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BACKGROUND AND PURPOSE: The aim was to assess functional and radiological outcomes after bridging therapy (intravenous thrombolysis plus mechanical thrombectomy) versus direct mechanical thrombectomy (MT) in unknown onset stroke patients. METHODS: A cohort study was conducted on prospectively collected data from unknown onset stroke patients who received endovascular procedures at ≤6 h from symptom recognition or awakening time. RESULTS: Of the 349 patients with a 10-point Alberta Stroke Program Early Computed Tomography Score (ASPECTS), 248 received bridging and 101 received direct MT. Of the 134 patients with 6-9-point ASPECTS, 123 received bridging and 111 received direct MT. Each patient treated with bridging was propensity score matched with a patient treated with direct MT for age, sex, study period, pre-stroke disability, stroke severity, type of stroke onset, symptom recognition to groin time (or awakening to groin time), ASPECTS and procedure time. In the two matched groups with 10-point ASPECTS (n = 73 vs. n = 73), bridging was associated with higher rates of excellent outcome (46.6% vs. 28.8%; odds ratio 2.302, 95% confidence interval 1.010-5.244) and successful recanalization (83.6% vs. 63%; odds ratio 3.028, 95% confidence interval 1.369-6.693) compared with direct MT; no significant association was found between bridging and direct MT with regard to rate of symptomatic intracerebral hemorrhage (0% vs. 1.4%). In the two matched groups with 6-9-point ASPECTS (n = 45 vs. n = 45), no significant associations were found between bridging and direct MT with regard to rates of excellent functional outcome (44.4% vs. 31.1%), successful recanalization (73.3% vs. 76.5%) and symptomatic intracerebral hemorrhage (0% vs. 0%). CONCLUSIONS: Bridging at ≤ 6 h of symptom recognition or awakening time was associated with better functional and radiological outcomes in unknown onset stroke patients with 10-point ASPECTS.
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Isquemia Encefálica , Accidente Cerebrovascular , Alberta , Isquemia Encefálica/tratamiento farmacológico , Estudios de Cohortes , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Trombectomía , Terapia Trombolítica , Resultado del TratamientoRESUMEN
BACKGROUND: Sarcopenia was reported to be associated with poor clinical outcome, higher incidence of community-acquired pneumonia, increased risk of infections and reduced survival in different clinical settings. The aim of our work is to evaluate the prognostic role of sarcopenia in patients with the 2019 novel coronavirus disease (COVID-19). MATERIALS AND METHODS: 272 COVID-19 patients admitted to the University Hospital of Modena (Italy) from February 2020 to January 2021 were retrospectively studied. All included patients underwent a chest computed tomography (CT) scan to assess pneumonia during their hospitalization and showed a positive SARS-CoV-2 molecular test. Sarcopenia was defined by skeletal muscle area (SMA) evaluation at the 12th thoracic vertebra (T12). Clinical, laboratory data and adverse clinical outcome (admission to Intensive Care Unit and death) were collected for all patients. RESULTS: Prevalence of sarcopenia was high (41.5%) but significantly different in each pandemic wave (57.9% vs 21.6% p < 0.0000). At the multivariate analysis, sarcopenia during the first wave (Hazard Ratio 2.29, 95% confidence intervals 1.17 to 4.49 p = 0.0162) was the only independent prognostic factor for adverse clinical outcome. There were no significant differences in comorbidities and COVID19 severity in terms of pulmonary involvement at lung CT comparing during the first and second wave. Mixed pattern with peripheral and central involvement was found to be dominant in both groups. CONCLUSION: We highlight the prognostic impact of sarcopenia in COVID-19 patients hospitalized during the first wave. T12 SMA could represent a potential tool to identify sarcopenic patients in particular settings. Further studies are needed to better understand the association between sarcopenia and COVID-19.
