Restricted matrilineal gene flow and regional differentiation among Atlantic salmon (Salmo salar L.) populations within the Bay of Fundy, eastern Canada.

Matrilineal phylogenetic divergence among Atlantic salmon stocks of the Bay of Fundy in south eastern Canada is investigated. Sequence variation in two regions of the mitochondrial ND1 gene, encompassing 710 base pairs, is described for 168 salmon from 11 rivers. Mean overall haplotype and nucleotide diversity (h and pi) observed are 0.5014 and 0.00095, respectively. Nested clade analysis (NCA) and molecular analysis of variance (AMOVA) both point to highly restricted gene flow among rivers and show the haplotype distribution to be geographically structured. Variation among predefined regions of the Bay (16%) is greater than among populations within these regions (14%) The main regional differentiation occurs between rivers of the geographically isolated inner Minas Basin and those elsewhere in the Bay. Differentiation most probably reflects the pattern and nature of the historical processes associated with post-glacial colonisation of the area by salmon following the last Pleistocene glacial maximum c. 180,00 yrs BP.

Increases in bone mineral density after discontinuation of daily human parathyroid hormone and gonadotropin-releasing hormone analog administration in women with endometriosis.

Intermittent PTH administration increases spinal bone mineral density (BMD) and prevents bone loss from the hip and total body in young women treated with a long acting GnRH analog for endometriosis. To establish whether these beneficial effects on BMD persist after PTH administration is discontinued, we remeasured BMD and biochemical markers of bone turnover in 38 women with endometriosis who had been treated with a GnRH analog alone (nafarelin acetate; 200 microg, intranasally, twice daily; n = 23; group 1) or who had received nafarelin plus human PTH-(1-34) (40 microg/day, s.c.; n = 15; group 2) for 6-12 months 1 yr after therapy was completed. Cyclic menstrual function returned promptly after nafarelin therapy was discontinued. In group 1, BMD increased significantly at all sites [P < 0.001 for the anterior-posterior (AP) and lateral spine; P = 0.014 for the femoral neck; P = 0.004 for the trochanter], except the proximal radius (P = 0.065) and total body bone density (P = 0.069) after nafarelin therapy was stopped. In group 2, BMD increased significantly at the AP spine (P < 0.001), lateral spine (P = 0.012), femoral neck (P = 0.002), and trochanter (P = 0.029) after nafarelin therapy was stopped. BMD of the spine in the AP projection increased more in group 2 and than in group 1 after therapy was stopped (P = 0.045). Despite these increases after discontinuation of nafarelin therapy, BMD was still significantly below baseline values at the AP spine (P < 0.001) and femoral neck (P = 0.006) and tended to be lower than baseline values at the trochanter (P = 0.057) and total body (P = 0.101) at the end of the 1-yr follow-up period in group 1. In contrast, BMD was significantly above baseline values at the AP and lateral spine (P < 0.001) sites and was similar to baseline values at the other skeletal sites at the end of the 1-yr follow-up period in group 2. Bone turnover returned to baseline values in both groups when therapy was stopped. We conclude that the beneficial effects of PTH on bone persist in women who regain cyclic menstrual function. Although part of the increases in BMD are probably due to restoration of ovarian function, additional increases in BMD most likely represent a further anabolic effect of PTH on bone that is not detected until after PTH administration is stopped.

Prevention of estrogen deficiency-related bone loss with human parathyroid hormone-(1-34): a randomized controlled trial.

