46 results on '"Volakakis N"'
Search Results
2. Quantitative proteomics to study the response of potato to contrasting fertilisation regimes
- Author
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Rempelos, L., Cooper, J., Wilcockson, S., Eyre, M., Shotton, P., Volakakis, N., Orr, C. H., Leifert, C., Gatehouse, A. M. R., and Tétard-Jones, C.
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- 2013
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3. Respiratory resistance during anaesthesia with isoflurane, sevoflurane, and desflurane: a randomized clinical trial
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Nyktari, V., Papaioannou, A., Volakakis, N., Lappa, A., Margaritsanaki, P., and Askitopoulou, H.
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- 2011
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4. Integrating the use of resistant rootstocks/cultivars, suppressive composts and elicitors to improve yields and quality in protected organic cultivation systems
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Willson, A., primary, Goltz, M., additional, Markellou, E., additional, Volakakis, N., additional, and Leifert, C., additional
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- 2020
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5. Control of enteric pathogens in ready-to-eat vegetable crops in organic and ‘low input’ production systems: a HACCP-based approach
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Leifert, C., Ball, K., Volakakis, N., and Cooper, J. M.
- Published
- 2008
6. Real-World Data on Health-Related Quality of Life Assessment in Patients With Breast Cancer Receiving Subcutaneous Trastuzumab
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Syrios, J. Pappa, E. Volakakis, N. Grivas, A. Alafis, J. Manioudaki, S. Tzouda, V. Korogiannos, A. Rapti, C. Koufopoulos, N. Nikolaidou, A. Kanavou, E. Alexopoulos, A. Koumarianou, A.
- Subjects
skin and connective tissue diseases ,neoplasms - Abstract
Purpose: Trastuzumab, a humanized anti-human epidermal growth factor receptor 2 (anti-HER2) antibody delivered intravenously, has revolutionized the treatment of patients with breast cancer overexpressing HER2 protein. Recently, a newer subcutaneous formulation was shown to have comparable efficacy to the initial intravenous trastuzumab. In this study, we aimed to evaluate the impact of subcutaneous trastuzumab on the health-related quality of life (HRQoL) of patients diagnosed with early or metastatic HER2-overexpressing breast cancer. Methods: Patients were provided with the EORTC QLQ-C30 (European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30) and the BR-23 questionnaires. The scoring of questionnaires and patient’s sociodemographic and clinicopathologic characteristics were recorded and analyzed by descriptive and correlation statistics employing t test and 2-way analysis of variance. Results: A total of 163 patients agreed to participate in the study. About 90 of 163 patients (55.21%) received subcutaneous trastuzumab and 21 patients intravenous trastuzumab (12.88%). A control group of 52 HER2+ patients received chemotherapy without trastuzumab (31.90%). Patients receiving subcutaneous trastuzumab were older and of more advanced disease stage compared with those receiving chemotherapy (58.5 vs 51 years, 39.8% vs 28.8% advanced disease). In univariate analysis, subcutaneous trastuzumab was associated with less nausea and vomiting (P =.002) but worse cognitive function (P =.013) and dyspnea (P =.042). Patients who have received >8 cycles of subcutaneous trastuzumab reported less diarrhea (P =.049) and systemic therapy side effects (P =.015). Multivariate analysis showed that patients without comorbidity receiving subcutaneous trastuzumab had less treatment side effects, less upset by hair loss, and higher emotional functioning. Of note, mastectomy and subcutaneous trastuzumab were associated with improved role functioning (P =.021). In metastatic disease, no negative impact of subcutaneous trastuzumab on HRQoL was found. Conclusions: The administration of subcutaneous trastuzumab improved certain symptoms and did not adversely affect most of the assessed functional scales. Particularly, in the metastatic setting, subcutaneous trastuzumab had no negative impact on HRQoL. © The Author(s) 2018.
- Published
- 2018
7. Alterations of p11 in brain tissue and peripheral blood leukocytes in Parkinson's disease
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Green H, Zhang X, Tiklova K, Volakakis N, Brodin L, Berg L, Greengard P, Perlmann T, and Svenningsson P
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congenital, hereditary, and neonatal diseases and abnormalities - Abstract
Individuals with Parkinson's disease (PD) often suffer from comorbid depression. P11 (S100A10), a member of the S100 family of proteins, is expressed widely throughout the body and is involved in major depressive disorder and antidepressant response. Central p11 levels are reduced in postmortem tissue from depressed individuals; however, p11 has not yet been investigated in PD patients with depression or those without depression. We investigated p11 levels in postmortem PD brains and assessed whether peripheral p11 levels correlate with disease severity. Substantia nigra, putamen, and cortical p11 protein levels were assessed in postmortem brain samples from PD patients and matched controls. In a different set of postmortem brains, p11 mRNA expression was measured in dopaminergic cells from the substantia nigra. Both p11 protein and mRNA levels were decreased in PD patients. Peripheral p11 protein levels were investigated in distinct leukocyte populations from PD patients with depression and those without depression. Monocyte, natural killer (NK) cell, and cytotoxic T-cell p11 levels were positively associated with the severity of PD, and NK cell p11 levels were positively associated with depression scores. Given that inflammation plays a role in both PD and depression, it is intriguing that peripheral p11 levels are altered in immune cells in both conditions. Our data provide insight into the pathological alterations occurring centrally and peripherally in PD. Moreover, if replicated in other cohorts, p11 could be an easily accessible biomarker for monitoring the severity of PD, especially in the context of comorbid depression.
