928 resultados para Inhibiteurs de phosphodiestérase de type 5
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The object of this study was to evaluate the contribution of carotid distensibilty on baroreflex sensitivity in patients with type 2 diabetes mellitus with at least 2 additional cardiovascular risk factors. Carotid distensibility was measured bilaterally at the common carotid artery in 79 consecutive diabetic patients and 60 matched subjects without diabetes. Spontaneous baroreflex sensitivity assessment was obtained using time and frequency methods. Baroreflex sensitivity was lower in diabetic subjects as compared with nondiabetic control subjects (5.25+/-2.80 ms/mm Hg versus 7.55+/-3.79 ms/mm Hg; P<0.01, respectively). Contrary to nondiabetic subjects, diabetic subjects showed no significant correlation between carotid distensibility and baroreflex sensitivity (r2=0.08, P=0.04 and r2=0.04, P=0.13, respectively). In diabetic subjects, baroreflex sensitivity was significantly lower in subjects with peripheral neuropathy than in those with preserved vibration sensation (4.1+/-0.5 versus 6.1+/-0.4 ms/mm Hg, respectively; P=0.005). Age in nondiabetic subjects, diabetes duration, systolic blood pressure, peripheral or sensitive neuropathy, and carotid distensibility were introduced in a stepwise multivariate analysis to identify the determinants of baroreflex sensitivity. In diabetic patients, neuropathy is a more sensitive determinant of baroreflex sensitivity than the reduced carotid distensibility (stepwise analysis; F ratio=5.1, P=0.028 versus F ratio=1.9, P=0.16, respectively). In diabetic subjects with 2 additional cardiovascular risk factors, spontaneous baroreflex sensitivity is not related to carotid distensibility. Diabetic subjects represent a particular population within the spectrum of cardiovascular risk situations because of the marked neuropathy associated with their metabolic disorder. Therefore, neuropathy is a more significant determinant of baroreflex sensitivity than carotid artery elasticity in patients with type 2 diabetes.
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BACKGROUND: Both nutritional and genetic factors are involved in the pathogenesis of nonalcoholic fatty liver disease and insulin resistance. OBJECTIVE: The aim was to assess the effects of fructose, a potent stimulator of hepatic de novo lipogenesis, on intrahepatocellular lipids (IHCLs) and insulin sensitivity in healthy offspring of patients with type 2 diabetes (OffT2D)--a subgroup of individuals prone to metabolic disorders. DESIGN: Sixteen male OffT2D and 8 control subjects were studied in a crossover design after either a 7-d isocaloric diet or a hypercaloric high-fructose diet (3.5 g x kg FFM(-1) x d(-1), +35% energy intake). Hepatic and whole-body insulin sensitivity were assessed with a 2-step hyperinsulinemic euglycemic clamp (0.3 and 1.0 mU x kg(-1) x min(-1)), together with 6,6-[2H2]glucose. IHCLs and intramyocellular lipids (IMCLs) were measured by 1H-magnetic resonance spectroscopy. RESULTS: The OffT2D group had significantly (P < 0.05) higher IHCLs (+94%), total triacylglycerols (+35%), and lower whole-body insulin sensitivity (-27%) than did the control group. The high-fructose diet significantly increased IHCLs (control: +76%; OffT2D: +79%), IMCLs (control: +47%; OffT2D: +24%), VLDL-triacylglycerols (control: +51%; OffT2D: +110%), and fasting hepatic glucose output (control: +4%; OffT2D: +5%). Furthermore, the effects of fructose on VLDL-triacylglycerols were higher in the OffT2D group (group x diet interaction: P < 0.05). CONCLUSIONS: A 7-d high-fructose diet increased ectopic lipid deposition in liver and muscle and fasting VLDL-triacylglycerols and decreased hepatic insulin sensitivity. Fructose-induced alterations in VLDL-triacylglycerols appeared to be of greater magnitude in the OffT2D group, which suggests that these individuals may be more prone to developing dyslipidemia when challenged by high fructose intakes. This trial was registered at clinicaltrials.gov as NCT00523562.
