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J J Poza

Publications and source records attributed to J J Poza.

At least 19 recordsLinked to original sources
PubMed1999

Autosomal dominant lateral temporal epilepsy: clinical and genetic study of a large Basque pedigree linked to chromosome 10q.

We report a large family with a temporal partial epilepsy syndrome inherited in an autosomal dominant mode, with a penetrance of about 80%. This epilepsy syndrome is benign, with age of onset in the second or third decade of life. It is characterized by rare partial seizures, usually secondarily generalized, arising mostly during sleep, without postictal confusion. There is a good response to the antiepileptic therapy but often a recurrence of seizures after drug withdrawal. The partial component, visual (lights, colors, and simple figures) or auditory (buzzing or "humming like a machine"), the existence of temporo-occipital interictal electroencephalographic epileptiform abnormalities, and the hypoperfusion in the temporal lobe detected by interictal hexamethylpropyleneamine oxime-technetium 99m (HMPAO-Tc99m) single-photon emission computed tomography, strongly suggest a lateral temporal lobe origin. The genetic analysis found linkage to chromosome 10q, and localized a gene in a 15-cM interval that overlaps a previously found localization for partial epilepsy in a large three-generation family. This syndrome could be called autosomal dominant lateral temporal epilepsy.

Chromosomes, Human, Pair 10↗
PubMed1998

[Muscular dystrophy due to a mutation in the gene of alpha-sarcoglycan subunit of dystrophin associated protein complex].

Linkage studies have confirmed the existence of clinical an genetic heterogeneity among the muscular dystrophies due to adhalin deficiency. We present the clinical, histological and genetic characteristics in a case of primary adhalinopathy (deficiency of the 50 kD subunit or alpha-sarcoglycan). It was a 19 years-old woman, born of non consanguineous parents, who shows a long evolution myopathy with onset before age 7, a severe evolution and becoming wheelchair bound at 10 years. She showed evident calf pseudohypertrophy and serum creatinkinase (CK) levels were elevated (40-180 times the standard level). The histological pattern showed a destructed fascicular architecture in agreement with severe muscular dystrophy, normal staining with anti-dystrophin monoclonal antibodies and abnormal staining pattern with anti-adhalin antibodies. The molecular study evidenced an homozygous point mutation (Arg-->Cys) at position 77 of exon 3 of the gene coding for the 50 kD subunit of the alpha-sarcoglycan complex localised in chromosome 17. In the light of this case, we suggest a revision of the diagnostic orientation in the muscular dystrophies and we review the new taxonomy of the limb-girdle muscular dystrophies, remarking the clinical signs which could indicate a given genetic locus.

Adult↗
PubMed1998

Cinnarizine-induced parkinsonism: ten years later.

A retrospective study was carried out to investigate the evolution of patients diagnosed with cinnarizine-induced parkinsonism (CIP) over the past 15 years. A total of 74 cases of CIP were found among 172 patients with drug-induced parkinsonism (DIP). Both CIP and other DIP were significantly more frequent in women. No clinical differences between CIP and other DIP were found. Most of the patients (66 of 74) completely recovered after cinnarizine withdrawal in 1-16 months. Eleven patients later developed Parkinson's disease; four of them had previously recovered. Five patients had tardive dyskinesia. CIP accounts for a high proportion of DIP referred to neurologists in populations in which cinnarizine is widely prescribed. The symptoms typically resolve after drug withdrawal, although complete recovery may take more than 1 year.

Aged↗
PubMed1998

Limb-girdle muscular dystrophy in Guipúzcoa (Basque Country, Spain).

The concept of limb-girdle muscular dystrophy (LGMD) is changing rapidly due to the advances in molecular genetics. Recently, seven different gene loci have been described, demonstrating that limb-girdle muscular dystrophy is a heterogeneous syndrome, which includes different diseases with a similar phenotype. In isolated populations which have little genetic exchange with neighbouring populations, an accumulation of cases may be found. We carried out an epidemiological study in Guipúzcoa, a small mountainous Basque province in northern Spain, and found the highest prevalence rate of LGMD described so far: 69 per million. Genetic studies demonstrated that 38 cases corresponded to the LGMD2A type, due to calpain-3 gene mutations. Only one patient with alpha-sarcoglycanopathy was found, and in 12 patients the genetic defect was not identified. Moreover, the particular calpain-3 mutation predominant in Basque chromosomes (exon 22, 2362AG-->TCATCT), has only been rarely found in the rest of the world. This observation strongly suggests a founder effect in the indigenous population of Guipúzcoa. The clinical characteristics of the patients with calpain-3 gene mutations were quite homogeneous and different from the other groups (sarcoglycanopathy and unknown gene defect), allowing for a precise clinical diagnostic. The disease onset was between the ages of 8 and 15 years, in most cases in the pelvic girdle, and the patients became wheelchair-bound between 11 and 28 years after onset. No pseudohypertrophy of calves or contractures were observed. No clear correlations were found between the nature and site of the mutation and the resulting phenotype.

Adult↗
PubMed1997

Adaptation of the lumbar spine to different positions in bicycle racing.

