No abstract

Antler growth is highly co-ordinated, so that trabecular bone and antler skin (velvet) develop together, at a rapid rate and in a manner reminiscent of their development in the fetus. Parathyroid hormone-related peptide (PTHrP) is expressed in both bone and skin, and is therefore a candidate to effect co-ordination between these tissues. The aim of this study was to localize the expression of PTHrP and its principal receptor, the parathyroid hormone/parathyroid hormone-related peptide receptor (PTH/PTHrPR), in antler ("spiker") of one-year-old red deer. Using immunohistochemistry and in situ hybridization, intense and overlapping expression of PTHrP and its receptor was seen in developing osseocartilaginous structures and in the underlying layers of velvet epidermis. PTHrP was located on both the cell surface and within the nuclei. Our results strongly suggest that PTHrP, acting via the PTH/PTHrPR and possibly other intracrine mechanisms, plays a central role in the co-ordinated regulation of cell division and differentiation of developing antler bone and skin.

Objective: The ANCHOR program offered buprenorphine treatment to people who inject drugs engaged in hepatitis C (HCV) treatment at a Washington, DC harm reduction organization. This analysis describes the program model and outcomes of the opioid care continuum at 1 year. Methods: Primary outcomes were initiation of buprenorphine and retention in care, defined by an active buprenorphine prescription at given time points. Secondary outcomes included treatment interruptions, reasons for treatment noninitiation and termination, buprenorphine and opiate use, and HIV risk behaviors. Buprenorphine and opiate use were measured by urine toxicology screens and HIV risk behavior was quantified using a validated survey. Results: Of 67 patients receiving HCV treatment not on opioid agonist therapy at baseline, 96% (n ¼ 64) were interested and 73% (n ¼ 49) initiated buprenorphine. Retention was 82% (n ¼ 40), 65% (n ¼ 32), and 59% (n ¼ 29) at months 1, 6, and 12, respectively. Retention at 12 months was associated with selfreported engagement in routine medical care (P < 0.01), but was not associated with gender, stable housing, past opioid agonist therapy, or past overdose. Among retained patients, urine screens positive for opioids were 73% (n ¼ 29), 56% (n ¼ 18), and 79% (n ¼ 23) at months 1, 6, and 12. There was a significant mean decrease in HIV risk-taking behavior scores over the treatment period, primarily driven by reduced injection frequency. Conclusions: Patients engaged in HCV treatment at a harm reduction organization showed a high rate of initiation of buprenorphine treatment, with retention comparable to other treatment settings. Although most patients continued using opioids on treatment, there was a reduced frequency of injection drug use, a significant driver of OUD-related risk. These data support the use of low-threshold buprenorphine access alongside HCV treatment to reduce morbidity and mortality in people with OUD.