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While the morphological and electrophysiological changes underlying diabetic peripheral neuropathy (DPN) are relatively well described, the involved molecular mechanisms remain poorly understood. In this study, we investigated whether phenotypic changes associated with early DPN are correlated with transcriptional alterations in the neuronal (dorsal root ganglia [DRG]) or the glial (endoneurium) compartments of the peripheral nerve. We used Ins2(Akita/+) mice to study transcriptional changes underlying the onset of DPN in type 1 diabetes mellitus (DM). Weight, blood glucose and motor nerve conduction velocity (MNCV) were measured in Ins2(Akita/+) and control mice during the first three months of life in order to determine the onset of DPN. Based on this phenotypic characterization, we performed gene expression profiling using sciatic nerve endoneurium and DRG isolated from pre-symptomatic and early symptomatic Ins2(Akita/+) mice and sex-matched littermate controls. Our phenotypic analysis of Ins2(Akita/+) mice revealed that DPN, as measured by reduced MNCV, is detectable in affected animals already one week after the onset of hyperglycemia. Surprisingly, the onset of DPN was not associated with any major persistent changes in gene expression profiles in either sciatic nerve endoneurium or DRG. Our data thus demonstrated that the transcriptional programs in both endoneurial and neuronal compartments of the peripheral nerve are relatively resistant to the onset of hyperglycemia and hypoinsulinemia suggesting that either minor transcriptional alterations or changes on the proteomic level are responsible for the functional deficits associated with the onset of DPN in type 1 DM.
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RESUME Objectifs. Évaluer la prévalence de maladie coronarienne chez les patients diabétiques de type 2 asymptomatiques ou avec angor atypique selon les recommandations américaines de l'American Diabetes Association et de l'American College of Cardiology. Méthodes. Cent cinquante-quatre patients diabétiques de type 2 asymptomatiques ou avec angor atypique et présentant au minimum 2 facteurs de risque cardio-vasculaires additionnels ont été dépistés par échocardiographie de stress (71%, n=109), scintigraphie myocardique de perfusion (26%, n=40) ou l'association des 2 examens (3%, n=5). Résultats. L'échocardiographie de stress s'est révélée positive chez 16 patients (14%) et 14 ont eu une coronarographie révélant des sténoses significatives chez 12 (86%). La scintigraphie myocardique de perfusion était positive chez 16 patients (36%). Huit patients ont eu une coronarographie et 4 (50%) présentaient des sténoses significatives. Au total, 31 patients (20%) ont montré des signes d'ischémie lors de l'examen non-invasif et 15 (10%) ont présenté des sténoses significatives à la coronarographie. Les facteurs prédictifs indépendants de la maladie coronarienne étaient le tabagisme (OR 6.5, p=0.05), la microalbuminurie (OR 3.9, p=0.03), ainsi que les souffles fémoraux (OR 17.1, p=0.008). Conclusions. En suivant les recommandations américaines, un patient sur cinq présentait une ischémie lors des examens non-invasifs, tandis que 1 sur 10 avait des sténoses significatives à la coronarographie. L'analyse multivariée suggère que des marqueurs des complications micro- et macro-vasculaires en combinaison avec des facteurs de risque cardio-vasculaire classiques pourraient améliorer le pouvoir diagnostic de ces recommandations. SUMMARY Aims. We evaluated the prevalence of coronary artery disease in asymptomatic and atypical chest pain type 2 diabetic patients according to the American Diabetes Association and American College of Cardiology guidelines. Methods. Asymptomatic or atypical chest pain type 2 diabetic patients (n=154), with at least two additional cardiovascular risk factors, were screened for coronary artery disease using stress echocardiography (71%, n=109), myocardial perfusion imaging (26%, n=40) or both (3%, n=5). Results. Stress echocardiography was positive in 16 patients (14%) and 14 had a coronary angiography, revealing significant stenoses in 12 (86%). Myocardial perfusion imaging was positive in 16 patients (36%). Eight patients underwent angiography and 4 (50%) presented significant stenoses. Overall, 31 patients (20%) demonstrated signs of ischemia on non-invasive tests and 15 (10%) presented significant stenoses on coronary angiography. Independent predictors of coronary artery disease were smoking (OR 6.5, p=0.05), microalbuminuria (OR 3.9, p=0.03) and femoral murmur (OR 17.1, p=0.008). Conclusions. Following the guidelines, one in five diabetic patient presented ischemia on noninvasive tests, while one in ten presented significant coronary stenoses. Multivariate analysis suggests that adding markers of micro- and macro-vascular complications to classical cardiovascular risk factors may enhance the diagnostic efficiency of the guidelines.
