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1.
Nature ; 539(7628): 289-293, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27652894

RESUMO

The basal ganglia, a group of subcortical nuclei, play a crucial role in decision-making by selecting actions and evaluating their outcomes. While much is known about the function of the basal ganglia circuitry in selection, how these nuclei contribute to outcome evaluation is less clear. Here we show that neurons in the habenula-projecting globus pallidus (GPh) in mice are essential for evaluating action outcomes and are regulated by a specific set of inputs from the basal ganglia. We find in a classical conditioning task that individual mouse GPh neurons bidirectionally encode whether an outcome is better or worse than expected. Mimicking these evaluation signals with optogenetic inhibition or excitation is sufficient to reinforce or discourage actions in a decision-making task. Moreover, cell-type-specific synaptic manipulations reveal that the inhibitory and excitatory inputs to the GPh are necessary for mice to appropriately evaluate positive and negative feedback, respectively. Finally, using rabies-virus-assisted monosynaptic tracing, we show that the GPh is embedded in a basal ganglia circuit wherein it receives inhibitory input from both striosomal and matrix compartments of the striatum, and excitatory input from the 'limbic' regions of the subthalamic nucleus. Our results provide evidence that information about the selection and evaluation of actions is channelled through distinct sets of basal ganglia circuits, with the GPh representing a key locus in which information of opposing valence is integrated to determine whether action outcomes are better or worse than expected.


Assuntos
Gânglios da Base/citologia , Gânglios da Base/fisiologia , Tomada de Decisões , Vias Neurais/fisiologia , Punição , Recompensa , Animais , Condicionamento Clássico , Retroalimentação Fisiológica , Feminino , Globo Pálido/citologia , Globo Pálido/fisiologia , Ácido Glutâmico/metabolismo , Habenula/citologia , Habenula/fisiologia , Masculino , Camundongos , Neurônios/metabolismo , Optogenética , Vírus da Raiva/fisiologia , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo
2.
J Neurosci ; 33(46): 18015-21, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24227713

RESUMO

Tuberous sclerosis complex (TSC) is a leading genetic cause of autism. The TSC proteins Tsc1 and Tsc2 control the mTORC1 signaling pathway in diverse cells, but how the mTORC1 pathway is specifically regulated in neurons remains to be elucidated. Here, using an interaction proteomics approach in neural cells including neurons, we uncover the brain-enriched protein huntingtin-associated protein 1 (Hap1) as a novel functional partner of Tsc1. Knockdown of Hap1 promotes specification of supernumerary axons in primary hippocampal neurons and profoundly impairs the positioning of pyramidal neurons in the mouse hippocampus in vivo. The Hap1 knockdown-induced phenotypes in primary neurons and in vivo recapitulate the phenotypes induced by Tsc1 knockdown. We also find that Hap1 knockdown in hippocampal neurons induces the downregulation of Tsc1 and stimulates the activity of mTORC1, as reflected by phosphorylation of the ribosomal protein S6. Inhibition of mTORC1 activity suppresses the Hap1 knockdown-induced polarity phenotype in hippocampal neurons. Collectively, these findings define a novel link between Hap1 and Tsc1 that regulates neuronal mTORC1 signaling and neuronal morphogenesis, with implications for our understanding of developmental disorders of cognition.


Assuntos
Encéfalo/crescimento & desenvolvimento , Morfogênese/fisiologia , Complexos Multiproteicos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Células Cultivadas , Feminino , Células HEK293 , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Ligação Proteica/fisiologia , Ratos , Transdução de Sinais/fisiologia , Proteína 1 do Complexo Esclerose Tuberosa
3.
PLoS Genet ; 4(7): e1000111, 2008 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-18604272

