Biomedical subjects

F Torres

Publications and source records attributed to F Torres.

At least 91 records · Page 5Linked to original sources

PubMed1992

Longitudinal neurophysiologic studies in a patient with metachromatic leukodystrophy following bone marrow transplantation.

We describe a girl with late infantile metachromatic leukodystrophy. The patient has been followed up with serial neurologic and neurophysiologic examinations for 8 years following bone marrow transplantation, which she underwent when she was 4 3/4 years old. Her older sister died from metachromatic leukodystrophy at the age of 8 years, whereas our patient has retained significant cognitive and motor skills. Serial neurophysiologic studies initially demonstrated continued deterioration after the bone marrow transplantation, but since then, most results have remained stable or improved. Although, to our knowledge, there have been no previous serial studies of metachromatic leukodystrophy, individual case studies suggest that these findings in our patient are very unusual. With the advent of possible treatment for this condition, there is a need for further serial neurophysiologic studies to characterize the natural progression and the possible detection of progression or reversal with treatment.

Action Potentials↗

PubMed1992

[Bradyarrhythmias secondary to the use of ophthalmic timolol. A report of 3 cases].

Three cases of symptomatic bradycardia due to topical ocular timolol administration are reported. Two patients had syncope related to atrioventricular block, and the other one complained of dizziness due to sinus bradycardia. Heart disease was not present in any case, although a right bundle branch block was observed in one patients. A normal sinus rhythm resumed in all patients after discontinuation of timolol.

Aged↗

PubMed1992

[Spontaneous remission in a patient with long-term idiopathic dilated myocardiopathy].

The case of a patient with long-term idiopathic dilated cardiomyopathy, functional class IV, very depressed left ventricular ejection fraction (13%) and history of severe dyspnea for more than four years, who experienced an spontaneous clinical and hemodynamic recovery (functional class I, left ventricular ejection fraction 51%) while being on waiting list for heart transplantation is reported. The patient remains in good clinical condition after a follow-up of two years.

Cardiomyopathy, Dilated↗

PubMed1991

Both cell surface and internalized beta-adrenoceptors are reduced in the failing myocardium.

To study myocardial beta-adrenoceptor internalization in heart failure, we measured beta-adrenoceptor density in the particulate, light vesicle and supernatant fractions of ventricular tissue of dogs with experimental right ventricular failure and sham-operated dogs. Tissue was fractionated by centrifugation, and beta-adrenoceptors were measured by [125I]iodocyanopindolol binding. Compared to sham-operated controls, beta-adrenoceptors were reduced in all fractions of right ventricular tissue from heart failure animals. Thus, the decreased surface (particulate fraction) receptors observed cannot be explained by internalization alone, and must be associated with altered receptor synthesis or degradation.

Animals↗

PubMed1991

[Cough caused by angiotensin-converting enzyme inhibitors. A series of cases collected by spontaneous notification of adverse reactions].

Cough is one of the possible untoward adverse drug effects of angiotensin converting enzyme inhibitors. We describe the available information on 50 cough episodes attributable to captopril and 18 episodes attributable to enalapril reported to the Spanish Drug Surveillance System. Cough represented 37% and 39% of the reports of side effects of captopril and enalapril, respectively. There was a remarkable female predominance among the patients with cough. Cough developed at very low doses (15 mg of captopril and 5 mg of enalapril daily), although the patients on captopril who developed cough were receiving higher doses than those who presented other side effects. A high proportion of patients (29%) continued with the drug for more than six months after cough had developed, suggesting the need for a wider knowledge of this side effect.

Aged↗

PubMed1991

P300 brain activity in seizure patients preceding temporal lobectomy.

Event-related potentials were recorded over occipital and parietal scalp from 20 patients suffering from intractable partial complex seizures prior to undergoing a temporal lobectomy. Subjects were presented with language and nonlanguage visual stimuli using a divided-field, "odd-ball" paradigm. Although behavioral performance (button-press accuracy, reaction time, and running counts) was comparable across all groups (although accuracy was worse for those in the left temporal group), patients showed tremendous variability in both the amplitude and latency of the P300 response. Particularly notable was the observation that more slow wave activity was present among the patients than among the control subjects, and those scheduled for a left temporal resection evinced more amplitude reduction than those scheduled for a right temporal resection. In addition, a number of patients appeared not to show a P300 response at all. These results are discussed in the context of the utility of using noninvasive event-related potential measures to examine both memory impairment and the integrity of the neural structures that mediate memory functioning in certain patient populations.

