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1.
J Biomed Sci ; 31(1): 48, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730462

RESUMO

Retinal degenerative diseases, including diabetic retinopathy (DR) and age-related macular degeneration (AMD), loom as threats to vision, causing detrimental effects on the structure and function of the retina. Central to understanding these diseases, is the compromised state of the blood-retinal barrier (BRB), an effective barrier that regulates the influx of immune and inflammatory components. Whether BRB breakdown initiates retinal distress, or is a consequence of disease progression, remains enigmatic. Nevertheless, it is an indication of retinal dysfunction and potential vision loss.The intricate intercellular dialogues among retinal cell populations remain unintelligible in the complex retinal milieu, under conditions of inflammation and oxidative stress. The retina, a specialized neural tissue, sustains a ceaseless demand for oxygen and nutrients from two vascular networks. The BRB orchestrates the exchange of molecules and fluids within this specialized region, comprising the inner BRB (iBRB) and the outer BRB (oBRB). Extracellular vesicles (EVs) are small membranous structures, and act as messengers facilitating intercellular communication in this milieu.EVs, both from retinal and peripheral immune cells, increase complexity to BRB dysfunction in DR and AMD. Laden with bioactive cargoes, these EVs can modulate the retinal microenvironment, influencing disease progression. Our review delves into the multifaceted role of EVs in retinal degenerative diseases, elucidating the molecular crosstalk they orchestrate, and their microRNA (miRNA) content. By shedding light on these nanoscale messengers, from their biogenesis, release, to interaction and uptake by target cells, we aim to deepen the comprehension of BRB dysfunction and explore their therapeutic potential, therefore increasing our understanding of DR and AMD pathophysiology.


Assuntos
Barreira Hematorretiniana , Vesículas Extracelulares , Barreira Hematorretiniana/metabolismo , Barreira Hematorretiniana/fisiopatologia , Vesículas Extracelulares/metabolismo , Humanos , Retinopatia Diabética/fisiopatologia , Retinopatia Diabética/metabolismo , Doenças Retinianas/fisiopatologia , Doenças Retinianas/metabolismo , Degeneração Macular/fisiopatologia , Degeneração Macular/metabolismo , Animais
2.
Lasers Med Sci ; 39(1): 21, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165503

RESUMO

This in vitro experimental investigation aimed to evaluate the impact of the combined application of a nanofiber scaffold (NS), a polymeric catalyst primer (PCP) containing 10 mg/mL of heme peroxidase enzyme, and violet LED (LEDv) on the esthetic efficacy (EE), trans-amelodentinal cytotoxicity (TC), and procedural duration of conventional in-office bleaching therapy. To achieve this, 96 standardized enamel/dentin discs were individually placed in artificial pulp chambers. A 35% hydrogen peroxide (H2O2) bleaching gel was administered for 45, 30, or 15 min to the enamel, either previously coated with NS + PCP or left uncoated, followed by irradiation with LEDv for 15 min or no irradiation. The established groups were as follows: G1, negative control (no treatment); G2, 35% H2O2/45 min; G3, NS + PCP + LEDv; G4, NS + PCP + 35%H2O2/45 min + LEDv; G5, NS + PCP + 35%H2O2/30 min + LEDv; and G6, NS + PCP + 35%H2O2/15 min + LEDv. Extracts (culture medium + gel components diffused through the discs) were collected and applied to odontoblast-like MDPC-23 cells. EE (ΔE00 and ΔWI) and TC were assessed using ANOVA/Tukey analysis (p < 0.05). The EE analysis revealed no statistical differences between G6 and G2 (p > 0.05). Cells in G6 exhibited higher viability and lower oxidative stress compared to other bleached groups (p < 0.05). In conclusion, employing NS + PCP + LEDv to catalyze a 35%H2O2 bleaching gel applied for 15 min to the enamel resulted in successful esthetic improvements and reduced the cytotoxicity commonly linked with traditional in-office bleaching procedures.