RESUMO

While genetic screens have identified many genes essential for neurite outgrowth, they have been limited in their ability to identify neural genes that also have earlier critical roles in the gastrula, or neural genes for which maternally contributed RNA compensates for gene mutations in the zygote. To address this, we developed methods to screen the Drosophila genome using RNA-interference (RNAi) on primary neural cells and present the results of the first full-genome RNAi screen in neurons. We used live-cell imaging and quantitative image analysis to characterize the morphological phenotypes of fluorescently labelled primary neurons and glia in response to RNAi-mediated gene knockdown. From the full genome screen, we focused our analysis on 104 evolutionarily conserved genes that when downregulated by RNAi, have morphological defects such as reduced axon extension, excessive branching, loss of fasciculation, and blebbing. To assist in the phenotypic analysis of the large data sets, we generated image analysis algorithms that could assess the statistical significance of the mutant phenotypes. The algorithms were essential for the analysis of the thousands of images generated by the screening process and will become a valuable tool for future genome-wide screens in primary neurons. Our analysis revealed unexpected, essential roles in neurite outgrowth for genes representing a wide range of functional categories including signalling molecules, enzymes, channels, receptors, and cytoskeletal proteins. We also found that genes known to be involved in protein and vesicle trafficking showed similar RNAi phenotypes. We confirmed phenotypes of the protein trafficking genes Sec61alpha and Ran GTPase using Drosophila embryo and mouse embryonic cerebral cortical neurons, respectively. Collectively, our results showed that RNAi phenotypes in primary neural culture can parallel in vivo phenotypes, and the screening technique can be used to identify many new genes that have important functions in the nervous system.


Assuntos
Genoma , Neurônios/metabolismo , Interferência de RNA , Animais , Células Cultivadas , Drosophila/genética , Genômica , Camundongos , Sistema Nervoso/metabolismo , Fenótipo , RNA Interferente Pequeno , Proteína ran de Ligação ao GTP/metabolismo
4.
Adv Nutr ; 12(4): 1424-1437, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33439976

RESUMO

HIV infection and undernutrition remain significant public health concerns for infants and children. In infants and children under these conditions, undernutrition is one of the leading causes of death. Proper management of nutrition and related nutrition complications in these groups with increased nutrition needs are prominent challenges, particularly in HIV-prevalent poor-resource environments. Several studies support the complexity of the relation between HIV infection, nutrition, and the immune system. These elements interact and create a vicious circle of poor health outcomes. Recent studies on the use of probiotics as a novel approach to manage microbiome imbalance and gut-mucosal impairment in HIV infection are gaining attention. This new strategy could help to manage dysbiosis and gut-mucosal impairment by reducing immune activation, thereby potentially forestalling unwanted health outcomes in children with HIV. However, existing trials on HIV-infected children are still insufficient. There are also conflicting reports on the dosage and effectiveness of single or multiple micronutrient supplementation in the survival of HIV-infected children with severe acute malnutrition. The WHO has published guidelines that include time of initiation of antiretroviral therapy for HIV-pregnant mothers and their HIV-exposed or HIV-infected children, micronutrient supplementation, dietary formulations, prevention, and management of HIV therapy. However, such guidelines need to be reviewed owing to recent advances in the field of nutrition. There is a need for new intervention studies, practical strategies, and evidence-based guidelines to reduce the disease burden, improve adherence to treatment regimen, and enhance the nutrition, health, and well-being of HIV-infected infants and children. This review provides up-to-date scientific information on current knowledge and existing challenges for nutrition therapy in HIV-infected infants and children. Moreover, it presents new research findings that could be incorporated into current guidelines.


Assuntos
Infecções por HIV , Desnutrição , Terapia Nutricional , Criança , Feminino , Infecções por HIV/complicações , Humanos , Lactente , Mães , Estado Nutricional , Gravidez
5.
Microbiol Resour Announc ; 10(20)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34016672

RESUMO

Infectious hypodermal and hematopoietic necrosis virus (IHHNV) is a shrimp virus listed by the World Organisation for Animal Health (OIE). In this study, we report the genomic sequences of 12 IHHNV strains obtained from shrimp samples from aquaculture cultures from the Tumbes region of Peru.

