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1.
Encephale ; 44(2): 148-151, 2018 Apr.
Artigo em Francês | MEDLINE | ID: mdl-27745718

RESUMO

OBJECTIVE: The 20-item Toronto Alexithymia Scale (TAS-20) is the most widely used measure of alexithymia in non-clinical or clinical populations. The TAS-20 evaluates three dimensions of the alexithymia construct: the difficulty identifying feelings (DIF), the difficulty describing feelings (DDF) and externally oriented thinking (EOT). The TAS-20 is also used in adolescents or children, and the psychometric properties of the scale have not been systematically evaluated in these populations. Recently several studies have shown systematic age differences in the factor structure and a decrease of the quality of the measurement with age. Notably, low reliability measured by the Cronbach α coefficient has been found for the EOT factor. Taking into account the limitations of the TAS-20 in pre-adult populations the Alexithymia Questionnaire for Children (AQC), an adaptation of the TAS-20, has been proposed by a reformulation of the TAS-20 items (Rieffe et al., 2006). Two studies in healthy children found satisfactory psychometric properties with the three-factor structure demonstrating adequate parameters in the confirmatory factorial analyses (CFA). In the two studies low reliabilities of the EOT factor were reported, and recent studies in adolescents using the TAS-20 found that a two-factor model (DDF, DIF) had a better fit than the original three-factor model. Thus, the aim of the present study was firstly to verify the psychometric properties of the AQC in a sample of adolescents presenting various psychiatric disorders and secondly to test the adequacy of the bi- or tridimensional model of the scale. METHOD: One hundred and five adolescents (27 males, 78 females) with a mean age of 15.06 years (sd=1.55, range: 12-18 years) were hospitalized in the adolescent psychiatric department of the Erasme Hospital (Bruxelles, Belgium) for various psychiatric disorders. The main diagnoses were: adjustment disorder (n=56, 53.5%), mood or anxiety disorders (n=17, 16.2%), impulse control disorder (n=11, 10.5%). The subjects completed the French version of the AQC. CFA were done testing the adequacy of the three or two-factor structure of the scale. Two indices were considered: the normed χ2 (ratio of χ2 and degrees of freedom) and the root mean square error of approximation (RMSEA). The values for acceptable fit were normed χ2<3 and RMSEA<0.05. Cronbach α were also calculated. RESULTS: Fit indices for the three-factor model were respectively 1.165 and 0.0303 for the normed χ2 and RMSEA. For the two-factor model, the values were respectively 0.819 and 0. Thus, these two well-fitting models were compared using the χ2-difference test, which indicated a significantly better fit for the two-factor model over the three-factor model (χ2-difference=151.447, delta df=114, P<0.05). The values of the Cronbach α coefficients were respectively 0.72, 0.75, 0.18 for DIF, DDF and EOT subscales. Moreover, the values of the Cronbach α coefficients were respectively 0.71 and 0.83 for the full scale and the scale without the EOT items. CONCLUSION: The Alexithymia Questionnaire for Children had satisfactory psychometric properties found in a sample of adolescent psychiatric inpatients. Taking into account firstly the superiority of the two-factor model over the classical three-factor model and secondly the low value of the Cronbach α for the EOT factor, it is proposed to use only the twelve-item scale by excluding the EOT items.


Assuntos
Sintomas Afetivos/diagnóstico , Sintomas Afetivos/psicologia , Psicometria , Inquéritos e Questionários , Adolescente , Psiquiatria do Adolescente , Criança , Análise Fatorial , Feminino , Hospitais Psiquiátricos , Humanos , Pacientes Internados , Masculino , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes
2.
Pancreatology ; 17(4): 572-579, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28600220

