Active clinical trials for "Depressive Disorder, Major"

Objective: Metabotropic glutamate receptors (mGluRs) are G-protein coupled receptors that respond to glutamate by activating proteins inside nerve cells that affect cell metabolism, thereby fine-tuning the signals sent between cells to maintain balance in neuronal activity. mGluR subtype 1 (mGluR1s) are located in several brain regions, including the cerebellum, hippocampus, olfactory bulb, and basal ganglia. mGluR1 activation stimulates phospholipase C, resulting in phosphoinositide hydrolysis and increased intracellular calcium levels. Successful development of a positron emission tomography (PET) ligand to image mGlurR1 would impact clinical management of brain disorders characterized by disruptions in glutamatergic transmission, including anxiety and stress disorders, drug addiction, epilepsy, Huntington s disease, and Parkinson s disease. However, detailed study of mGluR1s has heretofore been hindered by the lack of high affinity and selective ligands for this receptor subtype. The present protocol will evaluate the ability of a new PET ligand, [18F]FIMX, to image and quantify mGluR1 in the brain of healthy human volunteers. This protocol covers four phases: Phase 0: screening whole-body scan; Phase 1: kinetic brain imaging to quantify mGluR1 in brain relative to concurrent measurement of the parent radioligand in arterial plasma; Phase 2: if the tracer is successful in Phase 1, we will estimate radiation-absorbed doses of [18F]FIMX by performing whole body imaging; Phase 3: test-retest analysis of brain binding relative to concurrent measurement of the parent radioligand in arterial plasma. Study Population: Healthy adult female and male volunteers (n=22, ages 18 to 55) will undergo brain or whole-body imaging.. Design: This study will begin with a screening whole-body scan to confirm that the radioactivity has fairly broad distribution in several organs. For absolute quantification of mGluR1, 22 healthy controls will have brain PET imaging using [18F]FIMX and an arterial line. Up to 12 of them will have a test-retest scan. Eight additional subjects will have a whole body PET scan for dosimetry, which does not require an arterial line. <TAB> Outcome Measures To assess absolute quantitation of mGluR1 with [18F]FIMX, we will primarily use two outcome measures: the identifiability and time stability of distribution volume calculated with compartmental modeling. In test-retest study, we will calculate the retest variability. To assess whole-body biodistribution and dosimetry of [18F]FIMX we will use the organ time-activity curves....

The investigators propose a multi-source pattern which integrates neuroimaging data associated with multiple, symptom-related neural processes relevant in depression to improve classification accuracy. The investigators conclude that combining brain activation related to the core-symptoms of depression using the multi-source monitoring data substantially increases classification accuracy while providing a sparse relational neuromarkers-model for future prediction.

The MoodNetwork, a patient-powered research network (PPRN), is one of 18 PPRNs participating in Patient-Centered Outcomes Research Institute's (PCORI) PCORnet network. Its objective is to improve the nation's capacity to conduct comparative effectiveness research that reflects questions of greatest importance to patients and other stakeholders. A robust data infrastructure will be built that, in phase one, allows participants to contribute data, including those from participant questionnaires, visualize their own health information in intuitive and helpful ways, and share their aggregated de-identified health information within and outside of the Network.

Depression is a debilitating illness with a risk of developing a treatment resistant form. Currently, diagnosis is purely clinical with little features available to identify potentially adverse developments. Clinical features such as early onset age, prolonged episodes, anxiety, somatic symptoms and apathy are all arguments raising fears the onset of resistance to conventional treatments. According to neuroimaging knowledge about the pathophysiological mechanisms, involving front-limbic functional networks supporting the functions of emotional regulation and reward system, recent work has focused on the identification of neuroimaging biomarkers predicting therapeutic response. Among the regions of interest identified, the anterior cingulate cortex, amygdala, hippocampus, and regions participating in the Default Mode Network Training (Medial prefrontal cortex, posterior cingulate cortex, inferior parietal lobe) are most frequently areas associated with the prediction of therapeutic response. Limitations most reported in these studies are the heterogeneity of experimental paradigms (resting state, cognitive or emotional functional tasks), imaging (PET scan, MRI) the heterogeneity of clinical resistance criteria forms studied, different techniques (as that we consider remission (threshold score) or response (50% decrease from baseline score), and the sample size. Knowing that MRI into daily clinical practice in the SHU of Adult Psychiatry, as the balance sheet of the disease, monitoring its evolution, as in assumption rTMS (repetitive Transcranial Magnetic Stimulation) (pretreatment assessment and neuro), the identification of neuroimaging biomarkers in a population of patients with clinical criteria of Mood Depressive Episode, with an acquisition of identical and reproducible image daily routine methodology appears to be a reliable way to correct the heterogeneity of conventionally published studies on the topic. This study aim to identify, in routine care, predictive clinical and neuroimaging markers of poor outcome in major depressive disorder.

The investigators will (1) detect the associations between brain-derived neurotrophic factor (BDNF) DNA methylation, histone modification, depressive symptoms, suicidal behavior and antidepressant responses in major depressive disorder (MDD) patients, (2) check the correlation between blood BDNF protein and RNA and BDNF rs6265 gene, and (3) discuss the possible mechanisms of epigenetic regulation of BDNF in Taiwanese major depressive patients.

The main objective of this observational study is to characterize new users of quetiapine XR as well as new users of other study drugs (i.e. the comparison group) and to quantify the risk of developing newly diagnosed outcomes of interest in new users of quetiapine XR as well as in other study drugs.

