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1.
Eur Phys J E Soft Matter ; 37(1): 4, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24464137

RESUMO

Heat transfer measurements performed by Riedinger et al. (Phys. Fluids, 25, 015117 (2013)) showed that in an inclined channel, heated from below and cooled from above with adiabatic walls, the flow is laminar or intermittent (local bursts can occur in the laminar flow) when the inclination angle is sufficiently high and the applied power sufficiently low. In this case, gravity plays a crucial role in the characteristics of the flow. In this paper, we present velocity measurements, and their derived tensors, obtained with Particle Image Velocimetry inside the channel. We, also, propose a model derived from a jet interpretation of the flow. Comparison between experiment and model shows a fair agreement.

2.
Pediatr Cardiol ; 34(7): 1695-702, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23609066

RESUMO

An electrophysiologic study (EPS) of children and teenagers with paroxysmal supraventricular tachycardia (SVT) and normal electrocardiography (ECG) in sinus rhythm was evaluated. Generally, EPS is performed only before paroxysmal SVT ablation in these patients. In this study, 140 patients (mean age, 15 ± 3 years) with normal ECG in sinus rhythm were studied for SVT by a transesophageal route in baseline state and after isoproterenol. Idiopathic left or right ventricular tachycardia was diagnosed in four patients (3 %). Anterograde conduction over an atrioventricular (AV) left lateral (n = 10) or septal (n = 9) accessory pathway (AP) was noted in 19 patients (13.5 %) at atrial pacing. Orthodromic AV reentrant tachycardia (AVRT) was induced in these children. Five of the patients had a high rate conducted over AP (>240 bpm in baseline state or >290 bpm after isoproterenol). Two of the patients (a 10-year-old girl with well-tolerated SVT and a 17-year-old with syncope-related SVT) had the criteria for a malignant form with the induction of atrial fibrillation conducted over AP at a rate exceeding 290 bpm in baseline state. Of the 140 patients, 74 (53 %) had typical AV node reentrant tachycardia (AVNRT), nine had atypical AVNRT (6 %), 1 had atrial tachycardia (0.7 %), and 33 (23.5 %) had AVRT related to a concealed AP with only retrograde conduction. Electrophysiologic study is recommended for children with paroxysmal SVT and normal ECG in sinus rhythm. The data are helpful for guiding the treatment. Ventricular tachycardia or atrial tachycardia can be misdiagnosed. Masked preexcitation syndrome with anterograde conduction through AP was present in 13.5 % of the patients, and 1.4 % had a malignant preexcitation syndrome.


Assuntos
Técnicas Eletrofisiológicas Cardíacas/métodos , Taquicardia Supraventricular/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletrocardiografia , Esôfago , Feminino , Seguimentos , Humanos , Masculino , Síndromes de Pré-Excitação , Estudos Retrospectivos , Taquicardia Supraventricular/etiologia , Adulto Jovem
3.
Med Oncol ; 29(3): 1765-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21953054

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common human sarcoma. Most of the data available on GISTs derive from retrospective studies of patients referred to oncology centers. The MolecGIST study sought to determine and correlate clinicopathological and molecular characteristics of GISTs. Tumor samples and clinical records were prospectively obtained and reviewed for patients diagnosed in France during a 24-month period. Five hundred and ninety-six patients were included, of whom 10% had synchronous metastases. GISTs originated from the stomach, small bowel or other site in 56.4, 30.2 and 13.4% of cases, respectively. The main prognostic markers, tumor localization, size and mitotic index were not independent variables (P < 0.0001). Mutational status was determined in 492 (83%) patients, and 138 different mutations were identified. KIT and PDGFRA mutations were detected in 348 (71%) and 74 (15%) patients, respectively, contrasting with 82.8 and 2.1% in patients with advanced GIST (MetaGIST) (P < 0.0001). Further comparison of localized GISTs in the MolecGIST cohort with advanced GISTs from previous clinical trials showed that the mutations of PDGFRA exon18 (D842V and others) as well as KIT exon11 substitutions (W557R and V559D) were more likely to be seen in patients with localized GISTs (odds ratio 7.9, 3.1, 2.7 and 2.5, respectively), while KIT exon 9 502_503dup and KIT exon 11 557_559del were more frequent in metastatic GISTs (odds ratio of 0.3 and 0.5, respectively). These data suggest that KIT and PDGFRA mutations and standardized mitotic count deserve to be investigated to evaluate the relapse risk of GISTs.


