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1.
J Visc Surg ; 155(4): 259-264, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29289460

RESUMO

Complications related to energy sources in the operating room are not well-recognized or published, despite occasionally dramatic consequences for the patient and the responsible surgeon. The goal of this study was to evaluate the risks and consequences related to use of energy sources in the operating room. PATIENTS AND METHODS: Between 2009 and 2015, 876 adverse events related to health care (AERHC) linked to energy sources in the operating room were declared in the French experience feedback data base "REX". We performed a descriptive analysis of these AERHC and analyzed the root causes of these events and of the indications for non-elective repeat operations, for each energy source. RESULTS: Five different energy sources were used, producing 876 declared AERHC: monopolar electrocoagulation: 614 (70%) AERHC, advanced bipolar coagulation (thermofusion): 137 (16%) AERHC, ultrasonic devices: 69 (8%) AERHC, traditional bipolar electrocoagulation: 32 AERHC, and cold light: 24 AERHC. The adverse events reported were skin burns (27.5% of AERHC), insulation defects (16% of AERHC), visceral burns or perforation (30% of AERHC), fires (11% of AERHC), bleeding (7.5% of AERHC) and misuse or miscellaneous causes (8% of AERHC). For the five energy sources, the root causes were essentially misuse, imperfect training and/or cost-related reasons regarding equipment purchase or maintenance. One hundred and forty-six non-elective procedures (17% of AERHC) were performed for complications related to the use of energy sources in the operating room. CONCLUSION: This study illustrates the risks related to the use of energy sources on the OR and their consequences. Most cases were related to persistent misunderstanding of appropriate usage within the medical and paramedical teams, but complications are also related to administrative decisions concerning the purchase and maintenance of these devices.


Assuntos
Eletrocoagulação/efeitos adversos , Eletrocoagulação/instrumentação , Complicações Intraoperatórias/etiologia , Gestão de Riscos , Procedimentos Cirúrgicos Ultrassônicos/efeitos adversos , Procedimentos Cirúrgicos Ultrassônicos/instrumentação , Bases de Dados Factuais , França/epidemiologia , Humanos , Complicações Intraoperatórias/epidemiologia
2.
Am J Transplant ; 17(7): 1723-1728, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28321984

RESUMO

Inclusion of compatible living donor and recipient pairs (CPs) in kidney paired donation (KPD) programs could increase living donor transplantation. We introduce the concept of a reciprocity-based strategy in which the recipient of a CP who participates in KPD receives priority for a repeat deceased donor transplant in the event their primary living donor KPD transplant fails, and then we review the practical and ethical considerations of this strategy. The strategy limits prioritization to CPs already committed to living donation, minimizing the risk of unduly influencing donor behavior. The provision of a tangible benefit independent of the CP's actual KPD match avoids many of the practical and ethical challenges with strategies that rely on finding the CP recipient a better-matched kidney that might provide the CP recipient a future benefit to increase KPD participation. Specifically, the strategy avoids the potential to misrepresent the degree of future benefit of a better-matched kidney to the CP recipient and minimizes delays in transplantation related to finding a better-matched kidney. Preliminary estimates suggest the strategy has significant potential to increase the number of living donor transplants. Further evaluation of the acceptance of this strategy by CPs and by waitlisted patients is warranted.


Assuntos
Seleção do Doador , Rejeição de Enxerto/prevenção & controle , Transplante de Rim/métodos , Doadores Vivos , Participação do Paciente , Obtenção de Tecidos e Órgãos/normas , Idoso , Morte , Feminino , Rejeição de Enxerto/etiologia , Histocompatibilidade , Humanos , Transplante de Rim/efeitos adversos , Masculino , Obtenção de Tecidos e Órgãos/métodos
3.
J Dev Orig Health Dis ; 8(1): 3-7, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28051763

RESUMO

Based on the Developmental Origin of Health and Disease concept, maternal undernutrition has been shown to sensitize adult offspring to metabolic pathologies such as obesity. Using a model of maternal 70% food restriction in pregnant female rats throughout gestation (called FR30), we previously reported that obesity-prone adult male rat offspring displayed hyperleptinemia with modifications in leptin and leptin receptor messenger RNA (mRNA) levels in white adipose tissue (WAT). Apelin is a member of the adipokine family that regulates various aspects of energy metabolism and WAT functionality. We investigated whether apelin and its receptor APJ could be a target of maternal undernutrition. Adult male rat offspring from FR30 dams showed increased plasma apelin levels and apelin gene expression in WAT. Post-weaning high-fat diet led to marked increase in APJ mRNA and protein levels in offspring's WAT. We demonstrate that maternal undernutrition and post-weaning diet have long-term consequences on the apelinergic system of adult male rat offspring.