Adult↗

PubMed1991

Status epilepticus: clinical experience with two special devices for continuous cerebral monitoring.

Continuous cerebral monitoring (CCM) was performed on 34 patients in status epilepticus (SE), using changes in amplitude detected by the cerebral function monitor (CFM) and changes in frequency detected by compressed spectral array (CSA). The EEG was used intermittently to help identify seizure patterns obtained with these methods. Seventeen patients in clinically manifest SE also had non-convulsive seizures. In 17 patients, SE was refractory to conventional anticonvulsants, requiring treatment with pentobarbital or paraldehyde. In these patients, CCM provided dynamic electroencephalographic monitoring of burst-suppression and prompt detection of breakthrough seizures. Patients in SE should undergo CCM to differentiate between non-convulsive seizures and post-ictal state both of which may produce prolonged unresponsiveness following clinical seizures. CCM after data reduction with the two special devices used is a viable and practical alternative to continuous conventional EEG monitoring during SE. However, in order to evaluate the sensitivity and specificity of these methods, it will be necessary to design a study in which both the EEG and the devices using data reduction be used continuously and concurrently.

Adolescent↗

PubMed1991

The prognostic value of residual spikes in the postexcision electrocorticogram after temporal lobectomy.

We correlated the postresection electrocorticograms (ECoGs) of 80 patients who underwent temporal lobectomy under general anesthesia for treatment of intractable complex partial seizures with surgical results in three groups: seizure/aura free (32 patients), auras only (16 patients), and one or more postoperative seizures (32 patients) at mean follow-up times of 34, 31, and 38 months, respectively. Spontaneous "residual spikes," ie, present after all resections, were present in 47% of patients who had no postoperative seizures or auras. However, they occurred in 72% of patients with any postoperative seizures (p less than 0.05). The location (convexity, mesial, or edge of resections) or the distribution (unifocal versus multifocal) of the residual spikes was not of prognostic value. Quantitative studies in 5-minute epochs of the postexcision ECoGs did not reveal a significant difference in the morphology of the residual spikes, ie, the amplitude or firing pattern (single versus polyspike), in the three groups. The group with postoperative seizures showed a higher number of spikes per epoch (greater than or equal to 50), but it was not significant. Although the study shows that patients with residual spikes may have good prognosis, they are at significantly higher risk for postoperative seizures as compared with those without residual spikes. The possibility that intensity of firing of residual spikes may be an additional predictor of outcome warrants further study.

Cerebral Cortex↗

PubMed1991

Intraoperative monitoring of the facial nerve during decompressive surgery for hemifacial spasm.

In 11 consecutive patients, intraoperative electromyographic (EMG) recordings were made from the facial muscles during microvascular decompression for hemifacial spasm. In one patient, recordings could not be obtained for technical reasons, and two patients had no abnormality. In the remaining eight patients, the abnormal response resolved before decompression in two, resolved immediately at the time of decompression in five, and failed to resolve in one. All patients were relieved of their hemifacial spasm. In the five patients whose abnormalities resolved at the time of decompression, there was a precise intraoperative correlation between decompression of the nerve and disappearance of the abnormal EMG response. In three cases, this was a useful guide to the need to decompress more than one vessel. These results confirm the findings of Møller and Jannetta, support the use of this technique for intraoperative monitoring of facial nerve decompression procedures, and provide strong circumstantial evidence that vascular cross-compression is an important etiological factor in hemifacial spasm.

Electromyography↗

PubMed1990

The lateralization of language comprehension using event-related potentials.

Event-Related Potentials were recorded over occipital and parietal scalp from left- and right-handed adults presented with a language and a non-language visual stimulus using a divided field, "oddball" paradigm. The major finding of interest was that the P300 component was larger over the left than the right hemisphere of the right-handers when the language stimulus was presented to the left hemisphere; there were no hemispheric differences for the left-handers, regardless of field of presentation. These results are discussed in the context of developing noninvasive measures to lateralize language function.

Arousal↗

PubMed1990

Serial epilepsy caused by levodopa/carbidopa administration in two patients on hemodialysis.