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COVID-19 , Sarcopenia , Humanos , Pandemias , Estudios Retrospectivos , SARS-CoV-2 , Sarcopenia/diagnóstico , Sarcopenia/epidemiologíaRESUMEN
Perimenopause and menopause may be associated with an increased risk of cardiovascular disease, so we have investigated the cardiovascular and catecholamine response to caffeine in perimenopausal women compared to young cycling premenopausal subjects. Caffeine (250 mg per os) was administered to nine perimenopausal women and nine premenopausal women. The perimenopausal women repeated the test after 4 months of percutaneous estrogen replacement therapy. Systolic and diastolic blood pressure, pulse rate, plasma norepinephrine, epinephrine, glucose, insulin and free fatty acids were determined at 0, 15, 30, 45, 60, 90 and 120 min after caffeine administration. No differences were found in the basal values of systolic blood pressure, diastolic blood pressure, pulse rate, norepinephrine, epinephrine, insulin, glucose and free fatty acids between perimenopausal women, both before and after therapy, and premenopausal women. Caffeine induced a higher increase of systolic (F = 4.9; p < 0.05) and diastolic blood pressure (F = 4.7; p < 0.05) in perimenopausal women before and during estrogen therapy as compared with premenopausal women. Pulse rate increased significantly only in perimenopausal women before therapy (F = 6.5; p < 0.03). These data show that perimenopause either before or during short-term estrogen therapy is associated with enhanced cardiovascular reactivity to caffeine. This phenomenon is not due to increased adrenergic and metabolic responses.
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Cafeína/farmacología , Sistema Cardiovascular/efectos de los fármacos , Terapia de Reemplazo de Estrógeno , Premenopausia , Adulto , Glucemia/análisis , Catecolaminas/sangre , Ácidos Grasos no Esterificados/sangre , Femenino , Gonadotropinas Hipofisarias/sangre , Humanos , Insulina/sangreRESUMEN
OBJECTIVE: Alterations in catecholamine plasma levels may contribute to the cardiovascular complications of acromegaly. Since few data are available on the catecholamine secretory dynamics in active acromegaly and no evidence exists on catecholamine variations during GH decrease, we studied acromegalic patients before and during octreotide administration. METHODS: We evaluated the catecholamine responses to upright posture and a cold pressure test (CPT) in 11 acromegalic (A) patients before and during continuous administration of octreotide (500 microgram/24h by s.c. pump) compared with 11 normal (N) subjects. RESULTS: All the acromegalic patients showed left ventricular cardiac hypertrophy. The cardiovascular responses to upright posture were similar between normal subjects and acromegalics both before and during octreotide treatment. The basal levels of norepinephrine (NE) were significantly higher in A patients compared with N subjects (423+/-45 vs 264+/-32pg/ml, P<0. 05) and decreased during therapy (291+/-32pg/ml; P<0.01). The increase in plasma NE during upright posture was significantly lower in A than in N subjects (P<0.01), but was restored to normal during octreotide treatment. CPT increased systolic and diastolic blood pressure, pulse rate and NE plasma levels in N (P<0.05) but not in A subjects both before and during octreotide treatment. CONCLUSIONS: Our data demonstrate the presence of increased basal NE levels in acromegalic patients with a defective sympathetic response to stimuli. Short-term octreotide infusion is able to induce a reduction in the basal levels of NE and a normalization of the catecholamine response to posture.
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Acromegalia/metabolismo , Acromegalia/fisiopatología , Presión Sanguínea , Epinefrina/metabolismo , Hormonas/uso terapéutico , Norepinefrina/metabolismo , Octreótido/uso terapéutico , Acromegalia/tratamiento farmacológico , Adulto , Frío , Diástole , Femenino , Mano , Humanos , Inmersión , Bombas de Infusión , Masculino , Persona de Mediana Edad , Postura , Valores de Referencia , Sístole , Factores de TiempoRESUMEN
OBJECTIVE: To determine whether the opioidergic system is involved in the modulation of leptin secretion in healthy and amenorrheic subjects. DESIGN: Prospective study. SETTING: Department of Obstetrics and Gynecology, University of Modena, Modena, Italy. PATIENT(S): Healthy subjects (n = 8) and patients with hypothalamic amenorrhea (n = 17) or hyperandrogenism (n = 7) and low body mass index (BMI). INTERVENTION(S): Acute infusion of naloxone (4-mg bolus) and blood sampling 15 minutes before infusion; at time of infusion; and 15, 30, 45, 60, 75, 90, and 120 minutes after infusion. MAIN OUTCOME MEASURE(S): Plasma leptin, LH, FSH, E2, and cortisol concentrations. RESULT(S): Plasma leptin concentrations were lower (P <.01) in both hypothalamic and hyperandrogenic amenorrheic subjects than in healthy controls. In all groups of subjects, no significant changes in leptin levels were observed after infusion of naloxone. A significant correlation was found between leptin concentrations and BMI when all subjects were considered together (P <.05) but was not found in the single groups. CONCLUSION(S): The present data do not support the hypothesis that opioidergic receptors are involved acutely in the modulation of leptin release in healthy and amenorrheic women.
