RESUMEN
Lipids perform a series of cellular functions, establishing cell and organelles' boundaries, organizing signaling platforms, and creating compartments where specific reactions occur. Moreover, lipids store energy and act as secondary messengers whose distribution is tightly regulated. Disruption of lipid metabolism is associated with many diseases, including those caused by viruses. In this scenario, lipids can favor virus replication and are not solely used as pathogens' energy source. In contrast, cells can counteract viruses using lipids as weapons. In this review, we discuss the available data on how coronaviruses profit from cellular lipid compartments and why targeting lipid metabolism may be a powerful strategy to fight these cellular parasites. We also provide a formidable collection of data on the pharmacological approaches targeting lipid metabolism to impair and treat coronavirus infection.
Asunto(s)
Infecciones por Coronavirus , Coronavirus , Humanos , Metabolismo de los Lípidos , Infecciones por Coronavirus/tratamiento farmacológico , Replicación Viral , LípidosRESUMEN
Lipid droplets (LD) are evolutionarily conserved lipid-enriched organelles with a diverse array of cell- and stimulus-regulated proteins. Accumulating evidence demonstrates that intracellular pathogens exploit LD as energy sources, replication sites, and part of the mechanisms of immune evasion. Nevertheless, LD can also favor the host as part of the immune and inflammatory response to pathogens. The functions of LD in the central nervous system have gained great interest due to their presence in various cell types in the brain and for their suggested involvement in neurodevelopment and neurodegenerative diseases. Only recently have the roles of LD in neuroinfections begun to be explored. Recent findings reveal that lipid remodelling and increased LD biogenesis play important roles for Zika virus (ZIKV) replication and pathogenesis in neural cells. Moreover, blocking LD formation by targeting DGAT-1 in vivo inhibited virus replication and inflammation in the brain. Therefore, targeting lipid metabolism and LD biogenesis may represent potential strategies for anti-ZIKV treatment development. Here, we review the progress in understanding LD functions in the central nervous system in the context of the host response to Zika infection.
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Infecciones del Sistema Nervioso Central , Gotas Lipídicas , Infección por el Virus Zika , Virus Zika , Humanos , Gotas Lipídicas/metabolismo , Gotas Lipídicas/fisiología , Gotas Lipídicas/virología , Lípidos/fisiología , Replicación Viral/fisiología , Virus Zika/fisiología , Infección por el Virus Zika/fisiopatología , Infección por el Virus Zika/virología , Infecciones del Sistema Nervioso Central/fisiopatología , Infecciones del Sistema Nervioso Central/virologíaRESUMEN
The objective of this study was to observe patients' satisfaction with their in-service direct anterior dental restorations and to compare it with clinical evaluation using FDI (Federation Dental International) criteria. Patients scored their own anterior dental restorations regarding satisfaction (satisfactory /dissatisfactory). If dissatisfaction was mentioned, then, they would be interviewed about the complaint. In the same session, the dental restorations were clinically evaluated by two dentists using FDI criteria (1-5 score) concerning esthetic, functional, and biological domains. Descriptive statistics were used for frequencies of scores attributed by patients and clinicians. In order to compare patients' to clinicians' frequencies, the Chi-square test was applied (p ≤ 0.05). A total of 106 restorations were evaluated by patients and clinicians. Patients reported 52.8% of restorations satisfactory and 47.8% dissatisfactory. Overall, clinicians reported the same restorations as 82,3% satisfactory and 17,6% dissatisfactory. Patients' most frequent complaints referred to color, followed by anatomical form, fracture of material and retention, and approximal anatomical form. Comparing patients' satisfaction and dissatisfaction rates to clinicians' evaluation per criteria, there was no difference regarding esthetics. The frequency of dissatisfactory restorations by clinicians was significantly lower when functional and biological properties were compared with patients' opinions. Direct anterior dental restorations were more frequently reported as satisfactory by patients and clinicians, being the main complaints related to esthetic issues. When clinicians and patients' evaluations were compared, it was observed that the frequencies of satisfactory restoration by patients and clinicians were similar regarding esthetic properties, and significantly different regarding functional and biological properties.
