C Phenekos

Red Cross Hospital, Athens, Athínai, Attica, Greece

Are you C Phenekos?

Claim your profile

Publications (16)51.13 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the natural course of apparently benign adrenal incidentalomas with no overt hyperfunction at diagnosis, as their clinical significance and appropriate management are still controversial. Prospective long-term follow-up study of patients with adrenal incidentalomas with periodic hormonal and morphological evaluation. A total of 77 patients with incidental adrenal masses, diameter 1.0-6.0 cm (median 2.5 cm), were submitted to a hormonal assessment of adrenal function at diagnosis. This was repeated, together with an adrenal CT scan, 12 months later and then every 12-24 months, for a period of 12-154 months (mean 62.7 +/- 31.9, median 60.0). At diagnosis, 57 patients had normal adrenal function and 20 had subclinical Cushing's syndrome. During follow-up, adrenal function remained normal in 49 patients, subclinical Cushing's syndrome was confirmed in 12, whilst intermittent subclinical autonomous cortisol hypersecretion was found in 12 patients. Overt endocrine disease was diagnosed in 4 patients (Cushing's syndrome in 2 and phaeochromocytoma in 2). A change in mass size (> or = 0.5 cm) was observed in 26 patients (enlargement in 20--including patients who developed overt hyperfunction--with no signs of malignancy and reduction in size in 6). Subclinical autonomous cortisol hypersecretion is the most frequent hormonal abnormality in patients with adrenal incidentalomas, and may be intermittent in a significant percentage of cases. Few patients develop overt endocrine disease. A growth tendency is observed in some adrenal incidentalomas without evidence of malignant transformation and occasionally can be related to development of overt hyperfunction. These findings indicate the need for periodic hormonal and morphological evaluation for several years.
    No preview · Article · May 2009 · Clinical Endocrinology

  • No preview · Article · May 2008 · Atherosclerosis Supplements
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Oxidation of lipoproteins, particularly of low-density lipoprotein (LDL), is of prime importance in the initiation and progression of atherosclerosis. The Mediterranean diet has been associated with an unexpectedly low rate of cardiovascular events. Type 2 diabetic patients are at high risk of developing atherosclerosis. Functional alterations in the endothelium, which lead to atherosclerosis, are stimulated by oxidized lipoproteins, particularly oxidized LDL. The present study investigated the effect of Greek quick casual Mediterranean-type diet (fast food Mediterranean-type diet) consumption on the resistance to oxidation in plasma from type 2 diabetic patients and healthy human subjects. Lipids from fast food Mediterranean-type foodstuffs were extracted and tested in vitro for their ability to inhibit copper (Cu2+)-induced LDL oxidation. Foodstuffs that exerted the most potent in vitro antioxidative activity were chosen for the diet of study groups. Eighteen type 2 diabetic patients (group A) and 10 healthy subjects (group B) were fed a 4-week diet contained the chosen foodstuffs, while 17 type 2 diabetic patients (group C) were kept on their regular diet that they were following before the study. Type 2 diabetic patients were treated with sulfonylureas or metformin and were under good glycemic control (hemoglobin A1C < 7%). Serum lipoproteins, triglycerides, glucose, body mass index (BMI), and plasma resistance to Cu2+-induced oxidation before and after the 4-week diet were monitored. At the beginning of the study, no statistical difference was detected in plasma resistance to Cu2+-induced oxidation between type 2 diabetic patients (groups A and C) and healthy human subjects (group B), as this was detected at a time before the oxidation products become detectable, namely, lag time. After the 4-week period on the chosen diet the lag time in groups A and B significantly increased, while it was not changed in group C. In type 2 diabetic patients lag time was increased from 57.3 +/- 13.3 minutes (mean +/- SD) to 103.8 +/- 21.8 minutes (mean +/- SD) (P < .000), while in healthy human subjects there was an increase from 58.0 +/- 8.5 minutes (mean +/- SD) to 85.7 +/- 21.8 minutes (mean +/- SD) (P < .004). In all groups, total cholesterol, high-density lipoprotein-cholesterol, LDL-cholesterol, triglycerides, glucose, and BMI were not changed. Fast food Mediterranean foodstuffs exerted antioxidant activities both in vitro and in vivo after consumption in type 2 diabetic patients and healthy human subjects. Therefore consumption of a fast food Mediterranean-type diet should contribute to prevention against cardiovascular diseases.
