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1.
Am J Physiol Regul Integr Comp Physiol ; 316(4): R376-R386, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30789791

RESUMO

The objectives of this study were to assess the relationship between inflammation and obstructive sleep apnea (OSA) and determine whether the lifestyle program's effects on inflammatory markers are associated with changes in anthropometric parameters, cardiorespiratory fitness, sleep duration, and OSA severity in severely obese adolescents. Participants were aged 14.6 (SD 1.2) yr, with a body mass index (BMI) of 40.2 (SD 6.5) kg/m2. Sleep, anthropometric parameters, glucose metabolism, inflammatory profile, and cardiorespiratory fitness [V̇o2peak relative to body weight (V̇o2peakBW) and fat-free mass (V̇o2peakFFM)] were assessed at admission and at the end of a 9-mo lifestyle intervention program (LIP). Associations between C-reactive protein (CRP) concentrations and BMI, sex, oxygen desaturation index (ODI), sleep fragmentation, total sleep time (TST), and V̇o2peak were assessed via ANCOVA. Twenty-three subjects completed the study. OSA subjects ( n = 13) exhibited higher CRP concentrations and a trend for higher BMI than non-OSA subjects ( P = 0.09) at admission. After intervention, OSA was normalized in six subjects, and CRP significantly decreased in the OSA group and in the whole population. In both groups, leptin levels significantly decreased, whereas adiponectin concentrations increased. At admission, BMI adjusted for sex, arousal index, ODI, TST, and V̇o2peakBW was associated with CRP levels (adjusted r2 = 0.32, P < 0.05). The decrease in CRP concentrations postintervention was associated with enhanced V̇o2peakFFM adjusted for sex, weight loss, and changed sleep parameters (adjusted r2 = 0.75, P < 0.05). Despite higher amounts of CRP in OSA subjects, obesity severity outweighs the proinflammatory effects of OSA, short sleep duration, and low cardiorespiratory fitness. However, enhanced cardiorespiratory fitness is associated with the decrease of inflammation after controlling for the same parameters.


Assuntos
Proteína C-Reativa/metabolismo , Aptidão Cardiorrespiratória , Estilo de Vida , Obesidade Infantil/metabolismo , Obesidade Infantil/terapia , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/terapia , Tonsila Faríngea/anatomia & histologia , Tonsila Faríngea/crescimento & desenvolvimento , Adolescente , Limiar Anaeróbio , Composição Corporal , Índice de Massa Corporal , Proteína C-Reativa/análise , Teste de Esforço , Feminino , Glucose/metabolismo , Humanos , Masculino , Obesidade Infantil/complicações , Privação do Sono/etiologia , Privação do Sono/metabolismo , Privação do Sono/terapia , Transtornos do Sono-Vigília/etiologia
2.
J Clin Sleep Med ; 14(6): 967-976, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29852904

RESUMO

STUDY OBJECTIVES: Physical exercise and lifestyle modification are recognized as adjunct therapy for obstructive sleep apnea (OSA) in overweight adults. The objectives of this study were to investigate the effects of long-term physical exercise combined with a balanced diet on sleep architecture, sleep duration, and OSA in adolescents with severe obesity. METHODS: This interventional study was conducted in a nursing institution. Participants were aged 14.6 ± 1.2 years with obesity (body mass index (BMI) = 40.2 ± 6.5 kg/m2). At admission and at 9 months, participants underwent ambulatory polysomnography and incremental maximal exercise testing to determine cardiorespiratory fitness. RESULTS: Twenty-four subjects completed the study. Analyses were performed on the whole population and on a subgroup of subjects with OSA (OSA-subgroup). OSA, defined as obstructive apnea-hypopnea index (OAHI) ≥ 2 events/h, was diagnosed in 58.3% of the population. OAHI was only associated with fat mass in males (r = .75, P < .05). At 9 months postintervention, weight loss (-11.1 kg, P < .0001) and improved cardiorespiratory fitness (VO2peak: +4.9 mL/min/kg, P < .001) were found in the whole population. Sleep duration was increased (+34 minutes, P < .05) and sleep architecture was changed with an increase of rapid eye movement sleep (+2.5%, P < .05) and a decrease of stage N3 sleep (-3.1%, P < .001). Similar results were found in the OSA subgroup. However, OAHI remained unchanged (P = .18). CONCLUSIONS: A combination of supervised aerobic exercise and a balanced diet led to weight loss, improved aerobic capacity, and modified sleep architecture without changes in OSA. COMMENTARY: A commentary on this article appears in this issue on page 907. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov, Title: Exercise and Venous Compression on Upper Airway Resistance in Obese Teenagers With OSA (OBESOMAC), URL: https://clinicaltrials.gov/ct2/show/NCT02588469, Identifier: NCT02588469.


