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1.
J Clin Pediatr Dent ; 48(5): 102-109, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39275826

RESUMO

Nickel-titanium (NiTi) instruments offer many advantages during endodontic instrumentation; however, the fracture risk within the canal remains a concern. Manufacturers continuously develop and introduce instruments to the market with supposedly enhanced cyclic fatigue resistance and increased flexibility, achieved through different proprietary manufacturing processes, the details of which have not been made public. In recent years, two rotary systems specially designed for deciduous teeth have been commercially available, but information about their performance is lacking. This investigation aimed to identify which manufacturing process provides better cyclic fatigue resistance: the AF-H Wire technology used in the AF baby rotary files (AF-f) or the CM-Wire technology used in the i3 Gold deciduous teeth rotary files (i3G-f). Forty rotary International Organization for Standardization (ISO) 25/04 files were tested in artificial canals with a standard geometry of 60° angle and 2.5 mm radius until fracture. The number of cycles to fracture was calculated, and the length of the fragments was measured. A scanning electron microscope (SEM) was used to examine the fracture surfaces and fragments. Energy dispersive spectroscopy (EDS) was used to determine the percentage weight of NiTi in each file. The statistical analysis (Mann-Whitney test) showed that the cyclic fatigue resistance of the AF-f was significantly higher (p < 0.0001) than that of the i3G-f. Additionally, there was a significant difference (p = 0.0419) in the length of the fractured fragments. All instruments showed one or more types of manufacturing defects and presented similar NiTi percentages by weight. The manufacturing process is critical to cyclic fatigue resistance, and there seems to be responsible for the difference in cyclic fatigue resistance between these similar instruments.


Assuntos
Falha de Equipamento , Temperatura Alta , Níquel , Preparo de Canal Radicular , Titânio , Preparo de Canal Radicular/instrumentação , Níquel/química , Humanos , Titânio/química , Desenho de Equipamento , Teste de Materiais , Instrumentos Odontológicos , Microscopia Eletrônica de Varredura , Ligas Dentárias/química , Técnicas In Vitro , Análise do Estresse Dentário
2.
Plants (Basel) ; 12(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771743

RESUMO

The present study analyzed Medicago sativa L. crops irrigated by TiO2 in the anatase phase and TiO2 doped with Ag, Fe, and Cu ions at 0.1%w synthesized using the sol-gel method (SG) and the sol-gel method coupled with microwave (Mw-SG). The materials were added to the irrigation water at different concentrations (50, 100, and 500 ppm). Stress induction by nanomaterials was observed by measuring stem morphology, chlorophyll index, total phenols and flavonoids, and antioxidant activity through the DPPH (2,2-diphenyl-1-picrylhydrazy) radical inhibition assay. The nanomaterial treatments caused statistically significant reductions in parameters such as stem length, leaf size, and chlorophyll index and increases in total phenol content and DPPH inhibition percentage. However, the observed effects did not show clear evidence regarding the type of nanomaterial used, its synthesis methodology, or a concentration-dependent response. By generally grouping the results obtained to the type of dopant used and the synthesis method, the relationship between them was determined employing a two-way ANOVA. It was observed that the dopant factors, synthesis, and interaction were relevant for most treatments. Additionally, the addition of microwaves in the synthesis method resulted in the largest number of treatments with a significant increase in the total content of phenols and the % inhibition compared to the traditional sol-gel synthesis. In contrast, parameters such as stem size and chlorophyll index were affected under different treatments from both synthesis methods.