    Full-text · Article · Sep 2007 · Journal of Medicinal Food
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the effect of metformin plus roziglitazione (RSGMET) compared with metformin alone (MET) on glycaemic control in well-controlled Type 2 diabetes. Subjects (drug naïve or those on glucose-lowering monotherapy) were randomized (n = 526), following a 4-week placebo run-in period, to RSGMET [4 mg rosiglitazone (RSG)/500 mg MET] or MET 500 mg. From weeks 2-18, medication was escalated every 4 weeks (based on gastrointestinal tolerability), then remained at RSGMET 8 mg/2 g or MET 3 g for 14 weeks. RSGMET reduced HbA(1c) from 7.2 +/- 0.6 to 6.7 +/- 0.8% at week 32, compared with a reduction from 7.2 +/- 0.6 to 6.8 +/- 0.9% with MET (treatment difference -0.13%; P = 0.0357). More subjects achieved an HbA(1c) value of </= 6.5% at week 32 with RSGMET (51.6 vs. 43.7%), but the treatment difference was not significant (odds ratio 1.37, P = 0.0949). RSGMET produced larger reductions from baseline in mean fasting plasma glucose (adjusted difference -0.62 mmol/l, P < 0.0001), with the odds ratio of achieving a target of < 7.0 mmol/l being 2.33 (P < 0.0001). Statistically significant differences in favour of RSGMET relative to MET were seen for homeostatic model assessment (HOMA)-derived estimates of insulin sensitivity and pancreatic B-cell function, C-reactive protein (CRP), and systolic blood pressure. Overall rates of gastrointestinal adverse events (relevant to the known profile of MET) were comparable, but with a lower incidence of diarrhoea (8 vs. 18%) with RSGMET. Hypoglycaemia was reported in </= 7% subjects per group. RSGMET provided similar short-term glycaemic control to MET with greater improvements in estimates of insulin sensitivity, B-cell function and CRP, with less diarrhoea and low risk of biochemical hypoglycaemia, suggesting that early use of combination therapy may be appropriate.
    No preview · Article · Nov 2006 · Diabetic Medicine
  • [Show abstract] [Hide abstract]
    ABSTRACT: Patients with type 2 diabetes mellitus have increased risk of cardiovascular disease. Epidemiological studies have shown a correlation between diet and incidence of coronary heart disease. The aim of the study is to determine the effect of a traditional Greek Mediterranean diet on platelet aggregation induced by ADP, arachidonic acid (AA), and especially platelet-activating factor (PAF) on patients with type 2 diabetes mellitus as well as on healthy volunteers. The patients were randomized into two subgroups, A and B. The lipid extracts from traditional Greek Mediterranean-type meals were tested in in vivo for their ability to reduce PAF- or thrombin-induced platelet aggregation. The meals with the most potent anti-aggregating activity were chosen for the diet of both subgroup A and healthy subjects and consumed for a period of 28 days, whereas subgroup B kept to their regular diet that was followed before entering the study. Platelet-rich plasma was isolated before and after the diet, and the ability of platelets to aggregate under the aggregating factors was tested. One-month consumption of diet resulted in a significant reduction in PAF- and ADP-induced aggregation of platelets in both groups of healthy volunteers (PAF and ADP, P < .05) and subgroup A (PAF, P < .001; ADP, P < .05), whereas the AA-induced aggregation was not affected. No effect was observed in subgroup B, which followed the standard diet. Thus the consumption of a traditional Greek Mediterranean diet even for a short period can reduce platelet activity in patients suffering from type 2 diabetes mellitus and in healthy subjects.
    No preview · Article · Sep 2006 · Journal of Medicinal Food

  • No preview · Article · Jun 2006 · Atherosclerosis Supplements
  • V Loi · M Vertzoni · A Vryonidou · C Phenekos
    [Show abstract] [Hide abstract]
    ABSTRACT: An isocratic high-performance liquid chromatographic method with detection at 234 nm was developed, optimized and validated for the determination of testosterone in human serum. Propylparaben was used as internal standard. A Hypersil BDS RP-C18 column (150 mmx4.6 mm, 5 microm), was equilibrated with a mobile phase composed of acetonitrile and water (35:65, v/v) and having a flow rate of 1 ml/min. The elution time for testosterone and internal standard was approximately 11.6 and 9.9 min, respectively. Calibration curves of testosterone in serum were linear in the concentration range of 1-20 ng/ml. Limits of detection and quantification in serum were 0.4 and 1.1 ng/ml, respectively. Recovery was greater than 92%. Intra- and inter-day relative standard deviation for testosterone in serum was less than 2.1 and 3.9%, respectively. This method was applied to the determination of testosterone serum levels of 12 healthy males and data were correlated with data obtained using a radioimmunoassay method.