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Amenorrea/sangre , Naloxona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Proteínas/metabolismo , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Hiperandrogenismo/sangre , Enfermedades Hipotalámicas/sangre , Infusiones Intravenosas , Leptina , Tasa de Secreción/efectos de los fármacosRESUMEN
OBJECTIVE: Cardiovascular disease seems to increase after the menopause and is thought to be reduced by estrogen replacement therapy. Among the many studies which have tried to define the multifactorial mechanisms of estrogens cardiovascular prevention, very few have focused on their possible modulation of adrenergic activity. In the present study we investigated whether prolonged estradiol replacement via transdermal patches is able to modulate cardiovascular and adrenergic responses to stimuli. METHODS: Baseline and responses to a cold stimulus and to the upright position of catecholamines (epinephrine and norepinephrine), heart rate, systolic and diastolic blood pressure were investigated in 15 healthy volunteer postmenopausal women both prior to and after 2 months of treatment with patches rated to deliver 50 microg/day of estradiol. RESULTS: Basal norepinephrine levels (P<0.005), as well as their integrated responses to the cold stimulus (P<0.02) were lower during estradiol. By contrast, responses of norepinephrine to the upright test, as well as basal and responses to stimuli of epinephrine and circulatory parameters were not different before and during estradiol. CONCLUSIONS: Estradiol replacement at low doses significantly decreases overall sympathetic output, both in basal conditions and under specific stimuli. These effects whether maintained or magnified in the long term may play a role in the prevention of the postmenopausal cardiovascular risk.
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Catecolaminas/sangre , Estradiol/farmacología , Hemodinámica/efectos de los fármacos , Administración Cutánea , Índice de Masa Corporal , Enfermedades Cardiovasculares/prevención & control , Estradiol/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Valores de Referencia , Sistema Nervioso Simpático/efectos de los fármacosRESUMEN
It is well known that the pituitary PRL secretion is modified in patients with primary hypothyroidism. The serum PRL is elevated in approximately one third of patients, the others presenting with enhanced PRL release after TRH intravenous (i.v.) administration. The objective of this study was to verify how treatment with L-thyroxine modifies the enhanced PRL response to TRH administration in a group of patients with primary hypothyroidism. Eight female patients aged 28 to 64 (mean age +/- SD = 17.2 +/- 6.0) with primary hypothyroidism were studied. Diagnosis was based on clinical features and plasma FT4 (mean +/- SD = 5.2 +/- 0.9 pmol/l; n.r. 7.7-19.3 pmol/l) and TSH (mean +/- SD = 87.3 +/- 20 mUI/l; n.r. 0.2-5 mUI/l) levels. As controls eleven normal age-matched female subjects were also studied. After an overnight fasting an indwelling catheter was inserted into an antecubital vein of the forearm and kept patient by slow infusion of normal saline solution. After 60' the basal blood sample was collected and 200 mcg of TRH was injected intravenously (0'), further blood samples were taken at 30', 60', 90', 120' and 180'. PRL determinations (n.r. 3-19 ng/ml) of the blood samples obtained were made using fluoroimmunometric assay. Hypothyroid patients underwent a second TRH test after L-thyroxine replacement therapy (100 mcg/day) had led to euthyroidism for at least three months.(ABSTRACT TRUNCATED AT 250 WORDS)
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Hiperprolactinemia/etiología , Hipotiroidismo/tratamiento farmacológico , Tiroxina/uso terapéutico , Adulto , Femenino , Humanos , Hipotiroidismo/fisiopatología , Persona de Mediana Edad , Prolactina/metabolismo , Hormona Liberadora de Tirotropina/farmacologíaRESUMEN
The persistent hypoglossal artery is a rare perseverance of an embryonic vessel connecting the anterior and posterior circulations and is generally considered an incidental finding. This report describes a patient with a basilar dependence on a persistent hypoglossal artery visualized at CT angiography. The pertinent findings and clinical implications of this anomalous vessel are discussed.
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Dural arteriovenous fistulas (DAVF) are vascular malformations rarely occurring in the paediatric population (1,2,3). Prompt diagnosis and treatment are mandatory to prevent life-threatening complications including congestive heart failure and severe brain injury (1,2). We describe the case of a female newborn with an orbital lymphangioma treated for a posterior fossa DAVF. We emphasize the role of MR imaging as a useful non-invasive tool in the diagnosis of these malformations and in the evaluation of associated brain parenchymal lesions.