Assuntos
Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Mutação , Metástase Neoplásica/genética , Proteínas Proto-Oncogênicas c-kit/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Oncologia/normas , Pessoa de Meia-Idade , Metástase Neoplásica/patologia
4.
Oncogene ; 27(4): 477-89, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17637747

RESUMO

To evaluate the role of murine TFIID subunit TAF4 in activation of cellular genes by all-trans retinoic acid (T-RA), we have characterized the T-RA response of taf4(lox/-) and taf4(-/-) embryonic fibroblasts. T-RA regulates almost 1000 genes in taf4(lox/-) cells, but less than 300 in taf4(-/-) cells showing that TAF4 is required for T-RA regulation of most, but not all cellular genes. We further show that T-RA-treated taf4(lox/-) cells exhibit transforming growth factor (TGF)beta-dependent autocrine growth and identify a set of genes regulated by loss of TAF4 and by T-RA corresponding to key mediators of the TGFbeta signalling pathway. T-RA rapidly and potently induces expression of connective tissue growth factor (CTGF) via a conserved DR2 type response element in its proximal promoter leading to serum-free autocrine growth. These results highlight the role of TAF4 as a cofactor in the cellular response to T-RA and identify the genetic programme of a novel cross talk between the T-RA and TGFbeta pathways that leads to deregulated cell growth.


Assuntos
Comunicação Autócrina/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Tretinoína/farmacologia , Animais , Comunicação Autócrina/genética , Sequência de Bases , Células COS , Células Cultivadas , Chlorocebus aethiops , Fator de Crescimento do Tecido Conjuntivo , Sequência Consenso , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Receptor Cross-Talk/efeitos dos fármacos , Receptores do Ácido Retinoico/metabolismo , Elementos de Resposta , Fator de Transcrição TFIID/genética , Fator de Transcrição TFIID/metabolismo , Fator de Transcrição TFIID/fisiologia , Fator de Crescimento Transformador beta/genética , Receptor gama de Ácido Retinoico
5.
Eur J Pediatr ; 154(2): 130-3, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7720741

RESUMO

UNLABELLED: The Antley-Bixler syndrome is characterized by premature closure of coronal and lambdoidal sutures, proptosis, depression of the nasal bridge, brachycephaly, radio-humeral synostosis and bowing of ulnae and femora associated with fractures. Most cases have been reported after birth with only one case diagnosed prenatally after recurrence of this autosomal recessive syndrome. The two present cases are of interest because of prenatal diagnosis of renal agenesis in the first case and early detection of clinical signs during the second pregnancy. Beside the unusual severity of the renal abnormalities, both cases had an imperforate anus in addition to the more common genital abnormalities. CONCLUSION: Renal agenesis and imperforate anus may occur in the Antley-Bixler syndrome.


Assuntos
Anormalidades Múltiplas , Anus Imperfurado , Osso e Ossos/anormalidades , Rim/anormalidades , Adulto , Face/anormalidades , Feminino , Fêmur/anormalidades , Humanos , Úmero/anormalidades , Masculino , Rádio (Anatomia)/anormalidades , Crânio/anormalidades , Sinostose/complicações , Anormalidades Urogenitais
13.
Reprod Nutr Dev (1980) ; 28 Suppl 1: 65-6, 1988.
Artigo em Francês | MEDLINE | ID: mdl-3254603

RESUMO

The extraction of protein from lucerne produces some liquid residue (called lucerne serum), the effects of which were studied on rumen microbial activity in 6 adult fistulated wethers. The introduction of the serum directly into the rumen stimulated cellulolytic activity whereas its incorporation into the lucerne solid residue before dehydration seemed to have no effect.


