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1.
J Biol Chem ; 300(3): 105767, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367672

RESUMEN

Approximately 5 to 15% of nonmedullary thyroid cancers (NMTC) present in a familial form (familial nonmedullary thyroid cancers [FNMTC]). The genetic basis of FNMTC remains largely unknown, representing a limitation for diagnostic and clinical management. Recently, germline mutations in DNA repair-related genes have been described in cases with thyroid cancer (TC), suggesting a role in FNMTC etiology. Here, two FNMTC families were studied, each with two members affected with TC. Ninety-four hereditary cancer predisposition genes were analyzed through next-generation sequencing, revealing two germline CHEK2 missense variants (c.962A > C, p.E321A and c.470T > C, p.I157T), which segregated with TC in each FNMTC family. p.E321A, located in the CHK2 protein kinase domain, is a rare variant, previously unreported in the literature. Conversely, p.I157T, located in CHK2 forkhead-associated domain, has been extensively described, having conflicting interpretations of pathogenicity. CHK2 proteins (WT and variants) were characterized using biophysical methods, molecular dynamics simulations, and immunohistochemistry. Overall, biophysical characterization of these CHK2 variants showed that they have compromised structural and conformational stability and impaired kinase activity, compared to the WT protein. CHK2 appears to aggregate into amyloid-like fibrils in vitro, which opens future perspectives toward positioning CHK2 in cancer pathophysiology. CHK2 variants exhibited higher propensity for this conformational change, also displaying higher expression in thyroid tumors. The present findings support the utility of complementary biophysical and in silico approaches toward understanding the impact of genetic variants in protein structure and function, improving the current knowledge on CHEK2 variants' role in FNMTC genetic basis, with prospective clinical translation.


Asunto(s)
Quinasa de Punto de Control 2 , Síndromes Neoplásicos Hereditarios , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Humanos , Quinasa de Punto de Control 2/química , Quinasa de Punto de Control 2/genética , Quinasa de Punto de Control 2/metabolismo , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Síndromes Neoplásicos Hereditarios/genética , Estudios Prospectivos , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Dominios Proteicos , Masculino , Femenino , Persona de Mediana Edad
2.
Clin Exp Pharmacol Physiol ; 51(3): e13837, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38302081

RESUMEN

Although it is well established that fibromyalgia (FM) syndrome is characterized by chronic diffuse musculoskeletal hyperalgesia, very little is known about the effect of this pathology on muscle tissue plasticity. Therefore, the present study aimed to characterize the putative alterations in skeletal muscle mass in female rats subjected to a FM model by inducing chronic diffuse hyperalgesia (CDH) through double injections of acidic saline (pH 4.0) into the left gastrocnemius muscle at 5-day intervals. To determine protein turnover, the total proteolysis, proteolytic system activities and protein synthesis were evaluated in oxidative soleus muscles of pH 7.2 (control) and pH 4.0 groups at 7 days after CDH induction. All animals underwent behavioural analyses of mechanical hyperalgesia, strength and motor performance. Our results demonstrated that, in addition to hyperalgesia, rats injected with acidic saline exhibited skeletal muscle loss, as evidenced by a decrease in the soleus fibre cross-sectional area. This muscle loss was associated with increased proteasomal proteolysis and expression of the atrophy-related gene (muscle RING-finger protein-1), as well as reduced protein synthesis and decreased protein kinase B/S6 pathway activity. Although the plasma corticosterone concentration did not differ between the control and pH 4.0 groups, the removal of the adrenal glands attenuated hyperalgesia, but it did not prevent the increase in muscle protein loss in acidic saline-injected animals. The data suggests that the stress-related hypothalamic-pituitary-adrenal axis is involved in the development of hyperalgesia, but is not responsible for muscle atrophy observed in the FM model induced by intramuscular administration of acidic saline. Although the mechanisms involved in the attenuation of hyperalgesia in rats injected with acidic saline and subjected to adrenalectomy still need to be elucidated, the results found in this study suggest that glucocorticoids may not represent an effective therapeutic approach to alleviate FM symptoms.