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Refractures of cemented vertebrae occasionally occur after vertebroplasty. It is unclear whether such fractures are procedure-related or part of the natural course of osteoporosis and neoplasy. Our aim was to identify why there is an increased risk of subsequent fracture in cemented vertebrae. We retrospectively analyzed the incidence and possible causative mechanism of refracture in patients who had received vertebroplasty for multiple levels of vertebral compression fracture and the reduction of pain after a subsequent vertebroplasty procedure. A total of 356 patients were evaluated with follow-up from June 2003 to September 2008. We identified 59 refractured patients (54 osteoporotic and four neoplastic). Refractures of cemented vertebrae after vertebroplasty occurred in 59 patients (16%: 98% osteoporotic and 2% neoplastic). Refractures occurred in 8% at the same level as the first vetebroplasty, 31% at an inferior level, 19% at a superior level, 41% at superior and inferior levels and 1% at superior and same levels. Pain was significantly reduced after retreatment in 45 patients (76%) with a moderate reduction in 14 patients (24 %). In conclusion, significant anterior vertebral height restoration increases the risk of subsequent fracture in cemented vertebrae.
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To demonstrate that percutaneous sclerotherapy for lymphangioma using a new fibrosing agent (OK-432) and for soft-tissue venous malformation with alcoholization can improve management of these congenital vascular abnormalities. Between February 2003 and November 2005 five patients with lymphangioma, ranging in age from 23 months to 18 years (mean age = 9 years) and four patients with soft-tissue venous malformation, raging in age from 25 months to 18 years (mean age = 11 years) underwent percutaneous sclerotherapy. Ultrasound Computed tomography and/or Magnetic Resonance imaging were performed beforehand to evaluate the anatomic boundaries of the malformation. General anesthesia is mandatory for children under three years. Direct puncture of the mass with a 23-gauge venous infusion set (butterfly) was performed by means of palpation alone or with ultrasonographic guidance using OK-432 PICIBANIL (0.1-0.2 mg dilute in 10 ml normal saline) for lymphangioma and alcohol in venous malformation. The volume of sclerosing solution varied from 0.2 to 15 ml per injection course. Processing time was less than 20 minutes. Swelling of lesion, pain, local inflammatory reactions and mild fever (37.5°-39°) in lymphangioma, were constant findings after sclerotherapy. Satisfactory results (when the regression was estimated to be more than 50% of the initial volume; negative in inspection, but positive in palpation and imaging study) were obtained in four patients with head and neck lymphangioma. One patient was completely cured with an excellent (when there was a complete regression of malformations; negative in inspection, palpation and imaging study) result. All patients with soft-tissue venous malformation were satisfied with the results. In conclusion, in consideration of its low cost, rare complications and good results, we strongly recommend percutaneous sclerotherapy in the treatment of head and neck lymphangioma and soft-tissue venous malformation in children.
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Radiological diagnosis of osteoid-osteoma is based upon conventional radiographic techniques, i.e. plain film and tomography, scintigraphy and Computed Tomography (CT). The authors report on the use of CT in 13 patients affected by histologically verified osteoid-osteoma, in different locations, as related to their main clinical and epidemiological signs. A comparison is made of the diagnostic contribution of the different techniques, including scintigraphy and tomography, when available. CT results were evaluated referring to fundamental semiologic elements, such as the presence of the nidus--with or without calcifications--of perilesional sclerosis, hyperostosis and periosteosis. As a rule, we can affirm that CT allows a better spatial location in the metaphysodiaphyso-epiphyseal areas, the only exception being represented by location in the metacarpal and phalangeal bones, which are better evaluated in the axial plane due to their thinness. CT is otherwise indispensable for a correct evaluation of the posterior vertebral arch.