Assuntos
Digestão , Medicago sativa , Rúmen/metabolismo , Rúmen/microbiologia , Ovinos/metabolismo , Animais , Masculino
15.
Ann Nutr Aliment ; 34(5-6): 1125-32, 1980.
Artigo em Francês | MEDLINE | ID: mdl-7258912

RESUMO

Although genuine gastro-intestinal allergy is sought as the cause of chronic urticaria or repeated vaso-motor headaches, a non-allergic intolerance of one or more ingested substances, additives to foodstuffs (colourants and conserving agents) are likely to be implicated. Dietary histories from such patients often reveal heavy consumption of charcuterie. Oral provocation tests, performed using additives and placebo, can reproduce symptoms reliably. The substance most frequently incriminated is sodium nitrite (E 250): out of 76 tests, 4 were positive and 4 doubtful. In these cases complete avoidance of E 250 led to significant improvement or cure. We discuss various hypotheses on the harmful effects of sodium nitrite, such as denaturation of histamine-binding SH-group rich mucoproteins, direct toxicity on microvilli or inhibition of intestinal histaminase.


Assuntos
Hipersensibilidade Alimentar/etiologia , Histamina/fisiologia , Nitritos/efeitos adversos , Urticária/induzido quimicamente , Adulto , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Urticária/fisiopatologia
16.
Reprod Nutr Dev (1980) ; 20(5B): 1685-9, 1980.
Artigo em Francês | MEDLINE | ID: mdl-7349503

RESUMO

The cellulolytic activity in the large intestine of the pony varies according to the form and the composition of the feed. This activity was measured on two caecal and ventral colon-cannulated ponies receiving the following 4 diets during four successive 6-week periods: --6 kg of hay, --4 kg of hay + 1 kg of oats, --6 kg of ground, pelleted hay. --5 kg of a ground, pelleted blend of 80 p. 100 hay and 20 p. 100 oats. Adding oats to a hay feed increased the cellulolytical activity in the caecum and the colon, whereas grinding and pelleting hay alone or hay enriched with oats diminished that activity in the caecum without modifying it in the colon (table 1). The volatile fatty acid production shown in table 2 does not always vary in the same way as cellulolytic activity; this might be due to some variations in the values of the digestive contents in the two compartments.


Assuntos
Ração Animal , Celulose/metabolismo , Cavalos/metabolismo , Intestino Grosso/metabolismo , Animais , Ceco/metabolismo , Colo/metabolismo , Grão Comestível , Ácidos Graxos Voláteis/metabolismo , Masculino
17.
Reprod Nutr Dev (1980) ; 20(5B): 1691-4, 1980.
Artigo em Francês | MEDLINE | ID: mdl-7349504

RESUMO

We studied a caecum-cannulated pony fed hay libitum in order to determine the mineral elements likely to cause deficiencies which decrease microbial activity in the caecum. During four successive 1-month periods, we observed the effects of adding 50 mg of iron, 1 mg of cobalt, 40 mg of copper and 200 mg of zinc, respectively. Except for the introduction of zinc, which greatly diminishes cellulolytic activity measured with the nylon bag technique, there was no significant modification in that activity as shown by pH, NH3-nitrogen, total nitrogen and volatile fatty acid production (table 1). It can be concluded that endogenous secretion in the pre-caecal part of the digestive system of the mineral elements used was sufficient to guarantee good symbiosis between the microbial population of the caecum and the organism.


Assuntos
Ceco/metabolismo , Celulose/metabolismo , Cavalos/metabolismo , Oligoelementos/farmacologia , Animais , Ceco/efeitos dos fármacos , Ceco/microbiologia , Cobalto/farmacologia , Cobre/farmacologia , Ácidos Graxos Voláteis/metabolismo , Ferro/farmacologia , Masculino , Oligoelementos/administração & dosagem , Zinco/farmacologia
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