Assuntos
Tecido Adiposo/metabolismo , Receptores de Apelina/metabolismo , Apelina/metabolismo , Desnutrição/fisiopatologia , Tecido Adiposo/patologia , Animais , Peso Corporal , Metabolismo Energético , Feminino , Leptina/metabolismo , Masculino , Gravidez , Ratos
4.
Am J Physiol Endocrinol Metab ; 308(5): E393-401, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25550282

RESUMO

A close link between intrauterine growth restriction and development of chronic adult diseases such as obesity, diabetes, and hypertension has been established both in humans and animals. Modification of growth velocity during the early postnatal period (i.e., lactation) may also sensitize to the development of metabolic syndrome in adulthood. This suggests that milk composition may have long-lasting programming/deprogramming metabolic effects in the offspring. We therefore assess the effects of maternal perinatal denutrition on breast milk composition in a food-restricted 50% (FR50) rat model. Monosaccharides and fatty acids were characterized by gas chromatography, and proteins were profiled by surface-enhanced laser desorption/ionization-time-of-flight analysis in milk samples from FR50 and control rat dams. Milk analysis of FR50 rats demonstrated that maternal undernutrition decreases lactose concentration and modulates lipid profile at postnatal day 10 by increasing the unsaturated fatty acids/saturated fatty acids and diminishes serotransferrin levels at postnatal day 21. Our data indicate that maternal perinatal undernutrition modifies milk composition both quantitatively and qualitatively. These modifications by maternal nutrition open new perspectives to identify molecules that could be used in artificial milk to protect from the subsequent development of metabolic diseases.


Assuntos
Lactose/metabolismo , Desnutrição/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Doenças Metabólicas/etiologia , Leite/metabolismo , Complicações na Gravidez/metabolismo , Transferrina/metabolismo , Animais , Animais Lactentes , Feminino , Lactação/metabolismo , Masculino , Parto/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Wistar , Fatores de Risco
5.
J Dev Orig Health Dis ; 5(2): 109-20, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24847697

RESUMO

Undernutrition exposure during the perinatal period reduces the growth kinetic of the offspring and sensitizes it to the development of chronic adult metabolic diseases both in animals and in humans. Previous studies have demonstrated that a 50% maternal food restriction performed during the last week of gestation and during lactation has both short- and long-term consequences in the male rat offspring. Pups from undernourished mothers present a decreased intrauterine (IUGR) and extrauterine growth restriction. This is associated with a drastic reduction in their leptin plasma levels during lactation, and exhibit programming of their stress neuroendocrine systems (corticotroph axis and sympatho-adrenal system) in adulthood. In this study, we report that perinatally undernourished 6-month-old adult animals demonstrated increased leptinemia (at PND200), blood pressure (at PND180), food intake (from PND28 to PND168), locomotor activity (PND187) and altered regulation of glycemia (PND193). Cross-fostering experiments indicate that these alterations were prevented in IUGR offspring nursed by control mothers during lactation. Interestingly, the nutritional status of mothers during lactation (ad libitum feeding v. undernutrition) dictates the leptin plasma levels in pups, consistent with decreased leptin concentration in the milk of mothers subjected to perinatal undernutrition. As it has been reported that postnatal leptin levels in rodent neonates may have long-term metabolic consequences, restoration of plasma leptin levels in pups during lactation may contribute to the beneficial effects of cross-fostering IUGR offspring to control mothers. Collectively, our data suggest that modification of milk components may offer new therapeutic perspectives to prevent the programming of adult diseases in offspring from perinatally undernourished mothers.


Assuntos
Lactação , Fenômenos Fisiológicos da Nutrição Pré-Natal , Aldosterona/sangue , Animais , Animais Recém-Nascidos , Fator Natriurético Atrial/metabolismo , Pressão Sanguínea , Composição Corporal , Feminino , Glucose/metabolismo , Frequência Cardíaca , Leptina/sangue , Masculino , Desnutrição/complicações , Gravidez , Ratos Wistar , Fatores de Tempo , Vasopressinas/sangue
6.
J Dev Orig Health Dis ; 4(2): 134-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25054679

RESUMO

Genetic variants in the FTO (fat mass- and obesity-associated) gene have the highest association of all obesity-associated genes. Its placental expression was shown to relate to birth weight, suggesting that it may participate in the control of fetal weight gain. To gain more insight into the implication of FTO in fetal growth, we measured its placental expression in samples including extremes of abnormal fetal growth, such as after intrauterine growth restriction (IUGR) or macrosomia in both rats and humans. In rats, fetal growth was modulated by maternal nutritional modifications. In humans, placental villi were collected from pathological pregnancies (i.e. with IUGR or fetal macrosomia). Placental FTO mRNA expression was reduced by IUGR but was not significantly affected by macrosomia in either rats or humans. Our data suggest that placental FTO may participate in interactions between the in utero environment and the control of fetal growth under IUGR conditions by modulating epigenetic processes.

