1/8. vocal cord paralysis and hypoventilation in a patient with suspected leigh disease.The authors report the case of a 16-month-old male with suspected leigh disease, which was diagnosed on the basis of the clinical manifestations, abnormal lactate stimulation test, proton magnetic resonance spectroscopy, and neuroradiologic findings. Progressive stridor resulting from bilateral vocal cord paralysis and hypoventilation was evident. The authors suggest that for infants or children who exhibit vocal cord paralysis, mitochondrial disorders, such as leigh disease, should be considered.- - - - - - - - - - ranking = 1keywords = spectroscopy (Clic here for more details about this article) |
2/8. Single large-scale mitochondrial dna deletion in a patient with encephalopathy, cardiomyopathy, and prominent intestinal pseudo-obstruction.We studied a 62 year-old woman with a clinical phenotype characterized by encephalopathy, restrictive cardiomyopathy, and prominent intestinal pseudo-obstruction. Muscle morphology showed ragged red fibres with ultrastructurally abnormal mitochondrial whereas muscle respiratory chain was normal. Molecular genetics revealed the 'common deletion' in mtDNA, which represented 40% of total mtDNA. These data expand and confirm the wide clinical spectrum of mitochondrial disorders associated with single large-scale mtDNA deletions.- - - - - - - - - - ranking = 0.0077074019346583keywords = spectrum (Clic here for more details about this article) |
3/8. Mitochondrial encephalomyopathy: comparison of conventional MR imaging with diffusion-weighted and diffusion tensor imaging: case report.Summary: Conventional MR imaging, MR spectroscopy, diffusion-weighted imaging, and diffusion tensor imaging were performed in a 5-month-old male patient with mitochondrial encephalomyopathy. On conventional T2-weighted MR images, symmetric, confluent high signal intensity was found in the temporoparietal white matter. A large lactate peak and decreased N-acetylaspartate were found in this region on proton MR spectroscopic images. Diffusion-weighted imaging showed increased apparent diffusion coefficient, representing vasogenic edema. diffusion tensor imaging revealed decreased anisotropy, consistent with injury to the oligodendro-axonal unit. A muscle biopsy specimen revealed an isolated complex III enzyme respiratory chain deficiency. Diffusion-weighted and diffusion tensor imaging are valuable techniques for the characterization of hyperintense lesions on T2-weighted MR images in cases of mitochondrial encephalomyopathy.- - - - - - - - - - ranking = 1keywords = spectroscopy (Clic here for more details about this article) |
4/8. Subacute necrotizing encephalopathy in a pig-tailed macaque (macaca nemestrina) that resembles mitochondrial encephalopathy in humans.A male pig-tailed macaque (macaca nemestrina), approximately 5 years old, was found to be vision-impaired and to have profound behavioral abnormalities, including hyperactivity and self-injurious behavior that was not amenable to amelioration by environmental enrichment. Facial and skeletal dysmorphisms also were noted. magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning revealed areas of possible infarction in the occipital lobes and megaventriculosis. At necropsy, following euthanasia for humane reasons, severe polio- and leukoencephalomalacia accompanied by megaventriculosis were seen in both occipital lobes and in several sulci of the parietal and frontal lobes. light microscopic findings included loss of neocortical structure, with necrosis, neuronal loss, astrogliosis, vascular proliferation, mild spongiosis, and demyelination. The extent and severity of lesions were most pronounced in the occipital lobes and were greater in the left than in the right hemisphere. Other lesions included mild bilateral atrophy of the optic nerves, thymic involution, necrotizing dermatitis due to trauma, and a spectrum of spermatozoal abnormalities. The imaging and gross and light microscopic changes found in this animal resemble the mitochondrial encephalopathies of humans; this was corroborated by results of immunohistochemical analysis demonstrating decreased expression of enzymes of the mitochondrial oxidative complex ([OC]-I, -III, and -IV) in brain and muscle, and detection of fibrinogen immunoreactivity in neurons and glial cells. The spermatozoal defects may represent yet another aspect of a mitochondrial defect.- - - - - - - - - - ranking = 0.0077074019346583keywords = spectrum (Clic here for more details about this article) |