Asunto(s)
Fibromialgia , Hiperalgesia , Ratas , Femenino , Animales , Hiperalgesia/tratamiento farmacológico , Fibromialgia/complicaciones , Fibromialgia/tratamiento farmacológico , Fibromialgia/patología , Adrenalectomía , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipotálamo-Hipofisario/patología , Sistema Hipófiso-Suprarrenal/metabolismo , Sistema Hipófiso-Suprarrenal/patología , Músculo Esquelético/metabolismo , Atrofia Muscular/patología , Solución Salina/farmacología
3.
Haemophilia ; 29(2): 411-422, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36097135

RESUMEN

INTRODUCTION: Debilitating clinical complications in von Willebrand disease (VWD) can affect health-related quality of life (HRQoL), increase healthcare costs and cause long-lasting consequences. However, the magnitude of these burdens needs to be more fully explored. AIM: To estimate the prevalence and burden of clinical complications, the impact on HRQoL and the economic burden associated with VWD. METHODS: Embase® , MEDLINE® , the Cochrane Library and conference proceedings were searched for studies on VWD evaluating clinical complications, HRQoL and cost and resource use. RESULTS: Among 16 studies assessing clinical complications in VWD, the most prevalent bleeding symptoms were menorrhagia (2%-95% [n = 7 studies]), epistaxis (12%-80% [n = 6]) and easy bruising (46%-65% [n = 2]). Among 17 studies evaluating HRQoL, the most common assessment scales were the generic SF-36 (n = 8 studies) and the EQ-5D (n = 2). Bleeding symptoms were associated with reduced QoL in six of seven studies, and of six studies evaluating treatment impact, four reported improvements in one or more HRQoL components. Among 25 studies on cost and resource use, key observations included higher post-surgery healthcare costs in VWD versus non-VWD patients (n = 1 study) and higher costs and resource use in VWD patients with bleeding complications versus those without (n = 1). CONCLUSION: Although limited, available evidence suggests that VWD patients experience a high burden of clinical complications, reduced QoL and high healthcare costs. Haemarthrosis is more common in severe VWD than is often assumed, and bleeds (including haemarthrosis) can reduce QoL. Research efforts to improve QoL and other outcomes should be prioritized.


Asunto(s)
Menorragia , Enfermedades de von Willebrand , Femenino , Humanos , Adulto , Niño , Enfermedades de von Willebrand/complicaciones , Enfermedades de von Willebrand/epidemiología , Enfermedades de von Willebrand/diagnóstico , Hemartrosis/complicaciones , Calidad de Vida , Menorragia/complicaciones , Epistaxis , Factor de von Willebrand/uso terapéutico
4.
Haemophilia ; 29(4): 1087-1094, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37347645

RESUMEN

INTRODUCTION: Head-to-head evaluation of valoctocogene roxaparvovec, the first gene therapy approved for haemophilia A, with emicizumab is not available. Therefore, phase 3 trial data were indirectly compared. AIM: To compare bleeding rates in trials evaluating 6 × 1013  vg/kg valoctocogene roxaparvovec (GENEr8-1; NCT03370913), 1.5 mg/kg emicizumab dosed every week (HAVEN 3; NCT02847637), and FVIII prophylaxis (270-902) in participants with severe haemophilia A (FVIII ≤1 IU/dL). METHODS: Valoctocogene roxaparvovec versus emicizumab and FVIII prophylaxis as used in 270-902 versus emicizumab cross-trial comparisons were performed using matching-adjusted indirect comparison (MAIC). Individual participant data from GENEr8-1 and 270-902 were weighted to equalise aggregate participant baseline characteristics from HAVEN 3. After MAIC weighting, annualised bleeding rates (ABR) and proportions of participants without bleeds were compared for treated bleeds, all bleeds, treated joint bleeds, and treated spontaneous bleeds. RESULTS: After MAIC weighting, ABR for all bleeds was statistically significantly lower with valoctocogene roxaparvovec than emicizumab (rate ratio [95% CI], .55 [.33-.93]). Additionally, significantly higher proportions of participants had no treated joint bleeds (odds ratio [95% CI], 2.75 [1.20-6.31]) and no treated bleeds (3.25 [1.53-6.90]) with valoctocogene roxaparvovec versus emicizumab. When compared with the mainly standard half-life FVIII prophylaxis regimens in 270-902, mean ABRs (except for all bleeds) were significantly lower, and significantly higher proportions reported 0 bleeds for all outcomes with emicizumab. CONCLUSION: Valoctocogene roxaparvovec provided generally lower bleeding rates and higher probability of no bleeds, including treated joint bleeds, than emicizumab. Emicizumab was more effective than FVIII prophylaxis regimens used in 270-902.


