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1.
Eur J Nutr ; 63(4): 1163-1175, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38358514

RESUMO

PURPOSE: The present study aimed at evaluating possible synergistic effects between two risk factors for cognitive decline and neurodegenerative disorders, i.e. iron overload and exposure to a hypercaloric/hyperlipidic diet, on cognition, insulin resistance, and hippocampal GLUT1, GLUT3, Insr mRNA expression, and AKT phosporylation. METHODS: Male Wistar rats were treated with iron (30 mg/kg carbonyl iron) or vehicle (5% sorbitol in water) from 12 to 14th post-natal days. Iron-treated rats received a standard laboratory diet or a high fat diet from weaning to adulthood (9 months of age). Recognition and emotional memory, peripheral blood glucose and insulin levels were evaluated. Glucose transporters (GLUT 1 and GLUT3) and insulin signaling were analyzed in the hippocampus of rats. RESULTS: Both iron overload and exposure to a high fat diet induced memory deficits. Remarkably, the association of iron with the high fat diet induced more severe cognitive deficits. Iron overload in the neonatal period induced higher insulin levels associated with significantly higher HOMA-IR, an index of insulin resistance. Long-term exposure to a high fat diet resulted in higher fasting glucose levels. Iron treatment induced changes in Insr and GLUT1 expression in the hippocampus. At the level of intracellular signaling, both iron treatment and the high fat diet decreased AKT phosphorylation. CONCLUSION: The combination of iron overload with exposure to a high fat diet only led to synergistic deleterious effect on emotional memory, while the effects induced by iron and by the high fat diet on AKT phosphorylation were comparable. These findings indicate that there is, at least to some extent, an additive effect of iron combined with the diet. Further studies investigating the mechanisms associated to deleterious effects on cognition and susceptibility for the development of age-associated neurodegenerative disorders are warranted.


Assuntos
Animais Recém-Nascidos , Dieta Hiperlipídica , Transportador de Glucose Tipo 1 , Hipocampo , Resistência à Insulina , Sobrecarga de Ferro , Transtornos da Memória , Ratos Wistar , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/metabolismo , Transtornos da Memória/etiologia , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Ratos , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 3/metabolismo , Transportador de Glucose Tipo 3/genética , Receptor de Insulina/metabolismo , Receptor de Insulina/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicemia/metabolismo , Insulina/sangue , Transdução de Sinais
2.
J Morphol ; 283(10): 1299-1317, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35971644

RESUMO

The highly differentiated anuran larvae make them an interesting and complementary source of information to understand anuran evolution. Among neotropical foam-nesting frogs, the available information on tadpole morphology for the subfamily Leiuperinae remains largely incomplete and variably reported among genera; in the monophyletic genus Engystomops it is still incipient. Herein, we summarize available information on larval morphology for five of the nine known species of Engystomops, three of them for the first time, reporting external morphology, buccopharyngeal cavity, and skeleton. The tadpoles of the genus have an overall generalized morphology and many traits are conserved across species. Nevertheless, many characters are systematically informative and some are diagnostic for some species, as the paravertebral gland in Engystomops petersi and the dorsally directed spiracle in Engystomops puyango. Other characters provide support for some subclades within the genus. Moreover, some traits, such as the direction of the vent tube, supports the close relationship between Engystomops and Physalaemus, whereas other support the existence of these two as distinct genera, such as the overall shape of the lateral ridge papillae and the presence of a processus pseudopterygoideus.


Assuntos
Anuros , Animais , Anuros/anatomia & histologia , Brasil , Larva/anatomia & histologia , Filogenia
3.
J Morphol ; 282(1): 115-126, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078885

RESUMO

The genus Edalorhina consists of two species of small forest-floor frogs inhabiting the Amazon basin. The tadpole of Edalorhina perezi, the most widely distributed species, was previously described based on a single and early stage (Gosner 25) individual. Herein, we provide a description of the tadpole in Gosner stages 35-36 including internal morphology data (i.e., buccopharyngeal cavity and larval skeleton) based on samples from two populations from Ecuador. Edalorhina shares a generalized morphology with most members of its closely related taxa; however, it is distinguished from the other species by having an almost terminal oral disc. The presence of a dextral vent tube is considered a synapomorphy for the clade consisting of Edalorhina, Engystomops, and Physalaemus. Within this clade, the combination of two lingual papillae, a filiform median ridge, and the lack of buccal roof papillae are diagnostic of E. perezi and putative autapomorphies of Edalorhina. Chondrocranial anatomy provides characteristics, that is, presence of and uniquely shaped processus pseudopterygoideus and cartilago suprarostralis with corpora and alae joined by dorsal and ventral connections that readily differentiates the genus from other Leiuperinae.


