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1.
Eur J Appl Physiol ; 122(1): 185-197, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34633508

RESUMO

PURPOSE: Sickle cell trait is characterized by the presence of both normal and abnormal haemoglobin in red blood cells. The rate of exertional collapse is increased in athletes and military recruits who carry the trait, particularly in stressful environmental conditions. The aim of the present study was to investigate microvascular function and its determinants in response to intense exercise at control and warm environmental temperatures in carriers (AS) and non-carriers (AA) of sickle cell trait. METHODS: Nine AS and 11 AA, all healthy physically active young men, randomly participated in four experimental sessions (rest at 21 °C and 31 °C and cycling at 21 °C and 31 °C). All participants performed three exercises bouts as follows: 18-min submaximal exercise; an incremental test to exhaustion; and three 30-s sprints spaced with 20-s resting intervals. RESULTS: Skin Blood Flow (SkBF) was similar at rest between AA and AS. SkBF for all participants was higher at 31 °C than 21 °C. It was significantly higher in the AS group compared to the AA group immediately after exercise, regardless of the environmental conditions. No significant differences in hemorheological parameters, muscle damage or cardiac injury biomarkers were observed between the two groups. Our data also suggest higher oxidative stress for the AS group, with high superoxide dismutase (P = 0.044 main group effect). CONCLUSION: A specific profile is identified in the AS population, with increased microvascular reactivity after maximal exercise in stressful environment and slight pro-/antioxidant imbalance.


Assuntos
Exercício Físico/fisiologia , Temperatura Alta , Microcirculação/fisiologia , Traço Falciforme/sangue , Traço Falciforme/reabilitação , Teste de Esforço , Humanos , Masculino , Pele/irrigação sanguínea , Adulto Jovem
4.
Arch Toxicol ; 89(2): 221-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24819615

RESUMO

Application of omics-based technologies is a widely used approach in research aiming to improve testing strategies for human health risk assessment. In most of these studies, however, temporal variations in gene expression caused by the circadian clock are a commonly neglected pitfall. In the present study, we investigated the impact of the circadian clock on the response of the hepatic transcriptome after exposure of mice to the chemotherapeutic agent cyclophosphamide (CP). Analysis of the data without considering clock progression revealed common responses in terms of regulated pathways between light and dark phase exposure, including DNA damage, oxidative stress, and a general immune response. The overall response, however, was stronger in mice exposed during the day. Use of time-matched controls, thereby eliminating non-CP-responsive circadian clock-controlled genes, showed that this difference in response was actually even more pronounced: CP-related responses were only identified in mice exposed during the day. Only minor differences were found in acute toxicity pathways, namely lymphocyte counts and kidney weights, indicating that gene expression is subject to time of day effects. This study is the first to highlight the impact of the circadian clock on the identification of toxic responses by omics approaches.


Assuntos
Ciclofosfamida/toxicidade , Fígado/efeitos dos fármacos , Transcriptoma , Animais , Relógios Circadianos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Curr Biol ; 24(11): 1248-55, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24856209

RESUMO

Circadian rhythms are responsive to external and internal cues, light and metabolism being among the most important. In mammals, the light signal is sensed by the retina and transmitted to the suprachiasmatic nucleus (SCN) master clock [1], where it is integrated into the molecular oscillator via regulation of clock gene transcription. The SCN synchronizes peripheral oscillators, an effect that can be overruled by incoming metabolic signals [2]. As a consequence, peripheral oscillators can be uncoupled from the master clock when light and metabolic signals are not in phase. The signaling pathways responsible for coupling metabolic cues to the molecular clock are being rapidly uncovered [3-5]. Here we show that insulin-phosphatidylinositol 3-kinase (PI3K)-Forkhead box class O3 (FOXO3) signaling is required for circadian rhythmicity in the liver via regulation of Clock. Knockdown of FoxO3 dampens circadian amplitude, an effect that is rescued by overexpression of Clock. Subsequently, we show binding of FOXO3 to two Daf-binding elements (DBEs) located in the Clock promoter area, implicating Clock as a transcriptional target of FOXO3. Transcriptional oscillation of both core clock and output genes in the liver of FOXO3-deficient mice is affected, indicating a disrupted hepatic circadian rhythmicity. Finally, we show that insulin, a major regulator of FOXO activity [6-9], regulates Clock levels in a PI3K- and FOXO3-dependent manner. Our data point to a key role of the insulin-FOXO3-Clock signaling pathway in the modulation of circadian rhythms.


