RESUMO
Microbial dissimilatory sulfate reduction (DSR) is a key process in the Earth biogeochemical sulfur cycle. In spite of its importance to the sulfur and carbon cycles, industrial processes, and human health, it is still not clear how reduction of sulfate to sulfide is coupled to energy conservation. A central step in the pathway is the reduction of sulfite by the DsrAB dissimilatory sulfite reductase, which leads to the production of a DsrC-trisulfide. A membrane-bound complex, DsrMKJOP, is present in most organisms that have DsrAB and DsrC, and its involvement in energy conservation has been inferred from sequence analysis, but its precise function was so far not determined. Here, we present studies revealing that the DsrMKJOP complex of the sulfate reducer Archaeoglobus fulgidus works as a menadiol:DsrC-trisulfide oxidoreductase. Our results reveal a close interaction between the DsrC-trisulfide and the DsrMKJOP complex and show that electrons from the quinone pool reduce consecutively the DsrM hemes b, the DsrK noncubane [4Fe-4S]3+/2+ catalytic center, and finally the DsrC-trisulfide with concomitant release of sulfide. These results clarify the role of this widespread respiratory membrane complex and support the suggestion that DsrMKJOP contributes to energy conservation upon reduction of the DsrC-trisulfide in the last step of DSR.
Assuntos
Sulfito de Hidrogênio Redutase , Sulfatos , Humanos , Sulfatos/metabolismo , Anaerobiose , Sulfito de Hidrogênio Redutase/metabolismo , Óxidos de Enxofre , Enxofre/metabolismo , Sulfetos/metabolismo , Respiração , OxirreduçãoRESUMO
Dissimilatory sulfur metabolism was recently shown to be much more widespread among bacteria and archaea than previously believed. One of the key pathways involved is the dsr pathway that is responsible for sulfite reduction in sulfate-, sulfur-, thiosulfate-, and sulfite-reducing organisms, sulfur disproportionators and organosulfonate degraders, or for the production of sulfite in many photo- and chemotrophic sulfur-oxidizing prokaryotes. The key enzyme is DsrAB, the dissimilatory sulfite reductase, but a range of other Dsr proteins is involved, with different gene sets being present in organisms with a reductive or oxidative metabolism. The dsrD gene codes for a small protein of unknown function and has been widely used as a functional marker for reductive or disproportionating sulfur metabolism, although in some cases this has been disputed. Here, we present in vivo and in vitro studies showing that DsrD is a physiological partner of DsrAB and acts as an activator of its sulfite reduction activity. DsrD is expressed in respiratory but not in fermentative conditions and a ΔdsrD deletion strain could be obtained, indicating that its function is not essential. This strain grew less efficiently during sulfate and sulfite reduction. Organisms with the earliest forms of dsrAB lack the dsrD gene, revealing that its activating role arose later in evolution relative to dsrAB.
Assuntos
Sulfito de Hidrogênio Redutase/metabolismo , Enxofre/metabolismo , Regulação Alostérica , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Deleção de Genes , Regulação da Expressão Gênica , Modelos Biológicos , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Enxofre/químicaRESUMO
BACKGROUND: Pediatric patients with chronic kidney disease (CKD) frequently present an inadequate nutritional profile and musculoskeletal impairments. We investigated sarcopenia and its related traits in children and adolescents with CKD. METHODS: A cross-sectional study that enrolled pediatric patients with CKD (≥ 4 and < 18 years old). Physical function was assessed by handgrip strength and the 60-s sit-to-stand (STS-60) tests. Body composition measurement was performed by bioelectrical impedance analysis and anthropometry through mid-upper arm circumference (MUAC). Normative reference values from healthy pediatrics were used for identifying poor physical function and low MUAC. Probable sarcopenia was considered as low handgrip strength, whereas sarcopenia was defined by adding low MUAC. RESULTS: Twenty-two pediatric patients with CKD (11 ± 4 years and 59% boys) were evaluated; eight on peritoneal dialysis (36%), six on hemodialysis (27%), and eight non-dialysis (36%). Regarding sarcopenia traits, we observed low physical function by handgrip strength and STS-60 in 59% and 100% of the patients, respectively, while low MUAC in 77%. Probable sarcopenia was found in 9% and sarcopenia in 50%, but prevalence did not differ among stages. Handgrip strength was strongly associated with MUAC (r = 0.90; p < 0.001); on the other hand, the STS-60 was not significantly associated with any of the body composition variables. CONCLUSION: Among pediatric patients with CKD, the prevalence of sarcopenia and its related traits was high. Nephrology professionals should consider the assessment of sarcopenia in this population, while more evidence is needed to determine its prognostic value. A higher resolution version of the Graphical abstract is available as Supplementary information.
