31 results on '"Papadea P"'
Search Results
2. Inhibition of mammalian mtDNA transcription acts paradoxically to reverse diet-induced hepatosteatosis and obesity
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Jiang, Shan, Yuan, Taolin, Rosenberger, Florian A., Mourier, Arnaud, Dragano, Nathalia R. V., Kremer, Laura S., Rubalcava-Gracia, Diana, Hansen, Fynn M., Borg, Melissa, Mennuni, Mara, Filograna, Roberta, Alsina, David, Misic, Jelena, Koolmeister, Camilla, Papadea, Polyxeni, de Angelis, Martin Hrabe, Ren, Lipeng, Andersson, Olov, Unger, Anke, Bergbrede, Tim, Di Lucrezia, Raffaella, Wibom, Rolf, Zierath, Juleen R., Krook, Anna, Giavalisco, Patrick, Mann, Matthias, and Larsson, Nils-Göran
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- 2024
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3. New Clinical Markers of Oxidized Lipid-Associated Protein Damage in Children and Adolescents with Obesity
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Eirini Kostopoulou, Athina Varemmenou, Electra Kalaitzopoulou, Polyxeni Papadea, Marianna Skipitari, Andrea Paola Rojas Gil, Bessie E. Spiliotis, Sotirios Fouzas, and Christos D. Georgiou
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PrMDA ,PrTBARS ,LOOH ,oxidative stress ,obesity ,children ,Pediatrics ,RJ1-570 - Abstract
Obesity in children and adolescents has been associated with oxidative stress (OS). The lipid hydroperoxides (LOOH) and the malondialdehyde (MDA) and thiobarbituric reactive substances (TBARS) that oxidatively modify proteins (Pr) (i.e., PrMDA and PrTBARS, respectively) represent markers of OS-associated lipid peroxidation. We aimed to assess OS in children and adolescents with obesity using—for the first time—markers involved in the early and late lipid oxidation process. LOOH, PrMDA, and PrTBARS were investigated in 41 children and adolescents with obesity and 31 controls. Obesity was defined as BMI > 95% for age and sex. The PrMDA/PrTBARS pair, which reflects a late peroxidation stage, was found to be significantly high (39%/180%) in children and adolescents with obesity compared to controls (p < 0.001). Similarly, the early LOOH peroxidation stage marker was increased by 30%. The studied OS parameters were not influenced by sex or age. Our study introduces LOOH, PrTBARS, and PrMDA as markers for evaluating OS in children and adolescents with obesity. LOOH, PrTBARS, and PrMDA may also hold promise as prognostic markers for potential obesity-associated long-term complications.
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- 2024
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4. Time progression and regional expression of brain oxidative stress induced by obstructive jaundice in rats
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Konstantinos Lilimpakis, Aidona Tsepelaki, Electra Kalaitzopoulou, Dimitrios Zisimopoulos, Polyxeni Papadea, Marianna Skipitari, Athina Varemmenou, Apostolos Aggelis, Constantine Vagianos, Constantine Constantoyannis, and Christos D. Georgiou
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Oxidative stress ,Obstructive jaundice ,Protein oxidation ,Protein carbonyls ,Rhodamine B hydrazide ,Lipid peroxidation ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Obstructive jaundice induces oxidative changes in the brain parenchyma and plays significant role in clinical manifestations of hepatic encephalopathy. We aim to study the progression of the brain oxidative status over time and the differences of its pattern over the hemispheres, the brainstem and the cerebellum. We use an experimental model in rats and measuring the oxidative stress (OS) specific biomarkers protein malondialdehyde (PrMDA) and protein carbonyls (PrC = O). Results Hyperbilirubinemia has been confirmed in all study groups as the result of common bile duct obstruction. We confirmed increase in both PrMDA and PrC = O biomarkers levels with different type of changes over time. We also confirmed that the oxidative process develops differently in each of the brain areas in study. Conclusions The present study confirms the progressive increase in OS in all brain areas studied using markers indicative of cumulative protein modification.
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- 2022
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5. Physical Differences between Man-Made and Cosmic Microwave Electromagnetic Radiation and Their Exposure Limits, and Radiofrequencies as Generators of Biotoxic Free Radicals
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Christos D. Georgiou, Electra Kalaitzopoulou, Marianna Skipitari, Polyxeni Papadea, Athina Varemmenou, Vassilios Gavriil, Evangelia Sarantopoulou, Zoe Kollia, and Alkiviadis-Constantinos Cefalas
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natural/man-made EMF ,ELF/RF EMR ,natural vs. man-made exposure limits ,EMR biological effects ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
The critical arguments for radiofrequency radiation exposure limits are currently based on the principle that radio frequencies (RF) and electromagnetic fields (EMFs) are non-ionising, and their exposure limits are even 100-fold lower than those emitted from the Sun in the whole RF-EMF spectrum. Nonetheless, this argument has been challenged by numerous experimental and theoretical studies on the diverse biological effects of RF-EMF at much lower power density (W/m2) levels than today’s exposing limits. On the other hand, less attention has been given to counterarguments based on the differences in the physics concepts underlying man-made versus natural electromagnetic radiation (EMR) and on the fact that man’s biology has been adapted to the natural EMR levels reaching Earth’s surface at single EMF wavelengths, which are the natural limits of man’s exposure to EMFs. The article highlights the main points of interaction of natural and man-made radiation with biomatter and reveals the physical theoretical background that explains the effects of man-made microwave radiation on biological matter. Moreover, the article extends its analysis on experimental quantum effects, establishing the “ionising-like” effects of man-made microwave radiation on biological matter.