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Neoplasias Óseas/diagnóstico por imagen , Osteoma Osteoide/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Epífisis/diagnóstico por imagen , Femenino , Neoplasias Femorales/diagnóstico por imagen , Dedos/diagnóstico por imagen , Humanos , Húmero/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Masculino , Metacarpo/diagnóstico por imagen , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Tibia/diagnóstico por imagenRESUMEN
One hundred and fifteen patients, suffering from sensorineural hearing loss were tested with a 1.5 T superconducting magnet. The authors describe utility of both T1-weighted multiple slice and T2-weighted multiple echo images for the evaluation of cerebello-pontine angle, internal auditory canal and their neurovascular content. In seventy-three cases MR cisternography was normal. The remaining forty-two cases were subdivided into twenty extracanalicular masses, eleven small intra-extracanalicular and nine purely intracanalicular lesions. All the lesions were histologically proven acoustic neuromas, except one intracanalicular mass which was a meningioma. Examination was inconclusive only in two cases and decision was then made to follow the clinical course. Advantages of MR cisternography over CT and air CT cisternography, such as absence of ionizing radiation and contrast material, easy multiplanar evaluation of the region of interest and the possibility to delineate both the cisternal and canalar extremities of the tumor mass are pointed out.
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Ángulo Pontocerebeloso/patología , Oído Interno/patología , Imagen por Resonancia Magnética , Neuroma Acústico/diagnóstico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/patologíaRESUMEN
Although intravenous (i.v.) heparin is widely used as the first line treatment for cerebral venous and sinus thrombosis (CVST), the most appropriate therapy for this disease is still controversial. We report 2 cases of CVST who were successfully treated by means of loco-regional thrombolysis with urokinase. In the first case we chose this treatment instead of i.v. heparin because clinical conditions of the patient appeared critical for life on hospital admission; in the second case loco-regional thrombolysis was performed because a full-dose heparin treatment over 8 days failed to improve the clinical picture of the patient. In the literature, there are no established criteria for the use of loco-regional thrombolysis in CVST. On the basis of our own experience and few previous reports on the matter, we suggest that loco-regional thrombolysis should be considered an appropriate treatment for CVST when patients are at life risk, when an involvement of deep cerebral veins is present or when, after full heparinization, patients are doing poorly clinically.
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Venas Cerebrales , Embolia Intracraneal/tratamiento farmacológico , Trombosis de los Senos Intracraneales/tratamiento farmacológico , Terapia Trombolítica , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificación , Angiografía Cerebral , Venas Cerebrales/diagnóstico por imagen , Quimioterapia Combinada , Femenino , Heparina/administración & dosificación , Humanos , Infusiones Intravenosas , Embolia Intracraneal/diagnóstico por imagen , Persona de Mediana Edad , Trombosis de los Senos Intracraneales/diagnóstico por imagenRESUMEN
The reduction in resting metabolic rate (RMR) during weight loss exceeds that accounted for by changes in body composition by 15%, suggesting that factors other than fat-free mass (FFM) explain the metabolic adaptation during food restriction in obesity. Our study aimed to establish if changes in the sympathoadrenal system activity, as inferred from an integrated measure such as 24 h urinary excretion of catecholamines, may play a role in the RMR adaptation observed during dietary restriction in obese patients. Ninety-three obese female subjects consumed a low-energy diet (LED) (2930 kJ/d (700 kcal/d)) for a 3-week period. At the beginning and at the end of the study, 24 h urinary excretion of catecholamines, FFM and RMR were measured. The LED induced a significant reduction in body weight (-3.3 (SEM 0.4) kg; P < 0.01), FFM (-1.9 (SEM 0.7) kg; P < 0.01) and in the fat mass (-1.2 (SEM 0.5) kg; P < 0.01). Noradrenalin excretion (24 h) decreased during the LED from 264 (SEM 26) during a weight-maintenance period to 171 (SEM 19) nmol/24 h after consumption of the LED for 3 weeks (P < 0.001); mean 24 h adrenalin excretion did not change during the LED (22 (SEM 3) during the weight-maintenance period v. 21 (SEM 3) nmol/24 h after consumption of the LED for 3 weeks; NS). The LED induced a significant decrease in RMR (7300 (SEM 218) v. 6831 (SEM 138) kJ/24 h; P < 0.001). The only independent variable that significantly explained variations in RMR both before and after consumption of the LED for 3 weeks, was FFM (r2 0.79 and r2 0.80 respectively). Urinary noradrenalin excretion explained a further 4% of the variability in RMR, but only before the diet, so that a role of sympathoadrenal system on RMR seems to be present in obese patients in basal conditions but not at the end of the LED.