Asunto(s)
Anticuerpos Biespecíficos , Hemofilia A , Humanos , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Factor VIII/genética , Factor VIII/uso terapéutico , Terapia Genética , Hemartrosis/tratamiento farmacológico , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Hemorragia/etiología , Hemorragia/prevención & control , Hemorragia/tratamiento farmacológico
5.
An Acad Bras Cienc ; 95(suppl 1): e20220514, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37493694

RESUMEN

Different degrees in the biological activities of Canavalia rosea had been previously reported . In this study, our group assessed the cardioprotective effects of the ethyl acetate fraction (EAcF) of the Canavalia rosea leaves. Firstly, it was confirmed, by in vitro approach, that the EAcF has high antioxidant properties due to the presence of important secondary metabolites, as flavonoids. In order to explore their potential protector against cardiovascular disorders, hearts were previously perfused with EAcF (300 µg.mL-1) and submitted to the global ischemia followed by reperfusion in Langendorff system. The present findings have demonstrated that EAcF restored the left ventricular developed pressure and decreased the arrhythmias severity index. Furthermore, EAcF significantly increased the glutathiones peroxidase activity with decreased malondialdehyde and creatine kinase levels. EAcF was effective upon neither the superoxide dismutase, glutationes reductase nor the catalase activities. In addition, the Western blot analysis revealed that ischemia-reperfusion injury significantly upregulates caspase 3 protein expression, while EAcF abolishes this effect. These results provide evidence that the EAcF reestablishes the cardiac contractility and prevents arrhythmias; it is suggested that EAcF could be used to reduce injury caused by cardiac reperfusion. However more clinical studies should be performed, before applying it in the clinic.


Asunto(s)
Antioxidantes , Daño por Reperfusión Miocárdica , Ratas , Animales , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Canavalia/metabolismo , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , Hojas de la Planta/metabolismo , Miocardio/metabolismo
6.
BMC Med Educ ; 23(1): 731, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37803431

RESUMEN

BACKGROUND: Patients who have short peripheral venous catheters (PVC) face an elevated risk of developing bloodstream infections. Preventing catheter-related infections relies on implementing multiple measures, including practicing proper hand hygiene (HH) during catheter placement. METHODS: We conducted a four-part study: (1) an evaluation of HH practices through direct observation of PVC placements, coupled with the study of the microbial flora of the HCWs fingers just before the placement; (2) the development of an educational tool based on the collected observational and microbiological data; (3) the training to the HCWs observed during the first part, using this tool; and (4) the subsequent observation of the trained HCWs to measure the impact of the training on practice improvement. RESULTS: Compliant HH was observed in 23.5% of the 647 HCWs observed during PVC placement before training. The microbiological study revealed fewer pathogens on the fingertips of the HCWs practicing compliant HH compared other HCWs (2.6 vs 11,7%; p = 0.003). The comparison of practices before and after training, assessed among 180 HCWs, showed an increase in the proportion of HCWs performing compliant HH (25.0 vs 63.2%; p < 0.001). CONCLUSIONS: Training HCWs using our educational tool, which combines reminders of best practices and risk factors associated with PVC-related infections, engaging HCWs (presentation of practice evaluation), identifying professionals deviating from best practices (simulation videos), and objectively assessing fingertip contamination (microbiological study), significantly improved compliance with HH gestures and glove usage. We encourage infection control teams to utilize this tool to raise awareness among HCWs responsible for PVC placement about the risk of infection associated inadequate hand hygiene.


Asunto(s)
Infección Hospitalaria , Higiene de las Manos , Humanos , Infección Hospitalaria/prevención & control , Control de Infecciones , Higiene , Adhesión a Directriz , Catéteres , Personal de Salud/educación
7.
Proc Natl Acad Sci U S A ; 116(12): 5727-5736, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30808806