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- 2022
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6. Novel oxidized LDL-based clinical markers in peritoneal dialysis patients for atherosclerosis risk assessment
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Polyxeni Papadea, Electra Kalaitzopoulou, Marianna Skipitari, Athina Varemmenou, Marios Papasotiriou, Evangelos Papachristou, Dimitrios Goumenos, Tilman Grune, and Christos D. Georgiou
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Atherosclerosis ,Peritoneal dialysis ,Oxidized LDL ,Oxidative stress ,Clinical markers ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Maintenance peritoneal dialysis (PD) is commonly associated with cardiovascular diseases (CVDs), whose risk is assessed via LDL-C. Nonetheless, oxidized LDL (oxLDL), as being a key component of atherosclerotic lesions, could be also associated with atherosclerosis and related CVDs. However, its predictive value for CVDs risk assessment is subject of research studies due to the lack of specific methods to measure oxLDL status from its individual lipid/protein components. In the present study, six novel oxLDL markers, representative of certain oxidative modifications on the LDL protein and lipid components, are measured in atherosclerosis-prone PD patients (39) versus those in chronic kidney disease patients (61) under hemodialysis (HD) and healthy controls (40). LDL from serum of PD, HD and control subjects were isolated and fractionated into cholesteryl esters, triglycerides, free cholesterol, phospholipids and apolipoprotein B100 (apoB100). Subsequently the oxLDL markers cholesteryl ester hydroperoxides (-OOH), triglyceride-OOH, free cholesterol-OOH, phospholipid-OOH, apoB100 malondialdehyde and apoB100 dityrosines were measured. LDL carotenoid levels and LDL particle serum concentration were also measured. The levels of all oxLDL lipid-OOH markers were significantly elevated in PD patients versus control, while the levels of cholesteryl ester-/triglyceride-/free cholesterol-OOH were significantly elevated in PD versus HD patients, regardless of patients’ underlying medical conditions, sex, age, PD type, clinical biochemical markers and medication. It should be noted that all fractionated lipid-OOH levels were inversely correlated with LDL-P concentration, while LDL-P concentration was not correlated with LDL-C in PD patients. Moreover, LDL carotenoids were significantly lower in PD patients versus control. The increased levels of oxLDL status specific markers in both PD and HD patients (compared to control), support a potential prognostic value of oxLDL regarding CVD risk assessment in both patient groups. Lastly, the study introduces the oxLDL peroxidation markers free cholesterol-OOH and cholesteryl ester-OOH as complementary to LDL-P number, and as possible alternatives to LDL-C.
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- 2023
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7. Time progression and regional expression of brain oxidative stress induced by obstructive jaundice in rats
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Lilimpakis, Konstantinos, Tsepelaki, Aidona, Kalaitzopoulou, Electra, Zisimopoulos, Dimitrios, Papadea, Polyxeni, Skipitari, Marianna, Varemmenou, Athina, Aggelis, Apostolos, Vagianos, Constantine, Constantoyannis, Constantine, and Georgiou, Christos D.
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- 2022
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8. Methods on LDL particle isolation, characterization, and component fractionation for the development of novel specific oxidized LDL status markers for atherosclerotic disease risk assessment
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Polyxeni Papadea, Marianna Skipitari, Electra Kalaitzopoulou, Athina Varemmenou, Maria Spiliopoulou, Marios Papasotiriou, Evangelos Papachristou, Dimitrios Goumenos, Anny Onoufriou, Eleftheria Rosmaraki, Irene Margiolaki, and Christos D. Georgiou
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oxidized LDL ,apoB100 ,LDL lipid fractions ,LDL-C ,HDL-C ,clinical markers ,Medicine (General) ,R5-920 - Abstract
The present study uses simple, innovative methods to isolate, characterize and fractionate LDL in its main components for the study of specific oxidations on them that characterize oxidized low-density lipoprotein (oxLDL) status, as it causatively relates to atherosclerosis-associated cardiovascular disease (CVD) risk assessment. These methods are: (a) A simple, relatively time-short, low cost protocol for LDL isolation, to avoid shortcomings of the currently employed ultracentrifugation and affinity chromatography methodologies. (b) LDL purity verification by apoB100 SDS-PAGE analysis and by LDL particle size determination; the latter and its serum concentration are determined in the present study by a simple method more clinically feasible as marker of CVD risk assessment than nuclear magnetic resonance. (c) A protocol for LDL fractionation, for the first time, into its main protein/lipid components (apoB100, phospholipids, triglycerides, free cholesterol, and cholesteryl esters), as well as into LDL carotenoid/tocopherol content. (d) Protocols for the measurement, for the first time, of indicative specific LDL component oxidative modifications (cholesteryl ester-OOH, triglyceride-OOH, free cholesterol-OOH, phospholipid-OOH, apoB100-MDA, and apoB100-DiTyr) out of the many (known/unknown/under development) that collectively define oxLDL status, which contrasts with the current non-specific oxLDL status evaluation methods. The indicative oxLDL status markers, selected in the present study on the basis of expressing early oxidative stress-induced oxidative effects on LDL, are studied for the first time on patients with end stage kidney disease on maintenance hemodialysis, selected as an indicative model for atherosclerosis associated diseases. Isolating LDL and fractionating its protein and main lipid components, as well as its antioxidant arsenal comprised of carotenoids and tocopherols, paves the way for future studies to investigate all possible oxidative modifications responsible for turning LDL to oxLDL in association to their possible escaping from LDL’s internal antioxidant defense. This can lead to studies to identify those oxidative modifications of oxLDL (after their artificial generation on LDL), which are recognized by macrophages and convert them to foam cells, known to be responsible for the formation of atherosclerotic plaques that lead to the various CVDs.
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- 2023
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9. Exploring a Possible Interplay between Schizophrenia, Oxytocin, and Estrogens: A Narrative Review
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Danae Papadea, Christina Dalla, and Despina A. Tata
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estrogen hypothesis ,oxytocin ,psychosis ,schizophrenia ,sex hormones ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Schizophrenia is characterized by symptoms of psychosis and sociocognitive deficits. Considering oxytocin’s antipsychotic and prosocial properties, numerous clinical, and preclinical studies have explored the neuropeptide’s therapeutic efficacy. Sex differences in the clinical course of schizophrenia, as well as in oxytocin-mediated behaviors, indicate the involvement of gonadal steroid hormones. The current narrative review aimed to explore empirical evidence on the interplay between schizophrenia psychopathology and oxytocin’s therapeutic potential in consideration of female gonadal steroid interactions, with a focus on estrogens. The review was conducted using the PubMed and PsychINFO databases and conforms to the Scale for the Assessment of Narrative Review Articles (SANRA) guidelines. The results suggest a potential synergistic effect of the combined antipsychotic effect of oxytocin and neuroprotective effect of estrogen on schizophrenia. Consideration of typical menstrual cycle-related hormonal changes is warranted and further research is needed to confirm this assumption.
