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1.
Biomed Eng Online ; 23(1): 91, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39252062

ABSTRACT

BACKGROUND: Sarcopenia is a muscle disorder causing a progressive reduction of muscle mass and strength, but the mechanism of its manifestation is still partially unknown. The three main parameters to assess are: muscle strength, muscle volume or quality and low physical performance. There is not a definitive approach to assess the musculoskeletal condition of frail population and often the available tests to be performed in those clinical bedridden patients is reduced because of physical impairments. In this paper, we propose a novel instrumental multi-domain and non-invasive approach during a well-defined protocol of measurements for overcoming these limitations. A group of 28 bedridden elder people, subjected to surgery after hip fracture, was asked to perform voluntary isometric contractions at the 80% of their maximum voluntary contraction with the non-injured leg. The sensor employed before and/or during the exercise were: ultrasound to determine the muscle architecture (vastus lateralis); force acquisition with a load cell placed on the chair, giving an indication of the muscle strength; surface electromyography (EMG) for monitoring muscular electrical activity; time-domain (TD) near-infrared spectroscopy (NIRS) for evaluating muscle oxidative metabolism. RESULTS: A personalized "report card" for each subject was created. It includes: the force diagram (both instantaneous and cumulative, expected and measured); the EMG-force diagram for a comparison between EMG derived median frequency and measured force; two graphs related to the hemodynamic parameters for muscle oxidative metabolism evaluation, i.e., oxy-, deoxy-, total-hemoglobin and tissue oxygen saturation for the whole exercise period. A table with the absolute values of the previous hemodynamic parameters during the rest and the ultrasound related parameters are also included. CONCLUSIONS: In this work, we present the union of protocols, multi-domain sensors and parameters for the evaluation of the musculoskeletal condition. The novelties are the use of sensors of different nature, i.e., force, electrical and optical, together with a new way to visualize and combine the results, by means of a concise, exhaustive and personalized medical report card for each patient. This assessment, totally non-invasive, is focused on a bedridden population, but can be extended to the monitoring of rehabilitation progresses or of the training of athletes.


Subject(s)
Electromyography , Humans , Aged , Male , Female , Precision Medicine , Aged, 80 and over , Frail Elderly , Spectroscopy, Near-Infrared , Muscle Strength , Muscle, Skeletal/diagnostic imaging , Isometric Contraction , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods
2.
Adv Exp Med Biol ; 1438: 149-152, 2023.
Article in English | MEDLINE | ID: mdl-37845453

ABSTRACT

Long periods of bed rest for elderly population, due to a femur fracture event, can cause a deterioration in the muscular capacity. Therefore, monitoring of the muscle oxidative capacity in this fragile population is necessary to define the muscular oxidative metabolism state before and after a rehabilitation period. The time-domain near-infrared spectroscopy (TD-NIRS) technique enables the absolute values to be calculated for hemodynamic parameters such as oxy- (O2Hb), deoxy- (HHb), total- (tHb) haemoglobin, and tissue oxygen saturation (SO2) of the muscular tissue. In this work, we have characterized vastus lateralis muscle hemodynamics during a baseline period at two different time points: after the surgery (PRE) and after 15 days of rehabilitation (POST). The mean values for the absolute values of the hemodynamic parameters were: O2Hb_PRE = 49.1 ± 14.1 µM; O2Hb_POST = 47.1 ± 13.4 µM; HHb_PRE = 28.3 ± 10.3 µM; HHb_POST = 26.7 ± 9.9 µM; tHb_PRE = 77.3 ± 23.6 µM; tHb_POST = 73.8 ± 21.4 µM; SO2_PRE = 63.9 ± 4.0% and SO2_POST = 64.9 ± 5.6%. The hemodynamic parameters did not show significant differences at both group and single subject level. These results suggest that for this kind of population, the baseline of the hemodynamic parameters is not the best one to consider to assess the rehabilitation progresses in terms of muscular oxidative metabolism.