Assuntos
Dieta/métodos , Exercício Físico , Obesidade Mórbida/complicações , Obesidade Mórbida/terapia , Obesidade Infantil/complicações , Obesidade Infantil/terapia , Apneia Obstrutiva do Sono/complicações , Adolescente , Feminino , Humanos , Estilo de Vida , Masculino , Polissonografia , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento
3.
Mol Biosyst ; 12(12): 3530-3543, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27787525

RESUMO

The term "venomics" was coined to describe the global study of venom and venom glands, targeting comprehensive characterization of the whole toxin profile of a venomous animal by means of proteomics, transcriptomics, genomics and bioinformatics studies. This integrative approach is supported by the rapid evolution of protein, RNA and DNA sequencing techniques, as well as databases, knowledge-bases and biocomputing algorithms. The aim of this review is to illustrate advances in the field of venomics during the last decade, addressing each step of the procedure, from sample collection to data treatment. A special focus is made on new perspectives for a better understanding of the venomous function and for fostering the discovery of new venom-derived drug candidates.


Assuntos
Genômica , Proteômica , Peçonhas/genética , Peçonhas/metabolismo , Animais , Biologia Computacional/métodos , Genoma , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Proteômica/métodos , Manejo de Espécimes , Transcriptoma , Peçonhas/isolamento & purificação , Peçonhas/uso terapêutico
4.
Mol Phylogenet Evol ; 80: 186-92, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25132129

RESUMO

Cone snails have long been studied both by taxonomists for the diversity of their shells and by biochemists for the potential therapeutic applications of their toxins. Phylogenetic approaches have revealed that different lineages of Conus evolved divergent venoms, a property that is exploited to enhance the discovery of new conotoxins, but is rarely used in taxonomy. Specimens belonging to the Indo-West Pacific Conus lividus species complex were analyzed using phenetic and phylogenetic methods based on shell morphology, COI and 28S rRNA gene sequences and venom mRNA expression and protein composition. All methods converged to reveal a new species, C. conco n. sp. (described in Supplementary data), restricted to the Marquesas Islands, where it diverged recently (∼3mya) from C. lividus. The geographical distribution of C. conco and C. lividus and their phylogenetic relationships suggest that the two species diverged in allopatry. Furthermore, the diversity of the transcript sequences and toxin molecular masses suggest that C. conco evolved unique toxins, presumably in response to new selective pressure, such as the availability of new preys and ecological niches. Furthermore, this new species evolved new transcripts giving rise to original toxin structures, probably each carrying specific biological activity.


Assuntos
Evolução Biológica , Conotoxinas/química , Caramujo Conus/classificação , Filogenia , Exoesqueleto/anatomia & histologia , Animais , Teorema de Bayes , Caramujo Conus/genética , Ilhas do Pacífico , Mapeamento de Peptídeos , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Transcriptoma
5.
Toxicon ; 51(7): 1288-302, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18471845

RESUMO

Snake venoms are known to be an extensive source of bioactive peptides. Bradykinin-potentiating peptides (BPPs) are inhibitors of the angiotensin-converting enzyme that have already been identified in the venom of many snake, scorpion, spider and batrachian species. Their most characteristic structural features are an invariable N-terminal pyroglutamate residue (pGlu or Z) and two consecutive proline residues at the C-terminus. Fragmentation of BPPs by collision-induced dissociation during electrospray tandem mass spectrometry analysis (ESI-MS/MS) generates a predominant signal at m/z 213.1 corresponding to the y-ion of the terminal Pro-Pro fragment. In addition, signals at m/z 226.1 and 240.1 that correspond to the b ions of the N-terminus pGlu-Asn and pGlu-Lys, respectively, can often be observed. Based on these structural determinants, the present work describes an original methodology for the discovery of BPPs in natural extracts using liquid chromatography coupled to ESI-MS/MS operated in precursor ion-scan mode. The venom of the Bothrops moojeni snake was used as a model and the methodology was applied for subsequent structural analysis of the identified precursors by tandem mass spectrometry on quadrupole-time-of-flight (Q-TOF) and matrix-assisted laser-desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-MS/MS) instruments. More than 40 peptides below 2500 Da could be detected, among them 20 were shown to belong to the BPP-like family including the related tripeptides pGlu-Lys-Trp and pGlu-Asn-Trp. A total of 15 new sequences have been identified using this approach.