Assuntos
Proteínas CLOCK/genética , Ritmo Circadiano , Fatores de Transcrição Forkhead/genética , Fosfatidilinositol 3-Quinase/genética , Transdução de Sinais , Animais , Proteínas CLOCK/metabolismo , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Insulina/genética , Insulina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Fosfatidilinositol 3-Quinase/metabolismo
6.
Handb Clin Neurol ; 112: 921-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23622302

RESUMO

Obstetrical brachial plexus palsy is considered to be the result of a trauma during the delivery, even if there remains some controversy surrounding the causes. Although most babies recover spontaneously in the first 3 months of life, a small number remains with poor recovery which requires surgical brachial plexus exploration. Surgical indications depend on the type of lesion (producing total or partial palsy) and particularly the nonrecovery of biceps function by the age of 3 months. In a global palsy, microsurgery will be mandatory and the strategy for restoration will focus first on hand reinnervation and secondarily on providing elbow flexion and shoulder stability. Further procedures may be necessary during growth in order to avoid fixed contractured deformities or to give or increase strength of important muscle functions like elbow flexion or wrist extension. The author reviews the history of obstetrical brachial plexus injury, epidemiology, and the specifics of descriptive and functional anatomy in babies and children. Clinical manifestations at birth are directly correlated with the anatomical lesion. Finally, operative procedures are considered, including strategies of reconstruction with nerve grafting in infants and secondary surgery to increase functional capacity at later ages. However, normal function is usually not recovered, particularly in total brachial plexus palsy.


Assuntos
Traumatismos do Nascimento/etiologia , Neuropatias do Plexo Braquial/etiologia , Plexo Braquial/lesões , Adulto , Traumatismos do Nascimento/fisiopatologia , Traumatismos do Nascimento/cirurgia , Plexo Braquial/fisiopatologia , Plexo Braquial/cirurgia , Neuropatias do Plexo Braquial/fisiopatologia , Neuropatias do Plexo Braquial/cirurgia , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado do Tratamento
9.
PLoS One ; 6(8): e23447, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21858120

RESUMO

Despite the sequence and structural conservation between cryptochromes and photolyases, members of the cryptochrome/photolyase (flavo)protein family, their functions are divergent. Whereas photolyases are DNA repair enzymes that use visible light to lesion-specifically remove UV-induced DNA damage, cryptochromes act as photoreceptors and circadian clock proteins. To address the functional diversity of cryptochromes and photolyases, we investigated the effect of ectopically expressed Arabidopsis thaliana (6-4)PP photolyase and Potorous tridactylus CPD-photolyase (close and distant relatives of mammalian cryptochromes, respectively), on the performance of the mammalian cryptochromes in the mammalian circadian clock. Using photolyase transgenic mice, we show that Potorous CPD-photolyase affects the clock by shortening the period of behavioral rhythms. Furthermore, constitutively expressed CPD-photolyase is shown to reduce the amplitude of circadian oscillations in cultured cells and to inhibit CLOCK/BMAL1 driven transcription by interacting with CLOCK. Importantly, we show that Potorous CPD-photolyase can restore the molecular oscillator in the liver of (clock-deficient) Cry1/Cry2 double knockout mice. These data demonstrate that a photolyase can act as a true cryptochrome. These findings shed new light on the importance of the core structure of mammalian cryptochromes in relation to its function in the circadian clock and contribute to our further understanding of the evolution of the cryptochrome/photolyase protein family.


Assuntos
Relógios Circadianos/fisiologia , Criptocromos/metabolismo , Desoxirribodipirimidina Fotoliase/metabolismo , Potoroidae/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Células COS , Células Cultivadas , Chlorocebus aethiops , Relógios Circadianos/genética , Criptocromos/deficiência , Criptocromos/genética , Desoxirribodipirimidina Fotoliase/genética , Células HEK293 , Humanos , Immunoblotting , Fígado/metabolismo , Luciferases/genética , Luciferases/metabolismo , Medições Luminescentes/métodos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Células NIH 3T3 , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
10.
ENFURO: Rev. Asoc. Esp. A.T.S. Urol ; (115): 5-7, jul.-sept. 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-95274