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Estética Dental , Satisfacción del Paciente , Humanos , Restauración Dental Permanente , Fracaso de la Restauración Dental , Resinas CompuestasRESUMEN
Abstract The objective of this study was to observe patients' satisfaction with their in-service direct anterior dental restorations and to compare it with clinical evaluation using FDI (Federation Dental International) criteria. Patients scored their own anterior dental restorations regarding satisfaction (satisfactory /dissatisfactory). If dissatisfaction was mentioned, then, they would be interviewed about the complaint. In the same session, the dental restorations were clinically evaluated by two dentists using FDI criteria (1-5 score) concerning esthetic, functional, and biological domains. Descriptive statistics were used for frequencies of scores attributed by patients and clinicians. In order to compare patients' to clinicians' frequencies, the Chi-square test was applied (p ≤ 0.05). A total of 106 restorations were evaluated by patients and clinicians. Patients reported 52.8% of restorations satisfactory and 47.8% dissatisfactory. Overall, clinicians reported the same restorations as 82,3% satisfactory and 17,6% dissatisfactory. Patients' most frequent complaints referred to color, followed by anatomical form, fracture of material and retention, and approximal anatomical form. Comparing patients' satisfaction and dissatisfaction rates to clinicians' evaluation per criteria, there was no difference regarding esthetics. The frequency of dissatisfactory restorations by clinicians was significantly lower when functional and biological properties were compared with patients' opinions. Direct anterior dental restorations were more frequently reported as satisfactory by patients and clinicians, being the main complaints related to esthetic issues. When clinicians and patients' evaluations were compared, it was observed that the frequencies of satisfactory restoration by patients and clinicians were similar regarding esthetic properties, and significantly different regarding functional and biological properties.
Resumo O objetivo deste estudo foi observar a satisfação dos pacientes com suas restaurações dentárias anteriores diretas e compará-las com a avaliação clínica do dentista usando os critérios FDI (Federation Dental International). Os pacientes pontuaram suas restaurações dentárias (n=106) anteriores em relação à satisfação (satisfatória / insatisfatória). Quando insatisfatória, ele foi entrevistado sobre a queixa. Na mesma sessão, as restaurações dentárias foram avaliadas clinicamente por dois dentistas utilizando os critérios FDI (escore 1-5) quanto aos aspectos estéticos, funcionais e biológicos. Estatística descritiva foi usada para frequências de escores atribuídos por pacientes e clínicos. Para comparar as frequências dos pacientes e dos clínicos, foi aplicado o teste Qui-quadrado (p ≤ 0,05). Os pacientes relataram suas restaurações como 52,8% satisfatórias e 47,8% insatisfatórias. Os clínicos reportaram as mesmas restaurações, 82,3% satisfatória e 17,6% insatisfatória. As queixas mais frequentes dos pacientes referiam-se à cor, seguida da forma anatômica, fratura e retenção do material e forma anatômica proximal. Comparando os índices de satisfação e insatisfação dos pacientes com os clínicos, não houve diferença em relação à estética. A frequência de restaurações insatisfatórias por dentistas foi significativamente menor quando as propriedades funcionais e biológicas foram comparadas com as opiniões dos pacientes. As restaurações foram mais frequentemente relatadas como satisfatórias pelos pacientes, sendo as principais queixas relacionadas a questões estéticas. Quando as avaliações dos clínicos e dos pacientes foram comparadas, observou-se que as frequências de restaurações satisfatórias por pacientes e clínicos foram semelhantes em relação às propriedades estéticas e significativamente diferentes em relação às propriedades funcionais e biológicas.