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- 2023
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10. Water Modification by Cold Plasma Jet with Respect to Physical and Chemical Properties
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Panagiotis Svarnas, Michael Poupouzas, Konstantia Papalexopoulou, Electra Kalaitzopoulou, Marianna Skipitari, Polyxeni Papadea, Athina Varemmenou, Evangelos Giannakopoulos, Christos D. Georgiou, Stavroula Georga, and Christoforos Krontiras
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plasma jet ,DBD ,argon ,UV-NIR optical emission spectroscopy ,water ,phosphate-buffered saline ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This work is devoted to unbuffered and buffered water treatment by means of atmospheric pressure cold plasma of electrical discharges. The interest in the activation of these two liquids by plasma-induced, gaseous-phase chemistry ranges over a wide area of potential applications and interdisciplinary scientific fields. These include biology, medicine, sanitation, environmental restoration, agriculture, etc. Atmospheric pressure cold plasma is here produced in the form of a plasma jet and set into physical contact with the liquid specimens. The operational window of the treatment, in terms of plasma reactivity, is determined by means of UV-NIR optical emission spectroscopy, and the treated liquids are probed in a variety of respects. Evaporation rate, temperature, acidity and basicity, resistivity, and oxidation-reduction potential are measured as a function of the treatment time, either in-situ or ex-situ. The formation of principal reactive oxygen species, i.e., •OH, H2O2 and O2•−, with a plasma jet mean power lower than 400 mW, is eventually demonstrated and their concentration is measured with original methods borrowed from the biology field. The experimental results are linked to reports published over the last ten years, which are compiled in a brief but meaningful review.
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- 2022
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11. Maternal Calorie Restriction Induces a Transcriptional Cytoprotective Response in Embryonic Liver Partially Dependent on Nrf2
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George I. Habeos, Fotini Filippopoulou, Evagelia E. Habeos, Electra Kalaitzopoulou, Marianna Skipitari, Polyxeni Papadea, George Lagoumintzis, Athanasios Niarchos, Christos D. Georgiou, and Dionysios V. Chartoumpekis
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Keap1 ,Nfe2l2 ,reactive oxygen species ,oxidative stress ,gluconeogenesis ,lipogenesis ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background: Calorie restriction is known to enhance Nrf2 signaling and longevity in adult mice, partially by reducing reactive oxygen species, but calorie restriction during pregnancy leads to intrauterine growth retardation. The latter is associated with fetal reprogramming leading to increased incidence of obesity, metabolic syndrome and diabetes in adult life. Transcription factor Nrf2 is a central regulator of the antioxidant response and its crosstalk with metabolic pathways is emerging. We hypothesized that the Nrf2 pathway is induced in embryos during calorie restriction in pregnant mothers. Methods: From gestational day 10 up to day 16, 50% of the necessary mouse diet was provided to Nrf2 heterozygous pregnant females with fathers being of the same genotype. Embryos were harvested at the end of gestational day 16 and fetal liver was used for qRT-PCR and assessment of oxidative stress (OS). Results: Intrauterine calorie restriction led to upregulation of mRNA expression of antioxidant genes (Nqo1, Gsta1, Gsta4) and of genes related to integrated stress response (Chac1, Ddit3) in WT embryos. The expression of a key gluconeogenic (G6pase) and two lipogenic genes (Acacb, Fasn) was repressed in calorie-restricted embryos. In Nrf2 knockout embryos, the induction of Nqo1 and Gsta1 genes was abrogated while that of Gsta4 was preserved, indicating an at least partially Nrf2-dependent induction of antioxidant genes after in utero calorie restriction. Measures of OS showed no difference (superoxide radical and malondialdehyde) or a small decrease (thiobarbituric reactive substances) in calorie-restricted WT embryos. Conclusions: Calorie restriction during pregnancy elicits the transcriptional induction of cytoprotective/antioxidant genes in the fetal liver, which is at least partially Nrf2-dependent, with a physiological significance that warrants further investigation.
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- 2022
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12. Immunosuppressive regimens based on Cyclophospamide or Calcineurin inhibitors: Comparison of their effect in the long term outcome of Primary Membranous Nephropathy.
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Maria Stangou, Smaragdi Marinaki, Evangelos Papachristou, Kyriaki Kolovou, Erasmia Sambani, Synodi Zerbala, Panagiota Papadea, Olga Balafa, Karolos-Pavlos Rapsomanikis, Aimilios Andrikos, Panagiota Manolakaki, Dorothea Papadopoulou, Efstathios Mitsopoulos, Helen Liakou, Paraskevi-Evi Andronikidi, Vasiliki Choulitoudi, George Moustakas, Dimitra Galitsiou, Eugene Dafnis, Kostas Stylianou, Ioannis Stefanidis, Spyridon Golfinopoulos, Stylianos Panagoutsos, Maria Tsilivigkou, Apostolos Papadogianakis, Ioannis Tzanakis, Athanasios Sioulis, Dimitrios Vlachakos, Eirini Grapsa, Sophia Spaia, Nikolaos Kaperonis, Christos Paliouras, Christos Dioudis, Fani Papoulidou, Theofanis Apostolou, Christos Iatrou, Ioannis Boletis, Dimitrios Goumenos, and Aikaperini Papagianni
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Medicine ,Science - Abstract
IntroductionManagement of the Primary Membranous Nephropathy (PMN) usually involves administration of immunosuppressives. Cyclophosphamide (Cyclo) and Calcineurin Inhibitors (CNIs) are both widely used but only limited data exist to compare their efficacy in long term follow-up.AimThe aim of the present study was to estimate and compare long term effects of Cyclo and CNIs in patients with PMN.Patients-methodsClinical data, histologic findings and long term outcome were retrospectively studied. The response to treatment and rate of relapse was compared between patients treated with CNIs or Cyclo based immunosuppressive regimens.ResultsTwenty three centers participated in the study, with 752 PMN patients (Mean age 53.4(14-87) yrs, M/F 467/285), followed for 10.1±5.7 years. All patients were initially treated with Renin Angiotensin Aldosterone System inhibitors (RAASi) for at least 6 months. Based on their response and tolerance to initial treatment, patients were divided into 3 groups, group I with spontaneous remission, who had no further treatment, group II, continued on RAASi only, and group III on RAASi+immunosuppression. Immunosuppressive regimes were mainly based on CNIs or Cyclo. Frequent relapses and failure to treatment were more common between patients who had started on CNIs (n = 381) compared to those initially treated with Cyclo (n = 110), relapse rate: 25.2% vs. 6.4%, pConclusionsLong term follow up showed that administration of Cyclo in PMN is followed by better preservation of renal function, increased response rate and less frequent relapses, compared to CNIs.