Assuntos
Insuficiência Renal Crônica , Sarcopenia , Masculino , Adolescente , Humanos , Criança , Feminino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Sarcopenia/etiologia , Estudos Transversais , Força da Mão , Antropometria , Insuficiência Renal Crônica/complicações , Força MuscularRESUMO
Genome-scale metabolic models have been recognised as useful tools for better understanding living organisms' metabolism. merlin (https://www.merlin-sysbio.org/) is an open-source and user-friendly resource that hastens the models' reconstruction process, conjugating manual and automatic procedures, while leveraging the user's expertise with a curation-oriented graphical interface. An updated and redesigned version of merlin is herein presented. Since 2015, several features have been implemented in merlin, along with deep changes in the software architecture, operational flow, and graphical interface. The current version (4.0) includes the implementation of novel algorithms and third-party tools for genome functional annotation, draft assembly, model refinement, and curation. Such updates increased the user base, resulting in multiple published works, including genome metabolic (re-)annotations and model reconstructions of multiple (lower and higher) eukaryotes and prokaryotes. merlin version 4.0 is the only tool able to perform template based and de novo draft reconstructions, while achieving competitive performance compared to state-of-the art tools both for well and less-studied organisms.
Assuntos
Genoma , Neurofibromina 2 , Algoritmos , Células Procarióticas , SoftwareRESUMO
BACKGROUND: Physical activity (PA) promotion in healthcare systems is one of the priority areas highlighted by the World Health Organization, which recognizes that progress has been slow largely due to a lack of awareness and investment while requiring a system-based approach. Community pharmacies are one of the health structures that are more easily accessible to populations, thus constituting an ideal venue for developing health promotion activities. This research aimed to describe PA-enabling interventions developed in community pharmacies by pharmacists. METHODS: An electronic search was performed in PubMed, Scopus, Web of Science, Cochrane and reference lists of the different papers until June 2023. Studies were eligible if performed in community pharmacies by pharmacists, focused on interventions aimed at increasing PA levels and if at least one PA-specific outcome was measured at two different time points. RESULTS: We identified 7076 publications in the initial search, plus 31 records identified through backward citation tracking from relevant studies. After an initial screening, 236 were selected for full-text analysis. Of the 29 selected papers, 10 presented a low risk of bias for the measurement of PA levels. PA outcomes were generally self-reported outcomes where the change in terms of the percentage of individuals considered active or who increased PA because of the intervention. CONCLUSION: Several interventions to improve PA through community pharmacies were found although with a high level of heterogeneity and with only few with a low risk of bias. More targeted research that aims to capture PA levels and support the training of healthcare professionals is needed.