RESUMEN
Zika virus (ZIKV) infection is a global public health concern linked to adult neurological disorders and congenital diseases in newborns. Host lipid metabolism, including lipid droplet (LD) biogenesis, has been associated with viral replication and pathogenesis of different viruses. However, the mechanisms of LD formation and their roles in ZIKV infection in neural cells are still unclear. Here, we demonstrate that ZIKV regulates the expression of pathways associated with lipid metabolism, including the upregulation and activation of lipogenesis-associated transcription factors and decreased expression of lipolysis-associated proteins, leading to significant LD accumulation in human neuroblastoma SH-SY5Y cells and in neural stem cells (NSCs). Pharmacological inhibition of DGAT-1 decreased LD accumulation and ZIKV replication in vitro in human cells and in an in vivo mouse model of infection. In accordance with the role of LDs in the regulation of inflammation and innate immunity, we show that blocking LD formation has major roles in inflammatory cytokine production in the brain. Moreover, we observed that inhibition of DGAT-1 inhibited the weight loss and mortality induced by ZIKV infection in vivo. Our results reveal that LD biogenesis triggered by ZIKV infection is a crucial step for ZIKV replication and pathogenesis in neural cells. Therefore, targeting lipid metabolism and LD biogenesis may represent potential strategies for anti-ZIKV treatment development.
Asunto(s)
Neuroblastoma , Infección por el Virus Zika , Virus Zika , Animales , Humanos , Ratones , Gotas Lipídicas , Replicación ViralRESUMEN
Lipid droplets (LD) are evolutionarily conserved lipid-enriched organelles with a diverse array of cell- and stimulus-regulated proteins. Accumulating evidence demonstrates that intracellular pathogens exploit LD as energy sources, replication sites, and part of the mechanisms of immune evasion. Nevertheless, LD can also favor the host as part of the immune and inflammatory response to pathogens. The functions of LD in the central nervous system have gained great interest due to their presence in various cell types in the brain and for their suggested involvement in neurodevelopment and neurodegenerative diseases. Only recently have the roles of LD in neuroinfections begun to be explored. Recent findings reveal that lipid remodelling and increased LD biogenesis play important roles for Zika virus (ZIKV) replication and pathogenesis in neural cells. Moreover, blocking LD formation by targeting DGAT-1 in vivo inhibited virus replication and inflammation in the brain. Therefore, targeting lipid metabolism and LD biogenesis may represent potential strategies for anti-ZIKV treatment development. Here, we review the progress in understanding LD functions in the central nervous system in the context of the host response to Zika infection.
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This review aims to describe and discuss the different functions of the endolysosomal system, from homeostasis to its vital role during viral infections. We will initially describe endolysosomal system's main functions, presenting recent data on how its compartments are essential for host defense to explore later how SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) and other coronaviruses subvert these organelles for their benefit. It is clear that to succeed, pathogens' evolution favored the establishment of ways to avoid, escape, or manipulate lysosomal function. The unavoidable coexistence with such an unfriendly milieu imposed on viruses the establishment of a vast array of strategies to make the most out of the invaded cell's machinery to produce new viruses and maneuvers to escape the host's defense system.
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COVID-19 , SARS-CoV-2 , Endosomas , Humanos , LisosomasRESUMEN
Coronavirus disease 2019 (COVID-19) is currently a worldwide emergency caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). In observational clinical studies, statins have been identified as beneficial to hospitalized patients with COVID-19. However, experimental evidence of underlying statins protection against SARS-CoV-2 remains elusive. Here we reported for the first-time experimental evidence of the protective effects of simvastatin treatment both in vitro and in vivo. We found that treatment with simvastatin significantly reduced the viral replication and lung damage in vivo, delaying SARS-CoV-2-associated physiopathology and mortality in the K18-hACE2-transgenic mice model. Moreover, simvastatin also downregulated the inflammation triggered by SARS-CoV-2 infection in pulmonary tissue and in human neutrophils, peripheral blood monocytes, and lung epithelial Calu-3 cells in vitro, showing its potential to modulate the inflammatory response both at the site of infection and systemically. Additionally, we also observed that simvastatin affected the course of SARS-CoV-2 infection through displacing ACE2 on cell membrane lipid rafts. In conclusion, our results show that simvastatin exhibits early protective effects on SARS-CoV-2 infection by inhibiting virus cell entry and inflammatory cytokine production, through mechanisms at least in part dependent on lipid rafts disruption.