6.
Food Nutr Bull ; 31(1): 118-29, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20461909

RESUMO

Vitamin A deficiency in Central America was first identified as a public health problem in the 1950s. It affected primarily children. The main underlying cause was a deficient intake of pre-formed vitamin A, but infection and intestinal parasitism also played important roles. INCAP focused its efforts on overcoming this problem and developed, as a short-term solution, the technology to fortify sugar with vitamin A. Fortification programs were implemented in several Central American countries. Evaluation of these programs revealed a significant impact-not only on vitamin A status, but also on iron nutrition and hematological condition. Longer-term solutions, like increasing the availability and consumption of vitamin A-rich foods, were later suggested and operational tools were developed to assist the countries in the region in the implementation, evaluation and monitoring of their own fortification programs.


Assuntos
Academias e Institutos/história , Deficiência de Vitamina A/história , Vitamina A/administração & dosagem , Anemia Ferropriva/complicações , Anemia Ferropriva/prevenção & controle , Carotenoides/administração & dosagem , Carotenoides/análise , América Central/epidemiologia , Dieta , Sacarose Alimentar , Diterpenos , Análise de Alimentos , Abastecimento de Alimentos , Alimentos Fortificados/história , História do Século XX , Humanos , Política Nutricional/história , Política Nutricional/tendências , Ésteres de Retinil , Vitamina A/análogos & derivados , Vitamina A/análise , Vitamina A/farmacologia , Vitamina A/uso terapêutico , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/prevenção & controle
7.
Nutrients ; 12(2)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973015

RESUMO

Iron fortification of staple foods is a common practice around the world to reduce the prevalence of iron-deficiency anemia. More recently, fortified condiments, including salts, sauces, and powders, have been tested in various efficacy trials. However, there is limited information on how nutritional, environmental, and experimental factors affect their efficacy and effectiveness. The purpose of the present work was to systematically review performance factors affecting the efficacy of condiment fortification trials. Three databases were searched using a standardized keyword search and included based on four-point inclusion criteria. Studies were evaluated against a quality assessment tool and effect sizes were calculated. Studies were ranked as low or high performing, based on whether or not they significantly improved iron-deficiency outcomes (hemoglobin, anemia prevalence, and ferritin levels). Of the 955 retrieved studies, 23 were included-of which, nine performed poorly, eight performed highly, and six were classified as neither because they did not meet the criteria of assessing the three iron outcomes. Results showed that unsuccessful trials did not consider environmental factors such as parasitic infections, nutritional factors such as micronutrient deficiencies other than iron, consumer acceptability of the product or experimental factors such as monitoring and adherence to the trials. Two common performing factors identified among those studies performing highly vs. those that did not were the control of sensory changes and monitoring of consumption compliance (i.e., dose delivery). The present work can be used as decision-making support for nutrition policy makers when determining the appropriate implementation of condiment fortification programs.


Assuntos
Anemia Ferropriva/prevenção & controle , Condimentos/análise , Alimentos Fortificados , Ferro/administração & dosagem , Adolescente , Adulto , Idoso , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Ferro/sangue , Deficiências de Ferro , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Gravidez , Prevalência , Adulto Jovem
8.
J Ophthalmic Vis Res ; 15(4): 565-570, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133448

RESUMO

PURPOSE: To describe the clinical and histopathological findings of a case of intraocular metastasis due to colorectal adenocarcinoma and to carry out a literature review. CASE REPORT: A 64-year-old man with a history of tumor resection due to infiltrating colorectal adenocarcinoma three years previously sought ophthalmological care because of severe ocular pain without response to medical treatment and progressive vision loss in the left eye. On ultrasonographic examination, there was a heterogeneous intraocular choroidal tumor, which occupied approximately 40% of the vitreous cavity, as well as peritumoral serous retinal detachment. The patient underwent left eyeball enucleation. The histopathological diagnosis was metastatic tubular adenocarcinoma involving the retina and choroid that partially infiltrated the sclera and the proximal optic nerve. CONCLUSION: The present case highlights a rare pathological entity associated with variable therapeutic schemes and survival times and poor prognosis in patients with metastatic intraocular tumors due to colorectal adenocarcinoma.