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Metabolismo Basal/fisiología , Catecolaminas/orina , Obesidad/metabolismo , Pérdida de Peso/fisiología , Adolescente , Adulto , Composición Corporal , Calorimetría Indirecta , Dieta Reductora , Epinefrina/orina , Femenino , Humanos , Persona de Mediana Edad , Norepinefrina/orina , Obesidad/dietoterapia , Análisis de RegresiónRESUMEN
Our objective was to assess thermogenic action of fluoxetine (FL) in obese menopausal women, evaluating the effect of FL administration on resting energy expenditure (REE) and on glucose-induced thermogenesis both after acute administration (40 mg in single dose the evening before measurements) and after a 12- week period of diet treatment plus FL (60 mg per day) or placebo. It was a double-blind, placebo-controlled design both in acute and in chronic study. The subjects were 32 obese, otherwise healthy, menopausal women. The patients were assigned randomly to three groups, one performing an acute study protocol, in which resting and glucose-induced thermogenesis was measured after FL and placebo administration, performed in randomised order. The other two groups underwent dietary plus pharmacological treatment (FL or placebo, PL). Resting and glucose-induced thermogenesis was measured at baseline and after 12 weeks of treatment. The results showed that acute FL administration caused an increase in resting energy expenditure (PL: 5.35+/-0.18 vs FL: 5.53+/-0.24 KJ/min, p<0.05). A significant decrease of REE was observed in the PL group after 12 weeks (p<0.03), while a slight, but not significant, decrease was observed in the FL group (p=NS). FL did not affect thermic response to oral glucose neither after acute nor chronic administration (p=NS for all groups studied). The conclusion was that our data give support to thermogenic actions of FL after acute administration, suggesting also that chronic FL treatment may restrain to some degree the metabolic adaptation expected during weight loss in obese subjects. At variance with what observed with other drugs, such as dexfenfluramine, an increased thermic effect of oral glucose does not seem to be involved in the thermogenetic action of FL.
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Antidepresivos de Segunda Generación/farmacología , Regulación de la Temperatura Corporal/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Fluoxetina/farmacología , Menopausia , Obesidad/metabolismo , Antidepresivos de Segunda Generación/administración & dosificación , Antidepresivos de Segunda Generación/uso terapéutico , Glucemia/análisis , Método Doble Ciego , Ayuno , Femenino , Fluoxetina/administración & dosificación , Fluoxetina/uso terapéutico , Glucosa/administración & dosificación , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Persona de Mediana Edad , Obesidad/dietoterapia , Placebos , Pérdida de PesoRESUMEN
The authors retrospectively examined one hundred and twenty-nine patients who had undergone MR examination of the sellar, parasellar and orbital regions, to evaluate MR capabilities in demonstrating the optic pathways and their relationship to the most important anatomical structures nearby. T1-weighted images allowed a very good evaluation not only of the optic pathways as a whole, but also of the intracanalicular and intracranial segments of the optic nerve; the optic tracts and geniculate bodies were also clearly demonstrated. Optic radiations were clearly visible on both T1- and T2-weighted images. The orbital portion of the optic nerve could be evaluated with T1-weighted images, which showed its external profile. However, only multi-echo T2-weighted images allowed the nerve to be differentiated from perineural spaces, filled with cerebrospinal fluid, thus giving a true cisternographic effect.
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Imagen por Resonancia Magnética/métodos , Quiasma Óptico/anatomía & histología , Cuerpos Geniculados/anatomía & histología , Humanos , Lóbulo Occipital/anatomía & histología , Nervio Óptico/anatomía & histología , Órbita , Silla TurcaRESUMEN
OBJECTIVE: In young individuals melatonin administration reduces circulating norepinephrine. Some effects of melatonin are reduced in elderly women and are modulated by gonadal steroids. Accordingly, the influence of melatonin on catecholamine levels was investigated in postmenopausal women without and with oestradiol replacement. DESIGN: Prior to and after 2 months of transdermal oestradiol (50 microg/day), women were studied on two consecutive days, on which they received placebo or 1 mg of melatonin orally in a randomised and double-blind fashion. PATIENTS: Fourteen healthy postmenopausal women. MEASUREMENTS: Resting levels of epinephrine and norepinephrine and their responses to both a cold stimulus, performed by placing a hand in a basin of water and ice for 2 minutes, and to 10 minutes of upright position (upright test). RESULTS: Prior to oestradiol, melatonin did not modify baseline or stimulated catecholamine levels. In contrast, during oestradiol, melatonin tended to reduce, although not significantly, baseline norepinephrine levels (P = 0.053), and significantly reduced peak values (P = 0.0061) and integrated norepinephrine response (P = 0.0076) to the cold stimulus. Responses of norepinephrine to the upright test were not modified, while those of epinephrine were increased (P = 0.042). During, but not prior to oestradiol replacement, modifications induced by melatonin (melatonin day-placebo day) in the norepinephrine response to the cold (r2 = 0. 457; P = 0.0079) and the upright (r2 = 0.747; P = 0.0001) tests were linearly and inversely related to the responses of the placebo day. CONCLUSIONS: Melatonin does not modulate adrenergic activity in postmenopausal women without hormone replacement therapy. Oestradiol replacement restores the capability of melatonin to modulate adrenergic activity, particularly the norepinephrine response to stimuli.