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Tratamiento Farmacológico de COVID-19 , Regulación hacia Abajo/efectos de los fármacos , Inflamación/tratamiento farmacológico , Microdominios de Membrana/efectos de los fármacos , SARS-CoV-2/patogenicidad , Simvastatina/farmacología , Animales , COVID-19/virología , Modelos Animales de Enfermedad , Humanos , Inflamación/virología , Pulmón/virología , Ratones , Ratones Transgénicos , Replicación Viral/efectos de los fármacosRESUMEN
Candidemia is a major complication in hematopoietic cell transplantation (HCT), and antifungal prophylaxis with fluconazole decreases the incidence of this complication. We compared 2 strategies for fluconazole prophylaxis in patients with hematologic malignancy undergoing autologous HCT between 1997 and 2017. From 1997 to 2003, fluconazole prophylaxis (400 mg/d) was given to all HCTs, started with the conditioning regimen (early prophylaxis), and given until neutrophil engraftment or the need of non-prophylactic antifungal therapy. From 2004 on, fluconazole (400mg daily) was started only if (and when) the patient developed oral mucositis (late prophylaxis). Among 571 HCT, 270 received early prophylaxis, 112 received late prophylaxis, and 189 did not receive fluconazole because they did not develop oral mucositis. The incidence of candidemia was 1.8% in the early prophylaxis group, 0% in the late prophylaxis group, and 1.1% in the no prophylaxis group (P = .31). Among patients receiving fluconazole, the median duration of prophylaxis was 17 days (range, 6-36 days) in the early prophylaxis group and 6 days (range, 2-16 days) in the late prophylaxis group (P < .001). The initiation of fluconazole prophylaxis guided by the occurrence of oral mucositis (late prophylaxis) was as good as early fluconazole prophylaxis.
Asunto(s)
Fluconazol , Trasplante de Células Madre Hematopoyéticas , Antifúngicos/uso terapéutico , Fluconazol/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Acondicionamiento Pretrasplante , Trasplante AutólogoRESUMEN
O exame clínico, a sondagem periodontal e a radiografia são os três principais métodos de avaliação de saúde oral usados pelo cirurgião-dentista. Com isso, foi elaborado uma Revisão de Literatura com pesquisa no banco de dados da PubMed, Wiley Online Library e Google Acadêmico, com lapso temporal de 1998 a 2021, com o objetivo de avaliar a aplicação da TCO como possível método auxiliar no diagnóstico de doença periodontal. A partir de 1998, a TCO passa a ser estudada como possível método de diagnóstico não invasivo na Odontologia. Entre os benefícios referentes à Periodontia, tem sido relatado: a possibilidade de visualizar estruturas importantes do periodonto, fazer sondagem periodontal, diferenciar fenótipo gengival, detectar presença de cálculo supra e subgengival, além da observação de microestrutura e vascularização gengival, auxiliando no diagnóstico e acompanhamento do tratamento periodontal. Portando, a TCO é uma tecnologia emergente de bio-imagem que gera imagens estruturais bi e tridimensionais em alta resolução dos tecidos duros e moles do periodonto. Entretanto, mais estudos são necessários para superar as limitações da técnica e desenvolver sistemas de baixo custo para impulsionar seu uso em ambiente clínico... (AU)
Physical examination, periodontal probing and radiography are the three main methods of assessing oral health used by the dentist. Thereby, a Literature review was prepared based on research in the database of PubMed, Wiley Online Library and Google Academic, with time lapse from 1998 to 2021, with the objective of evaluating the application of OCT as a possible auxiliary method in the diagnosis of periodontal disease. Since 1998, the OCT has been studied as a possible non-invasive diagnostic method in Dentistry. Among the benefits related to Periodontics, it has been reported: the possibility of viewing important structures of the periodontium, periodontal probing, differentiating gingival phenotype, detecting the presence of supra and subgingival calculus, in addition to the observation of gingival microstructure and vascularization, helping in the diagnosis and monitoring of periodontal treatment. Therefore, the OCT is an emerging bio-imaging technology that generates high resolution bi and three-dimensional structural images of the hard and soft tissues of the periodontium. However, further studies are needed to overcome the limitations of the technique and develop low-cost systems to boost its use in a clinical setting... (AU)
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Humanos , Periodoncia , Diagnóstico por Imagen , Odontología , Tomografía de Coherencia Óptica , Enfermedades Periodontales , Examen Físico , Salud Bucal , Odontólogos , Diagnóstico BucalRESUMEN
PURPOSE: To compare direct clinical and indirect digital photographic assessment of resin composite restorations. Ninety-two posterior resin composite restorations were classified using World Dental Federation (FDI) criteria by two different clinical examiners (C1 and C2). In the same appointment of clinical assessment, intraoral high-quality digital photographs were taken and posteriorly two different digital examiners (D1 and D2) classified the images of each restoration. Restorations of each patient were assessed once by C1 and C2 independently. D1 and D2 assessed the digital images from different locations and in different time. Data were analyzed using the Cohen's kappa coefficient, Kruskal-Wallis non-parametric test and Dunn's multiple shared test, with 95% confidence. Agreement levels varied from very good (0.81-1.00) to fair (0.21-0.40). Statistically significant differences (p < 0.05) between assessments were found for surface lustre, staining, color match and translucency, esthetic anatomical form, fracture of material and retention and marginal adaptation. The classification of the resin composite restorations varied significantly according to clinical or high-quality digital photographic assessments. Overall, clinical assessment detected more demand for repair or replacement.
