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C Cortina

Publications and source records attributed to C Cortina.

14 recordsLinked to original sources
PubMed2006

Support vector analysis of color-Doppler images: a new approach for estimating indices of left ventricular function.

Reliable noninvasive estimators of global left ventricular (LV) chamber function remain unavailable. We have previously demonstrated a potential relationship between color-Doppler M-mode (CDMM) images and two basic indices of LV function: peak-systolic elastance (Emax) and the time-constant of LV relaxation (tau). Thus, we hypothesized that these two indices could be estimated noninvasively by adequate postprocessing of CDMM recordings. A semiparametric regression (SR) version of support vector machine (SVM) is here proposed for building a blind model, capable of analyzing CDMM images automatically, as well as complementary clinical information. Simultaneous invasive and Doppler tracings were obtained in nine mini-pigs in a high-fidelity experimental setup. The model was developed using a test and validation leave-one-out design. Reasonably acceptable prediction accuracy was obtained for both Emax (intraclass correlation coefficient Ric, = 0.81) and tau (Ric, = 0.61). For the first time, a quantitative, noninvasive estimation of cardiovascular indices is addressed by processing Doppler-echocardiography recordings using a learning-from-samples method.

Algorithms↗
PubMed2005

Effects of angiotensin converting enzyme inhibitors in hypertensive patients with aortic valve stenosis: a drug withdrawal study.

OBJECTIVE: To determine the effects of angiotensin converting enzyme (ACE) inhibitors in hypertensive patients with aortic valve stenosis (AS). DESIGN: Observational, drug withdrawal, single blinded study, with randomisation of the order of tests. SETTING: Hypertension and asymptomatic AS. PATIENTS AND INTERVENTIONS: 20 patients (aged 73 (9) years, valve area 0.7 (0.3) cm2, left ventricular ejection fraction > or = 45%) were enrolled. Each patient underwent two sets of tests (with and without taking the drug), each of which included clinical evaluation, Doppler echocardiogram, and symptom limited exercise echocardiography. MAIN OUTCOME MEASURES: Functional and haemodynamic variables while taking and not taking ACE inhibitors. RESULTS: Drug intervention induced no change in patients' subjective functional class. While taking ACE inhibitors, patients had a lower systolic blood pressure (140 (18) mm Hg with ACE inhibitors v 159 (12) mm Hg without ACE inhibitors, p = 0.02), a higher mean pressure gradient (34 (15) mm Hg v 28 (18) mm Hg, p = 0.037), and a higher left ventricular stroke work loss (19 (6)% v 14 (10)%, p = 0.009). Other baseline functional and haemodynamic parameters were unmodified. Five patients had an abnormal blood pressure response during one of the exercise tests (two patients while taking the drug and three patients while not taking the drug). When taking ACE inhibitors, patients had a higher stroke volume at peak stress (59 (11) ml v 54 (25) ml, p = 0.046). All other stress variables remained constant. CONCLUSIONS: In AS, the afterload relief caused by ACE inhibitors is blunted by a parallel increase in the pressure gradient. However, ACE inhibitors favourably affect stress haemodynamic function in most hypertensive patients with AS and should not be discontinued.

Aged↗
PubMed2003

[Importance of the clinical-radiological complementarity in superficial cerebral siderosis].

We report two cases of superficial siderosis of central nervous system. In one case it was idiopathic and in the other secondary to an unidentified subarachnoid hemorrhage. The symptoms that characterized the clinical picture of both were gait disturbance and hypoacusis. The MRI study showed a superficial rim of hypointensity that covered the cerebellum and brainstem, and extended along the cranial nerves and the brain surface. The findings were clearer in the T2 spin echo series. Due to the high sensitivity for hemosiderin deposits, MRI made it possible to make the final diagnosis of this rare disease.

Aged↗
PubMed1999

[Symptomatic paroxysmal dystonia (non-kinesigenic forms): two new cases].

