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B Vazquez

Publications and source records attributed to B Vazquez.

35 records · Page 2Linked to original sources
PubMed1996

Simple and sensitive high-performance liquid chromatography--fluorescence method for the determination of citrinin application to the analysis of fungal cultures and cheese extracts.

A new and highly sensitive method for the detection of the important mycotoxin, citrinin, has been developed. Spectroscopic studies demonstrate that the fluorescence of this metabolite is influenced by the pH of the environment. This fact was exploited in the chromatographic determination of citrinin with fluorescence detection. The proposed method, based on the addition of 1 M hydrochloric acid as an acidic post-column reagent, has a limit of detection of 0.9 center dot 10(-7) M. Analytical validation shows that linearity can be assumed from 2 center dot 10(-7) to 10(-4) M citrinin. The repeatability and reproducibility are satisfactory, with R.S.D. = 5.1% (n = 9, c = 10(-5) M) and R.S.D. = 7.2% (n = 9, c = 10(-5) M). The method was also applied to the determination of this mycotoxin produced by mould cultures isolated from soft cheese and also from soft cheese and also from cheese extracts spiked with citrinin. The specificity of the method is demonstrated and the necessity for post-column acidification is illustrated on real samples.

Cheese↗
PubMed1996

Clinical features of neocortical temporal lobe epilepsy.

Few studies have examined the clinical features of neocortical temporal lobe epilepsy (NTLE) in carefully selected patients. We reviewed records from 21 patients with NTLE, defined by intracranial electroencephalogram (EEG), who have been seizure free for 1 year or more following temporal lobectomy. The mean age of onset at the time of first seizure was 14 years (range, 1-41 years). Febrile seizures were reported in only 2 patients (9.5%). In contrast to prior mesial temporal lobe epilepsy (MTLE) studies, seizure-free intervals between the initial cerebral insult or first seizure and habitual seizures were uncommon. Possible or known risk factors for epilepsy were reported in 13 of 21 patients (62%). Fifteen (71%) patients reported auras, with experiential phenomena being the most common type. Magnetic resonance imaging was normal or nonspecific in 15 patients, revealed mild hippocampal atrophy in 2, tumors in 2, and heterotopic gray matter and hippocampal atrophy in 1, and cortical dysgenesis in 1. Neuropsychological testing showed deficits consistent with the seizure focus in 13 patients (62%), and Wada test showed ipsilateral memory deficits in 10 (48%). The most common behavioral manifestation was a motionless stare at ictal onset (48%). In contrast to prior studies of MTLE, only 1 NTLE patient had frequent independent, contralateral temporal lobe epileptiform spikes on scalp EEG.

Adolescent↗
PubMed1996

Clinical profile of patients with epileptic and nonepileptic seizures.

Epileptic seizures (ES) and nonepileptic seizures (NES) often coexist in patients with treatment-refractory seizures. There are few data on ictal features of these different seizure types in the same patient. We identified 20 patients with ES from a group of 99 NES patients (ES/NES) and compared this group with patients with only ES or NES. All 20 ES/NES patients developed NES after ES. Clinical features of NES clearly differed from ES in 18 of 20 cases. In patients with ES/NES their ES were similar to seizures in patients with only ES, and their NES were similar to spells in patients with only NES. ES/NES patients were similar to ES patients in electrodiagnostic and neuroimaging studies, and similar to NES patients in psychiatric interviews and inventories. The clinical manifestations of ES and NES in the same patient are usually different. Both types of events may be stereotypic and can be distinguished and characterized during video-EEG recording. Determining what events are more prevalent or disturbing is critical. Psychiatric and antiepileptic drug treatment may be provided accordingly.

Amnesia↗
PubMed1995

Psychiatric classification of nonconversion nonepileptic seizures.