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Catecolaminas/sangre , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Melatonina/farmacología , Menopausia/sangre , Frío , Método Doble Ciego , Epinefrina/sangre , Femenino , Humanos , Persona de Mediana Edad , Norepinefrina/sangre , Postura , Análisis de RegresiónRESUMEN
Lipid alterations and increased blood pressure may occur during perimenopause. No data are available in perimenopausal women on the alpha-2 adrenergic activity which affects norepinephrine secretion. We studied cardiovascular and catecholamine responses to clonidine (300 mg per os) in a group of 15 perimenopausal women (PeriMW) and in a control group of 13 premenopausal women (PreMW). Nine of the perimenopausal women were also studied after 4-month percutaneous estrogen replacement therapy (PeriMWE). Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), plasma norepinephrine (NE) and epinephrine (E) were evaluated before and at 120 min, 130 min, 140 min after clonidine administration. Basal values of SBP, DBP and HR were not different (F = 0.7, p = NS; F = 0.2, p = NS and F = 0.1, p = NS respectively) between PeriMW both before and after therapy and PreMW. Resting levels of E were similar in PreMW and in PeriMW before and during estrogen therapy (F = 0.8, p = NS); PeriMW showed higher basal NE levels both before and during estrogen therapy than PreMW (F = 12; p < 0.001). Clonidine administration decreased SBP, DBP and NE levels in PreMW, in PeriMW and in PeriMWE without any difference between the groups (F = 1.2, p = NS; F = 0.5, p = NS and F = 1.3, P = NS respectively). HR decreased significantly after clonidine in PreMW (F = 5.4, p < 0.03) but not in PeriMW before (F = 1.0, p = NS) and during estrogen therapy (F = 0.5, p = NS). Clonidine did not affect plasma E in the three groups studied (F = 2.8, p = NS; F = 2.2, P = NS and F = 0.1, p = NS). The present study demonstrates that increased basal plasma NE levels are present in PeriMW. The cardiovascular and catecholamine response to clonidine in PeriMW both before and during estrogen therapy are similar to those observed in PreMW, suggesting a normal inhibitory alpha-2 receptor pathway.
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Menopausia/fisiología , Receptores Adrenérgicos alfa/fisiología , Agonistas alfa-Adrenérgicos , Adulto , Presión Sanguínea , Clonidina , Epinefrina/sangre , Terapia de Reemplazo de Estrógeno , Femenino , Frecuencia Cardíaca , Humanos , Cinética , Persona de Mediana Edad , Norepinefrina/sangreRESUMEN
OBJECTIVE: To investigate whether blunted adrenomedullary responsiveness to stimuli is a primary feature of human obesity in childhood and adolescence DESIGN: Comparison of plasma catecholamine response to caffeine in obese and lean subjects before and after puberty onset. SUBJECTS: Twelve lean prepubertal subjects (six males and six females), 15 prepubertal obese subjects (seven males and eight females), 12 pubertal lean subjects (six males and six females) and 24 pubertal obese subjects (12 males and 12 females) MEASUREMENTS: Plasma levels of Luteinizing hormone (LH), follicle-stimulating hormone (FSH), 17beta-estradiol and testosterone were used to validate Tanner score. Systolic and diastolic blood pressure, pulse rate and plasma catecholamines before and after caffeine administration (4 mg/kg of ideal body weight). RESULTS: Caffeine administration significantly stimulated adrenaline release in all subjects studied. The incremental area of adrenaline response to caffeine, analysed by multiple comparison test, was lower in pubertal obese subjects with respect to other groups. CONCLUSIONS: At variance with what is observed in adulthood obesity, prepubertal obese subjects show an intact adrenomedullary response to caffeine.