RESUMO

BACKGROUND/OBJECTIVES: The epidemiology, natural history, complications, and therapeutic management of chronic pancreatitis (CP) are not well described at the national level. This multi-centre prospective observational study involving eight Belgian hospitals aimed to improve the understanding of these aspects of CP in Belgium. METHODS: All patients with a diagnosis of CP based on imaging were eligible for this study. Data were gathered regarding epidemiology, etiology, CP complications, and treatment modalities. RESULTS: A total of 809 patients were included between 1/9/2014 and 31/8/2015. Most patients (794) were adults ≥16-years old, 74% were male, the median age at symptom onset was 47 (38-57) years, the median disease duration was 7 (3-13) years, and the median Izbicki pain score (IPS) was 96 (0-195). The main etiological risk factors according to the TIGAR-O classification were alcohol and tobacco (67%). Current drinkers had lower body mass index (BMI) (21.4 kg/m2 vs 24.1 kg/m2), higher IPS (110 vs 56), and longer inability to work than non-drinkers. Current smokers had lower BMI (21.5 kg/m2 vs 25 kg/m2) and higher IPS (120 vs 30) than non-smokers. Endocrine insufficiency and/or clinical steatorrhea was recorded in 41% and 36% of patients, respectively. The highest IPS was reported in patients with ongoing endotherapy (166 vs 50 for patients who completed endoscopy). CONCLUSION: This multicentric study on CP patients showed that current alcohol drinking and smoking are associated with pain and malnutrition. Pain scores were higher in patients with ongoing endotherapy, independently of surgery.

3.
Gut ; 65(2): 305-12, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26045140

RESUMO

OBJECTIVES: Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality. DESIGN: Retrospective multinational study including SCN diagnosed between 1990 and 2014. RESULTS: 2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1). CONCLUSIONS: After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN. TRIAL REGISTRATION NUMBER: IRB 00006477.


Assuntos
Cistadenoma Seroso , Neoplasias Pancreáticas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistadenoma Seroso/diagnóstico , Cistadenoma Seroso/mortalidade , Cistadenoma Seroso/patologia , Cistadenoma Seroso/terapia , Europa (Continente) , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Estudos Retrospectivos , Sociedades Médicas , Adulto Jovem
4.
Rev Med Brux ; 37(4): 294-301, 2016.
Artigo em Francês | MEDLINE | ID: mdl-28525229

RESUMO

Pancreatitis are inflammatory diseases of the pancreas and include acute pancreatitis (AP) and chronic pancreatitis (CP). The diagnosis of AP is based on the fulfillment of 2 out of 3 criteria : abdominal pain, hyperlipasemia, signs of AP on imaging. The most frequent etiologies of AP are gallstone(s) and alcohol abuse. The early management of AP includes in all cases, fluid resuscitation, pain control and transient fasting. In biliary AP, endoscopic biliary sphincterotomy should be performed only if associated cholangitis. In infected organized necrosis with clinical deterioration despite conservative treatment, an invasive treatment (step-upapproach by drainage ± necrosectomy) could be proposed. Contrary to AP, the morphological alterations of the pancreatic ducts and parenchyma are irreversible in CP. The clinical presentation of CP is dominated by abdominal pain associated with loss of weight and denutrition. The mechanisms of pain generation in CP are multiple and complex. Endoscopic therapy could be proposed with the aim to relieve a distal ductal obstruction and could provide clinical improvement in about 2/3 of patients. Surgery, either by pancreaticojejunostomy or resection remains indicated for 20 - 25 % of patients. The management of complications from CP (biliary stricture, pseudocyst) is also important as well as the treatment of diabetes and steatorrhea in order to avoid denutrition.


Les pancréatites sont des affections inflammatoires du pancréas et comprennent les pancréatites aiguës (PA) et les pancréatites chroniques (PC). Le diagnostic de PA se base sur la présence d'au moins 2 parmi 3 critères : douleur abdominale, élévation de la lipasémie, signes de PA à l'imagerie. Les causes les plus fréquentes de PA sont la lithiase biliaire et l'alcoolisme. La prise en charge précoce d'une PA comprend dans tous les cas une (hyper) hydratation, un contrôle de la douleur et une mise à jeun transitoire du patient. En cas de PA d'étiologie biliaire, une sphinctérotomie biliaire ne doit être réalisée en urgence qu'en cas d'angiocholite associée. En cas de nécrose liquéfiée, surinfectée, associée à une détérioration clinique du patient, malgré un traitement conservateur, un traitement invasif (drainage ± nécrosectomie) peut être proposé. Contrairement à la PA, les altérations morphologiques (au niveau des canaux et du parenchyme pancréatiques) sont irréversibles dans la PC. La symptomatologie clinique de la PC est dominée par la douleur associée à l'amaigrissement et la dénutrition. Les mécanismes de la douleur sont multiples dans la PC. En cas d'obstacle canalaire distal, un traitement endoscopique visant à drainer le canal pancréatique principal permet d'obtenir une amélioration clinique pour environ 2/3 des patients. La chirurgie, soit de dérivation pancréaticojéjunale, soit de résection reste indiquée pour 20 à 25 % des patients. La prise en charge des complications de la PC (sténose biliaire, pseudokyste) est aussi importante ainsi que le contrôle du diabète et de la stéatorrhée.