Subject(s)
Hemoglobins , Oxygen , Aged , Humans , Oxygen/metabolism , Hemoglobins/metabolism , Hemodynamics , Quadriceps Muscle/metabolism , Spectroscopy, Near-Infrared/methods , Muscle, Skeletal/metabolism , Oxygen Consumption/physiology
3.
Brain Topogr ; 28(6): 915-25, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25253050

ABSTRACT

Multimodal human brain mapping has been proposed as an integrated approach capable of improving the recognition of the cortical correlates of specific neurological functions. We used simultaneous EEG-fMRI (functional magnetic resonance imaging) and EEG-TD-fNIRS (time domain functional near-infrared spectroscopy) recordings to compare different hemodynamic methods with changes in EEG in ten patients with progressive myoclonic epilepsy and 12 healthy controls. We evaluated O2Hb, HHb and Blood oxygen level-dependent (BOLD) changes and event-related desynchronization/synchronization (ERD/ERS) in the α and ß bands of all of the subjects while they performed a simple motor task. The general linear model was used to obtain comparable fMRI and TD-fNIRS activation maps. We also analyzed cortical thickness in order to evaluate any structural changes. In the patients, the TD-NIRS and fMRI data significantly correlated and showed a significant lessening of the increase in O2Hb and the decrease in BOLD. The post-movement ß rebound was minimal or absent in patients. Cortical thickness was moderately reduced in the motor area of the patients and correlated with the reduction in the hemodynamic signals. The fMRI and TD-NIRS results were consistent, significantly correlated and showed smaller hemodynamic changes in the patients. This finding may be partially attributable to mild cortical thickening. However, cortical hyperexcitability, which is known to generate myoclonic jerks and probably accounts for the lack of EEG ß-ERS, did not reflect any increased energy requirement. We hypothesize that this is due to a loss of inhibitory neuronal components that typically fire at high frequencies.


Subject(s)
Brain Mapping , Cerebral Cortex/blood supply , Cerebral Cortex/physiopathology , Corticomedial Nuclear Complex/physiopathology , Hand/innervation , Movement , Adult , Corticomedial Nuclear Complex/pathology , Electroencephalography/methods , Female , Functional Laterality/physiology , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Oxygen/blood , Spectroscopy, Near-Infrared , Time Factors , Young Adult
4.
Clin Neurophysiol ; 159: 56-65, 2024 03.
Article in English | MEDLINE | ID: mdl-38335766

ABSTRACT

OBJECTIVE: Investigate sleep and temporal lobe epilepsy (TLE) effects on brain networks derived from electroencephalography (EEG). METHODS: High-density EEG was recorded during non-rapid eye movement (NREM) sleep stage 2 (N2) and wakefulness in 23 patients and healthy controls (HC). Epochs without epileptic discharges were source-reconstructed in 72 brain regions and connectivity was estimated. We calculated network integration and segregation at global (global efficiency, GE; average clustering coefficient, avgCC) and hemispheric level. These were compared between groups across frequency bands and correlated with the individual proportion of wakefulness- or sleep-related seizures. RESULTS: At the global level, patients had higher delta GE, delta avgCC and theta avgCC than controls, irrespective of the vigilance state. During wakefulness, theta GE of patients was higher than controls and, for patients, theta GE during wakefulness was higher than during N2. Wake-to-sleep differences in TLE were notable only in the ipsilateral hemisphere. Only measures from wakefulness recordings correlated with the proportion of wakefulness- or sleep-related seizures. CONCLUSIONS: TLE network alterations are more prominent during wakefulness and at lower frequencies. Increased integration and segregation suggest a pathological 'small world' configuration with a possible inhibitory role. SIGNIFICANCE: Network alterations in TLE occur and are easier to detect during wakefulness.


Subject(s)
Epilepsy, Reflex , Epilepsy, Temporal Lobe , Humans , Epilepsy, Temporal Lobe/diagnosis , Eye Movements , Wakefulness , Sleep , Seizures
5.
Clin Neurophysiol ; 153: 1-10, 2023 09.
Article in English | MEDLINE | ID: mdl-37364402

