Essential oils have been studied to replace synthetic chemical preservatives, among these oils, the thyme essential oil stands out. However, in addition to promoting microbial control, synthetic ...chemical preservatives impart a characteristic color to inlaid products, a parameter not attained by the application of essential oils. This study aimed to evaluate the effect of the joint addition of thyme essential oil and powdered beet juice to meat sausage, for a partial or total reduction of the addition of nitrates and nitrites. The thyme essential oil showed a high inhibitory action against Staphylococcus aureus and Escherichia coli in the concentration of 9.17 mg/mL, and bactericidal effect in the concentrations of 9.17 mg/mL and 36.68 mg/mL respectively, in all tests applied in vitro. When applied to meat sausages, it showed an inhibitory effect against coagulase-positive Staphylococcus, reducing the microorganism count, and partial inhibition of aerobic mesophilic bacteria. No interference was observed in the multiplication of thermotolerant coliforms in the meat product. When evaluated sensorially, the sausage presented good general acceptability, with acceptance levels above 75%. The combined uses of thyme essential oil and powdered beet juice showed potential viability for use in substitution for nitrates and nitrites in meat sausages.
•Thyme essential oil has antimicrobial activity in vitro against Staphylococcus aureus and Escherichia coli.•Thyme essential oil and powdered beet juice promoted the control of microorganisms in meat sausages.•Meat sausages with thyme essential oil or powdered beet juice have good sensory acceptance.
The colloidal suspensions of aqueous cellulose nanocrystals (CNCs) are known to form liquid crystalline (LC) systems above certain critical concentrations. From an isotropic phase, tactoid formation, ...growth, and sedimentation have been determined as the genesis of a high‐density cholesteric phase, which, after drying, originates solid iridescent films. Herein, the coexistence of a liquid crystal upper phase and an isotropic bottom phase in CNC aqueous suspensions at the isotropic–nematic phase separation is reported. Furthermore, isotropic spindle‐like domains are observed in the low‐density LC phase and high‐density LC phases are also prepared. The CNCs isolated from the low‐ and high‐density LC phases are found to have similar average lengths, diameters, and surface charges. The existence of an LC low‐density phase is explained by the presence of air dissolved in the water present within the CNCs. The air dissolves out when the water solidifies into ice and remains within the CNCs. The self‐adjustment of the cellulose chain conformation enables the entrapment of air within the CNCs and CNC buoyancy in aqueous suspensions.
A new low‐density liquid crystalline (LC) phase in aqueous colloidal suspensions of rod‐like cellulose nanocrystals (CNCs) is demonstrated. This behavior is an indication that the LC phase is an indirect way to reveal CNCs/water interactions. The scale bar in the image is 100 µm.
•Liver transplantation patients faced unique challenges during the pandemic.•Challenges included dependence, fear, and stress.•Coping strategies included establishing a support network and ...reorganizing demands.•Patients demonstrated determination to create strategies to prevent SARS-CoV-2.•This data may inform better preparation by professionals involved in patient care.
We aimed to identify the challenges and strategies experienced by patients undergoing liver transplantation during the COVID-19 pandemic.
This was a descriptive study with a qualitative approach conducted in a large liver transplant hospital in southern Brazil.
The participants included liver transplant patients between the years 2011 and 2022. Data collection was performed using a semi-structured interview. Data analysis comprised approximation of information and calculation of percentages.
A total of 23 patients participated. Challenges identified included an increased dependence on others for daily activities, fear and stress due to the possibility of contamination, and the need for isolation from family and friends. Strategies included adaptation to the daily routine, reorganization of tasks inside and outside the home, formation of a support network, and reduced attendance to consultations and exams.
Evidence of anguish and suffering of patients facing isolation and separation from family members was observed. Still, the study revealed the strength and determination of the patients to create strategies for preventing the SARS-CoV-2 virus and caring for themselves and their families. The study demonstrates the need for support from the health team in the face of such a scenario.
Cellulose Nanocrystals
Rod‐like cellulose nanocrystal aqueous colloidal suspensions can be prepared from eucalyptus kraft pulp. In article number 2108227, Maria Helena Godinho and co‐workers show the ...formation of a liquid crystalline (LC) phase atop an isotropic phase, inverted from the typical high‐density LC phase. The bounciness of the particles is attributed to the presence of air. The behavior observed is an indication that the LC phase is an indirect way to reveal cellulose nanocrystal/water interactions.
The development of new Drug Delivery Systems (DDS) by incorporating microparticles within hydrogels can prolong the release rate of drugs and/or other bioactive agents. In this study, we combined ...gellan gum/alginate microparticles within a thermoresponsive chitosan (Ch) hydrogel with β-Glycerophosphate (β-GP), designing the system to be in the sol state at 21 °C and in the gel state at 37 °C to enable the injectability of the system. The system was in the sol state between 10 °C and 21 °C. Higher concentrations of β-GP (0, 2, 3, 4, 5 w/v%) and microparticles (0, 2 and 5 w/v%) allowed a faster sol-gel transition with higher mechanical strength at 37 °C. However, the sol-gel transition was not instantaneous. The release profile of methylene blue (MB) from the microparticles was significantly affected by their incorporation in Ch/β-GP hydrogels, only allowing the release of 60–70 % of MB for 6 days, while the microparticles alone released all the MB in 48 h. The proposed system did not present cytotoxicity to VERO cell lines as a preliminary assay, with the Ch/β-GP/GG:Alg having >90 % of cellular viability. The proposed Ch/β-GP system proved to have a delaying effect on drug release and biocompatible properties, being a promising future DDS.