Assuntos
Peróxido de Hidrogênio , Polímeros , Peróxido de Hidrogênio/farmacologia , Biopolímeros , Catálise , Meios de Cultura
3.
J Exp Biol ; 226(13)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37326253

RESUMO

Seabirds have evolved several life-history characteristics to help buffer environmental stochasticity. However, particularly during the breeding season, seabirds may be affected by reductions in prey availability and localised oceanographic conditions caused by variations in the environment. The increase in sea surface temperature, triggered by accelerated global warming, is impairing phytoplankton production of omega-3 fatty acids (FAs). Here, we assessed the ecological role of omega-3 FAs on chick development and subsequently on breeder foraging behaviour in two closely related shearwater species foraging in contrasting marine environments. We supplemented chicks with omega-3 FA pills or with control placebo pills and monitored chick growth, chick health status and breeder at-sea foraging behaviour using global positioning system devices. We found that omega-3 chick supplementation reduced the 95% kernel utilization distribution of short trips of Cape Verde shearwaters, but overall, breeders kept a similar foraging pattern between treatments, potentially influenced by predictable prey patches off the West African coast. In contrast, for Cory's shearwaters, the parents of the omega-3 group greatly reduced the foraging effort. This suggests that the proximity to productive prey patches around the colony may help birds to adjust their effort and, therefore, energy expenditure, to changes in the development of their offspring, as driven by their nutritional status. Overall, our results suggest a link between a chick diet enriched in omega-3 FAs and parental foraging effort, providing insight into their ability to cope with a changing and increasingly stochastic marine environment.


Assuntos
Galinhas , Dieta , Animais , Dieta/veterinária , Suplementos Nutricionais , Comportamento Alimentar , Estado Nutricional
4.
Adv Exp Med Biol ; 1415: 21-26, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440009

RESUMO

Matrix metalloproteinases (MMPs) are a tightly regulated family of proteolytic enzymes that break down extracellular matrix (ECM) and basement membrane components. Because it is associated with development, morphogenesis, tissue remodeling, and repair, ECM remodeling is an important mechanism. MMPs are thought to act as a double-edged sword, as they contribute to maintaining photoreceptors/retinal pigment epithelium (RPE)/Bruch's membrane (BM)/choroid complex homeostasis and also contribute to the onset and progression of age-related macular degeneration (AMD). Polymorphisms and/or altered expression in MMPs and their tissue inhibitors (TIMPs) are associated with age-related macular degeneration (AMD). Here, we review the evidence for MMPs' role in the onset and progression of AMD via addressing their regulation and TIMPs' significant regulatory functions.


Assuntos
Degeneração Macular , Humanos , Degeneração Macular/genética , Degeneração Macular/metabolismo , Lâmina Basilar da Corioide/metabolismo , Corioide , Epitélio Pigmentado da Retina/metabolismo , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo
5.
Mycopathologia ; 188(5): 815-819, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37458853

RESUMO

Direct microscopic examination of samples using potassium hydroxide (KOH) is a fast, simple, and inexpensive method to confirm clinical suspicion of superficial mycosis. However, the lack of color contrast in this test makes it difficult to separate any fungal structures from artifacts. The sensitivity of the KOH mount technique may be enhanced using both fluorochromes and conventional stains that highlight the fungal structures when observed under fluorescence microscopy and bright-field, respectively. Here we study the possibility of using Trypan Blue (TB), an azo dye which is often used as a live/dead marker, in the diagnosis of superficial mycoses by KOH testing. TB at 0.01% displayed a fluorescent staining pattern similar to that of Calcofluor White (CFW), the conventional cell wall fluorophore. Furthermore, by adjusting the TB concentration to 0.1-0.3%, in addition to maintaining the fluorescent staining pattern, the fungal elements were stained in blue under bright-field microscopy. Thus, we demonstrate for the first time that TB has the unique property as a fungal stain that can be used in both bright-field and fluorescence microscopy for diagnosis of superficial mycoses by direct microscopic examination.

6.
Int J Mol Sci ; 24(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37372968

RESUMO

Diabetes is a prevalent global health issue associated with significant morbidity and mortality. Diabetic retinopathy (DR) is a well-known inflammatory, neurovascular complication of diabetes and a leading cause of preventable blindness in developed countries among working-age adults. However, the ocular surface components of diabetic eyes are also at risk of damage due to uncontrolled diabetes, which is often overlooked. Inflammatory changes in the corneas of diabetic patients indicate that inflammation plays a significant role in diabetic complications, much like in DR. The eye's immune privilege restricts immune and inflammatory responses, and the cornea and retina have a complex network of innate immune cells that maintain immune homeostasis. Nevertheless, low-grade inflammation in diabetes contributes to immune dysregulation. This article aims to provide an overview and discussion of how diabetes affects the ocular immune system's main components, immune-competent cells, and inflammatory mediators. By understanding these effects, potential interventions and treatments may be developed to improve the ocular health of diabetic patients.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Retina , Inflamação , Retinopatia Diabética/etiologia , Face
7.
J Esthet Restor Dent ; 35(2): 406-415, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36193855