ABSTRACT

OBJECTIVE: Structure-function coupling remains largely unknown in brain disorders. We studied this coupling during interictal epileptic discharges (IEDs), using graph signal processing in temporal lobe epilepsy (TLE). METHODS: We decomposed IEDs of 17 patients on spatial maps, i.e. network harmonics, extracted from a structural connectome. Harmonics were split in smooth maps (long-range interactions reflecting integration) and coarse maps (short-range interactions reflecting segregation) and were used to reconstruct the part of the signal coupled (Xc) and decoupled (Xd) from the structure, respectively. We analysed how Xc and Xd embed the IED energy over time, at global and regional level. RESULTS: For Xc, the energy was smaller than for Xd before the IED onset (p < .001), but became larger around the first IED peak (p < .05, cluster 2, C2). Locally, the ipsilateral mesial regions were significantly coupled to the structure over the whole epoch. The ipsilateral hippocampus increased its coupling during C2 (p < .01). CONCLUSIONS: At whole-brain level, segregation gives way to integrative processes during the IED. Locally, brain regions commonly involved in the TLE epileptogenic network increase their reliance on long-range couplings during IED (C2). SIGNIFICANCE: In TLE, integration mechanisms prevail during the IED and are localized in the ipsilateral mesial temporal regions.


Subject(s)
Epilepsy, Temporal Lobe , Epilepsy , Humans , Electroencephalography , Temporal Lobe , Brain , Magnetic Resonance Imaging
6.
Opt Express ; 20(1): 283-90, 2012 Jan 02.
Article in English | MEDLINE | ID: mdl-22274351

ABSTRACT

We report results of the proof-of-principle tests of a novel non-contact tissue imaging system. The system utilizes a quasi-null source-detector separation approach for time-domain near-infrared spectroscopy, taking advantage of an innovative state-of-the-art fast-gated single photon counting detector. Measurements on phantoms demonstrate the feasibility of the non-contact approach for the detection of optically absorbing perturbations buried up to a few centimeters beneath the surface of a tissue-like turbid medium. The measured depth sensitivity and spatial resolution of the new system are close to the values predicted by Monte Carlo simulations for the inhomogeneous medium and an ideal fast-gated detector, thus proving the feasibility of the non-contact approach for high density diffuse reflectance measurements on tissue. Potential applications of the system are also discussed.


Subject(s)
Image Enhancement/instrumentation , Microscopy/instrumentation , Nephelometry and Turbidimetry/instrumentation , Photometry/instrumentation , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity
7.
Acta Anaesthesiol Scand ; 56(1): 66-75, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22092037

ABSTRACT

BACKGROUND: Video-assisted thoracoscopic extended thymectomy (VATET) is well established in the treatment of myasthenia gravis; however, patient selection remains controversial. Perioperative management protocol is lacking, and concerns regarding post-operative myasthenic crisis still remain. We performed a retrospective observational study evaluating the impact of the introduction of a protocol in the perioperative management of patients with myasthenia gravis who underwent VATET. METHODS: The perioperative management protocol was developed by a team of neurologists and anesthesiologists who reviewed the literature and their previous experience on myasthenia gravis patients. Respiratory, clinical, and neurological patient features were included in the protocol evaluation. A retrospective review of patients who underwent VATET before and after introduction to the protocol was finally performed. RESULTS: The medical records of 66 patients (pre-protocol group) and 44 patients (protocol group) were available for the study. In the pre-protocol group, 17 patients (26%) were admitted to intensive care unit (ICU) during the post-operative period, while three patients (6.8%) of the protocol group met the criteria for ICU post-operative admission. This resulted in a reduction of 73.5% of patients admitted to ICU (P = 0.023) and in an 80% (P = 0.002) reduction of the use neuromuscular blocking agents. Two post-operative myasthenic crises preceded by bulbar symptoms (1.8%) were identified in the pre-protocol group patients. CONCLUSIONS: Although the application of our protocol results in a substantial reduction in the recovery of patients in the ICU and in hospital costs, there was no substantial difference in mortality and morbidity between patients admitted to the surgical ward or to ICU.


