Androgen Dependent Mammary Gland Virilism in Rats Given the Selective Estrogen Receptor Modulator LY2066948 Hydrochloride

A selective estrogen receptor modulator (SERM) is a nonsteroidal compound with tissue specific estrogen receptor (ER) agonist or antagonist activities. In animals, SERMs may produce morphologic changes in hormonally-sensitive tissues like the mammary gland. Mammary glands from female rats given the SERM LY2066948 hydrochloride (LY2066948) for 1 month at ≥ 175 mg/kg had intralobular ducts and alveoli lined by multiple layers of vacuolated, hypertrophied epithelial cells, resembling in part the morphology of the normal male rat mammary gland. We hypothesized that these SERM-mediated changes represented an androgen-dependent virilism of the female rat mammary gland. To test this hypothesis, the androgen receptor antagonist flutamide was co-administered with LY2066948 (175 mg/kg) to female rats for 1 month. Female rats given SERM alone had hyperandrogenemia and the duct and alveolar changes described here. Flutamide cotreatment did not affect serum androgen levels but completely blocked the SERM-mediated mammary gland change. In the mouse, a species that does not have the sex-specific differences in the mammary gland observed in the rat, SERM treatment resulted in hyperandrogenemia but did not alter mammary gland morphology. These studies demonstrate that LY2066948 produces species-specific, androgen-dependent mammary gland virilism in the female rat.

The reversible effects of raloxifene on luteinizing hormone levels and ovarian morphology in mice

Raloxifene is a selective estrogen receptor modulator that has estrogen agonist effects on bone and serum lipids and estrogen antagonist effects on breast and uterine tissues. This study assessed the effects of raloxifene hydrochloride (HCl) treatment on circulating luteinizing hormone (LH) levels and ovarian morphology in sexually mature, 15-week-old, female CD-1 mice. Mice were maintained on diets providing average daily doses of 0 or 233 mg/kg raloxifene for 2 weeks (Study 1) or 0, 7.9, or 236 mg/kg raloxifene for 4 weeks (Study 2). At the end of the treatment period, blood samples were collected every 2 hours for 24 h in Study 1 (5 mice per group) and at 10:00 a.m. and 10:00 p.m. in Study 2 (8 mice per group). Serum LH levels were measured by radioimmunoassay. Ovarian histomorphology was evaluated in the 10 mice per group (Study 1) and the 8 mice per group (Study 2). For the reversibility phase (Study 2), mice were fed untreated diets for 3 weeks; serum LH levels and ovarian histomorphology were then assessed. Raloxifene treatment at 233 mg/kg/day for 2 weeks (Study 1) significantly elevated circulating LH levels by 4- to 7-fold compared with control. Raloxifene-treated mice had elevated LH levels sustained over the 24-h sampling period and did not exhibit the preovulatory LH surge evident in some control mice at the 4:00 p.m., 6:00 p.m., and 8:00 p. m. time points. Mice treated with 236 mg/day raloxifene for 4 weeks (Study 2) had elevated LH levels (4.4-fold compared to control), whereas mice exposed to 7.9 mg/kg/day raloxifene had a slight, nonsignificant increase in LH (2-fold compared to control). In both dose groups, LH levels were indistinguishable from controls 3 weeks after raloxifene treatment was discontinued. The ovaries in six of the eight mice treated with 7.9 mg/kg/day raloxifene had dilated and/or anovulatory follicles. One mouse in this group had a single hemorrhagic follicle; however, corpora lutea distribution was normal, indicating that ovulation was occurring. Raloxifene-treated mice in Study 1 and mice treated with a comparable raloxifene dose (236 mg/day) in Study 2 had histomorphological changes in the ovary indicative of arrested follicular maturation, including anovulatory hemorrhagic follicles, some developing follicles, and very few corpora lutea. At the end of the reversibility phase, hemorrhagic follicles were no longer evident and follicular maturation and corpora lutea distribution were normal. Raloxifene treatment in mice produces a dose-dependent, sustained elevation in serum LH levels and is associated with changes in ovarian follicular morphology. These changes are reversible upon discontinuation of raloxifene treatment.

Serial pHi measurement as a predictor of mortality, organ failure, and hospital stay in surgical patients

Intestinal ischemia is a common condition in critically ill patients and has been postulated to play a role in the development of organ failure and death. This has resulted in the recent interest in monitoring gastric intramucosal pH (pHi) in critically ill patients to provide earlier evidence of inadequate resuscitation, cardiogenic dysfunction, or sepsis. Several reports have indicated that low pHi values obtained during the initial 24 to 48 hours of intensive care unit (ICU) admission were associated with the development of organ failure and death. The purpose of this study was to assess the predictive value of serial pHi measurements obtained throughout the entire ICU admission. A retrospective analysis of critically ill trauma, burn, and surgical patients who had frequent pHi determinations during ICU treatment was performed. When stratified by pHi values, there were no significant differences in length of stay, organ dysfunction, or mortality. Our findings suggest that serial pHi determinations obtained beyond the early critical care period are less reliable predictors of poor outcome.

Endoscopic saphenous vein harvest in infrainguinal bypass surgery

BACKGROUND

Autologous greater saphenous vein is considered to be the optimal material for peripheral arterial reconstruction and coronary artery revascularization. We describe a new endoscopic technique of saphenous vein harvest in infrainguinal arterial bypass surgery.

METHODS

A retrospective analysis of 64 infrainguinal bypass procedures was performed comparing the standard open technique of saphenous vein harvesting with a new less invasive endoscopic technique.

RESULTS

There were no differences in age, gender, indications for surgery, or proximal or distal anastomosis between the two groups. There were also no significant differences in early wound complications, early patency, and transfusion requirements. In the endoscopic group, length of operation was longer (189 versus 158 minutes; P <0.005), length of stay was shorter (5.2 versus 8.1 days; P <0.05), and postoperative day of discharge was also less (3.3 versus 5.5 days; P <0.01).

CONCLUSIONS

Our findings indicate that endoscopic saphenectomy is technically feasible, leads to earlier discharge from the hospital, and leads to increased operative time. Most importantly, the procedure can be performed safely without subjecting the patient to increased risk.

Clinical and radiographic presentations of HIV-1 necrotizing ulcerative periodontitis

HIV-1-associated periodontal diseases have been reported in the literature for several years. Criteria for the diagnosis of these diseases have not been universally accepted, although there are numerous papers describing the clinical entity. These case reports provide clinical and radiographic evidence of a type of periodontal disease with bone and soft tissue destruction which differentiates it from "conventional" periodontal diseases found in both HIV-1-infected patients and those not infected by the virus. It is important, from both diagnostic and therapeutic aspects, for clinicians to be able to make this distinction. The appropriate use of clinical and radiographic findings is extremely helpful in the diagnosis, particularly in the case of defining HIV-1 necrotizing ulcerative periodontitis (NUP). Whether the patterns of gingival changes and bone loss described in these case reports are specific to HIV-1-seropositive persons or rather represent severe immunosuppression requires further investigation.