Assuntos
Anuros/anatomia & histologia , Boca/anatomia & histologia , Crânio/anatomia & histologia , Animais , Brasil , Larva/anatomia & histologia , Larva/ultraestrutura , Boca/ultraestrutura , Filogenia , Crânio/ultraestrutura , Especificidade da Espécie
4.
J Gen Intern Med ; 35(12): 3613-3619, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32815055

RESUMO

OBJECTIVES: To assess the attitudes, knowledge, and experiences of Brazilian resident physicians regarding religiosity/spirituality (R/S), factors associated with addressing this issue, and its influence on clinical practice. METHODS: We report results of the multicenter "Spirituality in Brazilian Medical Residents" (SBRAMER) study involving 7 Brazilian university centers. The Network for Research Spirituality and Health (NERSH) scale (collecting sociodemographic data, opinions about the R/S-health interface, and respondents' R/S characteristics) and the Duke Religion Index were self-administered. Logistic regression models were constructed to determine those factors associated with residents' opinions on spirituality in clinical practice. RESULTS: The sample comprised 879 resident physicians (53.5% of total) from all years of residency with 71.6% from clinical specialties. In general, the residents considered themselves spiritual and religious, despite not regularly attending religious services. Most participants believed R/S had an important influence on patient health (75.2%) and that it was appropriate to discuss these beliefs in clinical encounters with patients (77.1%), although this was not done in routine clinical practice (14.4%). The main barriers to discussing R/S were maintaining professional neutrality (31.4%), concern about offending patients (29.1%), and insufficient time (26.2%). Factors including female gender, clinical specialty (e.g., internal medicine, family medicine, psychiatry) as opposed to surgical specialty (e.g., surgery, obstetrics/gynecology, orthopedics), having had formal training on R/S, and higher levels of R/S were associated with greater discussion of and more positive opinions about R/S. CONCLUSION: Brazilian resident physicians held that religious and spiritual beliefs can influence health, and deemed it appropriate for physicians to discuss this issue. However, lack of training was one of the main obstacles to addressing R/S issues in clinical practice. Educators should draw on these data to conduct interventions and produce content on the subject in residency programs.


Assuntos
Médicos , Espiritualidade , Brasil , Estudos Transversais , Feminino , Humanos , Religião , Inquéritos e Questionários
5.
Zootaxa ; 4732(2): zootaxa.4732.2.12, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32230269

RESUMO

The Neotropical foam-nesting genus Leptodactylus Fitzinger is currently composed of 75 species (Frost 2019) divided into four monophyletic species groups (De Sá et al. 2014). The L. melanonotus species group includes 17 species delimited by five adult osteological character-states (De Sá et al. 2014). Leptodactylus natalensis Lutz is the only species of the L. melanonotus species group that occurs in north of the Brazilian Atlantic Rain Forest (De Sá et al. 2014; Almeida et al. 2016) and whose type locality is the municipality of Natal, state of Rio Grande do Norte, Brazil (Lutz 1930). The tadpole of this species was briefly described by Oliveira Lírio-Júnior (2000) based on a single individual from the municipality of Aracaju, state of Sergipe, Brazil. Herein, we present a complete redescription of the tadpole of this species, including morphometric data and interpopulational variation. Besides, we provide comparisons with all members of the L. melanonotus group.