Two patients with similar clinical features are presented: both patients had chronic renal failure, on hemodialysis for many years but recently begun on a high-flux dialyzer; both had been receiving a carbidopa/levodopa preparation; and both had the onset of hallucinosis and recurrent seizures, which were refractory to anticonvulsants. The first patient died without a diagnosis; the second patient had a dramatic recovery following the administration of vitamin B6. Neither patient was considered to have a renal state sufficiently severe enough to explain their presentation.

Aged↗

PubMed1988

Postprandial blood pressure changes during hemodialysis.

The effect of eating on BP during hemodialysis was examined in nine nondiabetic end-stage renal disease (ESRD) patients. A standard meal was given during 62 of 125 dialysis treatments in a prospectively controlled study. Diastolic (P = 0.01) and mean (P = 0.03) BPs fell significantly faster in the 45-minute postprandial period in the fed treatments compared with equivalent times in the fasting treatments. In this period, symptomatic hypotension occurred 13 times in five patients fed during dialysis compared with two episodes in one patient while fasting (P less than 0.05). Consumption of meals during hemodialysis should be avoided in patients at risk for hypotension during treatment.

Adult↗

PubMed1988

The effect of red cell transfusion on hemodialysis-related hypotension.

Blood pressures of 25 stable end-stage renal disease patients with chronic anemia (mean hemoglobin 5.9 g/dL) who had received 2 units of packed red cells during hemodialysis were studied. Three treatments preceding and three following the transfusion dialysis were compared. Twenty-eight hypotensive episodes preceded and 12 followed transfusion (P = .02). Intravenous sodium chloride used for hypotension declined from a mean of 20.4 to 10.2 mEq per dialysis (P = .01). The rate of decline in mean arterial pressure during dialysis was significantly slower following transfusion (P less than .01). Mean postdialysis weight fell from 62.0 kg before transfusion to 61.5 kg following transfusion (P less than .001). Thus, red cell transfusion raises intradialytic pressure and reduces the frequency of intradialytic hypotension.

Adult↗

PubMed1986

Electrophysiological correlates of a paroxysmal movement disorder.

Averaged electroencephalographic activity related to rhythmic jerking movements was recorded in a patient with a complex neurological symptomatology. The diagnosis of a functional disorder was strongly suggested by his clinical course, inconsistent findings from physical examination, and negative workup. His abnormal movements were associated with the same electrophysiological correlates as normal willed motion, suggesting that averaged movement potentials may provide useful information in the study of patients with suspected functional movement disorders.

Adult↗

PubMed1986

Androgen-binding proteins from human hyperplastic prostate as evaluated by electrophoresis.

Until 1972 it was shown that the androgen action in the prostatic tissue was through receptor proteins. In 1975 the synthesis of methyltrienolone (MT) opened a new field in searching receptor proteins. This synthetic androgen discriminates between receptors and other proteins such as TeBG and albumin. The main purpose in this investigation was to obtain the electrophoretic patterns of human prostatic androgen-binding proteins and compare them with those of other tissues from male genital tract (e.g., testes and epididymis), using as a reference the already described pattern in blood serum. The experimentation was carried out with cytosol (105,000 g) and nuclear fractions from the homogenized tissue. Both fractions were incubated with the tritiated steroids and then treated with dextran-coated charcoal. Polyacrylamide gel electrophoresis (PAGE) was then performed at pH 8.3 with acrylamide (T) 7.7%. The prostatic cytosol incubated with 3H-dihydrotestosterone (3H-DHT) revealed radioactive areas with the following average electrophoretic mobilities relative to Bromophenol Blue (Rf): 0.195, 0.285, 0.815, 0.910. When cytosol was incubated with 3H-MT the pattern showed radioactive peaks with Rf 0.280, 0.570, and 0.969. The nuclear fraction bound 3H-DHT in 0.190, 0.455, 0.570, 0.660, and 1.055 and bound 3H-MT in Rf 1.01. We concluded from these results that the electrophoretic patterns in the prostate gland shared some radioactive areas resembling TeBG and albumin, although they present low binding capacity. The other peaks with different electrophoretic mobilities are in the process of further identification.

Androgen-Binding Protein↗

PubMed1986

Clinical neurophysiology of dementia.