We report two new cases of symptomatic paroxysmal non-kinesigenic dystonia. The first is a 68-year-old woman with paroxysmal spontaneous dystonic spasms in her right arm lasting 1 minute. They occurred 1-2/day, a few months after a cerebral infarction (left internal capsule and left lenticular nucleus) which occurred 6 years ago. The second is a 30-year-old woman with a 7-year-history of spontaneous dystonic postures (flexion spasms) in her left arm lasting 15 minutes and occurring monthly. In this case an Arnold-Chiari malformation with cervical syringomyelia was discovered.

Adult↗
PubMed1998

[Idiopathic cervical plexopathy].

We describe a 26 year-old woman with cervical plexopathy with damage of left superficial or cutaneous branches, and left cervical sensory dorsal rami. Picture began acutely and vanished few days later. We ruled out known etiologies like traumatisms, tumours and surgical and anaesthetic complicated procedures, therefore the patient suffered an idiopathic cervical plexopathy. We hypothesize two possibilities for this clinical picture: an autoimmune reaction or a muscular entrapment.

Acute Disease↗
PubMed1980

Mitochondrial functions in chronic spinal muscular atrophy.

We determined the respiration rate, respiratory control and ADP/O ratios, with different substrates in mitochondria isolated from seven patients with chronic spinal muscular atrophy and compared them with normal human muscle. In all cases studied, a severe alteration of the respiratory control with variable derangement of oxidative phosphorylation was found. Similar findings have been described in other neuromuscular disorders including the so-called "mitochondrial myopathy". We believe that this disturbance of mitochondrial function is non specific and only the hypermetabolic syndrome of Luft could be considered biochemically as a "mitochondrial myopathy", a disorder selectively involving mitochondria of skeletal muscle.

Adolescent↗
PubMedDate not supplied

[Non tumoural cerebral biopsies: an analysis of 50 cases].

OBJECTIVE: Cerebral biopsy is an invasive technique with limited, specific indications in view of the potential risk of complications. PATIENTS AND METHODS: We reviewed a series of 50 cases of biopsies via craniotomy done over a period of 10 years to investigate suspected non tumoural disorders. RESULTS: There was a predominance of space occupying lesions and treatable infections (36%) and of non diagnostic biopsies (40%). There was poor correlation between the initial clinical diagnosis and the histological findings (50 71%). There were no complications. CONCLUSIONS: We conclude that the indications should be better defined and, in view of the satisfactory tolerance of this procedure, the study group should be increased by using other less invasive procedures (stereotaxia).

Biopsy↗
PubMedDate not supplied

[Dementia with frontal lobe atrophy: clinical study from 18 patients with cognitive impairment and frontal lobe involvement detected by structural and functional neuroimaging].

OBJECTIVE: To characterize clinically patients with cognitive impairment and frontal lobe degeneration at neuroimaging. PATIENTS AND METHODS: Patients diagnosed of dementia or mild neurocognitive impairment by DSM IV criteria and neuropsychological tests with frontal lobe atrophy and hipoperfusion detected by computed tomography and single photon emission computed tomography. RESULTS: 18 patients, 5:1 on behalf of women; mean age at onset, 74 years; hereditary for dementia, 38%; mean duration of illness at first testing, 2 years; the most common initial symptoms, memory loss. At initial examination, psychotic or behavioral impairment was found in 61% and parkinsonism in 38%, the commonest cognitive troubles at this moment was the executive function, language and anterograde memory dysfunctions at the same rate. Frontal lobe atrophy and hypoperfusion was found in 100%, temporal in 88% and parietal in 38%. Electroencephalogram was pathological in 33%. The course of the disease was progressive but with fluctuation in 27%. Frontotemporal dementia clinical criteria in 13 patients, 4 of them clinical criteria of dementia with Lewy bodies too, and clinical criteria of Alzheimer s disease in 5.

Aged↗