    No preview · Article · Jun 2006 · Journal of Pharmaceutical and Biomedical Analysis
  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of our work was to carry out a randomized clinical trial with a fast-food Mediterranean type diet rich in platelet activating factor (PAF) antagonist to investigate the effect on type 2 diabetics and healthy human subject's platelet aggregation. We extracted lipids from fast-food Mediterranean type foodstuffs, and tested them in vitro for their ability to inhibit or antagonize PAF towards washed rabbit platelets. We chose the foodstuffs that exerted the most potent in vitro anti-PAF activity and fed 22 healthy (group A) and 23 type 2 diabetics (group B) subjects on a diet containing the chosen foodstuffs. The 22 type 2 diabetics (group C) subjects were kept on their regular diet that was being followed before entering the study. Before and after a 4-week diet, all enrolled subjects underwent the following examinations; measurement of total cholesterol, low density lipoprotein (LDL-cholesterol), high density lipoprotein (HDL-cholesterol), triglycerides, glucose, HbA(1c), body mass index (BMI), and platelet aggregation in response to PAF, adenosine 5' diphosphate (ADP) and arachidonic acid (AA). The chosen diet significantly increased the EC(50) values of PAF and ADP to groups A and B (p<0.05). No statistical difference was observed on the EC(50) value of group C. No statistical differences were detected among Cholesterol, LDL-cholesterol, triglycerides, glucose, HBA(1c), BMI, and EC(50) for AA values, for any of the three groups. Consumption of a fast-food Mediterranean type diet rich in PAF antagonist improved platelet response of type 2 diabetics and healthy human subjects against thrombotic, inflammatory and proatherogenic factors.
    No preview · Article · Apr 2006 · Diabetes Research and Clinical Practice
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Strontium ranelate, a new oral drug shown to reduce vertebral fracture risk in postmenopausal women with osteoporosis, was studied in the Treatment of Peripheral Osteoporosis (TROPOS) study to assess its efficacy and safety in preventing nonvertebral fractures also. Strontium ranelate (2 g/d) or placebo were randomly allocated to 5091 postmenopausal women with osteoporosis in a double-blind placebo-controlled 5-yr study with a main statistical analysis over 3 yr of treatment. In the entire sample, relative risk (RR) was reduced by 16% for all nonvertebral fractures (P = 0.04), and by 19% for major fragility fractures (hip, wrist, pelvis and sacrum, ribs and sternum, clavicle, humerus) (P = 0.031) in strontium ranelate-treated patients in comparison with the placebo group. Among women at high risk of hip fracture (age > or = 74 yr and femoral neck bone mineral density T score < or = -3, corresponding to -2.4 according to NHANES reference) (n = 1977), the RR reduction for hip fracture was 36% (P = 0.046). RR of vertebral fractures was reduced by 39% (P < 0.001) in the 3640 patients with spinal x-rays and by 45% in the subgroup without prevalent vertebral fracture. Strontium ranelate increased bone mineral density throughout the study, reaching at 3 yr (P < 0.001): +8.2% (femoral neck) and +9.8% (total hip). Incidence of adverse events (AEs) was similar in both groups. This study shows that strontium ranelate significantly reduces the risk of all nonvertebral and in a high-risk subgroup, hip fractures over a 3-yr period, and is well tolerated. It confirms that strontium ranelate reduces vertebral fractures. Strontium ranelate offers a safe and effective means of reducing the risk of fracture associated with osteoporosis.