- Published
- 2017
8. Soil arthropod community in the olive agroecosystem: determined by environment and farming practices in different management systems and agroecological zones
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Gkisakis, Vasileios, Volakakis, N., Kollaros, D., Barberi, Paolo, and Kabourakis, E. M.
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- 2016
9. Quantitative proteomics to study the response of potato to contrasting fertilisation regimes
- Author
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Rempelos, L., Cooper, J., Wilcockson, S., Eyre, M., Shotton, P., Volakakis, N., Orr, C. H., Leifert, C., Gatehouse, A. M. R., and Tétard-Jones, C.
- Subjects
0106 biological sciences ,0303 health sciences ,03 medical and health sciences ,Genetics ,Plant Science ,01 natural sciences ,Agronomy and Crop Science ,Molecular Biology ,030304 developmental biology ,010606 plant biology & botany ,Biotechnology - Published
- 2012
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10. Nurr1 and Retinoid X Receptor Ligands Stimulate Ret Signaling in Dopamine Neurons and Can Alleviate -Synuclein Disrupted Gene Expression
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Volakakis, N., primary, Tiklova, K., additional, Decressac, M., additional, Papathanou, M., additional, Mattsson, B., additional, Gillberg, L., additional, Nobre, A., additional, Bjorklund, A., additional, and Perlmann, T., additional
- Published
- 2015
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11. The Effects of Crop Type and Production Systems on the Activity of Beneficial Invertebrates
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Eyre, M.D., Volakakis, N., Shotton, P.N., and Leifert, C.
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Crop combinations and interactions ,fungi ,Biodiversity and ecosystem services ,food and beverages ,Farming Systems - Abstract
Beneficial invertebrate activity (13 groups) was assessed in five crop types on a split-plot experimental system in northern England using pitfall trapping and suction sampling in May-October 2005. Very significant differences were detected in activity between crop type, and in the preference of groups for individual crops. Within crop types, differences in fertiliser and crop protection approaches appeared to significantly affect activity, with preferences for either organic or conventional management differing between groups. In general, inorganic fertiliser application had more effect on activity than pesticide, herbicide and fungicide use.
- Published
- 2007
12. Olive FlyBactrocera oleae(Diptera, Tephritidae) Activity and Fruit Infestation Under Mass Trapping in an Organic Table Olive Orchard in Crete, Greece
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Volakakis, N. G., primary, Eyre, M. D., additional, and Kabourakis, E. M., additional
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- 2012
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13. Basic life support skill retention by medical students: a comparison of two teaching curricula
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Papaioannou, A., primary, Fraidakis, O., additional, Volakakis, N., additional, Stefanakis, G., additional, Bimpaki, E., additional, Pagkalos, J., additional, Psarologakis, C., additional, Aggouridakis, P., additional, and Askitopoulou, H., additional
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- 2010
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14. Effect of two different MAC concentrations of desflurane and sevoflurane on pulmonary resistance during anesthesia
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Nyktari, V., primary, Papaioannou, A., additional, Lappa, A., additional, Volakakis, N., additional, and Askitopoulou, H., additional
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- 2008
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15. Gastrointestinal Metastases From Lobular Breast Carcinoma: A Literature Review.
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Kioleoglou Z, Georgaki E, Koufopoulos N, Kostek O, Volakakis N, Dimitriadou A, and Kokkali S
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Invasive lobular carcinoma (ILC) represents a rare subtype of breast carcinoma, originating from the lobule. Unlike ductal carcinoma, ILC does not express E-cadherin and thus can metastasize to uncommon sites. We aimed to investigate the clinicopathological characteristics of the rare subgroup of ILC patients with gastrointestinal (GI) metastases. A PubMed search was undertaken using the terms "Lobular Breast Carcinoma" AND "Gastrointestinal Metastasis." We identified 169 cases, with metachronous GI metastatic disease being approximately twice as common as synchronous GI metastases. The median age at initial diagnosis was 56.7 years (24-88). The majority of patients were hormonal receptor-positive and only a small minority was HER2-positive. The appearance of a gastrointestinal lesion was often the mode of revelation of ILC. Differential diagnosis from primary gastrointestinal cancer is sometimes challenging, especially in the case of signet-ring cell carcinoma. The median time from breast cancer diagnosis to GI metastases was 6.5 years (0-33). Most common metastatic sites include the stomach, colon, and rectum, in order of decreasing frequency, whereas metastases were found in every part of the digestive tract. In conclusion, metastases of ILC can arise in the gastrointestinal tract and they should be managed similarly to metastatic breast cancer., Competing Interests: Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Kioleoglou et al.)
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- 2024
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16. Mycotoxin contamination in organic and conventional cereal grain and products: A systematic literature review and meta-analysis.
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Wang J, Sufar EK, Bernhoft A, Seal C, Rempelos L, Hasanaliyeva G, Zhao B, Iversen PO, Baranski M, Volakakis N, and Leifert C
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- Fusarium chemistry, Food, Organic analysis, Food, Organic microbiology, Edible Grain chemistry, Edible Grain microbiology, Mycotoxins analysis, Food Contamination analysis
- Abstract
There is still considerable controversy about the relative risk of mycotoxin exposure associated with the consumption of organic and conventional cereals. Using validated protocols, we carried out a systematic literature review and meta-analyses of data on the incidence and concentrations of mycotoxins produced by Fusarium, Claviceps, Penicillium, and Aspergillus species in organic and conventional cereal grains/products. The standard weighted meta-analysis of concentration data detected a significant effect of production system (organic vs. conventional) only for the Fusarium mycotoxins deoxynivalenol, with concentrations ∼50% higher in conventional than organic cereal grains/products (p < 0.0001). Weighted meta-analyses of incidence data and unweighted meta-analyses of concentration data also detected small, but significant effects of production system on the incidence and/or concentrations of T-2/HT-2 toxins, zearalenone, enniatin, beauvericin, ochratoxin A (OTA), and aflatoxins. Multilevel meta-analyses identified climatic conditions, cereal species, study type, and analytical methods used as important confounding factors for the effects of production system. Overall, results from this study suggest that (i) Fusarium mycotoxin contamination decreased between the 1990s and 2020, (ii) contamination levels are similar in organic and conventional cereals used for human consumption, and (iii) maintaining OTA concentrations below the maximum contamination levels (3.0 μg/kg) set by the EU remains a major challenge., (© 2024 The Authors. Comprehensive Reviews in Food Science and Food Safety published by Wiley Periodicals LLC on behalf of Institute of Food Technologists.)