This study will compare levels of p11 protein in people with and without major depressive disorder (MDD) and examine if p11 levels in patients are affected by treatment with citalopram (Celexa). Healthy normal volunteers and patients with chronic or recurrent major depression between 18 and 65 years of age may be eligible for this study. Participants undergo the following tests and procedures: Healthy Volunteers Psychiatric interview and medical examination, questions about family history Blood draw Patients with MDD Phase 1 - Evaluation and Discontinuation of Medications Physical examination, electrocardiogram, blood tests Gradual antidepressant medication withdrawal, followed by 2- to 6-week drug-free period. If needed, medicines for anxiety and difficulty sleeping may be prescribed. Phase 2 Citalopram Treatment Start daily citalopram treatment Evaluations at the start of phase 2 and every week for 8 weeks with following procedures: Symptoms ratings interview and questionnaires Review of side effects and new medications Blood pressure and pulse measurements Blood and urine tests At the end of the study, plans are developed for long-term treatment and transfer of care to the patient s own physician. ...

Objective: To study the relative balance of GABA (A) binding potential and glutamate utilization in subjects with localization-related epilepsy with and without depression, subjects with major depressive disorder alone, and in subjects with generalized epilepsy (expected not to have significant comorbid depression). Pilot data shows that GABA(A) binding potential and glutamate utilization are tightly coupled in healthy subjects particularly in the mesial temporal lobe. We hypothesize that subjects with epilepsy will not exhibit the same degree of coupling, and that subjects with both epilepsy and depression will exhibit an even more pronounced decoupling. Study Population: Subjects aged 18-55 with localization-related epilepsy with and without depression, subjects with generalized epilepsy, subjects with major depressive disorder (MDD) alone, and healthy controls. Design: This is a neuroimaging study, using positron emission tomography (PET) with [11C]flumazenil, to measure GABA(A) binding potential, and [18F]fluorodeoxyglucose, to measure glucose utilization (reflective of neuronal glutamate release) Magnetic resonance spectroscopy (MRS), will be used to measure GABA and glutamate in the mesial temporal cortex, and corroborate the PET results. Structural magnetic resonance images (MRI) will be obtained for MRS localization and partial volume correction of PET images. Outcome measures: The binding potential of GABA(A), the regional rate of glucose metabolism, and the levels of GABA and glutamate as measured by MRS. Patients will be stratified by seizure type and depression ratings. ...

Context - As men age, testosterone levels decline leading to symptoms that overlap with the symptoms of major depression. Little is known about the potential role of testosterone in the treatment of major depression.Objective - To assess the levels of bioavailable testosterone and total levels of testosterone in men diagnosed with major depressive disorder between the ages of 40 and 65.Design, Setting and Participants - 50 men between the ages of 40 and 65 and who suffer from major depressive disorder will be compared with 50 age matched healthy controls in an outpatient hospital setting. Main Outcome Measures - Bioavailable testosterone and total testosterone levels will be measured as well as blood pressure, pulse rate, height, weight, waist and hip measurements. Medical and psychiatric history will be assessed by the study physician. The Mini International Neuropsychiatric Interview (MINI) will be used to administered by the physician to ensure that the patient meets the DSM-IV criteria for Major Depression. The Hamilton Depression Rating Scale (HAM-D-17) will be used to assess depression symptom severity. A Symptom/Side Effect Rating Scale will also be administered to measure the presence and severity of side effects that each patient may be experiencing. In addition, the SEX FX questionnaire will be administered. Each patient will be asked to complete a series of self-report measures including the Social Adaptation Self-Evaluation Scale Questionnaire (SASS), the Androgen Deficiency in Aging Males (ADAM) and the Beck Depression Inventory (BDI-II).

This study will investigate how the brain process emotions in healthy people and in patients who have major depression in order to better understand the causes of depression. It will examine what happens in the brain when a person responds to words related to different emotions while the brain's ability to manufacture a chemical called serotonin is reduced. Serotonin regulates functions such as emotion, anxiety and sleep, and stress hormones such as cortisol. In this study, participants' serotonin levels are reduced by depleting tryptophan, an amino acid that is the main building block for serotonin. Healthy volunteers and patients with major depression that has been in remission for at least 3 months may be eligible for this study. Candidates must be between 18 and 50 years of age and right-handed. They are interviewed about their medical and psychiatric history, current emotional state and sleep pattern, and family history of psychiatric disorders. Screening also includes psychiatric interviews and rating scales, neuropsychological tests, physical examination, electrocardiogram (EKG), and blood, urine, and saliva tests. Women have their menstrual phase determined by a blood test and home urine ovulation test kit. The study involves two clinic visits in which participants undergo tryptophan depletion and magnetic resonance imaging (MRI). Subjects arrive at the NIH Clinical Center in the morning after fasting overnight. They fill out questionnaires have a blood sample drawn, and then take 74 capsules that contain a mixture of amino acids found in the diet. At one visit they are given capsules that contain a balanced mixture of amino acids one would normally eat in a day; at the other visit, some of the capsules contain lactose instead of tryptophan, causing tryptophan depletion. At 2 p.m. participants fill out the same questionnaires they completed at the beginning of the day and have another blood sample drawn. Then they do a computerized test in the MRI scanner. MRI uses a magnet and radio waves to obtain pictures of the brain. For the test, subjects lie on a narrow bed that slides into the cylindrical MRI scanner. They are asked to press a button in response to words associated with different emotions that appear on a screen. Arterial spin labeling - a test that uses magnetism to measure blood flow in different areas of the brain-is also done during the procedure. After the scan, subjects eat a meal and then return home. DNA from the participants' blood samples is also examined to try to better understand the genetic causes of depression. Some of the white cells from the samples may also be grown in the laboratory so that additional studies can be done later. ...