The impact of inflammation on bone mass in children

Bone is a dynamic tissue. Skeletal bone integrity is maintained through bone modeling and remodeling. The mechanisms underlying this bone mass regulation are complex and interrelated. An imbalance in the regulation of bone remodeling through bone resorption and bone formation results in bone loss. Chronic inflammation influences bone mass regulation. Inflammation-related bone disorders share many common mechanisms of bone loss. These mechanisms are ultimately mediated through the uncoupling of bone remodeling. Cachexia, physical inactivity, pro-inflammatory cytokines, as well as iatrogenic factors related to effects of immunosuppression are some of the common mechanisms. Recently, cytokine signaling through the central nervous system has been investigated for its potential role in bone mass dysregulation in inflammatory conditions. Growing research on the molecular mechanisms involved in inflammation-induced bone loss may lead to more selective therapeutic targeting of these pathological signaling pathways

The Pan-Thames EPS study : treatment and outcomes of encapsulating peritoneal sclerosis

Original article can be found at : http://ndt.oxfordjournals.org/ Copyright Oxford University Press [Full text of this article is not available in the UHRA]Background: Encapsulating peritoneal sclerosis (EPS) is a disease process that can occur as a complication of peritoneal dialysis (PD). The aim of this study was to make a general assessment of the clinical features, diagnosis, management and outcome of PD-related EPS cases from London and South-East England. Methods: Questionnaires were sent to 11 PD units in March 2007; cases were identified retrospectively. Outcome data on surviving patients were collected in March 2008. Results: A total of 111 patients were identified; the mean time on PD was 82 months (range 8–247). Mortality increased with length of time on PD, being 42% at 10 years (n = 17). Twelve patients had no previous peritonitis episodes, 28 had one previous episode, 30 had two previous episodes and 33 had three or more previous episodes. Of the patients with PD details available, 41/63 were high (>0.81) transporters and 44/71 had ultrafiltration 1 l/24 h and a few had significant residual renal function. Sixty-five (59%) patients had their PD discontinued prior to diagnosis (51 HD; 14 transplanted). CT scans were performed on 91 patients and laparotomy on 47 patients. Drug treatment consisted of tamoxifen, immunosuppression or both. The median survival was 15 months in patients treated with tamoxifen (n = 17), 12 months in patients treated with immunosuppression (n = 24) and 21 months in patients who received both (n = 13), against 13 months (n = 46) in patients who received no specific treatment. Adhesionolysis was performed in 5 patients, and 39 patients were given parenteral nutrition. The overall mortality was 53% with a median survival of 14 months and a median time to death of 7 months. Conclusion: This is one of the largest cohorts of patients with EPS in the literature. Long-term survival occurred in over 50%, regardless of the various treatments strategies undertaken by the centres.Peer reviewe

The calcilytics Calhex-231 and NPS 2143 and the calcimimetic Calindol reduce vascular reactivity via inhibition of voltage-gated Ca(2+) channels.

The present study investigates the effect of commonly used negative and positive allosteric modulators of the calcium-sensing receptor (CaSR) on vascular reactivity. In wire myography studies, increasing [Ca(2+)]o from 1mM to 6mM induced concentration-dependent relaxations of methoxamine-induced pre-contracted rabbit mesenteric arteries, with 6mM [Ca(2+)]o producing almost complete relaxation. [Ca(2+)]o-induced relaxations were attenuated in the presence of the calcilytics Calhex-231 and NPS 2143, and abolished by the removal of the endothelium. In addition to their calcilytic effects, Calhex-231 and NPS 2143 also produced concentration-dependent inhibitions of methoxamine- or KCl-induced precontracted tone, which were unaffected by removal of the endothelium and unopposed in the presence of the calcimimetic Calindol. In vessels with depleted Ca(2+) stores, contractions mediated by Ca(2+) influx via voltage-gated Ca(2+) channels (VGCCs) were inhibited by Calhex231. In freshly isolated single rabbit mesenteric artery smooth muscle cells, Calhex-231 and NPS 2143 inhibited whole-cell VGCC currents. Application of Calindol also inhibited methoxamine- and KCl-induced pre-contracted tone, and inhibited whole-cell VGCC currents. In conclusion, in addition to their CaSR-mediated actions in the vasculature, Calhex-231, NPS 2143 and Calindol reduce vascular contractility via direct inhibition of VGCCs