OBJECTIVE: To determine the frequency and type of non-conversion nonepileptic seizures (NES). BACKGROUND: Although conversion disorder is the most common psychiatric disorder among patients with NES, many patients with nonepileptic paroxysmal behavioral events have other psychiatric disorders, with natural histories and treatments different from those of conversion disorder. DESIGN: Retrospective review of a series of consecutive admissions for video-electroencephalography monitoring. All patients identified with NES were interviewed by a psychiatrist. Patients with conversion and other psychiatric disorders were divided into separate groups. SETTING: A comprehensive epilepsy center. RESULTS: Twenty-one patients evaluated for possible epileptic seizures had a psychiatric disorder other than conversion that accounted for their events. Among these patients, Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition (DSM-III-R) anxiety disorders (n = 9) were the most common diagnosed category, followed by all forms of psychotic disorders (n = 7) and impulse control problems in the setting of attention deficit disorder residual type (n = 2). In contrast to 71 patients with conversion NES seen over the same period of time, the non-conversion group showed no female predominance and the nonconversion patients were significantly less likely than the conversion patients to have been physically or sexually abused in childhood or adolescence. CONCLUSIONS: These results support the validity of the nosologic distinction of nonconversion from conversion NES and suggest that DSM-III-R anxiety disorders are an important diagnostic confound in clinical epilepsy.

Conversion Disorder↗
PubMed1995

Arachidonic acid metabolism modulates vasopressin-induced renal vasoconstriction.

Previous studies have shown that cytochrome P450-Arachidonic Acid (P450-AA) metabolites modify the vascular tone of several vessels and that vasopressin (AVP) stimulates P450-AA metabolism. Thus, in the present study, we decided to investigate if the vasoconstrictor effect of AVP is related to activation of P450-AA metabolism. We used the isolated perfused kidney of a rat, to test this hypothesis. Bolus injection of AVP (5.5, 11, 22 and 45 ng) increased the perfusion pressure of the isolated kidney of a rat by 66 +/- 2, 87 +/- 4, 110 +/- 2 and 130 +/- 3 mmHg respectively. This AVP-induced vasoconstriction was significantly reduced by inhibition of AA metabolism with ETYA, or 7 ethoxyresorsorufin (7ER). Furthermore, in vivo induction of P450 system with dexamethasone, enhanced the AVP-induced vasoconstrictor effect. Conversely, depletion of P450 system with SnCl2 diminished the vasoconstrictor response to AVP. Measurement of P450-14cAA metabolites in the renal effluent, showed the presence of 3 radioactive peaks. The % of the recovered radioactivity was 0.12 +/- 0.05%, 0.11 +/- 0.03% and 1.13 +/- 0.5% and corresponded to Dihydroxyeicosatrienoic acids (DHTs), Hydroxyeicosatetraenoic acids (HETEs) and Epoxyeicosatrienoic acids (EETs) respectively, when kidneys were stimulated by AVP (300 ng) the % recovered were 0.34 +/- 0.01%, 0.38 +/- 0.01% and 3.11 +/- 0.7% for the DHTs, HETEs and EETs respectively. Treatment with dexamethasone or SnCl2 potentiated or inhibited the AVP-dependent release of the P450-AA metabolites. In conclusion, we suggest that AVP stimulates AA metabolism via P450 pathway in the kidney and that these AA metabolites participate in the vasoconstrictor effect of AVP in the renal circulation.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1995

Psychogenic basilar migraine: report of four cases.

We discuss four patients with the clinical diagnosis of basilar migraine and suspected coexisting epilepsy who were referred to our epilepsy center. Their symptoms suggested episodic dysfunction in the distribution of the basilar artery, followed by pulsating headache with nausea. Verbal unresponsiveness and sensory symptoms occurred in all four patients; two also had focal paresis or jerking movements. Diagnostic studies excluded other disorders with similar symptoms. None of the patients improved with antimigraine or antiepileptic drugs. Provocation tests with suggestion elicited typical events in three patients and aura and headache in one patient. There were no EEG or ECG abnormalities during spontaneous or provoked episodes. Two patients improved with psychiatric treatment. Conversion disorder or malingering should be considered in patients whose symptoms of basilar migraine are atypical or refractory to treatment.

Adult↗
PubMed1994

Multiple subpial transections in the language cortex.