Subject(s)
Myasthenia Gravis/therapy , Perioperative Care , Adolescent , Adult , Aged , Anesthesia , Child , Clinical Protocols , Cohort Studies , Cost-Benefit Analysis , Critical Care , Female , Hospital Costs , Humans , Male , Middle Aged , Myasthenia Gravis/diagnosis , Myasthenia Gravis/economics , Neurologic Examination , Patient Selection , Perioperative Care/economics , Postoperative Care , Postoperative Complications/diagnosis , Postoperative Complications/epidemiology , Postoperative Complications/mortality , Preoperative Care , Respiratory Mechanics , Treatment Outcome , Young Adult
8.
J Biomech Eng ; 134(3): 031003, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22482683

ABSTRACT

An experimental program has been carried out in order to investigate the mechanical behavior of porcine corneas. We report the results of inflation tests on the whole cornea and uniaxial tests on excised corneal strips, performed on 51 fresh porcine eyes. Uniaxial tests have been performed on specimens cut from previously inflated corneas. The cornea behavior is characterized by means of elastic stiffness, measured on both average pressure-apex displacement and average uniaxial stress-strain curves; and by means of transversal contraction coefficient, peak stress, and failure stress measured on uniaxial stress-strain curves. Uniaxial tests performed on excised strips allowed to measure the anisotropy in the corneal stiffness and to compare the stiffness of the cornea with the one of the sclera. Viscous properties of the cornea have been obtained through uniaxial relaxation curves on excised corneal strips. The relevant geometrical parameters have been measured and, with the aid of the elastic thin shell theory, a stress-strain curve has been derived from the average inflation test data and compared with similar data available in the literature. The experimental system has been developed in view of future applications to the mechanical testing of both porcine and human corneas.


Subject(s)
Cornea , Materials Testing/methods , Mechanical Phenomena , Swine , Animals , Biomechanical Phenomena , Cattle , Humans , Materials Testing/instrumentation , Pressure , Rabbits , Stress, Mechanical , Tensile Strength
9.
Radiol Med ; 117(1): 19-28, 2012 Feb.
Article in English, Italian | MEDLINE | ID: mdl-21744250

ABSTRACT

PURPOSE: Anderson-Fabry disease is a multisystemic disorder of lipid metabolism secondary to X-chromosome alterations and is frequently associated with cardiac manifestations such as left ventricular (LV) hypertrophy, gradually leading to an alteration in cardiac performance. The purpose of this study was to monitor, using magnetic resonance imaging (MRI), any changes produced by enzyme replacement therapy with agalsidase beta at the cardiac level in patients with Anderson-Fabry disease. MATERIALS AND METHODS: Sixteen (ten men, six women) patients with genetically confirmed Anderson-Fabry disease underwent cardiac MRI before starting enzyme replacement therapy (baseline study) and after 48 months of treatment with agalsidase beta at the dose of 1 mg/kg (follow-up study). RESULTS: After 48 months of treatment, a significant reduction in LV mass and wall thickness was observed: 187±59 g vs. 149±44 g, and 16±3 mm vs. 13±3 mm, respectively. A significant reduction in T2 relaxation time was noted at the level of the interventricular septum (81±3 ms vs. 67±7 ms), at the apical level (80±8 ms vs. 63±6 ms) and at the level of the lateral wall (82±8 ms vs. 63±10 ms) (p<0.05). No significant variation was observed in ejection fraction between the two studies (65±3% vs. 64±2%; p>0.05) (mean bias 1.0); however, an improvement was noted in the New York Heart Association (NYHA) class of the majority of patients (12/16) (p<0.05). CONCLUSIONS: In patients with Anderson-Fabry disease undergoing enzyme replacement therapy with agalsidase beta, MRI documented a significant reduction in myocardial T2 relaxation time, a significant decrease in maximal myocardial thickness and in total LV mass. MRI did not reveal significant improvements in LV global systolic function; however, improvement in NYHA functional class was noted, consistent with improved diastolic function.


Subject(s)
Enzyme Replacement Therapy/methods , Fabry Disease/drug therapy , Fabry Disease/physiopathology , Heart Diseases/diagnosis , Heart Diseases/physiopathology , Isoenzymes/therapeutic use , Magnetic Resonance Imaging, Cine/methods , alpha-Galactosidase/therapeutic use , Adult , Female , Humans , Male , Risk Factors , Vectorcardiography
11.
Sci Rep ; 11(1): 13567, 2021 06 30.
Article in English | MEDLINE | ID: mdl-34193904