STUDY DESIGN: A radiologic and electromyographic study was done of the adaptation of the lumbar spine to high-performance cycling. OBJECTIVES: To evaluate changes in the lumbar spine produced by different cycling positions on different types of bicycles used during competition. METHODS: Three professional cyclists were observed to evaluate changes in the lumbar spine. Radiographs were obtained of the different positions adopted by the cyclists during competition, and changes in the angles of the lumbar spine were measured. An electromyographic study was done of the abdominal, lumbar, and thoracic paravertebral muscles. RESULTS: The cyclists' positions involved a change from discal lordosis to kyphosis. To obtain a more aerodynamic position, the cyclists flexed the hip and made the pelvis horizontal without changing disc angles. The contraction of paravertebral lumbar muscles was proportional to pedalling intensity and decreased in more aerodynamic positions. The tone of the paravertebral thoracic muscles depended on the extent of cervical hyperextension. Abdominal muscles remained relaxed in all bicycle positions and with all pedalling intensities. CONCLUSIONS: The changes observed could modify the normal biomechanics of the lumbar spine, but the overall mechanical load on the spine is reduced by shifting weight onto the upper limbs. The imbalance that occurs between the activity of flexor and extensor muscles could cause lumbar pain in persons without proper physical preparation.

Adaptation, Physiological↗
PubMed1997

[Neuropathy associated with arteriosclerosis].

OBJECTIVE: To determine the frequency and characteristics of the neuropathy associated with arteriosclerosis. MATERIAL AND METHODS: A prospective clinical and electrophysiological study was made of 29 male patients with arteriosclerosis, in whom other causes of polyneuropathy had been excluded. RESULTS: Eleven patients complained of paresthesiae (mostly mild). In 11 patients there were signs of polyneuropathy on clinical examination. Neurophysiological studies were abnormal in 11 patients, suggesting the presence of predominantly sensitive axonal neuropathy. In five patients with paresthesiae both physical examination and electrophysiological studies were normal. In 17 patients there were changes in the somatosensory evoked potentials. The brainstem auditory evoked potentials of 27 patients were suggestive of diffuse changes in central nervous conduction, together with super-imposed focal lesions. There were no differences as regards age, signs of disease in the legs or of the involvement of widespread illness, whether they were smokers, ex-smokers or non-smokers, the number of cigarettes smoked daily or the total duration of the smoking habit between the patients with and without clinical or electrophysiological polyneuropathy. CONCLUSIONS: Approximately one third of the patients with arteriosclerosis have clinical or electrophysiological signs suggestive of predominantly sensitive axonal polyneuropathy. In some cases the patients had paresthesia but no changes were seen on physical or electrophysiological examination. The evoked potentials showed diffuse changes in central nervous conduction, and in some cases this was associated with signs of focal lesions.

Adult↗
PubMed1997

[Peripheral neuropathy associated with chronic obstructive pulmonary disease].

To determine the frequency and characteristics of neuropathy associated with chronic obstructive pulmonary disease (COPD). This prospective clinical and electrophysiological study enrolled 30 COPD patients (28 men and 2 women) in whom other causes of polyneuropathy had been excluded. Six patients reported slight paresthesias. Clinical examination revealed signs that clearly suggested polyneuropathy in 8 patients (27%) whereas signs were non specific in 14. The neurophysiological study was abnormal in 26 patients (87%), suggesting axonal polyneuropathy that was predominantly sensory. The presence of polyneuropathy was related to age, duration of disease and smoking, but not with sex or pO2 or pCO2 on the date of examination. Approximately one third of patients with COPD show clinical or electrophysiological signs that suggest axonal polyneuropathy that is predominantly sensory, with only slight or no clinical symptoms.

Adult↗
PubMed1996

Frequency of intergenerational contractions of the CTG repeats in myotonic dystrophy.

Myotonic dystrophy (MD), an autosomal dominant multisystemic disorder with a high phenotypic variability, is the most common muscular dystrophy in adult life. The mutation underlying DM has been characterized as an expanded CTG trinucleotide repeat sequence in the 3 untranslated region of a protein kinase gene on chromosome 19q13.2-13.3. We have analyzed the presence of CTG intergenerational variations on transmission in parent-child pairs affected with DM. The series includes 90% of all living affected descendants (symptomatic or asymptomatic) from a given myotonic dystrophy (DM) patient. A contraction of the CTG repeat size was observed in ten parent-child pairs (14.1%) and remained unchanged in five (7%) pairs. The number of CTG repeats decreased in 2/30 maternal transmissions (6.7%) and in 8/41 paternal transmissions (19.5%). We found 14 asymptomatic individuals carrying the CTG expansion among the offspring. In six of them, a contraction of the CTG repeat was observed, and in all six cases, the DM allele was paternally transmitted. Since nearly all the asymptomatic family members of DM patients were analyzed in this series, the observed percentage of contractions can be considered more realistic, even though the number of parent-child pairs is small.

Adult↗
PubMed1996

Frequency of myotonic dystrophy gene carriers in cataract patients.