RESUMO

OBJECTIVE: Evaluate the influence of a polymeric catalyst primer (PCP) on esthetic efficacy (EE), degradation kinetics of hydrogen peroxide (H2 O2 ), and trans-amelodentinal cytotoxicity (TC) of bleaching gels. MATERIALS AND METHODS: The following groups were established: G1: No treatment (NC, negative control); G2: PCP; G3: 10% H2 O2 ; G4: PCP + 10% H2 O2 ; G5: 20% H2 O2 ; G6: PCP + 20% H2 O2 ; G7: 35% H2 O2 (positive control); G8: PCP + 35% H2 O2 . To determine EE, enamel/dentin discs (E/DDs) were stained and subjected or not to bleaching protocols for 45 min. To assess TC, the E/DDs were adapted to artificial pulp chambers. The extracts (culture medium + gel components diffused through E/DDs) were applied to odontoblast-like MDPC-23 cells. The viability (VB), oxidative stress (OxS), morphology (SEM), amount of H2 O2 diffused and the production of hydroxyl radical (OH• ) were assessed (two-way ANOVA/Tukey/paired Student t-test; p < 0.05). RESULTS: The highest EE was found in G8 (p < 0.05), and G4, G6, and G7 did not differ statistically (p > 0.05). In G4, the limited H2 O2 diffusion reduced OxS and increased cell VB (p < 0.05). CONCLUSIONS: Coating the enamel with PCP containing 10 mg/ml of manganese oxide before applying the 10% H2 O2 bleaching gel maintains the EE of conventional in-office bleaching and minimizes the toxic effects of this esthetic therapy. CLINICAL SIGNIFICANCE: Coating the enamel with a PCP before applying the bleaching gel may potentiate the EE of the conventional in-office tooth bleaching and reduce the toxicity of this professional therapy to the dental pulp.


Assuntos
Clareadores Dentários , Clareamento Dental , Humanos , Clareamento Dental/métodos , Peróxido de Hidrogênio/farmacologia , Clareadores Dentários/farmacologia , Odontoblastos , Esmalte Dentário
8.
Ann Vasc Surg ; 87: 402-410, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35772668

RESUMO

BACKGROUND: Graft infections are one of the most serious complications in vascular surgery, with high mortality rates. Few studies addressed risk factors associated with a higher susceptibility to infection. The aim of this study is to identify perioperative factors associated with aortic graft infections (AGI). METHODS: We designed a retrospective, case-control study from patients subjected to open aortic repair between 2013 and 2019. Cases of AGI were defined according to the management of aortic graft infection collaboration (MAGIC) criteria and matched to controls without proven infection. Demographics, hospital complications, and laboratory workups were assessed. Predictors of AGI were identified through univariate and multivariate analysis. RESULTS: Most graft infections occurred in a late period (n = 17; 85%), after a median interval of 13.5 months interquartile range (IQR 1.5-36). Gram-negative bacteria were most frequently isolated in infected grafts, namely Enterobacteriaceae (n = 12). Cases had significantly lower postoperative serum albumin levels (1.9 g/dL vs. 2.4 g/dL; P = 0.002). Alcohol abuse, malignancy, prolonged lengths of stay, wound infection and dehiscence, in-hospital infection, postoperative heart failure or bowel ischemia were significantly correlated to the onset of AGI. In the multivariate analysis, prolonged hospital stays odds ratio (OR 1.05; P = 0.03), malignancy (OR 5.82; P = 0.03) and alcohol abuse (OR 42.41; P = 0.002) maintained a significant association. CONCLUSIONS: The risk of AGI seems to be higher in patients with concurrent malignancy, alcohol abuse or prolonged hospital stays. Strategies to mitigate this complication in these patients are of utmost importance.