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- 2024
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17. Optimal Volume Assessment for Serous Fluid Cytology.
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Christofidis K, Theochari M, Mavropoulos Papoudas S, Kiohou L, Sousouris S, Dimitriadou A, Volakakis N, Maounis N, and Mikou P
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Objective: This study aimed to investigate the optimal volume of serous fluid needed for accurate diagnosis using The International System for Reporting Serous Fluid Cytopathology (TIS), as well as to provide information on the distribution of serous effusion cases in the TIS categories (ND: non-diagnostic, NFM: negative for malignancy, AUS: atypia of undetermined significance, SFM: suspicious for malignancy, MAL: malignant) and relevant epidemiological data., Methods: A retrospective analysis of 2340 serous effusion cases (pleural, peritoneal, and pericardial) from two hospitals between 2018 and 2020 was conducted. TIS categories were assigned to each case, and for 1181 cases, these were correlated with the volume of the analyzed fluid., Results: Our study found statistically significant differences in volume distributions between certain TIS categories. Statistically lower volumes were observed in NFM compared to MAL, in UNCERTAIN (ND, AUS, SFM) compared to both MAL and NFM, and in NOT MAL (ND, NFM, AUS, SFM) compared to MAL. However, these differences were not substantial enough to hold any clinical relevance., Conclusions: This study suggests that while fluid volume may slightly influence the TIS category, it does not impact the diagnostic accuracy of serous effusion cytology. Therefore, the ideal serous effusion specimen volume can be defined solely by practical parameters.
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- 2024
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18. Effects of Agricultural Intensification on Mediterranean Diets: A Narrative Review.
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Hasanaliyeva G, Sufar EK, Wang J, Rempelos L, Volakakis N, Iversen PO, and Leifert C
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Introduction: Mediterranean diets (MedDiets) are linked to substantial health benefits. However, there is also growing evidence that the intensification of food production over the last 60 years has resulted in nutritionally relevant changes in the composition of foods that may augment the health benefits of MedDiets., Objective: To synthesize, summarize, and critically evaluate the currently available evidence for changes in food composition resulting from agricultural intensification practices and their potential impact on the health benefits of MedDiets., Methods: We summarized/synthesized information from (i) systematic literature reviews/meta-analyses and more recently published articles on composition differences between conventional and organic foods, (ii) desk studies which compared food composition data from before and after agricultural intensification, (iii) recent retail and farm surveys and/or factorial field experiments that identified specific agronomic practices responsible for nutritionally relevant changes in food composition, and (iv) a recent systematic literature review and a small number of subsequently published observational and dietary intervention studies that investigated the potential health impacts of changes in food composition resulting from agricultural intensification., Results and Discussion: There has been growing evidence that the intensification of food production has resulted in (i) lower concentrations of nutritionally desirable compounds (e.g., phenolics, certain vitamins, mineral micronutrients including Se, Zn, and omega-3 fatty acids, α-tocopherol) and/or (ii) higher concentrations of nutritionally undesirable or toxic compounds (pesticide residues, cadmium, omega-6 fatty acids) in many of the foods (including wholegrain cereals, fruit and vegetables, olive oil, dairy products and meat from small ruminants, and fish) that are thought to contribute to the health benefits associated with MedDiets. The evidence for negative health impacts of consuming foods from intensified conventional production systems has also increased but is still limited and based primarily on evidence from observational studies. Limitations and gaps in the current evidence base are discussed. Conclusions: There is now substantial evidence that the intensification of agricultural food production has resulted in a decline in the nutritional quality of many of the foods that are recognized to contribute to the positive health impacts associated with adhering to traditional MedDiets. Further research is needed to quantify to what extent this decline augments the positive health impacts of adhering to a traditional MedDiet.
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- 2023
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19. Breeding Bread-Making Wheat Varieties for Organic Farming Systems: The Need to Target Productivity, Robustness, Resource Use Efficiency and Grain Quality Traits.
