92 research outputs found
Spread of electrical activity at cortical level after repetitive magnetic stimulation in normal subjects
No full textIn normal subjects, focal repetitive transcranial magnetic stimulation (rTMS) of the hand motor area evokes muscle potentials (MEPs) from muscles in the hand (target muscles) and the arm (non-target muscles). In this study we investigated the mechanisms underlying the spread of MEPs induced by focal rTMS in non-target muscles. rTMS was delivered with a Magstim stimulator and a figure-of-eight coil placed over the first dorsal interosseus (FDI) motor area of the left hemisphere. Trains of 10 stimuli were given at a suprathreshold intensity (120% of motor threshold) and at frequencies of 5, 10 and 20 Hz at rest. Electromyographic (EMG) activity was recorded simultaneously from the FDI (target muscle) and the contralateral biceps muscle and from the FDI muscle ipsilateral to the side of stimulation (nontarget muscle). rTMS delivered in trains to the FDI motor area of the left hemisphere elicited MEPs in the contralateral FDI (target muscle) that gradually increased in amplitude over the course of the train. Focal rTMS trains also induced MEPs in the contralateral biceps (non-target muscle) but did so only after the second or third stimulus; like target-muscle MEPs, in non-target muscle MEPs progressively increased in amplitude during the train. At no frequency did rTMS elicit MEPs in the FDI muscle ipsilateral to the site of stimulation. rTMS left the latency of EMG responses in the FDI and biceps muscles unchanged during the trains of stimuli. The latency of biceps MEPs was longer after rTMS than after a single TMS pulse. In conditioning-test experiments designed to investigate the cortical origin of the spread, a single TMS pulse delivered over the left hemisphere at an interstimulus interval (ISI) of 50, 100 and 150 ms reduced the amplitude of the test MEP evoked by a single TMS pulse delivered over the right hemisphere; and a conditioning rTMS train delivered over the left hemisphere increased the amplitude of the test MEP evoked by a single TMS pulse over the right hemisphere. A conditioning rTMS train delivered over the left hemisphere and paired magnetic shocks (test stimulus) at 3 and 13 ms ISIs over the right hemisphere reduced MEP inhibition at the 3-ms ISI but left the MEP facilitation at 13 ms unchanged. Using a control MEP size matched with that observed after a conditioning contralateral rTMS, we found that paired-pulse inhibition remained unchanged. Yet a single TMS conditioning pulse sufficiently strong to evoke a MEP in the contralateral FDI and biceps muscles simultaneously (as rTMS did) left paired-pulse inhibition unchanged. We conclude that the spread of EMG activity to non-target muscles depends on cortical mechanisms, mainly including changes in the excitability of the interneurones mediating intracortical inhibition
Hemodialysis in patients requiring 131I treatment for thyroid carcinoma.
No full textPurpose: Thyroid malignancies can be treated by surgery followed by ablation of the remnant tissue with I-131. As iodide removal from the body occurs by renal extraction, in patients suffering from end-stage renal disease it is necessary to properly evaluate both timing and method of the extracorporeal treatment.
Methods: We present two patients on regular hemodialysis, admitted in isolation to the Nuclear Medicine Department and treated with I-131 for thyroid carcinoma diagnosed during the check-up for transplantation. Both patients underwent two hemodialysis sessions with a portable machine for CRRT (continuous renal replacement therapy), 24 and 48 hours after the administration of 50 mCi of I-131. The nursing staff were monitored with a dosimeter. Radioactivity of the patients, dialysate and urines were measured during hemodialysis.
Results: The greater reduction was obtained with the first dialysis, but in both patients a further, though shorter, hemodialysis at 48 hours was necessary for reaching a patient's radioactivity compatible with discharge. Radioactivity measured in the dialysate demonstrated the almost total removal of radioiodine by dialysis alone. In both patients, follow-up exams revealed a complete ablation of thyroid tissue, without signs of local recurrence. The dose of radioactivity of the dialysis staff was below allowable limits.
Conclusions: We conclude that a successful reduction of radioactivity, without dispersing its therapeutic efficacy, can be obtained with daily hemodialysis with a CRRT machine in patients in isolation treated with I-131. A therapeutic model is proposed
Imbalance between oxidative stress and antioxidant defence in patients with acute ischemic stroke.