Assuntos
Serviços Comunitários de Farmácia , Exercício Físico , Promoção da Saúde , Farmacêuticos , Papel Profissional , Humanos , Promoção da Saúde/métodos , FarmáciasRESUMO
AIM: To compare the effects of Cervical Access Cavity (CervAC) and Traditional Access Cavity (TradAC) on root canal preparation, root canal filling, and fracture resistance in mandibular incisors. METHODOLOGY: Twenty recently extracted and intact mandibular incisors were initially scanned using a micro-CT device. The specimens were anatomically matched to create two groups (n = 10). A wedge-shaped non-carious cervical lesion (NCCL) was created on the buccal aspect of all teeth using a double-faced segmented diamond disc. In group 1, a TradAC was prepared, whilst in group 2, access was created through the simulated NCCL using a round diamond bur 1012. After root canal preparation with Rotate instruments sizes 15/0.04, 20/0.04, and 25/0.04, the teeth were scanned again and evaluated for root canal volume and surface area, static voxels, volume of removed dental tissue, and dentine thickness. After that, the root canals were filled using the single-cone technique, teeth were restored with composite resin, and subsequently rescanned to calculate the volume of filling materials and voids. Then, the restored teeth were subjected to fracture resistance tests using a universal testing machine. Statistical comparisons between groups were performed with the Mann-Whitney test or the Student's t-test, with a statistical significance level of 5%. RESULTS: Statistical comparisons indicated no significant differences between groups in terms of root canal volume, surface area, static voxels, removed root dentine, root canal filling volume, percentage of voids, or fracture resistance load (p > .05). Conversely, teeth prepared with TradAC showed a significantly higher percentage of dental tissue removed from the crown (p = .001) and a greater volume of filling material remnants in the pulp chamber (p < .001) compared to the CervAC group. A significantly lower percentage reduction in dentine thickness was observed only on the mesial aspect of root at Level 1 in TradAC group (p = .008). CONCLUSIONS: CervAC can be considered a viable alternative approach in the presence of NCCL in mandibular incisors.
RESUMO
OBJECTIVE: This rapid review aims to identify the types of technologies used by people with dementia and their supporters during the COVID-19 pandemic, and the issues which influenced technology adoption within their usual care routines. METHODS: PubMed, PsychInfo, Scopus, and Cochrane COVID reviews were searched to identify peer-review studies published since 2020. A total of 18 studies were included and synthesised thematically. RESULTS: Of these, most were conducted in the community (n = 15) with people with dementia only (n = 11) and involved qualitative methods (n = 11). The majority (n = 12) focused on digital off-the-shelf and low-cost solutions, such as free video conferencing platforms, to access care, socialise or take part in interventions. Whilst often well-accepted and associated with positive outcomes (such as improved social connectedness), lack of digital literacy or support to use technologies, limited access to appropriate technology, individuals' physical, cognitive, or sensory difficulties, were highlighted and likely to threaten the adoption of these solutions. The quality of the evidence was mixed, neither very robust nor easily generalisable which may be attributed to the challenges of conducting research during the pandemic or the need to rapidly adapt to a new reality. CONCLUSION: While COVID-19 has fast-tracked the adoption of technology, its use is likely to continue beyond the pandemic. We need to ensure this technology can leverage dementia support and care and that people with dementia are enabled and empowered to use it.
Assuntos
COVID-19 , Demência , Humanos , Pandemias , Demência/psicologia , TecnologiaRESUMO
The Brazil-Malvinas Confluence (BMC) is a significant biological frontier where distinct currents meet, fostering optimal conditions for phytoplankton development. In this study we tested the hypothesis that eddys promote an increase in phytoplankton biomass at the Brazil-Malvinas Confluence (BMC), altering species diversity. Phytoplankton were collected with Niskin bottles and nutrient concentrations assessed at two depths (Surface and Deep Chlorophyll Maximum Layer - DCML) in areas outside and under the influence of Cold-Core (CCE) and Warm-Core (WCE) Eddies. Environmental variables were determined in situ using a CTD profiler. Four regions were separated based on environmental variables and phytoplankton species, namely, the Brazil Current (BC), Malvinas Current (MC), CCE, and WCE. Species diversity was higher in the eddies. The conditions of the WCE were different from those of the CCE, with low temperature and salinity and high cell density values in the latter. The phylum Bacillariophyta was predominant in terms of species richness in all regions and was responsible for the higher cell density in the MC, while dinoflagellates were dominant in the BC and eddies. Therefore, eddy activity alters the structure, diversity and biomass of the phytoplankton community in the BMC.
