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3.
Pathogens ; 13(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38392866

RESUMO

Antifungal therapy, especially with the azoles, could promote the incidence of less susceptible isolates of Cryptococcus neoformans and C. gattii species complexes (SC), mostly in developing countries. Given that these species affect mostly the immunocompromised host, the infections are severe and difficult to treat. This review encompasses the following topics: 1. infecting species and their virulence, 2. treatment, 3. antifungal susceptibility methods and available categorical endpoints, 4. genetic mechanisms of resistance, 5. clinical resistance, 6. fluconazole minimal inhibitory concentrations (MICs), clinical outcome, 7. environmental influences, and 8. the relevance of host factors, including pharmacokinetic/pharmacodynamic (PK/PD) parameters, in predicting the clinical outcome to therapy. As of now, epidemiologic cutoff endpoints (ECVs/ECOFFs) are the most reliable antifungal resistance detectors for these species, as only one clinical breakpoint (amphotericin B and C. neoformans VNI) is available.

4.
Diabetol Metab Syndr ; 16(1): 23, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238868

RESUMO

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common liver disease affecting 30% of the world's population and is often associated with metabolic disorders such as metabolic syndrome, type 2 diabetes (T2D), and cardiovascular disease. This review is an update of the Brazilian Diabetes Society (Sociedade Brasileira de Diabetes [SBD]) evidence-based guideline for the management of MASLD in clinical practice. METHODS: The methodology was published previously and was defined by the internal institutional steering committee. The SBD Metabolic Syndrome and Prediabetes Department drafted the manuscript, selecting key clinical questions for a narrative review using MEDLINE via PubMed with the MeSH terms [diabetes] and [fatty liver]. The best available evidence was reviewed, including randomized clinical trials (RCTs), meta-analyses, and high-quality observational studies related to MASLD. RESULTS AND CONCLUSIONS: The SBD Metabolic Syndrome and Prediabetes Department formulated 9 recommendations for the management of MASLD in people with prediabetes or T2D. Screening for the risk of advanced fibrosis associated with MASLD is recommended in all adults with prediabetes or T2D. Lifestyle modification (LSM) focusing on a reduction in body weight of at least 5% is recommended as the first choice for these patients. In situations where LSMs are insufficient to achieve weight loss, the use of anti-obesity medications is recommended for those with a body mass index (BMI) ≥ 27 kg/m2. Pioglitazone and glucagon-like peptide-1 receptor agonists (GLP-1RA) monotherapy are the first-line pharmacological treatments for steatohepatitis in people with T2D, and sodium-glucose cotransporter-2 (SGLT2) inhibitors may be considered in this context. The combination of these agents may be considered in the treatment of steatohepatitis and/or fibrosis, and bariatric surgery should be considered in patients with a BMI ≥ 35 kg/m2, in which the combination of LSM and pharmacotherapy has not been shown to be effective in improving MASLD.

5.
Brain Topogr ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38060074

RESUMO

PURPOSE: Identify the presence of a dysfunctional electroencephalographic (EEG) pattern in individuals with sickle cell disease (SCD) and hip osteonecrosis, and assess its potential associations with depression, anxiety, pain severity, and serum levels of brain-derived neurotrophic factor (BDNF). METHODS: In this cross-sectional investigation, 24 SCD patients with hip osteonecrosis and chronic pain were matched by age and sex with 19 healthy controls. Resting-state EEG data were recorded using 32 electrodes for both groups. Power spectral density (PSD) and peak alpha frequency (PAF) were computed for each electrode across Delta, Theta, Alpha, and Beta frequency bands. Current Source Density (CSD) measures were performed utilizing the built-in Statistical nonparametric Mapping Method of the LORETA-KEY software. RESULTS: Our findings demonstrated that SCD individuals exhibited higher PSD in delta and theta frequency bands when compared to healthy controls. Moreover, SCD individuals displayed increased CSD in delta and theta frequencies, coupled with decreased CSD in the alpha frequency within brain regions linked to pain processing, motor function, emotion, and attention. In comparison to the control group, depression symptoms, and pain intensity during hip abduction were positively correlated with PSD and CSD in the delta frequency within the parietal region. Depression symptoms also exhibited a positive association with PSD and CSD in the theta frequency within the same region, while serum BDNF levels showed a negative correlation with CSD in the alpha frequency within the left insula. CONCLUSION: This study indicates that individuals with SCD experiencing hip osteonecrosis and chronic pain manifest a dysfunctional EEG pattern characterized by the persistence of low-frequency PSD during a resting state. This dysfunctional EEG pattern may be linked to clinical and biochemical outcomes, including depression symptoms, pain severity during movement, and serum BDNF levels.