Assuntos
Bothrops/metabolismo , Bradicinina/química , Venenos de Crotalídeos/química , Espectrometria de Massas/métodos , Peptídeos/química , Animais , Fragmentos de Peptídeos/química , Mapeamento de Peptídeos , Ácido Pirrolidonocarboxílico/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem
6.
Artigo em Inglês | MEDLINE | ID: mdl-16824809

RESUMO

Mutations in the ubiquitous factor eIF2B involved in protein synthesis and its regulation have been reported in human brain genetic disorders. In order to analyse the functional consequences of the mutations and to find specific biomarkers of eIF2B-related disorders, proteomics and peptidomics studies were performed on lymphoblasts from eIF2B-mutated patients versus healthy patients. Curiously, following two-dimensional gel electrophoresis and mass fingerprints, mutations in the eIF2B complex did not significantly affect the proteome of the mutated lymphoblasts extracts. However, liquid chromatography based peptidomics studies revealed one apparently instable candidate compound in five out of the six mutated lymphoblastoid cell lines investigated.


Assuntos
Fator de Iniciação 2B em Eucariotos/metabolismo , Linfócitos/metabolismo , Mutação , Peptídeos/metabolismo , Proteômica , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel Bidimensional , Feminino , Humanos , Masculino , Espectrometria de Massas por Ionização por Electrospray
7.
Toxicon ; 47(6): 676-87, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16626777

RESUMO

Due to their complexity and diversity, animal venoms represent an extensive source of bioactive compounds such as peptides and proteins. Conventional approaches for their characterization often require large quantities of biological material. Current mass spectrometry (MS) techniques now give access to a wealth of information in a short working time frame with minute amounts of sample. Such MS approaches may now be used for the discovery of novel compounds, and once their structure has been determined they may be synthesized and tested for functional activity. Molecular mass fingerprints of venoms allow the rapid identification of known toxins as well as preliminary structural characterization of new compounds. De novo peptide sequencing by tandem mass spectrometry (MS/MS) offers rapid access to partial or total primary peptide structures. This article, written as a tutorial, also contains new material: molecular mass fingerprint analysis of Orthochirus innesi scorpion venom, and identification of components from bumblebee Bombus lapidarius venom, both collected from one single specimen. The structure of the three major peptides detected in the Bombus venom was fully characterized in one working day by de novo sequencing using an electrospray ionization hybrid quadrupole time-of-flight instrument (ESI-QqTOF) and a matrix-assisted laser desorption ionization time-of-flight instrument (MALDI-LIFT-TOF-TOF). After presenting the MS-based sequence elucidation, perspectives in using MS and MS/MS techniques in toxinology are discussed.


Assuntos
Venenos de Abelha/análise , Espectrometria de Massas/métodos , Mapeamento de Peptídeos/métodos , Venenos de Escorpião/análise , Animais , Abelhas , Dados de Sequência Molecular , Proteômica , Escorpiões/química
8.
Proteomics ; 4(8): 2333-51, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15274127

RESUMO

We present an integrated proteomics platform designed for performing differential analyses. Since reproducible results are essential for comparative studies, we explain how we improved reproducibility at every step of our laboratory processes, e.g. by taking advantage of the powerful laboratory information management system we developed. The differential capacity of our platform is validated by detecting known markers in a real sample and by a spiking experiment. We introduce an innovative two-dimensional (2-D) plot for displaying identification results combined with chromatographic data. This 2-D plot is very convenient for detecting differential proteins. We also adapt standard multivariate statistical techniques to show that peptide identification scores can be used for reliable and sensitive differential studies. The interest of the protein separation approach we generally apply is justified by numerous statistics, complemented by a comparison with a simple shotgun analysis performed on a small volume sample. By introducing an automatic integration step after mass spectrometry data identification, we are able to search numerous databases systematically, including the human genome and expressed sequence tags. Finally, we explain how rigorous data processing can be combined with the work of human experts to set high quality standards, and hence obtain reliable (false positive < 0.35%) and nonredundant protein identifications.


Assuntos
Líquidos Corporais/química , Perfilação da Expressão Gênica , Gestão da Informação/métodos , Proteínas/análise , Proteínas/química , Proteômica/métodos , Cromatografia/instrumentação , Cromatografia/métodos , Biologia Computacional , Bases de Dados Factuais , Humanos , Gestão da Informação/instrumentação , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Peptídeos/análise , Proteínas/genética , Proteínas/metabolismo , Reprodutibilidade dos Testes , Interface Usuário-Computador
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