RESUMEN

Homeostatic synaptic scaling is a negative feedback response to fluctuations in synaptic strength induced by developmental or learning-related processes, which maintains neuronal activity stable. Although several components of the synaptic scaling apparatus have been characterized, the intrinsic regulatory mechanisms promoting scaling remain largely unknown. MicroRNAs may contribute to posttranscriptional control of mRNAs implicated in different stages of synaptic scaling, but their role in these mechanisms is still undervalued. Here, we report that chronic blockade of glutamate receptors of the AMPA and NMDA types in hippocampal neurons in culture induces changes in the neuronal mRNA and miRNA transcriptomes, leading to synaptic upscaling. Specifically, we show that synaptic activity blockade persistently down-regulates miR-186-5p. Moreover, we describe a conserved miR-186-5p-binding site within the 3'UTR of the mRNA encoding the AMPA receptor GluA2 subunit, and demonstrate that GluA2 is a direct target of miR-186-5p. Overexpression of miR-186 decreased GluA2 surface levels, increased synaptic expression of GluA2-lacking AMPA receptors, and blocked synaptic scaling, whereas inhibition of miR-186-5p increased GluA2 surface levels and the amplitude and frequency of AMPA receptor-mediated currents, and mimicked excitatory synaptic scaling induced by synaptic inactivity. Our findings elucidate an activity-dependent miRNA-mediated mechanism for regulation of AMPA receptor expression.


Asunto(s)
MicroARNs/genética , Neuronas/metabolismo , Receptores AMPA/genética , Regiones no Traducidas 3' , Animales , Células Cultivadas , Potenciales Postsinápticos Excitadores/fisiología , Células HEK293 , Hipocampo/metabolismo , Homeostasis , Humanos , MicroARNs/metabolismo , Plasticidad Neuronal/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Receptores AMPA/metabolismo , Receptores AMPA/fisiología , Sinapsis/metabolismo
8.
Proc Natl Acad Sci U S A ; 116(30): 15253-15261, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31285343

RESUMEN

Because the white matter of the cerebral cortex contains axons that connect distant neurons in the cortical gray matter, the relationship between the volumes of the 2 cortical compartments is key for information transmission in the brain. It has been suggested that the volume of the white matter scales universally as a function of the volume of the gray matter across mammalian species, as would be expected if a global principle of wiring minimization applied. Using a systematic analysis across several mammalian clades, here we show that the volume of the white matter does not scale universally with the volume of the gray matter across mammals and is not optimized for wiring minimization. Instead, the ratio between volumes of gray and white matter is universally predicted by the same equation that predicts the degree of folding of the cerebral cortex, given the clade-specific scaling of cortical thickness, such that the volume of the gray matter (or the ratio of gray to total cortical volumes) divided by the square root of cortical thickness is a universal function of total cortical volume, regardless of the number of cortical neurons. Thus, the very mechanism that we propose to generate cortical folding also results in compactness of the white matter to a predictable degree across a wide variety of mammalian species.


Asunto(s)
Corteza Cerebral/anatomía & histología , Sustancia Gris/anatomía & histología , Neuronas/citología , Sustancia Blanca/anatomía & histología , Animales , Artiodáctilos/anatomía & histología , Artiodáctilos/fisiología , Corteza Cerebral/citología , Corteza Cerebral/fisiología , Conectoma , Sustancia Gris/citología , Sustancia Gris/fisiología , Humanos , Neuronas/fisiología , Tamaño de los Órganos/fisiología , Especificidad de Órganos , Primates/anatomía & histología , Primates/fisiología , Roedores/anatomía & histología , Roedores/fisiología , Escandentios/anatomía & histología , Escandentios/fisiología , Sustancia Blanca/citología , Sustancia Blanca/fisiología
9.
Molecules ; 27(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36144765

RESUMEN

One of the most widely used molecules used for photodynamic therapy (PDT) is 5-aminolevulinic acid (5-ALA), a precursor in the synthesis of tetrapyrroles such as chlorophyll and heme. The 5-ALA skin permeation is considerably reduced due to its hydrophilic characteristics, decreasing its local bioavailability and therapeutic effect. For this reason, five different systems containing polymeric particles of poly [D, L-lactic-co-glycolic acid (PLGA)] were developed to encapsulate 5-ALA based on single and double emulsions methodology. All systems were standardized (according to the volume of reagents and mass of pharmaceutical ingredients) and compared in terms of laboratory scaling up, particle formation and stability over time. UV-VIS spectroscopy revealed that particle absorption/adsorption of 5-ALA was dependent on the method of synthesis. Different size distribution was observed by DLS and NTA techniques, revealing that 5-ALA increased the particle size. The contact angle evaluation showed that the system hydrophobicity was dependent on the surfactant and the 5-ALA contribution. The FTIR results indicated that the type of emulsion influenced the particle formation, as well as allowing PEG functionalization and interaction with 5-ALA. According to the 1H-NMR results, the 5-ALA reduced the T1 values of polyvinyl alcohol (PVA) and PLGA in the double emulsion systems due to the decrease in molecular packing in the hydrophobic region. The results indicated that the system formed by single emulsion containing the combination PVA-PEG presented greater stability with less influence from 5-ALA. This system is a promising candidate to successfully encapsulate 5-ALA and achieve good performance and specificity for in vitro skin cancer treatment.