6.
Insects ; 14(8)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37623407

RESUMO

Drosophila suzukii, an invasive insect pest, poses a significant threat to various fruit crops. The use of broad-spectrum insecticides to control this pest can reduce the effectiveness of biological control agents, such as the parasitoid Trichopria anastrephae. Here, we evaluated the toxicity of newly synthesized lactone derivatives on D. suzukii and their selectivity towards T. anastrephae. We used in silico approaches to identify potential targets from the most promising molecules in the D. suzukii nervous system and to understand potential differences in susceptibilities between D. suzukii and its parasitoid. Of the nine molecules tested, (rac)-8 and compound 4 demonstrated efficacy against the fly. Exposure to the estimated LC90 of (rac)-8 and compound 4 resulted in a mortality rate of less than 20% for T. anastrephae without impairing the parasitoid's functional parasitism. The in silico predictions suggest that (rac)-8 and compound 4 target gamma amino butyric acid (GABA) receptors and transient receptor potential (TRP) channels of D. suzukii. However, only the reduced interaction with TRP channels in T. anastrephae demonstrated a potential reason for the selectivity of these compounds on the parasitoid. Our findings suggest the potential for integrating (rac)-8 and compound 4 into D. suzukii management practices.

7.
Diabetol Metab Syndr ; 15(1): 160, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468901

RESUMO

BACKGROUND: The management of antidiabetic therapy in people with type 2 diabetes (T2D) has evolved beyond glycemic control. In this context, Brazil and Portugal defined a joint panel of four leading diabetes societies to update the guideline published in 2020. METHODS: The panelists searched MEDLINE (via PubMed) for the best evidence from clinical studies on treating T2D and its cardiorenal complications. The panel searched for evidence on antidiabetic therapy in people with T2D without cardiorenal disease and in patients with T2D and atherosclerotic cardiovascular disease (ASCVD), heart failure (HF), or diabetic kidney disease (DKD). The degree of recommendation and the level of evidence were determined using predefined criteria. RESULTS AND CONCLUSIONS: All people with T2D need to have their cardiovascular (CV) risk status stratified and HbA1c, BMI, and eGFR assessed before defining therapy. An HbA1c target of less than 7% is adequate for most adults, and a more flexible target (up to 8%) should be considered in frail older people. Non-pharmacological approaches are recommended during all phases of treatment. In treatment naïve T2D individuals without cardiorenal complications, metformin is the agent of choice when HbA1c is 7.5% or below. When HbA1c is above 7.5% to 9%, starting with dual therapy is recommended, and triple therapy may be considered. When HbA1c is above 9%, starting with dual therapyt is recommended, and triple therapy should be considered. Antidiabetic drugs with proven CV benefit (AD1) are recommended to reduce CV events if the patient is at high or very high CV risk, and antidiabetic agents with proven efficacy in weight reduction should be considered when obesity is present. If HbA1c remains above target, intensification is recommended with triple, quadruple therapy, or even insulin-based therapy. In people with T2D and established ASCVD, AD1 agents (SGLT2 inhibitors or GLP-1 RA with proven CV benefit) are initially recommended to reduce CV outcomes, and metformin or a second AD1 may be necessary to improve glycemic control if HbA1c is above the target. In T2D with HF, SGLT2 inhibitors are recommended to reduce HF hospitalizations and mortality and to improve HbA1c. In patients with DKD, SGLT2 inhibitors in combination with metformin are recommended when eGFR is above 30 mL/min/1.73 m2. SGLT2 inhibitors can be continued until end-stage kidney disease.