Assuntos
Alcoolismo , Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Infecções Relacionadas à Prótese , Humanos , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Estudos Retrospectivos , Estudos de Casos e Controles , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/cirurgia , Infecções Relacionadas à Prótese/microbiologia , Alcoolismo/etiologia , Alcoolismo/cirurgia , Resultado do Tratamento , Fatores de Risco , Aneurisma da Aorta Abdominal/cirurgia
9.
Lasers Med Sci ; 38(1): 2, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36534293

RESUMO

Gels with high concentrations of hydrogen peroxide (H2O2) have been associated with cytotoxicity and consequent post-bleaching tooth sensitivity. This study assessed the bleaching efficacy (BE) and cytotoxicity (CT) of bleaching gels with low concentrations of H2O2 containing manganese oxide (MnO2) and photocatalyzed with violet LED (LEDv). The following groups were established: G1: no treatment (negative control, NC); G2: 35% H2O2 (positive control, PC); G3: LEDv; G4: 10% H2O2; G5: 6% H2O2; G6: 10% H2O2 + MnO2 + LEDv; G7: 6% H2O2 + MnO2 + LEDv. To analyze BE, standardized enamel/dentin discs (E/DDs) were subjected to the bleaching procedures for 45 min (1 session). The color change was determined before and after performing the bleaching protocols (ΔE00; ΔWI). To analyze CT, the E/DDs were adapted to artificial pulp chambers, and the extracts (culture medium + diffused gel components) were applied to cultured odontoblast-like MDPC-23 cells. Then, the cells were assessed concerning their viability (VB), oxidative stress (OxS), and Live/Dead. The amount of H2O2 diffused was also determined (ANOVA/Tukey; p < 0.05). Cell viability decreased in all bleached groups compared to G1 (NC; p < 0.05). The cells in G6 and G7 presented higher viability than in G2, G4, and G5 (p < 0.05). The BE in G7 was similar to G2 (PC; p < 0.05). The lowest OxS and H2O2 diffusion values were found in G6 and G7, compared to the other bleached groups (G2, G4, and G5; p < 0.05). The 6% H2O2 bleaching gel (G7) submitted to both methods of catalysis (MnO2 + LEDv) caused only a mild cytotoxicity and maintained the excellent esthetic outcome promoted by in-office conventional tooth bleaching.


Assuntos
Clareadores Dentários , Clareamento Dental , Peróxido de Hidrogênio , Compostos de Manganês , Óxidos , Clareamento Dental/métodos , Géis
10.
Women Health ; 62(1): 68-74, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34965850

RESUMO

Hyperuricemia (HU) has been associated with cardiovascular risk and metabolic syndrome (MS) worldwide. However, inconsistencies about this relation are still reported, and it is not clear whether hyperuricemia is an independent risk factor for MS. The aim of this study was to determine hyperuricemia associations with systemic hypertension and MS in women from northeast Brazil. The study included 301 women. Hyperuricemia was considered for serum uric acid (SUA) ≥6 mg/dL. Insulin resistance (IR) was measured by TyG index (TyG ≥ 4.55). Fisher test and Multivariate logistic regression analyses estimated the association between hyperuricemia (or SUA level) and systemic hypertension and MS. Hyperuricemia association with systemic hypertension was independent of age, body-mass index (BMI), smoking and alcoholism (OR: OR: 4.6050; p = .000256), and MS components (OR: 4.1296; IC95% 1.8330_9.3033; p = .000621). Hyperuricemia increased risk of systemic hypertension by 4,6 -fold. SUA level was associated with MS, independently of other classic component factors of the syndrome (OR:1.34, p = .0129). Hyperuricemia and high SUA levels were associated with MS and systemic hypertension. Effect of hyperuricemia in systemic hypertension is independent of age, BMI, lifestyle, and MS factors. SUA levels are independently associated with MS.


Assuntos
Hipertensão , Síndrome Metabólica , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Síndrome Metabólica/epidemiologia , Fatores de Risco , Ácido Úrico
11.
J Vasc Surg ; 74(1): 276-284.e4, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33348004