Asunto(s)
Ácido Aminolevulínico , Ácido Poliglicólico , Clorofila , Emulsiones , Hemo , Ácido Láctico/química , Tamaño de la Partícula , Polietilenglicoles/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Alcohol Polivinílico/química , Tensoactivos , Tetrapirroles
10.
Public Health Nurs ; 39(4): 752-759, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34935199

RESUMEN

OBJECTIVE: There is still a lack of health indicators for monitoring and evaluating health planning at the local level. In Portugal, local health plans (LHP) include a prioritized set of health priorities, which should be monitored and evaluated. This study is an example of a low-resource method to identify and reuse indicators for LHP monitoring and evaluation already collected for other purposes. DESIGN AND SAMPLE: A modified Delphi consensus method was applied, with three rounds of email rating questionnaires and a final meeting, between January 2018 and January 2019. The Delphi panel consisted of eight members from the Planning and Administration Group of the Espinho/Gaia Local Public Health Unit. MEASUREMENTS: Panelists were asked to assess the indicators' validity for monitoring diseases/determinants from a pre-selected list of potential binomials between 140 PHC indicators and 15 diseases/determinants. RESULTS: After four rounds, there was consensus in considering 141 binomials (34.0%) as appropriate, diabetes mellitus being the disease with more appropriate indicators. CONCLUSION: This study portrays the applicability of a commonly used, easy and low-resource method in a Portuguese Local Public Health Unit to select and reuse primary health care indicators for LHP monitoring and evaluation.


Asunto(s)
Planificación en Salud , Indicadores de Calidad de la Atención de Salud , Consenso , Técnica Delphi , Humanos , Encuestas y Cuestionarios
11.
J Neurosci ; 40(24): 4622-4643, 2020 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-32253358

RESUMEN

Microglial cells play essential volume-related actions in the brain that contribute to the maturation and plasticity of neural circuits that ultimately shape behavior. Microglia can thus be expected to have similar cell sizes and even distribution both across brain structures and across species with different brain sizes. To test this hypothesis, we determined microglial cell densities (the inverse of cell size) using immunocytochemistry to Iba1 in samples of free cell nuclei prepared with the isotropic fractionator from brain structures of 33 mammalian species belonging to males and females of five different clades. We found that microglial cells constitute ∼7% of non-neuronal cells in different brain structures as well as in the whole brain of all mammalian species examined. Further, they vary little in cell density compared with neuronal cell densities within the cerebral cortex, across brain structures, across species within the same clade, and across mammalian clades. As a consequence, we find that one microglial cell services as few as one and as many as 100 neurons in different brain regions and species, depending on the local neuronal density. We thus conclude that the addition of microglial cells to mammalian brains is governed by mechanisms that constrain the size of these cells and have remained conserved over 200 million years of mammalian evolution. We discuss the probable consequences of such constrained size for brain function in health and disease.SIGNIFICANCE STATEMENT Microglial cells are resident macrophages of the CNS, with key functions in recycling synapses and maintaining the local environment in health and disease. We find that microglial cells occur in similar densities in the brains of different species and in the different structures of each individual brain, which indicates that these cells maintain a similar average size in mammalian evolution, suggesting in turn that the volume monitored by each microglial cell remains constant across mammals. Because the density of neurons is highly variable across the same brain structures and species, our finding implies that microglia-dependent functional recovery may be particularly difficult in those brain structures and species with high neuronal densities and therefore fewer microglial cells per neuron.