8.
Diabetol Metab Syndr ; 15(1): 2, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36593495

RESUMO

INTRODUCTION: For individuals diagnosed with diabetes mellitus, the practice of properly oriented physical exercises brings significant benefits to the individual's health and is considered an indispensable tool for metabolic management. The individualization of exercise routines is an essential aspect for therapeutic success, despite the need to consider some general recommendations. This review is an authorized literal translation of the Brazilian Society of Diabetes (SBD) Guidelines 2021-2022, which is based on scientific evidence and provides guidance on physical activities and exercises aimed at individuals with type 1 and 2 diabetes. METHODS: SBD designated 9 specialists from its "Department of Diabetes, Exercise & Sports" to author chapters on physical activities and exercises directed to individuals with type 1 and 2 diabetes. The aim of these chapters was to highlight recommendations in accordance with Evidence Levels, based on what is described in the literature. These chapters were analyzed by the SBD Central Committee, which is also responsible for the SBD 2021-2022 guidelines. Main clinical inquiries were selected to perform a narrated review by using MEDLINE via PubMed. Top available evidence, such as high-quality clinical trials, large observational studies and meta-analyses related to physical activity and exercise advisory, were analyzed. The adopted MeSh terms were [diabetes], [type 1 diabetes], [type 2 diabetes], [physical activity] [physical exercise]. RESULTS: 17 recommendations were defined by the members. For this review, it was considered different Evidence Levels, as well as different Classes of Recommendations. As to Evidence Levels, the following levels were contemplated: Level A) More than one randomized clinical trial or a randomized clinical trial meta-analysis with low heterogeneity. Level B) Meta analysis with observational studies, one randomized clinical trial, sizeable observational studies and sub-groups analysis. Level C) Small non-randomized studies, cross-sectional studies, case control studies, guidelines or experts' opinions. In respect to Recommendation Classes, the following criteria were adopted: I. "Recommended": Meaning there was a consent of more than 90% of the panel; IIa. "Must be considered": meaning there is a general preference of the panel which 70-90% agrees; IIb. "Can be considered". 50-70% agrees; III Not recommended: There is a consensus that the intervention should not be performed. CONCLUSION: Physical exercise aids on the glycemic control of type 2 diabetes individuals while also decreasing cardiovascular risk in individuals with type 1 and 2 diabetes. Individuals diagnosed with diabetes should perform combined aerobic and resistance exercises in order to manage the disease. In addition, exercises focusing on flexibility and balance should be specially addressed on elderly individuals. Diabetes individuals using insulin as therapeutic treatment should properly monitor glycemia levels before, during and after exercise sessions to minimize health incidents, such as hypoglycemia.

9.
Diabetol Metab Syndr ; 14(1): 189, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36510287

RESUMO

BACKGROUND: Insulin therapy regimens for people with type 1 diabetes (PWT1D) should mimic the physiological insulin secretion that occurs in individuals without diabetes. Intensive insulin therapy, whether by multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII), constitutes the fundamental therapy from the initial stages of type 1 diabetes (T1D), at all ages. This review is an authorized literal translation of part of the Brazilian Diabetes Society (SBD) Guidelines 2021-2022. This evidence-based guideline supplies guidance on insulin therapy in T1D. METHODS: The methods were published elsewhere in earlier SBD guidelines and was approved by the Internal Institutional Steering Committee for publication. Briefly, the Brazilian Diabetes Society indicated fourteen experts to constitute the Central Committee, designed to regulate the method review of the manuscripts, and judge the degrees of recommendations and levels of evidence. SBD Type 1 Diabetes Department drafted the manuscript selecting key clinical questions to do a narrative review using MEDLINE via PubMed, with the best evidence available, including high-quality clinical trials, metanalysis, and large observational studies related to insulin therapy in T1D, by using the Mesh terms [type 1 diabetes] and [insulin]. RESULTS: Based on extensive literature review the Central Committee defined ten recommendations. Three levels of evidence were considered: A. Data from more than one randomised clinical trial (RCT) or one metanalysis of RCTs with low heterogeneity (I2 < 40%). B. Data from metanalysis, including large observational studies, a single RCT, or a pre-specified subgroup analysis. C: Data from small or non-randomised studies, exploratory analysis, or consensus of expert opinion. The degree of recommendation was obtained based on a poll sent to the panellists, using the following criteria: Grade I: when more than 90% of agreement; Grade IIa if 75-89% of agreement; IIb if 50-74% of agreement, and III, when most of the panellist recommends against a defined treatment. CONCLUSIONS: In PWT1D, it is recommended to start insulin treatment immediately after clinical diagnosis, to prevent metabolic decompensation and diabetic ketoacidosis. Insulin therapy regimens should mimic insulin secretion with the aim to achieve glycemic control goals established for the age group. Intensive treatment with basal-bolus insulin therapy through MDI or CSII is recommended, and insulin analogues offers some advantages in PWT1D, when compared to human insulin. Periodic reassessment of insulin doses should be performed to avoid clinical inertia in treatment.