3.
Int J Psychol ; 58(3): 196-206, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36807908

RESUMO

As of 2021, over 5.4 million Venezuelans have fled their home country in search of safety, food, medicine and access to essential services. This is the most substantial exodus in the recent history of Latin America. Colombia has received 2 million of these refugees, making it the nation host to the greatest number of Venezuelan refugees. The present research aims to examine the relations between the sociocultural and psychological factors that are associated with Psychological Adaptation of Venezuelan refugees living in Colombia. We also examined how these relations were mediated by the acculturation orientations. Among Venezuelan refugees, higher Psychological Strength, lower Perceived Discrimination, higher National Identity and higher Outgroup Social Support, were significantly associated with higher engagement with Colombian society and better Psychological Adaptation. Orientation to the host (Colombian) society mediated the association between (a) National Identity and Psychological Adaptation, (b) Outgroup Social Support and Psychological Adaptation and (c) Perceived Discrimination and Psychological Adaptation. The results may inform refugee receiving societies of some essential factors and positive strategies behind adaptation of refugees.


Assuntos
Aculturação , Refugiados , Humanos , Refugiados/psicologia , Colômbia , Ajustamento Emocional , Adaptação Psicológica
4.
Braz. J. Pharm. Sci. (Online) ; 59: e20555, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1429956

RESUMO

Abstract Cannabis sativa L. is one of the most consumed drugs in the world and recent studies have associated its use with an increase in the number of traffic accidents in different countries. In many countries, like Brazil, simple and reliable methodologies are still needed for the detection of drugs on site, mainly cannabinoids, considering its prevalence of use and oral fluid (OF) has been proved as an appropriate biological matrix for this purpose. Considering that, this work aims to review previous studies on immunochromatographic devices for on-site detection of cannabinoids in OF, discussing their sensitivity, specificity, cut-offs values and confirmatory methods. This data shows the importance of choosing a screening device and it reinforces the need for its implementation in Brazil. The research was conducted on 5 databases and all original articles, published in the last 10 years, were selected. A total of 32 articles were found, providing data for 17 screening devices of distinct brands. Only 2 screening devices showed satisfactory sensitivity and specificity in the evaluated studies (≥80% and ≥90% respectively). However, it should be considered that the screening devices still have some limitations, such as a higher cut-off than those recommended by international guidelines (cut-off > 2 ng/mL), therefore demonstrating the need for more studies in the area and the importance of confirmatory analysis usually fulfilled by LC-MS/MS, GC-MS/MS or GC-MS. Thus, the screening analyzes should not be evaluated by itself, but in association with confirmatory results and observational traits (behavioral changes), for a better understanding of the traffic scenario


Assuntos
Canabinoides/análise , Triagem/classificação , Cromatografia de Afinidade/instrumentação , Dronabinol/agonistas , Cannabis/efeitos adversos , Acidentes de Trânsito/prevenção & controle , Detecção do Abuso de Substâncias/instrumentação
5.
Trop Med Infect Dis ; 7(12)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36548700

RESUMO

Trypanosoma cruzi, the causal agent of Chagas disease, is mainly transmitted by insects of the Triatominae subfamily. In Colombia, there are 26 triatomine species, and 16 of them are naturally infected with the parasite. The parasite loads of naturally infected vectors can be significant in targeting specific species that can affect the epidemiology of the disease. Studying their ecology and behavior is vital to understand their role in T. cruzi transmission dynamics. We evaluated the parasite loads of 182 field-collected triatomines corresponding to 10 species in 13 departments across Colombia. We standardized a methodology to quantify T. cruzi DNA in these insects. We obtained a LOD (limit of detection) of 3.05 p-eq/mL. The 82% of triatomines we evaluated were positive for T. cruzi infection, with loads ranging from hundreds to millions of equivalent parasites per milliliter. Panstrongylus geniculatus, Rhodnius prolixus, and Triatoma dimidiata were the species with the highest loads of T. cruzi; however, other species whose role as vectors is still unknown were also found with high loads of parasites. Our results suggest the relevance of secondary species for T. cruzi transmission in Colombia. We hope our data can help improve entomological surveillance and vector control programs in the country and the region.

