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Biomedical subjects

I Chinchón

Publications and source records attributed to I Chinchón.

At least 19 recordsLinked to original sources
PubMed2001

Mitochondrial DNA point mutation in the COI gene in a patient with McArdle's disease.

We studied a 57-year-old female patient with clinical and biochemical evidences of McArdle's disease. Her muscle biopsy also revealed signs of mitochondrial proliferation, scattered RRF, and a deficit in complex I of the respiratory chain. Molecular genetic analysis showed that the patient was heterozygous for the most common mutation at codon 49 in the myophosphorylase gene. Mitochondrial DNA analysis of muscle tissue revealed an additional G-to-A transition at nucleotide position 7444 in the cytochrome c oxidase subunit I (COI) gene.

Codon↗
PubMed2001

Mitochondrial disease and stroke.

BACKGROUND AND PURPOSE: It is well known that some mitochondrial disorders are responsible for ischemic cerebral infarction in young patients. Our purpose was to determine, in this prospective ongoing study, whether ischemic stroke is the only manifestation of a mitochondrial disorder in young patients. METHODS: Patients aged </=50 years, admitted to the Stroke Unit from January 1999 to May 2000 with a diagnosis of ischemic stroke of unknown origin, were included in the study. All of them had full biochemical and hematologic tests, neuroimaging studies, transesophageal echocardiography, and extracranial and transcranial Doppler sonography. Patent foramen ovale was ruled out. Lactic acid concentrations were measured after anaerobic exercise of the forearm, and a morphological, biochemical, and molecular study after biceps muscle biopsy was performed. RESULTS: Of the 18 patients so far included, 3 (17%) presented lactic acid hyperproduction after physical exercise, and 6 (33%) showed deficit of the mitochondrial respiratory chain complexes. The molecular analyses have confirmed mitochondrial mutations at base pairs 3243 (characteristic of mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes [MELAS]), 4216, and 15 928. CONCLUSIONS: These results suggest that ischemic stroke may be the only manifestation or the initial manifestation of a mitochondrial disorder.

Adolescent↗
PubMed2000

[Recurrent familial brachial plexopathy as the only clinical expression of neuropathy with susceptibility to pressure].

We report a family with hereditary neuropathy with liability to pressure palsies (HNPP) and chromosome 17p11.2 deletion. This family exhibits a peculiar phenotype consisting in recurrent brachial plexopathy episodes. This phenotype has to be distinguished from hereditary neuralgic amyotrophy on clinical grounds. Although the incidence of brachial plexopathy on HNPP is relatively high it is unusual as the sole symptom of the disease. It is noteworthy that in the six published families with this peculiar phenotype most of the acute episodes became evident after sleep. A greater liability of the plexus and a greater vulnerability to mechanical factors during sleep hours are the suggested mechanisms to explain this rare clinical onset. Recurrent painless brachial plexopathy when associated to generalized conduction abnormalities should suggest a HNPP.

Adolescent↗
PubMed1999

[The bent spine syndrome: a focal axial myopathy of late onset].

The bent spine is a rare syndrome appearing at an advanced age which shows a posture of anterior flexion of the trunk, which is reducible and is often hereditary. It is caused by a paresia of the extensor musculature of the trunk by a focal axial myopathy of late onset. We herein describe the case of a 72-year-old woman with a progressive bent spine initiated at the age of 55. Family questioning showed vertical transmission of the process. On exploration paresis of the paravertebral musculature and to a lesser extent of both girdles was observed. Serum CK levels were normal. Vertebral CT showed atrophy with fatty substitution of the paravertebral musculature. EMG of the scapular and paravertebral muscles demonstrated a myopathic pattern. Deltoid muscle biopsy found atrophy of type II fibers and isolated broken red fibers. This case corroborates the myopathic nature of this syndrome. A review of the nosology of the syndrome is also presented.

Age Factors↗
PubMed1999

[Mitochondrial encephalomyopathy of late presentation with progressive ophthalmoplegia, tremor and diffuse leukoencephalopathy].