10.
Plants (Basel) ; 11(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501335

RESUMO

The use of formulations containing botanical products for controlling insects that vector human and animal diseases has increased in recent years. Plant extracts seem to offer fewer risks to the environment and to human health without reducing the application strategy's efficacy when compared to synthetic and conventional insecticides and repellents. Here, we evaluated the potential of extracts obtained from caninana, Chiococca alba (L.) Hitchc. (Rubiaceae), plants as a tool to be integrated into the management of Aedes aegypti, one of the principal vectors for the transmission of arborviruses in humans. We assessed the larvicidal and repellence performance against adult mosquitoes and evaluated the potential undesired effects of the extracts on non-target organisms. We assessed the susceptibility and predatory abilities of the nymphs of Belostoma anurum, a naturally occurring mosquito larva predator, and evaluated the C. alba extract's cytotoxic effects in mammalian cell lines. Our chromatographic analysis revealed 18 compounds, including rutin, naringin, myricetin, morin, and quercetin. The methanolic extracts of C. alba showed larvicidal (LC50 = 82 (72-94) mg/mL) activity without killing or affecting the abilities of B. anurum to prey upon mosquito larvae. Our in silico predictions revealed the molecular interactions between rutin and the AeagOBP1 receptor to be one possible mechanism for the repellent potential recorded for formulations containing C. alba extracts. Low cytotoxicity against mammalian cell lines reinforces the selectivity of C. alba extracts. Collectively, our findings highlight the potential of C. alba and one of its constituents (rutin) as alternative tools to be integrated into the management of A. aegypti mosquitoes.

11.
Molecules ; 27(16)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36014413

RESUMO

The use of plant-based products has been shown to efficiently inhibit fungi-mediated diseases in agricultural crops. Here, we extracted and evaluated the composition of noni, Morinda citrifolia L., essential oil and assessed its activities against Stagonosporopsis cucurbitacearum in Cucumis melo L. Using in silico molecular approaches, potential interactions between the essential oil major components and S. cucurbitacearum tyrosine-tRNA ligase were predicted. Finally, we also measured the potential interference of plant physiology (the stomatal conductance and net photosynthesis) mediated by the application of the M. citrifolia essential oil. Chromatographic analysis revealed that octanoic acid (75.8%), hexanoic acid (12.8%), and isobutyl pent-4-enyl carbonate (3.1%) were the major essential oil compounds. Octanoic acid and noni essential oil, when used as preventive measures, reduce fungal mycelial growth at a concentration of 5 mg/mL without causing significant damage to the treated leaves, which reinforces their efficacies as preventive tools against S. cucurbitacearum. Molecular docking analyses predicted very stable interactions between the major essential oil constituents and S. cucurbitacearum tyrosine-tRNA ligase, suggesting the interference of these plant-based molecules upon enzyme activation. Octanoic acid and M. citrifolia essential oil at concentrations of 20 mg/mL decreased the stomatal conductance and net photosynthesis rate of melon plants, resulting in robust phytotoxicity. Collectively, our findings indicated that despite the phytotoxicity risks at higher concentrations, M. citrifolia essential oil and octanoic acid, have potential as alternative tools for the integrative management of S. cucurbitacearum.