6.
Nanomaterials (Basel) ; 12(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683797

RESUMO

The problem of water pollution by persistent substances and microorganisms requires solutions that materials such as silver-modified titanium dioxide can provide due to their excellent photocatalytic and antimicrobial properties. However, the synthesis methods conventionally used to obtain these materials involve toxic chemical reagents such as sodium borohydride (NaBH4). The search for alternative synthesis methods that use environmentally friendly substances, such as the biosynthesis method, was evaluated. Silver-titanium dioxide (Ag-TiO2) was synthesized by a Eucalyptus globulus L. extract as a reductive agent through sol-gel and microwave-assisted sol-gel processes. Four different solvents were tested to extract secondary metabolites to determine their roles in reducing silver nanoparticles. Titanium dioxide nanoparticles with sizes from 11 to 14 nm were obtained in the anatase phase, and no narrowing of the bandgap was observed (3.1-3.2 eV) for the Ag-TiO2 materials compared with the pure TiO2. Interestingly, the bacterial inhibition values were close to 100%, suggesting an effective antimicrobial mechanism related to the properties of silver. Finally, by the physicochemical characterization of the materials and their antimicrobial properties, it was possible to obtain a suitable biosynthesized Ag-TiO2 material as a green option for water disinfection that may be compared to the conventional methods.

7.
Ginecol. obstet. Méx ; Ginecol. obstet. Méx;90(3): 207-213, ene. 2022. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1385015

RESUMO

Resumen OBJETIVO: Conocer el grado de aceptación de la autotoma vaginal y su relación con variables psicosocioculturales que prevalecen en México. MATERIALES Y MÉTODOS: Estudio observacional, prospectivo, transversal y descriptivo, efectuado entre 2017 y 2018 en mujeres del estado de Guanajuato. Se aplicaron cuestionarios y entrevistas antes y después de la toma de la muestra mediante la autotoma. El análisis estadístico incluyó medidas de tendencia central, medidas de dispersión, frecuencias y proporciones. Las diferencias entre grupos se analizaron con las pruebas de Wilcoxon y t de Student. RESULTADOS: Se estudiaron 85 mujeres con edad promedio de 37.82 años (± 9.82). Si bien 75 participantes declararon no conocer el procedimiento, 80 accedieron a practicarlo. Se encontró que la mayoría de las mujeres prefiere la autotoma a la inspección ginecológica tradicional. Se observaron dos perfiles sociopsicológicos opuestos entre las mujeres que prefieren la autotoma por "pena" y las que optan por ella por su "facilidad". CONCLUSIONES: La autotoma fue un método de muestreo completamente viable en el contexto en el que se llevó a cabo esta investigación. Si bien se observaron barreras psicosocioculturales, la autotoma se prefirió entre las mujeres que informaron acudir menos al ginecólogo, por lo que puede constituir una estrategia para las mujeres con baja vigilancia médica.


Abstract OBJECTIVE: To know the degree of acceptance of vaginal autotomy and its relationship with psychosocial-cultural variables prevailing in Mexico. MATERIALS AND METHODS: Observational, prospective, cross-sectional and descriptive study, carried out between 2017 and 2018 in women in the state of Guanajuato. Questionnaires and interviews were applied before and after sampling by autotoma. Statistical analysis included measures of central tendency, measures of dispersion, frequencies and proportions. Differences between groups were analyzed with Wilcoxon and Student's t-tests. RESULTS: Eighty-five women with a mean age of 37.82 years (± 9.82) were studied. Although 75 participants stated that they were unaware of the procedure, 80 agreed to undergo it. It was found that the majority of women preferred autotoma to traditional gynecological inspection. Two opposite socio-psychological profiles were observed between women who prefer autotomy for "embarrassment" and those who opt for it because of its "ease". CONCLUSIONS: Autotomography was a completely feasible sampling method in the context in which this research was conducted. Although psychosocio-cultural barriers were observed, autotoma was preferred among women who reported less frequent visits to the gynecologist, so it may be a strategy for women with low medical vigilance.