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Protophloem is a specialized vascular tissue in growing plant organs, such as root meristems. In Arabidopsis mutants with impaired primary root protophloem differentiation, brevis radix (brx) and octopus (ops), meristematic activity and consequently overall root growth are strongly reduced. Second site mutation in the protophloem-specific presumed phosphoinositide 5-phosphatase COTYLEDON VASCULAR PATTERN 2 (CVP2), but not in its homolog CVP2-LIKE 1 (CVL1), partially rescues brx defects. Consistent with this finding, CVP2 hyperactivity in a wild-type background recreates a brx phenotype. Paradoxically, however, while cvp2 or cvl1 single mutants display no apparent root defects, the root phenotype of cvp2 cvl1 double mutants is similar to brx or ops, although, as expected, cvp2 cvl1 seedlings contain more phosphatidylinositol-4,5-biphosphate. Thus, tightly balanced phosphatidylinositol-4,5-biphosphate levels appear essential for proper protophloem differentiation. Genetically, OPS acts downstream of phosphatidylinositol-4,5-biphosphate levels, as cvp2 mutation cannot rescue ops defects, whereas increased OPS dose rescues cvp2 cvl1 defects. Finally, all three mutants display higher density and accelerated emergence of lateral roots, which correlates with increased auxin response in the root differentiation zone. This phenotype is also created by application of peptides that suppress protophloem differentiation, CLAVATA3/EMBRYO SURROUNDING REGION 26 (CLE26) and CLE45. Thus, local changes in the primary root protophloem systemically shape overall root system architecture.
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Stellar-mass black holes have all been discovered through X-ray emission, which arises from the accretion of gas from their binary companions (this gas is either stripped from low-mass stars or supplied as winds from massive ones). Binary evolution models also predict the existence of black holes accreting from the equatorial envelope of rapidly spinning Be-type stars (stars of the Be type are hot blue irregular variables showing characteristic spectral emission lines of hydrogen). Of the ~80 Be X-ray binaries known in the Galaxy, however, only pulsating neutron stars have been found as companions. A black hole was formally allowed as a solution for the companion to the Be star MWC 656 (also known as HD 215227), although that was based on a single radial velocity curve of the Be star, a mistaken spectral classification and rough estimates of the inclination angle. Here we report observations of an accretion disk line mirroring the orbit of the Be star. This, together with an improved radial velocity curve of the Be star through fitting sharp Fe II profiles from the equatorial disk, and a refined Be classification (to that of a B1.5-B2 III star), reveals a black hole of 3.8 to 6.9 solar masses orbiting MWC 656, the candidate counterpart of the gamma-ray source AGL J2241+4454. The black hole is X-ray quiescent and fed by a radiatively inefficient accretion flow giving a luminosity less than 1.6 x 10-7 times the Eddington luminosity. This implies that Be binaries with black-hole companions are difficult to detect by conventional X-ray surveys.
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Myocardial ischaemia-reperfusion (MIR) triggers a sterile inflammatory response important for myocardial healing, but which may also contribute to adverse ventricular remodelling. Such inflammation is initiated by molecular danger signals released by damaged myocardium, which induce innate immune responses by activating toll-like receptors (TLRs). Detrimental roles have been recently reported for TLR2, TLR3 and TLR4. The role of other TLRs is unknown. We therefore evaluated the role of TLR5, expressed at high level in the heart, in the development of myocardial damage and inflammation acutely triggered by MIR. TLR5-/- and wild-type (WT) mice were exposed to MIR (30 min ischaemia, 2 h reperfusion). We measured infarct size, markers of cardiac oxidative stress, myocardial phosphorylation state of mitogen-activated protein (MAP) kinases and AKT, expression levels of chemokines and cytokines in the heart and plasma, as well as cardiac function by echography and conductance volumetry. TLR5-deficient mice had normal cardiac morphology and function under physiological conditions. After MIR, the absence of TLR5 promoted an increase in infarct size and myocardial oxidative stress. Lack of TLR5 fostered p38 phosphorylation, reduced AKT phosphorylation and markedly increased the expression of inflammatory cytokines, whereas it precipitated acute LV (left ventricle) dysfunction. Therefore, contrary to the detrimental roles of TLR2, TLR3 and TLR4 in the infarcted heart, TLR5 is important to limit myocardial damage, inflammation and functional compromise after MIR.