Assuntos
Morinda , Óleos Voláteis , Tirosina-tRNA Ligase , Ascomicetos , Caprilatos , Simulação de Acoplamento Molecular , Morinda/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química
12.
PLoS One ; 17(3): e0264643, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35231063

RESUMO

Dengue virus (DENV) causes a major arthropod-borne viral disease, with 2.5 billion people living in risk areas. DENV consists in a 50 nm-diameter enveloped particle in which the surface proteins are arranged with icosahedral symmetry, while information about nucleocapsid (NC) structural organization is lacking. DENV NC is composed of the viral genome, a positive-sense single-stranded RNA, packaged by the capsid (C) protein. Here, we established the conditions for a reproducible in vitro assembly of DENV nucleocapsid-like particles (NCLPs) using recombinant DENVC. We analyzed NCLP formation in the absence or presence of oligonucleotides in solution using small angle X-ray scattering, Rayleigh light scattering as well as fluorescence anisotropy, and characterized particle structural properties using atomic force and transmission electron microscopy imaging. The experiments in solution comparing 2-, 5- and 25-mer oligonucleotides established that 2-mer is too small and 5-mer is sufficient for the formation of NCLPs. The assembly process was concentration-dependent and showed a saturation profile, with a stoichiometry of 1:1 (DENVC:oligonucleotide) molar ratio, suggesting an equilibrium involving DENVC dimer and an organized structure compatible with NCLPs. Imaging methods proved that the decrease in concentration to sub-nanomolar concentrations of DENVC allows the formation of regular spherical NCLPs after protein deposition on mica or carbon surfaces, in the presence as well as in the absence of oligonucleotides, in this latter case being surface driven. Altogether, the results suggest that in vitro assembly of DENV NCLPs depends on DENVC charge neutralization, which must be a very coordinated process to avoid unspecific aggregation. Our hypothesis is that a specific highly positive spot in DENVC α4-α4' is the main DENVC-RNA binding site, which is required to be firstly neutralized to allow NC formation.


Assuntos
Vírus da Dengue , Proteínas do Capsídeo/genética , Vírus da Dengue/genética , Humanos , Nucleocapsídeo/metabolismo , Oligonucleotídeos/metabolismo , RNA/metabolismo , Montagem de Vírus
13.
Food Chem ; 381: 132194, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35101706

RESUMO

Matrix complexity of fruit juices and their low antimony level requires sensitive, cost-effective instruments, time-consuming and error-prone sample pretreatment methods. Therefore, a flow-batch procedure (HG-FBA-AFS) was developed for the fast and sensitive determination of total inorganic Sb in grape juice samples by hydride generation atomic fluorescence spectrometry. The sample pretreatment, pre-reduction and stibine formation steps run through the mixing chamber. The HCl and NaBH4 concentrations, and carrier gas flowrate were optimized through a Box-Behnken design. The detection limit (LOD) was 20 ng L-1, intra and inter-day precision ranged in 3.0 - 3.5 %, and low errors within (- 2.4 to 6.6 %) for samples containing 1.23 - 4.58 µg L-1 total Sb. Both HG-FBA-AFS and reference method agreed at 95% confidence level. An 87 h-1 sample throughput, and a 1.15 mL total waste per determination attest that HG-FBA-AFS is a fast, and ecofriendly tool for determining Sb in grape juices.


Assuntos
Antimônio , Vitis , Antimônio/análise , Sucos de Frutas e Vegetais/análise , Espectrometria de Fluorescência/métodos , Espectrofotometria Atômica
14.
Medicine (Baltimore) ; 100(8): e24864, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33663110

RESUMO

BACKGROUND: This study aimed to describe the effects of a 90-minute group-based constraint-induced movement therapy protocol (CIMT) on upper extremity (UE) rehabilitation in poststroke patients. METHOD: The study was a case series clinical study with 6 patients with chronic stroke admitted to the institutional integrated clinic. Ten 90-minute CIMT sessions were administered, based on the principles of the original therapy. On completion of the protocol, participants underwent group care once a week, for 1 hour a day. For comparison purposes, the Wolf Motor Function Test (WMFT), Motor Activity Log (MAL), and Canadian Occupational Performance Measure (COPM) were applied on admission, shortly after completing the protocol, and 3 months after completion. In addition, the MAL and shaping tasks were applied daily. RESULTS: There was a statistically significant difference only in the MAL Amount of Use Scale applied daily between the 2nd (3.56) and 9th (3.31) and 2nd and 10th days (4.49) (P = .004), with a moderate effect size (d' = 0.46), and in the average value of shaping repetitions between the 1st (16.10) and 2nd (6.00) and 1st and 10th tasks (7.00) (P = .014), with a moderate effect size (d' = 0.35). CONCLUSION: The 90-minute CIMT protocol resulted in significant improvements in use of the more affected arm in activities of daily living during the 2-week protocol. Additional research with a larger sample and a control group is needed to confirm its effectiveness.