RESUMO

Tras un primer estudio de 52 valoraciones de enfermería realizadas al ingreso de pacientes urológicos, acogidos al modelo de M. Gordon,se observó que el 70% de las valoraciones omitían el patrón sexualidad. A continuación se llevó a cabo estudio descriptivo sobre la función eréctil en pacientes que iban a ser intervenidos de alguna patología prostática, el estudio indicó que el 90% de los pacientes sometidosa estudio tienen una disfunción eréctil severa. Con estos estudios nos damos cuenta de la importancia de la valoración del patrón sexualidad en especial en los pacientes urológicos, para poder planificar intervenciones futuras con el paciente (AU)


After a first study of 52 realised valuations of infirmary to the entrance of urologic patients, refugees to the model of M. Gordon, wereobserved that 70% of the valuations omitted the landlord sexuality. Next descriptive study was carried out on the erectil function in patients who were going to be taken part of some prostate pathology, the study indicated that 90% of the patients put under study have a severe erectil dysfunction. With these studies we occur to account of the importance of the valuation of landlord sexuality is special in the urologic patients, to be able to plan future interventions with the patient (AU)


Assuntos
Humanos , Masculino , Disfunção Erétil/epidemiologia , Doenças Prostáticas/diagnóstico , Testes Diagnósticos de Rotina/métodos , Anamnese/normas , Diagnóstico de Enfermagem/métodos
11.
ENFURO: Rev. Asoc. Esp. A.T.S. Urol ; (113): 9-14, ene.-mar. 2010. ilus
Artigo em Espanhol | IBECS | ID: ibc-95263

RESUMO

Desde septiembre de 2007 hasta junio de 2009 se ha realizado en nuestra Unidad de Gestión Clínica un total de 72 intervenciones de prostatectomía radical robótica (PRR). Los resultados han sido muy satisfactorios: disminución del sangrado posquirúrgico; bajada significativa de la estancia media hospitalaria (2,5 días); una más rápida recuperación del paciente y mejores tasas de función eréctil. La técnica quirúrgica se ejecuta con un robot Da Vinci, serie S, de cuatro brazos. Partiendo de un caso clínico, un paciente diagnosticado en nuestro Servicio de cáncer de próstata, se exponen los cuidados que presta el personal de enfermería en un caso de PRR una vez que llega a la planta hasta su alta hospitalaria, así como la evolución seguida por el paciente.El modelo de cuidados que se sigue se basa en los once patrones funcionales de Majori Gordon. Por último, se resalta el papel que juega en este tipo de cirugía tanto enfermería domiciliaria como de Atención Primaria (AU)


Since September 2007 until June 2009 a total of 72 interventions of Robotic Radical Prostatectomy Radical Robótica (RRP) have been carried out in our Unit of Clinical Management. The results have been very satisfactory: decrease of the postsurgical bleeding; significant descent of the hospital average stay (2,5 days); a faster recovery of the patient and better rates of erectile function. The surgical technique is executed witha robot Da Vinci, series S, of four arms.Starting from a clinical case, a patient diagnosed in our Service of cancer of prostate, the cares that the staff of nursery in a case ofRRP are exposed once he arrives to the medical ward up to his hospital discharge, as well as the evolution followed by the patient.The model of cares that is followed is based on the eleven functional patterns of Majori Gordon. Finally, domiciliary nursing and Primary Care are highlighted for roles that they play (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Cuidados de Enfermagem/métodos , Robótica , Atenção Primária à Saúde/métodos , Diagnóstico de Enfermagem/métodos , Fatores de Risco
13.
J Med Genet ; 46(7): 458-64, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19357115

RESUMO

BACKGROUND: Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene have been identified in families with autosomal dominant Parkinson's disease (ADPD), the most common of which is the p.G2019S substitution that has been found at varying frequencies worldwide. Because of the size of the LRRK2 gene, few studies have analysed the entire gene in large series of ADPD families. METHODS: We performed extensive mutation analyses of all 51 coding exons of the LRRK2 gene in index cases from 226 Parkinson's disease families compatible with autosomal dominant inheritance, mostly from France (n = 182) and North Africa (n = 14). RESULTS: We found 79 sequence variants, 29 of which were novel. Eight potentially or proven pathogenic mutations were found in 22 probands (9.7%). There were four novel amino acid substitutions that are potentially pathogenic (p.S52F, p.N363S, p.I810V, p.R1325Q) and two novel variants, p.H1216R and p.T1410M, that are probably not causative. The common p.G2019S mutation was identified in 13 probands (5.8%) including six from North Africa (43%). The known heterozygous p.R1441H and p.I1371V mutations were found in two probands each, and the p.E334K variant was identified in one single patient. Most potentially or proven pathogenic mutations were located in the functional domains of the Lrrk2 protein. CONCLUSION: This study leads us to conclude that LRRK2 mutations are a common cause of autosomal dominant Parkinson's disease in Europe and North Africa.


