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We investigated the role of carbohydrates in blastocyst attachment to the uterine epithelium. Le(y) (Fuc alpha 1-->2Gal beta 1-->4[Fuc alpha 1-->3] GlcNAc) was localized by indirect immunofluorescence to the surface of the mouse blastocyst and uterine epithelium. Western blot analysis showed that Le(y) is carried on many uterine glycoproteins in both pregnant and nonpregnant females; however, new species were detected on Day 4 postcoitum (p.c.) coincident with the onset of uterine receptivity. The function of Le(y) in implantation was tested by injecting monoclonal antibody (mAb) directly into the uterine lumen on Days 3-5 p.c. The effects of intrauterine injections on implantation were scored by comparing the number of viable embryos to the number of CL on Day 10 p.c. Injection of purified anti-Le(y) IgM into the uterine lumen on the afternoon of Day 4 significantly inhibited implantation. This effect was dose-dependent and was obtained during a narrow time window, from 87 to 93 h p.c. Inhibition of implantation was not observed in contralateral uterine horns injected with saline, nor was it observed in uterine horns injected with other anti-carbohydrate mAbs. We conclude that binding of anti-Le(y) to the blastocyst or luminal epithelium masks a ligand involved in implantation. Although the mechanism of inhibition is unknown, we show that Le(y) can interact with another oligosaccharide (H) that has been described as a possible uterine ligand for blastocyst attachment. We hypothesize that Le(y) and H form carbohydrate-carbohydrate interactions that promote close apposition of cell surface membranes during an early step in implantation.

Summary Effects of different state/phase transitions (temperature fluctuations) on quality attributes of mango cubes during frozen storage were investigated. Temperature of frozen mango was modulated from −65 °C to different states, namely, rubbery state (T>Tm′), partially freeze‐concentrated state (Tg″

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Changes in the quality of frozen mango cuboids were investigated during long-term glassy state storage with and without osmotic dehydration pretreatment. The mango cuboids were dehydrated in mixed solutions (sucrose: glucose: fructose in a ratio of 3.6:1:3) of different concentrations (30, 40, and 50% (wt/wt)) prior to freezing and then stored at -55°C (in the glassy state) for 6 months. The results revealed that compared with the untreated samples, osmotic pretreatment decreased total color difference (reduced by 15.6-62.3%), drip loss (reduced by 8.2-29.5%) and titration acidity (reduced by 1.3-9.4%), while increasing hardness (increased by 48.8-82.3%), vitamin C content (increased by 72.5-120.6%) and total soluble solids (increased by 21.8-53.7%) of frozen mangoes after 6 months. Dehydration with a sugar concentration of 40% was considered as the optimal pretreatment condition. In addition, a storage temperature of -55°C provided better retention of quality than rubbery state storage at -18°C. With prolonged storage time, the quality of frozen mangoes continued to change, even in the glassy state. However, the changes in quality of the osmotic-dehydrated samples were less than those of the untreated samples. The current work indicates that osmotic pretreatment and glassy state storage significantly improved the quality of frozen mangoes during long-term storage.

The glycolipid composition of human myometrium and endometrium was examined at various stages of maturation and reproduction. The major neutral glycolipids of both myometrium and endometrium were identified by high-performance thin-layer chromatography as globo-series glycolipids, Gb3 and Gb4. The major acidic glycolipids (gangliosides) were identified similarly as GM3 and GD3, with lesser amounts of GM1, GD1a, and GT1b. During pregnancy, GD3 expression declined in both myometrium and endometrium, whereas GM3 expression increased. Reciprocal changes in GM3/GD3 expression were mirrored by appropriate changes in the glycosyltransferases required for their synthesis; alpha 2----3sialyltransferase activity increased approximately 3-fold during pregnancy, while alpha 2----8sialyltransferase activity declined to about 20%. The results focus attention on the glycolipids of uterine tissues, their regulation, and their possible role in reproduction and fertility.