Assuntos
Terapia por Exercício/métodos , Terapia Ocupacional/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
15.
Diabetol Metab Syndr ; 12: 60, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32684985

RESUMO

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) has been increasing rapidly. It is nowadays recognized as the most frequent liver disease, affecting a quarter of global population and regularly coexisting with metabolic disorders such as type 2 diabetes, hypertension, obesity, and cardiovascular disease. In a more simplistic view, NAFLD could be defined as an increase in liver fat content, in the absence of secondary cause of steatosis. In fact, the clinical onset of the disease is a much more complex process, closely related to insulin resistance, limited expandability and dysfunctionality of adipose tissue. A fatty liver is a main driver for a new recognized liver-pancreatic α-cell axis and increased glucagon, contributing to diabetes pathophysiology. MAIN TEXT: This review will focus on the clinical and pathophysiological connections between NAFLD, insulin resistance and type 2 diabetes. We reviewed non-invasive methods and several scoring systems for estimative of steatosis and fibrosis, proposing a multistep process for NAFLD evaluation. We will also discuss treatment options with a more comprehensive view, focusing on the current available therapies for obesity and/or type 2 diabetes that impact each stage of NAFLD. CONCLUSION: The proper understanding of NAFLD spectrum-as a continuum from obesity to metabolic syndrome and diabetes-may contribute to the early identification and for establishment of targeted treatment.

16.
An Acad Bras Cienc ; 92 Suppl 1: e20180062, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32725068

RESUMO

Intraspecies or interspecies crossings transfer relevant alleles between plants. However, some interspecies crossings involving Passiflora species impede ovule fertilization and the viable development of seeds. Thus, the purpose of this study was to verify the viability of interspecific crossings and monitor pollen tube development. The experiment had six species of Passiflora in the reciprocal crossings. Histochemical tests aimed to evaluate the percentage of intraspecies or interspecies crossings that resulted in fruit development and pollen tube development. Ovule fertilization and fruit development occurred in determined directions of crossings when controlling the female or male genitor, but only one case of reciprocal crossing had success. In crossings with no fruit development, histological analysis showed that some callus developed in the stigma and style, confirming unilateral and interspecies incompatibility in the genus Passiflora to some species and some directions of crossings.


Assuntos
Passiflora , Flores , Óvulo Vegetal , Pólen , Polinização
17.
Clin Exp Pharmacol Physiol ; 47(7): 1272-1282, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31997362

RESUMO

Epidemiological and animal studies have demonstrated a strong association between selenium (Se) supplementation and metabolic disorders, we aimed to evaluate whether maternal Se supplementation was able to change metabolic parameters in rats' offspring. Moreover, as Se is a deiodinase (DIO) cofactor, we decided to investigate how thyroid hormones (THs) would be involved in such metabolic changes. Thereby, two groups (n = 6, ~250 g) of female Wistar rats underwent isotonic saline or sodium selenite (1 mg/kg, p.o.) treatments. Although there were no significant differences in body weight between groups, the Se treatment during pregnancy and lactation increased milk intake and the visceral white adipose tissue (WAT) in offspring. The rats whose mothers were treated with Se also presented an improvement in the glucose tolerance test and in the glucose-stimulated insulin secretion. Regarding the lipid metabolism, the Se group had a reduction of triglycerides in the liver and in WAT. These metabolic changes were accompanied by an increase in serum triiodothyronine (T3 ) and in DIO 2 expression in brown adipose tissue (BAT). We further demonstrate an increased expression of peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) and nuclear respiratory factor-1 (NRF-1) mRNA in the liver. In adulthood offspring, Se supplementation programs thyroid function, glucose homeostasis, and feeding behaviour. Taken together, there is no indication that Se programming causes insulin resistance. Moreover, we conjecture that these metabolic responses are induced by increased thyroxine (T4 ) to T3 conversion by DIO2 in BAT and mediated by altered transcription factors expression associated with oxidative metabolism control in the liver.