Assuntos
Biodiversidade , Biomassa , Fitoplâncton , Fitoplâncton/classificação , Fitoplâncton/crescimento & desenvolvimento , Brasil , Estações do Ano , Clorofila/análise , Movimentos da Água , TemperaturaRESUMO
The use of Intravascular Laser Irradiation of Blood (ILIB) as a treatment or adjunct tool has been used around the world since the 1980s. So that more professionals can deliver benefits to their patients in different areas of health, it is necessary to understand in depth the mechanisms of laser action at the molecular level, for correct indication and success in the treatment. To analyze works that evaluated the influence of ILIB on inflammatory cytokines and nitric oxide (NO) in animals and humans. The literature search was carried out between February and April 2023 in Pubmed, Medline, Web of Science, SciELO, Lilacs database. The risk of bias was assessed using the bias table where the authors performed the analyzes of all articles with the risk of bias domains. The methodology was defined following the PRISMA guidelines (Preferred Systematic Reviews and MetaAnalysis Report). The search retrieved 135 possibly relevant articles. After removing duplicates, according to the eligibility criteria, evaluation of titles and review of abstracts, in the end, 6 articles were included. An increase in anti-inflammatory cytokines, a decrease in pro-inflammatory cytokines and an increase in NO can be observed. The wavelengths used ranged from 660 to 808 nm when using a low intensity laser and when using a VIP light source 480-3400 nm, they also differed in terms of the light emission pattern. ILIB may be a complementary treatment option for patients who have comorbidities that lead to systemic inflammation.
Assuntos
Citocinas , Óxido Nítrico , Animais , Humanos , Inflamação/radioterapiaRESUMO
Salmonella spp. is among the most central etiological agents in foodborne bacterial disorders. To identify Salmonella spp., numerous new molecular techniques have been developed conversely to the traditional culture-based methods. In this work, a new peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method was developed for the specific detection of Salmonella species, allowing a faster analysis compared with the traditional methods (ISO 6579-1: 2017). The method was optimized based on a novel PNA probe (SalPNA1692) combined with a blocker probe to detect Salmonella in food samples through an assessment of diverse-rich and selective enrichment broths. Our findings indicated that the best outcome was obtained using a 24-h pre-enrichment step in buffered peptone water, followed by RambaQuick broth selective enrichment for 16 h. For the enrichment step performance validation, fresh ground beef was artificially contaminated with two ranges of concentration of inoculum: a low level (0.2-2 colony-forming units [CFUs]/25 g) and a high level (2-10 CFUs/25 g). The new PNA-FISH method presented a specificity of 100% and a detection limit of 0.5 CFU/25 g of food sample, which confirms the great potential of applying PNA probes in food analysis.
Assuntos
Microbiologia de Alimentos , Hibridização in Situ Fluorescente , Ácidos Nucleicos Peptídicos , Salmonella , Hibridização in Situ Fluorescente/métodos , Salmonella/isolamento & purificação , Salmonella/genética , Microbiologia de Alimentos/métodos , Animais , Contaminação de Alimentos/análise , Bovinos , Sensibilidade e Especificidade , Limite de Detecção , Carne Vermelha/microbiologiaRESUMO
BACKGROUND: Polyurethane (PU)-coated breast implants are known for their strong integration into breast tissue and the formation of capsules around them. However, capsular contracture can pose both aesthetic and clinical challenges. OBJECTIVES: The objectives of this study were to analyze the biological and morphological characteristics of the capsular tissue surrounding PU-coated implants, irrespective of their contracture status, and to assess their potential suitability as a flap in revisional breast surgery for capsular contracture. METHODS: A total of 23 tissue samples were harvested from the capsules surrounding PU-coated breast implants in 12 female patients during replacement or revisional surgery. We evaluated collagen abundance, cellular and vascular density, inflammation, collagen band types and alignment, synovial metaplasia, capsule thickness, and the expression of inflammatory biomarkers and myofibroblasts with immunohistochemical techniques. Scanning electron microscopy was employed to assess implant surface characteristics over time. RESULTS: We found a significant association of capsule contraction with longer implantation durations and greater implant surface roughness (P = .018 and P = .033, respectively). Synovial metaplasia was significantly more frequent in noncontracted capsules (P = .0049). Both capsule types consisted of paucicellular, type I collagen-rich compact fibrous tissue with low vascularization. There was a marked reduction in inflammatory cells within the foreign body granuloma. The expression of inflammatory biomarkers in the capsular tissue was negligible. CONCLUSIONS: Given the reduced levels of inflammatory and vascular components within the dense, fibrous capsular tissue, we consider them to be viable alternatives for capsular flaps in revisional surgery. This strategy has the potential to mimic the reconstruction achieved with acellular dermal matrix.