Assuntos
Pancreatite/diagnóstico , Pancreatite/terapia , Doença Aguda , Humanos , Pancreatite Crônica/diagnóstico , Pancreatite Crônica/terapia
5.
Rev Med Brux ; 36(3): 152-7, 2015.
Artigo em Francês | MEDLINE | ID: mdl-26372976

RESUMO

The Munchausen syndrome by proxy (MSBP) was first described in 1977 by the English paediatrician Roy Meadow. The MSBP is an extremely complicated diagnosis because of the difficulty in finding the incriminating evidence of its existence and because of the ethical issue it raises for caregivers. Its implications from a medical, psychological and legal point of view raise difficult questions for any professional confronted to it. In this article we will first present the case of a 16-year-old teenager who had been bedridden in hospital for a year, before an atypical form of MSBP was finally diagnosed, after a stay in a child and adolescent psychiatry unit. We will then discuss this case in light of a literature review on the MSBP.


Assuntos
Síndrome de Munchausen Causada por Terceiro/diagnóstico , Adolescente , Adulto , Maus-Tratos Infantis/diagnóstico , Maus-Tratos Infantis/reabilitação , Feminino , Humanos , Masculino , Comportamento Materno/psicologia , Síndrome de Munchausen Causada por Terceiro/terapia
6.
Rev Med Brux ; 36(5): 415-20, 2015.
Artigo em Francês | MEDLINE | ID: mdl-26749631

RESUMO

Loneliness is particularly prevalent during adolescence, a time also associated with the appearance of psychiatric illnesses. Loneliness has been linked to a number of mental health indicators such as depressive symptoms, self-esteem, anxiety, and perceived stress. During adolescence, the individual undergoes major social and personal transformations through redefining their social network thus making them more susceptible to developing mental health problems. Some studies suggest that the risk of mental health problems arises when an adolescent is repeatedly faced with loneliness. Mental health workers should therefore focus on any given adolescent's inability to establish satisfactory interpersonal relationships as a predictive element of loneliness. Thus, it would seem that the development of loneliness prevention and intervention programs aimed at adolescents who are unable to establish satisfactory interpersonal relationships could be of benefit to many.


Assuntos
Solidão/psicologia , Adolescente , Ansiedade/psicologia , Depressão/psicologia , Humanos , Personalidade , Autoimagem , Estresse Psicológico/psicologia
7.
Endoscopy ; 44(8): 784-800, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22752888

RESUMO

BACKGROUND AND AIMS: Clarification of the position of the European Society of Gastrointestinal Endoscopy (ESGE) regarding the interventional options available for treating patients with chronic pancreatitis. METHODS: Systematic literature search to answer explicit key questions with levels of evidence serving to determine recommendation grades. The ESGE funded development of the Guideline. SUMMARY OF SELECTED RECOMMENDATIONS: For treating painful uncomplicated chronic pancreatitis, the ESGE recommends extracorporeal shockwave lithotripsy/endoscopic retrograde cholangiopancreatography as the first-line interventional option. The clinical response should be evaluated at 6 - 8 weeks; if it appears unsatisfactory, the patient's case should be discussed again in a multidisciplinary team. Surgical options should be considered, in particular in patients with a predicted poor outcome following endoscopic therapy (Recommendation grade B). For treating chronic pancreatitis associated with radiopaque stones ≥ 5 mm that obstruct the main pancreatic duct, the ESGE recommends extracorporeal shockwave lithotripsy as a first step, combined or not with endoscopic extraction of stone fragments depending on the expertise of the center (Recommendation grade B). For treating chronic pancreatitis associated with a dominant stricture of the main pancreatic duct, the ESGE recommends inserting a single 10-Fr plastic stent, with stent exchange planned within 1 year (Recommendation grade C). In patients with ductal strictures persisting after 12 months of single plastic stenting, the ESGE recommends that available options (e. g., endoscopic placement of multiple pancreatic stents, surgery) be discussed in a multidisciplinary team (Recommendation grade D).For treating uncomplicated chronic pancreatic pseudocysts that are within endoscopic reach, the ESGE recommends endoscopic drainage as a first-line therapy (Recommendation grade A).For treating chronic pancreatitis-related biliary strictures, the choice between endoscopic and surgical therapy should rely on local expertise, patient co-morbidities and expected patient compliance with repeat endoscopic procedures (Recommendation grade D). If endoscopy is elected, the ESGE recommends temporary placement of multiple, side-by-side, plastic biliary stents (Recommendation grade A).