8.
Brain Sci ; 11(7)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34356167

RESUMO

This study aims to find causal factors of aggression in a group of Latino adolescents to achieve a greater understanding of human nature, taking into account personal and contextual variables. The fundamental hypothesis is that moral disengagement, personality traits, self-esteem, values, parenting, sex, and socioeconomic situation can function as possible casual factors of aggression in adolescents. The study examined the variables using the structural equations model (SEM) to determine causal factors of aggression in a sample of 827 adolescents (54% men and 46% women) between 11 and 16 years of age. According to the scientific literature review, sociodemographic, personal, and familiar variables were included in the causal model. The influence of the variables occurred in two ways: one that inhibits aggression and the other that reinforces it. The results are discussed based on identifying protective and risk factors against aggression: biological sex and values of conformity and transcendence as aggression's inhibitors and, on the other hand, openness, moral disengagement, and leadership values as the most important predictors of aggression.

9.
J Forensic Sci ; 66(6): 2104-2112, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34405898

RESUMO

Cannabis sativa L. is a substance widely used around the world for recreational and medicinal purposes. Oral fluid has been investigated as an alternative biological matrix for demonstrating the illegal use of cannabis, particularly in situations where its recent use needs to be identified. In the last two decades, many methods have been developed to detect and quantify cannabinoids in oral fluid, especially for Δ9 -tetrahydrocannabinol, the primary psychoactive substance of cannabis. However, some aspects must be considered in the use of these techniques, such as cannabinoids recoveries or extraction efficiency from different oral fluid collection devices/containers. Pharmacokinetic studies have shown that the presence of minor cannabinoids and metabolites in the analysis of oral fluid may be valuable in interpreting tests, which indicates the need to improve the sensitivity of detecting low concentrations. The aim of this review is to summarize and to describe the methodologies for the quantitative analysis of cannabinoids in oral fluid that have previously been investigated. A systematic search for articles was performed of four different databases, using the descriptor "cannabinoids and oral fluid". Forty-seven studies that examined quantitative methods were identified. The analytical data described in these articles, including oral fluid collection, sample preparation, cannabinoids recovery and extraction efficiency, detection instruments, and quantification limits, were analyzed. The discussion of these particular features of cannabinoid analysis in oral fluid could help to improve or to develop methods for use in Forensic Toxicology.


Assuntos
Canabinoides/análise , Saliva/química , Detecção do Abuso de Substâncias/métodos , Cromatografia Gasosa , Cromatografia Líquida , Toxicologia Forense/métodos , Humanos , Extração Líquido-Líquido , Espectrometria de Massas , Extração em Fase Sólida
10.
Artigo em Inglês | MEDLINE | ID: mdl-34203001

RESUMO

This research analyzes the decisions made by women facing simulated situations of psychological abuse. Seventy-three women (36.9 ± 13.6 years) who had been victims of domestic violence participated. The analysis was based on their coping strategies, early maladaptive schemes, and their decisions in response to vignettes describing the following domestic violence situations: humiliation to women's maternal identity with children as witnesses and body shaming. We used Student's t and Mann-Whitney tests to compare the results between groups. The participants presented some coping strategies (social support seeking, wishful thinking, and professional support seeking) and several early maladaptive schemes (emotional deprivation, defectiveness/shame, social isolation/alienation, failure to achieve, attachment, and subjugation) associated with their reactions facing a situation of humiliation with children as witnesses. When the humiliation was against the body image, their reactions were associated with some coping strategies (wishful thinking, professional support seeking, autonomy, negative auto-focus coping, and positive reappraisal) and one maladaptive scheme (defectiveness/shame). Women who reacted avoidantly showed higher social and professional support seeking but experienced higher indicators of discomfort and deterioration of self-esteem than those who opted for assertive decisions. The presence of children as witnesses seems to be a factor of stress in the configuration of coping strategies and maladaptive schemes in female victims of domestic violence. The evolution of early maladaptive schemes and coping strategies requires observation to avoid the risk of isolation and permanence in victimizing relationships.