Assuntos
Implante Mamário , Implantes de Mama , Contratura Capsular em Implantes , Poliuretanos , Humanos , Feminino , Implantes de Mama/efeitos adversos , Adulto , Pessoa de Meia-Idade , Implante Mamário/efeitos adversos , Implante Mamário/instrumentação , Implante Mamário/métodos , Contratura Capsular em Implantes/etiologia , Contratura Capsular em Implantes/patologia , Reoperação , Materiais Revestidos Biocompatíveis , Propriedades de Superfície , Fatores de Tempo , Microscopia Eletrônica de Varredura , Desenho de Prótese , Metaplasia/patologiaRESUMO
OBJECTIVES: Genetic variants in the dihydropyrimidine dehydrogenase (DPYD ) gene are associated with reduced dihydropyrimidine dehydrogenase enzyme activity and can cause severe fluoropyrimidine-related toxicity. We assessed the frequency of the four most common and well-established DPYD variants associated with fluoropyrimidine toxicity and implemented a relatively low-cost and high-throughput genotyping assay for their detection. METHODS: This study includes 457 patients that were genotyped for the DPYD c.1129-5923C>G, c.1679T>G, c.1905 + 1G>A and c.2846A>T variants, either by Sanger sequencing or kompetitive allele specific PCR (KASP) technology. Of these, 172 patients presented toxicity during treatment with fluoropyrimidines (post-treatment group), and 285 were tested before treatment (pretreatment group). RESULTS: Heterozygous DPYD variants were identified in 7.4% of the entire series of 457 patients, being the c.2846A>T the most frequent variant. In the post-treatment group, 15.7% of the patients presented DPYD variants, whereas only 2.5% of the patients in the pretreatment group presented a variant. The KASP assays designed in this study presented 100% genotype concordance with the results obtained by Sanger sequencing. CONCLUSIONS: The combined assessment of the four DPYD variants in our population increases the identification of patients at high risk for developing fluoropyrimidine toxicity, supporting the upfront routine implementation of DPYD variant genotyping. Furthermore, the KASP genotyping assay described in this study presents a rapid turnaround time and relatively low cost, making upfront DPYD screening feasible in clinical practice.
Assuntos
Di-Hidrouracila Desidrogenase (NADP) , Neoplasias , Humanos , Di-Hidrouracila Desidrogenase (NADP)/genética , Genótipo , Alelos , Antimetabólitos , Heterozigoto , Neoplasias/tratamento farmacológico , Neoplasias/genéticaRESUMO
Brazilian quilombos are communities formed by enslaved Africans and their descendants all over the country during slavery and shortly after its abolition. Quilombos harbor a great fraction of the largely unknown genetic diversity of the African diaspora in Brazil. Thus, genetic studies in quilombos have the potential to provide important insights not only into the African roots of the Brazilian population but also into the genetic bases of complex traits and human adaptation to diverse environments. This review summarizes the main results of genetic studies performed on quilombos so far. Here, we analyzed the patterns of African, Amerindian, European, and subcontinental ancestry (within Africa) of quilombos from the five different geographic regions of Brazil. In addition, uniparental markers (from the mtDNA and the Y chromosome) studies are analyzed together to reveal demographic processes and sex-biased admixture that occurred during the formation of these unique populations. Lastly, the prevalence of known malaria-adaptive African mutations and other African-specific variants discovered in quilombos, as well as the genetic bases of health-related traits, are discussed here, together with their implication for the health of populations of African descent.