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Rempelos L, Wang J, Sufar EK, Almuayrifi MSB, Knutt D, Leifert H, Leifert A, Wilkinson A, Shotton P, Hasanaliyeva G, Bilsborrow P, Wilcockson S, Volakakis N, Markellou E, Zhao B, Jones S, Iversen PO, and Leifert C
- Abstract
Agronomic protocols (rotation, tillage, fertilization and crop protection) commonly used in organic and conventional crop production differ significantly and there is evidence that modern varieties developed for conventional high-input farming systems do not have the combination of traits required for optimum performance in organic farming systems. Specifically, there is evidence that prohibition on the use of water-soluble, mineral N, P and K fertilizers and synthetic pesticide inputs in organic farming results in a need to revise both breeding and selection protocols. For organic production systems, the focus needs to be on the following: (i) traits prioritized by organic farmers such as high nutrient use efficiency from organic fertilizer inputs, competitiveness against weeds, and pest and disease resistance, (ii) processing quality parameters defined by millers and bakers and (iii) nutritional quality parameters demanded by organic consumers. In this article, we review evidence from variety trials and factorial field experiments that (i) studied to what extent there is a need for organic farming focused breeding programs, (ii) investigated which traits/trait combinations should be targeted in these breeding programs and/or (iii) compared the performance of modern varieties developed for the conventional sector with traditional/older varieties favored by organic farmers and/or new varieties developed in organic farming focused breeding programs. Our review focuses on wheat because there have been organic and/or low-input farming focused wheat breeding programs for more than 20 years in Europe, which has allowed the performance of varieties/genotypes from organic/low-input and conventional farming focused breeding programs to be compared.
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- 2023
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20. Diet, but not food type, significantly affects micronutrient and toxic metal profiles in urine and/or plasma; a randomized, controlled intervention trial.
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Rempelos L, Wang J, Barański M, Watson A, Volakakis N, Hadall C, Hasanaliyeva G, Chatzidimitriou E, Magistrali A, Davis H, Vigar V, Średnicka-Tober D, Rushton S, Rosnes KS, Iversen PO, Seal CJ, and Leifert C
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- Animals, Humans, Micronutrients, Diet, Vegetables, Fruit, Diet, Mediterranean, Trace Elements
- Abstract
Background: Observational studies have linked Mediterranean Diets (MedDiets) and organic food consumption with positive health outcomes, which may be explained by higher mineral micronutrient and phenolic intake and lower dietary exposure to toxic compounds., Objectives: We aimed to determine the effects of diet and food type (organic compared with conventional) on urinary excretion (UE) and/or plasma concentrations of mineral micronutrients, phenolics, and toxic metals., Methods: Healthy adult participants were randomly allocated to a conventional (n = 14) or an intervention (n = 13) group. During a 2-wk period, the intervention group consumed a MedDiet made entirely from organic foods, whereas the conventional group consumed a MedDiet made from conventional foods. Before and after the intervention period, both groups consumed their habitual Western diets made from conventional foods. The primary outcome was UE and/or plasma concentrations of selected mineral micronutrients, toxic metals, and phenolic markers. In addition, we monitored diets using food diaries. The participants were aware of study group assignment, but the study assessors were not., Results: Changing from a Western Diet to a MedDiet for 2 wk resulted in significant increases in UE of total phenolics and salicylic acid (by 46% and 45%, respectively), the mineral micronutrients Co, I, and Mn (by 211%, 70%, and 102%, respectively), and the toxic metal Ni (by 42%), and plasma Se concentrations (by 14%). However, no significant effects of food type (organic compared with conventional) were detected. Redundancy analysis identified vegetables, coffee, wine, and fruit as positive drivers for UE of phenolic markers and mineral micronutrients, and fish consumption as a positive driver for UE of Cd and Pb., Conclusions: Although small effects of food type cannot be ruled out, our study suggests that only changing to a MedDiet with higher fruit and vegetable, and lower meat, consumption results in a large increase in phenolic and mineral micronutrient intakes. This trial was registered at clinicaltrials.gov as NCT03254537., (Copyright © 2022 American Society for Nutrition.)
- Published
- 2022
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21. Diet and food type affect urinary pesticide residue excretion profiles in healthy individuals: results of a randomized controlled dietary intervention trial.
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Rempelos L, Wang J, Barański M, Watson A, Volakakis N, Hoppe HW, Kühn-Velten WN, Hadall C, Hasanaliyeva G, Chatzidimitriou E, Magistrali A, Davis H, Vigar V, Średnicka-Tober D, Rushton S, Iversen PO, Seal CJ, and Leifert C
- Subjects
- Adult, Female, Healthy Volunteers, Humans, Male, Pesticides toxicity, Sex Factors, Young Adult, Diet, Mediterranean adverse effects, Diet, Western adverse effects, Dietary Exposure adverse effects, Food, Organic adverse effects, Pesticide Residues urine
- Abstract
Background: Observational studies have linked pesticide exposure to various diseases, whereas organic food consumption has been associated with positive health outcomes. Organic farming standards prohibit the use of most pesticides, and organic food consumption may therefore reduce pesticide exposure., Objectives: To determine the effects of diet (Western compared with Mediterranean) and food type (conventional compared with organic) and sex on urinary pesticide residue excretion (UPRE), as well as associations between specific diet components and UPRE., Methods: In this 2-wk, randomized dietary intervention trial, healthy adults were randomly allocated to an intervention (n = 13) or conventional (n = 14) group. Whereas participants in the intervention group consumed a Mediterranean diet (MedDiet) made entirely from organic foods, the conventional group consumed a MedDiet made entirely from conventional foods. Both groups consumed habitual Western diets made from conventional foods before and after the 2-wk intervention period. The primary outcome was UPRE. In addition, we assessed diet composition and pesticide residue profiles in foods eaten. Participants were aware of group assignment, but the study assessors were not., Results: During the intervention period, total UPRE was 91% lower with organic (mean 17 μg/d; 95% CI: 15, 19) than with conventional (mean 180 μg/d; 95% CI: 153, 208) food consumption (P < 0.0001). In the conventional group, switching from the habitual Western diet to the MedDiet increased insecticide excretion from 7 to 25 μg/d (P < 0.0001), organophosphate excretion from 5 to 19 μg/d (P < 0.0001), and pyrethroid residue excretion from 2.0 to 4.5 μg/d (P < 0.0001). Small but significant effects of sex were detected for chlormequat, herbicide, and total pesticide residue excretion., Conclusions: Changing from a habitual Western diet to a MedDiet was associated with increased insecticide, organophosphate, and pyrethroid exposure, whereas organic food consumption reduced exposure to all groups of synthetic chemical pesticides. This may explain the positive health outcomes linked to organic food consumption in observational studies. This trial was registered at www.clinicaltrials.gov as NCT03254537., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.)