Assuntos
Adaptação Psicológica , Abuso Emocional , Criança , Família , Feminino , Humanos , Vergonha , Apoio Social
11.
Rev. cuba. salud pública ; Rev. cuba. salud pública;47(2): e2267, 2021. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1341488

RESUMO

Introducción: En Colombia se realizan programas de intervención psicosocial en comunidades con desventaja socioeconómica para mejorar su calidad de vida, sin embargo, no se realizan evaluaciones de impacto para medir su efectividad. Objetivo: Determinar la relación que existe entre el tiempo de exposición a procesos de intervención psicosocial en comunidades en desventaja socioeconómica, con su percepción de bienestar psicológico, bienestar social y capital social, en el área metropolitana de Barranquilla. Métodos: investigación fue de corte explicativo ex post facto, con una muestra de 135 personas mayores de 17 años. Se hizo un análisis de varianza para encontrar la dependencia entre los procesos de intervención y las variables dependientes. Resultados: Se encontró una relación de significancia entre el grupo etario de los participantes y algunas dimensiones del bienestar psicológico, del bienestar social y del capital social. No se encontraron relaciones significativas entre el tiempo de intervención y las variables dependientes mencionadas. Conclusiones: A pesar de la vulnerabilidad del entorno, las comunidades intervenidas participantes del estudio evidenciaron una percepción de bienestar psicológico y social y de valoración positiva de su capital social sin una relación significativa con el tiempo de exposición al trabajo comunitario. Los procesos de intervención psicosocial tienen el potencial suficiente para favorecer la mejora de las condiciones de las personas, grupos o comunidades, pero requieren de la implementación de procesos de evaluación que permitan hacer seguimiento a su impacto(AU)


Introduction: Colombia psychosocial intervention programs are carried out in communities with socioeconomic disadvantage to improve their quality of life; however, no impact's assessments are carried out to measure their effectiveness. Objective: Determine the relation between the time of exposure to psychosocial intervention's processes in communities at socioeconomic disadvantage, and their perception of psychological well-being, social welfare and social capital, in the metropolitan area of Barranquilla. Methods: The research was ex post facto explanatory one, with a sample of 135 people over the age of 17. A variance analysis was done to find the dependency between intervention processes and dependent variables. Results: A relationship of significance was found between the age group of the participants and some dimensions of psychological well-being, social welfare and social capital. No significant relationships were found between the intervention time and the dependent variables mentioned. Conclusions: Despite the vulnerability of the environment, the communities involved in the study demonstrated a perception of psychological and social well-being and positive assessment of their social capital without a significant relationship with the time of exposure to community work. Psychosocial intervention's processes have sufficient potential to promote the improvement of the conditions of individuals, groups or communities, but they require the implementation of assessment processes that allow to follow up on their impact(AU)


Assuntos
Humanos , Masculino , Feminino , Fatores Socioeconômicos , Características de Residência , Capital Social , Intervenção Psicossocial/métodos , Promoção da Saúde , Classe Social , Colômbia
12.
Photochem Photobiol Sci ; 20(4): 489-499, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33825180

RESUMO

Photodynamic therapy (PDT) is an effective procedure for the treatment of lesions diseases based on the selectivity of a photosensitising compound with the ability to accumulate in the target cell. Atherosclerotic plaque is a suitable target for PDT because of the preferential accumulation of photosensitisers in atherosclerotic plaques. Dendrimers are hyperbranched polymers conjugated to drugs. The dendrimers of ALA hold ester bonds that inside the cells are cleaved and release ALA, yielding PpIX production. The dendrimer 6m-ALA was chosen to perform this study since in previous studies it induced the highest porphyrin macrophage: endothelial cell ratio (Rodriguez et al. in Photochem Photobiol Sci 14:1617-1627, 2015). We transformed Raw 264.7 macrophages to foam cells by exposure to oxidised LDLs, and we employed a co-culture model of HMEC-1 endothelial cells and foam cells to study the affinity of ALA dendrimers for the foam cells. In this work it was proposed an in vitro model of atheromatous plaque, the aim was to study the selectivity of an ALA dendrimer for the foam cells as compared to the endothelial cells in a co-culture system and the type of cell death triggered by the photodynamic treatment. The ALA dendrimer 6m-ALA showed selectivity PDT response for foam cells against endothelial cells. A light dose of 1 J/cm2 eliminate foam cells, whereas less than 50% of HMEC-1 is killed, and apoptosis cell death is involved in this process, and no necrosis is present. We propose the use of ALA dendrimers as pro-photosensitisers to be employed in photoangioplasty to aid in the treatment of obstructive cardiovascular diseases, and these molecules can also be employed as a theranostic agent.