RESUMO

BACKGROUND: Vascular graft infections are a serious complication in vascular surgery. Correct antibiotic therapy targeted to the most likely infecting species is essential to treat these patients, although the bacterial epidemiology and pathogenesis are still not completely understood. We analyzed the behavior of vascular graft infections and the microbiologic patterns of resistance. METHODS: A 10-year (2008-2018), single-center, retrospective cohort study was performed of all patients admitted with vascular graft infection identified by positive direct graft cultures. An extensive microbiologic study was performed to analyze the bacterial strains, antibiotic resistance and sensitivity, and prevalence stratified by the year. RESULTS: A total of 72 vascular graft infections with positive graft cultures occurring in 65 patients were found. Their mean age was 67 ± 9.6 years, and 85% were men. Infection-related mortality was 11%. Of the 65 patients, 14 had undergone aortobifemoral bypass, 13 axillofemoral bypass, 5 femorofemoral bypass, 27 femoropopliteal bypass, and 4 femoral endarterectomy with synthetic patch angioplasty. The median interval from the index procedure to infection was longer for intracavitary than for extracavitary grafts (P = .011). Of the 72 infections, 48 were monomicrobial and 24 were polymicrobial. Gram-negative bacteria were predominantly identified in intracavitary graft infections (54%). In contrast, gram-positive bacteria were most frequent in the extracavitary graft group (58%). Multidrug-resistant bacterial species occurred more frequently in early graft infections (P = .002). Throughout the study duration, an overall decrease in gram-positive infections and an increase in gram-negative infections was observed, especially in extensively drug-resistant strains. A similar progression was found in all nosocomial infections. CONCLUSIONS: The present study has shown that vascular graft infection microbiology changed in accordance with graft location and interval to infection from revascularization surgery and had also evolved over the study period with patterns similar to those for all nosocomial infections. This highlights the importance of studying the specific microbiology of each healthcare center and its relationship to vascular graft infections to achieve the best treatment possible.


Assuntos
Bactérias/isolamento & purificação , Implante de Prótese Vascular/efeitos adversos , Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/microbiologia , Idoso , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Implante de Prótese Vascular/instrumentação , Remoção de Dispositivo , Farmacorresistência Bacteriana , Feminino , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/terapia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento
12.
Eur J Nutr ; 60(6): 3303-3313, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33598774

RESUMO

PURPOSE: The WHO has proposed a novel model of healthy aging called intrinsic capacity (IC). However, the association between dietary patterns and IC is unclear. We aimed to investigate the prospective associations between dietary patterns and IC trajectories over a 3-year period in community-dwelling Japanese adults aged ≥ 60 years. METHODS: A prospective cohort study which contained nutritional status, mental status, and physical function was used. A validated 34-item food frequency questionnaire was used to determine dietary intake and to derive five dietary patterns ("fruits and vegetables", "sugar and fat", "salt and pickles", "noodle and alcohol", and "protein-rich") using principal component analysis. The composite IC score was calculated as the mean of the locomotion Z-score, cognition Z-score, psychological Z-score, vitality Z-score, and sensory regression score. A generalized estimating equation was applied for longitudinal analysis. RESULTS: A total of 666 enrollees were included in the analysis. The mean baseline IC was 0.07 ± 0.47. The "fruits and vegetables" dietary pattern was positively associated with composite IC score changes after adjusting for confounders (Q4 vs. Q1: mean difference [0.069], P = 0.019). Similarly, a positive correlation was observed for the "protein-rich" dietary pattern with the composite IC score changes (Q4 vs. Q1: mean difference [0.092], Q3 vs. Q1: mean difference [0.101], Q2 vs. Q1: mean difference [0.083]; all P < 0.01). However, adherence to the "sugar and fat" dietary pattern was negatively associated with composite IC score changes (Q4 vs. Q1: mean difference [- 0.072], P = 0.026). Furthermore, the percentage of animal protein to total protein intake showed a significant incremental trend in the "protein-rich" dietary pattern (P for trend < 0.001). CONCLUSION: The "fruits and vegetables" and "protein-rich" (animal-based protein in particular) dietary patterns were positively associated with IC changes, whereas the "sugar and fat" dietary pattern was negatively associated with IC changes. Identification and promotion of healthy dietary patterns in older adults may inform future health policies and research.


Assuntos
Dieta , Vida Independente , Idoso , Animais , Frutas , Humanos , Estudos Prospectivos , Verduras
13.
BMC Geriatr ; 21(1): 515, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579661