7.
Bioresour Technol ; 102(2): 1521-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20869237

RESUMO

Glycerol is an agro-industrial residue generated in high amounts during the biodiesel production. The growing production of biodiesel is creating a worldwide glycerol surplus. Therefore, replacing sugar-based feedstock in bioprocesses by glycerol could be potentially attractive. Saccharomyces cerevisiae is one of the most commonly used microorganisms in the agri-food industry and therefore currently produced in large quantities from sugar-based feedstock. Unfortunately, growth of S. cerevisiae strains on glycerol is very low with reported µmax around 0.01 h(-1). This study demonstrates that successive growth of the S. cerevisiae CBS 8066, CEN.PK 113-7 D and Ethanol Red on glycerol as sole carbon source considerably improved the µmax from 0.01 up to 0.2 h(-1). The "adapted strain" CBS 8066-FL20 was kinetically characterized during aerobic and oxygen-limited cultivation in bioreactor and the results discussed in terms of their implication for developing glycerol-based S. cerevisiae bioprocesses.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Glicerol/farmacologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Aerobiose/efeitos dos fármacos , Biomassa , Carbono/farmacologia , Fermentação/efeitos dos fármacos , Cinética , Oxirredução/efeitos dos fármacos , Oxigênio/farmacologia , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/efeitos dos fármacos , Fatores de Tempo
8.
Placenta ; 31(9): 785-91, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20615547

RESUMO

The brain-derived neurotrophic factor (BDNF) has been shown to exert an important role during implantation, placental development, and fetal growth control in mice. Its expression is closely related to the nutritional status in several tissues such as in the nervous system. In a previous study, we demonstrated that maternal undernutrition (MU), during the perinatal life, modified both the BDNF and its functional receptor, the tyrosine kinase receptor B (TrkB) gene expression in the brain of growth-restricted rat offspring during sensitive developmental windows, suggesting that these early modifications may have long-lasting consequences. In the present study, we measured BDNF/TrkB mRNA and protein levels in rat placentas from mothers submitted to a 50% food restriction during gestation, and in human placentas from pregnancies with fetal growth restriction or fetal macrosomia. In the rat, two subtypes of placental TrkB receptors have been identified: the TrkB-FL and TrkB-T1 receptors. We found that MU induced intrauterine growth restriction (IUGR) of fetuses at term and decreased the placental BDNF mRNA and protein levels. Placentae from undernourished mothers exhibited an increased mRNA expression of TrkB-FL whereas both TrkB-FL and TrkB-T1 receptors proteins levels were not modified. In human IUGR placentas, both BDNF and TrkB receptor mRNA expressions were up-regulated. Finally, although neither BDNF nor TrkB mRNA levels were altered by fetal macrosomia alone, BDNF mRNA levels were decreased when macrosomia was associated with maternal type 1 diabetes. These results show that the placental BDNF/TrkB system is modulated in rats and humans during pregnancies with fetal growth perturbations and is affected by the maternal energetic status. These data suggest that this system may exert an important role for the feto-placental unit development and that it may also be implicated in the etiology of pathologies related to placental and fetal growth disturbances.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Retardo do Crescimento Fetal/metabolismo , Receptor trkB/genética , Animais , Feminino , Macrossomia Fetal/metabolismo , Humanos , Desnutrição/fisiopatologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
9.
J Neuroendocrinol ; 21(1): 40-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19094092

RESUMO

Maternal perinatal undernutrition (MPU) modifies the activity of the hypothalamic-pituitary-adrenal axis and sensitises to the development of metabolic and cognitive adult diseases. Because the hypothalamus and hippocampus are involved in the regulation of neuroendocrine activity, energy metabolism and cognition, we hypothesised that a maternal 50% food restriction (FR50) from day 14 of pregnancy (E14) until postnatal day 21 (P21) would affect the development of these structures in male rat offspring. Protein and mRNA levels of brain-derived neurotrophic factor (BDNF) and cell proliferation [analysed by 5-bromodeoxyuridine (BrdU) incorporation] were compared in both control and FR50 rats from E21 to P22. Although the pattern of the evolution of BDNF concentration and cell proliferation throughout development was not strikingly different between groups, several disturbances at specific developmental stages were observed. FR50 rats exhibited a delayed increase of hippocampal BDNF content whereas, in the hypothalamus, BDNF level was augmented from E21 to P14 and associated, at this latter stage, with an increased mRNA expression of TRkB-T2. In both groups, a correlation between BDNF content and the number of BrdU positive cells was noted in the dentate gyrus, whereas opposite variations were observed in CA1, CA2 and CA3 layers, and in the arcuate and ventromedial nuclei. In the hippocampus, P15-FR50 rats showed an increased number of BrdU positive cells in all regions, whereas, at P22, a decrease was observed in the CA2. In the hypothalamus, between E21 and P8, MPU increases the number of BrdU positive cells in all regions analysed and, until P15, marked differences were noticed in the median eminence, the paraventricular nucleus and the arcuate nucleus. Taken together, the results obtained in the present study show that MPU changes the time course of production of BDNF and cell proliferation in specific hippocampal and hypothalamic areas during sensitive developmental windows, suggesting that these early perinatal modifications may have long-lasting consequences.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células , Hipocampo/embriologia , Hipocampo/crescimento & desenvolvimento , Hipotálamo/embriologia , Hipotálamo/crescimento & desenvolvimento , Desnutrição , Animais , Período Crítico Psicológico , Feminino , Hipocampo/anatomia & histologia , Hipotálamo/anatomia & histologia , Masculino , Gravidez , Ratos , Ratos Wistar , Receptor trkB/metabolismo
10.
Horm Metab Res ; 40(4): 257-61, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18548384

