Despoina Perrea

Propofol: A review of its non-anaesthetic effects

Propofol, a short-acting intravenous anaesthetic agent has gained wide acceptance since its introduction in the late 80s, not only in operating rooms but also in other departments, due to its several advantages. Apart from its multiple anaesthetic advantages, it has been reported recently that propofol exerts a number of non-anaesthetic effects. The drug stimulates constitutive nitric oxide (NO) production and inhibits inducible NO production. Propofol has also anxiolytic properties, which may be related to several neuromediator systems. Moreover, it has antioxidant, immunomodulatory, analgesic, antiemetic and neuroprotective effects. Furthermore, propofol inhibits both platelet aggregation and intracellular calcium increases in response to thrombin or ADP and it also exerts direct inhibitory effects on recombinant cardiac sarcolemmal KATP channels. All these beneficial properties may expand propofols clinical use.

Validation of the Finnish diabetes risk score (FINDRISC) questionnaire for screening for undiagnosed type 2 diabetes, dysglycaemia and the metabolic syndrome in Greece

AIM The present study aimed to validate the Finnish Type 2 Diabetes Risk Score (FINDRISC) questionnaire for its ability to predict the presence of any glucose homoeostasis abnormalities and the metabolic syndrome (MetS) in the Greek population. METHODS Validation was performed on a sample of individuals who had agreed to participate in a screening program for type 2 diabetes (T2D) prevention (the Greek part of the DE-PLAN study), using both FINDRISC and oral glucose tolerance tests (OGTT). Impaired fasting glucose (IFG) was defined as a fasting plasma glucose level of 6.1-6.9 mmol/L, and impaired glucose tolerance (IGT) as a 2-h plasma glucose of 7.8-11.0 mmol/L. The predictive value of the FINDRISC was cross-sectionally evaluated using the area under the receiver operating characteristic (AUROC) curve method. RESULTS A total of 869 individuals (379 men, aged 56.2 ± 10.8 years) were screened from the general population living in the city and suburbs of Athens. OGTT revealed the presence of unknown diabetes in 94 cases (10.8%), IFG in 85 (9.8%) and IGT in 109 (12.6%). The sensitivity of a FINDRISC score greater or equal to 15 (45% of the population) to predict unknown diabetes was 81.9% and its specificity was 59.7%. The AUROC curve for detecting unknown diabetes was 0.724 (95% CI: 0.677-0.770). For any dysglycaemia, the AUROC curve was 0.716 (0.680-0.752) while, for detection of the MetS, it was 0.733 (0.699-0.767). CONCLUSION The FINDRISC questionnaire performed well as a screening tool for the cross-sectional detection of unknown diabetes, IFG, IGT and the MetS in the Greek population.

Atherosclerosis regression study in rabbits upon olive pomace polar lipid extract administration

BACKGROUND AND AIMS Virgin olive oil polar lipid extract (OOPL) and olive pomace polar lipid extract (PPL) have similar antiatherosclerotic effects in cholesterol-fed rabbits. Our aim was to compare the effect of PPL with that of simvastatin on the progression of atherogenesis. METHODS AND RESULTS Rabbits were fed an atherogenic diet for 6 weeks in order to develop dyslipidemia and atheromatous lesions. Following documentation of these events in random animals (group A, n=6), the remaining were fed for 3 weeks with: standard chow alone (group B, n=6), chow supplemented with PPL (group C, n=6), and chow supplemented with simvastatin (group D, n=6). Blood was collected at 0, 6 and 9 weeks, to determine plasma lipid levels, plasma PAF-AH activity, platelet aggregation (PAF-EC(50)), resistance of plasma to oxidation (RPO) and extent of atheromatous lesions in aortas. The atherogenic diet induced dyslipidemia and increased PAF-AH activity. Dyslipidemia and PAF-activity reduced more effectively in groups C and D. RPO decreased in group B only. PAF-EC(50) values decreased in group C only. Atherogenesis progression in group C was prevented to an extent indistinguishable from that in group D. PAF-AH activity was positively correlated, whereas RPO was negatively correlated with the extent of atheromatous lesions. CONCLUSION PPL, as a dietary supplement, is equipotent to simvastatin in preventing the progression of atherogenesis.

