Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Stomach Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed ; methods

ObjectiveTo construct a human ovarian cancer cell line SKOV3 （SK-Luc-EGFP） stably co-expressing luciferase （Luc） and enhanced green fluorescent protein （EGFP） and to explore its application in ovarian cancer research both in vitro and in vivo. MethodsThe recombinant plasmid pCDH-Luc-T2A-EGFP-Puro was constructed by introducing a Luc-T2A-EGFP fusion gene fragment amplified by Overlap PCR into plasmid vector. The three-plasmid lentivirus packaging system was transfected into HEK 293T cells and the viral supernatant was harvested to infect SKOV3 cells. SK-Luc-EGFP cell line with the highest fluorescence intensity of EGFP was obtained by puromycin selection and flow cytometry assessment， and the Luc expression of the cell line was subsequently validated by in vitro bioluminescent assay. SK-Luc-EGFP cells were further explored for the following applications： distinguishing SK-Luc-EGFP cells from non-tumor cells in ascites by flow cytometry and confocal microscopy； visualizing adhesion of SK-Luc-EGFP cells to mesothelial cells or omentum by fluorescence microscopy； monitoring process of SK-Luc-EGFP tumorigenesis by in vivo bioluminescence imaging. ResultsA recombinant lentiviral expression plasmid pCDH-Luc-T2A-EGFP-Puro was constructed and packaged into lentiviral particles that were then transfected into SKOV3 cells to generate SK-Luc-EGFP cell line. The purity of SK-Luc-EGFP cells based on EGFP expression was 100% as validated by fluorescence microscopy and flow cytometry； SK-Luc-EGFP cells could be visually distinguished from non-tumor cells in ascitic fluid by flow cytometry and confocal imaging. Moreover， Luc expression in SK-Luc-EGFP cells was verified by in vitro bioluminescence assay， and a linear relationship with a correlation coefficient of 0.997 9 was found between cell number and the bioluminescent signal. Adhesion of SK-Luc-EGFP cells to mesothelial cells was directly observed by fluorescence imaging in in vitro adhesion assay； peritoneal adhesion of SK-Luc-EGFP cells to omentum was also observed after intraperitoneal （i.p.） injection of SK-Luc-EGFP cells in nude mice； in the peritoneal metastasis mouse model established by i.p. injection of SK-Luc-EGFP cells， monitoring of tumorigenesis process was achieved by in vivo bioluminescence imaging. ConclusionSK-Luc-EGFP cell line is a useful tool for investigating ovarian cancer in vitro and in vivo.

A highly sensitive and selective bioluminescent probe for hydrazine (BPH) was designed, synthesized and evaluated for detection of hydrazine in vitro and in vivo. BPH was designed to include a specific recognition group (acetyl) of hydrazine at an appropriate modification site of the optical reporter hydroxyluciferin (D-luciferin), which showed excellent performance both in selectivity and sensitivity to hydrazine. The results showed that the bioluminescent probe BPH developed in this study is an innovative and widely applicable tool for detecting hydrazine in complex natural environment or in animals.

OBJECTIVE: To investigate the mechanistic basis for the attenuation of bone degeneration by edible bird's nest (EBN) in ovariectomized rats. METHODS: Forty-two female Sprage-Dawley rats were randomized into 7 groups (6 in each group). The ovariectomized (OVX) and OVX + 6%, 3%, and 1.5% EBN and OVX +estrogen groups were given standard rat chow alone, standard rat chow +6%, 3%, and 1.5% EBN, or standard rat chow +estrogen therapy (0.2mg/kg per day), respectively. The sham-operation group was surgically opened without removing the ovaries. The control group did not have any surgical intervention. After 12 weeks of intervention, blood samples were taken for serum estrogen, osteocalcin, and osteoprotegerin, as well as the measurement of magnesium, calcium abd zinc concentrations. While femurs were removed from the surrounding muscles to measure bone mass density using the X-ray edge detection technique, then collected for histology and estrogen receptor (ER) immunohistochemistry. RESULTS: Ovariectomy altered serum estrogen levels resulting in increased food intake and weight gain, while estrogen and EBN supplementation attenuated these changes. Ovariectomy also reduced bone ER expression and density, and the production of osteopcalcin and osteorotegerin, which are important pro-osteoplastic hormones that promote bone mineraliztion and density. Conversely, estrogen and EBN increased serum estrogen levels leading to increased bone ER expression, pro-osteoplastic hormone production and bone density (all P<0.05). CONCLUSION EBN could be used as a safe alternative to hormone replacement therapys for managing menopausal complications like bone degeneration.