17 Clinical Trials for Various Conditions
Optimal diagnostic management and underlying pathophysiological mechanisms of selective fetal growth restriction (sFGR) in monochorionic diamniotic (MCDA) twin pregnancies have not been fully clarified. The current diagnostic classification system based on three different umbilical artery flow patterns has no increasing scale of severity and the predictive value is limited. Since there is no treatment available for sFGR, predicting fetal deterioration is key in preventing single or double fetal demise. Outcome prediction is furthermore important in the selection of cases that will be offered selective reduction (to provide the larger twin with better prospects), as well as determining monitor frequency and possible hospital admission. As outcome prediction is clinically challenging, patient counselling is too, and parents often encounter a great deal of uncertainty during the pregnancy. Furthermore, little is known about the brain development of sFGR children (both during pregnancy and after birth). Moreover, the psychological impact of an sFGR pregnancy of the future parent)s) has not been studied before. The impact of these factors should be taken into account during patient counseling, which is currently not the case. By our knowledge, this is the first international, multicenter, prospective cohort study on that will address the abovementioned questions and knowledge gaps in MCDA pregnancies complicated by selective fetal growth restriction.
The purpose of this study is to gain better understanding of how the immune system works in twins with and without allergic disease. Healthy volunteers are not specifically targeted. Healthy non-allergic study participants may be found through the course of evaluation for the presence of allergies.
This is a multicenter randomized study designed to determine if physical exam indicated cerclage reduces the incidence of spontaneous preterm birth \<34 weeks in asymptomatic women with twin gestations and dilated cervix, diagnosed by pelvic exam between 16 to 23 6/7 weeks of gestation.
The purpose of this study is to evaluate the use of diode laser photocoagulation of the communicating vessels in twin-to- twin transfusion syndrome (TTTS) with respect to maternal, fetal and neonatal outcomes.
The purpose of this study is to examine the role of genetic and environmental factors in the cause of Parkinson's disease.
This study will examine families in which one sibling of a sibling pair, or twin pair, has developed a systemic rheumatic disease and one has not, to see if and how the two differ in the following: * Blood cell metabolism; * Types of cells in the blood; * Environmental exposures or genetic factors that might explain why one developed disease and the other did not. Families in which one sibling has developed a systemic rheumatic disease, rheumatoid arthritis, systemic lupus erythematosus, scleroderma, dermatomyositis, or myositis, and the other has not, are eligible for this study. The siblings may or may not be twins, but must be of the same gender and be within a 5-year age difference. Biological parents, or, in some cases, children, will also be included in the study. Normal, healthy volunteers will serve as control subjects. Participants will undergo some or all of the following tests and procedures: * Medical history and physical examination. Participants will also be asked permission to obtain medical records for review. * Questionnaires about environmental exposures at work, at home, and elsewhere. Probands (participants with rheumatic disease) and their healthy siblings will also answer questions about infections, vaccinations, medications or dietary supplements, sun exposure, and stressful events during the year before disease diagnosis in the affected sibling. * Blood and urine collection for the following tests: * Routine blood chemistries and other studies to rule out certain diseases or medical problems; * Evidence of past toxic exposures and certain infections; * Presence of cells from the mother in the child s blood and vice versa. (Recent studies suggest that during pregnancy or delivery, cells from the mother and baby may be exchanged and circulate in the body for many years, possibly causing problems); * In twin or sibling pairs, presence of certain genes that may be more common in patients with systematic rheumatic diseases as compared with their unaffected siblings and normal volunteers; * In identical twins, comparison of their blood cell metabolism to see if and how the metabolism differs in people with rheumatic disease. Participants may be asked for permission to have some of their blood and urine samples stored and to obtain previously collected blood or tissue biopsy specimens that are no longer needed for clinical care, for research purposes. They may also be asked to give additional blood or urine samples. Participants will be followed every year for 5 years (either in person or by questionnaire) to evaluate any changes in their condition. The final 5-year evaluation will repeat some of the questionnaires and procedures described above.
This study will test whether 42 days of cannabis abstinence, compared to continued cannabis use, is associated with improvements in cognition and psychiatric disorder symptoms. Identical twins, who are concordant on cannabis use, will be experimentally-manipulated to be discordant for 42 days. Each twin, within a twin pair, will be randomly assigned to either the contingency management condition, incentive-based protocol to promote cannabis abstinence, or control condition, no changes in cannabis use requested.
Respiratory viruses are known to be risk factors for asthma (e.g respiratory syncytial viruses, RSVs, and Human Rhinoviruses, HRVs, may induce bronchiolitis, and wheezing illnesses respectively). The common flu is also known to be a risk factor and the Centers for Disease Control and Prevention (CDC) recommends that asthmatics receive the annual flu vaccine, as a high-risk group for related asthma exacerbations. The investigators will be evaluating the variation in individual responses over time after controlled immune activation following influenza vaccination of monozygotic twins, both discordant for asthma, and concordant non-asthmatic. The transition from initial healthy to immune-system activated physiological states post vaccination will provide unprecedented molecular (omics) data on the molecular dynamics of immune response to vaccination, and novel insight into the flu response. The investigators will infer novel networks and pathways and as well as the dynamics of genes and mechanisms involved in asthma, flu vaccination, and individual responses, and correlate them to evaluated personalized genetic risks in the same study. The investigators will be able to also contrast the vaccination response in asthmatic and non-asthmatic individuals, in a longitudinal approach which has never been performed before using multiple-omics that included an immunization response.
Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the United States. The cause of NAFLD is poorly defined but is thought to involve complex interactions of genetic and environmental factors. NAFLD is often associated with the traits of the metabolic syndrome including diabetes, high cholesterol or elevated blood pressure. Currently, there are no accurate noninvasive means of evaluating NAFLD and its more serious form which includes inflammation that may lead to severe scarring in the liver. The goal of this study is to evaluate shared genetic factors that underlie NAFLD and features of the metabolic syndrome as determined by blood work and radiographic studies in a cohort of twins and first degree relatives.
The purpose of this project is to measure brain markers and cognitive factors in twins with a history of military service with and without PTSD, and to follow them over time and measure changes in brain function and cognitive variables.
The definition of the most 'at-risk' population within highly susceptible groups would provide an opportunity for preemptive therapeutics. A convenient, safe, and tolerable therapy that delays the onset of clinical disease during the pre-symptomatic stage of demyelinating disease would provide a therapeutic alternative to a 'wait and see' approach in subjects at 'high risk' for CIS (clinically isolated syndrome - monosymptomatic demyelinating disease) or MS. Identical twins share the same genes and have the highest rate of shared MS. An identical female with a sister twin with MS has a 34% chance of having MS. Non concordant (no MS yet) identical (monozygotic - from the same sperm-egg zygote) female twins provide an ideal population to find out what factors predict the onset of MS in the non-affected twin. We will recruit 30 identical female twins, one with MS and the other without MS, and obtain brain MRI and biological samples on the non-affected twin and determine if: * the presence of characteristic MS-like lesion(s) on baseline MRI predisposes to MS. * specific proteins in blood or cerebrospinal fluid predispose to the clinical expression of demyelinating disease If we can predict by simple tests (MR brain scan and blood tests) the likelihood of the onset of MS in 'at risk' subjects, and have safe and tolerable therapies, we may be able to prevent the clinical onset of demyelinating disease (MS).
Magnetic Resonance Imaging (MRI) unlike X-rays and CT-scans does not use radiation to create a picture. MRI use as the name implies, magnetism to create pictures with excellent anatomical resolution. Functional MRIs are diagnostic tests that allow doctors to not only view anatomy, but physiology and function. It is for these reasons that MRIs are excellent methods for studying the brain. In this study, researchers will use MRI to assess brain anatomy and function in X and Y chromosome variation, healthy volunteers, and patients with a variety of childhood onset psychiatric disorders. The disorders include attention deficit disorder, autism, congenital adrenal hyperplasia, childhood-onset schizophrenia, dyslexia, obsessive compulsive disorder, Sydenham's chorea, and Tourette's syndrome. Results of the MRIs showing the anatomy of the brain and brain function will be compared across age, sex (gender), and diagnostic groups. Correlations between brain and behavioral measures will be examined for normal and clinical populations....
In this research study, the investigators want to learn more about the role of new innovative surgical devices, the Karl Storz Curved and Straight Fetoscopes for in-utero surgery. A fetoscope is like a small telescope that can see inside of the uterus (womb) during minimally invasive surgery. The curved scope is used for patients with an anterior placenta (front of uterus), while the straight scope is used for patients with a posterior placenta (back of uterus). The scopes will be used to assist in procedures involving fetoscopic laser photocoagulation (FLP), which is a minimally invasive surgery that uses a small camera (fetoscope) to locate abnormal blood vessel connections in the placenta and seal them off using laser energy. These fetoscopes will be utilized in the diagnosis and management of various fetal conditions that can arise during pregnancy. Outcome data will be reported in a descriptive statistical analysis. The investigators will assess the surgical outcomes, short and long-term morbidity, complications, and gestational age of participants in order to evaluate the benefit of using these devices.
The objective of this trial is to compare both strategies (Expectative Vs Fetoscopic laser surgery) for patients with stage 1 TTTS and favorable obstetrical parameters in an international randomized controlled trial. This trial will answer an important question and will help in the management and tailoring of surgical indications in stage 1 TTTS.
Specific Aims: To compare metformin pharmacokinetics in monozygotic and dizygotic twin pairs. Comparing renal clearance of metformin in monozygotic and dizygotic twins will allow us to better understand the influence of heredity on variation in renal elimination. Furthermore, genotyping renal transporter genes in monozygotic and dizygotic twin pairs with significant differences in renal clearance of metformin may give us insight into the genes responsible for this variability.
The purpose of this study is to use brain imaging technology to study the connections between brain regions in children with attention deficit hyperactivity disorder (AD/HD), and comparing them to children without AD/HD. This study will build upon previous brain imaging studies of healthy volunteers and children who have AD/HD. This study will use diffusion tensor magnetic resonance imaging (DT-MRI) to visualize and measure certain parts of the brains of identical twin pairs in which one twin has AD/HD, combined type. Participants in this study will be screened with questionnaires and interviews, psychometric testing, and a physical examination. Participants' medical and educational records may be reviewed. Participants will undergo an MRI scan of the brain. Prior to the MRI, participants will have a training session in a simulated MRI scanner to learn how to lie still during MRI scanning. Participants may be asked to return for a follow-up scan in about 2 years.
Each year world-wide, 2.5 million fetuses die unexpectedly in the last half of pregnancy, 25,000 in the United States, making fetal demise ten-times more common than Sudden Infant Death Syndrome. This study will apply a novel type of non-invasive monitoring, called fetal magnetocardiography (fMCG) used thus far to successfully evaluate fetal arrhythmias, in order to discover potential hidden electrophysiologic abnormalities that could lead to fetal demise in five high-risk pregnancy conditions associated with fetal demise.