Effect of pentoxifylline on vascular endothelial growth factor C and flk-1 expression on endometrial implants in the rat endometriosis model

OBJECTIVE To investigate the effects of pentoxifylline, on vascular endothelial growth factor (VEGF)-C and flk-1 expression in the rat endometriosis model. DESIGN Prospective, randomized, placebo-controlled study. SETTING Academic institution. ANIMAL(S) Twenty Wistar rats with surgically induced endometriosis. INTERVENTION(S) Animals were evaluated after surgical induction of endometriosis and random allocation to a group that received pentoxifylline and a control group that received NaCl 0.9%, for 3 weeks. At the end of the treatment period the animals were killed and the implants evaluated macroscopically as well as by immunohistochemistry. MAIN OUTCOME MEASURE(S) Morphologic changes of the endometriotic implants; and evaluation of VEGF-C and flk-1 expression by a semiquantitative analysis (HSCORE) for the intensity of immunohistochemical reactivity. RESULT(S) A significant reduction was observed in the mean volume of the endometriotic implants per animal in the treatment group as compared with the control group. There was a significant reduction not only in the mean volume of implants per animal but also in the mean number of implants per animal after treatment. By immunohistochemical evaluation (HSCORE), there was a significant reduction in VEGF-C expression after treatment in all areas examined. A significant reduction of flk-1 expression was also noted in the glandular compartment after treatment but not in the epithelial surface or stroma. CONCLUSION(S) Pentoxifylline may cause suppression of endometriotic lesions by suppressing angiogenesis through VEGF-C and flk-1 expression.

Evaluation of three methods for retrospective correction of vignetting on medical microscopy images utilizing two open source software tools.

Correction of vignetting on images obtained by a digital camera mounted on a microscope is essential before applying image analysis. The aim of this study is to evaluate three methods for retrospective correction of vignetting on medical microscopy images and compare them with a prospective correction method. One digital image from four different tissues was used and a vignetting effect was applied on each of these images. The resulted vignetted image was replicated four times and in each replica a different method for vignetting correction was applied with fiji and gimp software tools. The highest peak signal‐to‐noise ratio from the comparison of each method to the original image was obtained from the prospective method in all tissues. The morphological filtering method provided the highest peak signal‐to‐noise ratio value amongst the retrospective methods. The prospective method is suggested as the method of choice for correction of vignetting and if it is not applicable, then the morphological filtering may be suggested as the retrospective alternative method.

Dietary L-aspartate and L-glutamate inhibit fatty streak initiation in cholesterol-fed rabbit.

BACKGROUND AND AIM Low-density lipoprotein (LDL) oxidation is a potential atherogenic agent, and protecting LDL from oxidation prevents atherogenesis. It has been shown that L-aspartate and L-glutamate decrease lipid peroxidation after reoxygenation by means of the initiation of the cardiopulmonary bypass circuit (CPB), when supplemented to the CPB prime, and so they may protect against atherogenesis. The aim of this study was to evaluate the effect of the dietary administration of L-aspartate and L-glutamate on fatty streak onset in cholesterol-fed rabbit. METHODS AND RESULTS Male New Zealand white rabbits were fed for four weeks with either a high-cholesterol plus corn oil diet (control group) or the same diet supplemented with 12.5 mM L-aspartate and 12.5 mM L-glutamate in drinking water (Asp + Glu group). The mononuclear cells adhering to the endothelium and the intimal foam cells of the thoracic aorta were used to quantify the extent of atherosclerosis. Total serum cholesterol and lipid peroxidation activity, measured as thiobarbituric acid reactive substances (TBARS), were determined 0, 1 and 4 weeks after a 2-week adaptation period. There were no between-group differences in body weight or food intake during the intervention. Serum TBARS were significantly increased in both groups during the experimental period but without any statistical difference between groups. At the end of the dietary intervention, there was a ten-fold increase in total serum cholesterol concentration in both groups vs baseline. The numbers of adherent mononuclear cells and intimal foam cells were both significantly lower in the Asp + Glu group. CONCLUSIONS Our results suggest that dietary supplementation with L-aspartate and L-glutamate seems to protect the arterial wall from atherogenesis in an experimental animal.

Acute Hyperhomocysteinemia Impairs Endothelium Function in Subjects with Type 2 Diabetes Mellitus

The objective of the present study was to examine the effect of acute, methionine-induced hyperhomocysteinemia (HHCY) on endothelial function and indices of arterial stiffness in subjects with type 2 diabetes mellitus (T2DM). A total of 30 subjects with T2DM, free of macrovascular disease were examined in a crossover study. L-methionine (M) (0.1 g/kg) and water (W) load were given in random order with an interval of about 1 week in between. Endothelial function was assessed by flow-mediated vasodilation (FMD). Arterial stiffness was assessed by determination of augmentation index (AI). Measurements were performed in the fasting state, 1, 2 and 3 h after the M or the W load. Total plasma homocysteine (HCY) levels did not change after W administration, while M administration resulted in a significant increase in HCY concentrations at 3 h. FMD throughout the experiment expressed as area under the curve (AUC) was significantly lower after the M than after the W load. Consistent with impairment in endothelial function, the AUC of AI was significantly higher after the M than after the W administration. Acute HHCY impairs endothelial function and increases arterial stiffness in patients with T2DM. This effect is probably mediated by a reduction of nitric oxide bioavailability in endothelium.