DNA samples from 231 unselected patients with cataracts were studied to determine the frequency of the DM mutation in cataract patients. A previous epidemiological study established a high prevalence of DM in the population of Guipúzcoa (Basque Country, Spain), 26.5 cases/100,000. We have found two carriers (0.9%) of the DM mutation in patients who are not related to any previously known DM family. The screening of the DM mutation in cataract patients should be restricted to young patients or people with multicoloured and iridescent opacities, in which the risk of carrying the DM premutation could be higher. Our results suggest that subjects with 38 to 80 repeats could constitute the genetic reservoir of the DM mutation.

Adult↗
PubMed1996

[Drug treatment of frequent disorders in patients with Parkinson's disease].

The patient with Parkinson's disease often needs concomitant treatment for disorders that accompany the disease, such as depression, insomnia or constipation, or for frequent concomitant alterations such as dizziness, high blood pressure or heart disease. The many drugs that can worsen motor symptoms in Parkinson's disease must be avoided, especially if use will be prolonged. Not all drugs that induce or aggravate parkinsonism have the same potency. We describe 3 groups: 1) drugs that invariably induce or aggravate parkinsonism if taken long enough or at high enough doses; 2) drugs that only provoke parkinsonism in some individuals, and 3) drugs that interfere with the action of levodopa. Knowledge of these drugs is essential for all doctors who treat patients with Parkinson's disease.

Anticonvulsants↗
PubMed1996

[Drug-induced or aggravated parkinsonism: clinical signs and the changing pattern of implicated drugs].

To determine the prevalence, clinical signs and course of drug-induced Parkinsonism (DIP) in a general neurology practice, as well as to study the changing pattern of drugs implicated. Retrospective study of DIP patients seen between January 1981 and December 1993. Of the 306 cases of parkinsonism seen, 56.8% were induced or aggravated by drugs. This side effects is more frequent in women and often occurs in old age. The drugs implicated most often were cinnarizine, sulpiride and flupentixol. Forty-two patients took 2 drugs simultaneously, whereas 6 took 3. The number of DIP seen increased after 1986 and then remained stable through 1993. Between 1981 and 1988, the drug most often implicated was cinnarizine, though its relative impact decreased in later years. The most frequently seen form of presentation was rigidakinetic syndrome. Neither drug nor age influenced clinical presentation. Parkinsonism disappeared completely within a mean of 5 months in 142 (82%) patients. Twenty-eight (16%) developed Parkinson's disease. Six of them were symptom-free for 12 to 72 months (mean 40 months), whereas 22 never experienced relief from parkinsonism. Sixteen suffered tardive dyskinesia, a complication that was not associated with the use of any particular drug. More than half of the cases of parkinsonism seen in a neurology practice are drug induced or aggravated, generally by psychotropic drugs. The frequency has held steady for the past 6 years. The drugs implicated change as knowledge of their inducement of parkinsonism becomes known. The clinical picture is usually reversible.

Adult↗
PubMed1996

Peripheral neuropathy associated with polycythemia vera.

The aim of this study was to determine the frequency and characteristics of peripheral neuropathy associated to polycythemia vera. A prospective clinical and electrophysiological study was performed of 28 patients with polycythemia vera. Other causes of neuropathy were excluded. Eleven patients experienced paresthesiae, which were usually mild. In 13 (46%) patients, clinical examination revealed features suggesting polyneuropathy. Nerve conduction indexes were abnormal in 20 (71%) patients, suggesting the presence of a predominantly sensory axonal polyneuropathy. In the somatosensory evoked potentials a delay of the P40 wave was seen in 17 patients, while 11 exhibited a delay of the N20 wave. Three of these patients also showed bilateral increases in the I-III, I-V and III-V intervals of brain-stem evoked potentials. In most cases, the delay was moderate and symmetrical. No differences in sex, age, duration of disease, hematocrit values, or platelet counts were found between patients with or without clinical or electrophysiological polyneuropathy. A high percentage of patients with polycythemia vera present clinical or electrophysiological signs of predominantly sensory axonal polyneuropathy which is probably secondary to ischemia, due to increased blood viscosity and platelet dysfunction.

Adult↗
PubMed1995

Contribution of molecular analyses to the estimation of the risk of congenital myotonic dystrophy.

A molecular analysis of the maternal and child CTG repeat size and intergenerational amplification was performed in order to estimate the risk of having a child with congenital myotonic dystrophy (CMD). In a study of 124 affected mother-child pairs (42 mother-CMD and 82 mother-non-CMD) the mean maternal CTG allele in CMD cases was three times higher (700 repeats) than in non-CMD cases (236 repeats). When the maternal allele was in the 50-300 repeats range, 90% of children were non-CMD. In contrast, when the maternal allele was greater than 300 repeats, 59% inherited the congenital form. Furthermore, the risk of having a CMD child is also related to the intergenerational amplification, which was significantly greater in the mother-CMD pairs than in the mother-non-CMD pairs. Although the risk of giving birth to a CMD child always exists for affected mothers, our data show that such a risk is considerably higher if the maternal allele is greater than 300 repeats.

Adult↗