Distinguishing between endocrine disruption and non-specific effects on endocrine systems.

The endocrine system is responsible for growth, development, maintaining homeostasis and for the control of many physiological processes. Due to the integral nature of its signaling pathways, it can be difficult to distinguish endocrine-mediated adverse effects from transient fluctuations, adaptive/compensatory responses, or adverse effects on the endocrine system that are caused by mechanisms outside the endocrine system. This is particularly true in toxicological studies that require generation of effects through the use of Maximum Tolerated Doses (or Concentrations). Endocrine-mediated adverse effects are those that occur as a consequence of the interaction of a chemical with a specific molecular component of the endocrine system, for example, a hormone receptor. Non-endocrine-mediated adverse effects on the endocrine system are those that occur by other mechanisms. For example, systemic toxicity, which perturbs homeostasis and affects the general well-being of an organism, can affect endocrine signaling. Some organs/tissues can be affected by both endocrine and non-endocrine signals, which must be distinguished. This paper examines in vitro and in vivo endocrine endpoints that can be altered by non-endocrine processes. It recommends an evaluation of these issues in the assessment of effects for the determination of endocrine disrupting properties of chemicals. This underscores the importance of using a formal weight of evidence (WoE) process to evaluate potential endocrine activity.

Ultrasound and ultrasound-related techniques in endocrine diseases.

Ultrasound examination has become essential to evaluate morphology and size of several endocrine glands and detect the presence of lesions within these organs. Nevertheless, with the recent advances of ultrasound technology, we have opportunity to correlate the echostructure of thyroid, ovary, testis, parathyroids, etc. to their function. Thus, the ultrasound systems are in-office essential instruments for many clinical specialists. Herein we presented the most updated information about the use of ultrasound in specific endocrine-related issues, such as thyroid, parathyroid, adrenal gland, and testicle.

Usefulness of F-18 FDG-PET in detection of multiple endocrine tumors with duodenal carcinoid.

In a 76-year-old woman in whom hypercalcemia had been followed, whole body fluorodeoxyglucose positron emission tomography (FDG-PET) scan detected hypermetabolic areas in the left lower region of the thyroid gland, pancreas tail, and duodenum. CT, MR, biopsy, and surgery were performed and parathyroid adenoma, pancreatic gastrinoma, and duodenal carcinoid were diagnosed. Fluorine-18 (F-18) FDG-PET may be useful for diagnosis of multiple endocrine tumors with duodenal carcinoid.