Circulating Omentin-1 levels and altered iron balance in chronic haemodialysis patients.

BACKGROUND: Iron deficiency is highly prevalent among patients undergoing chronic haemodialysis (HD) but its correct identification is often problematic as common biomarkers of iron status, such as transferrin saturation (TSAT) and ferritin, can be altered by inflammation or malnutrition. METHODS: In this pilot multicentre study, we aimed at evaluating circulating levels of Omentin-1, a novel fat depot-specific adipokine that is also involved in iron regulation, in a cohort of 85 chronic HD patients with relation to their iron status. RESULTS: Omentin-1 levels in HD were statistically higher than in healthy controls (P = 0.03) and there was a significant, growing trend in all iron parameters across Omentin-1 tertiles (P < 0.001). Compared with patients with optimal iron status, Omentin-1 levels were lower in subjects categorized according to TSAT ≤20% or serum ferritin ≤200 µg/L (both P < 0.001) and even more reduced in 19 patients (22%) simultaneously displaying low levels of both markers (P < 0.001). In this latter group, Omentin-1 levels increased in parallel to all other iron markers after iron correction by i.v. supplementation. At multivariate regression analyses, ferritin (ß = 0.71; P < 0.001) and TSAT (ß = 0.32; P = 0.03) remained the sole independent predictors of Omentin-1 levels. This biomarker also showed a remarkable diagnostic capacity at receiver operating characteristic analyses in identifying iron-depleted HD patients according to a criterion of TSAT ≤20% [area under the curve (AUC) 0.827], ferritin ≤200 µg/L (AUC 0.863) or low levels of both parameters (AUC 0.907). CONCLUSIONS: Findings obtained indicate that Omentin-1 is somewhat involved in iron balance regulation and might be a candidate biomarker for diagnosing and managing altered iron conditions in HD patients.

Immunocryosurgery is a safe and feasible treatment for basal cell carcinoma and Bowen disease in renal transplant recipients.

Keratinocyte skin carcinomas (squamous cell carcinoma, basal cell carcinoma [BCC], Bowen disease [BD]) inflict significant morbidity and constitute a treatment challenge in renal transplant recipients (RTR). Immunocryosurgery has shown efficacy >95% in the treatment of BCC and BD in immunocompetent patients. The present study evaluated the safety, feasibility and efficacy, of immunocryosurgery in the treatment of BCC and BD in a series of RTR. During a 3-year period, biopsy-confirmed cases of BCC and BD were treated with a standard immunocryosurgery cycle (5 weeks daily imiquimod and a session of cryosurgery at day 14). Safety was evaluated by comparing graft function markers between immunocryosurgery treated RTR patients and matched controls. Ten BCC (8 nodular, 1 basosquamous, 1 superficial; diameter 6-14 mm; mean 9.2 mm) and nine BD disease lesions in nine patients (7 men, 2 women; age range: 54-70 years, mean: 62.1 years) were treated with immunocryosurgery and followed-up for two to 5 years. Five BCC were located on the "H area" of the face. No patient showed clinical or laboratory signs of transplant dysfunction during treatment or follow-up. Seven out of 10 BCC lesions cleared completely after one 5-week immunocryosurgery cycle, two cleared after repeat and intensified treatment cycles and one responded only partially (clearance rate: 90%). Seven out of nine BD lesions cleared after one 5-week immunocryosurgery cycle and one lesion after two cycles (clearance rate: 88.9%). In conclusion, immunocryosurgery is a safe, feasible and effective minimally invasive treatment alternative to standard surgical modalities for BCC and BD in RTR.

Side reactions in the SPPS of Cys-containing peptides.

Alkylation of sensitive amino acids during synthesis of biologically important peptides is a common and well-documented problem in Fmoc-based strategy. Herein, we probed for the first time an unexpected S-alkylation of Cys-containing peptides that occur during the final TFA cleavage of peptides from the Wang solid support. Through a battery of approaches (NMR, UV and LC-MS) the formed by-product was assigned as the alkylation of the cysteine sulfydryl group by the p-hydroxyl benzyl group derived from the acidic Wang linker decomposition. Factors affecting this side reaction were monitored and a protocol that minimizes the presence of the by-product is reported.