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Colangiopancreatografia Retrógrada Endoscópica/normas , Gastroenterologia , Pancreatite Crônica/cirurgia , Guias de Prática Clínica como Assunto , Sociedades Médicas , Europa (Continente) , Humanos
8.
Rev Med Brux ; 31(4): 221-5, 2010 Sep.
Artigo em Francês | MEDLINE | ID: mdl-21089394

RESUMO

The diagnosis of schizophrenia at adolescence is still difficult. The premorbid history and past family history can help with the differential diagnosis in this situation. Studies on the future of schizophrenic adolescents show that the disorder has particularly harmful consequences on the individuals' development and psychosocial adaptation. The risk of suicide is present. Comorbid disorders as cannabis abuse are discussed. Paradoxically, there are only few data about a productive therapy. The efficacy of prevention remains to be shown.


Assuntos
Esquizofrenia , Adolescente , Humanos , Esquizofrenia/diagnóstico , Esquizofrenia/terapia
9.
World J Gastroenterol ; 14(7): 1027-33, 2008 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-18286683

RESUMO

Acute recurrent pancreatitis is a clinical entity largely associated with pancreatic ductal obstruction. This latter includes congenital variants, of which pancreas divisum is the most frequent but also controversial, chronic pancreatitis, tumors of the pancreaticobiliary junction and sphincter of Oddi dysfunction. This review summarizes current knowledge about diagnostic work-up and therapy of these conditions.


Assuntos
Ductos Pancreáticos/patologia , Pancreatite/etiologia , Constrição Patológica , Humanos , Pâncreas/anormalidades , Ductos Pancreáticos/anormalidades , Ductos Pancreáticos/fisiopatologia , Neoplasias Pancreáticas/complicações , Pancreatite/patologia , Pancreatite/fisiopatologia , Pancreatite Crônica/complicações , Recidiva , Disfunção do Esfíncter da Ampola Hepatopancreática/complicações , Disfunção do Esfíncter da Ampola Hepatopancreática/fisiopatologia
11.
Acta Gastroenterol Belg ; 79(2): 257-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27382949

RESUMO

Atypical haemolytic uraemic syndrome (aHUS) is a rare but life-threatening complement system-related disorder, characterized by renal failure, non-immune haemolytic anaemia and thrombo-cytopenia. We report on a young woman who developed a pancreatitis-induced aHUS following a routine procedure of endoscopic retrograde cholangiopancreatography. The patient was successively treated by 2 plasma exchanges with fresh frozen plasma and eculizumab, a monoclonal antibody designed to block terminal complement activation. The last treatment resulted in the immediate improvement of haemolytic parameters and to the definitive suspension of plasma exchanges. This is likely the first description of the use of a complement inhibitor to treat post-pancreatitis aHUS. We discussed treatment options and concluded that eculizumab could be a beneficial alternative to plasma exchanges in the management of such complications.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Síndrome Hemolítico-Urêmica Atípica/terapia , Inativadores do Complemento/uso terapêutico , Troca Plasmática , Síndrome Hemolítico-Urêmica Atípica/etiologia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Feminino , Humanos , Pancreatite/complicações , Pancreatite/terapia , Adulto Jovem
12.
Scand J Surg ; 94(2): 143-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16111097