Assuntos
Anuros , Florestas , Animais , Brasil , Larva , Floresta Úmida
6.
Diabetol Metab Syndr ; 11: 78, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31558916

RESUMO

BACKGROUND: The enzyme 11-beta hydroxysteroid dehydrogenase type 1 (HSD11B1) converts inactive cortisone to active cortisol in a process mediated by the enzyme hexose-6-phosphate dehydrogenase (H6PD). The generation of cortisol from this reaction may increase intra-abdominal cortisol levels and contribute to the physiopathogenesis of obesity and metabolic syndrome (MetS). The relationship of HSD11B1 rs45487298 and H6PD rs6688832 polymorphisms with obesity and MetS was studied. We also studied how HSD11B1 abdominal subcutaneous (SAT) and visceral adipose tissue (VAT) gene expression is related to body fat distribution. METHODS: Rates of obesity and MetS features were cross-sectionally analyzed according to these polymorphisms in 1006 Brazilian white patients with type 2 diabetes (T2DM). Additionally, HSD11B1 expression was analyzed in VAT and SAT in a different cohort of 28 participants with and without obesity who underwent elective abdominal operations. RESULTS: Although polymorphisms of the two genes were not individually associated with MetS features, a synergistic effect was observed between both. Carriers of at least three minor alleles exhibited lower BMI compared to those with two or fewer minor alleles adjusting for gender and age (27.4 ± 4.9 vs. 29.3 ± 5.3 kg/m2; P = 0.005; mean ± SD). Obesity frequency was also lower in the first group (24.4% vs. 41.6%, OR = 0.43, 95% CI 0.21-0.87; P = 0.019). In the second cohort of 28 subjects, HSD11B1 gene expression in VAT was inversely correlated with BMI (r = - 0.435, P = 0.034), waist circumference (r = - 0.584, P = 0.003) and waist-to-height ratio (r = - 0.526, P = 0.010). CONCLUSIONS: These polymorphisms might interact in the protection against obesity in T2DM individuals. Obese individuals may have decreased intra-abdominal VAT HSD11B1 gene expression resulting in decreasing intra-abdominal cortisol levels as a compensatory mechanism against central and general adiposity.

7.
Diabetol Metab Syndr ; 7: 38, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26056536

RESUMO

The HSD11B1 gene is highly expressed in abdominal adipose tissue, and the enzyme it encodes catalyzes the interconversion of inactive cortisone to hormonally active cortisol. Genetic abnormalities of HSD11B1 have been associated with the development of abnormal glucose metabolism and body fat distribution. To systematically review studies evaluating the association of HSD11B1 gene expression in abdominal adipose tissue and HSD11B1 polymorphisms with obesity, the metabolic syndrome (MetS), and type 2 diabetes (T2DM), we conducted a search in MEDLINE, SCOPUS, and Cochrane Library databases in April 2015. The inclusion criteria were observational studies (cross-sectional, cohort, or case-control), conducted in adults, which analyzed the relationship of HSD11B1 polymorphisms and/or HSD11B1 expression in abdominal adipose tissue with obesity, MetS, or T2DM. Of 802 studies retrieved, 32 met the inclusion criteria (23 gene expression and 9 polymorphism studies). Twenty one studies analyzed the relationship between abdominal subcutaneous and/or visceral HSD11B1 expression with central and/or generalized obesity. Most studies reported that abdominal adipose HSD11B1 expression increased with increasing body mass index (15 studies) and abnormalities of glucose metabolism (7 studies), and varied with the presence of MetS (3 studies). Nine studies analyzed the association of 26 different HSD11B1 polymorphic variants with obesity, MetS, and T2DM. Only an Indian study found an association between a polymorphic variant at the HSD11B1 gene with MetS whereas in Pima Indians another polymorphic variant was found to be associated with T2DM. While the literature suggests that HSD11B1 is hyperexpressed in abdominal adipose tissue in subjects with obesity and abnormal glucose metabolism, this seems to be not true for HSD11B1 gene expression and MetS. Although an association of polymorphic variants of HSD11B1 with MetS in Indians and in the T2DM population of Pima Indians were found, most studies did not find a relationship between genetic polymorphic variants of HSD11B1 and obesity, MetS, and T2DM. Their reported conflicting and inconclusive results, suggesting that polymorphic variants of HSD11B1 may have only a small role in the development of metabolic abnormalities of susceptible populations in the development of MetS and T2DM.

