Haplotype diversity and population structure in cultivated and wild barley evaluated for Fusarium head blight responses.

Fusarium head blight (FHB) is a threat to barley (Hordeum vulgare L.) production in many parts of the world. A number of barley accessions with partial resistance have been reported and used in mapping experiments to identify quantitative trait loci (QTL) associated with FHB resistance. Here, we present a set of barley germplasm that exhibits FHB resistance identified through screening a global collection of 23,255 wild (Hordeum vulgare ssp. spontaneum) and cultivated (Hordeum vulgare ssp. vulgare) accessions. Seventy-eight accessions were classified as resistant or moderately resistant. The collection of FHB resistant accessions consists of 5, 27, 46 of winter, wild and spring barley, respectively. The population structure and genetic relationships of the germplasm were investigated with 1,727 Diversity Array Technology (DArT) markers. Multiple clustering analyses suggest the presence of four subpopulations. Within cultivated barley, substructure is largely centered on spike morphology and growth habit. Analysis of molecular variance indicated highly significant genetic variance among clusters and within clusters, suggesting that the FHB resistant sources have broad genetic diversity. The haplotype diversity was characterized with DArT markers associated with the four FHB QTLs on chromosome 2H bin8, 10 and 13 and 6H bin7. In general, the wild barley accessions had distinct haplotypes from those of cultivated barley. The haplotype of the resistant source Chevron was the most prevalent in all four QTL regions, followed by those of the resistant sources Fredrickson and CIho4196. These resistant QTL haplotypes were rare in the susceptible cultivars and accessions grown in the upper Midwest USA. Some two- and six-rowed accessions were identified with high FHB resistance, but contained distinct haplotypes at FHB QTLs from known resistance sources. These germplasm warrant further genetic studies and possible incorporation into barley breeding programs.

Follicle curetting at the time of oocyte retrieval increases the oocyte yield.

PURPOSE: To determine whether follicle curetting at the time of oocyte retrieval increases oocyte yield. METHODS: Retrospective review of all patients who underwent oocyte retrieval from July 1, 2003 to June 30, 2005. MAIN OUTCOME MEASURE: Number of oocytes retrieved. SECONDARY OUTCOME MEASURES: retrieval time, number of cryopreserved embryos, pregnancy rates, and incidence of ovarian hyperstimulation syndrome. RESULTS: There were no differences in patient demographics, antral follicle count, cycle stimulation characteristics, fertilization rates, embryo quantity or quality, embryo cryopreservation rates, clinical pregnancy rates, live birth rates, or ovarian hyperstimulation syndrome between the groups. Retrievals that utilized curetting took three minutes longer. Follicle curetting significantly increased the number of oocytes retrieved, 13.9 +/- 0.6 compared to 11.4 +/- 0.6 oocytes without curetting (P = 0.003). The quantity of mature oocytes was also increased with curetting (10.3 +/- 0.5 versus 8.4 +/- 0.5, P = 0.006). CONCLUSIONS: This study demonstrated that follicle curetting significantly increased oocyte yield. While it did not increase live birth rates, this increase in oocyte yield should lead to increased numbers of embryos for selection at transfer and increased embryos for cryopreservation.

Dynorphin immunoreactive fibers contact GnRH neurons in the human hypothalamus.

Dynorphin, an endogenous opioid peptide, mediates progesterone-negative feedback on gonadotropin-releasing hormone (GnRH) neurons in other species. The role of dynorphin in humans is unclear. The objective of this study was to determine if dynorphin fibers have close contacts with GnRH neurons in humans. Dual-label immunocytochemistry was performed on postmortem human hypothalamic tissue. The majority of GnRH neurons, 87.5%, had close contacts with dynorphin fibers and multiple close contacts were common, 62.5%. There were no regional differences between the hypothalamus and preoptic area in the distribution of close contacts. More close contacts were identified on the GnRH dendrites compared to the cell bodies (P < .001), but this difference was not significant when corrected for length. In conclusion, dynorphin fibers form close contacts with GnRH neurons in humans. This neuroanatomical evidence may suggest that dynorphin has effects on GnRH regulation in humans as seen in other species.

Maternal virilization due to luteoma associated with delayed lactation.

OBJECTIVE: To report on a patient with virilization during pregnancy who experienced delayed lactation secondary to elevated maternal androgens. DESIGN: Case report and review of the literature. SETTING: University hospital. PATIENT(S): A 32-year-old pregnant woman presented with virilization at 32 weeks' gestation. INTERVENTION(S): Laboratory evaluation, ultrasound examination, magnetic resonance imaging, cesarean section for fetal indication, nipple stimulation to facilitate lactation. MAIN OUTCOME MEASURE(S): Case report. RESULT(S): Postpartum normalization of serum T levels and patient ability to breastfeed exclusively after delayed initiation of lactation. CONCLUSION(S): Maternal virilization during pregnancy is rare and is often due to androgen-secreting tumors that are benign. Therefore, careful evaluation of these patients is important to avoid inadvertent oophorectomy.