Asunto(s)
Encéfalo/citología , Microglía/citología , Animales , Evolución Biológica , Recuento de Células , Femenino , Masculino , Mamíferos , Especificidad de la Especie
12.
Epidemiol Infect ; 149: e185, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34338185

RESUMEN

This study aimed to analyse the geographical distribution of coronavirus disease 2019 (COVID-19) and to identify high-risk areas in space and time for the occurrence of cases and deaths in the indigenous population of Brazil. This is an ecological study carried out between 24 March and 26 October 2020 whose units of analysis were the Special Indigenous Sanitary Districts. The Getis-Ord General G and Getis-Ord Gi* techniques were used to verify the spatial association of the phenomena and a retrospective space-time scan was performed. There were 32 041 confirmed cases of COVID-19 and 471 deaths. The non-randomness of cases (z score = 5.40; P < 0.001) and deaths (z score = 3.83; P < 0.001) were confirmed. Hotspots were identified for cases and deaths in the north and midwest regions of Brazil. Sixteen high-risk space-time clusters were identified for the occurrence of cases with a higher RR = 21.23 (P < 0.001) and four risk clusters for deaths with a higher RR = 80.33 (P < 0.001). These clusters were identified from 22 May and were active until 10 October 2020. The results indicate critical areas in the indigenous territories of Brazil and contribute to better directing the actions of control of COVID-19 in this population.


Asunto(s)
COVID-19/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , COVID-19/mortalidad , COVID-19/virología , Niño , Preescolar , Femenino , Humanos , Indígenas Sudamericanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Factores Sexuales , Adulto Joven
13.
Bioorg Chem ; 110: 104786, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33740676

RESUMEN

Studies displaying the combination of mefloquine (MFL) with anti-tuberculosis (TB) substances are limited in the literature. In this work, the effect of MFL-association with two first-line anti-TB drugs and six fluoroquinolones was evaluated against Mycobacterium tuberculosis drug resistant strains. MFL showed synergistic interaction with isoniazid, pyrazinamide, and several fluoroquinolones, reaching fractional inhibitory concentration indexes (FICIs) ranging from 0.03 to 0.5. In order to better understand the observed results, two approaches have been explored: (i) spectroscopic responses attributed to the effect of MFL on physicochemical properties related to a liposomal membrane model composed by soybean asolectin; (ii) molecular dynamics (MD) simulation data regarding MFL interaction with a membrane model based on PIM2, a lipid constituent of the mycobacterial cell wall. FTIR and NMR data showed that MFL affects expressively the region between the phosphate and the first methylene groups of soybean asolectin membranes, disordering these regions. MD simulations results detected high MFL density in the glycolipid interface and showed that the drug increases the membrane lateral diffusion, enhancing its permeability. The obtained results suggest that synergistic activities related to MFL are attributed to its effect of lipid disorder and membrane permeability enhancement.


Asunto(s)
Antituberculosos/farmacología , Mefloquina/farmacología , Simulación de Dinámica Molecular , Mycobacterium tuberculosis/efectos de los fármacos , Antituberculosos/síntesis química , Antituberculosos/química , Relación Dosis-Respuesta a Droga , Espectroscopía de Resonancia Magnética , Mefloquina/síntesis química , Mefloquina/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Isótopos de Fósforo , Espectroscopía Infrarroja por Transformada de Fourier , Relación Estructura-Actividad
14.
An Acad Bras Cienc ; 93(suppl 4): e20210222, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34909827

RESUMEN

This study evaluated the ability of resistance training (RT) of moderate intensity to promote vascular changes in insulin-induced vasodilation in healthy animals. Wistar rats were divided into two groups: control (CON) and trained (eight weeks of training, performing 3 sets with 10 repetitions at 60% of maximum intensity). Forty-eight hours after the last session of the RT, the animals were sacrificed and vascular reactivity to insulin in the absence and presence of LY294002 (phosphatidylinositol 3-kinase inhibitors (PI3K), L-NAME (nitric oxide synthase (NOS) inhibitors) and BQ123 (endothelin A antagonist (ET-A) receptor). In addition, phenylephrine (Phe)-induced vasoconstriction in the absence and presence of L-NAME was also evaluated. The RT group showed greater vasodilation in maximal response compared to the CON group. After PI3K inhibition, vasodilation was reduced in both groups. However, when the NOS participation was evaluated, the RT group showed contraction in relation to the CON group, which was abolished by BQ123. In addition, the RT group had an increase in nitrite levels compared to the CON group. When the Phe response was evaluated, there was a reduction in tension in the RT group compared to the CON group. The results suggest that RT improves vascular reactivity.


Asunto(s)
Entrenamiento de Fuerza , Vasodilatación , Animales , Humanos , Insulina , Arterias Mesentéricas , Óxido Nítrico , Fosfatidilinositol 3-Quinasas , Inhibidores de las Quinasa Fosfoinosítidos-3 , Ratas , Ratas Wistar
15.
An Acad Bras Cienc ; 93(2): e20201604, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33852672

RESUMEN

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.