Asunto(s)
Adaptación Marginal Dental , Restauración Dental Permanente , Color , Resinas Compuestas , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Fotograbar , Propiedades de SuperficieRESUMEN
Leptin is a pleiotropic adipokine that regulates immunometabolism centrally and peripherally. Obese individuals present increased levels of leptin in the blood and develop hypothalamic resistance to this adipokine. Here we investigated whether leptin effects on the periphery are maintained despite the hypothalamic resistance. We previously reported that leptin injection induces in vivo neutrophil migration and peritoneal macrophage activation in lean mice through TNF-α- and CXCL1-dependent mechanisms. However, leptin effects on leukocyte biology during obesity remain unclear. In this study, we investigated the in vivo responsiveness of leukocytes to i.p. injected leptin in mice with diet-induced obesity (DIO). After 14-16 wk, high-sucrose, high-fat diet (HFD)-fed mice showed hyperglycemia, hyperleptinemia, and dyslipidemia compared to normal-sucrose, normal-fat diet (ND). Exogenous leptin did not reduce food intake in DIO mice in contrast to control mice, indicating that DIO mice were centrally resistant to leptin. Regardless of the diet, we found increased levels of TNF-α and CXCL1 in the animals injected with leptin, alongside a pronounced neutrophil migration to the peritoneal cavity and enhanced biogenesis of lipid droplets in peritoneal macrophages. Supporting our in vivo results, data from ex vivo leptin stimulation experiments confirmed hypothalamic resistance in DIO mice, whereas bone marrow cells responded to leptin stimulation through mTOR signaling despite obesity. Altogether, our results show that leukocytes responded equally to leptin in ND- or HFD-fed mice. These results support a role for leptin in the innate immune response also in obesity, contributing to the inflammatory status that leads to the development of metabolic disease.
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Inmunidad Innata , Leptina/metabolismo , Obesidad/etiología , Obesidad/metabolismo , Transducción de Señal , Animales , Biomarcadores , Citocinas/metabolismo , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Leucocitos/inmunología , Leucocitos/metabolismo , RatonesRESUMEN
A set of attributes endows the soils with distinctive characteristics and astute understanding is required in order to formulate suitable strategies for soil management. The aim of this study was to physically, chemically and mineralogically characterize samples of the main soil classes in Minas Gerais, Brazil, determine the point of zero salt effect (PZSE) and the point of zero charge (PZC), and ascertain the correlation between these factors and soil attributes. The soils evaluated presented different textural classes ranging from loamy sand (Entisol) to very clayey (some Oxisols and Ultisols). The soils differed substantially in terms of fertility, presenting a range from dystrophic (low fertility, base saturation < 50 %) to eutrophic character (fertility, base saturation >= 50 %), even within the same soil class, such as the Oxisols, which suggests the concurrence of the parent material. Highly weathered soils are predominant in Minas Gerais and these soils are composed predominantly of kaolinite, gibbsite, goethite and hematite. Traces of hydroxy-Al interlayered vermiculite and illite were also found in the Oxisols, Ultisols and Inceptisols. A correlation between the PZSE and the PZC in the A horizon was observed. A high degree of correlation was observed between the PZC and the exchangeable aluminum and the ratio of iron obtained by ammonium oxalate and dithionite-citrate (Feo/Fed) in both the A and B horizons of soil classes. The results obtained reinforce the importance of knowledge of soil attributes to the adoption of practices such as the management of phosphate fertilization in clayey soils and liming in soils rich in aluminum.(AU)
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Suelo/química , Suelos Arcillosos/análisis , Minerales/análisisRESUMEN