A 60-year-old woman had developed ptosis, progressive external ophthalmoplegia and action tremor over the last ten years. Physical examination also revealed short stature and retinal pigmentation. Anaerobic forearm exercise test showed increase of basal lactate and rise of lactate/piruvate index. Biceps biopsy displayed numerous ragged red fibers. Respiratory chain studies were consistent with complex I deficiency. Point mutations or deletions in mitochondrial DNA were not found. MR identified a diffuse leukoencephalopathy over both cerebral hemispheres, mesencephalon, pons and cerebellum. The late and sporadic onset of a progressive external ophthalmoplegia outlining a Kearns-Sayre syndrome is striking. A leukoencephalopathy associated with mitochondrial encephalomyopathy is an infrequent finding. The action tremor of this patient could be symptomatic of her mitochondrial disfunction.

Biopsy↗
PubMed1998

Myophosphorylase deficiency associated with a defect in complex I of the mitochondrial respiratory chain.

We studied a 21-year-old patient with clinical, biochemical and histochemical evidence of myophosphorylase deficiency and unusual repetitive episodes of pigmenturia. His muscle biopsy also revealed morphological signs of mitochondrial proliferation and a defect of complex I of the respiratory chain. His mother had exercise intolerance without myoglobinuria and no histochemical evidence of myophosphorylase deficiency. In muscle, the mother showed some ragged-red fibers, normal respiratory chain levels and a significant residual phosphorylase activity. Molecular genetic analysis revealed that the proband was homozygous for the mutation commonly found in McArdle's disease. The mother, father, and the five siblings were all heterozygous for the same mutation. Mitochondrial DNA analysis of the proband's muscle failed to demonstrate known mutations associated with his clinical pattern. Moreover, we sequenced his tRNA(Leu(UUR)) gene, a hot spot for mutations, showing no abnormality.

Adult↗
PubMed1996

[Usefulness of cerebral biopsy in focal cerebral lesions in patients with human immunodeficiency virus infection].

Brain mass lesions (BML) occurred in 10% of patients infected by the human immunodeficiency virus (HIV), as expression of severe and sometimes treatable diseases. However, the management of them is not well established. We analyzed, retrospectively, 26 brain biopsies (22 estereotaxic) in patients with HIV infection and BML to know their usefulness and safety. The inclusion criteria were: Failure of the anti-Toxoplasma empirical treatment, atypical scan appearance for toxoplasmosis, or severe neurological picture. Brain biopsy yielded a diagnosis in 19 patients (73.1%): Progressive multifocal leukoencephalopathy (n = 8; 30.8%), primary central nervous system lymphoma (n = 6; 23.1%), mycobacteriosis (n = 2; 7.7%), toxoplasmosis (n = 2; 7.7%), criptococcosis (n = 1), cryptosporidiosis (n = 1) and HIV-encephalitis (n = 1). In one case there was a multiple diagnosis: mycobacteriosis, toxoplasmosis, and lymphoma. Brain biopsy results decided a change in therapy in 65.4%, the resolution or improvement of the neurological process in 30.8%, and the determination of the prognosis in 30.8%. In 8 cases (30.7%) there were biopsy complications, with secondary mortality in one. Brain biopsy of BML in HIV-infected patients is a diagnostic method with a high overall diagnostic rentability and uncommon non reversible complications, offering the possibility to prescribe a specific and potentially curative treatment.

Adult↗
PubMed1995

[Congenital myopathy with cores and nemaline rods in one family].

We present a mother and 2 children with congenital myopathy whose clinical signs were facial paresis in all three, and mild involvement of the lower extremities in the mother and one son. All three presented skeletal abnormalities, hypertelorism, arched palate, retraction of the Achilles tendon or short neck. Symptoms were not progressive and muscle biopsies showed central cores and nemaline rods in the mother and only nemaline rods in the 2 sons. The mother also suffered carpal tunnel syndrome, as had other members of the family as the result of autosomal dominant inheritance.

Adolescent↗
PubMed1995

[Recessive distal myopathies. Five cases].