RESUMO

BACKGROUND: Social frailty is associated with poor health outcomes; however, its effects on healthy aging indicators have not been adequately investigated. This study assessed the longitudinal association between social frailty and the intrinsic capacity of community-dwelling older adults. METHODS: A total of 663 participants (56.7% women) aged ≥60 years from in Nagoya, Japan, were included in the study. The first measurement occurred in 2014, and annual follow-ups occurred until 2017. Social frailty was determined based on four items: financial difficulty, household status, social activity, and regular contact with others. A deficit score of 0 represented social robustness, 1 represented social prefrailty, and ≥ 2 represented social frailty. Intrinsic capacity was evaluated by the locomotion, cognition, psychological function, vitality, and sensory function domains. The longitudinal association was analyzed using generalized estimating equations. RESULTS: The prevalence of social prefrailty and social frailty at baseline was 31.2 and 6.3%, respectively. The social prefrailty group (ß = - 0.132, P < 0.001) and social frailty group (ß = - 0.258, P < 0.001) were associated with a greater reduction in the composite intrinsic capacity scores than the social robustness group, especially in the cognition, psychological function, and vitality domains. Men with social prefrailty/social frailty demonstrated a greater decrease in the psychological function domain score (- 0.512 vs. - 0.278) than women. Additionally, the cognition domain score only decreased in men in the social prefrailty/social frailty group (ß = - 0.122, P = 0.016). CONCLUSIONS: Social frailty was associated with intrinsic capacity and its subdomains longitudinally. Men with social frailty were more vulnerable than women to a decline in their psychological function and cognition domains. Therefore, the advanced management of social frailty is necessary to facilitate healthy aging.


Assuntos
Fragilidade , Idoso , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Humanos , Vida Independente , Japão/epidemiologia , Masculino , Prevalência , Estudos Prospectivos
14.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803585

RESUMO

Methylmercury (MeHg) toxicity is a major environmental concern. In the aquatic reservoir, MeHg bioaccumulates along the food chain until it is consumed by riverine populations. There has been much interest in the neurotoxicity of MeHg due to recent environmental disasters. Studies have also addressed the implications of long-term MeHg exposure for humans. The central nervous system is particularly susceptible to the deleterious effects of MeHg, as evidenced by clinical symptoms and histopathological changes in poisoned humans. In vitro and in vivo studies have been crucial in deciphering the molecular mechanisms underlying MeHg-induced neurotoxicity. A collection of cellular and molecular alterations including cytokine release, oxidative stress, mitochondrial dysfunction, Ca2+ and glutamate dyshomeostasis, and cell death mechanisms are important consequences of brain cells exposure to MeHg. The purpose of this review is to organize an overview of the mercury cycle and MeHg poisoning events and to summarize data from cellular, animal, and human studies focusing on MeHg effects in neurons and glial cells. This review proposes an up-to-date compendium that will serve as a starting point for further studies and a consultation reference of published studies.


Assuntos
Encéfalo/patologia , Inflamação/patologia , Compostos de Metilmercúrio/toxicidade , Síndromes Neurotóxicas/patologia , Animais , Bioacumulação , Encéfalo/efeitos dos fármacos , Humanos , Compostos de Metilmercúrio/farmacocinética , Microbiota/efeitos dos fármacos , Síndromes Neurotóxicas/microbiologia , Síndromes Neurotóxicas/prevenção & controle , Síndromes Neurotóxicas/terapia
15.
Bull Environ Contam Toxicol ; 107(5): 801-808, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34081149

RESUMO

Methylmercury (MeHg) is a toxic and bioaccumulative organo-metallic compound that is naturally produced in many ecosystems. Organisms that occupy the lower trophic positions in food webs may be key factors in the assessment of MeHg biomagnification between ecosystems. Here we present a review of the peer-reviewed literature examining MeHg bioaccumulation in freshwater invertebrates, focused principally on insects. This review aims to characterize the invertebrates that bioaccumulate higher MeHg concentrations and therefore pose a higher risk to upper trophic levels and to clarify which ecosystems are more susceptible to bioaccumulation in lower trophic levels. However, we found that few studies provided robust environmental data (notably water chemistry) as part of their papers, dramatically limiting our ability to test for factors that might contribute to different concentrations of MeHg in invertebrates. We highlight the importance of providing physical and chemical characteristics of study sites in publications examining MeHg bioaccumulation and biomagnification. Adopting the proposed recommendations will improve the available information for future mercury risk assessment analyses.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Cadeia Alimentar , Água Doce , Invertebrados , Mercúrio/análise , Poluentes Químicos da Água/análise
16.
Pflugers Arch ; 472(3): 325-334, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31925527