Asunto(s)
Biodiversidad , Ecosistema , Brasil , Conservación de los Recursos Naturales , Humanos , Conocimiento
16.
Trop Anim Health Prod ; 53(6): 525, 2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34709458

RESUMEN

Among the animal species first introduced in Brazil during the country's discovery, horses (Equus caballus) stand out because of their evolutionary history and relationship with humans. Among the Brazilian horse breeds, the Pantaneiro draws attention due to its adaptative traits. Blood samples of 116 Pantaneiro horses were divided into six populations based on their sampling location, aiming to identify the existence of genetic structure and quantify genetic diversity within and between them. Populations were compared to elucidate genetic variability and differentiation better and assess the impact of Pantanal's natural geographic barriers on gene flow between populations. Data from the GGP Equine BeadChip (Geneseek-Neogen, 65.157 SNPs) was used to assess basic diversity parameters, genetic distance (FST), principal component analysis (PCA), and population structure (ADMIXTURE) for the sampled animals. Mantel test was also performed to investigate the correlation between the populations' genetic and geographic distances. Results showed high genetic variability in all populations, with elevated levels of admixture in their structure. High levels of admixture make it challenging to establish a racial pattern and, consequently, populations within the breed, being that only one of the populations differentiated itself from the others. No significant correlations between genetic and geographic distances were observed, indicating that environmental barriers did not hinder gene flow between populations, and neither farmers' selection practices might have change breed genetic composition significantly. Low genetic distance and similar heterozygosity values were observed among populations, suggesting strong genetic proximity and low differentiation. Thereby, the Pantaneiro breed does not exhibit genetic subpopulations and could be considered, for conservation purposes, a single big population in the Panatnal region. This study will support sampling strategies for National genebank.


Asunto(s)
Variación Genética , Genética de Población , Animales , Brasil , Caballos/genética , Fenotipo , Polimorfismo de Nucleótido Simple
17.
Trop Anim Health Prod ; 53(1): 126, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33449218

RESUMEN

There are few animal germplasm/gene bank collections in Brazil, and basic studies are needed to attend the future internal and external demands from international partners. The aim of this work was to validate a "proof of concept" that integrates spatial (georeferenced data) and genetic data regarding the local of origin from 3518 DNA samples from 17 different genetic groups or breeds of sheep in the Brazilian Germplasm bank. Spatialisation shows that not all genetic groups have samples in the bank, and collection is concentrated in the conservation nuclei spread nationwide. Only 21% of states with a specific breed have samples in the gene bank. The mean number of animals sampled per collection was 32, while the mean distance travelled to collect samples was 262 km from the conservation nuclei. For example, the Brazilian Somali were only collected in the conservation nucleus in Ceará State. No samples were collected to date for the Cariri breed, which is recognised by the Brazilian Ministry of Agriculture. Only two farms and one breed in the bank are from the northern region. Of the 27 states, there are samples in the gene bank of sheep from 13, so several states have no samples, requiring collection from herds outside the official system of conservation to make sure that studies using this germplasm realised are not biased. Significant genetic differences are seen above 332 km, which should guide future sampling efforts. Suggestions are given for improving the quantity, quality and diversity of samples in the gene bank.


Asunto(s)
Biodiversidad , Cruzamiento , Variación Genética , Ovinos/genética , Agricultura , Animales , Bancos de Muestras Biológicas , Brasil , Conservación de los Recursos Naturales
18.
Circ Res ; 122(7): e49-e61, 2018 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-29467196