RESUMO

Maternal undernutrition leads to intrauterine growth retardation and predisposes to the development of pathologies in adulthood. The hypothalamo-pituitary-adrenal axis is a major target of early-life programming. We showed previously that perinatal maternal 50% food restriction leads to hypothalamo-pituitary-adrenal axis hyperactivity and disturbs glucocorticoid feedback in adult male rats. To try to better understand these alterations, we studied several factors involved in corticosterone sensitivity. We showed that unlike the restricted expression of 11 beta-HSD2 mRNA, the 11 beta-HSD1, glucocorticoid, and mineralocorticoid receptor genes are widely distributed in rat. In contrast to the hypothalamus, we confirmed that maternal undernutrition modulates hippocampal corticosterone receptor balance and leads to increased 11 beta-HSD1 gene expression. In the pituitary, rats exhibited a huge increase in both mRNA and mineralocorticoid receptor binding capacities as well as decreased 11 beta-HSD1/11 beta-HSD2 gene expression. Using IN SITU hybridization, we showed that the mineralocorticoid receptor gene was expressed in rat corticotroph cells and by other adenopituitary cells. In the adrenal gland, maternal food restriction decreased 11beta-HSD2 mRNA. This study demonstrated that maternal food restriction has both long-term and tissue-specific effects on gene expression of factors involved in glucocorticoid sensitivity and that it could contribute, via glucocorticoid excess, to the development of adult diseases.


Assuntos
11-beta-Hidroxiesteroide Desidrogenases/biossíntese , Animais Recém-Nascidos/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Desnutrição/metabolismo , Receptores de Glucocorticoides/biossíntese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/biossíntese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/biossíntese , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , Animais , Sistema Hipotálamo-Hipofisário/anatomia & histologia , Sistema Hipotálamo-Hipofisário/enzimologia , Hibridização In Situ , Masculino , Sistema Hipófise-Suprarrenal/anatomia & histologia , Sistema Hipófise-Suprarrenal/enzimologia , Sistema Hipófise-Suprarrenal/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Wistar , Receptores de Mineralocorticoides/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Brain ; 129(Pt 9): 2332-40, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16672289

RESUMO

Recessive ataxias are a heterogeneous group of diseases. We identified a group of 23 French-Canadian cases belonging to 17 families affected by an autosomal recessive spastic ataxia associated with frequent white matter changes. The fact that 59% of these families have a genealogical relationship to the Portneuf County of Quebec suggests that this is a new form of ataxia with a regional founder effect. All cases present with cerebellar ataxia and spasticity. There is great intrafamilial and interfamilial variability, as illustrated by the spectrum of age of diagnosis (range: 2-59 years, mean: 15.0) and the presence of white matter changes on MRI in 52.4% of cases. The more severe cases have spasticity from birth, scoliosis, dystonia and cognitive impairment and were considered cases of cerebral palsy. Brain MRI constantly shows cerebellar atrophy, which in some cases may be associated with cortical atrophy, leucoencephalopathy and corpus callosum thinning. A genome wide scan uncovered linkage of three families to marker D2S2321 localized on chromosome 2q33-34. Linkage analysis confirmed that all families are linked to the same region [multipoint log of the odds (LOD) score of 5.95]. Haplotype analysis and allele sharing suggest that one common mutation may account for 97% of carrier chromosomes in Quebec. The uncovering of the mutated gene may point to a common pathway for pyramidal and cerebellar degeneration as both are often observed in recessive ataxias and complicated paraplegias.


Assuntos
Ataxia Cerebelar/genética , Cromossomos Humanos Par 2/genética , Paraplegia/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Adulto , Atrofia/genética , Encéfalo/patologia , Ataxia Cerebelar/patologia , Criança , Pré-Escolar , Estudos de Coortes , Corpo Caloso/patologia , Saúde da Família , Feminino , Genes Recessivos/genética , Ligação Genética/genética , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Linhagem , Fenótipo , Quebeque
12.
J Occup Environ Hyg ; 2(9): 456-61, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16091349

