Prolonged Remission of Cushing\u27s Disease Following Bromocriptine Therapy

A 33-year-old woman developed hypercorticism of fulminant onset following delivery of a full-term, normal child. An ectopic hormone-producing neoplasm was excluded by extensive studies. Pituitary dependent hypercorticism of intermediate lobe origin was suggested on the basis of onset following pregnancy, failure of Cortisol suppression by high-dose dexamethasone, hyperresponsiveness of prolactin to thyrotropin-releasing hormone stimulation, and reduction in adrenocorticotropin titers following oral administration of bromocriptine. Initial remission of disease achieved with bromocriptine was followed by recurrence on discontinuation of the agent. However, complete remission which occurred following a prolonged course of bromocriptine has persisted for a total of 22 months

Pregnancy Following Sequential Bromocriptine Therapy in a Hyperprolactinemic Subject

Regular menses were maintained in a 26-year-old woman with a prolactinoma by sequential bromocriptine therapy given for either five or 14 days of the menstrual cycle. She conceived promptly when desired

The comparative metabolism of cadmium, mercury and zinc as environmental contaminants in the freshwater mussel, Margaritifera margaritifera

The uptake, tissue distribution and retention patterns of cadmium, mercury and zinc were examined in the freshwater mussel, Margaritifera margaritifera. All three of these heavy metals are found in the environment. Both cadmium and mercury are toxic at low environmental concentrations. Zinc may also be toxic at low concentrations but is also a required microelement in plants and animals. The mussels were maintained in separate solutions containing radioisotopes of these metals at 14.5°C. The uptake was followed for 39 to 80 days of chronic exposure, at which time a near equilibrium was reached in most experiments. At this point all animals were placed in uncontaminated water. Half of them were sampled at intervals to determine changes in tissue distribution. The remainder were regularly counted to determine the pattern of retention. An Armac liquid scintillation whole-body counter was used for all determinations. The tissue distribution. was remarkably constant over separate studies lasting from 67 to 150 days. Multicomponent retention patterns were observed for each metal. The percent of original whole-body activity remaining after 81 days was 87% for methylmercuric chloride, 69% for mercuric nitrate, 76% for cadmium chloride and 57% for zinc chloride. Retention studies were terminated after approximately 81-150 days. The long term retention components for cadmium chloride, methylmercuric chloride, mercuric nitrate and zinc chloride revealed biological half-lives of 835, 860, 194 and 103 days, respectively. The inhibition of zinc uptake in mussels was demonstrated when 2.0 ppm cadmium was added to the experimental solution. This level of cadmium also proved toxic to the mussels with a median survival time of 88 hours. When the cadmium concentration was doubled (4.0 ppm) the median survival time was reduced to 61 hours

MALIGNANT SOMATOSTATINOMA PRESENTING WITH DIABETIC KETOACIDOSIS

High circulating levels of somatostatin (SRIF) were detected in a patient with a metastatic tumour after development of diabetic ketoacidosis (DKA). Fasting insulin and C-peptide levels were markedly suppressed, but plasma glucagon was not suppressed below normal. Progressive cachexia ensued; at autopsy a poorly differentiated non-small cell neuroendocrine carcinoma metastatic to liver was found. Small gallstones were noted. Electron microscopy of tumour tissue showed neurosecretory granules and tonofilament bundles. Immunohis-tochemical staining of tumour cells was diffusely positive for carcinoembryonic antigen, bombesin-like immunoreactivity, and calcitonin with focal immuno-reactivity for SRIF, serotonin, neuron-specific enolase, chromogranin, and epithelial membrane antigen. Column chromatography of plasma and tumour extract revealed five or more peaks of material with SRIF-like immunoreactivity (SRIF-LI): predominantly SRIF-28 and intermediates in tumour extract, and SRIF-14 and an intermediate between SRIF-28 and SRIF-14 in plasma. DKA in this case of somatostatinoma syndrome may reflect differential effects of tumour production of larger molecular weight SRIF forms on insulin and glucagon secretion.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75579/1/j.1365-2265.1987.tb00817.x.pd

A Pulsed-air Model of Blue Whale B Call Vocalizations

Blue whale sound production has been thought to occur by Helmholtz resonance via air flowing from the lungs into the upper respiratory spaces. This implies that the frequency of blue whale vocalizations might be directly proportional to the size of their sound-producing organs. Here we present a sound production mechanism where the fundamental and overtone frequencies of blue whale B calls can be well modeled using a series of short-duration (\u3c1 \u3es) wavelets. We propose that the likely source of these wavelets are pneumatic pulses caused by opening and closing of respiratory valves during air recirculation between the lungs and laryngeal sac. This vocal production model is similar to those proposed for humpback whales, where valve open/closure and vocal fold oscillation is passively driven by airflow between the lungs and upper respiratory spaces, and implies call frequencies could be actively changed by the animal to center fundamental tones at different frequency bands during the call series