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- 2019
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13. The Oxygen Release Instrument: Space Mission Reactive Oxygen Species Measurements for Habitability Characterization, Biosignature Preservation Potential Assessment, and Evaluation of Human Health Hazards
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Christos D. Georgiou, Christopher P. McKay, Richard C. Quinn, Electra Kalaitzopoulou, Polyxeni Papadea, and Marianna Skipitari
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planetary oxygen-based reactive oxidants ,instrument ,habitability ,biosignatures ,Science - Abstract
We describe the design of an instrument, the OxR (for Oxygen Release), for the enzymatically specific and non-enzymatic detection and quantification of the reactive oxidant species (ROS), superoxide radicals (O2•−), and peroxides (O22−, e.g., H2O2) on the surface of Mars and Moon. The OxR instrument is designed to characterize planetary habitability, evaluate human health hazards, and identify sites with high biosignature preservation potential. The instrument can also be used for missions to the icy satellites of Saturn’s Titan and Enceladus, and Jupiter’s Europa. The principle of the OxR instrument is based on the conversion of (i) O2•− to O2 via its enzymatic dismutation (which also releases H2O2), and of (ii) H2O2 (free or released by the hydrolysis of peroxides and by the dismutation of O2•−) to O2 via enzymatic decomposition. At stages i and ii, released O2 is quantitatively detected by an O2 sensor and stoichiometrically converted to moles of O2•− and H2O2. A non-enzymatic alternative approach is also designed. These methods serve as the design basis for the construction of a new small-footprint instrument for specific oxidant detection. The minimum detection limit of the OxR instrument for O2•− and O22− in Mars, Lunar, and Titan regolith, and in Europa and Enceladus ice is projected to be 10 ppb. The methodology of the OxR instrument can be rapidly advanced to flight readiness by leveraging the Phoenix Wet Chemical Laboratory, or microfluidic sample processing technologies.
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- 2019
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14. Growth Hormone Secretion and Bone Mineral Density in Prepubertal Black and White Boys
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Wright, N.M., Papadea, N., Veldhuis, J.D., and Bell, N.H.
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- 2002
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15. Immunosuppressive regimens based on Cyclophospamide or Calcineurin inhibitors: Comparison of their effect in the long term outcome of Primary Membranous Nephropathy
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Stangou, M. Marinaki, S. Papachristou, E. Kolovou, K. Sambani, E. Zerbala, S. Papadea, P. Balafa, O. Rapsomanikis, K.-P. Andrikos, A. Manolakaki, P. Papadopoulou, D. Mitsopoulos, E. Liakou, H. Andronikidi, P.-E. Choulitoudi, V. Moustakas, G. Galitsiou, D. Dafnis, E. Stylianou, K. Stefanidis, I. Golfinopoulos, S. Panagoutsos, S. Tsilivigkou, M. Papadogianakis, A. Tzanakis, I. Sioulis, A. Vlachakos, D. Grapsa, E. Spaia, S. Kaperonis, N. Paliouras, C. Dioudis, C. Papoulidou, F. Apostolou, T. Iatrou, C. Boletis, I. Goumenos, D. Papagianni, A.
- Abstract
Introduction Management of the Primary Membranous Nephropathy (PMN) usually involves administration of immunosuppressives. Cyclophosphamide (Cyclo) and Calcineurin Inhibitors (CNIs) are both widely used but only limited data exist to compare their efficacy in long term followup. Aim The aim of the present study was to estimate and compare long term effects of Cyclo and CNIs in patients with PMN. Patients-methods Clinical data, histologic findings and long term outcome were retrospectively studied. The response to treatment and rate of relapse was compared between patients treated with CNIs or Cyclo based immunosuppressive regimens. Results Twenty three centers participated in the study, with 752 PMN patients (Mean age 53.4(14- 87) yrs, M/F 467/285), followed for 10.1±5.7 years. All patients were initially treated with Renin Angiotensin Aldosterone System inhibitors (RAASi) for at least 6 months. Based on their response and tolerance to initial treatment, patients were divided into 3 groups, group I with spontaneous remission, who had no further treatment, group II, continued on RAASi only, and group III on RAASi+immunosuppression. Immunosuppressive regimes were mainly based on CNIs or Cyclo. Frequent relapses and failure to treatment were more common between patients who had started on CNIs (n = 381) compared to those initially treated with Cyclo (n = 110), relapse rate: 25.2% vs. 6.4%, p
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- 2019
16. Histological grading in primary membranous nephropathy is essential for clinical management and predicts outcome of patients
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Stangou, M.J. Marinaki, S. Papachristou, E. Liapis, G. Pateinakis, P. Gakiopoulou, H. Nikolaidou, C. Kolovou, K. Lampropoulou, I.-T. Zerbala, S. Papadea, P. Dounousi, E. Balafa, O. Pavlakou, P. Andrikos, A. Balassi, E. Manolakaki, P. Moustakas, G. Galitsiou, D. Mitsopoulos, E. Vourlakou, C. Choulitoudi, V. Andronikidi, P.-E. Stefanidis, I. Golfinopoulos, S. Dafnis, E. Stylianou, K. Panagoutsos, S. Papadogianakis, A. Tzanakis, I. Sioulis, A. Vlahakos, D. Grapsa, I. Tsilivigkou, M. Kaperonis, N. Paliouras, C. Dioudis, C. Spaia, S. Apostolou, T. Iatrou, C. Boletis, J. Goumenos, D. Papagianni, A.
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Aims: Diagnosis of primary membranous nephropathy (PMN) is mainly based on immunofluorescence/immunohistochemistry findings. However, assessment of specific features on optical microscopy can help to estimate the severity of the disease, guide treatment and predict the response. The aim of this study was to identify, classify and grade the precise histological findings in PMN to predict renal function outcome and guide treatment. Methods and results: Histological parameters, including focal segmental sclerosis (FSGS), tubular atrophy (TA), interstitial fibrosis (IF) and vascular hyalinosis (VH), were re-evaluated in 752 patients with PMN. Their predictive value was estimated separately, and also in a combination score (FSTIV) graded from 0 to 4. Finally, the impact of histology was assessed in the response to immunosuppressive treatment. Mean age of patients was 53.3 (15–85) years and most presented with nephrotic syndrome. FSGS was present in 32% and VH in 51% of the patients, while TA and IF were graded as stage ≥1 in 52% and 51.4%, respectively. The follow-up period was 122.3 (112–376) months. FSGS, TA and IF and VH were associated with impaired renal function at diagnosis (P = 0.02, P 50% eGFR reduction, FSGS (P = 0.001) and TA (P = 0.02). Also, patients presented with FSGS, IF, VH and/or with FSTIV > 1 could benefit from immunosuppression, regardless of clinical presentation. Conclusions: The presence and degree of four histological indices, FSGS, VH, TA and IF, assessed separately or in combination, and FSTIV score not only predict renal function outcome after long-term follow-up, but can also help in the choice of appropriate treatment. Decisions concerning immunosuppressive treatment can be guided by pathology regardless of clinical findings. © 2019 The Authors. Histopathology published by John Wiley & Sons Ltd
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- 2019
17. Increased Serum 1,25-Dihydroxyvitamin D after Growth Hormone Administration is not Parathyroid Hormone-Mediated
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Wright, N. M., Papadea, N., Wentz, B., Hollis, B., Willi, S., and Bell, N. H.