8.
Br J Nutr ; 112(8): 1235-50, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25192422

RESUMO

Different dietary interventions have been identified as potential modifiers of adiponectin concentrations, and they may be influenced by lipid intake. We identified studies investigating the effect of dietary lipids (type/amount) on adiponectin concentrations in a systematic review with meta-analysis. A literature search was conducted until July 2013 using databases such as Medline, Embase and Scopus (MeSH terms: 'adiponectin', 'dietary lipid', 'randomized controlled trials (RCT)'). Inclusion criteria were RCT in adults analysing adiponectin concentrations with modification of dietary lipids. Among the 4930 studies retrieved, fifty-three fulfilled the inclusion criteria and were grouped as follows: (1) total dietary lipid intake; (2) dietary/supplementary n-3 PUFA; (3) conjugated linoleic acid (CLA) supplementation; (4) other dietary lipid interventions. Diets with a low fat content in comparison to diets with a high-fat content were not associated with positive changes in adiponectin concentrations (twelve studies; pooled estimate of the difference in means: -0·04 (95% CI -0·82, 0·74) µg/ml). A modest increase in adiponectin concentrations with n-3 PUFA supplementation was observed (thirteen studies; 0·27 (95% CI 0·07, 0·47) µg/ml). Publication bias was found by using Egger's test (P= 0·01) and funnel plot asymmetry. In contrast, CLA supplementation reduced the circulating concentrations of adiponectin compared with unsaturated fat supplementation (seven studies; -0·74 (95% CI -1·38, -0·10) µg/ml). However, important sources of heterogeneity were found as revealed by the meta-regression analyses of both n-3 PUFA and CLA supplementation. Results of new RCT would be necessary to confirm these findings.


Assuntos
Adiponectina/sangue , Gorduras na Dieta/administração & dosagem , Regulação para Cima , Adiponectina/agonistas , Adulto , Dieta com Restrição de Gorduras , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/uso terapêutico , Suplementos Nutricionais/efeitos adversos , Regulação para Baixo , Ácidos Graxos Ômega-3/uso terapêutico , Humanos , Ácidos Linoleicos Conjugados/efeitos adversos , Ácidos Linoleicos Conjugados/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes
9.
Zootaxa ; 3779: 93-100, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24871716

RESUMO

This paper describes the tadpole and advertisement call of Phyllodytes acuminatus, based on specimens from the Parque Nacional do Catimbau, in the municipality of Buíque, State of Pernambuco, Northeastern Brazil. The overall morphology of P. acuminatus tadpole is similar to that of most species of the genus. The presence of a double row of marginal papillae surrounding all the oral apparatus (except on most of the upper labium which has a dorsal gap) was a characteristic that differentiate P. acuminatus from the other species of the genus. Furthermore, the call structure of the species (unpulsed notes with harmonic structure) fits it in the group composed of P. kautskyi and P. melanomystax.


Assuntos
Anuros/classificação , Anuros/fisiologia , Larva/crescimento & desenvolvimento , Vocalização Animal , Animais , Anuros/anatomia & histologia , Anuros/crescimento & desenvolvimento , Tamanho Corporal , Brasil , Feminino , Larva/anatomia & histologia , Larva/classificação , Masculino
10.
Diabetol Metab Syndr ; 6(1): 26, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24568287

RESUMO

BACKGROUND: Adiponectin is a major regulator of glucose and lipid homeostasis by its insulin sensitizer properties. Since decreased insulin sensitivity is linked to metabolic syndrome (MS), decreased adiponectin levels may be related to its development. The purpose of the study was to investigate the relationship between adiponectin levels and MS. METHODS: Firstly, we cross-sectionally examined subjects with or without MS submitted to an oral glucose tolerance test at Hospital de Clínicas de Porto Alegre (n = 172). A replication analysis was performed in subjects (n = 422) undergoing cardiac angiography at Hospital São Paulo. Subchronic inflammation (US-CRP), coagulation marker (fibrinogen), insulin sensitivity and resistance (Matsuda ISI and HOMA-IR) were estimated. Plasma total and high molecular weight (HMW) adiponectin were measured. RESULTS: Total and HMW adiponectin levels were lower in MS subjects (P < 0.05). Total adiponectin levels were lower in the presence of high waist circumference, low HDL-cholesterol and elevated triglyceride criteria in both samples and by elevated blood pressure and glucose criteria in Porto Alegre. HMW adiponectin levels were lower in the presence of low HDL-cholesterol, elevated triglycerides, and glucose criteria. Total adiponectin levels were positively related with HDL-cholesterol and ISI Matsuda, negatively related with waist circumference, glucose, triglycerides, HOMA-IR, and US-CRP and not related with blood pressure. While adjusting for sex and age, increased adiponectin levels remained associated with a reduced prevalence ratio for MS in both cohorts (P = 0.001). CONCLUSIONS: Adiponectin levels decreased with increasing number of MS criteria, and it is in part determined by its relationship with HDL, triglycerides and abdominal adiposity.