RESUMO

The ablation of renal nerves, by destroying both the sympathetic and afferent fibers, has been shown to be effective in lowering blood pressure in resistant hypertensive patients. However, experimental studies have reported that the removal of sympathetic fibers may lead to side effects, such as the impairment of compensatory cardiorenal responses during a hemodynamic challenge. In the present study, we evaluated the effects of the selective removal of renal afferent fibers on arterial hypertension, renal sympathetic nerve activity, and renal changes in a model of renovascular hypertension. After 4 weeks of clipping the left renal artery, afferent renal denervation (ARD) was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of ARD, we found reduced MAP (~ 18%) and sympathoexcitation to both the ischemic and contralateral kidneys in the hypertensive group. Moreover, a reduction in reactive oxygen species was observed in the ischemic (76%) and contralateral (27%) kidneys in the 2K1C group. In addition, ARD normalized renal function markers and proteinuria and podocin in the contralateral kidney. Taken altogether, we show that the selective removal of afferent fibers is an effective method to reduce MAP and improve renal changes without compromising the function of renal sympathetic fibers in the 2K1C model. Renal afferent nerves may be a new target in neurogenic hypertension and renal dysfunction.


Assuntos
Vias Aferentes/fisiopatologia , Hipertensão Renovascular/fisiopatologia , Isquemia/fisiopatologia , Nefropatias/fisiopatologia , Rim/fisiopatologia , Animais , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Masculino , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Ratos , Ratos Wistar , Sistema Nervoso Simpático/fisiopatologia
17.
Pharmacol Res ; 161: 105198, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32942016

RESUMO

Methylglyoxal was shown to impair adipose tissue capillarization and insulin sensitivity in obese models. We hypothesized that glyoxalase-1 (GLO-1) activity could be diminished in the adipose tissue of type 2 diabetic obese patients. Moreover, we assessed whether such activity could be increased by GLP-1-based therapies in order to improve adipose tissue capillarization and insulin sensitivity. GLO-1 activity was assessed in visceral adipose tissue of a cohort of obese patients. The role of GLP-1 in modulating GLO-1 was assessed in type 2 diabetic GK rats submitted to sleeve gastrectomy or Liraglutide treatment, in the adipose tissue angiogenesis assay and in the HUVEC cell line. Glyoxalase-1 activity was decreased in visceral adipose tissue of pre-diabetic and diabetic obese patients, together with other markers of adipose tissue dysfunction and correlated with increased HbA1c levels. Decreased adipose tissue GLO-1 levels in GK rats were increased by sleeve gastrectomy and Liraglutide, being associated with overexpression of angiogenic and vasoactive factors, as well as insulin receptor phosphorylation (Tyr1161). Moreover, GLP-1 increased adipose tissue capillarization and HUVEC proliferation in a glyoxalase-dependent manner. Lower adipose tissue GLO-1 activity was observed in dysmetabolic patients, being a target for GLP-1 in improving adipose tissue capillarization and insulin sensitivity.


Assuntos
Tecido Adiposo/irrigação sanguínea , Capilares/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Incretinas/farmacologia , Resistência à Insulina , Lactoilglutationa Liase/metabolismo , Liraglutida/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Adulto , Idoso , Animais , Capilares/enzimologia , Capilares/fisiopatologia , Células Cultivadas , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Feminino , Gastrectomia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/enzimologia , Obesidade/fisiopatologia , Obesidade/cirurgia , Ratos Wistar , Transdução de Sinais
18.
Anim Cogn ; 23(4): 629-642, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32152923

RESUMO

Oceans are extremely dynamic environments, which poses challenges for top-predators such as seabirds to find food resources. Yet, seabirds evolved sensorial abilities (olfactory senses) along with complex behaviours (social information transfer through local enhancement) to improve foraging efficiency. Using the Cory's shearwater (Calonectris borealis) as a model species, we developed an individual-based model to explore the complementary role of different searching mechanisms (olfactory foraging and local enhancement) for the optimal foraging behaviour of pelagic seabirds during 1-day foraging trips around breeding colonies. Model outputs were compared with observed patterns of Cory's shearwaters distribution during local foraging trips. Also, the foraging efficiency of virtual individuals was analysed considering hypothetical scenarios of foraging conditions and densities of foraging individuals around breeding colonies. The results support the use of a combination of searching strategies by Cory's shearwaters, which produced representative patterns of space use from tracked individuals, including spatial foraging segregation of neighbouring sub-colonies. Furthermore, while the mechanisms underpinning local enhancement played a key role in mitigating sub-optimal foraging conditions, the use of olfactory senses conferred great adaptive foraging advantages over a wide range of environmental conditions. Our results also indicate a synergistic effect between the two strategies, which suggests that a multimodal foraging strategy is useful to forage in extremely dynamic environments. The developed model provides a basis for further investigation regarding the role of foraging mechanisms in the population dynamics of colonial animals, including the adaptive foraging behaviour of marine top predators to dynamic environmental conditions.