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- 1997
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18. Human Immunoglobulin G and Immunoglobulin G Subclasses: Biochemical, Genetic, and Clinical Aspects
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Papadea, Christine and Check, Irene
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Human IgG consists of two identical heavy (H) chains and two identical light (L) chains joined by interchain disulfide bridges. Heterogeneity in the amino acid sequences of the H and L polypeptides results in at least three types of IgG variants at the structural and genetic levels. The four isotypic forms are IgG1, IgG2, IgG3, and IgG4, which share extensive homologies in the primary structure of their H chains. As a result, the subclasses cross-react antigenically, but they can be differentiated on the basis of subtle architectural dissimilarities. The biological and effector properties of the IgG isotypes have been associated, in part, with their structural differences. Genes determining the synthesis of human IgG heavy chains are located on chromosome 14. In several clinical situations the isotypes appear to be regulated or expressed in patterns reflecting the gene arrangement. The numeric designations of the subclasses correspond to the order of their proportional amounts in healthy adult serum: IgGl> IgG2 > IgG3 > IgG4.Awareness of the importance of the roles of the four IgG isotypes in human health has steadily increased since they were first described in the 1960s. The recognition that deficits or increases in selected IgG subclasses may have clinical consequences has prompted considerable interest in quantifying the four isotypes in clinical specimens. In particular, deficiencies of IgG2, IgG3, and IgG4, singly or combined, are associated with chronic infections which may not be readily recognized in otherwise healthy people with normal serum total IgG concentrations. Different assay methods using polyclonal or monoclonal antisera with various calibrants have been applied; however, no standardized method exists at the present. IgG deficits are associated with gene defects and are acquired in secondary immunodeficiencies in conjunction with other disorders. IgG isotype selectivity has been recognized in autoimmune diseases and in response to carbohydrate and protein antigens derived from pathogenic microorganisms and ommon allergens.
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- 1989
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19. Increased Whole Blood Viscosity during Coronary Artery Bypass Surgery
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Hunter, Robert L, Papadea, Christine, Gallagher, Christopher J, Finlayson, Donald C, and Check, Irene J
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- 1990
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20. Quality control of immunoglobulin G (IgG) subclass assays in the clinical laboratory
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Papadea, C
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- 1988
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21. Author Correction: Older age reduces mtDNA mutation inheritance.
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Papadea P and Larsson NG
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- 2024
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22. New Clinical Markers of Oxidized Lipid-Associated Protein Damage in Children and Adolescents with Obesity.
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Kostopoulou E, Varemmenou A, Kalaitzopoulou E, Papadea P, Skipitari M, Rojas Gil AP, Spiliotis BE, Fouzas S, and Georgiou CD
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Obesity in children and adolescents has been associated with oxidative stress (OS). The lipid hydroperoxides (LOOH) and the malondialdehyde (MDA) and thiobarbituric reactive substances (TBARS) that oxidatively modify proteins (Pr) (i.e., PrMDA and PrTBARS, respectively) represent markers of OS-associated lipid peroxidation. We aimed to assess OS in children and adolescents with obesity using-for the first time-markers involved in the early and late lipid oxidation process. LOOH, PrMDA, and PrTBARS were investigated in 41 children and adolescents with obesity and 31 controls. Obesity was defined as BMI > 95% for age and sex. The PrMDA/PrTBARS pair, which reflects a late peroxidation stage, was found to be significantly high (39%/180%) in children and adolescents with obesity compared to controls ( p < 0.001). Similarly, the early LOOH peroxidation stage marker was increased by 30%. The studied OS parameters were not influenced by sex or age. Our study introduces LOOH, PrTBARS, and PrMDA as markers for evaluating OS in children and adolescents with obesity. LOOH, PrTBARS, and PrMDA may also hold promise as prognostic markers for potential obesity-associated long-term complications.
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- 2024
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23. Novel oxidized LDL-based clinical markers in peritoneal dialysis patients for atherosclerosis risk assessment.
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Papadea P, Kalaitzopoulou E, Skipitari M, Varemmenou A, Papasotiriou M, Papachristou E, Goumenos D, Grune T, and Georgiou CD
- Subjects
- Humans, Cholesterol Esters, Cholesterol, LDL, Lipoproteins, LDL metabolism, Biomarkers, Cholesterol, Risk Assessment, Phospholipids, Triglycerides, Peritoneal Dialysis adverse effects, Atherosclerosis etiology
- Abstract
Maintenance peritoneal dialysis (PD) is commonly associated with cardiovascular diseases (CVDs), whose risk is assessed via LDL-C. Nonetheless, oxidized LDL (oxLDL), as being a key component of atherosclerotic lesions, could be also associated with atherosclerosis and related CVDs. However, its predictive value for CVDs risk assessment is subject of research studies due to the lack of specific methods to measure oxLDL status from its individual lipid/protein components. In the present study, six novel oxLDL markers, representative of certain oxidative modifications on the LDL protein and lipid components, are measured in atherosclerosis-prone PD patients (39) versus those in chronic kidney disease patients (61) under hemodialysis (HD) and healthy controls (40). LDL from serum of PD, HD and control subjects were isolated and fractionated into cholesteryl esters, triglycerides, free cholesterol, phospholipids and apolipoprotein B100 (apoB100). Subsequently the oxLDL markers cholesteryl ester hydroperoxides (-OOH), triglyceride-OOH, free cholesterol-OOH, phospholipid-OOH, apoB100 malondialdehyde and apoB100 dityrosines were measured. LDL carotenoid levels and LDL particle serum concentration were also measured. The levels of all oxLDL lipid-OOH markers were significantly elevated in PD patients versus control, while the levels of cholesteryl ester-/triglyceride-/free cholesterol-OOH were significantly elevated in PD versus HD patients, regardless of patients' underlying medical conditions, sex, age, PD type, clinical biochemical markers and medication. It should be noted that all fractionated lipid-OOH levels were inversely correlated with LDL-P concentration, while LDL-P concentration was not correlated with LDL-C in PD patients. Moreover, LDL carotenoids were significantly lower in PD patients versus control. The increased levels of oxLDL status specific markers in both PD and HD patients (compared to control), support a potential prognostic value of oxLDL regarding CVD risk assessment in both patient groups. Lastly, the study introduces the oxLDL peroxidation markers free cholesterol-OOH and cholesteryl ester-OOH as complementary to LDL-P number, and as possible alternatives to LDL-C., Competing Interests: Declaration of competing interest The authors declare to be in a relationship with State Scholarship Foundation (IKY) (Personal Scholarship awarded by IKY Foundation’s program “Scholarship Program for PhD candidates in the Greek Universities”), (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
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24. Methods on LDL particle isolation, characterization, and component fractionation for the development of novel specific oxidized LDL status markers for atherosclerotic disease risk assessment.