ABSTRACT

In this paper, we used time-domain functional near infrared spectroscopy (TD-fNIRS) to evaluate the haemodynamic response function (HRF) in the occipital cortex following visual stimulation in glaucomatous eyes as compared to healthy eyes. A total of 98 subjects were enrolled in the study and clinically classified as healthy subjects, glaucoma patients (primary open-angle glaucoma) and mixed subjects (i.e. with a different classification for the two eyes). After quality check data were used from HRF of 73 healthy and 62 glaucomatous eyes. The amplitudes of the oxygenated and deoxygenated haemoglobin concentrations, together with their latencies with respect to the stimulus onset, were estimated by fitting their time course with a canonical HRF. Statistical analysis showed that the amplitudes of both haemodynamic parameters show a significant association with the pathology and a significant discriminating ability, while no significant result was found for latencies. Overall, our findings together with the ease of use and noninvasiveness of TD-NIRS, make this technique a promising candidate as a supporting tool for a better evaluation of the glaucoma pathology.


Subject(s)
Glaucoma, Open-Angle , Hemodynamics , Hemoglobins/metabolism , Photic Stimulation , Adult , Female , Glaucoma, Open-Angle/metabolism , Glaucoma, Open-Angle/physiopathology , Humans , Male , Middle Aged , Spectrophotometry, Infrared
12.
Biomed Opt Express ; 11(12): 7357-7375, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-33409002

ABSTRACT

The effect of sustained fatigue during an upper limb isometric exercise is presented to investigate a group of healthy subjects with simultaneous time-domain (TD) NIRS and surface electromyography (sEMG) recordings on the deltoid lateralis muscle. The aim of the work was to understand which TD-NIRS parameters can be used as descriptors for sustained muscular fatigue, focusing on the slow phase of this process and using median frequency (MF) computed from sEMG as gold standard measure. It was found that oxygen saturation and deoxy-hemoglobin are slightly better descriptors of sustained fatigue, than oxy-hemoglobin, since they showed a higher correlation with MF, while total-hemoglobin correlation with MF was lower.

13.
Neuroimage ; 46(3): 834-43, 2009 Jul 01.
Article in English | MEDLINE | ID: mdl-19408351

ABSTRACT

Simultaneous EEG-fMRI acquisitions in patients with epilepsy often reveal distributed patterns of Blood Oxygen Level Dependant (BOLD) change correlated with epileptiform discharges. We investigated if electrical source imaging (ESI) performed on the interictal epileptiform discharges (IED) acquired during fMRI acquisition could be used to study the dynamics of the networks identified by the BOLD effect, thereby avoiding the limitations of combining results from separate recordings. Nine selected patients (13 IED types identified) with focal epilepsy underwent EEG-fMRI. Statistical analysis was performed using SPM5 to create BOLD maps. ESI was performed on the IED recorded during fMRI acquisition using a realistic head model (SMAC) and a distributed linear inverse solution (LAURA). ESI could not be performed in one case. In 10/12 remaining studies, ESI at IED onset (ESIo) was anatomically close to one BOLD cluster. Interestingly, ESIo was closest to the positive BOLD cluster with maximal statistical significance in only 4/12 cases and closest to negative BOLD responses in 4/12 cases. Very small BOLD clusters could also have clinical relevance in some cases. ESI at later time frame (ESIp) showed propagation to remote sources co-localised with other BOLD clusters in half of cases. In concordant cases, the distance between maxima of ESI and the closest EEG-fMRI cluster was less than 33 mm, in agreement with previous studies. We conclude that simultaneous ESI and EEG-fMRI analysis may be able to distinguish areas of BOLD response related to initiation of IED from propagation areas. This combination provides new opportunities for investigating epileptic networks.


Subject(s)
Action Potentials , Diagnosis, Computer-Assisted/methods , Electroencephalography/methods , Epilepsy/diagnosis , Epilepsy/physiopathology , Magnetic Resonance Imaging/methods , Nerve Net/physiopathology , Adult , Brain Mapping/methods , Female , Humans , Male , Middle Aged , Pediatrics/methods , Reproducibility of Results , Sensitivity and Specificity , Young Adult
14.
Eur J Clin Invest ; 39(8): 664-70, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19490065