RESUMO

During the thermal degradation of 1,6-hexamethylenediiso- cyanate-based (HDI) car paint, the eight most abundant isocyanates generated are isocyanic acid, methyl isocyanate, ethyl isocyanate, propyl isocyanate, butyl isocyanate, pentyl isocyanate, hexyl isocyanate, and 1,6-hexamethylenediisocyanate. For the first time, a method using solvent-free samplers is proposed and validated for the simultaneous sampling of all these isocyanates. The sampling efficiency during thermal degradation of car paint can be affected by the formation of dust and aerosols and by the emission of many chemicals, such as isocyanic acid, anhydrides, amines, and alcohols that consume the reagent or interfere in the derivatization procedure. Sampling was performed using cassettes containing two 1-(2-methoxyphenyl)piperazine (MOPIP)-coated glass fiber filters (MFs) (approximately 4.9 mg per filter) and compared with bubblers containing 15 mL of MOPIP solution in toluene (1.0 mg/mL(-1)) and with bubblers backed with MFs. A DIN 53436 laboratory scale furnace was used to generate the isocyanates under thermal degradation conditions. For an aliphatic isocyanate concentration of approximately 42 microg(NCO) m(-3), no significant difference in sampling efficiency was observed between the three techniques studied, thus confirming the sampling efficiency of the MFs. The samples were analyzed using high-performance liquid chromatography coupled with electrospray/tandem mass spectrometry. Quantification was performed in daughter mode monitoring (MOPIP+H)(+) fragments. For concentrations between 0.013 microg(NCO) mL(-1) and 0.52 microg(NCO) mL(-1) for the monoisocyanates, and between 0.026 microg(NCO) mL(-1) and 1.04 microg(NCO) mL(-1) for the HDI, the correlation coefficients were in the 0.9974-0.9996 range (n = 18). Analytical reproducibility and precision were better than 95.4% and 94.9%, respectively, for all the isocyanates. The instrumental detection limits, defined as three times the standard deviation measured at the lowest point on the calibration curve were in the 1.8-3.0 ng(NCO) mL(-1) range (n = 8), which corresponds to about 0.37-0.60 microg(NCO) m(-3) for a 15-L air sample when the filters are desorbed in 3 mL.


Assuntos
Poluentes Ocupacionais do Ar/análise , Cianatos/análise , Monitoramento Ambiental/instrumentação , Isocianatos/análise , Exposição Ocupacional/análise , Pintura/análise , Automóveis , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Temperatura Alta/efeitos adversos , Humanos , Peso Molecular , Piperazinas , Medição de Risco , Solventes
13.
J Am Soc Mass Spectrom ; 15(9): 1315-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15337511

RESUMO

Thermoanalytical techniques are currently used for the analysis of additives contained in polymers that cannot be easily dissolved, extracted, or hydrolyzed. With these techniques, the polymers are heated to liberate the additives trapped in the polymer matrix. If the polymer is heated slowly, up to its thermal degradation, the technique is called temperature-programmed pyrolysis (TPPy). For TPPy experiments, mass spectrometry is generally used as the detection method. The ionization sources commonly used in mass spectrometry, such as CI and EI, can cause fragmentation during the ionization process. Fragmentation decreases the sensitivity of the molecular ions and increases the risks of interferences with the compounds coming from the matrix. An energy-tunable ionization technique, called metastable atom bombardment (MAB), is proposed for TPPy/MS experiments. With this ionization source, the energy of ionization depends on the metastable gas used. With low-energy metastable gases such as Xe or N(2), fragmentation is reduced compared to CI, whereas with medium-energy metastable gases such as Ar or Kr, the fragmentation is similar to that observed with CI. TPPy/MAB-MS was performed on an unknown polyurethane-based car paint. The detection of molecular ions and characteristic fragments with MAB(N(2)) led to the identification of two light stabilizers: Bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate (BPPS) and 2-(2H-benzotriazol-2-yl)-4,6- di-tert-pentylphenol (PTPP). Using MAB(Ar) to simulate CI, the molecular ion and one of the two characteristic fragments of BPPS were not detected, thus confirming the advantage of using MAB(N(2)) ionization for TPPy/MS experiments.

14.
J Endocrinol ; 181(2): 291-6, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15128277

RESUMO

There is growing evidence that prenatal adversities could be implicated in foetal programming of adult chronic diseases. Since maternal stress is known to disturb the foetal glucocorticoid environment, we examined the consequences of prenatal stress on foetal growth, on glucose-insulin metabolism and on feeding behaviour in the aged male rat. In foetuses at term, maternal stress reduced body, adrenal and pancreas weight as well as plasma corticosterone and glucose levels. In aged male rats (24 months of age), prenatal stress induced hyperglycaemia and glucose intolerance and decreased basal leptin levels. Moreover, after a fasting period, they showed an increased food intake. These data suggest that maternal stress induces a long-lasting disturbance in feeding behaviour and dysfunctions related to type 2 diabetes mellitus. This programming could be linked to the early restricted foetal growth and to the adverse glucocorticoid environment in utero.