RESUMO

When endoscopic therapy is used for the treatment of patients with painful chronic pancreatitis, extracorporeal shock wave lithotripsy (ESWL) can be proposed as a first-line approach when obstructive ductal stone(s) induce upstream dilation of the main pancreatic duct. Stone fragmentation by ESWL is followed by endoscopic ductal drainage using pancreatic sphincterotomy, fragmented stone(s) extraction, and pancreatic stenting in case of ductal stricture. After completion of endoscopic pancreatic ductal drainage, long-term clinical benefit can be expected for two thirds of the patients. Best clinical results are associated with absence or cessation of smoking and with early treatment in the course of chronic pancreatitis, while alcohol abuse increases the risks of diabetes, steatorrhea and mortality. The complications of chronic pancreatitis are mainly the development of pseudocyst secondary to the downstream ductal obstruction, and biliary obstruction caused by fibrotic changes in the head of the pancreas. Successful endoscopic pseudocyst drainage is currently obtained in most patients, and carries a low complication rate. Biliary stenting is a safe and effective technique for the short-term treatment of symptomatic bile duct stricture due to chronic pancreatitis, but permanent resolution is obtained in only 25% of cases. In conclusion, endoscopic management is now considered to be the preferred interventional treatment of chronic pancreatitis, for patients selected on the basis of the anatomical changes caused by the disease. This treatment is generally safe, minimally invasive, often effective for years, does not prevent further surgery, and can be repeated.


Assuntos
Pancreatite/terapia , Esfinterotomia Endoscópica , Doença Crônica , Descompressão Cirúrgica/métodos , Dilatação , Drenagem , Humanos , Litotripsia , Ductos Pancreáticos , Pseudocisto Pancreático/cirurgia , Pancreatite/complicações , Stents
13.
Orthop Traumatol Surg Res ; 101(6 Suppl): S241-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26372185

RESUMO

INTRODUCTION: Interbody fusion is the gold standard treatment for the management of numerous diseases of the spine. Minimally invasive techniques may be more beneficial than conventional techniques. The main goal of this study was to report the one-year postoperative results of a series of posterior lumbar interbody fusions by a minimally invasive technique in relation to improvement in functional outcome, interbody fusion and morbidity. MATERIALS AND METHODS: Between January 2012 and May 2013, 182 patients treated by minimally invasive posterior transforaminal lumbar interbody fusion (TLIF) were included in this prospective multicenter study. Clinical assessment was based on a comparison of the preoperative and one-year postoperative Oswestry (ODI), SF-12 and Quebec Scores and the Visual Analog Scale (VAS). Surgical and postoperative follow-up data were evaluated. Radiological assessment was based preoperative and one-year postoperative full spine teleradiographs. Interbody fusion at one-year was systematically evaluated by CT scan. RESULTS: One hundred and eighty-two patients were included, mean age 58.9 years old. Surgery lasted a mean 101 minutes, mean preoperative bleeding was 143 mL, and mean radiation exposure was 247.4 cGy/cm(2). The rate of postoperative complications was 7.7%. The ODI, the Quebec Score, the SF-12 and the VAS were all significantly improved at one-year (P<0.0001). The rate of fusion was 72.6% at the final follow-up. There was no significant difference in functional outcome between patients with and without fusion. DISCUSSION: The one-year postoperative radiological results and functional outcome of minimally invasive posterior lumbar fusion are satisfactory. The benefits of this minimally invasive approach are mainly found in the first 6 postoperative months. Successful radiological interbody fusion was not correlated to functional outcome at the final follow-up.


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações Pós-Operatórias/epidemiologia , Fusão Vertebral/métodos , Adulto , Feminino , França/epidemiologia , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
14.
Mech Ageing Dev ; 28(2-3): 337-41, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6521514

RESUMO

The in vitro effect of triiodothyronine (T3) 10(-5) M upon lipolysis was studied on white fat cells isolated from 1.5-6- and 30-month-old rats. We couldn't see any consistent effect of this hormone upon the basal lipolysis. We observed a T3 effect on epinephrine-stimulated lipolysis on the three groups of animals. After 1 h of incubation the increase of glycerol release varies with the dose of epinephrine; after 3 h the T3 effect persisted only in the 6-month and 30-month groups.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Envelhecimento , Lipólise/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Tecido Adiposo/metabolismo , Animais , Epinefrina/farmacologia , Glicerol/metabolismo , Técnicas In Vitro , Masculino , Ratos , Ratos Endogâmicos
15.
Biochimie ; 57(4): 401-15, 1975.
Artigo em Francês | MEDLINE | ID: mdl-1148331