9.
Biochemistry ; 48(42): 10066-77, 2009 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-19754159

RESUMO

Chlorpromazine (CPZ), a potent nicotinic acetylcholine receptor (nAChR) noncompetitive antagonist, binds with higher affinity in the ion channel in the desensitized state than in the closed channel state and with low affinity to additional sites in nAChR-rich membranes. For nAChR equilibrated with agonist, we confirm previous reports that [(3)H]CPZ occupies a site near the cytoplasmic end of the M2 ion channel domain, photolabeling positions M2-2, M2-6, and/or M2-9 in each subunit. We find that [(3)H]CPZ also binds at the extracellular end of the channel, photolabeling amino acids at positions M2-16 (alpha,gamma), M2-17 (alpha,beta,delta), and M2-20 (alpha,beta,delta). The photolabeling at the cytoplasmic end of the channel is fully inhibitable by phencyclidine or proadifen, whereas neither drug inhibits [(3)H]CPZ photolabeling at the extracellular end, establishing that positively charged drugs can bind simultaneously at the cytoplasmic and extracellular ends of the ion channel. [(3)H]CPZ photolabeling is not detected in the transmembrane domain outside the ion channel, but it photolabels alphaMet-386 and alphaSer-393 in the cytoplasmic alphaMA helix. In the nAChR equilibrated with alpha-bungarotoxin to stabilize the nAChR in a closed state, [(3)H]CPZ photolabels amino acids at M2-5 (alpha), M2-6 (alpha,beta,delta), and M2-9 (beta,delta), with no labeling at M2-2. These results provide novel information about the modes of drug binding within the nAChR ion channel and indicate that within the nAChR transmembrane domain, the binding of cationic aromatic amine antagonists can be restricted to the ion channel domain, in contrast to the uncharged, allosteric potentiators and inhibitors that also bind within the delta subunit helix bundle and at subunit interfaces.


Assuntos
Clorpromazina/química , Antagonistas Nicotínicos/química , Receptores Nicotínicos/química , Receptores Nicotínicos/metabolismo , Torpedo/metabolismo , Animais , Sítios de Ligação , Clorpromazina/metabolismo , Antagonistas Nicotínicos/metabolismo , Marcadores de Fotoafinidade
10.
Regul Toxicol Pharmacol ; 55(3): 394-402, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19766157

RESUMO

The objective was to study the safety of a Napin-Rich Canola Protein Isolate (NRCPI) fed to rats at various levels for 13-weeks. The study included four groups (20 animals/sex/group) of young Sprague Dawley rats. They were fed ad libitum with an AIN-93G based protein-free diet containing, respectively, 5%, 10% and 20% (w/w) NRCPI (test article) or 20% (w/w) vitamin-free casein (control article). Protein levels were adjusted at 18% in all groups with vitamin-free casein. Body weights, food consumption, locomotor activity and behavioral and clinical pathology parameters were recorded at various points in the study, followed by macroscopic examination, determination of organ weights and microscopic examination at termination. There were no test article-related effects on ophthalmology, functional observations, hematology, serum chemistry, urinalysis, organ weights and macroscopic or microscopic findings. Lower body weight gains were observed in the 10% NRCPI-treated males and the 20% NRCPI-treated males and females. The lower body weight gains were associated with significantly lower food consumption. Therefore, for NRCPI the No Observed Adversed Effect Level (NOAEL) was considered to be 20% (the highest fed level); equivalent to 12.46 g/kg BW/day for males and 14.95 g/kg BW/day for females. The NRCPI was considered safe under the tested conditions.