Arsenic (As) is a naturally occurring chemical element considered toxic and carcinogenic by health and environmental protection agencies. Studies of As adsorption/desorption behavior in soils are important to predictions of As potential mobility in natural systems. The aim of this study was to assess the adsorption of As(V) in soils from Minas Gerais, Brazil, and determine its immobilization rate in order to identify soils with characteristics more favorable to its deployment as an As geochemical barrier. The adsorption experiment was performed using different As concentrations and the data pertaining to the maximum adsorption capacity of As(V) (MACAs) were determined by Langmuir and Freundlich isoterms. The Oxisols, due to their more oxidic mineralogy, especially more gibbsitic, and clayey texture, showed the highest MACAs, followed by Ultisols, Inceptisols, and Entisols. In terms of the desorption of As the Inceptisols were the soils that showed the most As desorption. Both As desorption and mobility was lower in the more oxidic and clayey soils. In all soils, the total amount of As was desorbed in due course, but the As release ratio tended to decrease with the passage of time. In general, soils with higher MACAs did not necessarily show less As desorption. For use as a geochemical barrier, as important as a high adsorption capacity of As by the soil is a low As desorption rate. The increase in As mobility may increase the risks of contaminating the supplies of water. To be a good As geochemical barrier the soil has to be a clayey Oxisol, with relatively high amounts of Fe and Al oxides, especially gibbsite.(AU)
Asunto(s)
Arsénico/análisis , Arsénico/química , Química del Suelo , Adsorción , Contaminantes AmbientalesRESUMEN
Arsenic (As) is a naturally occurring chemical element considered toxic and carcinogenic by health and environmental protection agencies. Studies of As adsorption/desorption behavior in soils are important to predictions of As potential mobility in natural systems. The aim of this study was to assess the adsorption of As(V) in soils from Minas Gerais, Brazil, and determine its immobilization rate in order to identify soils with characteristics more favorable to its deployment as an As geochemical barrier. The adsorption experiment was performed using different As concentrations and the data pertaining to the maximum adsorption capacity of As(V) (MACAs) were determined by Langmuir and Freundlich isoterms. The Oxisols, due to their more oxidic mineralogy, especially more gibbsitic, and clayey texture, showed the highest MACAs, followed by Ultisols, Inceptisols, and Entisols. In terms of the desorption of As the Inceptisols were the soils that showed the most As desorption. Both As desorption and mobility was lower in the more oxidic and clayey soils. In all soils, the total amount of As was desorbed in due course, but the As release ratio tended to decrease with the passage of time. In general, soils with higher MACAs did not necessarily show less As desorption. For use as a geochemical barrier, as important as a high adsorption capacity of As by the soil is a low As desorption rate. The increase in As mobility may increase the risks of contaminating the supplies of water. To be a good As geochemical barrier the soil has to be a clayey Oxisol, with relatively high amounts of Fe and Al oxides, especially gibbsite.
Asunto(s)
Adsorción , Arsénico/análisis , Arsénico/química , Química del Suelo , Contaminantes AmbientalesRESUMEN
A set of attributes endows the soils with distinctive characteristics and astute understanding is required in order to formulate suitable strategies for soil management. The aim of this study was to physically, chemically and mineralogically characterize samples of the main soil classes in Minas Gerais, Brazil, determine the point of zero salt effect (PZSE) and the point of zero charge (PZC), and ascertain the correlation between these factors and soil attributes. The soils evaluated presented different textural classes ranging from loamy sand (Entisol) to very clayey (some Oxisols and Ultisols). The soils differed substantially in terms of fertility, presenting a range from dystrophic (low fertility, base saturation = 50 %), even within the same soil class, such as the Oxisols, which suggests the concurrence of the parent material. Highly weathered soils are predominant in Minas Gerais and these soils are composed predominantly of kaolinite, gibbsite, goethite and hematite. Traces of hydroxy-Al interlayered vermiculite and illite were also found in the Oxisols, Ultisols and Inceptisols. A correlation between the PZSE and the PZC in the A horizon was observed. A high degree of correlation was observed between the PZC and the exchangeable aluminum and the ratio of iron obtained by ammonium oxalate and dithionite-citrate (Feo/Fed) in both the A and B horizons of soil classes. The results obtained reinforce the importance of knowledge of soil attributes to the adoption of practices such as the management of phosphate fertilization in clayey soils and liming in soils rich in aluminum.
