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The structural properties of pelleted prepubertal Sertoli cells (pre-culture pelleted cells) from 19-day-old rats and of similar cells cultured for 7 days were compared with Sertoli cells from the intact animal (testis tissue from 19- and 26-day-old rats, the in vivo groups). Sertoli cells from freshly isolated pellets and those cultured for 7 days were similar in cell and nuclear volumes to their in vivo counterparts. Cell volumes, organelle volumes, and organelle volume densities of newly isolated Sertoli cells were similar to those of sectioned cells taken from the 19-day-old in vivo group, indicating that the procedure for isolation does not grossly alter Sertoli cells. Mean height of cells cultured for 7 days was significantly lower than that of cells from intact animals at 19 and 26 days of age. In vivo, Sertoli cells of 26-day-old animals displayed increased organelle volumes and organelle surface areas compared with those from 19-day-old animals; volume densities and surface densities remained relatively constant, indicating that in vivo, organelle growth is in proportion to growth of the cell. Most organelle volume and surface densities were not significantly different when 19-day-old in vivo cells and pre-culture pelleted cells were compared. Many organelle volume and surface density values were significantly less in cells grown in culture for 7 days as compared to freshly isolated pelleted cells. After 7 days of culture, most Sertoli cell organelles were significantly less in both volume density and surface density, as compared to the in vivo cell groups (19 or 26 day). This indicates that in vitro the organelles do not develop in proportion to the growth of the cell. After 7 days in culture, the absolute volumes and surface areas of the organelles remained generally unchanged as compared to cells from 19-day-old animals. The data show that Sertoli cells grow in volume in vitro like their in vivo counterparts; however, their subcellular features, although well maintained, do not develop in proportion to the cell. This suggests that short-term cultures are a more ideal system in which to study biochemical responses. Also, cultured prepubertal Sertoli cells are most appropriately used to study prepubertal Sertoli cell function. This is the first study to quantify developmental changes in Sertoli cell structure in vivo as well as to compare them with cellular changes occurring in vitro.

MSPurpose: Tobacco use continues to be the single most preventable cause of death and disease in the United States. A paradigm shift is needed in physician assistant (PA) education to address tobacco dependence as a chronic, relapsing disease requiring patient education, counseling, treatment, and follow-up. Methods: A national study was conducted to assess the existing tobacco dependence education currently offered in US PA programs. An established tobacco dependence curriculum survey was revised and mailed to the 141 accredited PA programs in the United States during the 2008-2009 academic year. The survey asked respondents to report the following with regard to tobacco dependence education content in their PA program: (1) Perceived self-efficacy and barriers; (2) Medical topics covered and minutes spent; (3) Evaluation of students' competency level; (4) Tobacco courses, topics, and resources used; and (5) Level of tobacco-cessation competency expected upon graduation. Results: A total of 79 surveys were returned (56% response rate). Though, on average, over 827 minutes (14 hours) were devoted to tobacco dependence education curriculum, most minutes (223 minutes) were spent on the health effects of tobacco use, with only 42 minutes spent on cessation counseling, 55 minutes on medications, and 13 minutes on integrating tobacco-cessation into clinical practice. Conclusions: PA educators have the unique opportunity to affect tobacco-related morbidity and mortality. The present study demonstrates that PA instructors are more than adequately teaching students about tobacco use. However, it is not clear if students are being adequately taught how to assist patients to quit using tobacco.

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AAPA POSTER SESSION ABSTRACT AAPA POSTER SESSION ABSTRACTH yponatremia occurs in 18% of long-term care residents and is the most common electrolyte disturbance. The syndrome of inappropriate antidiuretic hormone (SIADH) secretion affects 30% of all patients with hyponatremia and is the most common cause of euvolemic hyponatremia.In this case, a 90-year-old man who lived in a long-term care facility and had a history of smoking was evaluated for shortness of breath, productive cough, hemoptysis, progressive fatigue, and signifi cant weight loss. On physical examination, the patient revealed increased respiratory effort and peripheral edema in both lower extremities. Past medical history was signifi cant for chronic obstructive pulmonary disease (COPD), atrial fi brillation treated with amiodarone, and hypothyroidism. Laboratory results revealed severe hyponatremia (124 mEq/L compared with a normal range of 135 to 145 mEq/L), hypotonic serum osmolality (260.5 mOsm/kg compared with a normal range of 275 to 295 mOsm/kg), and inappropriately elevated urine sodium (95 mEq/L; the value should be less than 30 mEq/L in a patient with hyponatremia). Chest radiography revealed an enlarging perihilar left upper lobe mass suspicious for malignancy, along with a loculated, encapsulated pleural effusion. CT scan supported the chest radiograph fi ndings.Small-cell lung carcinoma was suspected in this patient because it is highly associated with tobacco use and often is associated with paraneoplastic syndromes, SIADH being the most common. A diagnosis of SIADH caused by potential lung malignancy was made. SIADH occurs in 11% to 15% of patients with small-cell lung carcinoma due to ectopic production of antidiuretic hormone by the tumor itself. In addition, this patient's SIADH was thought to be due to amiodarone use, older age, and COPD. Due to the patient's age, no invasive procedures were planned, and a careful medical management plan was devised.The patient's use of amiodarone was a key component. A class III antiarrhythmic, amiodarone has sodium channel modifying effects on neural and renal tissue, which could induce SIADH. Older adults with comorbidities are at greatest risk for this effect. The only defi nitive treatment of amiodarone-induced SIADH is to discontinue its use; however, this may not be possible in some patients.Pulmonary diseases such as COPD also can cause SIADH due to renal vasoconstriction and antidiuresis in response to hypercapnia. The renal response eventually leads to hyponatremia due to water retention. Idiopathic SIADH is also a common cause of hyponatremia in older adults. Age-related changes in renal handling of sodium and water are thought to be contributing factors.The clinical picture of SIADH is most commonly that of euvolemia. However, this patient's diagnosis was complicated by probable heart failure with peripheral edema (another cause of hyponatremia). In SIADH alone, natriuretic peptides are not affected, so patients are able to maintain euvolemia. However, this is not the case in patients ...