5/8. Chronic progressive external ophthalmoplegia and myalgia associated with tubular aggregates.Tubular aggregates represent a distinct myopathological feature characterized by basophilic sharply demarcated irregularly shaped subsarcolemmal zones consisting of parallel double-walled tubules of unknown subcellular origin. They are found on rare occasions in a wide spectrum of myopathies, but their significance for the development of muscular symptoms has not yet been fully established. We describe a patient with chronic progressive external ophthalmoplegia (CPEO) associated with exercise-induced myalgia and tubular aggregates in skeletal muscle. The association of CPEO with tubular aggregates has not been reported before and represents an important differential diagnosis to other syndromes associated with CPEO, especially mitochondrial encephalomyopathies.- - - - - - - - - - ranking = 0.0077074019346583keywords = spectrum (Clic here for more details about this article) |
6/8. Novel mutation in the mitochondrial dna tRNA glycine gene associated with sudden unexpected death.We describe an A-to-G transition at nucleotide 10044 in the tRNA(Gly) gene of mitochondrial dna in a sibship in which the proband died at age 8 years after a severe encephalopathy, a brother died of sudden and unexpected death, and the other six siblings had a combination of symptoms, including apparent life-threatening events and gastroesophageal reflux. This novel mutation was very abundant (> 90%) in liver and muscle of the proband and in several tissues, including blood, from his affected siblings (range 91-99%) but was less abundant in blood from the asymptomatic mother (88%) and maternal grandmother (85%). Our findings further enlarge the spectrum of clinical presentations associated with mitochondrial dna mutations.- - - - - - - - - - ranking = 0.0077074019346583keywords = spectrum (Clic here for more details about this article) |
7/8. Mitochondrial encephalomyopathy with coenzyme Q10 deficiency.Coenzyme Q10 (CoQ10) transfers electrons from complexes I and II of the mitochondrial respiratory chain to complex III. There is one published report of human CoQ10 deficiency describing two sisters with encephalopathy, proximal weakness, myoglobinuria, and lactic acidosis. We report a patient who had delayed motor milestones, proximal weakness, premature exertional fatigue, and episodes of exercise-induced pigmenturia. She also developed partial-complex seizures. serum creatine kinase was approximately four times the upper limit of normal and venous lactate was mildly elevated. Skeletal muscle biopsy revealed many ragged-red fibers, cytochrome c oxidase-deficient fibers, and excess lipid. In isolated muscle mitochondria, impaired oxygen consumption was corrected by the addition of decylubiquinone. During standardized exercise, ventilatory and circulatory responses were compatible with a defect of oxidation-phosphorylation, which was confirmed by near-infrared spectroscopy analysis. Biochemical analysis of muscle extracts revealed decreased activities of complexes I II and I III, while CoQ10 concentration was less than 25% of normal. With a brief course of CoQ10 (150 mg daily), the patient reported subjective improvement. The triad of CNS involvement, recurrent myoglobinuria, and ragged-red fibers should alert clinicians to the possibility of CoQ10 deficiency.- - - - - - - - - - ranking = 1keywords = spectroscopy (Clic here for more details about this article) |
8/8. MR imaging and proton MR spectroscopy in A-to-G substitution at nucleotide position 3243 of leucine transfer rna.MR imaging of the brain in a 38-year-old woman with maternally inherited diabetes and deafness (MIDD) showed extensive subcortical and basal ganglia high signal intensity on T2-weighted studies though she was neurologically asymptomatic. High-signal-intensity changes were also seen in the basal ganglia on T1-weighted studies. Proton MR spectroscopy showed increased lactate, an increased choline/creatine ratio, and a decreased N-acetylaspartate/creatine ratio. Our observations suggest that patients with MIDD may have subclinical neurologic dysfunction identifiable by proton MR spectroscopy.- - - - - - - - - - ranking = 6keywords = spectroscopy (Clic here for more details about this article) |