Assuntos
Albuminas 2S de Plantas/toxicidade , Peso Corporal/efeitos dos fármacos , Brassica napus/química , Animais , Comportamento Animal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
12.
Nat Neurosci ; 27(7): 1214, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982198
13.
Nat Neurosci ; 27(4): 606, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38589548
14.
Ann N Y Acad Sci ; 1446(1): 66-80, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30346034

RESUMO

Countries around the world have been implementing public health interventions to provide vitamins and minerals. There is a concern that the cumulative micronutrient contribution of coexisting programs, when targeting the same population, may exceed their safe levels of intake, thus potentially challenging the primum non nocere principle. We assessed the regulatory framework of such interventions and determined qualitatively whether there were provisions in the regulations that called for coordination among programs to ensure their innocuousness. Country cases from various WHO regions were selected for the study: (1) the Americas: Chile, Costa Rica, and Guatemala; (2) Africa: Malawi, Uganda, and Zambia; (3) South Asia: Bangladesh; and (4) the Western Pacific Region: China and the Philippines. We did not identify any provisions in the existing regulations requiring coordination mechanisms among interventions. However, in some countries, governments have established national micronutrient fortification commissions or alliances aimed to foster interprogram coordination. Their focus, however, has been mostly on the efficacy of the programs and less on their safety. A regulatory framework for coexisting micronutrient interventions should be comprehensive, accounting for all micronutrient sources and including regulatory provisions for coordination among programs.


Assuntos
Micronutrientes/administração & dosagem , Política Nutricional , Saúde Pública , Países Desenvolvidos , Países em Desenvolvimento , Humanos
15.
Shock ; 52(5): e68-e75, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30601330

RESUMO

Sepsis is a life-threatening condition associated with failure of at least one organ in the presence of infection. Along with SIRS, the acute systemic inflammatory syndrome without documented infection, sepsis represents a main health problem in intensive care units around the world. Hypercytokinemia and overexpression of activation-markers on leukocytes are frequently reported in SIRS/sepsis. Leukocyte functions including antibody mediated-phagocytosis, pathogen recognition, and migration appear to be disabled in SIRS/septic patients. Our aim was to evaluate the so-called activation immunophenotype and functions related to infection contention in phagocytes from patients with sepsis. We analyzed blood samples from 44 patients with SIRS/sepsis and 14 healthy volunteers. CD16, CD69, CD64, CCR7, and TREM-1 levels were determined on the surface of neutrophils and monocytes. Phagosome maturation and p38, STAT3, and STAT5 phosphorylation were evaluated in these phagocytes. As expected, sepsis and SIRS patients had increased serological levels of pro- and anti-inflammatory cytokines. E coli internalization was not increased in monocytes from patients with SIRS/sepsis, despite increased numbers of circulating neutrophils and monocytes (P < 0.05) and overexpression of CD64 and CD69 in neutrophils (P < 0.05), TREM-1 (P < 0.01), CD69 (P < 0.001), and CCR7 (P < 0.05). Moreover, phagosome maturation was decreased in phagocytes from patients with SIRS/sepsis syndrome (P < 0.00001). Furthermore, p38 and STAT-3 phosphorylation elicited by LPS or IL-10 (respectively) was diminished in neutrophils and monocytes from patients (P < 0.05). Our results indicate that "activation markers" may not reflect higher functionality, so a more profound analysis should be made before assuming that the activated immunophenotype means increased phagocyte responses.


Assuntos
Antígenos CD/imunologia , Neutrófilos/imunologia , Receptores CCR7/imunologia , Sepse/imunologia , Receptor Gatilho 1 Expresso em Células Mieloides/imunologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Sepse/patologia
16.
Nat Neurosci ; 26(8): 1319, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37537348
17.
Nat Neurosci ; 26(5): 725, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37156875
18.
Nat Neurosci ; 25(9): 1121, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36042308
19.
Nat Neurosci ; 25(7): 838, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35790860
20.
Nat Neurosci ; 25(4): 404, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35383333
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