- Published
- 2022
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22. Disease Duration Influences Gene Expression in Neuromelanin-Positive Cells From Parkinson's Disease Patients.
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Tiklová K, Gillberg L, Volakakis N, Lundén-Miguel H, Dahl L, Serrano GE, Adler CH, Beach TG, and Perlmann T
- Abstract
Analyses of gene expression in cells affected by neurodegenerative disease can provide important insights into disease mechanisms and relevant stress response pathways. Major symptoms in Parkinson's disease (PD) are caused by the degeneration of midbrain dopamine (mDA) neurons within the substantia nigra. Here we isolated neuromelanin-positive dopamine neurons by laser capture microdissection from post-mortem human substantia nigra samples recovered at both early and advanced stages of PD. Neuromelanin-positive cells were also isolated from individuals with incidental Lewy body disease (ILBD) and from aged-matched controls. Isolated mDA neurons were subjected to genome-wide gene expression analysis by mRNA sequencing. The analysis identified hundreds of dysregulated genes in PD. Results showed that mostly non-overlapping genes were differentially expressed in ILBD, subjects who were early after diagnosis (less than five years) and those autopsied at more advanced stages of disease (over five years since diagnosis). The identity of differentially expressed genes suggested that more resilient, stably surviving DA neurons were enriched in samples from advanced stages of disease, either as a consequence of positive selection of a less vulnerable long-term surviving mDA neuron subtype or due to up-regulation of neuroprotective gene products., 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 © 2021 Tiklová, Gillberg, Volakakis, Lundén-Miguel, Dahl, Serrano, Adler, Beach and Perlmann.)
- Published
- 2021
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23. Effect of irrigation, fertiliser type and variety on grain yield and nutritional quality of spelt wheat (Triticum spelta) grown under semi-arid conditions.
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Wang J, Barański M, Hasanaliyeva G, Korkut R, Kalee HA, Leifert A, Winter S, Janovska D, Willson A, Barkla B, Iversen PO, Seal C, Bilsborrow P, Leifert C, Rempelos L, and Volakakis N
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- Agricultural Irrigation methods, Antioxidants analysis, Flour analysis, Greece, Manure, Micronutrients analysis, Minerals analysis, Species Specificity, Fertilizers, Nutritive Value, Triticum chemistry, Triticum growth & development
- Abstract
Previous studies reported higher antioxidant and mineral micronutrient concentrations in organic compared to conventional wheat flour, but the reasons are poorly understood. Here we report results from a long-term, factorial field experiment designed to assess effects of variety choice, supplementary irrigation and contrasting fertilization regimes used in organic and conventional production on the nutritional quality and yield of spelt wheat grown in a semi-arid environment. Long-straw (Oberkulmer, Rubiota, ZOR) varieties had 10-40% higher grain Cu, Fe, Mn and Zn concentrations, while the modern, short straw variety Filderstolz had 15-38% higher grain antioxidant activity. Supplementary irrigation and the use of manure instead of mineral NPK as fertilizer had no substantial effect on the nutritional composition of spelt grain, but increased grain yields by ~ 150 and ~ 18% respectively. Overall, this suggests that breeding/variety selection is the most promising approach to improve the nutritional quality of spelt grain in semi-arid production environments., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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24. Effect of Organic and Conventional Production Methods on Fruit Yield and Nutritional Quality Parameters in Three Traditional Cretan Grape Varieties: Results from a Farm Survey.
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Hasanaliyeva G, Chatzidimitrou E, Wang J, Baranski M, Volakakis N, Pakos P, Seal C, Rosa EAS, Markellou E, Iversen PO, Vigar V, Willson A, Barkla B, Leifert C, and Rempelos L
- Abstract
The antioxidants found in grapes and wine have been linked to health benefits in humans, but may be affected by agronomic parameters, grape type/variety, and processing. Here, we report results of a farm survey which investigated the effects of production system (organic vs. conventional) and grape variety on fruit yield, total antioxidant activity/capacity (TAA, assessed by the Trolox Equivalent Antioxidant Capacity (TEAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays), and total concentrations of total phenolics (TPC) and anthocyanins (TAC) in grapes of one red (Kotsifali) and two white (Villana and/or Vidiano) traditional Cretan grape varieties. Analysis of variance (ANOVA) results showed that grape variety choice had a more substantial effect on TPC, TAA, and TAC than primary production protocols, and significant interactions were identified between production system and grape variety choice for TAA
TEAC . Specifically, TAATEAC was significantly (57%) higher in organic than conventional Vidiano grapes, while there was no significant effect of production system on TAATEAC in Kotsifali and Villana grapes. As expected from previous studies, the TAC was substantially higher in red Kotsifali grapes. Redundancy analysis (RDA) identified grape variety as the only strong explanatory variable/driver for yield, TPC, TAA, and TAC of table grapes, and positive associations were detected between the variety Vidiano and both TPC and TAATEAC . All other explanatory variables included in the RDA (including supplementary irrigation, orchard orientation, production system, soil type, vineyard age, plant density, and fertiliser inputs) explained only a small proportion of the additional variation.- Published
- 2021
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25. Effects of Production Region, Production Systems and Grape Type/Variety on Nutritional Quality Parameters of Table Grapes; Results from a UK Retail Survey.