No full textFoFi: The Development of a Handheld Monitoring Device in Predicting Naturally Occurring Forest Fires
No full textForest fires, which are natural or artificial burning of woodlands, negatively affect people and the environment. In the Philippines, Cordillera is one of the hotspots for forest fires, with approximately 122 forest fire incidents. Thus, developing a monitoring device for the early prevention of forest fires would reduce these incidents\u27 frequency. This research aimed to create a handheld prototype device, FoFi, that gathers quantitative data which can be used with the Department of Natural Resources\u27s data science and predictive analytics. Using an Arduino Microcontroller and sensors, the device will collect and send data. Two phases were conducted to create a monitoring prototype device for predicting forest fires. According to the results, the temperature and humidity (DHT-22) sensor showed reliable data since it can detect temperature under normal conditions, having a mean of 30.65°C; also, it precisely recorded the relative humidity with a mean of 7.89%. The Global Positioning System (GPS) module obtained a mean error of 7.251 m, which exhibited accuracy in detecting GPS coordinates. Additionally, the Globe SIM showed efficiency for Global Systems for Mobile (GSM) communication since the mean length of time for sending a message is 5.022 s. On the other hand, the gas sensor (MQ-2) and photoresistor lacks sensitivity when used; thus, a more sensitive sensor is recommended. In conclusion, the handheld device was able to achieve its purpose of monitoring forest fires
Progesterone receptor gene (PROGINS) polymorphism correlates with late onset of migraine
No full textProgesterone influences central neuronal excitability, a key event in migraine pathophysiology. Progesterone receptor gene (PGR) rs1042838 (G/T - Val660Leu) variant is indicative of PROGINS haplotype and associated to a reduced PGR activity. With the aim of investigating whether any type of association existed between this genetic variant and migraine pathophysiology, genotyping was performed in 380 consecutive migraine patients and 185 age-, sex-, and race-ethnicity-matched healthy controls from Interinstitutional Multidisciplinary BioBank (BioBIM) of IRCCS San Raffaele Pisana, Rome, Italy. rs1042838 genotypes did not correlate with demographics or clinical migraine features. However, TT (Leu) genotype was significantly associated with a later age of migraine onset: Patients affected by migraine with aura showed a linear relationship between copy number of the T allele carried by the individual and the age of migraine onset. Our data suggest that the PROGINS PGR polymorphism does not directly predispose to migraine but significantly delays migraine onset probably via a reduction in brain neuronal excitability
O039. Case-control genetic association studies in migraine: a 7-year experience at the Interinstitutional Multidisciplinary Biobank (BioBIM) of IRCCS San Raffaele Pisana
No full textAbstract not availabl
Is SOD2 Ala16Val polymorphism associated with migraine with aura phenotype?
No full textSeveral studies suggest a role of oxidative stress in the physiopathology of migraine, particularly in the form with aura. In a case-control study, we investigated the association between migraine and superoxide dismutase 1 (SOD1) and superoxide dismutase 2 (SOD2) genes in a cohort of 490 consecutive unrelated Caucasian migraineurs (migraine with aura [MwA], n=107; migraine without aura [MwoA], n=246; chronic migraine [CM], n=137) and 246 healthy controls recruited at our Headache and Pain Unit and stored in the Interinstitutional Multidisciplinary BioBank (BioBIM). Migraine phenotype was carefully detailed using face-to-face interviews. We examined polymorphisms of SOD1 gene (A/C substitution-rs2234694) and SOD2 gene (C/T transition-rs4880-Ala16Val). The rs4880 TT (Val/Val) genotype was associated (p=0.042) with the presence of unilateral cranial autonomic symptoms (UAs) in MwA patients. We also found a mild correlation between SOD2 rs4880 genotype and the type of acute migraine treatment (p=0.048) in MwA patients. Our findings suggest that SOD2 is a disease-modifier gene influencing oxidative mechanisms in MwA. These observations lead to the hypothesis that SOD2 polymorphism may cause a defective control of the oxidative phenomena linked to cortical spreading depression, the neurophysiological hallmark of migraine aura, causing an overstimulation of trigeminal neurons and UAs triggering. Antioxid. Redox Signal. 22, 275-279
Prion protein gene M129V polymorphism and variability in age at migraine onset
No full textPrion protein, a sialoglycoprotein with neuroprotective properties on oxidative stress damage, has been related with the mechanisms leading to migraine. In the present case-control study, we investigated the correlation between the common methionine/valine polymorphism at codon 129 within the prion protein gene (PRNP) and migraine. Genotyping of PRNP V129M variant was performed in 384 migraine patients and 185 age-, sex-, and race-ethnicity-matched healthy controls. The frequencies of the PRNP V129M genotype did not differ significantly between migraineurs and controls. The frequencies of 129VV genotype were significantly higher in patients with earlier age at migraine onset. No correlation was found between PRNP 129 genotype and demographics, and other clinical migraine features. Our data suggest that the PRNP 129VV polymorphism is not a direct migraine risk factor but is significantly associated with an earlier onset of the disease. © 2013 American Headache Society
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