Assuntos
Aclimatação , População Africana , Nível de Saúde , Humanos , População Africana/genética , Brasil , DNA Mitocondrial , MitocôndriasRESUMO
OBJECTIVES: This study aimed to explore the practical organisational aspects and difficulties in the implementation of the molecular classification of endometrial carcinoma (EC), and to demonstrate its potential impact in prognostic risk group classification. METHODS: We conducted a multicentre, retrospective cohort study of 230 patients with EC diagnosed between 2019 and 2022. Sample processing, clinicopathological, treatment and follow-up data were collected. Molecular classification was obtained by p53 and mismatch repair proteins immunohistochemistry, and POLE next-generation sequencing. RESULTS: Implementation was achieved through centralization of molecular analysis. In practice, it was possible to optimise turnaround times of complete integrative reports for hysterectomy specimens to a median time of 18 workdays. If genetic study was started in endometrial biopsies before surgery, 82.0% were available at the time of multidisciplinary tumour board, compared to 8.4% if performed in hysterectomy. ECs were classified as follows: 37.8% no specific molecular profile, 31.7% p53 abnormal, 24.3% mismatch repair deficient, and 6.1% POLE mutant. Integration of these results with traditional clinicopathologic factors led to a change in prognostic risk group in 15 (6.5%) patients, most being initially allocated to high-intermediate (n = 8) and low (n = 5) risk groups. Eight patients changed to a higher risk, and 7 to a lower risk group, whereas 2 remained in the same group. CONCLUSIONS: Centralization of EC molecular classification is a feasible option for countries with limited resources. Optimization of workflows may be achieved by earlier analysis in biopsies and prioritisation of patients whose results imply changes in risk group classification.
Assuntos
Neoplasias do Endométrio , Proteína Supressora de Tumor p53 , Feminino , Humanos , Proteína Supressora de Tumor p53/genética , Estudos Retrospectivos , Neoplasias do Endométrio/patologia , Prognóstico , Fatores de Risco , MutaçãoRESUMO
Global population growth tremendously impacts the global food industry, endangering food safety and quality. Mycotoxins, particularly Ochratoxin-A (OTA), emerge as a food chain production threat, since it is produced by fungus that contaminates different food species and products. Beyond this, OTA exhibits a possible human toxicological risk that can lead to carcinogenic and neurological diseases. A selective, sensitive, and reliable OTA biodetection approach is essential to ensure food safety. Current detection approaches rely on accurate and time-consuming laboratory techniques performed at the end of the food production process, or lateral-flow technologies that are rapid and on-site, but do not provide quantitative and precise OTA concentration measurements. Nanoengineered optical biosensors arise as an avant-garde solution, providing high sensing performance, and a fast and accurate OTA biodetection screening, which is attractive for the industrial market. This review core presents and discusses the recent advancements in optical OTA biosensing, considering engineered nanomaterials, optical transduction principle and biorecognition methodologies. Finally, the major challenges and future trends are discussed, and current patented OTA optical biosensors are emphasized for a particular promising detection method.
