Lipid accumulation and dendritic cell dysfunction in cancer

Professional antigen presenting cells, dendritic cells (DC) are responsible for initiation and maintenance of immune responses. Here, we report that a substantial proportion of DCs in tumor-bearing mice and cancer patients have increased levels of triglycerides. Lipid accumulation in DCs was caused by increased uptake of extracellular lipids due to up-regulation of scavenger receptor A. DCs with high lipid content were not able to effectively stimulate allogeneic T cells or present tumor-associated antigens. DCs with high and normal lipid levels did not differ in expression of MHC and co-stimulatory molecules. However, lipid-laden DCs had reduced capacity to process antigens. Pharmacological normalization of lipid levels in DCs with an inhibitor of acetyl-CoA carboxylase restored the functional activity of DCs and substantially enhanced the effects of a cancer vaccine. These findings support the regulation of immune responses in cancer by manipulation of lipid levels in DCs

Development of an educational research software with advisory role in the clinicobiochemical evaluation of amenorrhea

Introduction: Amenorrhea is a symptom of a variety of disorders and dysfunctions. Historically, there have been many practical difficulties associated with the diagnosis of amenorrhea due to the complex nature of the ovaries, pituitary gland and hypothalamus. Purpose: To develop a free, simple stand alone educational research software (ERS) to assist the education of clinicians and laboratorians (or undergraduate students) with regard to the clinicobiochemical evaluation of amenorrhea. Μaterials and methods: The software was designed using: a) Microsoft Windows as operating system, b) C# .NET (4.0) as software component (plug-in), and c) C# (C Sharp) as (object-oriented) programming language. It can be distributed on Compact Disk (CD) and be run on any Personal Computer (PC) on Windows. Results: The developed (ERS) -which we have called ERSA v.1.0 - does not require comprehensive skills and expertise in computers. Its educational benefits (common reasons for use) include activating motivation, stimulating recall of the prerequisite material, providing learning guidance and feedback (interactivity), usability outside timetabled course, and competency assessment. Conclusions: The free ERSA v.1.0 could be a practical digital teaching tool for supporting the clinicobiochemical education. Future research should continue so as to evaluate and improve its accuracy, appropriateness, and usability by healthcare students or professionals

Oxidized LDL, serum oxidizability and serum lipid levels in patients with breast or ovarian cancer

Objectives: The aim of this study was to evaluate the extent of oxidative stress in patients with breast or ovarian cancer by analyzing the magnitude of serum oxidizability and the involvement of oxidized low-density lipoproteins (oxLDL) in the disease. Design and methods: The study was conducted on 32 patients diagnosed with breast or ovarian cancer but who had not undergone any kind of treatment and 30 healthy individuals of similar age. The evaluation of oxidative stress was assessed by: (a) the ex-vivo susceptibility of serum lipids to oxidation and (b) the detection of oxLDL and anti-oxLDL autoantibodies. Total cholesterol, LDL-cholesterol and HDL-cholesterol were co-estimated. Results: The results indicated that the levels of oxLDL were increased among both breast and ovarian cancer patients as compared to the control subjects. Additionally in patients with breast cancer, serum total cholesterol, LDL-cholesterol, anti-oxLDL antibodies and the maximal rate of diene formation (RA), the index of oxidizable components load, were increased in comparison to controls. There is statistically significant evidence that serum oxLDL levels are associated with increased risk of breast and ovarian cancer. Conclusions: The findings exhibit a correlation between oxLDL and malignancy, supporting the contribution of oxidative stress to carcinogenesis and the possible involvement of oxLDL in the process of malignancy. The clinical evaluation of the oxLDL measurement is under investigation. © 2007 The Canadian Society of Clinical Chemists

Oxidized LDL, serum oxidizability and serum lipid levels in patients with breast or ovarian cancer

Objectives: The aim of this study was to evaluate the extent of oxidative stress in patients with breast or ovarian cancer by analyzing the magnitude of serum oxidizability and the involvement of oxidized low-density lipoproteins (oxLDL) in the disease. Design and methods: The study was conducted on 32 patients diagnosed with breast or ovarian cancer but who had not undergone any kind of treatment and 30 healthy individuals of similar age. The evaluation of oxidative stress was assessed by: (a) the ex-vivo susceptibility of serum lipids to oxidation and (b) the detection of oxLDL and anti-oxLDL autoantibodies. Total cholesterol, LDL-cholesterol and HDL-cholesterol were co-estimated. Results: The results indicated that the levels of oxLDL were increased among both breast and ovarian cancer patients as compared to the control subjects. Additionally in patients with breast cancer, serum total cholesterol, LDL-cholesterol, anti-oxLDL antibodies and the maximal rate of diene formation (RA), the index of oxidizable components load, were increased in comparison to controls. There is statistically significant evidence that serum oxLDL levels are associated with increased risk of breast and ovarian cancer. Conclusions: The findings exhibit a correlation between oxLDL and malignancy, supporting the contribution of oxidative stress to carcinogenesis and the possible involvement of oxLDL in the process of malignancy. The clinical evaluation of the oxLDL measurement is under investigation. © 2007 The Canadian Society of Clinical Chemists

Serum oxidizability, total antioxidant status and albumin serum levels in patients with aneurysmal or arterial occlusive disease

Objectives: Oxidative stress is involved in the pathophysiology of atherosclerosis. The aim of the present study was to estimate the extent of oxidative stress in patients with aneurysmal and arterial occlusive disease (AAOD) by analyzing the magnitude of serum oxidizability, total antioxidant status and serum antioxidants and to evaluate their potential clinical significance. Design and methods: The study was conducted on 47 patients with AAOD and 49 healthy individuals. Oxidative stress was assessed by: a) copper-induced lipid oxidation described in terms of "lag-time" (tLAG) and "maximal rate of accumulation of absorbing products" (RA) and b) the measurement of serum total antioxidant status (TAS) and hydrophilic serum antioxidants (albumin, uric acid, transferrin, bilirubin). LDL-cholesterol and HDL-cholesterol were also estimated. Results: A decrease of tLAG and albumin levels in patients as compared to controls was observed. tLAG was negatively correlated with RA in both patients and controls. RA and LDL-cholesterol did not differ between the two groups. HDL-cholesterol was decreased in patients in comparison to controls. There is statistically significant evidence that low albumin serum levels are associated with increased risk of AAOD. Conclusions: The results support the involvement of oxidative stress in AAOD. Significant alterations in serum oxidizability were found in patients with AAOD and low albumin serum levels were correlated with the disease. Clinical evaluation of both findings needs further investigation. © 2008 The Canadian Society of Clinical Chemists

Effects of pulsed electric fields on DNA of human lymphocytes

The effects of pulsed electric fields of low frequency (50 Hz) on DNA of human lymphocytes were investigated. The influence of additional external factors, such as hydrogen peroxide (H2O2) and gamma-irradiation, as well as the repair efficiency in these lymphocytes, was also evaluated. The comet assay, a very sensitive and rapid method for detecting DNA damage at the single cells level was the method used. A significant amount of damage was observed after exposure to the electric fields, compared to the controls. After 2 h incubation at 37 degrees C, a proportion of damage was repaired. H2O2 and gamma-irradiation increased the damage to lymphocytes exposed to pulsed electric fields according to the dose used, while the amount of the repair was proportional to the damage