Assuntos
Envelhecimento/fisiologia , Comportamento Alimentar , Retardo do Crescimento Fetal/etiologia , Intolerância à Glucose/etiologia , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/complicações , Glândulas Suprarrenais/anatomia & histologia , Animais , Peso ao Nascer , Glicemia/análise , Corticosterona/sangue , Feminino , Leptina/sangue , Masculino , Tamanho do Órgão , Pâncreas/anatomia & histologia , Gravidez , Ratos , Ratos Sprague-Dawley
15.
Eur Respir J ; 23(2): 300-3, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14979507

RESUMO

Inhalation challenges with occupational agents are used to confirm the aetiology of occupational asthma. It has been proposed that using closed-circuit equipment rather than the realistic challenge method would improve the methodology of these tests. Changes in forced expiratory volume in one second (FEV1) were examined in 496 subjects with "positive specific inhalation challenges", i.e. changes in FEVI of > or = 20% after exposure to an occupational agent, including 357 subjects exposed by the realistic method, 108 using the closed-circuit method and 31 by both methods. For immediate reactions, 18 of 95 (19%) showed changes in FEV1 of > or = 30% with the closed-circuit method, whereas a significantly larger proportion, i.e. 77 of 200 (38.5%), showed such changes using the realistic method. As regards nonimmediate reactions, changes in FEV1 of > or = 30% occurred in 16 of 43 (37%) cases with the closed-circuit method as compared to a larger proportion, i.e. 87 of 180 (48%) cases, using the realistic method. This favourable effect was significantly more pronounced in workers with higher levels of bronchial hyperresponsiveness to methacholine. It is concluded that, for agents that can be generated using the closed-circuit method, use of such apparatus results in a smaller proportion of exaggerated bronchoconstriction than does the realistic method, this being particularly true for low-molecular weight agents.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Alérgenos/toxicidade , Asma/induzido quimicamente , Testes de Provocação Brônquica/métodos , Broncoconstrição/efeitos dos fármacos , Broncoconstritores/toxicidade , Doenças Profissionais/induzido quimicamente , Administração por Inalação , Asma/diagnóstico , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/diagnóstico , Poeira , Farinha/toxicidade , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Hipersensibilidade Imediata/induzido quimicamente , Hipersensibilidade Imediata/diagnóstico , Isocianatos/toxicidade , Cloreto de Metacolina , Doenças Profissionais/diagnóstico , Valor Preditivo dos Testes , Estudos Retrospectivos
16.
Cell Mol Life Sci ; 60(2): 382-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12678501

RESUMO

Dietary long-chain polyunsaturated fatty acids are known to influence brain levels of the endocannabinoid anandamide in newborn pigs and mice. Furthermore, endocannabinoids were shown to control pup suckling and body weight in mice, and food intake in adult rodents. Here we determined the effect of maternal under-nutrition during gestation, lactation, or both, on body weight, and on the levels of endocannabinoids and expression of cannabinoid CB1 receptors and fatty acid amide hydrolase in the hypothalamus of rat pups at weaning (21 days old) or adult rats (4 months old). Maternal under-nutrition resulted in a striking decrease in body weight of weaning rats, paralleled by a decrease in the hypothalamic levels of the endocannabinoid anandamide, but not of 2-arachidonoylglycerol. No significant change in the hypothalamic expression of either cannabinoid CB1 receptors or fatty acid amide hydrolase mRNA was detected in any of the three groups of weaned pups. The decrease in pup body weight and hypothalamic anandamide levels was not observable in 4-month-old rats from any of the three groups. These data suggest that maternal under-nutrition causes a decrease in hypothalamic anandamide levels and loss of body weight, and confirm a crucial role for endocannabinoid signalling in neonatal development.


Assuntos
Animais Recém-Nascidos , Peso Corporal , Ácidos Graxos Insaturados/metabolismo , Hipotálamo/metabolismo , Distúrbios Nutricionais/complicações , Complicações na Gravidez , Prenhez , Amidoidrolases/metabolismo , Animais , Animais Lactentes , Moduladores de Receptores de Canabinoides , Endocanabinoides , Feminino , Gravidez , Ratos , Ratos Wistar , Receptores de Canabinoides , Receptores de Droga/metabolismo
17.
Horm Res ; 59(3): 142-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12637794