RESUMO

The frequency shift observed when light is scattered by molecules is called Raman effect. Raman spectroscopy like infrared spectroscopy is a method of studying molecular vibrations. The two methods are complementary, they both give much informations about the structure of molecules and crystals, the nature of chemical bonds and intermolecular interactions. Infrared absorption is allowed if the vibration is accompanied by a variation of electric dipole moment, however Raman scattering will only be observed if a variation of molecular polarizability appears during the vibration. Symetry properties of molecules of crystals lead to the determination of the number of normal vibrational modes and their Raman or infrared activity. The discovery of Laser light source has permitted a great development of Raman instrumentation. Raman spectrometers can easily record the whole spectrum of molecular vibrations (0-4000 cm-1) of samples in solid, liquid or gazeous state. Very small quantities of material are required (several milligrams). Aqueous solutions are easily investigated. Owing to the easy exploration of the low frequency range by modern spectrometers, new areas are opened in the study of the solid state and polymeric chains. Resonance Raman effect allows the spectra of very dilute solutions to be obtained. With the development of rapid scanning systems and electro-optical spectrometers, study of transients species is now possible. Among the physical analysis methods, Raman spectroscopy is now more and more used, and this technic has already been successfully used in numerous biological and biochemical problems.


Assuntos
Espalhamento de Radiação , Análise Espectral/métodos , Cristalografia , Lasers , Luz , Modelos Químicos , Conformação Molecular , Polarografia , Polímeros/análise , Soluções , Análise Espectral/instrumentação , Fatores de Tempo , Vibração
16.
Biochem Pharmacol ; 34(7): 1057-63, 1985 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2580534

RESUMO

To evaluate the modulation of pancreatic muscarinic receptors in two states of pancreatic growth, hypertrophy and hyperplasia, caerulein, a cholecystokinin analog, (1 microgram/kg) was administered thrice daily for 2 and 4 days to adult rats. After 2 days of treatment, pancreatic hypertrophy was well established as evidenced by increases in pancreatic weight, cellular mass and protein content. Using an increase in DNA content as an index of hyperplasia, we demonstrated that pancreatic hyperplasia occurred only after 4 days of caerulein treatment. Caerulein increased the concentration of muscarinic receptors per DNA in pancreatic homogenate by 57% over control value after 2 days of treatment without modification of the receptor affinity for the ligand QNB. This increase involved mainly receptors in the low affinity state for carbamylcholine and their concentration returned to control levels after 4 days of treatment. The functional capacity of the acini was significantly increased after 2 days of caerulein as amylase release (U/mg DNA) was significantly increased but the sensitivity of these acini to carbamylcholine was significantly decreased. After 4 days of caerulein, the functional capacity has returned towards control values but the sensitivity to carbamylcholine remained decreased. The increase in muscarinic receptor concentration could be ascribed to a general increase in cellular proteins, as part of the hypertrophic effect of caerulein. This specific effect would also explain the increased functional secretory capacity of the caerulein-treated acini but the decreased sensitivity to carbamylcholine probably resulted in changes at a postreceptor loci since the affinities of the muscarinic receptors for carbamylcholine remained unaffected.


Assuntos
Ceruletídeo/farmacologia , Pâncreas/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Amilases/metabolismo , Animais , Ligação Competitiva , Colecistocinina/farmacologia , DNA/análise , Masculino , Tamanho do Órgão/efeitos dos fármacos , Proteínas/análise , Ratos , Ratos Endogâmicos
17.
Biochem Pharmacol ; 32(12): 1831-5, 1983 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-6136280

RESUMO

The beta-adrenergic stimulation of adenylate cyclase in membranes from human lung was compared to that of adenylate cyclase in membranes with a majority of beta 2-adrenergic receptors (from rat lung) and in membranes with a homogeneous population of beta 2-adrenergic receptors (from rat erythrocytes and reticulocytes). In terms of adenylate cyclase stimulation, three full agonists (isoproterenol, epinephrine and norepinephrine), four partial agonists (procaterol, salbutamol, fenoterol and zinterol), and four antagonists (propranolol, metoprolol, atenolol and practolol) were tested. The potency (Kact or Ki) of the eleven beta-adrenergic agents, and the Hill coefficient (of 1) for the four antagonists tested indicated that the activation of human lung adenylate cyclase occurred through receptors of the beta 2-subtype only. Partial beta-adrenergic agonists were efficiently discriminated by the human lung preparation, as shown by distinct intrinsic activities. The mediocre efficacy and the relatively low potency of all beta-adrenergic agonists on adenylate cyclase suggested a relatively low density of beta 2-adrenergic receptors, as compared to the enzyme density.