Assuntos
Transtornos Parkinsonianos/genética , Proteínas Serina-Treonina Quinases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , População Negra/genética , Distribuição de Qui-Quadrado , Análise Mutacional de DNA/métodos , Feminino , Frequência do Gene , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Masculino , Pessoa de Meia-Idade , Mutação , Transtornos Parkinsonianos/diagnóstico , Linhagem , População Branca/genética
14.
Chemistry ; 14(36): 11415-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19006143

RESUMO

Even if biocatalysis is finding increasing application, it still has to gain widespread use in synthetic chemistry. Reasons for this are limitations that enzymes have with regard to substrate range, reaction scope, and insufficient selectivity with unnatural compounds. These shortcomings can be challenged by enzyme and/or substrate engineering, which are employed to alter substrate specificity and enhance the enzyme selectivity toward unnatural substrates. Herein, these two approaches are coupled to improve the hydroxynitrile lyase catalyzed synthesis of 2-hydroxy-(4'-oxocyclohexyl)acetonitrile (4). The ketone functionality is masked as an enol ether, and the oxynitrilase of Hevea brasiliensis is engineered towards this masked substrate to give the product with a high optical purity and to drastically lower the amount of enzyme needed.


Assuntos
Acetonitrilas/síntese química , Aldeído Liases/química , Acetonitrilas/química , Aldeído Liases/metabolismo , Substituição de Aminoácidos , Sequência de Bases , Biocatálise , Simulação por Computador , Hevea/enzimologia , Mutação , Estrutura Terciária de Proteína , Estereoisomerismo , Relação Estrutura-Atividade , Especificidade por Substrato
15.
Biomed Tech (Berl) ; 53(1): 16-24, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18251707

RESUMO

Both ethical and economic restrictions limit the availability of porcine hearts for in vitro perfusion experiments. Therefore, we tested the feasibility of multiple use of in vitro perfused working hearts for electrophysiological and metabolic investigations. Pig hearts (n=7) rejected for originally planned haemodynamic measurements because of exclusion criteria were perfused in a four-chamber working heart mode. All hearts were kept in steady-state conditions on a low haemodynamic level over 2 h during 75-channel ECG recordings and NADH fluorescence measurements before and after norepinephrine (NE) was administered. QRS and QT interval durations were in a range comparable to in vitro studies and, like QRS and T amplitudes, were found to be sensitive markers of the changing condition of the isolated heart preparation, as myocardial oedema leads to prolonged QRS and QT intervals and declining ECG voltage amplitudes. A change in NADH fluorescence following NE administration was observed in the first 150 min of perfusion, but not later. Considering a time frame of 120 min, multiple use of isolated perfused porcine hearts with low-level haemodynamics may allow a broad spectrum of investigations and could therefore represent a possibility of overcoming the restricted availability of porcine hearts.


Assuntos
Mapeamento Potencial de Superfície Corporal/métodos , Eletrofisiologia/métodos , Metabolismo Energético/fisiologia , Coração/fisiologia , Modelos Animais , Reperfusão Miocárdica/métodos , Projetos de Pesquisa , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Cães , Técnicas In Vitro
16.
J Clin Densitom ; 10(4): 386-90, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17993401