Asunto(s)
Minerales/análisis , Suelo/química , Suelos Arcillosos/análisisRESUMEN
OBJECTIVE: To evaluate the clinical performance of posterior resin composite restorations regarding experimental and regular adhesive protocols in caries affected-dentin (CAD). MATERIAL AND METHODS: A total of 92 class I and class II cavities with carious lesions were selected and randomly assigned to the following groups: (1) bioactive glass-ceramic powder/two-step etch and rinse system, (2) control/two-step etch and rinse system, (3) bioactive glass-ceramic powder/two-step self-etching system, and (4) control/two-step self-etching system. Two operators carried out the adhesive protocols and restored the cavities with a nano-hybrid resin composite. Participants were followed up at 1 week and 6, 12, and 18 months for clinical evaluation performed by two blinded examiners and calibrated according to FDI criteria. Data were analyzed using Kruskal-Wallis and Dunn tests with a confidence of 95%. RESULTS: The clinical performance of resin composite restoration was not affected by the experimental use of an adhesive protocol including a bioactive glass-ceramic powder for 18 months post-procedure. However, there was a significant difference between group 2 and group 4 (p < 0.05) for marginal adaptation (18 months). Group 2 was significantly different from group 3 (p < 0.05) for fracture of material/retention (18 months) and marginal adaptation (1 week); group 2 showed a better performance. CONCLUSION: Adhesive protocols can alter the clinical performance of posterior restorations in terms of marginal adaptation and the fracture of material/retention in CAD. CLINICAL SIGNIFICANCE: Adhesive protocols may influence the success of resin composite restorations in CAD; this is important because failure can lead to caries, re-incidence, and/or clinical re-work.
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Recubrimiento Dental Adhesivo , Caries Dental/terapia , Restauración Dental Permanente , Dentina , Grabado Ácido Dental , Adolescente , Adulto , Cerámica , Resinas Compuestas , Cementos Dentales , Grabado Dental , Adaptación Marginal Dental , Recubrimientos Dentinarios , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polvos , Cementos de Resina , Adulto JovenRESUMEN
OBJECTIVE: The use of electronic cigarettes (ECIGs) has recently increased as an alternative to conventional smoking tobacco products. The literature is scarce on the effects of ECIGs on dental and oral structures. Therefore, the objective of this study was to observe whether ECIG aerosol could alter the color of dental enamel. MATERIALS AND METHODS: Sixty-three bovine enamel specimens were randomly separated into groups (n = 7) and treated with aerosols with different e-liquid flavors (neutral, menthol, and tobacco) and nicotine content (0, 12, and 18 mg). The initial color assessment was performed using a spectrophotometer (Easy Shade-Vita). Dental enamel was exposed to 20 cycles of ECIG aerosol in a smoking machine, and the final color was measured. The color change was evaluated using ΔEab, ΔE00, and Whiteness Index (WID ) formulae. Differences in L* a* b* coordinates were calculated, and data were analyzed (two-way ANOVA, uncorrected Fisher's LSD post hoc test, α = 0.05). RESULTS: Luminosity (ΔL) was reduced by aerosols with almost all levels of nicotine content and neutral and menthol flavors. Flavored e-liquids caused more color change (P < .05) according to ΔEab and ΔE00. ΔE values from both formulae exceeded the thresholds for perceptible visual alterations of color. WID increased after ECIGs exposure for menthol and tobacco and decreased for neutral flavors. CONCLUSIONS: ECIG aerosol from e-liquids with different nicotine contents and flavors altered enamel color. Menthol and tobacco e-liquids may alter the enamel color decreasing the yellowness of the enamel compared to neutral e-liquid. CLINICAL SIGNIFICANCE: Electronic cigarettes can cause perceptible changes in tooth color, altering dental esthetics.