Assuntos
Ácido Aminolevulínico/farmacologia , Apoptose/efeitos dos fármacos , Células Espumosas/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Ácido Aminolevulínico/química , Animais , Linhagem Celular , Técnicas de Cocultura , Células Espumosas/fisiologia , Humanos , Macrófagos/fisiologia , Camundongos , Fármacos Fotossensibilizantes/química
13.
Brain Sci ; 11(4)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916876

RESUMO

We analyzed gender and anxiety differences in middle school students facing a physical peer aggression situation. The participants were 1147 adolescents aged between 12 and 18 years (male: n = 479; female: n = 668) who watched a 12 s animation representing the situation and filled out a questionnaire to analyze the legitimation of violent behaviors and anxiety levels. We registered their decisions to solve the situation using a categorical scale that included assertive, avoidant, aggressive, submissive, and supportive behaviors. Gender was not associated with the adolescent's behaviors in facing a simulated peer aggression situation. However, male teenagers tended to perceive adults as sanctioners and neutrals; those who used the diffusion of responsibility and dehumanization to justify their behavior also showed a higher state of anxiety. Female teenagers who expected legitimation from their peers, presented higher anxiety as well. Educational interventions may use these results, helping adolescents to understand that their acts have substantial implications in the lives of others. It is essential to develop group interventions that modify how adolescents manage their conflicts and change gender stereotypes that significantly impact health. We highlight the need for linking families in educational programs facing the challenges of transforming the legitimization of violence in parental practices.

14.
Data Brief ; 35: 106829, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33718538

RESUMO

This article contains data for the self-association of pyrene-labelled single Cys-mutants of apolipoprotein A-I (apoA-I). Mathematical models were developed to characterise the self-association events at different cysteine positions on apoA-I obtained as a function of protein concentration based on the multi-parametric spectrum of pyrene, particularly P-value and excimer emissions. The present work complements data related to the article entitled "Analysis of pyrene-labelled apolipoprotein A-I oligomerisation in solution: Spectra deconvolution and changes in P-value and excimer formation" Tárraga et al. [1].

15.
Eur J Pharm Biopharm ; 160: 42-54, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33440242

RESUMO

Nanoarchaeosomes are non-hydrolysable nanovesicles made of archaeolipids, naturally functionalised with ligand for scavenger receptor class 1. We hypothesized that nitrogenate bisphosphonate alendronate (ALN) loaded nanoarchaeosomes (nanoarchaeosomes(ALN)) may constitute more efficient macrophage targeted apoptotic inducers than ALN loaded nanoliposomes (nanoliposomes (ALN)). To that aim, ALN was loaded in cholesterol containing (nanoARC-chol(ALN)) or not (nanoARC(ALN)) nanoarchaeosomes. Nanoarchaeosomes(ALN) (220-320 nm sized, ~ -40 mV ξ potential, 38-50 µg ALN/mg lipid ratio) displayed higher structural stability than nanoliposomes(ALN) of matching size and ξ potential, retaining most of ALN against a 1/200 folds dilution. The cytotoxicity of nanoARC(ALN) on J774A.1 cells, resulted > 30 folds higher than free ALN and nanoliposomes(ALN) and was reduced by cholesterol in nanoARC-chol(ALN). Devoid of ALN, nanoARC-chol was non-cytotoxic, exhibited pronounced anti-inflammatory activity on J774.1 cells, strongly reducing reactive oxygen species (ROS) and IL-6 induced by LPS. Nanoarchaeosomes bilayer extensively interacted with serum proteins but resulted refractory to phospholipases. Upon J774A.1 cells uptake, nanoarchaeosomes induced cytoplasmic acid vesicles, reduced the mitochondrial membrane potential by 20-40 % without consuming ATP neither damaging lysosomes and increasing pERK. Refractory to chemoenzymatic attacks, either void or drug loaded, nanoarchaeosomes induced either anti-inflammation or macrophages apoptosis, constituting promising targeted nanovesicles for multiple therapeutic purposes.