ABSTRACT

BACKGROUND: Reduced systolic reserve on effort may be present in subjects with hypertension but no evidence of hypertensive cardiomyopathy. We assessed the determinants of abnormal cardiac performance during exercise in hypertensive patients without left ventricular hypertrophy. MATERIALS AND METHODS: Thirty-five newly diagnosed, never-treated-earlier hypertensive patients without definite indication for left ventricular hypertrophy at echocardiography underwent radionuclide ambulatory monitoring of left ventricular function at rest and during upright bicycle exercise testing. RESULTS: The patients were classified into two groups according to their ejection fraction response to exercise. In 21 patients (group 1), the ejection fraction increased > or = 5% with exercise and in 14 patients (group 2), the ejection fraction either increased < 5% or decreased with exercise. Patients of group 1 had lower peak filling rate at rest and less augmentation in end-diastolic volume during exercise (both P < 0.01) when compared with patients of group 2. A significant relationship between the magnitude of change in ejection fraction with exercise and both peak filling rate at rest (r = 0.58, P < 0.01) and exercise-induced change in end-diastolic volume (r = 0.45, P < 0.01) was found. CONCLUSIONS: In newly diagnosed, never-treated-earlier hypertensive subjects with no evidence of hypertensive cardiomyopathy, the cardiac response to exercise is dependent on adequate diastolic filling volume to maintain systolic performance.


Subject(s)
Diastole/physiology , Heart/physiopathology , Hypertension/physiopathology , Stroke Volume/physiology , Ventricular Function, Left/physiology , Angiography , Exercise Test , Exercise Tolerance , Female , Heart/diagnostic imaging , Humans , Hypertension/diagnostic imaging , Male , Middle Aged , Radionuclide Imaging
15.
Appl Spectrosc ; 63(1): 48-56, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19146718

ABSTRACT

This paper discusses the spectral distortions occurring when time-resolved spectroscopy of diffusive media is performed illuminating with a wide bandpass. It is shown that the spectral region within the bandpass that exhibits the lowest absorption will dominate the resulting time-resolved curve, leading to significant underestimations of absorption as well as distortions in the spectral shape (including shifts in peak positions). Due to the nonlinear behavior of absorption, this effect becomes even more pronounced when including longer and longer photon path lengths. First, a theoretical treatment of the problem is given, and then the distortion is described by time-resolved reflectance simulations and experimental measurements of lipid and water samples. A spectrally constrained data analysis is proposed that takes into account the spectrum of the light injected into the sample, used to overcome the distortion and improve the accuracy of the estimation of chromophore concentrations from absorption spectra. Measurements on a lipid sample show a reduction of the error from 30% to 6%.

16.
Eur J Clin Invest ; 38(12): 910-7, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19021715

ABSTRACT

BACKGROUND: Fatigability and dyspnoea on effort are present in many patients with Fabry's disease. We assessed the determinants of cardiac performance during exercise in patients with Fabry's disease and preserved left ventricular ejection fraction at rest. MATERIALS AND METHODS: Sixteen patients with Fabry's disease and 16 control subjects underwent radionuclide angiography at rest and during exercise, tissue Doppler echocardiography and magnetic resonance imaging at rest. RESULTS: The exercise-induced change in stroke volume was +25 +/- 14% in controls and +5.8 +/- 19% in patients with Fabry's disease (P < 0.001). In 10 patients (group 1), the stroke volume increased (+19 +/- 10%), and in 6 patients (group 2) it decreased (-16 +/- 9%) with exercise. Patients of group 2 were older, had worse renal function, higher left ventricular mass and impaired diastolic function compared to group 1. The abnormal stroke volume response to exercise in group 2 was associated with a decrease in end-diastolic volume (P < 0.001) and a lack of reduction of end-systolic volume (P < 0.01) compared with both controls and group 1. The ratio of peak early-diastolic velocity from mitral filling to peak early-diastolic mitral annulus velocity was the only independent predictor of exercise-induced change in stroke volume (B -0.44; SE 0.119; beta-0.70; P < 0.005). CONCLUSIONS: The majority of patients with Fabry's disease were able to augment stroke volume during exercise by increasing end-diastolic volume, whereas patients with more advanced cardiac involvement may experience the inability to increase cardiac output by the Frank Starling mechanism.