Assuntos
Sinais (Psicologia) , Olfato , Animais , Aves , Comportamento Alimentar , Oceanos e Mares
19.
Support Care Cancer ; 28(7): 3451-3457, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31802252

RESUMO

PURPOSE: The objectives of this study were to describe the distribution and the clinicopathological features of the most common causes for dental treatment needs during the hospitalization of cancer patients. METHODS: A retrospective cohort study of 2664 hospitalized cancer patients that analyzed the main dental treatment needs and dental procedures performed from January 2010 to December 2017. RESULTS: A total of 2664 medical patients were included in this study. Non-Hodgkin lymphoma (17.2%) was the most common cancer type, followed by leukemia (14.8%), and oral and oropharyngeal squamous cell carcinoma (10.5%). The most common reasons for patients' hospitalization were chemotherapy protocols (18.8%), monitoring head and neck surgeries (9.7%), and febrile neutropenia (9.6%). The main motivation for the medical team to request dental evaluation was oral mucositis (22.8%) followed by oral pain or toothache (10.8%) and fungal, viral oral infections or traumatic oral lesions (9.9%). The dental treatment needs most observed were pain due to oral mucositis (17%), dental treatment prior to radiotherapy (RT), chemotherapy (CT) or bisphosphonate therapy (BP) (10.8%), teeth extractions (6.5%), and prophylactic photobiomodulation therapy (6.3%), whereas the most common dental treatments performed were oral hygiene protocols (30.2%), photobiomodulation therapy (prophylactic and curative) (21.7%), and dental treatment prior to cancer treatment initiation (RT, CT, and BP) (9.5%). CONCLUSION: This study can be considered original in the oncologic context, providing new information about the most frequent dental treatment needs among a large population of hospitalized cancer patients.


Assuntos
Assistência Odontológica/métodos , Neoplasias/enfermagem , Neoplasias/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Institutos de Câncer , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
20.
Mar Drugs ; 19(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374188

RESUMO

Over the last decades, antifouling coatings containing biocidal compounds as active ingredients were used to prevent biofouling, and eco-friendly alternatives are needed. Previous research from our group showed that polymethoxylated chalcones and glycosylated flavones obtained by synthesis displayed antifouling activity with low toxicity. In this work, ten new polymethoxylated flavones and chalcones were synthesized for the first time, including eight with a triazole moiety. Eight known flavones and chalcones were also synthesized and tested in order to construct a quantitative structure-activity relationship (QSAR) model for these compounds. Three different antifouling profiles were found: three compounds (1b, 11a and 11b) exhibited anti-settlement activity against a macrofouling species (Mytilus galloprovincialis), two compounds (6a and 6b) exhibited inhibitory activity against the biofilm-forming marine bacteria Roseobacter litoralis and one compound (7b) exhibited activity against both mussel larvae and microalgae Navicula sp. Hydrogen bonding acceptor ability of the molecule was the most significant descriptor contributing positively to the mussel larvae anti-settlement activity and, in fact, the triazolyl glycosylated chalcone 7b was the most potent compound against this species. The most promising compounds were not toxic to Artemia salina, highlighting the importance of pursuing the development of new synthetic antifouling agents as an ecofriendly and sustainable alternative for the marine industry.


Assuntos
Incrustação Biológica/prevenção & controle , Flavonoides/farmacologia , Glicosídeos/farmacologia , Microalgas/efeitos dos fármacos , Mytilus/efeitos dos fármacos , Roseobacter/efeitos dos fármacos , Triazóis/farmacologia , Animais , Artemia/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Química Click , Flavonoides/síntese química , Flavonoides/toxicidade , Glicosídeos/síntese química , Glicosídeos/toxicidade , Química Verde , Ligação de Hidrogênio , Microalgas/crescimento & desenvolvimento , Estrutura Molecular , Mytilus/crescimento & desenvolvimento , Relação Quantitativa Estrutura-Atividade , Roseobacter/crescimento & desenvolvimento , Triazóis/síntese química , Triazóis/toxicidade , Microbiologia da Água
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