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INTRODUCTION: Acute painful diabetic neuropathy (APDN) is a distinctive diabetic polyneuropathy and consists of two subtypes: treatment-induced neuropathy (TIN) and diabetic neuropathic cachexia (DNC). The characteristics of APDN are (1.) the small-fibre involvement, (2.) occurrence paradoxically after short-term achievement of good glycaemia control, (3.) intense pain sensation and (4.) eventual recovery. In the face of current recommendations to achieve quickly glycaemic targets, it appears necessary to recognise and understand this neuropathy. METHODS AND RESULTS: Over 2009 to 2012, we reported four cases of APDN. Four patients (three males and one female) were identified and had a mean age at onset of TIN of 47.7 years (±6.99 years). Mean baseline HbA1c was 14.2% (±1.42) and 7.0% (±3.60) after treatment. Mean estimated time to correct HbA1c was 4.5 months (±3.82 months). Three patients presented with a mean time to symptom resolution of 12.7 months (±1.15 months). One patient had an initial normal electroneuromyogram (ENMG) despite the presence of neuropathic symptoms, and a second abnormal ENMG showing axonal and myelin neuropathy. One patient had a peroneal nerve biopsy showing loss of large myelinated fibres as well as unmyelinated fibres, and signs of microangiopathy. CONCLUSIONS: According to the current recommendations of promptly achieving glycaemic targets, it appears necessary to recognise and understand this neuropathy. Based on our observations and data from the literature we propose an algorithmic approach for differential diagnosis and therapeutic management of APDN patients.
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La fracture périprothétique du fémur (FPF) représente une complication sérieuse des arthroplasties de hanche. Différents matériels d'ostéosynthèse ont été utilisés pour l'ostéosynthèse des FPFs. Toutefois, aucune étude n'a rapporté les résultats obtenus avec une plaque anatomique non-verrouillée avec des trous excentrés. Les buts de ce travail étaient de présenter 1) le taux de consolidation des FPF traitées par cet implant, 2) les caractéristiques péri-opératoires 3) le taux de complications, et 4) les résultats en terme d'autonomie obtenus après le traitement des FPF du groupe B selon Vancouver avec une plaque anatomique à trous excentrés. Hypothèse L'utilisation de cette plaque permet d'obtenir un taux élevé de consolidation avec un minimum de complications mécaniques. Matériels et Méthodes Quarante-trois patients, d'âge moyen 79 ans ± 13 (41 - 98), qui ont été traités pour une ostéosynthèse d'une FPF de type B selon Vancouver avec cette plaque entre 2002 et 2007 ont été inclus. Les patients ont été classifiées selon les scores ASA et de Charnley. Le temps opératoire, les pertes sanguines chirurgicales, le nombre de transfusion, la durée d'hospitalisation, le délai de consolidation, le lieu de vie ainsi que l'autonomie (score de Parker) ont été évalués. Le taux de survie sans révision a été calculé par la méthode de Kaplan-Meier. Le recul moyen est de 42 mois ± 20 (min - max : 16 - 90). Résultats La consolidation a été obtenue chez tous les patients avec un délai moyen de 2,4 mois ± 0,6 (2-4). 1 patient avec un cal vicieux en varus était à déplorer. Le score de Parker a diminué de 5,93 ± 1,94 (2-9) à 4,93 ± 1,8 (1- 9) (p = 0.01). 2 révisions chirurgicales ont été nécessaires sur la série. Le taux de survie à 5 ans des prothèses après ostéosynthèse de la FPF était de 83,3 % ± 12,6 %. Conclusion Cette plaque anatomique avec trous excentrés permet le traitement des FPF du type B et garantit une consolidation de la fracture avec un faible taux de complications liés à l'ostéosynthèse. Toutefois, les FPF représentent une complication sérieuse des arthroplasties de hanche assortie d'un fort taux de morbidités et de mortalité.
