, Microsoft, USA). The EG trained for 12 weeks (24 sessions), with two weekly sessions of 50 min and the CG performed manual activities workshops. RESULTS: In functional fitness, both exercise training with exergame (EG) and the intervention model for the CG did not produce significant effects regarding interaction (group*time). Mood state presented significant effect of time intervention regarding tension (p = <0.001), depression (p = 0.001), anger (p = 0.030), fatigue (p = 0.001), and mental confusion (p = 0.004). CONCLUSION: Twelve weeks of training with a dance exergame (for, EG) and manual activities (for, CG) is enough to promote improvements in the mood state of healthy elderly women. This is an interesting result, as it shows that social interaction is as important a component as improving functional capacity.

κ-Carrageenan/poly(vinyl alcohol) functionalized films with gallic acid and stabilized with metallic ions.

Given the environmental issues caused by the extensive use of conventional petroleum-based packaging, this work proposes functional films based on commercial κ-carrageenan (κc), poly(vinyl alcohol) (PVA), and gallic acid (GA) prepared by the "casting" method. Metallic ions in the κc composition stabilized the films, supporting processability and suitable mechanical properties. However, the incorporated GA amount (6.25 and 10 wt%) in the films created from an aqueous κc solution at 3.0 % wt/v (κc3) prevented crystalline domains in the resulting materials. The κc3/GA6.25 and κc3/GA10 films had less tensile strength (8.50 ± 0.61 and 10.28 ± 0.65 MPa) and high elongation at break (2.36 ± 0.16 and 1.19 ± 0.17 %) compared to the other samples, respectively. Low κc contents (κc2.5/GA6.25 and κc2.5/GA10) promoted stiff films and less permeability to water vapor (5.36 ± 0.51 and 3.76 ± 0.02 [×10-12 g(Pa × m × s)-1], respectively. The κc/GA weight ratio also influenced the film wettability, indicating water contact angles (WCAs) between 55 and 74°. The surface wettability implies a low oil permeability and high water swelling capacity of up to 1600 %. The κc/GA also played an essential role in the film's antimicrobial action against Staphylococcus aureus and Escherichia coli. Thus, the κc3/GA10 film showed suitable physical, chemical, and biological properties, having the potential to be applied as food coatings.

Assessment of Wood Bio-Concrete Properties Modified with Silane-Siloxane.

Bio-based materials, such as wood bio-concrete (WBC), hold promise in reducing energy consumption and carbon footprint of the construction industry. However, the durability of these materials is not well understood and can be negatively affected by the high water absorption capacity of wood bio-aggregates. In the field of cement composites, for example, silane-siloxane-based water repellent has been used to protect such materials from natural environmental attack. Nevertheless, there is still a limited understanding of various aspects related to this type of treatment, including its performance when applied to the bio-concrete substrate. This research aimed to investigate the influence of silane-siloxane on the rheology and hydration of cementitious paste through isothermal calorimetry and thermogravimetric analysis. Additionally, the impact of silane-siloxane on the physical and mechanical properties of WBCs was examined by conducting tests at fresh state (flow table and entrained air content) and hardened state (compressive strength and capillary water absorption). The composites were produced with a volumetric fraction of 45% of wood shavings while the cement matrix consisted of a combination of cement, rice husk ash, and fly ash. Silane-siloxane was applied in three ways: as coating, incorporated as an admixture, and in a combination of both methods. The results indicated that by incorporating silane in the cementitious pastethe viscosity increased by 40% and the hydration was delayed by approximately 6 h when compared to the reference. In addition, silane improved the compressive strength of WBCs by 24% when incorporated into the mixture, expressively reduced the water sorptivity of WBCs (93%), and was more effective if used as coating.