RESUMO
Persistent organic pollutants (POPs) were analyzed in 136 blubber samples of Franciscana dolphins from Brazil (Pontoporia blainvillei), which is the most threatened dolphin in the Southwestern Atlantic. The dolphins were caught by the fishery fleet and collected from 2000 to 2018 in three regions of São Paulo state: northern São Paulo (SPN), central São Paulo (SPC), and southern São Paulo (SPS). The POPs analyzed in this study were polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDTs), Mirex, hexachlorobenzene (HCB), chlordane compounds (CHLs), hexachlorocyclohexane isomers (HCHs), and polybrominated diphenyl ethers (PBDEs). The concentrations ranged from 36 to 7200 ng g-1 lipid weight (lw) and 113-42200 ng g-1 lw for predominant compounds DDTs and PCBs, respectively. Similar profiles of PCB congeners were observed with a predominance of hexachlorinated compounds, representing approximately 50% of the total PCB amount; the highest PCB concentrations were observed from Baixada Santista (SPC) proximate to a highly urbanized and industrial coastal area. Significant differences were observed between the sexes and maturity of dolphins, mainly for PCBs, DDTs, and Mirex. In general, POPs other than HCB in Franciscana dolphins showed downward temporal trends, matching the regulatory periods for restricting and/or banning these compounds. Although POP concentrations are declining, PCB levels remain high in small dolphins, suggesting adverse health effects on Franciscanas. As organic contaminants are one of the numerous threats Franciscanas have been vulnerable to along the Brazilian coast, we recommend monitoring POPs levels every five years to check for declining (or stabilizing) trends.
Assuntos
Golfinhos , Poluentes Ambientais , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Bifenilos Policlorados/análise , Hexaclorobenzeno , Poluentes Orgânicos Persistentes , Mirex , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Brasil , Éteres Difenil Halogenados/análise , DDTRESUMO
AIM: This study aimed to evaluate the volumetric change of root canal sealers through micro-computed tomographic analysis using a novel in vivo model and to compare the results with those obtained using an ex vivo test. METHODOLOGY: Eighteen single-rooted teeth were cut to 5 mm length from the root apex. The root canals were uniformly enlarged and filled with EndoSequence BC Sealer or AH Plus Jet root canal sealers. Samples were stored at 37°C and 95% relative humidity for 24 h and then scanned with a micro-CT device. Twelve samples (n = 6 for each sealer) were implanted in the subcutaneous tissue of Wistar rats, while six samples (n = 3 for each sealer) were immersed in 20 mL of phosphate-buffered saline (PBS) at 37°C at neutral pH. After 7 and 30 days, teeth were removed from subcutaneous tissue or PBS and rescanned. Statistical analysis of volume changes was performed using Shapiro-Wilk's test and independent t-test (p < .05). RESULTS: AH Plus Jet had smaller volume changes (-2.2 to +0.77%) than EndoSequence BC Sealer (-2.0 to +4.0%) (p < .05), in the two tested models. The volume of the root canal sealers decreased over time (p < .05), in vivo. AH Plus Jet results varied between the in vivo and ex vivo results (p < .05), while EndoSequence BC Sealer presented similar volume losses for both experimental models (p > .05). CONCLUSION: EndoSequence BC Sealer lost more volume than AH Plus Jet. The experimental conditions influenced the volumetric change of AH Plus Jet but not the EndoSequence BC Sealer. The ex vivo model should be further explored as a methodological alternative to assess the volumetric changes of root canal sealers without causing harm to animals.
Assuntos
Materiais Restauradores do Canal Radicular , Ratos , Animais , Resinas Epóxi , Cavidade Pulpar , Ratos Wistar , Concentração de Íons de Hidrogênio , Silicatos , Teste de MateriaisRESUMO
Understanding how nanoparticles' properties influence their cellular interactions is a bottleneck for improving the design of carriers. Macrophage polarization governs their active role in solving infections or tissue repair. To unravel the effect of carbohydrate-targeting mannose receptors on the macrophage surface, drug-free fucoidan/chitosan nanoparticles were functionalized using mannose (M) and mannan (Mn). Polyelectrolyte complex nanoparticles were obtained upon chitosan self-assembly using fucoidan. The functionalized nanoparticles were characterized in terms of their physicochemical characteristics, chemical profile, and carbohydrate orientation. The nanoparticles varied in size from 200 to 400 nm, were monodisperse, and had a stable negative zeta potential with a low aggregation tendency. The nonfunctionalized and functionalized nanoparticles retained their properties for up to 12 weeks. Cell viability and internalization studies were performed for all the designed nanoparticles in the THP-1 monocytes and THP-1-differentiated macrophages. The expression of the mannose receptor was verified in both immune cells. The carbohydrate-functionalized nanoparticles led to their activation and the production of pro-inflammatory cytokines interleukin (IL)-1ß, IL-6, and tumour necrosis factor (TNF)-α. Both M- and Mn-coated nanoparticles modulate macrophages toward an M1-polarized state. These findings demonstrate the tailoring of these nanoplatforms to interact and alter the macrophage phenotype in vitro and represent their therapeutic potential either alone or in combination with a loaded drug for future studies.