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Hasanaliyeva G, Chatzidimitrou E, Wang J, Baranski M, Volakakis N, Seal C, Rosa EAS, Iversen PO, Vigar V, Barkla B, Leifert C, and Rempelos L
- Abstract
Grapes contain high concentrations of secondary metabolites and antioxidants that have been linked to a reduction of several chronic diseases. Here, we report results of a UK retail survey, which investigated the effect of the production region (Mediterranean vs. South Africa), grape type (white vs. red vs. black) and variety, and production system (organic vs. conventional) on antioxidant activity and concentrations of phenolic compounds in table grapes. Black grapes had ~180% total antioxidant activity (TAA), ~60% higher total phenolic content (TPC) and ~40 times higher anthocyanin concentrations (TAC) than white grapes, while red grapes had intermediate levels of TAA, TPC and TAC. The effects of season and production system and differences between varieties of the same grape type were substantially smaller. Grapes imported from Mediterranean countries in summer had a 14% higher TPC and ~20% higher TAA than grapes imported from South Africa in winter, and organic grapes had a 16% higher TPC and 22% higher TAA, but ~30% lower TAC than conventional grapes. Significant differences in TPC, TAA and/or TAC between organic and conventional grapes could only be detected for specific grape types, varieties and/or sampling years.
- Published
- 2020
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26. Author Correction: Single cell transcriptomics identifies stem cell-derived graft composition in a model of Parkinson's disease.
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Tiklová K, Nolbrant S, Fiorenzano A, Björklund ÅK, Sharma Y, Heuer A, Gillberg L, Hoban DB, Cardoso T, Adler AF, Birtele M, Lundén-Miguel H, Volakakis N, Kirkeby A, Perlmann T, and Parmar M
- Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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- 2020
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27. Single cell transcriptomics identifies stem cell-derived graft composition in a model of Parkinson's disease.
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Tiklová K, Nolbrant S, Fiorenzano A, Björklund ÅK, Sharma Y, Heuer A, Gillberg L, Hoban DB, Cardoso T, Adler AF, Birtele M, Lundén-Miguel H, Volakakis N, Kirkeby A, Perlmann T, and Parmar M
- Subjects
- Animals, Brain metabolism, Cell Differentiation, Corpus Striatum, Disease Models, Animal, Dopamine metabolism, Embryonic Stem Cells cytology, Female, Graft Survival, Humans, Multigene Family, RNA-Seq, Rats, Rats, Nude, Regeneration, Single-Cell Analysis, Transcriptome, Dopaminergic Neurons cytology, Parkinson Disease therapy, Stem Cell Transplantation, Stem Cells cytology
- Abstract
Cell replacement is a long-standing and realistic goal for the treatment of Parkinson's disease (PD). Cells for transplantation can be obtained from fetal brain tissue or from stem cells. However, after transplantation, dopamine (DA) neurons are seen to be a minor component of grafts, and it has remained difficult to determine the identity of other cell types. Here, we report analysis by single-cell RNA sequencing (scRNA-seq) combined with comprehensive histological analyses to characterize intracerebral grafts from human embryonic stem cells (hESCs) and fetal tissue after functional maturation in a pre-clinical rat PD model. We show that neurons and astrocytes are major components in both fetal and stem cell-derived grafts. Additionally, we identify a cell type closely resembling a class of recently identified perivascular-like cells in stem cell-derived grafts. Thus, this study uncovers previously unknown cellular diversity in a clinically relevant cell replacement PD model.
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- 2020
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28. Single-cell RNA sequencing reveals midbrain dopamine neuron diversity emerging during mouse brain development.
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Tiklová K, Björklund ÅK, Lahti L, Fiorenzano A, Nolbrant S, Gillberg L, Volakakis N, Yokota C, Hilscher MM, Hauling T, Holmström F, Joodmardi E, Nilsson M, Parmar M, and Perlmann T
- Subjects
- Animals, Gene Expression Regulation, Developmental, Homeodomain Proteins metabolism, Mice, Transcription Factors metabolism, Brain cytology, Dopaminergic Neurons metabolism, Sequence Analysis, RNA methods
- Abstract
Midbrain dopamine (mDA) neurons constitute a heterogenous group of cells that have been intensely studied, not least because their degeneration causes major symptoms in Parkinson's disease. Understanding the diversity of mDA neurons - previously well characterized anatomically - requires a systematic molecular classification at the genome-wide gene expression level. Here, we use single cell RNA sequencing of isolated mouse neurons expressing the transcription factor Pitx3, a marker for mDA neurons. Analyses include cells isolated during development up until adulthood and the results are validated by histological characterization of newly identified markers. This identifies seven neuron subgroups divided in two major branches of developing Pitx3-expressing neurons. Five of them express dopaminergic markers, while two express glutamatergic and GABAergic markers, respectively. Analysis also indicate evolutionary conservation of diversity in humans. This comprehensive molecular characterization will provide a valuable resource for elucidating mDA neuron subgroup development and function in the mammalian brain.
- Published
- 2019
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29. Effects of Agronomic Management and Climate on Leaf Phenolic Profiles, Disease Severity, and Grain Yield in Organic and Conventional Wheat Production Systems.