RESUMO

This study aims to determine the prevalence of Type 2 diabetes in women with osteoporosis and estimate the odds ratio (OR) of osteoporosis in women with Type 2 diabetes using Bayesian inference. This is a case-control study design that looked into prevalence of diabetes among 582 female patients who had normal bone mineral density (BMD) and 598 female patients with osteoporosis. The subjects included women at least 30 yr of age who had their BMD measured in the lumbar spine and femoral neck using dual-energy X-ray absorptiometry at a tertiary referral center in Manila, Philippines. Prevalence of Type 2 diabetes in subjects with osteoporosis is 22.41%, whereas 19.07% of the subjects with normal BMD had diabetes. The odds of developing osteoporosis is 22.54% higher for Type 2 diabetic subjects. Patients with osteoporosis were older than subjects with normal BMD by almost 10 yr. Of the diabetic osteoporotic patients, 44.78% were physically active compared with 20.72% diabetics with normal BMD. Most of the diabetics (60.36%) with normal BMD were obese, whereas majority of diabetic osteoporotics (64.93%) have normal body mass index (BMI). Less than 10% of both diabetic osteoporotics and diabetics with normal BMD have ever undergone hormone replacement therapy. Of the 598 subjects with osteoporosis, 124 (20.74%) had suffered from fragility fractures. When controlling for physical activity and BMI, the odds of developing osteoporosis was 21.73% and 53.89% higher for Type 2 diabetics, respectively. In considering all possible confounders and effect modifiers (age, physical activity, BMI, and hormone replacement therapy) in the model which made use of a diffuse normal prior distribution, the estimate for OR (Model 1) is 0.67. A separate analysis excluding modifiable confounders (Model 2) gave the measure of association an equal likelihood of diabetes being a protective factor or a risk factor. The crude OR indicated that Type 2 diabetes is a risk factor for osteoporosis. However, when identified confounders were included in the model, the direction of the relationship changed. Considering the credible intervals (95% credible interval in both models), the study concluded that diabetes is indeed a protective factor for osteoporosis. Results of the study may have potential limitations. There are sources of bias that have been identified--selection bias where patients included in the study were referred by primary care givers for a specified reason as well as misclassification and recall biases on certain information such as type and duration of physical activity. Diabetes is a protective factor for osteoporosis in this referred population of women. However, with the well-known diabetes-related factors, that is, microvascular complications, visual acuity, and risk for fall, one should still strongly consider assessing and screening for osteoporosis and fracture risk reduction in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Osteoporose/complicações , Osteoporose/diagnóstico , Absorciometria de Fóton/métodos , Adulto , Fatores Etários , Idoso , Teorema de Bayes , Índice de Massa Corporal , Densidade Óssea , Feminino , Fraturas Ósseas , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Razão de Chances , Resultado do Tratamento
17.
Biomed Tech (Berl) ; 52(2): 193-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17408379

RESUMO

Autofluorescence of tissues and organs is an indicator of the physiological state of cells. The aim of the study was to investigate whether fluorimetric determination of the redox state of the ex vivo perfused pig heart can provide fast online detection of progressive changes in heart muscle tissue. Measurements on six organs perfused in a four-chamber working heart model were performed using a spectroscopic method exploiting the specific and different fluorescence lifetimes of intrinsic fluorophores such as NADH and flavins and providing a means of internal signal referencing. It was shown that the redox potential of heart muscle tissue can be assessed by fluorescence measurement. In the steady-state phase of the beating heart, spectroscopic measurements revealed a change in redox state from an initial constant level to a continuous decrease, accompanied by a decrease in heart performance and indications of changes in electrolyte equilibrium (K(+) concentration). At the same time, troponin I levels in the perfusate increased. The results indicate that fluorimetric determination of heart muscle metabolic activity yields reliable information about the functional status of the ex vivo heart and may be advantageous for the optimisation of ex vivo organ models.


Assuntos
Flavinas/metabolismo , Miocárdio/metabolismo , NAD/metabolismo , Espectrometria de Fluorescência/métodos , Troponina I/metabolismo , Animais , Perfilação da Expressão Gênica/métodos , Técnicas In Vitro , Oxirredução , Suínos
19.
RNA ; 11(8): 1317-28, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16043510

RESUMO

Protein synthesis is initiated on ribosomal subunits. However, it is not known how 70S ribosomes are dissociated into small and large subunits. Here we show that 70S ribosomes, as well as the model post-termination complexes, are dissociated into stable subunits by cooperative action of three translation factors: ribosome recycling factor (RRF), elongation factor G (EF-G), and initiation factor 3 (IF3). The subunit dissociation is stable enough to be detected by conventional sucrose density gradient centrifugation (SDGC). GTP, but not nonhydrolyzable GTP analog, is essential in this process. We found that RRF and EF-G alone transiently dissociate 70S ribosomes. However, the transient dissociation cannot be detected by SDGC. IF3 stabilizes the dissociation by binding to the transiently formed 30S subunits, preventing re-association back to 70S ribosomes. The three-factor-dependent stable dissociation of ribosomes into subunits completes the ribosome cycle and the resulting subunits are ready for the next round of translation.


Assuntos
Biossíntese de Proteínas , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Guanosina Trifosfato/metabolismo , Cinética , Fator G para Elongação de Peptídeos/metabolismo , Fator de Iniciação 3 em Procariotos/metabolismo
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