Background: The mature mouse oocyte contains the full complement of maternal proteins required for fertilization, reprogramming, zygotic gene activation (ZGA), and the early stages of embryogenesis. However, due to limitations of traditional proteomics strategies, only a few abundantly expressed proteins have yet been identified. Our laboratory applied a more effective strategy: one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D SDS-PAGE) and reverse-phase liquid chromatography tandem mass spectrometry (RP-LC-MS/MS) were employed to analyze the mature oocyte proteome in depth. Results: Using this high-performance proteomic approach, we successfully identified 625 different proteins from 2700 mature mouse oocytes lacking zona pellucidae. This is the largest catalog of mature mouse oocyte proteins compiled to date. According to their pattern of expression, we screened 76 maternal proteins with high levels of mRNA expression both in oocytes and fertilized eggs. Many well-known maternal effect proteins were included in this subset, including MATER and NPM2. In addition, our mouse oocyte proteome was compared with a recently published mouse embryonic stem cell (ESC) proteome and 371 overlapping proteins were identified. Conclusion: This proteomics analysis will be a valuable resource to aid in the characterization of important maternal proteins involved in oogenesis, fertilization, early embryonic development and in revealing their mechanisms of action.

Background: This study analyzed the clinical data and general information of breast cancer patients who were admitted by the Affiliated Hospital of Nantong University and underwent lumpectomy, followed by sentinel lymph node biopsy (SLNB) to investigate the effect of tumor location on the sentinel lymph node (SLN) detection rate, obtain a clear understanding of the SLNB procedure and further promote the use of this procedure in the local area. Methods: This study involved a total of 118 patients who were diagnosed with breast cancer and admitted by the Affiliated Hospital of Nantong University for lumpectomy and SLNB between July 2015 and June 2019. An analysis was conducted to explore the role of tumor location in the detection of SLNs. Results: Tumor location was associated with the success rate of post-lumpectomy SLNB. In the case of tumor location in the upper outer quadrant (UOQ) of the breast near the axilla, the SLN detection rate was relatively low. In contrast, when a tumor occurred in any of the other quadrants or the UOQ next to the areola, the tumor location had no significant impact on the SLN detection rate. SLNB indicated that 102 out of the 118 patients had SLNs, with the detection rate of 86.4%. Particularly, for patients whose tumors were located in the UOQ near their axillae, the SLN detection rate was 30% (3/10). As to tumor location in other quadrants or the UOQ next to the areola, the SLN detection rate was up to 90.8% (99/109). Conclusions: The performance of post-lumpectomy SLNB is associated with tumor location. SLNB is recommended when the tumor site lies in the upper inner/lower outer/lower inner quadrants (UIQ/LOQ/LIQ) of the breast or the UOQ next to the areola. If the SLNB result turns out to be negative, there is no need to perform axillary lymph node dissection (ALND). For tumor location in the UOQ of the breast, especially when it is near the axilla, SLNB is not a favorable option after lumpectomy. It is recommended that the patient receive a core needle biopsy (CNB) before SLNB.

Erratum to clinical value of postoperative sentinel lymph node biopsy