Assuntos
Alendronato/administração & dosagem , Archaea/química , Bicamadas Lipídicas/química , Macrófagos/efeitos dos fármacos , Nanopartículas/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Lipídeos , Lipossomos , Macrófagos/patologia , Camundongos , Tamanho da Partícula
16.
Biochim Biophys Acta Gen Subj ; 1865(1): 129732, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32946930

RESUMO

BACKGROUND: The identification of dysfunctional human apolipoprotein A-I (apoA-I) in atherosclerotic plaques suggests that protein structure and function may be hampered under a chronic pro inflammatory scenario. Moreover, the fact that natural mutants of this protein elicit severe cardiovascular diseases (CVD) strongly indicates that the native folding could shift due to the mutation, yielding a structure more prone to misfold or misfunction. To understand the events that determine the failure of apoA-I structural flexibility to fulfill its protective role, we took advantage of the study of a natural variant with a deletion of the residue lysine 107 (K107del) associated with atherosclerosis. METHODS: Biophysical approaches, such as electrophoresis, fluorescence and spectroscopy were used to characterize proteins structure and function, either in native conformation or under oxidation or intramolecular crosslinking. RESULTS: K107del structure was more flexible than the protein with the native sequence (Wt) but interactions with artificial membranes were preserved. Instead, structural restrictions by intramolecular crosslinking impaired the Wt and K107del lipid solubilization function. In addition, controlled oxidation decreased the yield of the native dimer conformation for both variants. CONCLUSIONS: We conclude that even though mutations may alter protein structure and spatial arrangement, the highly flexible conformation compensates the mild shift from the native folding. Instead, post translational apoA-I modifications (probably chronic and progressive) are required to raise a protein conformation with significant loss of function and increased aggregation tendency. GENERAL SIGNIFICANCE: The results learnt from this variant strength a close association between amyloidosis and atherosclerosis.


Assuntos
Apolipoproteína A-I/metabolismo , Aterosclerose/metabolismo , Processamento de Proteína Pós-Traducional , Apolipoproteína A-I/química , Apolipoproteína A-I/genética , Aterosclerose/genética , Humanos , Lipídeos de Membrana/metabolismo , Mutação , Oxirredução , Conformação Proteica
17.
Atherosclerosis ; 316: 1-7, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33260006

RESUMO

BACKGROUND AND AIMS: The transition of macrophage to foam cells is a major hallmark of early stage atherosclerotic lesions. This process is characterized by the accumulation of large cytoplasmic lipid droplets containing large quantities of cholesterol esters (CE), triacylglycerol (TAG) and phospholipid (PL). Although cholesterol and CE metabolism during foam cell formation has been broadly studied, little is known about the role of the glycerolipids (TAG and PL) in this context. Here we studied the contribution of glycerolipid synthesis to lipid accumulation, focusing specifically on the first and rate-limiting enzyme of the pathway: glycerol-3-phosphate acyltransferase (GPAT). METHODS: We used RAW 264.7 cells and bone marrow derived macrophages (BMDM) treated with oxidized LDL (oxLDL). RESULTS: We showed that TAG synthesis is induced during the macrophage to foam cell transition. The expression and activity of GPAT3 and GPAT4 also increased during this process, and these two isoforms were required for the accumulation of cell TAG and PL. Compared to cells from wildtype mice after macrophage to foam cell transition, Gpat4-/- BMDM released more pro-inflammatory cytokines and chemokines, suggesting that the activity of GPAT4 could be associated with a decrease in the inflammatory response, probably by sequestering signaling precursors into lipid droplets. CONCLUSIONS: Our results provide evidence that TAG synthesis directed by GPAT3 and GPAT4 is required for lipid droplet formation and the modulation of the inflammatory response during the macrophage-foam cell transition.


