Complex carbohydrates in the human cervix were studied histochemically using lectins conjugated to horseradish peroxidase and correlated procedures. Stratified squamous epithelium of the exocervix and columnar epithelium of the endocervix in some, but not all specimens showed staining for terminal alpha-N-acetyl-D-galactosamine, alpha-D-galactose, beta-D-galactose and alpha-L-fucose. The staining for alpha-N-acetylgalactosamine and alpha-galactose, the terminal sugars in blood group A and B antigens respectively, corresponded to a large extent with ABO blood type. One exception was the lack of staining for terminal alpha-N-acetylgalactosamine in endocervical secretions in three of nine blood type A patients. A second exception was the staining for terminal alpha-galactose in endocervical secretions in about half of blood type O and A specimens. The type and amount of glycoprotein formed by endocervical columnar cells differed according to location in superficial compared with deep portions of the glands and according to location at the junction with exocervix compared with the more internal regions. Staining of endothelial cells for blood group A and B antigens was confined to subjects of blood type A and B respectively, although three of nine type A specimens showed no lectin reactivity for group A antigen. Endothelial cells evidenced affinity for Ulex europeus I agglutinin demonstrative of fucose in all specimens. Mast cells disclosed lectin affinity consistent with the presence of terminal or internal mannose or N-acetylglucosamine residues. Two blood type O specimens were examined with conjugated lectins at the ultrastructural level. Secretory granules stained for content of terminal alpha-galactose, beta-galactose and fucose. These results support and concur with biochemical studies of complex carbohydrates in human cervical tissues. They reveal, in addition, the location of the blood group antigens in the human exocervix and endocervix and the marked heterogeneity among endocervical columnar cells in glycoprotein production.

Utilizing carbon dioxide (CO2) to make polycarbonates through the ring‐opening copolymerization (ROCOP) of CO2 and epoxides valorizes and recycles CO2 and reduces pollution in polymer manufacturing. Recent developments in catalysis provide access to polycarbonates with well‐defined structures and allow for copolymerization with biomass‐derived monomers; however, the resulting material properties are underinvestigated. Here, new types of CO2‐derived thermoplastic elastomers (TPEs) are described together with a generally applicable method to augment tensile mechanical strength and Young's modulus without requiring material re‐design. These TPEs combine high glass transition temperature (Tg) amorphous blocks comprising CO2‐derived poly(carbonates) (A‐block), with low Tg poly(ε‐decalactone), from castor oil, (B‐block) in ABA structures. The poly(carbonate) blocks are selectively functionalized with metal‐carboxylates where the metals are Na(I), Mg(II), Ca(II), Zn(II) and Al(III). The colorless polymers, featuring <1 wt% metal, show tunable thermal (Tg), and mechanical (elongation at break, elasticity, creep‐resistance) properties. The best elastomers show >50‐fold higher Young's modulus and 21‐times greater tensile strength, without compromise to elastic recovery, compared with the starting block polymers. They have wide operating temperatures (−20 to 200 °C), high creep‐resistance and yet remain recyclable. In the future, these materials may substitute high‐volume petrochemical elastomers and be utilized in high‐growth fields like medicine, robotics, and electronics.

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Complex carbohydrates and cations have been localized by cytochemical methods in mitochondria of mammalian leukocytes, hepatocytes and oyster gill epithelium. Glycoconjugate of acidic nature was visualized with the dialyzed iron method in or on the outer membrane and inner boundary membrane and in the outer intermembrane space but not on the membranes of cristae or in the intracristate space, or matrix. Sulfated glycoconjugate was demonstrated with the high iron diamine method in a similar distribution and in, on, or between, membranes of cristae as well. Intermittent aggregates of dialyzed iron and high iron diamine stained material were often found in the outer intermembrane space. The periphery of isolated rat liver mitochondria also stained with a Concanavalin A horseradish peroxidase technique, indicating the presence of macromolecules, presumably glycoproteins containing mannose or glucose. The distribution of antimonate reactive cation in mitochondria of leukocytes resembled that of the acidic glycoconjugate, indicating binding of cations to anionic groups of the latter. The complex carbohydrates and cations demonstrated cytochemically in mitochondria are considered in relation to previous biochemical studies.

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