Assuntos
Suplementos Nutricionais/análise , Lactação/efeitos dos fármacos , Metabolismo/efeitos dos fármacos , Selênio/farmacologia , Animais , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar
18.
Talanta ; 207: 119834, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594561

RESUMO

In this paper, a flow-batch analysis (FBA) system, hydride generation (HG), and atomic fluorescence spectrometry (AFS) are coupled for the first time to develop a fast and sensitive FBA-HG-AFS method for automated inorganic antimony speciation in waters, whether from the sea, mineral water, tap water, or lakes. Unlike previous automated flow methods that use confluent fluids and complex devices, the main advantage of the proposed FBA-HG-AFS method is an innovative use of a simple laboratory made flow-batch chamber to simultaneously perform mixing, homogenization, reactions, antimony hydride formation, and gas-liquid separation. The FBA-HG-AFS method was optimized using two-level full factorial and Box-Behnken designs, and validated on the basis of real repeated measurements and analysis of variance, yielding a satisfactory working range (100-2000 ng L-1), precision (RSD = 4%), sensitivity, and limit of detection (6 ng L-1) for the water samples analyzed. Accuracy was evaluated by recovery tests and analysis of a standard reference material (SRM 1643e) of trace elements in water (NIST, USA), resulting in recovery rates of from 90 to 114%, and relative error = 0.7%. The high sampling throughput (54 speciations h-1), together with low waste generation, low costs, low reagent and sample consumption make this FBA-HG-AFS method an interesting proposal for fast large-scale analysis in routine laboratoy according to the principles of green analytical chemistry.

19.
Mar Environ Res ; 153: 104794, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31582297

RESUMO

Impacts of the interactive effects of ocean acidification (OA) with other anthropogenic environmental stressors on marine biodiversity are receiving increasing attention in recent years. However, little is known about how organismal responses to OA may be influenced by common phenomena such as autotomy and sexual dimorphism. This study evaluated the long-term (120 days) combined effects of OA (pH 7.7), experimental cheliped amputation and sex on physiological stress (mortality, growth, number of molts, cheliped regeneration and startle response) and energy budget (lipid and calcium contents) in the intertidal sexually-dimorphic hermit crab Pagurus criniticornis. Crabs exposed to OA reduced survivorship (46%), molting frequency (36%) and lipid content (42%). Autotomised crabs and males molted more frequently (39% and 32%, respectively). Males presented higher regeneration (33%) and lower lipid content (24%). The few synergistic effects recorded did not indicate any clear pattern among treatments however, (1) a stronger reduction in lipid content was recorded in non-autotomised crabs exposed to low pH; (2) calcium content was higher in males than females only for autotomised crabs under control pH; and (3) autotomised females showed a proportionally slower activity recovery than autotomised males. Although our results suggest an effect of long-term exposure to low pH on the physiological stress and energy budget of Pagurus criniticornis, the physiological repertoire and plasticity associated with limb regeneration and the maintenance of dimorphism in secondary sexual characters may provide resilience to long-term exposure to OA.

20.
Mar Environ Res ; 153: 104841, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31757479

RESUMO

The impacts of ocean acidification remain less well-studied in starfish compared to other echinoderm groups. This study examined the combined effects of elevated pCO2 and arm regeneration on the performance of the intertidal predatory starfish Asterias rubens, as both are predicted to come at a cost to the individual. A two-way factorial experiment (~400 µatm vs ~1000 µatm; autotomised vs non-automised individuals) was used to examine growth rates, lipid content (pyloric caeca and gonads), and calcium content (body wall) in both intact and regenerating arms, as well as subsequent effects on rate of arm regeneration, righting time (behaviour) and mortality over 120 days. Autotomised individuals tended to show lower (not significant), survival and growth. Elevated pCO2 had no effect on mortality, body growth, arm regeneration, righting time or arm calcium content. Lipid content was higher in the pyloric caeca, but not in the gonads, in response to elevated pCO2 irrespective of autotomisation. The results of the study suggest that adult A. rubens remain unaffected by increased pCO2 and/or arm autotomy for 120 days, although longer term experiments are necessary as the results indicated that survival, growth and calcification may be impaired with longer-term exposure to elevated pCO2.

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