Objective The aim of this study is to explore the changes of expression of integrin αvβ3 in bovine u-terine epithelial cells in vitro induced by estrogen or/and progesterone alone or in combination,and to provide a new refer-ence marker for determining bovine uterine receptivity state. Methods RT-PCR was used to analyze the transcriptional changes of αvβ3 expression in bovine endometrium treated by different concentrations of estrogen,progesterone alone or in combination. Results The expression of integrin αvβ3 reached the highest level when the culture medium was added with progesterone at the concentration of 10 -7mg/mL,and the expression of αv and β3 in the 10 -7mg/mL concentration group was significantly higher than that of the control one(P<0.05). Moreover,the expression of αv was highest in the 10 -10 mg/mL E2group,but the expression of β3 was the lowest in that one. In addition,adding with both estrogen and progester-one,the transcriptional level of integrin αvβ3 was significantly higher than that in the control one. The transcriptional level of αv in the treatment group was significantly higher than that in the control group(P<0.05),but the transcriptional level of β3 in this group was not(P>0.05). Conclusions It can be concluded that integrin αvβ3 can be used as a new poten-tial reference marker gene for detecting the bovine uterine receptive status.

Regeneration carries the idea of regrowing partially or completely a missing organ. Repair, on the other hand, allows restoring the function of an existing but failing organ. The recognition that human lungs can both repair and regenerate is quite novel, the concept has not been widely used to treat patients. We present evidence that the human adult lung does repair and regenerate and introduce different ways to harness this power. Various types of lung stem cells are capable of proliferating and differentiating upon injury driving the repair/regeneration process. Injury models, primarily in mice, combined with lineage tracing studies, have allowed the identification of these important cells. Some of these cells, such as basal cells, broncho-alveolar stem cells, and alveolar type 2 cells, rely on fibroblast growth factor (FGF) signaling for their survival, proliferation and/or differentiation. While preclinical studies have shown the therapeutic benefits of FGFs, a recent clinical trial for acute respiratory distress syndrome (ARDS) using intravenous injection of FGF7 did not report the expected beneficial effects. We discuss the potential reasons for these negative results and propose the rationale for new approaches for future clinical trials, such as delivery of FGFs to the damaged lungs through efficient inhalation systems, which may be more promising than systemic exposure to FGFs. While this change in the administration route presents a challenge, the therapeutic promises displayed by FGFs are worth the effort.