Multiple subpial transections (MST) were made in language cortex in three patients with medically refractory partial epilepsy. All patients were mapped with extra-operative stimulation using subdural grids over the dominant temporal, frontal and parietal convexity. Two patients had anterior temporal lobectomy and MST in posterior language cortex. One patient who had undergone a previous frontal tumour resection had only MST over the frontoparietal convexity, including frontal and parietal language areas. Both patients with MST in the posterior language cortex had postoperative language dysfunction, which had improved significantly by 9 months after surgery. The patient with MST in frontoparietal language areas had improved language functions immediately postoperatively. The two men with anterior temporal lobectomies and MST are seizure-free at 1 year follow-up and the woman with frontoparietal MST has had a > 70% reduction in seizure frequency at 1 year follow-up.

Adult↗
PubMed1994

New antiepileptic drugs for children: felbamate, gabapentin, lamotrigine, and vigabatrin.

After a 15-year hiatus, several new antiepileptic drugs have been approved or are under Food and Drug Administration investigation for use in the United States. This article reviews four of these new drugs--felbamate, gabapentin, lamotrigine, and vigabatrin. Although these drugs have been primarily developed for use in adults with partial seizures, they will also likely be used in children with partial epilepsy. Pediatric experience with several of these drugs has demonstrated safety and efficacy in other seizure types and epilepsy syndromes. These drugs will be an important addition to the therapeutic armamentarium for pediatric epilepsy. Additional studies are needed to fully explore the safety and efficacy of these drugs in a variety of pediatric epilepsies and to compare them to existing antiepileptic drugs.

Acetates↗
PubMed1994

The prolonged QT syndrome presenting as epilepsy: a report of two cases and literature review.

The prolonged QT syndrome is associated with ventricular tachyarrhythmias and sudden death. We report two patients and review eight previously reported cases of this syndrome, presenting as epilepsy. The average age at the time of the first convulsion was 4.7 years. Episodes were often infrequent, and the time to correct diagnosis ranged from 1 to 28 years. Only one-half the patients had histories suggestive of a familial syndrome. Presyncopal complaints and "lifelessness" prior to seizure activity were common findings in retrospect. Beta-blockade was effective in preventing recurrences in all patients who received treatment.

Adult↗
PubMed1993

Nonepileptic seizures and childhood sexual and physical abuse.

Nonepileptic seizures (NES) must be distinguished from epilepsy to avoid the adverse effects of unnecessary antiepileptic drugs and to initiate appropriate psychiatric treatment. A higher frequency of prior sexual abuse has been suspected in NES, although no prospective controlled study has compared patients with NES and epilepsy. A series of patients with conversion disorder presenting as epilepsy and 140 patients with complex partial epilepsy (CPE) without evidence of conversion were selected from a series of consecutive admissions to a comprehensive epilepsy center. The groups did not differ with respect to age, years of education, race, or marital status, but the percentage of women was greater in the conversion NES group (73.2%) than in the CPE control group (50.7%; p < 0.002). The frequency of a history of sexual or physical abuse was greater in the NES group (32.4%) than in the CPE controls (8.6%; p < 0.000). Severity of sexual but not physical abuse was significantly greater in the NES group relative to controls (p < 0.05). There was a trend for a closer relationship of the perpetrator of sexual abuse to the victim among the NES patients compared with CPE controls (p < 0.1). These results support the impression that childhood abuse is more common among patients with conversion NES than with epilepsy, and suggests that in some cases childhood abuse may be a contributory pathogenetic factor.

Adult↗
PubMed1993

Lateralizing significance of head and eye deviation in secondary generalized tonic-clonic seizures.

We studied 92 secondary generalized tonic-clonic seizures (SGTCS) in 29 patients with a clearly lateralized seizure focus using video-EEG telemetry. An examiner, blind to the EEG, reviewed direction and type (forced versus nonforced) of head/eye deviation (HD). Forced HD consisted of sustained, unnatural tonic or clonic movements. Nonforced HD consisted of sustained deviations that were neither tonic nor clonic and were similar to volitional head movements. Eighty-three of the 92 SGTCS (26 of 29 patients) had lateralized and sustained HD. The direction of HD was contralateral in over 90% of seizures when the movement either (1) continued as the seizure generalized, or (2) occurred in the 10 seconds prior to generalization. The direction of HD was ipsilateral in over 90% of seizures if the movement ended before the seizure began to generalize (in all cases, the movement ended more than 10 seconds before generalization). HD occurring within the first 10 seconds after seizure onset was not of lateralizing significance. Forced HD was 89% contralateral, while nonforced HD was not of lateralizing significance. HD in SGTCS provides information on seizure focus lateralization.