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Rempelos L, Almuayrifi AM, Baranski M, Tetard-Jones C, Eyre M, Shotton P, Cakmak I, Ozturk L, Cooper J, Volakakis N, Schmidt C, Sufar E, Wang J, Wilkinson A, Rosa EAS, Zhao B, Rose TJ, Leifert C, and Bilsborrow P
- Subjects
- Ascomycota drug effects, Ascomycota physiology, Climate, Fertilizers analysis, Fungicides, Industrial pharmacology, Plant Diseases microbiology, Plant Diseases prevention & control, Plant Leaves chemistry, Plant Leaves drug effects, Plant Leaves growth & development, Plant Leaves microbiology, Seeds chemistry, Seeds drug effects, Seeds growth & development, Triticum growth & development, Triticum microbiology, Agriculture methods, Phenols analysis, Triticum chemistry, Triticum drug effects
- Abstract
Agricultural intensification over the last 40 years has increased cereal yields, but there is very limited information on the effects of intensification practices (e.g., nondiverse rotations, mineral NPK fertilizer, and pesticides) on crop health and quality. Results from the study reported here suggest that the use of mineral NPK fertilizers reduces phenolic acid and flavonoid concentrations in leaves and increases the susceptibility of wheat to lodging and powdery mildew, when compared to composted FYM inputs. In contrast, the use of herbicides, fungicides, and growth regulators reduces lodging and foliar disease severity but had no effect on phenolic acid and flavonoid concentrations. The use of composted FYM inputs also resulted in a significant grain yield reduction and not substantially reduced the severity of opportunistic pathogens such as Septoria, which remain a major yield limiting factor unless fungicides are used and/or more Septoria resistant varieties become available.
- Published
- 2018
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30. Real-World Data on Health-Related Quality of Life Assessment in Patients With Breast Cancer Receiving Subcutaneous Trastuzumab.
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Syrios J, Pappa E, Volakakis N, Grivas A, Alafis J, Manioudaki S, Tzouda V, Korogiannos A, Rapti C, Koufopoulos N, Nikolaidou A, Kanavou E, Alexopoulos A, and Koumarianou A
- Abstract
Purpose: Trastuzumab, a humanized anti-human epidermal growth factor receptor 2 (anti-HER2) antibody delivered intravenously, has revolutionized the treatment of patients with breast cancer overexpressing HER2 protein. Recently, a newer subcutaneous formulation was shown to have comparable efficacy to the initial intravenous trastuzumab. In this study, we aimed to evaluate the impact of subcutaneous trastuzumab on the health-related quality of life (HRQoL) of patients diagnosed with early or metastatic HER2-overexpressing breast cancer., Methods: Patients were provided with the EORTC QLQ-C30 (European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30) and the BR-23 questionnaires. The scoring of questionnaires and patient's sociodemographic and clinicopathologic characteristics were recorded and analyzed by descriptive and correlation statistics employing t test and 2-way analysis of variance., Results: A total of 163 patients agreed to participate in the study. About 90 of 163 patients (55.21%) received subcutaneous trastuzumab and 21 patients intravenous trastuzumab (12.88%). A control group of 52 HER2+ patients received chemotherapy without trastuzumab (31.90%). Patients receiving subcutaneous trastuzumab were older and of more advanced disease stage compared with those receiving chemotherapy (58.5 vs 51 years, 39.8% vs 28.8% advanced disease). In univariate analysis, subcutaneous trastuzumab was associated with less nausea and vomiting ( P = .002) but worse cognitive function ( P = .013) and dyspnea ( P = .042). Patients who have received >8 cycles of subcutaneous trastuzumab reported less diarrhea ( P = .049) and systemic therapy side effects ( P = .015). Multivariate analysis showed that patients without comorbidity receiving subcutaneous trastuzumab had less treatment side effects, less upset by hair loss, and higher emotional functioning. Of note, mastectomy and subcutaneous trastuzumab were associated with improved role functioning ( P = .021). In metastatic disease, no negative impact of subcutaneous trastuzumab on HRQoL was found., Conclusions: The administration of subcutaneous trastuzumab improved certain symptoms and did not adversely affect most of the assessed functional scales. Particularly, in the metastatic setting, subcutaneous trastuzumab had no negative impact on HRQoL., Competing Interests: Declaration of conflicting interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2018
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31. Single-Cell Analysis Reveals a Close Relationship between Differentiating Dopamine and Subthalamic Nucleus Neuronal Lineages.
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Kee N, Volakakis N, Kirkeby A, Dahl L, Storvall H, Nolbrant S, Lahti L, Björklund ÅK, Gillberg L, Joodmardi E, Sandberg R, Parmar M, and Perlmann T
- Subjects
- Biomarkers metabolism, Body Patterning genetics, Dopaminergic Neurons metabolism, Embryonic Stem Cells cytology, Embryonic Stem Cells metabolism, Gene Expression Profiling, Gene Regulatory Networks, Humans, Immunohistochemistry, LIM-Homeodomain Proteins metabolism, Neurogenesis genetics, Sequence Analysis, RNA, Signal Transduction genetics, Transcription Factors metabolism, Cell Differentiation genetics, Cell Lineage genetics, Dopaminergic Neurons cytology, Single-Cell Analysis methods, Subthalamic Nucleus cytology
- Abstract
Stem cell engineering and grafting of mesencephalic dopamine (mesDA) neurons is a promising strategy for brain repair in Parkinson's disease (PD). Refinement of differentiation protocols to optimize this approach will require deeper understanding of mesDA neuron development. Here, we studied this process using transcriptome-wide single-cell RNA sequencing of mouse neural progenitors expressing the mesDA neuron determinant Lmx1a. This approach resolved the differentiation of mesDA and neighboring neuronal lineages and revealed a remarkably close relationship between developing mesDA and subthalamic nucleus (STN) neurons, while also highlighting a distinct transcription factor set that can distinguish between them. While previous hESC mesDA differentiation protocols have relied on markers that are shared between the two lineages, we found that application of these highlighted markers can help to refine current stem cell engineering protocols, increasing the proportion of appropriately patterned mesDA progenitors. Our results, therefore, have important implications for cell replacement therapy in PD., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2017
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32. Nurr1 and Retinoid X Receptor Ligands Stimulate Ret Signaling in Dopamine Neurons and Can Alleviate α-Synuclein Disrupted Gene Expression.