Subject(s)
Cardiac Output, Low/physiopathology , Exercise Test , Exercise Tolerance/physiology , Fabry Disease/physiopathology , Stroke Volume/physiology , Ventricular Function, Left/physiology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Fabry Disease/genetics , Female , Heart , Humans , Male , Middle Aged , Prospective Studies
17.
Neuropsychologia ; 45(4): 644-53, 2007 Mar 02.
Article in English | MEDLINE | ID: mdl-17049953

ABSTRACT

The exquisite sensitivity of the human visual system to form-from-motion (FfM) cues is well documented. However, identifying the neural correlates of this sensitivity has proven difficult, particularly determining the respective contributions of different motion areas in extrastriate visual cortex. Here we measured visual FfM perception and more elementary visual motion (VM) perception in a group of 32 patients suffering from acute posterior brain damage, and performed MRI-based lesion analysis. Our results suggest that severe FfM perception deficits without an associated deficit of VM perception are due to damage to ventral occipito-temporal cortex (VOT), whereas associated deficits of FfM and VM perception are due to damage either in proximity to area MT+/V5 or an area including lateral occipital complex (LOC) and VOT. These data suggest the existence of at least three functionally and anatomically distinct regions in human visual cortex that process FfM signals.


Subject(s)
Discrimination Learning/physiology , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Motion Perception/physiology , Pattern Recognition, Visual/physiology , Visual Cortex/physiopathology , Visual Pathways/physiology , Adult , Aged , Aged, 80 and over , Brain Damage, Chronic/diagnosis , Brain Damage, Chronic/physiopathology , Dominance, Cerebral/physiology , Female , Field Dependence-Independence , Humans , Male , Middle Aged , Occipital Lobe/physiopathology , Orientation/physiology , Parietal Lobe/physiopathology , Reference Values , Sensory Thresholds/physiology , Stroke/diagnosis , Stroke/physiopathology , Temporal Lobe/physiopathology
18.
J Endocrinol Invest ; 30(6): 497-506, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17646725

ABSTRACT

This analytical, observational, retrospective, case-control study was designed to describe clinical presentation, biochemical disease severity, presence, and severity of metabolic and cardiovascular complications in patients diagnosed as having acromegaly at 60 yr or older (no.=57) as compared to sex- and age-matched healthy controls. Patients and controls underwent a complete endocrine, metabolic, and cardiovascular check-up. The age at diagnosis was equally distributed between 60 to 75 yr while only a minority of the patients (5.3%) was diagnosed after 75 yr. Median GH and IGF-I levels were 15 microg/l and 557 microg/l. The prevalence of microadenomas, enclosed macroadenomas, and extrasellar/invasive macroadenomas was 30%, 49%, and 21%, respectively. All patients had joint complaints and goiter (euthyroid in 65% and pre-toxic/toxic in 35%), 82% had hypertension, 58% diabetes and 54% had both. As compared to controls, a higher number of patients were receiving treatment with anti-arrhythmiacs (p=0.033), anti-aggregants (p=0.013), levothyroxine (p=0.015), and metformin (p=0.022). Nevertheless, the patients had higher systolic and diastolic blood pressure, heart rate, left ventricular mass index, lipids, glucose and insulin levels as well as percent function of beta cells than controls. In conclusion, the high prevalence of systemic complications makes elderly acromegalics more susceptible than controls to cardiovascular events. We suggest that an accurate clinical check-up and, possibly, a more aggressive treatment of hypertension and diabetes are required in elderly acromegalics.


Subject(s)
Acromegaly , Cardiomyopathies , Acromegaly/complications , Acromegaly/metabolism , Acromegaly/physiopathology , Age of Onset , Aged , Aged, 80 and over , Cardiomyopathies/etiology , Cardiomyopathies/metabolism , Cardiomyopathies/physiopathology , Cardiovascular Physiological Phenomena , Case-Control Studies , Female , Glucose/metabolism , Human Growth Hormone/blood , Humans , Insulin-Like Growth Factor I/metabolism , Male , Middle Aged , Retrospective Studies , Risk Factors
19.
Epileptic Disord ; 9(1): 20-31, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17307708