11.
Int J Oncol ; 28(2): 457-62, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16391801

RESUMO

A current target of cancer gene therapy is tumour vasculature. We present a gene-directed enzyme prodrug therapy (GDEPT) approach to target tumours in vivo by modifying endothelial cells (ECs) with the Escherichia coli nitroreductase (ntr) gene. Firstly, we isolated two ntr-transfected clones of the human umbilical vein endothelial cell line (HUV-EC-C/ntr+) that showed a differential sensitivity in vitro to the prodrug, dinitroaziridinylbenzamide (CB1954), with respect to untransfected HUV-EC-C cells (HUV-EC-C/ntr-). Then, these cells were injected subcutaneously into nude mice, either in association with the murine melanoma cell line, B16-F10 ('co-injected' groups), or into tumour-bearing animals ('post-injected' groups). After intratumoural injection, we demonstrated, using PCR analysis, that human ECs resided in the site of the injection without spreading to other organs, such as the liver or lung. After the treatment of mice with CB1954, we observed a prolonged survival of animals carrying the HUV-EC-C/ntr+ clones with respect to control animals injected with HUV-EC-C/ntr- cells. Significant differences in tumour growth were also observed and, after immuno-histological analysis, tumours carrying HUV-EC-C/ntr+ clones showed large areas of tumour necrosis, probably due to tumour ischemia, as well as the presence of major histocompatibility complex class-II (MHC-II) positive cells. Collectively, our data indicate that targeting of the tumour vasculature by this GDEPT strategy may be an efficient approach for cancer treatment in vivo, depending on two possible bystander mechanisms based on tumour ischemia and immune cell activation.


Assuntos
Sistemas de Liberação de Medicamentos , Células Endoteliais/metabolismo , Melanoma Experimental/irrigação sanguínea , Nitrorredutases/genética , Animais , Antineoplásicos/farmacologia , Aziridinas/farmacologia , Efeito Espectador , Sobrevivência Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Escherichia coli/genética , Terapia Genética , Humanos , Melanoma Experimental/prevenção & controle , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/prevenção & controle , Nitrorredutases/metabolismo , Pró-Fármacos/farmacologia , Transfecção
12.
Biochem Biophys Res Commun ; 311(4): 822-8, 2003 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-14623255

RESUMO

Tumor cells are elusive targets for standard anticancer chemotherapy due to their heterogeneity and genetic instability. On the other hand, proliferating host endothelial cells (ECs) are genetically stable and have a low mutational rate. Thus, antiangiogenic therapy directed against tumor's ECs should, in principle, improve the efficacy of antitumor therapy by inducing little or no drug resistance. Here we present a gene-directed enzyme prodrug therapy (GDEPT) strategy for targeting the tumor vasculature, using the Escherichia coli nitroreductase (ntr) gene delivery associated with the treatment with the prodrug CB1954. In a first time we demonstrated the ability of the ntr/CB1954 system to induce an apoptotic-mediated cell death on monolayer cultures of human umbilical vein ECs (HUV-EC-C). Then, when ntr-transfected HUV-EC-C cells (HUV-EC-C/ntr(+)) were associated in a three-dimensional (3-D) multicellular nodule model with untransfected B16-F10 murine melanoma cell line, we observed a CB1954-mediated bystander cell killing effect from endothelial to neighboring melanoma cells. To our knowledge, this is the first report indicating that GDEPT-based antiangiogenic targeting may be an effective approach for cancer treatment relied on the spreading of the bystander effect from endothelial to tumor cells.


Assuntos
Aziridinas , Efeito Espectador , Endotélio Vascular , Terapia Genética , Melanoma , Nitrorredutases , Animais , Humanos , Camundongos , Células 3T3 , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Aziridinas/administração & dosagem , Efeito Espectador/genética , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Técnicas de Cocultura/métodos , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Terapia Genética/métodos , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Nitrorredutases/genética , Nitrorredutases/metabolismo , Pró-Fármacos/administração & dosagem , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
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