Adolescent↗
PubMed1993

Behavioral changes associated with epilepsy.

Epilepsy can be accompanied by changes in cognition, personality, affect, and other elements of behavior. There is no single epileptic constitution or personality complex. A unifying theme to the behavior in epilepsy is diversity. As one looks at the behavioral traits reported in epilepsy, a specific and consistent pattern is lacking. Rather, extremes of behavior are accentuated: sometimes in one direction, often in both directions. Changes in emotional state are prominent among behavioral features in epilepsy. Some authors describe a prominent deepening or increase in emotionality, whereas others identify a global decrease in emotional life and content. Emotional lability is also reported. Sexuality and libido are typically decreased, but fetishism, transvestism, exhibitionism, and hypersexual episodes also occur. Concerns over morality may be lacking or exaggerated. Patients may be irritable and aggressive or timid and apathetic. The impressive list of people with epilepsy in politics, religion, arts, and sciences suggests a positive expression of this behavioral spectrum. Psychosis, depression, paranoia, and personality disorders may represent a negative pole of epilepsy-related behavioral changes. The most important aspect of behavioral changes in epilepsy for physicians is to recognize and treat dysfunctional behavior. Depression is a common problem that is often unrecognized and untreated. Other treatable problems include impotence, anxiety, panic attacks, and psychosis. Identifying risk factors will, it is hoped, assist in developing methods to prevent these disorders.

Anxiety Disorders↗
PubMed1988

The extended latissimus dorsi flap in repair of anterior abdominal wall defects.

Large abdominal wall defects (ventral hernias) can be difficult to repair. Some defects are not amenable to primary repair or the use of synthetic mesh because of repeated recurrence or wound infection. In complicated situations such as that mentioned above, the extended latissimus dorsi muscle flap has been used to repair upper and middle abdominal wall defects. This method has been utilized in six patients, and there has been no recurrence of the defect or evidence of a lumbar hernia. The follow-up has been from 7 to 66 months. The extended latissimus dorsi muscle flap has proven to be an excellent alternative in the repair of complicated abdominal wall defects.

Abdominal Muscles↗
PubMed1987

Breast augmentation: a review of subglandular and submuscular implantation.

A study of 156 patients who underwent augmentation mammoplasty at the Medical College of Georgia from June 1980 to July 1985 is presented. Complete records on 89 patients with 196 implants were obtained. A retrospective analysis with respect to capsular contracture was undertaken. Possible influential variables including age of patient, type of prosthesis, operative blood loss, use of local steroids, and site of insertion (i.e., submuscular versus subglandular) were considered. The site of implant insertion was the only statistically significant factor affecting capsular contracture. The incidence of capsular contracture was 9.4% with the submuscular approach and 58.0% with subglandular contracture. The followup time for the submuscular group was 17.4 months (range of 6-36 months) with the mean time of capsule contracture occurring 4.5 months after insertion. There were no significant differences in intraoperative blood loss or elapsed operating time between the submuscular and the subglandular placements of the prosthesis. This study confirms the submuscular technique of augmentation mammoplasty as the most reliable method of reducing the high incidence of capsular contracture.

Adult↗
PubMed1986

Modified Thiersch procedure with silastic mesh implant: a simple solution for fecal incontinence and severe prolapse.

Most of the surgical procedures proposed for the treatment of fecal incontinence associated with prolapse are associated with considerable morbidity and mortality. We used a modified Thiersch procedure with a Silastic mesh implant (Dow-Corning 501-3) on a series of 12 patients over a period of 2 1/2 years. Nine patients obtained excellent control of the prolapse and incontinence. Only one patient was dissatisfied with her operation. The excellent results reported by other authors using a Silastic mesh implant have been reproduced in this small series of patients. This relatively safe and simple operation may still be the procedure of choice for fecal incontinence and rectal prolapse.

Adult↗