ABSTRACT

UNLABELLED: Multiple structural and functional imaging modalities are available to localize the epileptogenic focus. In pre-surgical evaluation of children with pharmacoresistant epilepsy, investigations with the maximum yield should be considered in order to reduce the complexity of the workup. OBJECTIVE: To determine the extent to which PET, ictal/interictal SPECT and its co-registration with the patient's MRI contributes to correct localization of the epileptogenic focus, surgical intervention and to the post surgical outcome in paediatric patients. METHODS: The study population included children and adolescents with pharmacoresistant epilepsy (n = 50) who underwent preoperative evaluation, surgery and had postoperative follow-up for at least 12 months. Outcome was measured by postoperative seizure frequency using Engel's classification. RESULTS: Thirty-nine patients (78%) became completely seizure free after surgical intervention. The likelihood to benefit from surgical treatment was significantly higher if localization with more imaging modalities (MRI, PET, SPECT) were concordant with respect to the resected brain area (p < 0.01). Preoperative PET examination provided better localizing information in patients with extratemporal epilepsy and/or dysplastic lesions, whereas SPECT was found to be superior to PET in patients with temporal lobe epilepsy and/or tumors (p < 0.05). No significant difference was noted in the surgical outcome in younger or older age group, in children with or without special education needs. CONCLUSION: In paediatric epilepsy pre-surgical evaluation, the combined use of multiple functional imaging modalities for a precise localisation of the epileptogenic focus is worthwhile for both extratemporal and temporal lobe epilepsy, also when EEG and MRI alone are non-contributive, given the potential benefit of complete postoperative seizure control.


Subject(s)
Epilepsy/diagnosis , Magnetic Resonance Imaging , Positron-Emission Tomography , Tomography, Emission-Computed, Single-Photon , Adolescent , Age Factors , Child , Child, Preschool , Electroencephalography , Epilepsy/pathology , Epilepsy/surgery , Female , Humans , Infant , Male , Preoperative Care , Treatment Outcome , Video Recording
20.
J Clin Endocrinol Metab ; 91(11): 4319-25, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16926253

ABSTRACT

BACKGROUND: Fabry disease (FD) is a genetic disorder caused by lysosomal alpha-galactosidase-A deficiency and is characterized by the systemic accumulation of globotriaosylceramide. All endocrine glands are susceptible to globotriaosylceramide accumulation because of their high vascularization and low cellular proliferation rate. Nevertheless, this endocrine system has never been investigated in detail. OBJECTIVE: We aimed to investigate the function and morphology of the endocrine glands in FD. PATIENTS: The thyroid, gonadal, adrenal, and GH/IGF-I axes were evaluated in 18 FD patients (nine females and nine males, aged 21-64 yr) and 18 sex- and age-matched healthy subjects. STUDY DESIGN: We conducted an observational, analytical, open, prospective study. INTERVENTIONS: Ten of the 18 patients received enzyme replacement therapy (ERT) with recombinant human alpha-galactosidase-A (agalsidase beta) at a dose of 1 mg/kg body weight every 2 wk. RESULTS: FD patients had higher baseline TSH levels than controls (P < 0.01). Three subjects were diagnosed with an early stage of subclinical primary hypothyroidism associated with negative antithyroid antibodies. A history of menses abnormalities, miscarriage, or assisted delivery was found in 89% of FD women. Asthenozoospermia, oligozoospermia, or both were found in all FD men through seminal fluid analysis. FD patients had significantly higher circulating ACTH and lower cortisol levels than controls (P < 0.05). In patients under ERT, a suboptimal cortisol response to the 250-microg ACTH test was found in 10%, and the ACTH-stimulated cortisol peak was significantly correlated to the health status profile (P < 0.05). CONCLUSION: A variety of latent endocrine dysfunctions, including life-threatening conditions, occur in patients with FD. Endocrine dysfunctions are also present in patients already receiving ERT and are in part related to their persistent poor quality of life. An endocrine work-up should be recommended in all FD patients. Adequate monitoring and hormonal therapy, when required, have to be performed in cases of subclinical endocrine dysfunction to avoid life-threatening events.


Subject(s)
Endocrine System Diseases/complications , Endocrine System/physiology , Fabry Disease/complications , Adrenal Gland Diseases/epidemiology , Adult , Case-Control Studies , Comorbidity , Endocrine System Diseases/epidemiology , Fabry Disease/blood , Fabry Disease/metabolism , Female , Gonadal Disorders/epidemiology , Growth Hormone/metabolism , Growth Hormone/physiology , Humans , Insulin-Like Growth Factor I/metabolism , Insulin-Like Growth Factor I/physiology , Male , Middle Aged , Prospective Studies , Thyroid Diseases/epidemiology
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