View clinical trials related to Mitochondrial Diseases.
Filter by:Hypothesis: Many patients with underlying mitochondrial disorders have feeding problems because of poor gastrointestinal motility; feeding problems lead to growth impairment and many affected children are malnourished.
Summary. At the present, the investigators do not have the perfect anesthetic for mitochondrial patients. When possible, consideration should be given to the use of local anesthetics in small amounts. When a general anesthetic is necessary, they each carry significant risks and have been associated with poor outcomes. At present it is not possible to eliminate one group as less safe than others. What is clear is that these patients must be monitored more closely than other patients. The advent of the bispectral index (BIS) monitor may allow us to monitor their depth of anesthesia more closely and thus expose these patients only to the minimum amount of drug necessary to carry out the surgical procedure. Purpose. The investigators hypothesize that specific mitochondrial diseases, in particular those that decrease complex I function, make certain children hypersensitive to volatile anesthetics. These same patients may be at increased risk for adverse outcomes following general anesthesia. The specific aims of this application are: 1. Determine which molecular defects in mitochondrial function lead to alter sensitivity to the VA sevoflurane. 2. Establish the relative safety of sevoflurane in treatment of patients with mitochondrial disease. The investigators plan to monitor patients with mitochondrial disease using expanded measures of cardiovascular stability and measurements of brain electrical activity while slowly inducing general anesthesia. The investigators will use those measurements to limit the amount of anesthetic these patients receive in an attempt to minimize their risk. In addition, the investigators will correlate their sensitivity to the type of mitochondrial defect so that the investigators may be able to predict which patients are likely to have an increased sensitivity.
The investigators propose to evaluate the effect of bezafibrate on metabolism during exercise in 22 adult patients affected with carnitine palmitoyltransferase II (CPTII) or very-long chain acyl-CoA-dehydrogenase (VLCAD) deficiencies. This study will be an 9-month, randomized, double-blind, placebo-controlled crossover trial. The trial will be conducted in two centers: Institut de Myologie, Pitié-Salpêtrière Hospital in France, and Rigshospitalet, University of Copenhagen, in Denmark. The main criteria for assessing the potential effect of this drug will be the fat oxidation rate studied during a moderate workload on cycle ergometer, after infusion of stable isotopes (palmitate and glucose tracers).
Mitochondrial diseases are a heterogeneous group caused by genetic defects in mitochondrial DNA or in nuclear genes. POLG is the most frequently involved gene in mtDNA instability diseases resulting in mtDNA multiple deletion and/or depletion. It encodes the DNA polymerase gamma (POLĪ³), the only known DNA polymerase found in mammalian mitochondria. Mutations in POLG could explain 45% of familial progressive external ophtalmoplegia associated with multiple mtDNA deletions. However, in more than 70%, the analysis of the genes involved in mtDNA instability remains unsuccessful. To date, these genes are screened by sequencing methods that are not able to detect large-scale rearrangements. In order to detect possible large-scale rearrangements, the investigators propose to develop a new assay based on QMPSF (Quantitative Multiplex PCR of Short fluorescent Fragments) able to detect exon deletions and duplications. the investigators propose to screen the POLG gene by QMPSF in at least twenty patients with either no mutation or only one mutation detected in POLG and no mutation in other genes such as TWINKLE and ANT1. This study would allow the investigators to know if large-scale rearrangements occur in the POLG gene and to estimate their frequency in patients with mtDNA instability. These data are important to know if the sequencing analysis of POLG should be completed by the screening for partial deletions and duplications to ensure an accurate molecular diagnosis of these syndromes. Moreover, this method could be extended to ANT1 and TWINKLE genes.
Mitochondrial diseases are the most frequent metabolic diseases (2.5 persons among 10 000) and are clinically heterogeneous making diagnosis particularly challenging for clinicians. Molecular analysis of mitochondrial DNA (mtDNA) is a critical step in diagnosis and genetic counselling of respiratory chain defects. DNA sequencing remains the gold standard but it is time-consuming and fails to detect mutations that may be present at a low heteroplasmic level (20% or below); therefore the diagnosis is yet based on the detection of a few number of pathogenic mutations. The present study aims to evaluate the benefit and the cost of a diagnosis strategy based on the combined use of 2 techniques named "Surveyor Nuclease" and "Mitochip". Surveyor nuclease is a mismatch-specific DNA endonuclease that will be used for screening the entire mtDNA in order to identify heteroplasmic mutations. In absence of any identified mutation, another technique based on the use an oligonucleotide sequencing microarray (MitoChip) will be performed for the identification of homoplasmic mutations. Mitochip is an array-based sequencing platform for rapid and high-throughput analysis of mitochondrial DNA. The economical study will compare the cost of these techniques to the standard diagnosis method in term of direct and indirect costs
The objective of this research protocol is to continue investigation of the nature and prevalence of mitochondria disease and to aid patients and health care providers in the understanding of these complex disorders. This research study brings together many clinical sub-specialists to address the etiology of these disorders and to develop more effective approaches for their diagnoses and more reliable prognoses.
