Field resistance to wheat stem rust in durum wheat accessions deposited at the USDA National Small Grains Collection.

Wheat stem rust, caused by Puccinia graminis f. sp. tritici, is a re-emerging disease, posing a significant threat to durum wheat production worldwide. The limited number of stem rust resistance genes in modern cultivars compels us to identify and incorporate new effective genes in durum wheat breeding programs. We evaluated 8,245 spring durum wheat accessions deposited at the USDA National Small Grains Collection (NSGC) for resistance in field stem rust nurseries in Debre Zeit, Ethiopia and St. Paul, MN (USA). A higher level of disease development was observed at the Debre Zeit nursery compared with St. Paul, and the effective alleles of Sr13 in this nursery did not display the level of resistance observed at the St. Paul nursery. Four hundred and ninety-one (∽6%) accessions exhibited resistant to moderately susceptible responses after three field evaluations at Debre Zeit and two at St. Paul. Nearly 70% of these accessions originated from Ethiopia, Mexico, Egypt, and USA. Eight additional countries, namely Portugal, Turkey, Italy, Canada, Chile, Australia, Syria, and Tunisia contributed to 19% of the resistant to moderately susceptible entries. Among the 491 resistant to moderately susceptible accessions, 53.8% (n = 265) were landraces, and 28.4% (n = 139) and 11.4% (n = 55) were breeding lines and cultivars, respectively. Breeding lines and cultivars displayed a higher level and frequency of resistance than the landraces. We concluded that a large number of durum wheat accessions from diverse origins deposited at the NSGC can be exploited for diversifying and improving stem rust resistance in wheat.

Evidence of a tumour suppressive function of E2F1 gene in human breast cancer.

BACKGROUND: The E2F family of transcription factors are key regulators of genes involved in cell cycle progression, cell fate determination, DNA damage repair and apoptosis. E2F1 is unique in that it contributes both to the control of cellular proliferation and cellular death. Furthermore, unlike other E2Fs, E2F1 responds to various cellular stresses. This study aimed to examine the level of mRNA expression of E2F1 gene in normal and malignant breast tissue and correlate the level of expression to tumour stage. MATERIALS AND METHODS: One hundred and twenty-seven breast cancer tissue and 33 normal tissues were analyzed. Levels of transcription of E2F1 were determined using real-time quantitative PCR, normalized against CK19. Levels of expression were analyzed against TNM stage, nodal involvement, tumour grade and distant metastasis. RESULTS: The levels of E2F1 mRNA were lower in malignant tissues. They declined further with increasing TNM stage. This became statistically significant when TNM stages 3 and 4 were compared to TNM stages 1 and 2 disease (TNM1 vs. TNM3 p = 0.032; TNM1 vs. TNM4 p = 0.032; TNM2 vs. TNM3 p = .019; TNM2 vs. TNM4 p = 0.021). The levels of E2F1 also fell with increasing tumour grade, when comparing grade 2 and 3 with grade 1, however, the differences were not statistically significant. CONCLUSION: These results are highly suggestive of the role of E2F1 as a tumour suppressive gene in human breast cancer.

Breast papillomas: current management with a focus on a new diagnostic and therapeutic modality.

Breast papilloma is a term that describes an intraductal papillary configuration of the mammary epithelium on macroscopic or microscopic examination. It includes solitary intraductal papillomas, multiple papillomas, papillomatosis, and juvenile papillomatosis (JP).Recent advances in mammary ductoscopy (MD) have raised new possibilities in the diagnosis and treatment of breast papillomas. This technique represents an important diagnostic adjunct in patients with pathological nipple discharge (PND) by allowing direct visualisation and biopsy of intraductal lesions and guiding duct excision surgery. Treatment of breast papillomas often entails surgical duct excision for symptomatic relief and histopathological examination. Recently, more conservative approach has been adapted. MD-assisted microdochectomy should be considered the procedure of choice for a papilloma-related single duct discharge. Furthermore, there is increasing evidence that MD has the potential to reduce the number of duct excision procedures and minimise the extent of surgical resection. Imaging-guided vacuum-assisted core biopsy can be diagnostic and therapeutic for papillomas seen on mammography and/or ultrasound. Patients with multiple papillomas do have an increased risk of developing cancer and should be kept under annual review with regular mammography (preferably digital mammography) if treated conservatively. Magnetic resonance (MR) can be also used in surveillance in view of its high sensitivity. Because the risk is small, long term and affects both breasts, long-term follow-up is more appropriate than prophylactic mastectomy. Patients who prove to have solitary duct papilloma have insufficient increase in the risk of subsequent malignancy to justify routine follow-up.