Oxidative Stress and DNA Damage Markers in Colorectal Cancer.

Oxidative stress (OS) and inflammation are known to play an important role in chronic diseases, including cancer, and specifically colorectal cancer (CRC). The main objective of this study was to explore the diagnostic potential of OS markers in patients with CRC, which may translate into an early diagnosis of the disease. To do this, we compared results with those in a group of healthy controls and assessed whether there were significant differences. In addition, we explored possible correlations with the presence of tumors and tumor stage, with anemia and with inflammatory markers used in clinical practice. The study included 80 patients with CRC and 60 healthy controls. The following OS markers were analyzed: catalase (CAT), reduced glutathione (GSH) and oxidized glutathione (GSSG) in serum; and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and F2-isoprotanes in urine (F2-IsoPs). Tumor markers (CEA and CA 19.9), anemia markers (hemoglobin, hematocrit and medium corpuscular volume) and inflammatory markers (leukocytes, neutrophils, N/L index, platelets, fibrinogen, C-reactive protein, CRP and IL-6) were also determined. Comparison of means between patients and controls revealed highly significant differences for all OS markers, with an increase in the prooxidant markers GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and a decrease in the antioxidant markers CAT and GSH. Tumor and inflammatory markers (except CRP) correlated positively with GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and negatively with CAT and GSH. In view of the results obtained, OS markers may constitute a useful tool for the early diagnosis of CRC patients.

Influence of Loading Conditions on the Mechanical Performance of Multifilament Coreless UHMWPE Sutures Used in Orthopaedic Surgery.

This work studies the influence of loading velocity and previous cyclic loading history on the stiffness and strength of a multifilament coreless ultra-high-molecular-weight polyethylene (UHMWPE) surgical suture. Thread samples (n = 8) were subjected to a load-to-failure test at 0.1, 0.5, 1, 5, and 10 mm/s without previous loading history and after 10 cycles of loading at 1-10 N, 1-30 N, and 1-50 N. The experimental data were fitted to mathematical models to compute the stress-strain relation and the strength of the suture. The bilinear model involving two stress-strain ratios for low- and high-strain intervals was the best fit. The ratio in the low-strain range rose with loading speed, showing mean increases of 5.9%, 6.5%, 7.9%, and 7.3% between successive loading speeds. Without a previous loading history, this ratio was less than half than that at high strain. However, 10 cycles of 1-30 N or 1-50 N significantly increased the stress-strain ratio at a low strain level by 135% and 228%, respectively. The effect persisted after 2 min but vanished after 24 h. No influence was found on the suture strength. In conclusion, the stiffness of the studied suture was influenced by the strain level, loading velocity, and recent cyclic loading history. Conversely, the suture strength was not affected.

[Factors that influence interdepartmental referrals between Surgical Departments and Internal Medicine]. / Factores que influyen en la solicitud de interconsultas a medicina interna por los servicios quirúrgicos.

INTRODUCTION: To analyse the long term outcome of the age and comorbidity of patients admitted to Surgical Departments, the number of referrals to Internal Medicine made by these Departments, and to assess whether there are seasonal variations and the call/reject effect. MATERIAL AND METHODS: We compared the age, Charlson Comorbidity Index (CCI), and the number of referrals made by Traumatology, General Surgery and Urology of patients discharged in 2000, with those discharged in 2007. Seasonal variations and the call/reject effect were studied by analysing all the interdepartmental referrals made by all the surgical departments from the year 2000 to 2007. RESULTS: Age increased by 5.6% between 2000 and 2007, the CCI by 5.8%, and interdepartmental referrals by 60%. Interdepartmental referrals decreased in July and August, whilst they increased in January, February, June and October, up to 64% more in January, although with variations of almost 50% in the same month. We detected differences of up to 68.2% in the referrals requested to different physicians. CONCLUSIONS: We observed a sharp increase in the requests for referral to Internal Medicine by Surgical Departments of our hospital, which is not explained by the increase in admissions to these Departments, and which could be associated with the increase in age and comorbidity of their patients. Requests for interdepartmental referral have marked monthly variations and also as regards the Consulting Physician.