RESUMEN

RATIONALE: The MR (mineralocorticoid receptor) antagonists belong to the current therapeutic armamentarium for the management of cardiovascular diseases, but the mechanisms conferring their beneficial effects are poorly understood. Part of the cardiovascular effects of MR is because of the regulation of L-type Cav1.2 Ca2+ channel expression, which is generated by tissue-specific alternative promoters as a long cardiac or short vascular N-terminal transcripts. OBJECTIVE: To analyze the molecular mechanisms by which aldosterone, through MR, modulates Cav1.2 expression and function in a tissue-specific manner. METHODS AND RESULTS: In primary cultures of neonatal rat ventricular myocytes, aldosterone exposure for 24 hours increased in a concentration-dependent manner long cardiac Cav1.2 N-terminal transcripts expression at both mRNA and protein levels, correlating with enhanced concentration-, time-, and MR-dependent P1-promoter activity. In silico analysis and mutagenesis identified MR interaction with both specific activating and repressing DNA-binding elements on the P1-promoter. The relevance of this regulation is confirmed both ex and in vivo in transgenic mice harboring the luciferase reporter gene under the control of the cardiac P1-promoter. Moreover, we show that this cis-regulatory mechanism is not limited to the heart. Indeed, in smooth muscle cells from different vascular beds, in which the short vascular Cav1.2 N-terminal transcripts is normally the major isoform, we found that MR signaling activates long cardiac Cav1.2 N-terminal transcripts expression through P1-promoter activation, leading to vascular contractile dysfunction. These results were further corroborated in hypertensive aldosterone/salt rodent models, showing notably a positive correlation between blood pressure and cardiac P1-promoter activity in aorta. This new vascular long cardiac Cav1.2 N-terminal transcripts molecular signature reduced sensitivity to the Ca2+ channel blocker, nifedipine, in aldosterone-treated vessels. CONCLUSIONS: Our results reveal that MR acts as a transcription factor to translate aldosterone signal into specific cardiac P1-promoter activation that might influence the therapeutic outcome of cardiovascular diseases.


Asunto(s)
Canales de Calcio Tipo L/metabolismo , Miocitos Cardíacos/metabolismo , Regiones Promotoras Genéticas , Receptores de Mineralocorticoides/metabolismo , Activación Transcripcional , Aldosterona/farmacología , Animales , Canales de Calcio Tipo L/genética , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Miocitos Cardíacos/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Ratas , Ratas Wistar
19.
Eur J Clin Microbiol Infect Dis ; 39(11): 2185-2194, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32519215

RESUMEN

To increase the knowledge about S. capitis in the neonatal setting, we conducted a nationwide 3-month survey in 38 neonatal intensive care units (NICUs) covering 56.6% of French NICU beds. We demonstrated 14.2% of S. capitis BSI (S.capBSI) among nosocomial BSIs. S.capBSI incidence rate was 0.59 per 1000 patient-days. A total of 55.0% of the S.capBSIs were late onset catheter-related BSIs. The S. capitis strains infected preterm babies (median gestational age 26 weeks, median birth weight 855 g). They were resistant to methicillin and aminoglycosides and belonged to the NRCS-A clone. Evolution was favorable in all but one case, following vancomycin treatment.


Asunto(s)
Sepsis/epidemiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus capitis/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/etiología , Farmacorresistencia Bacteriana Múltiple , Femenino , Francia/epidemiología , Humanos , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Masculino , Sepsis/tratamiento farmacológico , Sepsis/etiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/etiología , Staphylococcus capitis/efectos de los fármacos
20.
Cereb Cortex ; 29(12): 4919-4931, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-30843029

RESUMEN

Neuropsychiatric disorders share susceptibility genes, suggesting a common origin. One such gene is CNTNAP2 encoding contactin-associated protein 2 (CASPR2), which harbours mutations associated to autism, schizophrenia, and intellectual disability. Antibodies targeting CASPR2 have also been recently described in patients with several neurological disorders, such as neuromyotonia, Morvan's syndrome, and limbic encephalitis. Despite the clear implication of CNTNAP2 and CASPR2 in neuropsychiatric disorders, the pathogenic mechanisms associated with alterations in CASPR2 function are unknown. Here, we show that Caspr2 is expressed in excitatory synapses in the cortex, and that silencing its expression in vitro or in vivo decreases the synaptic expression of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors and the amplitude of AMPA receptor-mediated currents. Furthermore, Caspr2 loss of function blocks synaptic scaling in vitro and experience-dependent homoeostatic synaptic plasticity in the visual cortex. Patient CASPR2 antibodies decrease the dendritic levels of Caspr2 and synaptic AMPA receptor trafficking, and perturb excitatory transmission in the visual cortex. These results suggest that mutations in CNTNAP2 may contribute to alterations in AMPA receptor function and homoeostatic plasticity, and indicate that antibodies from anti-CASPR2 encephalitis patients affect cortical excitatory transmission.


Asunto(s)
Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Plasticidad Neuronal/fisiología , Receptores AMPA/metabolismo , Transmisión Sináptica/fisiología , Anciano , Animales , Trastorno Autístico/genética , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Encefalitis/inmunología , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Ratas , Ratas Wistar , Corteza Visual/metabolismo
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