Assuntos
Células Espumosas , Gotículas Lipídicas , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Animais , Glicerol , Glicerol-3-Fosfato O-Aciltransferase/genética , Lipoproteínas LDL , Macrófagos , Camundongos , Fosfatos , Triglicerídeos
18.
Data Brief ; 33: 106536, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33304951

RESUMO

This article shows the dataset of clearance assays and the reconstitution of stable biological nano-complexes using both detergent-assisted and spontaneous solubilization of phospholipids by the recombinant purified apolipoprotein A-I (apoA-I). Protein was intra-chain crosslinked in order to introduce steric constrains. Then, native and crosslinked protein function was evaluated by a data collection of dimiristoyl phosphatidyl choline (DMPC) micellization curves. Additionally, resulting particles from spontaneous or detergent-assisted lipid solubilization were characterized by transmission electron microscopy (TEM), size exclusion chromatography (SEC), and native polyacrylamide gel electrophoresis (PAGE). Here we set up an experimental design that may help study protein structure based on its function, since interaction with biological membranes and lipids is an intrinsic activity attributed to many proteins in circulation. In addition, by t-test analysis of collected-data, we examined the formation of lipoprotein particles by native and intra-chain crosslinked proteins under different conditions like temperature and time incubation. Thus, data shown here strengthen the usefulness of an easy, rapid, accessible and inexpensive approach to test protein flexibility related to its function.

19.
Behav Sci (Basel) ; 10(12)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321729

RESUMO

Life expectancy has increased in many countries throughout the world over recent years, leading to new challenges related to aging. A large part of the population is over 60 years old, and therefore studies that focus on financial autonomy and active aging are necessary. In this paper, we analyze the relationship between cognitive functioning and life satisfaction in relation to financial attitudes in a sample of 251 elderly adults (71% women) participating in an active aging program (M = 67.5, SD = 4.5). We used the Mini-Mental State Examination, the Satisfaction with Life scale, and a questionnaire about financial attitudes to gather data. Our results show that cognitive functioning and life satisfaction are related to certain financial attitudes. We also observed differences associated with gender, education level, and financial independence. According to our findings, life satisfaction should be taken into account when the financial attitudes of older adults are evaluated. The importance of support groups for the elderly is highlighted as well as of all those recreation and health programs, since they constitute a means of promoting well-being.

20.
J Forensic Sci ; 65(4): 1040-1048, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32176818

RESUMO

This systematic review deals with the last 10 years of research in analytical methodologies for the analysis of fingerprints, regarding their chemical and biological constituents. A total of 123 manuscripts, which fit the search criteria defined using the descriptor "latent fingermarks analysis," were selected. Its main instrumental areas (mass spectrometry, spectroscopy, and innovative methods) were analyzed and summarized in a specific table, highlighting its main analytical parameters. The results show that most studies in this field use mass spectrometry to identify the constituents of fingerprints, both to determine the chemical profile and for aging. There is also a marked use of mass spectrometry coupled with chromatographic methods, and it provides accurate results for a fatty acid profile. Additional significant results are achieved by spectroscopic methods, mainly Raman and infrared. It is noteworthy that spectroscopic methods using microscopy assist in the accuracy of the analyzed region of the fingerprint, contributing to more robust results. There was also a significant increase in studies using methods focused on finding new developers or identifying components present in fingerprints by rapid tests. This systematic review of analytical techniques applied to the detection of fingerprints explores different approaches to contribute to future studies in forensic identification, verifying new demands in the forensic sciences and assisting in the selection of studies for the progress of research.


Assuntos
Dermatoglifia , Ciências Forenses/métodos , Cromatografia , Ácidos Graxos/química , Humanos , Imunoensaio , Lipídeos/química , Espectrometria de Massas , Nanopartículas , Análise Espectral , Fatores de Tempo
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