RATIONALE: Studying biopsy, bone marrow, and blood samples from patients with cytopenia that did not respond to treatment may help doctors learn more about the disease and plan the best treatment. PURPOSE: This laboratory study is assessing immune function in young patients with cytopenia that did not respond to treatment.
Numerous studies have demonstrated that excess perivisceral adipose tissue is associated with metabolic diseases such as insulin resistance. In skeletal muscle, insulin resistance has been correlated with reduced mitochondrial oxidative functions. According to the actual theory, mitochondrial dysfunctions are proposed to play a causal role in the aetiology of insulin resistance. Mechanisms involve increased intramyocellular lipids storage. Yet, the causes responsible for the decline in muscle mitochondrial functions remain to be elucidated. The investigators hypothesize that these alterations are induced by combined changes in plasma profiles of lipids and adipokines, which originate from perivisceral adipose tissue. The study aims at answering the following questions : - Are muscle mitochondrial functions altered in association with increased perivisceral adipose tissue storage? - Do changes in the pattern of plasma lipids and adipokines explain this correlation?
To show that oral CoQ10 is a safe and effective treatment for children with inborn errors of mitochondrial energy metabolism due to defects in specific respiratory chain (RC) complexes or mitochondrial DNA (mtDNA) mutations, and that this beneficial action is reflected in improved motor and neurobehavioral function.
This study will examine metabolic and biological factors in people with Li-Fraumeni syndrome, a rare hereditary disorder that greatly increases a person's susceptibility to cancer. Patients have a mutation in the p53 tumor suppressor gene, which normally helps control cell growth. This gene may control metabolism as well as cancer susceptibility, and the study findings may help improve our understanding of not only cancer but also other conditions, such as cardiovascular function. Healthy normal volunteers and patients with the Li-Fraumeni syndrome and their family members may be eligible for this study. Candidates must be at least 18 years of age, in overall good health and cancer-free within 1 year of entering the study. Participants undergo the following procedures: - Blood tests for routine lab values and for research purposes. - ECG and echocardiogram (heart ultrasound) to evaluate heart structure and function. - Resting and exercise metabolic stress testing: The subject first relaxes in a chair wearing the facemask and then exercises on a stationary bicycle or treadmill while wearing the mask. This test uses the facemask to measure oxygen usage by the body to determine metabolic fitness. Electrodes are placed on the body to monitor the heart in an identical manner to a standard exercise stress test. - Magnetic resonance imaging of metabolism: The subject lies on a bed that slides into a large magnet (the MRI scanner) for up to 60 minutes. During scanning, the arm or leg muscles are stressed by inflating a blood pressure cuff and by exercising the limb for several minutes. Subjects may be asked to squeeze a rubber ball or exercise with a foot pedal. Immediately afterwards, the pressure in the cuff is released and remains deflated for 10 to 15 minutes. No more than three 5-minute episodes of blood flow stoppage are performed. - Standard MRI scan of exercised limb to determine muscle volume. - Brachial artery reactivity test to measure blood vessel function: Before the exercise stress testing, subjects lie on a stretcher while the brachial artery (artery in the forearm) is imaged using a noninvasive ultrasound method. Artery size and blood flow velocity are measured before and after inflating a blood pressure cuff on the forearm. Vessel size and flow velocity measurements are repeated after 15 minutes and again after administration of nitroglycerin under the tongue. - Oral glucose tolerance testing to test for diabetes: To assess sugar metabolism, subjects drink a sugar solution. Blood samples are collected before drinking the solution and 1 and 2 hours after drinking the solution. - Muscle biopsy (optional according to subject preference): Subjects may be given small amounts of sedation for the procedure. A small area of skin over a leg muscle is numbed and a small amount of muscle tissue is surgically removed.