We present five patients with distal weakness in the lower extremities with onset in adolescence. Paresis tended to occur in the gastrocnemia in 3 patients and was accompanied by marked elevation of CPK (> 10 times higher than normal). Muscle biopsies showed signs of dystrophy. The clinical picture for these patients was consistent with the diagnosis of recessive distal myopathy (Miyoshi's form). The differential sign in the other 2 cases was greater involvement of the anteroexternal leg muscles and the presence of rimmed vacuoles similar to those characteristic of Nonaka's vacuolar distal myopathy.

Adolescent↗
PubMed1995

[Adult onset mitochondrial myopathy without ophthalmoplegia. Four cases attributable to complex III and IV deficits in the respiratory chain].

Four adults with proximal myopathy of mitochondrial origin but no ocular involvement are presented. Biochemical analysis showed combined complex III and IV deficits in the respiratory chain in all cases, suggesting an apparent correlation between clinical phenotype and biochemical findings. Mitochondrial DNA analysis of muscle from 1 patient failed to detect either large-scale deletion or point mutations at position 3243 of tRNA(Leu(UUR)) or at 8344 of tRNA(Lys). The tissue specificity of the disease and the absence of family history suggest that a mutation in a nuclear DNA gene encoding a specific subunit of muscle could underlie this disease.

Adult↗
PubMed1991

[Pulmonary tumorlets in POEMS syndrome].

POEMS syndrome is a systemic disease characterized by severe chronic polyneuropathy, organomegaly (adenopathy, and liver enlargement) endocrinopathy, monoclonal peak, sclerotic bone lesions and skin changes. We report on a case of complete POEMS syndrome with peripheral arterial thrombosis and multiple lung tumorlets. No antibodies were found against human nervous tissues or Rhesus monkey on patient serum. This case is the first association described of POEMS syndrome and lung tumorlets.

Aged↗
PubMed1991

[Multifocal demyelinating neuropathy with persistent conduction blocks and continuous muscular activity].

A patient developed an initially asymmetric sensory-motor neuropathy, with definite predominance in upper limbs. The examination also disclosed a markedly impaired muscle relaxation. The neurophysiological study showed conduction blocks with continuous muscle activity consisting of myokymias fasciculations and muscle cramps which disappeared after the anesthetic block of the distal nerve segments. In the sural nerve biopsy significant abnormalities were not found. After prednisone and carbamazepine therapy in usual doses the symptoms reverted and the conduction blocks persisted. Neuropathy with persistent conduction blocks is an uncommon disease which exceptionally results in a clinically apparent syndrome of continuous muscle activity. Its recognition is important, as symptoms can disappear after correct therapy.

Adult↗
PubMed1991

[Complex I (NADH coenzyme-Q-reductase) deficiency, MELAS syndrome and hypertrophic cardiomyopathy].

A 24-year-old male had a deficiency of the complex I (NADH coenzyme-Q-reductase) of the mitochondrial respiratory chain, which clinically presented as a mitochondrial encephalomyopathy, with lactic acidosis and stroke-like episodes (MELAS syndrome). The encephalopathic episodes were preceded by migraine and were characterized by focal deficit signs, motor partial seizures and hypodense areas in the CT scan. An echocardiographic diagnosis of hypertrophic cardiomyopathy without intracavitary thrombi was made. It is suggested that hypertrophic cardiomyopathy is caused by the mitochondrial abnormalities that have been reported in the myocardium, and that migraine and cerebral infarctions are associated with abnormalities in the mitochondria from the endothelium and smooth muscle fibres of the cerebral small arteries and arterioles.

Acidosis, Lactic↗
PubMed1990

[Primary pyomyositis in mild climates. Presentation of 2 new cases].

Pyomyositis is an acute bacterial infection which affects striated muscles. It is a relatively rare process in mild climates. Staphylococcus aureus is responsible for 90-95% of cases. Klebsiella pneumoniae pyomyositis is extremely rare with only one other case reported in a mild climate. Two new cases of pyomyositis are described one caused by K. pneumoniae, increasing thus the etiology spectrum in our country, and the other caused by S. aureus ending in fatality, with two focus of pyomyositis (one of which was chronic) and multisystemic secondary affectation. We highlight the appearance of this process in our environment and the necessity to keep it in mind when making a differential diagnosis in order to recognize it and treat it as soon as possible since its prognosis depends on the moment the diagnosis is made.

Adult↗