- Author
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Papadea P, Skipitari M, Kalaitzopoulou E, Varemmenou A, Spiliopoulou M, Papasotiriou M, Papachristou E, Goumenos D, Onoufriou A, Rosmaraki E, Margiolaki I, and Georgiou CD
- Abstract
The present study uses simple, innovative methods to isolate, characterize and fractionate LDL in its main components for the study of specific oxidations on them that characterize oxidized low-density lipoprotein (oxLDL) status, as it causatively relates to atherosclerosis-associated cardiovascular disease (CVD) risk assessment. These methods are: (a) A simple, relatively time-short, low cost protocol for LDL isolation, to avoid shortcomings of the currently employed ultracentrifugation and affinity chromatography methodologies. (b) LDL purity verification by apoB100 SDS-PAGE analysis and by LDL particle size determination; the latter and its serum concentration are determined in the present study by a simple method more clinically feasible as marker of CVD risk assessment than nuclear magnetic resonance. (c) A protocol for LDL fractionation, for the first time, into its main protein/lipid components (apoB100, phospholipids, triglycerides, free cholesterol, and cholesteryl esters), as well as into LDL carotenoid/tocopherol content. (d) Protocols for the measurement, for the first time, of indicative specific LDL component oxidative modifications (cholesteryl ester-OOH, triglyceride-OOH, free cholesterol-OOH, phospholipid-OOH, apoB100-MDA, and apoB100-DiTyr) out of the many (known/unknown/under development) that collectively define oxLDL status, which contrasts with the current non-specific oxLDL status evaluation methods. The indicative oxLDL status markers, selected in the present study on the basis of expressing early oxidative stress-induced oxidative effects on LDL, are studied for the first time on patients with end stage kidney disease on maintenance hemodialysis, selected as an indicative model for atherosclerosis associated diseases. Isolating LDL and fractionating its protein and main lipid components, as well as its antioxidant arsenal comprised of carotenoids and tocopherols, paves the way for future studies to investigate all possible oxidative modifications responsible for turning LDL to oxLDL in association to their possible escaping from LDL's internal antioxidant defense. This can lead to studies to identify those oxidative modifications of oxLDL (after their artificial generation on LDL), which are recognized by macrophages and convert them to foam cells, known to be responsible for the formation of atherosclerotic plaques that lead to the various CVDs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Papadea, Skipitari, Kalaitzopoulou, Varemmenou, Spiliopoulou, Papasotiriou, Papachristou, Goumenos, Onoufriou, Rosmaraki, Margiolaki and Georgiou.)
- Published
- 2023
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25. Time-Related Evidence of Intestinal Oxidative Stress in Obstructive Jaundice-Induced Rats.
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Angelis A, Kostakis ID, Lilimpakis K, Kalaitzopoulou E, Papadea P, Skipitari M, Georgiou CD, and Vagianos C
- Subjects
- Rats, Animals, Intestines, Rats, Wistar, Endotoxins metabolism, Oxidative Stress, Ligation, Liver metabolism, Jaundice, Obstructive metabolism
- Abstract
Introduction: Obstructive jaundice is known to affect intestinal permeability and facilitate bacterial translocation through related mechanisms. This study was conducted to evaluate the alterations concerning blood biochemistry and levels of several markers of oxidative stress (OS) in blood and intestinal mucosa caused by obstructive jaundice and how these fluctuate over time, in order to further explore the possibility of intervening in the OS path in future experiments., Methods: A total of 54 albino Wistar rats were randomly divided into three groups (control, sham operated, and bile duct ligation) and sacrificed at specific time intervals (12 h and 2, 7, and 14 days). The intestinal barrier function was evaluated by measuring endotoxin levels in portal, aortic, and peripheral blood. Also, basic biochemical parameters were simultaneously measured in peripheral blood. Tissue samples collected from the terminal ileum were homogenized for determining the OS markers, lipid peroxidation, and protein-free radical-induced oxidation., Results: We designed this experiment to examine the alterations in enteric mucosa primarily in relation to OS in a period of 14 days. During this time period, we investigated in specific time intervals not only OS fluctuations but also other liver function parameters, as well as CRP and endotoxin levels. The alterations were monitored in relation to time after bile duct ligation., Conclusion: Bile duct ligation in rats causes OS versus post-ligation time progression of the common bile duct. OS was increased by ∼50% compared to control/sham and peaked at 7 days and at least up to 14 days post-ligation. This phenomenon was accompanied with a deranging of liver function after ligation, as anticipated, but not in all measured parameters; biochemical and endotoxin levels followed the same pattern., (© 2023 The Author(s). Published by S. Karger AG, Basel.)
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- 2023
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26. Maternal Calorie Restriction Induces a Transcriptional Cytoprotective Response in Embryonic Liver Partially Dependent on Nrf2.
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Habeos GI, Filippopoulou F, Habeos EE, Kalaitzopoulou E, Skipitari M, Papadea P, Lagoumintzis G, Niarchos A, Georgiou CD, and Chartoumpekis DV
- Abstract
Background: Calorie restriction is known to enhance Nrf2 signaling and longevity in adult mice, partially by reducing reactive oxygen species, but calorie restriction during pregnancy leads to intrauterine growth retardation. The latter is associated with fetal reprogramming leading to increased incidence of obesity, metabolic syndrome and diabetes in adult life. Transcription factor Nrf2 is a central regulator of the antioxidant response and its crosstalk with metabolic pathways is emerging. We hypothesized that the Nrf2 pathway is induced in embryos during calorie restriction in pregnant mothers., Methods: From gestational day 10 up to day 16, 50% of the necessary mouse diet was provided to Nrf2 heterozygous pregnant females with fathers being of the same genotype. Embryos were harvested at the end of gestational day 16 and fetal liver was used for qRT-PCR and assessment of oxidative stress (OS)., Results: Intrauterine calorie restriction led to upregulation of mRNA expression of antioxidant genes ( Nqo1 , Gsta1 , Gsta4 ) and of genes related to integrated stress response ( Chac1 , Ddit3 ) in WT embryos. The expression of a key gluconeogenic ( G6pase ) and two lipogenic genes ( Acacb , Fasn ) was repressed in calorie-restricted embryos. In Nrf2 knockout embryos, the induction of Nqo1 and Gsta1 genes was abrogated while that of Gsta4 was preserved, indicating an at least partially Nrf2-dependent induction of antioxidant genes after in utero calorie restriction. Measures of OS showed no difference (superoxide radical and malondialdehyde) or a small decrease (thiobarbituric reactive substances) in calorie-restricted WT embryos., Conclusions: Calorie restriction during pregnancy elicits the transcriptional induction of cytoprotective/antioxidant genes in the fetal liver, which is at least partially Nrf2-dependent, with a physiological significance that warrants further investigation.