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We have studied the effect of pressure on the structural and vibrational properties of lanthanum tritungstate La2(WO4)3. This compound crystallizes under ambient conditions in the modulated scheelite-type structure known as the α phase. We have performed x-ray diffraction and Raman scattering measurements up to a pressure of 20 GPa, as well as ab initio calculations within the framework of the density functional theory. Up to 5 GPa, the three methods provide a similar picture of the evolution under pressure of α-La2(WO4)3. At 5 GPa, we begin to observe some structural changes, and above 6 GPa we find that the x-ray patterns cannot be indexed as a single phase. However, we find that a mixture of two phases with C2/c symmetry accounts for all diffraction peaks. Our ab initio study confirms the existence of several C2/c structures, which are very close in energy in this compression range. According to our measurements, a state with medium-range order appears at pressures above 9 and 11 GPa, from x-ray diffraction and Raman experiments, respectively. Based upon our theoretical calculations we propose several high-pressure candidates with high cationic coordinations at these pressures. The compound evolves into a partially amorphous phase at pressures above 20 GPa.
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BACKGROUND: There have been inconsistent reports on the potential association between diabetes mellitus and epilepsy. METHODS: We examined a consecutive cohort of 2016 people with pharmacoresistant epilepsy admitted to a tertiary medical centre. RESULTS: We identified 20 individuals with type 1 diabetes mellitus (T1DM); a point prevalence of 9.9 (95% CI: 6.4, 15.3) cases per 1000 individuals. This represents a more than two-fold increase relative to published prevalence estimates of T1DM in the general population. The onset of T1DM preceded that of epilepsy in 80% of individuals, by a median of 1.5 years. Individuals with T1DM were significantly more likely to have cryptogenic/unknown epilepsy relative to those with type 2 diabetes mellitus or without diabetes (85% versus 35% and 49%, p=0.045). All individuals with T1DM had focal epilepsy, the majority of which were temporal lobe in origin, although there was no evidence that this proportion was any different from those without T1DM (p>0.999). CONCLUSIONS: The prevalence of T1DM appears to be increased in people with pharmacoresistant epilepsy and is associated with cryptogenic/unknown epilepsy. These findings may have pathophysiological implications, especially in the context of anti-glutamic acid decarboxylase antibodies.
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Introduction: B-type natriuretic peptide (BNP) is a biomarker of myocardial stress. In children, the value of preoperative BNP on postoperative outcome is unclear. The aim of this study was to determine the predictive value of preoperative NT-proBNP on postoperative outcome in children after congenital heart surgery. Results: Ninety-seven patients were included in the study with a median age of 3.3 years [0.7-5.2]. Preoperative median NT-proBNP was 412 pg/ml [164-1309]. NT-proBNP was above the P95 reference value for age in 56 patients (58%). Preoperative NT-proBNP was significantly higher in patients who had mechanical ventilation duration of more than 2 days (1156 pg/ml [281-1951] vs. 267 pg/ml [136-790], p=0.003) and who stayed more than 6 days in the pediatric intensive care unit (727 pg/ml [203-1951] vs. 256 pg/ml [136-790], p=0.007). However, preoperative NT-proBNP was not significantly higher in patients with an increased inotropic score, a prolonged cardiopulmonary bypass time or an increased surgical risk category. Conclusions: An elevated preoperative NT-proBNP reflects hemodynamic status and cardiac dysfunction, and therefore is a valuable adjunct in predicting a complicated postoperative course. ___________________________________ Introduction: Le peptide natriurétique type B (BNP) est un marqueur reflétant le stress myocardique. Dans la population pédiatrique, la signification des valeurs préopératoire de BNP, en particulier sur l'évolution postopératoire, n'est pas clairement établie. Le but de l'étude est de déterminer la valeur prédictive de la partie NT sérique du BNP (NT-proBNP) sur