Other signs and symptoms include changes in posture and facial expression, slowed speech, poor hygiene, unkempt appearance, feelings of guilt, shame, or helplessness, diminished ability to concentrate, nihilistic thoughts, and suicidal ideation.Many experts in the field have attempted to find reliable differences between BP-I depressive episodes and episodes of major depressive disorder, but the data is inconsistent. However, some clinicians report that patients who came in with a depressive episode, but were later diagnosed as having bipolar disorder often presented with hypersomnia, increased appetite, psychomotor retardation, and a history of antidepressant-induced hypomania. Evidence also suggests that BP-II is strongly associated with atypical depression. Mood episodes with mixed features
A mixed episode is defined by the presence of a hypomanic or depressive episode that is accompanied by symptoms of the opposite polarity. This is commonly referred to as a mood episode with mixed features (e.g. depression with mixed features or hypomania with mixed features), but can also be referred to as mixed episodes or mixed states. For example, a patient with depression with mixed features may have a depressed mood, but has simultaneous symptoms of rapid speech, increased energy, and flight of ideas. Conversely, a patient with hypomania with mixed features will present with the full criteria for a hypomanic episode, but with concurrent symptoms of decreased appetite, loss of interest, and low energy.Episodes with mixed features can last up to several months.
Iobenguane, or MIBG, is an aralkylguanidine analog of the adrenergic neurotransmitter norepinephrine (noradrenaline), typically used as a radiopharmaceutical. It acts as a blocking agent for adrenergic neurons. When radiolabeled, it can be used in nuclear medicinal diagnostic and therapy techniques as well as in neuroendocrine chemotherapy treatments. It localizes to adrenergic tissue and thus can be used to identify the location of tumors such as pheochromocytomas and neuroblastomas. With iodine-131 it can also be used to treat tumor cells that take up and metabolize norepinephrine. Usage and mechanism
MIBG is absorbed by and accumulated in granules of adrenal medullary chromaffin cells, as well as in pre-synaptic adrenergic neuron granules. The process in which this occurs is closely related to the mechanism employed by norepinephrine and its transporter in vivo. The norepinephrine transporter (NET) functions to provide norepinephrine uptake at the synaptic terminals and adrenal chromaffin cells. MIBG, by bonding to NET, finds its roles in imaging and therapy. Metabolites and excretion
Less than 10% of the administered MIBG gets metabolized into m-iodohippuric acid (MIHA), and the mechanism for how this metabolite is produced is unknown. Diagnostic imaging
MIBG concentrates in endocrine tumors, most commonly neuroblastoma, paraganglioma, and pheochromocytoma. It also accumulates in norepinephrine transporters in adrenergic nerves in the heart, lungs, adrenal medulla, salivary glands, liver, and spleen, as well as in tumors that originate in the neural crest. When labelled with iodine-123 it serves as a whole-body, non-invasive scintigraphic screening for germ-line, somatic, benign, and malignant neoplasms originating in the adrenal glands.