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- 2022
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27. Detection of superoxide radical in all biological systems by Thin Layer Chromatography.
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Zisimopoulos DN, Kalaitzopoulou E, Skipitari M, Papadea P, Panagopoulos NT, Salahas G, and Georgiou CD
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- Animals, Brain, Brassica chemistry, Cell Line, Chromatography, Thin Layer methods, Ethidium analysis, Heart, Limit of Detection, Lung, Mice, Octoxynol chemistry, Oxidative Stress, Spleen, Cell Extracts analysis, Ethidium analogs & derivatives, Superoxides analysis
- Abstract
The study presents a new method that detects O
2 •- , via quantification of 2-hydroxyethidium (2-ΟΗ-Ε+ ) as low as ∼30 fmoles by High-Performance Thin Layer Chromatography (HPTLC). The method isolates 2-ΟΗ-Ε+ after its extraction by the anionic detergent SDS (at 18-fold higher than its CMC) together with certain organic/inorganic reagents, and its HPTLC-separation from di-ethidium (di-Ε+ ) and ethidium (Ε+ ). Quantification of 2-OH-E+ is based on its ex/em maxima at 290/540 nm, and of di-E+ and E+ at 295/545 nm. The major innovations of the present method are the development of protocols for (i) efficient extraction (by SDS) and (ii) sensitive quantification (by HPTLC) for 2-OH-E+ (as well as di-E+ and E+ ) from most biological systems (animals, plants, cells, subcellular compartments, fluids). The method extracts 2-ΟΗ-Ε+ (by neutralizing the strong binding between its quaternary N+ and negatively charged sites on phospholipids, DNA etc) together with free HE, while protects both from biological oxidases, and also extracts/quantifies total proteins (hydrophilic and hydrophobic) for expressing O2 •- levels per protein quantity. The method also uses SDS (at 80-fold lower than its CMC) to extract/remove/wash 2-ΟΗ-Ε+ from cell/organelle exterior membrane sites, for more accurate internal content quantification. The new method is applied on indicative biological systems: (1) artificially stressed (mouse organs and liver mitochondria and nuclei, ±exposed to paraquat, a known O2 •- generator), and (2) physiologically stressed (cauliflower plant, exposed to light/dark)., (Copyright © 2021 Elsevier Inc. All rights reserved.)- Published
- 2022
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28. Oxidized lipid-associated protein damage in children and adolescents with type 1 diabetes mellitus: New diagnostic/prognostic clinical markers.
- Author
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Kostopoulou E, Kalaitzopoulou E, Papadea P, Skipitari M, Rojas Gil AP, Spiliotis BE, and Georgiou CD
- Subjects
- Adolescent, Biomarkers blood, Case-Control Studies, Child, Child, Preschool, Female, Humans, Male, Diabetes Mellitus, Type 1 blood, Lipid Peroxidation, Lipid Peroxides blood, Proteins metabolism, Thiobarbituric Acid Reactive Substances metabolism
- Abstract
Background: Type 1 diabetes mellitus (DM1), a chronic metabolic disorder of autoimmune origin, has been associated with oxidative stress (OS), which plays a central role in the onset, progression, and long-term complications of DM1. The markers of OS lipid peroxidation products, lipid hydroperoxides (LOOH), and also malondialdehyde (MDA) and thiobarbituric reactive substances (TBARS) that oxidatively modify proteins (Pr) (i.e., PrMDA and PrTBARS, respectively), have been associated with DM2, DM1, diabetic neuropathy, and microalbuminuria., Objective/subjects: Here, we investigated LOOH, PrMDA and PrTBARS in 50 children and adolescents with DM1 and 21 controls., Results: The novel OS marker PrTBARS was assessed for the first time in children and adolescents with DM1. LOOH and the pair PrMDA/PrTBARS, representing early and late peroxidation stages, respectively, are found to be significantly higher (130%, 50/90%, respectively, at p < 0.001) in patients with DM1 compared to controls. The studied OS parameters did not differ with age, age at diagnosis, sex, duration of DM1, presence of recent ketosis/ketoacidosis, or mode of treatment., Conclusions: We propose that LOOH, PrMDA and the new marker PrTBARS could serve as potential diagnostic clinical markers for identifying OS in children and adolescents with DM1, and may, perhaps, hold promise as a prognostic tool for future complications associated with the disease., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2021
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29. Histological grading in primary membranous nephropathy is essential for clinical management and predicts outcome of patients.