Assuntos
Adenilil Ciclases/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Pulmão/efeitos dos fármacos , Inibidores de Adenilil Ciclases , Animais , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/enzimologia , Humanos , Técnicas In Vitro , Pulmão/enzimologia , Ratos , Ratos Endogâmicos , Reticulócitos/efeitos dos fármacos , Reticulócitos/enzimologia
18.
Int J Oncol ; 3(5): 1005-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21573466

RESUMO

Using two-dimensional Western blot analysis with a pan-ras antibody, we previously defined conditions that allow to resolve the four post-translational p21-H-ras products expressed in normal mature rat tissues. Using the same approach, we conducted experiments that sometimes revealed deviations from the normal basal p21-H-ras pattern in primary human liver tumors. One type of alteration encountered was indicative of modifications in the relative rate of accomplishment of the different steps in the post-translational metabolisation of the protein, resulting in the accumulation of precursors of the fully-processed p21-H-ras product. This was also observed during ontogenesis and might thus be correlated with either cellular growth potential or differentiation. The second type of altered pattern is defined by the detection of abnormal spots and probably corresponds to the presence of mutant p21-ras products.

19.
Peptides ; 2 Suppl 2: 253-8, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6123988

RESUMO

The binding of 125I-VIP (Vasoactive Intestinal Peptide) to a crude particulate fraction from a rat lung was reversible and 125-I-VIP dissociation was accelerated by guanine triphosphate nucleotides. The relative potency of VIP and related peptides to compete with 125-VIP for binding was similar to their ability to stimulate adenylate cyclase in the same preparation. Dose-effect curves were compatible with the existence of two classes of VIP-receptors: a high-affinity type with equal affinity for VIP and [Val5] secretin, and a low-affinity type with affinity decreasing in the order VIP greater than [Val5] secretin greater than secretin. The response of a crude particulate adenylate cyclase preparation from human lung was also investigated. The biphasic pattern of adenylate cyclase stimulation by VIP suggested the presence of high- and low-affinity VIP receptors coupled to the enzyme. In addition, the stimulation of adenylate cyclase by secretin and [Val5] secretin was also biphasic, suggesting the coexistence of high- and low-affinity secretin receptors, Secretin (7-27) inhibited completely the secretin-stimulated activity operating through high-affinity secretion receptors, so that these receptors appear to be genuine secretin-preferring receptors.


Assuntos
Pulmão/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores dos Hormônios Gastrointestinais , Adenilil Ciclases/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Adulto , Animais , Ligação Competitiva , Ativação Enzimática/efeitos dos fármacos , Guanosina Trifosfato/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Prostaglandinas/farmacologia , Ratos , Receptores Acoplados a Proteínas G , Receptores de Peptídeo Intestinal Vasoativo , Secretina/farmacologia , Peptídeo Intestinal Vasoativo/metabolismo , Peptídeo Intestinal Vasoativo/farmacologia
20.
Peptides ; 3(6): 897-900, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6897744

RESUMO

The presence of receptors, recognized by Vasoactive Intestinal Peptide (VIP) and Peptide having N-terminal Histidine and C-terminal Isoleucine amide (PHI), was documented in membranes from human right auricle and left ventricular cardiac muscle by the ability of these peptides to stimulate adenylate cyclase. The capacity of VIP and PHI to activate the enzyme was comparable, in auricle as well as ventricle membranes, the affinity of the system being moderately higher for VIP than for PHI. In auricles, dose-effect curves appeared compatible with the coexistence of high-affinity and low-affinity VIP receptors. PHI could not, however, discriminate these subclasses of VIP receptors.


Assuntos
Adenilil Ciclases/metabolismo , Hormônios Gastrointestinais/farmacologia , Miocárdio/enzimologia , Peptídeos/farmacologia , Peptídeo Intestinal Vasoativo/farmacologia , Glucagon/farmacologia , Humanos , Técnicas In Vitro , Isoproterenol/farmacologia , Membranas/enzimologia , Peptídeo PHI , Estimulação Química
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