l'évolution post opératoire d'enfants porteur d'une cardiopathie congénitale et ayant eu une chirurgie cardiaque. Résultats: Nonante-sept enfants ont été inclus dans l'étude, avec un âge médian de 3.3 ans [0.7-5.2]. La valeur médiane du NT-proBNP préopératoire était de 412 pg/ml [164-1309]. Le NT-proBNP préopératoire était supérieur au P95 des valeurs de référence pour l'âge chez 56 patients (58%). Le NT-proBNP préopératoire était significativement plus élevé chez les patients ayant eu plus de deux jours de ventilation mécanique dans la période postopératoire (1156 pg/ml [281-1951] vs. 267 pg/ml [136-790], p=0.003) et ayant été hospitalisés plus de 6 jours dans l'unité de soins intensifs pédiatrique (727 pg/ml [203-1951] vs. 256 pg/ml [136-790], p=0.007). Par contre, le NT-proBNP préopératoire n'était pas significativement plus élevé chez les patients ayant eu un score d'inotrope élevé pendant leur hospitalisation aux soins intensifs, un temps de circulation extracorporelle prolongé ou ayant subi une chirurgie avec un risque chirurgical élevé. Conclusions: Un NT-proBNP sérique élevé en préopératoire reflète l'importance du stress myocardique induit par l'hémodynamique et la dysfonction myocardique, il est un marqueur qui permet d'améliorer l'identification des patients à risque d'avoir une évolution post opératoire compliquée.
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AIMS/HYPOTHESIS: Exposure of pancreatic beta cells to cytokines released by islet-infiltrating immune cells induces alterations in gene expression, leading to impaired insulin secretion and apoptosis in the initial phases of type 1 diabetes. Long non-coding RNAs (lncRNAs) are a new class of transcripts participating in the development of many diseases. As little is known about their role in insulin-secreting cells, this study aimed to evaluate their contribution to beta cell dysfunction. METHODS: The expression of lncRNAs was determined by microarray in the MIN6 beta cell line exposed to proinflammatory cytokines. The changes induced by cytokines were further assessed by real-time PCR in islets of control and NOD mice. The involvement of selected lncRNAs modified by cytokines was assessed after their overexpression in MIN6 cells and primary islet cells. RESULTS: MIN6 cells were found to express a large number of lncRNAs, many of which were modified by cytokine treatment. The changes in the level of selected lncRNAs were confirmed in mouse islets and an increase in these lncRNAs was also seen in prediabetic NOD mice. Overexpression of these lncRNAs in MIN6 and mouse islet cells, either alone or in combination with cytokines, favoured beta cell apoptosis without affecting insulin production or secretion. Furthermore, overexpression of lncRNA-1 promoted nuclear translocation of nuclear factor of 54; light polypeptide gene enhancer in B cells 1 (NF- 54;B). CONCLUSIONS/INTERPRETATION: Our study shows that lncRNAs are modulated during the development of type 1 diabetes in NOD mice, and that their overexpression sensitises beta cells to apoptosis, probably contributing to their failure during the initial phases of the disease.
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Amitriptyline is a tricyclic antidepressant, considered the treatment of choice for different types of chronic pain, including chronic myofascial pain. Its antinociceptive property is independent of its antidepressant effect. Although its analgesic mechanism is not precisely known, it is believed that the serotonin reuptake inhibition in the central nervous system plays a fundamental role in pain control. Although this medication is widely used in the prevention of chronic tension-type headache, few studies have investigated the efficacy of this treatment and the published results are contradictory. The objective of this article was to review the literature published on the use of amitriptyline in the prophylactic treatment of chronic tension-type headache, considering the level of scientific evidence of the different studies using the SORT criteria. From this review, 5 articles of evidence level 1, and another 5 articles of evidence level 2 were selected. Following analysis of the 10 studies, and in function of their scientific quality, a level A recommendation was made in favor of using amitriptyline in the treatment of chronic tension-type headache.