The role of EEG in the study of the dementias is to help in the differential diagnosis of the multiple causes of this syndrome. EEG is useful in differentiating early on between treatable and as of now untreatable forms of dementia. Space-occupying lesions that give rise to dementia are reliably detected by EEG. Infectious, toxic, and metabolic processes are associated with early and severe electroencephalographic abnormalities. The "slow virus" infections show characteristic electrical patterns that reliably distinguish them from the cortical or subcortical dementias. Finally, the EEG may contribute to distinguishing between Alzheimer's disease and MID, two commonly occurring forms of dementia. The paucity of substantial early EEG abnormalities in Alzheimer's disease, although helping to differentiate it from other dementias, leaves us without a currently available physiologic test that provides positive evidence for this condition. Recent studies of EPs, however, suggest that some intermediate latency VEP components may be delayed in patients with Alzheimer's disease when compared with normal subjects. This is encouraging, as latencies in VEPs are more reliable and less variable than amplitude that has previously been reported as "abnormal" in some early Alzheimer patients. Long latency ERPs and CNV also show early abnormalities in Alzheimer's disease. Tests of eye movements such as ERPs are psychophysiologic tests requiring some degree of patient cooperation. Performance on tests of ocular smooth pursuit correlate highly with severity of the dementia syndrome in Alzheimer's disease. In contrast, smooth pursuit testing is usually normal in elderly patients with pseudodementia of depression, suggesting this test may be of some value in differentiating these two clinical disorders. Some evidence exists that smooth pursuit eye movements are also normal, at least in the early and middle stages, in Pick's disease, again suggesting that eye movement testing may prove to have some utility in differentiating this form of dementia from Alzheimer's disease. Ocular scanpaths are abnormal in dementia. They typically are poorly organized and at times perseveratory. In addition, the average durations of eye fixations during directed visual search are altered in dementia as compared with normals. The average eye fixation durations are longer with Alzheimer's disease and briefer in patients with frontal lobe tumors as compared with elderly normal controls. These group differences suggest differing scanning strategies for these two forms of dementia.(ABSTRACT TRUNCATED AT 400 WORDS)

Alzheimer Disease↗

PubMed1985

The EEG of the early premature.

EEGs were taken of 33 premature babies of 27-32 weeks of conceptional age who were considered normal for their conceptional age by clinical criteria. The EEGs were divided into epochs of 1 min each and their characteristics of temporal and spatial organization as well as amount and distribution of special patterns were coded and analyzed. The records were mostly discontinuous, with synchronous and symmetric bursts. There was much rhythmic activity in all frequencies and some patterns were consistently asymmetric. At least one pattern, the sawtooth, seems to be characteristic of this early conceptional age. Follow-up EEGs and clinical examinations were done on 17 children at 6-8 months of age post term. Three more died before 6 months and on one a telephone report was obtained from the mother. The characteristics of the neonatal EEGs were compared with those published on smaller groups of early prematures and those on later premature babies.

Brain↗

PubMed1985

The normal EEG of the human newborn.

In the early premature, the EEG is mostly discontinuous. Discontinuity becomes limited to quiet sleep periods by the 36th week of conceptional age (CA). Temporal theta bursts, or the "sawtooth" pattern, come and go between 27 and 32 weeks' CA. Delta brushes attain their maximum about 32 to 34 weeks' CA and disappear about 40 to 44 weeks' CA. Frontal sharp transients have their peak occurrence at 35 or 36 weeks' CA and are still present at 44 to 48 weeks' CA. The background activity is essentially symmetric but transient patterns are less symmetric and frequently asynchronous. Lack of variability in the record is abnormal after 34 weeks' CA. Responses to isolated light flashes are prominent from very early prematurity through full-term. On the other hand, photic driving is frequent in early prematures (29-32 weeks' CA), but it then declines and is difficult to detect in the full-term neonate. Nonspecific responses to stimulation occur from early prematurity. Sleep--waking cycles are clearly discernible about 37 weeks' CA. Active sleep (rapid eye movement) goes from 60% at 34 weeks' CA to the 25% of adulthood at about 8 months of age. The EEG of the full-term newborn has four patterns, corresponding to three states: the low voltage irregular for wakefulness, high voltage slow and tracé alternant for quiet sleep, and the mixed for either wakefulness or active sleep.

Cerebral Cortex↗