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Stangou MJ, Marinaki S, Papachristou E, Liapis G, Pateinakis P, Gakiopoulou H, Nikolaidou C, Kolovou K, Lampropoulou IT, Zerbala S, Papadea P, Dounousi E, Balafa O, Pavlakou P, Andrikos A, Balassi E, Manolakaki P, Moustakas G, Galitsiou D, Mitsopoulos E, Vourlakou C, Choulitoudi V, Andronikidi PE, Stefanidis I, Golfinopoulos S, Dafnis E, Stylianou K, Panagoutsos S, Papadogianakis A, Tzanakis I, Sioulis A, Vlahakos D, Grapsa I, Tsilivigkou M, Kaperonis N, Paliouras C, Dioudis C, Spaia S, Apostolou T, Iatrou C, Boletis J, Goumenos D, and Papagianni A
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Biopsy, Female, Histocytochemistry, Humans, Immunosuppressive Agents therapeutic use, Kidney Diseases diagnosis, Kidney Diseases therapy, Male, Middle Aged, Prognosis, Retrospective Studies, Young Adult, Glomerulonephritis, Membranous diagnosis, Glomerulonephritis, Membranous pathology, Glomerulonephritis, Membranous therapy, Kidney pathology, Kidney Diseases pathology
- Abstract
Aims: Diagnosis of primary membranous nephropathy (PMN) is mainly based on immunofluorescence/immunohistochemistry findings. However, assessment of specific features on optical microscopy can help to estimate the severity of the disease, guide treatment and predict the response. The aim of this study was to identify, classify and grade the precise histological findings in PMN to predict renal function outcome and guide treatment., Methods and Results: Histological parameters, including focal segmental sclerosis (FSGS), tubular atrophy (TA), interstitial fibrosis (IF) and vascular hyalinosis (VH), were re-evaluated in 752 patients with PMN. Their predictive value was estimated separately, and also in a combination score (FSTIV) graded from 0 to 4. Finally, the impact of histology was assessed in the response to immunosuppressive treatment. Mean age of patients was 53.3 (15-85) years and most presented with nephrotic syndrome. FSGS was present in 32% and VH in 51% of the patients, while TA and IF were graded as stage ≥1 in 52% and 51.4%, respectively. The follow-up period was 122.3 (112-376) months. FSGS, TA and IF and VH were associated with impaired renal function at diagnosis (P = 0.02, P < 0.0001, P = 0.001 and P = 0.02, respectively) and at the end of follow-up (P = 0.004, P < 0.0001, P < 0.0001 and P = 0.04, respectively). In multiple regression and binary logistic analysis, the presence of FSGS and degree of TA were the most significant parameters predicting renal function outcome, defined either by eGFR (end), FSGS (r = 0.6, P < 0.0001) and TA (r = 0.6, P < 0.0001), or by the endpoint of >50% eGFR reduction, FSGS (P = 0.001) and TA (P = 0.02). Also, patients presented with FSGS, IF, VH and/or with FSTIV > 1 could benefit from immunosuppression, regardless of clinical presentation., Conclusions: The presence and degree of four histological indices, FSGS, VH, TA and IF, assessed separately or in combination, and FSTIV score not only predict renal function outcome after long-term follow-up, but can also help in the choice of appropriate treatment. Decisions concerning immunosuppressive treatment can be guided by pathology regardless of clinical findings., (© 2019 The Authors. Histopathology published by John Wiley & Sons Ltd.)
- Published
- 2019
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30. The Oxygen Release Instrument: Space Mission Reactive Oxygen Species Measurements for Habitability Characterization, Biosignature Preservation Potential Assessment, and Evaluation of Human Health Hazards.
- Author
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Georgiou CD, McKay CP, Quinn RC, Kalaitzopoulou E, Papadea P, and Skipitari M
- Abstract
We describe the design of an instrument, the OxR (for Oxygen Release), for the enzymatically specific and non-enzymatic detection and quantification of the reactive oxidant species (ROS), superoxide radicals (O
2 •- ), and peroxides (O2 2- , e.g., H2 O2 ) on the surface of Mars and Moon. The OxR instrument is designed to characterize planetary habitability, evaluate human health hazards, and identify sites with high biosignature preservation potential. The instrument can also be used for missions to the icy satellites of Saturn's Titan and Enceladus, and Jupiter's Europa. The principle of the OxR instrument is based on the conversion of (i) O2 •- to O2 via its enzymatic dismutation (which also releases H2 O2 ), and of (ii) H2 O2 (free or released by the hydrolysis of peroxides and by the dismutation of O2 •- ) to O2 via enzymatic decomposition. At stages i and ii, released O2 is quantitatively detected by an O2 sensor and stoichiometrically converted to moles of O2 •- and H2 O2 . A non-enzymatic alternative approach is also designed. These methods serve as the design basis for the construction of a new small-footprint instrument for specific oxidant detection. The minimum detection limit of the OxR instrument for O2 •- and O2 2- in Mars, Lunar, and Titan regolith, and in Europa and Enceladus ice is projected to be 10 ppb. The methodology of the OxR instrument can be rapidly advanced to flight readiness by leveraging the Phoenix Wet Chemical Laboratory, or microfluidic sample processing technologies.- Published
- 2019
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31. Immunosuppressive regimens based on Cyclophospamide or Calcineurin inhibitors: Comparison of their effect in the long term outcome of Primary Membranous Nephropathy.
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Stangou M, Marinaki S, Papachristou E, Kolovou K, Sambani E, Zerbala S, Papadea P, Balafa O, Rapsomanikis KP, Andrikos A, Manolakaki P, Papadopoulou D, Mitsopoulos E, Liakou H, Andronikidi PE, Choulitoudi V, Moustakas G, Galitsiou D, Dafnis E, Stylianou K, Stefanidis I, Golfinopoulos S, Panagoutsos S, Tsilivigkou M, Papadogianakis A, Tzanakis I, Sioulis A, Vlachakos D, Grapsa E, Spaia S, Kaperonis N, Paliouras C, Dioudis C, Papoulidou F, Apostolou T, Iatrou C, Boletis I, Goumenos D, and Papagianni A
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Retrospective Studies, Treatment Outcome, Young Adult, Calcineurin Inhibitors therapeutic use, Cyclophosphamide therapeutic use, Glomerulonephritis, Membranous drug therapy, Immunosuppressive Agents therapeutic use
- Abstract
Introduction: Management of the Primary Membranous Nephropathy (PMN) usually involves administration of immunosuppressives. Cyclophosphamide (Cyclo) and Calcineurin Inhibitors (CNIs) are both widely used but only limited data exist to compare their efficacy in long term follow-up., Aim: The aim of the present study was to estimate and compare long term effects of Cyclo and CNIs in patients with PMN., Patients-Methods: Clinical data, histologic findings and long term outcome were retrospectively studied. The response to treatment and rate of relapse was compared between patients treated with CNIs or Cyclo based immunosuppressive regimens., Results: Twenty three centers participated in the study, with 752 PMN patients (Mean age 53.4(14-87) yrs, M/F 467/285), followed for 10.1±5.7 years. All patients were initially treated with Renin Angiotensin Aldosterone System inhibitors (RAASi) for at least 6 months. Based on their response and tolerance to initial treatment, patients were divided into 3 groups, group I with spontaneous remission, who had no further treatment, group II, continued on RAASi only, and group III on RAASi+immunosuppression. Immunosuppressive regimes were mainly based on CNIs or Cyclo. Frequent relapses and failure to treatment were more common between patients who had started on CNIs (n = 381) compared to those initially treated with Cyclo (n = 110), relapse rate: 25.2% vs. 6.4%, p<0.0001, and no response rate: 22.5% vs. 13.6%, p = 0.04, respectively., Conclusions: Long term follow up showed that administration of Cyclo in PMN is followed by better preservation of renal function, increased response rate and less frequent relapses, compared to CNIs., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
- Full Text
- View/download PDF
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