Deforestation has a large impact on soil fertility, especially on steep slopes, but by applying sustainable management practices, local communities in Oaxaca (Mexico) have tried to avoid the most negative effects on the forest ecosystems they manage. In this study, the characteristics and bacterial community structure were investigated from soil sampled in triplicate (n = 3) with different land use, i.e.
View Article and Find Full Text PDFBackground: Ischemic colitis (IC) is caused by a transient hypo-perfusion of the colon leading to mucosal ulcerations, inflammation, and hemorrhage. The primary aim was to identify predictive factors of endoscopic severity of IC. Secondary endpoints were to show epidemiology, clinical presentation, endoscopic findings, and outcomes of IC.
View Article and Find Full Text PDFAutoimmune encephalitis refers to a group of pathologies described in the last two decades, characterized by neuropsychiatric symptoms of subacute presentation, mediated by antibodies directed against neuronal membrane proteins. Within this group, encephalitis mediated by antibodies against the NMDA receptor of glutamate is a particular clinical entity, given that its expression is dominated by psychiatric symptoms that usually occur at the onset of the disease. In this paper we describe five cases of NMDA encephalitis in adult patients followed up in the last four years in a public hospital in the City of Buenos Aires, Argentina.
View Article and Find Full Text PDFObjective: To assess body distribution and timing of appearance of rest tremor in Parkinson's disease.
Methods: Information was obtained by a computerized database containing historical information collected at the first visit and data collected during the subsequent follow-up visits. Information on rest tremor developed during the follow-up could be therefore obtained by our own observation in a proportion of patients.
Objectives: Cytotoxic associated gene-A (CagA)-positive strains of Helicobacter pylori emerged as a possible atherosclerotic stimulus. Nevertheless, whether CagA-positivity is associated with more extensive or severe atherosclerotic coronary burden has never been studied.
Methods: Forty consecutive patients with coronary artery disease (CAD) and twenty consecutive patients with normal coronary arteries undergoing coronary angiography were enrolled.
Several studies have investigated potential role of Helicobacter pylori (Hp) in the pathogenesis of atherosclerosis. Postulated mechanisms are various, even though results are still controversial. Here we propose an overview of actual knowledge about this topic, comparing studies in favour with those against the relationship between Hp and atherosclerosis.
View Article and Find Full Text PDFMigraine is characterized by reduced habituation of multimodal evoked potentials, which in turn reflects an abnormal pattern of cortical excitability. We assessed the effects of a 2-month treatment with topiramate or levetiracetam vs placebo on contingent negative variation (CNV) habituation and amplitude in a cohort of migraine without aura (MO) patients. Forty-five MO patients were selected from a university-based outpatient clinic and randomly assigned to 100mg topiramate or 1000mg levetiracetam or placebo in a double-blind design.
View Article and Find Full Text PDFObjective: Recent theories about migraine pathogenesis have outlined an abnormal central processing of sensory signals, also suggested by an abnormal pattern of EEG hyper-synchronization under visual stimulation. The aim of the present study was to test the efficacy of topiramate and levetiracetam vs placebo in a double blind project observing the effects of the three treatments on the EEG synchronization in the alpha band under sustained flash stimulation.
Methods: Forty-five migraine without aura outpatients (MO) were selected and randomly assigned to 100mg topiramate, 1000 mg levetiracetam or placebo treatment.
Hypnic headache is a rare cause of benign headache in the elderly. This is a clinical report of a 67-year-old housewife, suffering from hypnic headache, in which topiramate yielded a successful prophylactic effect at 100 mg/day.
View Article and Find Full Text PDFA reduced habituation of averaged laser-evoked potential (LEP) amplitudes was previously found in migraine patients. The aim of the present study was to assess the habituation of single LEP responses and pain sensation during the interictal phase in migraine patients. Fourteen migraine patients were compared with ten control subjects.
View Article and Find Full Text PDFObjective: The aim of this study was to perform a topographic and dipolar analysis of nociceptive-evoked responses obtained by laser stimulus under basal conditions in a cohort of chronic migraine (CM) patients, compared with migraine without aura (MWA) patients and noncraniofacial pain controls.
Background: An increased activation of cortical areas devoted to the emotional and attentive components of pain was previously found during the course of the migraine attack; it was more pronounced in patients reporting higher frequency of migraine.