CONTEXT: Short-term intermittent administration of parathyroid hormone (PTH) prevents bone loss from the spine in women treated with a gonadotropin-releasing hormone (GnRH) analog. However, the effects of a longer period of PTH administration on bone mass in estrogen-deficient women, particularly on the hip and on cortical bone of the total body, are unknown. OBJECTIVE: To determine whether more prolonged PTH administration can prevent estrogen deficiency bone loss from the hip, spine, and total body in young women with endometriosis receiving GnRH analog (nafarelin acetate) therapy. DESIGN: Randomized controlled trial. SETTING: General Clinical Research Center of a tertiary care, university-affiliated hospital. PATIENTS: Forty-three women between the ages of 21 and 45 years with symptomatic endometriosis. INTERVENTION: Nafarelin alone (200 microg intranasally twice daily) or nafarelin plus human parathyroid hormone-(1-34) (hPTH-[1-34]) (40 microg subcutaneously daily). MAIN OUTCOME MEASURES: The primary end points were bone mineral density (BMD) of the anterior-posterior and lateral spine, femoral neck, trochanter, radial shaft, and total body at 12 months of treatment. RESULTS: In the women who received nafarelin alone, the mean (SEM) BMDs of the anterior-posterior spine, lateral spine, femoral neck, trochanter, and total body were 4.9% (0.6%) (P<.001), 4.9% (0.8%) (P<.001), 4.7% (1.1%) (P<.001), 4.3% (0.9%) (P<.001), and 2.0% (0.6%) (P= .003) lower than at baseline after 12 months of therapy. In contrast, coadministration of hPTH-(1-34) increased BMD of the anterior-posterior spine by 2.1% (1.1%) (P=.09) and lateral spine by 7.5% (1.9%) (P=.002) and prevented bone loss from the femoral neck, trochanter, and total body, despite severe estrogen deficiency. Radial shaft BMD did not change significantly in either group. Serum bone-specific alkaline phosphatase and osteocalcin concentrations and urinary excretion of hydroxyproline and deoxypyridinoline increased 2-fold to 3-fold during the first 6 to 9 months of therapy in the women who received nafarelin plus hPTH-(1-34) and then declined. Changes in urinary deoxypyridinolone excretion were strongly predictive (r= 0.85) of changes in spinal BMD in the women who received nafarelin plus hPTH-(1-34). CONCLUSIONS: Parathyroid hormone prevents bone loss from the proximal femur and total body and increases lumbar spinal BMD in young women with GnRH analog-induced estrogen deficiency.

Sonohysterography: a technique for endometrial evaluation.

Sonohysterography involves the instillation of sterile saline under continuous sonographic visualization to assess the endometrial cavity. The technique is most useful for evaluating women with fertility problems, postmenopausal bleeding, or an abnormal endometrial interface as seen at baseline sonography. The procedure is performed with saline instilled into the endometrial cavity through a 5-F pediatric feeding tube or a hysterosalpingography or insemination catheter. In the normal uterus, the endometrium appears symmetric, surrounding the anechoic, saline-distended endometrial cavity. Adhesions appear as bridging bands of tissue that distort the uterine cavity or as very thin, undulating membranes, best seen at real-time examination. An intracavitary polyp is seen surrounded by anechoic fluid, with the point of attachment and thickness of the stalk clearly demonstrated. The location of leiomyomas can be determined: Intramural lesions do not distort the endometrial cavity, whereas submucosal lesions often do, with the overlying normal layer of endometrium clearly seen. In women with abnormal bleeding, focal areas of asymmetric endometrial thickening can be identified. Sonohysterography allows differentiation of intracavitary, endometrial, and submucosal abnormalities without the use of ionizing radiation or contrast agents.

Achieving dose reduction in lumbar spine radiography.

Conventional lumbar spine examinations are performed by placing the patient in the supine position. The alternative prone position is less commonly used. In this study, researchers measured entrance skin exposure for both supine and prone positioning techniques and the radiation dose to the eyes, thyroid, ovaries, testes and bone marrow. Compared with the AP projection, the PA projection produced a moderately higher bone marrow dose (28%), but resulted in a slightly reduced dose (17%) to the thyroid and greatly reduced doses (200+%) to the eyes, ovaries, uterus and testes. The PA projection also produced an ESE 52% lower than the AP projection. Results suggest an advantage to using prone positioning for lumbar spine examinations.