Assuntos
Quitosana , Nanopartículas , Receptor de Manose , Quitosana/farmacologia , Quitosana/metabolismo , Macrófagos/metabolismo , Nanopartículas/química , Manose/metabolismoRESUMO
Although the exact mechanism of the pathogenesis of coronavirus SARS-CoV-2 (COVID-19) is not fully understood, oxidative stress and the release of pro-inflammatory cytokines have been highlighted as playing a vital role in the pathogenesis of the disease. In this sense, alternative treatments are needed to reduce the level of inflammation caused by COVID-19. Therefore, this study aimed to investigate the potential effect of red photobiomodulation (PBM) as an attractive therapy to downregulate the cytokine storm caused by COVID-19 in a zebrafish model. RT-qPCR analyses and protein-protein interaction prediction among SARS-CoV-2 and Danio rerio proteins showed that recombinant Spike protein (rSpike) was responsible for generating systemic inflammatory processes with significantly increased levels of pro-inflammatory (il1b, il6, tnfa, and nfkbiab), oxidative stress (romo1) and energy metabolism (slc2a1a and coa1) mRNA markers, with a pattern similar to those observed in COVID-19 cases in humans. On the other hand, PBM treatment was able to decrease the mRNA levels of these pro-inflammatory and oxidative stress markers compared with rSpike in various tissues, promoting an anti-inflammatory response. Conversely, PBM promotes cellular and tissue repair of injured tissues and significantly increases the survival rate of rSpike-inoculated individuals. Additionally, metabolomics analysis showed that the most-impacted metabolic pathways between PBM and the rSpike treated groups were related to steroid metabolism, immune system, and lipid metabolism. Together, our findings suggest that the inflammatory process is an incisive feature of COVID-19 and red PBM can be used as a novel therapeutic agent for COVID-19 by regulating the inflammatory response. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials can commence.
Assuntos
COVID-19 , Animais , Humanos , Peixe-Zebra/metabolismo , SARS-CoV-2/metabolismo , Síndrome da Liberação de Citocina , Citocinas/metabolismo , RNA Mensageiro , Proteínas de Membrana , Proteínas MitocondriaisRESUMO
The impact of water deficit on sucrose metabolism in sink organs like the fruit remains poorly known despite the need to improve fruit crops resilience to drought in the face of climate change. The present study investigated the effects of water deficit on sucrose metabolism and related gene expression in tomato fruits, aiming to identify candidate genes for improving fruit quality upon low water availability. Tomato plants were subjected to irrigated control and water deficit (-60% water supply compared to control) treatments, which were applied from the first fruit set to first fruit maturity stages. The results have shown that water deficit significantly reduced fruit dry biomass and number, among other plant physiological and growth variables, but substantially increased the total soluble solids content. The determination of soluble sugars on the basis of fruit dry weight revealed an active accumulation of sucrose and concomitant reduction in glucose and fructose levels in response to water deficit. The complete repertoire of genes encoding sucrose synthase (SUSY1-7), sucrose-phosphate synthase (SPS1-4), and cytosolic (CIN1-8), vacuolar (VIN1-2) and cell wall invertases (WIN1-4) was identified and characterized, of which SlSUSY4, SlSPS1, SlCIN3, SlVIN2, and SlCWIN2 were shown to be positively regulated by water deficit. Collectively, these results show that water deficit regulates positively the expression of certain genes from different gene families related to sucrose metabolism in fruits, favoring the active accumulation of sucrose in this organ under water-limiting conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01288-7.