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Sistemas Electrónicos de Liberación de Nicotina , Aerosoles , Animales , Bovinos , Color , Esmalte Dental , NicotinaRESUMEN
Background: Leptin is an adipokine with well-known effects on the central nervous system including the induction of energy expenditure and satiety. Leptin also has major relevance when activating immune cells and modulating inflammatory response. In obesity, increases in white adipose tissue accumulation and leptin levels are accompanied by hypothalamic resistance to leptin. Even though the adipose tissue is a leptin-rich environment, the local actions of leptin regarding adipogenesis were not thoroughly investigated until now. Here we evaluate the contributions of leptins direct signaling in preadipocytes and adipose tissue-derived stromal cells (ASCs) for adipogenesis. Methods: Adipocytes were differentiated from the murine lineage of preadipocytes 3T3-L1 or ASCs from subcutaneous and visceral (retroperitoneal) fat depots from C57Bl/6J mice. Differentiating cells were treated with leptin in addition to or in replacement of insulin. The advance of adipogenesis was assessed by the expression and secretion of adipogenesis- and lipogenesis-related proteins by Western blot and immunoenzimatic assays, and the accumulation of lipid droplets by fluorescence microscopy. Results: Leptin treatment in 3T3-L1 preadipocytes or ASCs increased the production of the adipogenesis- and lipogenesis-related proteins PLIN1, CAV-1, PPARγ, SREBP1C, and/or adiponectin at earlier stages of differentiation. In 3T3-L1 preadipocytes, we found that leptin induced lipid droplets' formation in an mTOR-dependent manner. Also, leptin induced a proinflammatory cytokine profile in 3T3-L1 and ASCs, modulating the production of TNF-α, IL-10, and IL-6. Since insulin is considered an essential factor for preadipocyte differentiation, we asked whether leptin would support adipogenesis in the absence of insulin. Importantly, leptin induced the formation of lipid droplets and the expression of adipogenesis-related proteins independently of insulin during the differentiation of 3T3-L1 cells and ASCs. Conclusions: Our results demonstrate that leptin induces intracellular signaling in preadipocytes and adipocytes promoting adipogenesis and modulating the secretion of inflammatory mediators. Also, leptin restores adipogenesis in the absence of insulin. These findings contribute to the understanding of the local signaling of leptin in precursor and mature adipose cells. The proadipogenic role of leptin unraveled here may be of especial relevance during obesity, when its central signaling is defective.
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BACKGROUND: Breastfeeding plays an important role in child health. However, there are doubts about its influence on malocclusions. Systematic reviews have yielded contradictory results. Research aim: This study aimed to investigate whether the type and duration of breastfeeding are associated with malocclusions in primary teething. METHODS: The review strategy included several electronic databases, lists of references, reviews, dissertation and thesis websites, experts, and other relevant documents. Published and unpublished observational studies ( N = 42) were reviewed using the Participants (children), Interventions (breastfeeding), Comparisons (bottle feeding), Outcomes (malocclusion), and Study design (observational) strategy, without restrictions on language or locale. Information about the authors, publication year, country of study, setting, study design, sample size, age, type and duration of exclusive and mixed breastfeeding, and malocclusions was recorded by two blinded evaluators. Quantitative meta-analysis ( N = 30) of the studies with available data was performed. RESULTS: Breastfeeding was a protective factor against malocclusions. The odds of association increased with breastfeeding duration. Irrespective of duration, breastfeeding had a protective association with open bite. For those who were breastfed for up to 6 months, breastfeeding protected against overjet, open bite, posterior crossbite, and crowding. Breastfeeding for 12 months or longer was associated with lower odds of overjet, open bite, and posterior crossbite. Breastfeeding exclusively for 6 months was also a protective factor against malocclusions. However, studies on this subject presented low quality, statistical heterogeneity, and only unadjusted measures of association in most of the cases. CONCLUSION: Breastfeeding beneficially affects primary occlusion when practiced for at least 6 months.