    Full-text · Article · Jun 2005 · Journal of Clinical Endocrinology & Metabolism
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: The aim of this study was to document the pattern of immune response, assessed by the measurement of both Th1 and Th2 serum cytokines, in patients suffering from autoimmune thyroid disease and toxic nodular goiter. Methods: Both Th1 and Th2 serum cytokine levels were assayed in patients suffering from Graves' disease (GD, n = 25), Hashimoto's thyroiditis (HT, n = 21), and toxic nodular goiter (TNG, n = 7) and compared with corresponding levels of 25 healthy controls. Serum concentrations of IL-2, IL-1β, INF-γ, TNF-α, IL-12, IL-15, IL-10, IL-18, IL-4 and IL-5 were assayed in fasting serum samples. Results: It was found that patients with HT had higher IL-2 serum levels (12.16 ± 0.66 pg/ml) compared to patients with TNG (9.25 ± 0.84 pg/ml), GD (7.86 ± 0.30 pg/ml) and controls (7.36 ± 0.45 pg/ml; p = 0.0001), higher INF-γ levels (7.60 ± 0.33 pg/ml) compared to patients with TNG (5.77 ± 0.55 pg/ml), GD (5.74 ± 0.24 pg/ml) and controls (5.09 ± 0.27 pg/ml; p = 0.0009), higher IL-12 levels (3.57 ± 0.19 pg/ml) compared to patients with TNG (2.57 ± 0.21 pg/ml), GD (2.48 ± 0.13 pg/ml) and controls (2.59 ± 0.23 pg/ml; p = 0.004), and higher IL-18 levels (27.52 ± 1.75 pg/ml) compared to patients with TNG (18.71 ± 2.24 pg/ml), GD (15.44 ± 1.39 pg/ml) and controls (15.16 ± 1.62 pg/ml; p = 0.0002). In contrast, patients with GD had higher serum levels of IL-4 (4.11 ± 0.33 pg/ml) compared to patients with HT (3.0 ± 0.16; p = 0.02) and higher IL-5 levels (4.22 ± 0.30 pg/ml) compared to patients with TNG (3.21 ± 0.58 pg/ml), HT (2.75 ± 0.16 pg/ml) and controls (2.0 ± 0.19 pg/ml; p = 0.0001). Patients had lower IL-1β serum levels (TNG 2.45 ± 0.20, HT 2.52 ± 0.14, GD 2.68 ± 0.12 pg/ml) compared to controls (3.6 ± 0.20 pg/ml; p = 0.008). Conclusions: The above findings suggest that a Th1 pattern of immune response characteristic of cellular immunity is dominant in HT, whereas the predominance of Th2 cytokines in GD indicates a humoral pattern of immune reaction.
    No preview · Article · Feb 2004 · NeuroImmunoModulation

  • No preview · Article · Jan 2004
  • Source
    Ioannis N Legakis · Costas Tzioras · Costas Phenekos

    Full-text · Article · Feb 2003 · Diabetes Care
  • C Phenekos
    [Show abstract] [Hide abstract]
    ABSTRACT: Numerous mainly cross-sectional studies have unequivocally shown an inverse relationship between birth weight of infants born at term and the incidence of impaired glucose tolerance, type 2 diabetes mellitus, insulin resistance, hypertension and coronary heart disease. These findings apply to both sexes and are not modified by confounding factors such as age or body mass index. Although the original studies in the UK involved a relatively small number of subjects whose records of birth weight were traced back more than 50 years earlier, similar findings were recorded from larger prospective studies in the USA and Northern Europe. Studies in twins did not support the theory that genetic factors predispose both to low birth weight and morbidity from impaired glucose tolerance, insulin resistance or coronary heart disease, and current evidence points to a resetting of major hormonal axes that control growth and metabolic processes as a possible cause of this association.
    No preview · Article · Feb 2001 · Journal of pediatric endocrinology & metabolism: JPEM
  • [Show abstract] [Hide abstract]
    ABSTRACT: Galanin, a neuropeptide, is found in the central nervous system and in a number of nonbrain areas including adrenal sympathetic medullar tissue and pancreas. Several studies involve galanin in the regulation of GH, which responds to stressful stimuli. This study refers to the investigation of the effect of a 20-min exercise on plasma human galanin (hGAL) and GH in middle-aged healthy volunteer adults. Thirteen individuals, 5 males and 8 females aged 40-50 years (44.7 +/- 2.95) were selected on the basis of normal body mass index (22.5 +/- 2.3 kg/m2) and the absence of endocrine or any other abnormality. Basal concentrations of GH and hGAL were measured between 0800 and 0900h after an overnight fast. Post exercise levels were recorded after termination of the stressful test and 15 min thereafter. GH and hGAL were determined by an immunoradiometric and radioimmunoassay, respectively. The exercise-potentiated GH response in all subjects with post-exercise levels significantly higher (11.09 +/- 1.8 ng/ml vs 1.27 +/- 0.7 ng/ml, p<0.0001, F=32.44) with the peak in the hormone level detected 15 min after the end of exercise (12.09 +/- 1.96 ng/ml). Plasma hGAL levels were also substantially affected by the acute exercise test, in that post exercise peripheral blood concentration was significantly higher from the basal values (21.51 +/- 9.94 vs 13.46 +/- 7.2 pg/ml, p<0.02, F=5.50). Again the hGAL values peaked 15 min after the end of exercise (24.0 +/- 10.5 pg/ml, P<0.015, F = 4.68). However, the time-correlation of the increments of GH and hGAL did not reach a statistically significant level (20 min: r=0.41, p=0.161., 35 min: r=-0.095, P=0.758). These results clearly show an independence of the two hormones. The responsivity of hGAL of middle-aged individuals to the exercise stimulus might be due to the higher releasable pool of the hormone.