Metabolic syndrome and Mediterranean dietary pattern in a sample of young, male, Greek navy recruits

Figure 1 Distribution of the Mediterranean diet score among the participants. The Mediterranean Diet (MD) is very beneficial, because of cardiovascular and other effects. The dietary habits of the population nowadays, however, have considerably changed. As there are only few data about the frequency of the metabolic syndrome (MS) in young Greeks, and their adherence to the MD, we studied the prevalence of the MS in a representative sample of young Navy recruits, while investigating adherence to the MD. We studied demographic, lifestyle, dietary and clinical information in 832 male navy recruits (M SD, 22.5 2.8 years-old [range 17e39, full data available for 714]). The MS was defined according to the IDF and NCEP criteria. Dietary habits were recorded through a validated, quantitative food-frequency questionnaire that assessed the consumption of various foods over the previous year, including individual portion sizes. A special diet score (range 0e55) was developed that assessed adherence to the MD (Table 1). The subjects ‘‘closer’’ to it were identified with the median value of the monthly average of foods consumed [1]. All gave their informed consents and the study was approved by the participating institution’s ethics committee. The MS was present in 11.1% and 5.0% (IDF and NCEP criteria, respectively). Around 32% were overweight (BMI: 25e30 kg/m) and 8% obese (BMI 30 kg/m). Smoking was very prevalent (50.4%). Adherence to the MD was quite poor: out of a maximum possible score of 55, the majority (w99%) had a score <31 (M SD, 24.5 3.68, median 25.0) (Fig. 1). In a multivariate logistic regression model, with the MS as dependent variable and the MD score as an independent one, and after adjustment for age, smoking habits, exercise activity, marital status, coffee consumption, family history of diabetes and CHD and several biochemical measurements, MD did not predict the presence of the MS, with either criteria used. It seems that adherence to the MD depends on age, possibly because in younger people the traditional MD style is decreasing. This is probably due to the globalization of food practices and habits among the young, with the advent and prevalence of westernised, fast-food diets in these age

Asphyxial cardiac arrest, resuscitation and neurological outcome in a Landrace/Large-White swine model

The vast majority of laboratory studies on animals have focused on ventricular fibrillation (VF) and not on cardiac arrest (CA) resulting from asphyxia. The aim of this study was to develop a clinically relevant animal model in Landrace/Large-White swine of asphyxial CA resuscitated using the European Resuscitation Council guidelines. Survival and 24 h neurological outcome in terms of functional deficit were also evaluated. Asphyxial arrest was induced by clamping the endotracheal tube (ETT) in 10 Landrace/Large-White piglets. After 4 min of untreated arrest, resuscitation was initiated by unclamping the ETT, 100% oxygen mechanical ventilation, 2 min chest compressions and epinephrine administration. Advanced Life Support algorithm was followed. In case of restoration of spontaneous circulation, the animals were supported for one hour and then observed for 23 h. Coronary perfusion pressure was significantly higher in surviving animals (P < 0.001) during cardiopulmonary resuscitation. End-tidal CO2 was significantly higher in the animals that survived than in non-surviving animals (P = 0.001). All of the animals were severely neurologically impaired 24 h after CA. This refined model of asphyxia CA is easily reproducible and may be used for pharmacological studies in CA.

The use of mice and rats as animal models for cardiopulmonary resuscitation research

Cardiopulmonary resuscitation (CPR) after the induction of cardiac arrest (CA) has been studied in mice and rats. The anatomical and physiological parameters of the cardiopulmonary system of these two species have been defined during experimental studies and are comparable with those of humans. Moreover, these animal models are more ethical to establish and are easier to manipulate, when compared with larger experimental animals. Accordingly, the effects of successful CPR on the function of vital organs, such as the brain, have been investigated because damage to these vital organs is of concern in CA survivors. Furthermore, the efficacy of several drugs, such as adrenaline (epinephrine), vasopressin and nitroglycerin, has been evaluated for use in CA in these small animal models. The purpose of these studies is not only to increase the rate of survival of CA victims, but also to improve their quality of life by reducing damage to their vital organs after CA and during CPR.