Young MF (2003) Bone matrix proteins: their function, regulation, and relationship to osteoporosis. Osteoporos Int 14 Suppl 3: S35–42. pmid:12730768 Schultz M, Parzinger H, Posdnjakov DV, Chikisheva TA, Schmidt-Schultz TH (2007) Oldest known case of metastasizing prostate carcinoma diagnosed in the skeleton of a 2,700-year-old Scythian king from Arzhan (Siberia, Russia). Int J Cancer 121: 2591–2595. pmid:17918181 GAGs are very important to the infectious processes of various viral, bacterial, fungal, and parasitic pathogens. The mechanisms by which these pathogens utilize GAGs to promote virulence vary based on the unique GAGs expressed in each organ system. [6] Pathogens that invade through the skin provide many examples of how GAGs are targeted to promote dermal infection. Waddington RJ, Embery G, Last KS (1989) Glycosaminoglycans of human alveolar bone. Arch Oral Biol 34: 587–589. pmid:2512903 After a bit of experimenting with all sorts of gags, I’ve come to my all-time favorite one in the form of this simplest ball gag.

Embery G, Hall R, Waddington R, Septier D, Goldberg M (2001) Proteoglycans in dentinogenesis. Crit Rev Oral Biol Med 12: 331–349. pmid:11603505

Results

This time was no different. We started with our usual foreplay involving ropes and bondage and I started getting pretty horny. That went on for some time until he stopped and asked me if I was his little cumslut and I screamed “YES”!

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Orgel JP, Eid A, Antipova O, Bella J, Scott JE (2009) Decorin core protein (decoron) shape complements collagen fibril surface structure and mediates its binding. PLoS One 4: e7028. pmid:19753304 All other GAGs require additional modification steps that take place in and around the Golgi apparatus, including sulfation of functional groups by the action of the sulfate donor compound 3`-phosphoadenosine-5`-phosphosulfate (PAPS). The availability of PAPS for sulfation of GAGs significantly affects the biosynthetic rate of production of sulfated GAGs [4]. The sulfated GAGs synthesized in the Golgi apparatus undergo covalent linkage to anchor proteins known as proteoglycans (PGs). The tethering process for the GAGs heparin/heparan sulfate, chondroitin sulfate, and dermatan sulfate occurs through a serine amino acid residue present on the protein core that connects to a common tetrasaccharide linker between the GAG and PG. Keratan sulfate is the only sulfated GAG that is not linked to a PG protein core by this mechanism and is instead linked by various other compounds depending on the subtype of keratan sulfate, described in further detail below. [3]

Schmidt-Schultz TH, Schultz M (2005) Intact growth factors are conserved in the extracellular matrix of ancient human bone and teeth: a storehouse for the study of human evolution in health and disease. Biol Chem 386: 767–776. pmid:16201872 Kjellen L, Lindahl U (1991) Proteoglycans: structures and interactions. Annu Rev Biochem 60: 443–475. pmid:1883201 Chondroitin sulfate is historically known for its clinical use as a disease-modifying osteoarthritis drug (DMOAD). Clinical trials have documented its potential for symptomatic pain relief as well as the structure-modifying effect in osteoarthritis (OA) based on radiographic joint findings. [12] There are multiple mechanisms by which chondroitin sulfate is responsible for these clinical effects. The pain-relieving properties of chondroitin sulfate in OA relate to its anti-inflammatory properties that cause attenuation of the nuclear factor-kappa-B (NF-kappa-B) pathway that is overactive in OA. [13]

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