RESUMO

OBJECTIVE AND METHODS: We investigated the effects of individual natriuretic peptides (atrial natriuretic peptide, ANP; brain natriuretic peptide, BNP, and C-type natriuretic peptide, CNP) on rat corticotropin-releasing factor stimulated adrenocorticotropic hormone (ACTH) secretion by the pituitary gland of 21-day-old rat fetuses in vitro and on pro-opiomelanocortin gene expression using in situ hybridization. RESULTS: Graded concentrations of ANP, BNP, or CNP (10(-10), 10(-9), and 10(-8) mol/l) induced a log dose dependent inhibition of ACTH secretion induced by rat corticotropin-releasing factor (10(-10) mol/l). These natriuretic peptides showed equipotent effects on a molar basis. Moreover, ANP, BNP, or CNP at 10(-10) mol/l reduced significantly the pituitary pro-opiomelanocortin mRNA expression. In addition, the immunoreactive ANP, BNP, and CNP cells were localized in the anterior lobe, but not in the intermediate lobe of the fetal pituitary gland. CONCLUSIONS: These data suggest that the fetal pituitary gland may be both a source and a target for natriuretic peptides that might control ACTH synthesis and release via an endocrine and/or paracrine mechanism. The natriuretic peptides could participate, as well as glucocorticoids, in the control of the corticotropin-stimulating activity of the fetal rat in late gestation.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Fator Natriurético Atrial/farmacologia , Peptídeo Natriurético Encefálico/farmacologia , Peptídeo Natriurético Tipo C/farmacologia , Hipófise/metabolismo , Pró-Opiomelanocortina/biossíntese , RNA Mensageiro/biossíntese , Animais , Hormônio Liberador da Corticotropina/farmacologia , Feminino , Feto/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Hibridização In Situ , Hipófise/citologia , Gravidez , Radioimunoensaio , Ratos , Ratos Wistar , Proteínas Recombinantes/farmacologia
18.
J Endocrinol ; 174(1): 37-43, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12098661

RESUMO

Fetal intrauterine growth restriction (IUGR) is a frequently occurring and serious complication of pregnancy. Infants exposed to IUGR are at risk for numerous perinatal morbidities, including hypoglycemia in the neonatal period, as well as increased risk of later physical and/or mental impairments, cardiovascular disease and non-insulin-dependent diabetes mellitus. Fetal growth restriction most often results from uteroplacental dysfunction during the later stage of pregnancy. As glucose, which is the most abundant nutrient crossing the placenta, fulfills a large portion of the fetal energy requirements during gestational development, and since impaired placental glucose transport is thought to result in growth restriction, we investigated the effects of maternal 50% food restriction (FR50) during the last week of gestation on rat placental expression of glucose transporters, GLUT1, GLUT3 and GLUT4, and on plasma glucose content in both maternal and fetal compartments. Moreover, as maternal FR50 induces fetal overexposure to glucocorticoids and since these hormones are potent regulators of placental glucose transporter expression, we investigated whether putative alterations in placental GLUT expression correlate with changes in maternal and/or fetal corticosterone levels. At term (day 21 of pregnancy), plasma glucose content was significantly reduced (P<0.05) in mothers subjected to FR50, but was not affected in fetuses. Food restriction reduced maternal body weight (P<0.001) but did not affect placental weight. Plasma corticosterone concentration, at term, was increased (P<0.05) in FR50 mothers. Fetuses from FR50 mothers showed reduced body weight (P<0.001) but higher plasma corticosterone levels (P<0.05). Adrenalectomy (ADX) followed by corticosterone supplementation of the mother prevented the FR50-induced rise in maternal plasma corticosterone at term. Food restriction performed on either sham-ADX or ADX mothers induced a similar reduction in the body weight of the pups at term (P<0.01). Moreover, plasma corticosterone levels were increased in pups from sham-ADX FR50 mothers (P<0.01) and in pups from ADX control mothers (P<0.01). Western blot analysis of placental GLUT proteins showed that maternal FR50 decreased placental GLUT3 protein levels in all experimental groups at term (P<0.05 and P<0.01), but did not affect either GLUT1 or GLUT4 protein levels. Northern blot analysis of placental GLUT expression showed that both GLUT1 and GLUT3 mRNA were not affected by the maternal feeding regimen or surgery. We concluded that prolonged maternal malnutrition during late gestation decreases maternal plasma glucose content and placental GLUT3 glucose transporter expression, but does not obviously affect fetal plasma glucose concentration. Moreover, the present results are not compatible with a role of maternal corticosterone in the development of growth-restricted rat fetuses.


Assuntos
Corticosterona/metabolismo , Retardo do Crescimento Fetal/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas do Tecido Nervoso , Distúrbios Nutricionais/metabolismo , Complicações na Gravidez/metabolismo , Prenhez/metabolismo , Animais , Glicemia , Northern Blotting/métodos , Western Blotting/métodos , DNA Complementar/metabolismo , Eletroforese em Gel de Poliacrilamida/métodos , Feminino , Sangue Fetal/química , Transportador de Glucose Tipo 3 , Modelos Biológicos , Tamanho do Órgão , Placenta/anatomia & histologia , Placenta/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Radioimunoensaio/métodos , Ratos , Ratos Wistar
19.
Acta Physiol Scand ; 175(2): 113-21, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12028131