ABSTRACT Minimally processed strawberries have high acceptability but a short shelf life. The application of edible coatings with essential oils may be an alternative to preserve these fruits. Our ...objective was to develop, apply and characterize the effect of bioactive edible coatings based on agar or sodium alginate with thyme and/or sweet orange essential oils with antimicrobial properties, mainly against Listeria monocytogenes, for strawberries. The effect of the coatings on the physicochemical, microbiological, and sensory properties that determine the shelf life of strawberries was verified at 1, 8, and 15 days. The effect against Listeria monocytogenes bacteria in strawberries artificially contaminated with this microorganism was also evaluated. Thyme and sweet orange essential oils had thymol and D-limonene, respectively, as main components. Alginate coating with sweet orange and thyme essential oil showed the best results. For Listeria monocytogenes, the coating applied after fruit contamination had an antimicrobial effect.
Cellulose micro/nanomaterials (CMNM), comprising cellulose microfibrils (CMF), nanofibrils (CNF), and nanocrystals (CNC), are being recognized as promising bio-nanomaterials due to their natural and ...renewable source, attractive properties, and potential for applications with industrial and economical value. Thus, it is crucial to investigate their potential toxicity before starting their production at a larger scale. The present study aimed at evaluating the cell internalization and in vitro cytotoxicity and genotoxicity of CMNM as compared to two multi-walled carbon nanotubes (MWCNT), NM-401 and NM-402, in A549 cells. The exposure to all studied NM, with the exception of CNC, resulted in evident cellular uptake, as analyzed by transmission electron microscopy. However, none of the CMNM induced cytotoxic effects, in contrast to the cytotoxicity observed for the MWCNT. Furthermore, no genotoxicity was observed for CNF, CNC, and NM-402 (cytokinesis-block micronucleus assay), while CMF and NM-401 were able to significantly raise micronucleus frequency. Only NM-402 was able to induce ROS formation, although it did not induce micronuclei. Thus, it is unlikely that the observed CMF and NM-401 genotoxicity is mediated by oxidative DNA damage. More studies targeting other genotoxicity endpoints and cellular and molecular events are underway to allow for a more comprehensive safety assessment of these nanocelluloses.
Cellulose micro/nanomaterials (CMNMs) are innovative materials with a wide spectrum of industrial and biomedical applications. Although cellulose has been recognized as a safe material, the unique ...properties of its nanosized forms have raised concerns about their safety for human health. Genotoxicity is an endpoint that must be assessed to ensure that no carcinogenic risks are associated with exposure to nanomaterials. In this study, we evaluated the genotoxicity of two types of cellulose micro/nanofibrils (CMF and CNF) and one sample of cellulose nanocrystals (CNC), obtained from industrial bleached Eucalyptus globulus kraft pulp. For that, we exposed co-cultures of human alveolar epithelial A549 cells and THP-1 monocyte-derived macrophages to a concentration range of each CMNM and used the micronucleus (MN) and comet assays. Our results showed that only the lowest concentrations of the CMF sample were able to induce DNA strand breaks (FPG-comet assay). However, none of the three CMNMs produced significant chromosomal alterations (MN assay). These findings, together with results from previous in vitro studies using monocultures of A549 cells, indicate that the tested CNF and CNC are not genotoxic under the conditions tested, while the CMF display a low genotoxic potential.
In this work, a series of isoxazolyl and tetrazolylcinnamic ester hybrid liquid crystals (HLCs) were synthesised and their mesomorphic behaviour was analysed. Cinnamic acid derivatives were prepared ...by Knoevenagel condensation of malonic acid and arylaldehydes. Five-membered tetrazoles and isoxazoles were prepared by 3 + 2 1,3-dipolar cycloaddition. Tetrazoles were synthesised by sodium azide addition to arylnitrile, while isoxazoles were synthetised by arylnitrile oxide addition to alkenes to form isoxazolines, followed by MnO
2
-oxidation. Tetrazolyltolane compounds were also synthesised and their LC behaviour compared with cinnamic esters. HLCs containing isoxazole rings displayed a large mesophase range with high clearing temperature (T
c
), with predominance of smectic mesophases SmA and SmC. The HLCs decomposed upon heating due to their high clearing temperature (>250°C). HLCs with tetrazole rings showed a narrow nematic mesophase range with enantiotropic or monotropic behaviour.
Prostate development and function are regulated by androgens. Epithelial cell apoptosis in response to androgen deprivation is caspase‐9‐dependent and peaks at Day 3 after castration. However, ...isolated epithelial cells survive in the absence of androgens. Znf142 showed an on‐off expression pattern in intraepithelial CD68‐positive macrophages, with the on‐phase at Day 3 after castration. Rats treated with gadolinium chloride to deplete macrophages showed a significant drop in apoptosis, suggesting a causal relationship between macrophages and epithelial cell apoptosis. Intraepithelial M1‐polarization was also limited to Day 3, and the inducible nitric oxide synthase (iNOS) knockout mice showed significantly less apoptosis than wild‐type controls. The epithelial cells showed focal DNA double‐strand breaks (DSB), 8‐oxoguanine, and protein tyrosine‐nitrosylation, fingerprints of exposure to peroxinitrite. Cultured epithelial cells induced M1‐polarization and showed focal DSB and underwent apoptosis. The same phenomena were reproduced in LNCaP cells cocultured with Raw 264.7 macrophages. In conclusion, the M1
142‐macrophage (named after Znf142) attack causes activation of the intrinsic apoptosis pathway in epithelial cells after castration.
Prostate epithelial cell apoptosis is not cell autonomous. M1‐polarized macrophages cause intense oxidative stress, which in turn activates the intrinsic apoptotic pathway. Soluble factors produced by epithelial cells cultured in the absence of androgens differentiate macrophage precursors into M1, which actively chase the epithelial cells.