    No preview · Article · Aug 2000 · Endocrine Research
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Immunoreactive CRH (IrCRH) is produced locally in experimentally induced and spontaneous inflammation. Where it exerts autocrine or paracrine proinflammatory effects. In addition, CRH is secreted by the human placenta, rat Leydig cells, and rat and human ovaries, where it may participate in the inflammatory processes of ovulation and luteolysis, and/or the regulation of steroidogenesis. Finally, CRH is secreted in vitro by cultured human epithelial and decidualized stromal endometrial cells. To investigate the presence of CRH in human endometrium in vivo, we examined this tissue immunohistochemically and by extraction/RIA using a polyclonal, highly specific antirat/human CRH antibody. Endometrial biopsies from 33 women, aged 23-43 yr (median age, 33.5 yr), were performed by linear endometrial curettage for diagnostic purposes at different stages of the cycle. Intense IrCRH staining was localized in the cytoplasm of cells of the endometrial glands in all samples examined. IrCRH was also found in endometrial stromal cells exhibiting decidual reaction and in local immune accessory cells. The mobility of the endometrial IrCRH molecule was similar to that of r/hCRH in reverse phase high pressure liquid chromatography. The presence of CRH in the endometrium, and more specifically in the glandular epithelium during the proliferative and secretory phases of the menstrual cycle together with its known proinflammatory properties, suggest that this neuropeptide might participate in the inflammatory-like phenomena of endometrial physiology, such as menstrual shedding, surface epithelium repair, and/or implantation of the blastocyst. The presence of CRH in decidualized stromal cells is in accordance with its previously reported production by in vitro decidualized cultured endometrial stromal cells as well as by the placental decidua.
    Full-text · Article · Apr 1996 · Journal of Clinical Endocrinology & Metabolism
  • [Show abstract] [Hide abstract]
    ABSTRACT: Recently, we demonstrated the presence of immunoreactive (Ir) CRH and its receptors in the rat ovary. To determine whether CRH is also present in human ovaries, we examined ovaries from normal women and patients with the polycystic ovarian syndrome (PCOS). Immunoreactive CRH in normal human ovaries had a similar distribution to that of rat ovarian IrCRH, as determined by immunohistochemistry. Thus, immunoreactivity was intense in the cytoplasm of thecal cells surrounding the ovarian follicles, in luteinized cells of the stroma, and in a subpopulation of cells within the corpora lutea. No IrCRH was present in oocytes of primordial follicles. Polycystic ovaries also had IrCRH in thecal cells; however, CRH immunostaining was less prominent or completely absent from the stroma or the sparsely present corpora lutea and was clearly detected in oocytes of primordial follicles. Using a specific RIA, the IrCRH content in extracts of normal ovaries was higher than that in polycystic ovaries (mean +/- SD, 0.075 +/- 0.02 vs. 0.038 +/- 0.009 pmol/g wet tissue, respectively; P < 0.05). Human follicular fluid samples collected from women undergoing ovarian hyperstimulation for assisted reproduction had low, but detectable, levels of IrCRH (mean +/- SD, 4.975 +/- 1.179 pmol/L), whereas IrCRH was undetectable in concurrently drawn plasma samples. IrCRH detected in normal and polycystic ovaries and in follicular fluid had similar chromatographic mobility to that of rat/human CRH-(1-41) by reverse phase HPLC. We conclude that IrCRH is present in normal human ovaries and follicular fluid, suggesting that this neuropeptide may play a regulatory role in one or more of the various functions of this gonad, such as ovulation and/or luteolysis, through its proinflammatory properties and/or its auto/paracrine regulation of steroid biosynthesis, in analogy to its action on testosterone secretion by the Leydig cell. Its decreased concentration and localization in primary oocytes of polycystic ovaries may be related to the increased androgen biosynthesis by the theca and stroma and/or to the oocyte dysfunction observed in women with the polycystic ovarian syndrome, respectively.
    No preview · Article · Nov 1994 · Journal of Clinical Endocrinology & Metabolism