Methods: Twenty-six outpatients were enrolled in the study; 16 fulfilled the criteria of CM, and 10 were affected by MWA.
Objective: This study aimed to compute phase synchronization of the alpha band from a multichannel electroencephalogram (EEG) recorded under repetitive flash stimulation from migraine patients without aura. This allowed examination of ongoing EEG activity during visual stimulation in the pain-free phase of migraine.
Methods: Flash stimuli at frequencies of 3, 6, 9, 12, 15, 18, 21, 24, and 27 Hz were delivered to 15 migraine patients without aura and 15 controls, with the EEG recorded from 18 scalp electrodes, referred to the linked earlobes.
The aim of this study was to compare the properties of the nociceptive system in eight migraine without aura patients in the pain-free phase with 10 healthy controls, by evaluating the topography and the source of the CO2 laser-evoked potentials (LEPs) obtained by the right supraorbital skin, during and after capsaicin topical application. In healthy subjects the acute cutaneous pain induced by capsaicin reduced the amplitude of the vertex LEPs and induced a posterior shifting of the P2 wave dipolar source within the anterior cingulate cortex. These functional changes seemed significantly reduced in migraine patients, for a disturbed pattern of pain modulation at the cortical level, which may subtend the onset and persistence of migraine.
View Article and Find Full Text PDFObjective: The aim of this study was to perform further evaluation of laser-evoked potentials (LEPs) during migraine attacks using multichannel recording and topographic analysis. Specifically, this study aimed to confirm the pattern previously observed in acute migraine, while also defining the components of LEPs that are mainly modified during headache, as well as the correlation between features of LEPs and clinical variables. In addition, we aimed to conduct a dipolar source analysis of the main LEP waves in migraine patients to check the variability in the source location of LEPs during acute migraine.
View Article and Find Full Text PDFIn migraineurs nitroglycerin (NTG) induces severe delayed headache, resembling spontaneous migraine attacks. The aim of the present study was to evaluate NTG laser evoked potentials (LEP) features amplitude and pain sensation to laser stimuli during NTG-induced headache. Nine patients were selected.
View Article and Find Full Text PDFPrevious studies have revealed that migraine patients display an increased photic driving to flash stimuli in the medium frequency range. The aim of this study was to perform a topographic analysis of steady-state visual evoked potentials (SVEPs) in the low frequency range (3-9 Hz), evaluating the temporal behaviour of the F1 amplitude by investigating habituation and variability phenomena. The main component of SVEPs, the F1, demonstrated an increased amplitude in several channels at 3 Hz.
View Article and Find Full Text PDFCurrent opinion concerning the pathophysiology of tension-type headache (TTH) and its related pericranial muscle tenderness proposes a primary role of central sensitization at the level of dorsalhorn/trigeminal nucleus as well as the supraspinal level. Investigation of these phenomena can be conducted using laser-evoked potentials (LEPs), which are objective and quantitative neurophysiological tools for the assessment of pain perception. In the present study we examined features of LEPs, as well as cutaneous heat-pain thresholds to laser stimulation, in relation to the tenderness of pericranial muscles in chronic TTH resulting from pericranial muscle disorder, during a pain-free phase.
View Article and Find Full Text PDFThe aim of the study was to evaluate the effects of transcutaneous electric nerve stimulation (TENS) on CO(2) laser evoked potentials (LEPs) in 16 normal subjects. The volar side of the forearm was stimulated by 10 Hz TENS in eight subjects and by 100 Hz TENS in the remainder; the skin of the forearm was stimulated by CO(2) laser and the LEPs were recorded in basal conditions and soon after and 15 min after TENS. Both low and high frequency TENS significantly reduced the subjective rating of heat stimuli and the LEPs amplitude, although high frequency TENS appeared more efficacious.
View Article and Find Full Text PDFThe modulation of trigeminal reflex excitability in migraine patients was evaluated during the asymptomatic phase by studying the effects of attention, habituation and preconditioning stimulus on the R2 and R3 components of the blink reflex (BR). Fifty patients suffering from migraine without aura, 20 affected by migraine with aura and 35 sex- and age-matched controls were selected. In subgroups of migraine with-aura and without-aura patients, and normal controls, the blink reflex was elicited during different cognitive situations: (a) spontaneous mental activity; (b) stimulus anticipation; (c) recognition of target numbers.
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