RESUMO

The influence of the two distinct training programmes, moderate (M) and intensive (I), on hypothalamo-pituitary-adrenal (HPA) axis was investigated, in rats. Changes in plasma concentrations of adrenocorticotropin hormone (ACTH) and corticosterone were followed in response to (i) a 60-min acute running session performed on 2nd, 4th and 6th of the seven training weeks (ii) an acute restraint stress of 40 min applied after the final training programme. After 2nd, 4th and 6th week of the two training programmes, a 60-min running resulted in an enhanced secretion of ACTH and corticosterone, compared with both the baseline values (i.e. before running) and to the sedentary (S) group. However, on 4th and 6th weeks compared with 2nd week, ACTH and corticosterone remained elevated in intensive group when they are significantly reduced in moderate group. We could suggest that a moderate training resulted in an adapted hormonal response whereas a deadapted process occurred for the intensive programme. The day after the last training session, basal ACTH, corticosterone and corticosteroid-binding globulin (CBG) capacity were not affected by training. Hypothalamic corticotropin-releasing factor tissue-content (CRF) was increased significantly in the two trained groups. When compared with the sedentary group, the body weight of the rats in the two trained groups was significantly decreased with a total adrenal mass increasing but only in intensive group. The surimposed restraint stress resulted in significant increases in plasma ACTH and corticosterone both in trained and in sedentary animals. This result suggests that the adapted HPA axis response induced by both a moderate and intensive training do not prevent against the effects of a novel stress such as restraint stress.


Assuntos
Sistema Hipotálamo-Hipofisário/fisiologia , Condicionamento Físico Animal/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Glândulas Suprarrenais/crescimento & desenvolvimento , Hormônio Adrenocorticotrópico/sangue , Hormônio Adrenocorticotrópico/metabolismo , Animais , Peso Corporal , Corticosterona/sangue , Corticosterona/metabolismo , Hormônio Liberador da Corticotropina/análise , Sistema Hipotálamo-Hipofisário/química , Sistema Hipotálamo-Hipofisário/metabolismo , Tamanho do Órgão , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Wistar , Estresse Fisiológico/fisiopatologia , Transcortina/análise
20.
J Neuroendocrinol ; 14(2): 135-43, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11849373

RESUMO

In humans, an altered control of cortisol secretion was reported in adult men born with a low birth weight making the hypothalamic-pituitary-adrenal (HPA) axis a possible primary target of early life programming. In rats, we have recently shown that maternal food restriction during late pregnancy induces both an intrauterine growth retardation and an overexposure of fetuses to maternal corticosterone, which disturb the development of the HPA axis in offspring. The first aim of this work was to investigate, in adult male rats, whether perinatal malnutrition has long-lasting effects on the HPA axis activity during both basal and stressful conditions. Moreover, as the HPA axis and sympathetic nervous system are both activated by stress, the second aim of this work was to investigate, in these rats, the adrenomedullary catecholaminergic system under basal and stressful conditions. This study was conducted on 4-month-old male rats malnourished during their perinatal life and on age-matched control animals. Under basal conditions, perinatal malnutrition reduced body weight and plasma corticosteroid-binding globulin (CBG) level but increased mineralocorticoid receptor (MR) gene expression in CA1 hippocampal area. After 30 min of restraint, perinatally malnourished (PM) rats showed increased plasma noradrenaline, adrenocorticotropin hormone (ACTH) and corticosterone concentrations similarly as controls, but calculated plasma-free corticosterone concentration was significantly higher and adrenaline level lower than controls. During the phase of recovery, PM rats showed a rapid return of plasma ACTH and corticosterone concentrations to baseline levels in comparison with controls. These data suggest that in PM rats, an elevation of basal concentrations of corticosterone, in face of reduced CBG and probably increased hippocampal MR lead to a much larger impact of corticosterone on target cells that mediate the negative-feedback mechanism on the activities of both the HPA axis and sympathoadrenal one.


Assuntos
Sistema Hipotálamo-Hipofisário/fisiologia , Distúrbios Nutricionais/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiologia , Estresse Fisiológico/fisiopatologia , Glândulas Suprarrenais/química , Glândulas Suprarrenais/embriologia , Glândulas Suprarrenais/fisiologia , Hormônio Adrenocorticotrópico/sangue , Fatores Etários , Animais , Corticosterona/sangue , Hormônio Liberador da Corticotropina/análise , Hormônio Liberador da Corticotropina/genética , Epinefrina/análise , Epinefrina/sangue , Feminino , Sistema Hipotálamo-Hipofisário/embriologia , Masculino , Eminência Mediana/química , Eminência Mediana/fisiologia , Norepinefrina/análise , Norepinefrina/sangue , Tamanho do Órgão , Núcleo Hipotalâmico Paraventricular/química , Núcleo Hipotalâmico Paraventricular/fisiologia , Sistema Hipófise-Suprarrenal/embriologia , Gravidez , RNA Mensageiro/análise , Ratos , Ratos Wistar , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Restrição Física , Sistema Nervoso Simpático/embriologia , Sistema Nervoso Simpático/fisiologia
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