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Volakakis N, Tiklova K, Decressac M, Papathanou M, Mattsson B, Gillberg L, Nobre A, Björklund A, and Perlmann T
- Subjects
- Animals, Bexarotene, Cells, Cultured, Dopaminergic Neurons drug effects, Embryo, Mammalian, Female, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Humans, Mesencephalon cytology, Mice, Mice, Transgenic, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Oxidopamine toxicity, Rats, Rats, Sprague-Dawley, Retinoid X Receptors agonists, Retinoid X Receptors genetics, Stereotyped Behavior physiology, Synapsins genetics, Synapsins metabolism, Tetrahydronaphthalenes pharmacology, Transcription Factors genetics, Transcription Factors metabolism, alpha-Synuclein genetics, Dopaminergic Neurons metabolism, Gene Expression Regulation genetics, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism, Retinoid X Receptors metabolism, Signal Transduction genetics, alpha-Synuclein metabolism
- Abstract
α-synuclein, a protein enriched in Lewy bodies and highly implicated in neurotoxicity in Parkinson's disease, is distributed both at nerve terminals and in the cell nucleus. Here we show that a nuclear derivative of α-synuclein induces more pronounced changes at the gene expression level in mouse primary dopamine (DA) neurons compared to a derivative that is excluded from the nucleus. Moreover, by RNA sequencing we analyzed the extent of genome-wide effects on gene expression resulting from expression of human α-synuclein in primary mouse DA neurons. The results implicated the transcription factor Nurr1 as a key dysregulated target of α-synuclein toxicity. Forced Nurr1 expression restored the expression of hundreds of dysregulated genes in primary DA neurons expressing α-synuclein, and therefore prompted us to test the possibility that Nurr1 can be pharmacologically targeted by bexarotene, a ligand for the retinoid X receptor that forms heterodimers with Nurr1. Although our data demonstrated that bexarotene was ineffective in neuroprotection in rats in vivo, the results revealed that bexarotene has the capacity to coregulate subsets of Nurr1 target genes including the receptor tyrosine kinase subunit Ret. Moreover, bexarotene was able to restore dysfunctional Ret-dependent neurotrophic signaling in α-synuclein-overexpressing mouse DA neurons. These data highlight the role of the Nurr1-Ret signaling pathway as a target of α-synuclein toxicity and suggest that retinoid X receptor ligands with appropriate pharmacological properties could have therapeutic potential in Parkinson's disease., Significance Statement: How α-synuclein, a protein enriched in Lewy bodies in Parkinson's disease, is causing neuropathology in dopamine neurons remains unclear. This study elucidated how α-synuclein is influencing gene expression and how Nurr1, a transcription factor known to protect dopamine neurons against α-synuclein toxicity, can counteract these effects. Moreover, given the protective role of Nurr1, this study also investigated how Nurr1 could be pharmacologically targeted via bexarotene, a ligand of Nurr1's heterodimerization partner retinoid X receptor (RXR). The results showed that RXR ligands could increase neurotrophic signaling, but provided a mixed picture of its potential in a Parkinson's disease rat model in vivo. However, this study clearly emphasized Nurr1's neuroprotective role and indicated that other RXR ligands could have therapeutic potential in Parkinson's disease., (Copyright © 2015 the authors 0270-6474/15/3514370-16$15.00/0.)
- Published
- 2015
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33. Dopaminergic control of autophagic-lysosomal function implicates Lmx1b in Parkinson's disease.
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Laguna A, Schintu N, Nobre A, Alvarsson A, Volakakis N, Jacobsen JK, Gómez-Galán M, Sopova E, Joodmardi E, Yoshitake T, Deng Q, Kehr J, Ericson J, Svenningsson P, Shupliakov O, and Perlmann T
- Subjects
- Animals, Behavior, Animal, Biogenic Monoamines metabolism, Cell Survival drug effects, Dopaminergic Neurons physiology, Humans, LIM-Homeodomain Proteins genetics, Mice, Mice, Knockout, Parkinson Disease genetics, Parkinson Disease psychology, Transcription Factors genetics, Transcription Factors physiology, Autophagy genetics, Dopamine metabolism, LIM-Homeodomain Proteins metabolism, Lysosomes metabolism, Parkinson Disease physiopathology, Transcription Factors metabolism
- Abstract
The role of developmental transcription factors in maintenance of neuronal properties and in disease remains poorly understood. Lmx1a and Lmx1b are key transcription factors required for the early specification of ventral midbrain dopamine (mDA) neurons. Here we show that conditional ablation of Lmx1a and Lmx1b after mDA neuron specification resulted in abnormalities that show striking resemblance to early cellular abnormalities seen in Parkinson's disease. We found that Lmx1b was required for the normal execution of the autophagic-lysosomal pathway and for the integrity of dopaminergic nerve terminals and long-term mDA neuronal survival. Notably, human LMX1B expression was decreased in mDA neurons in brain tissue affected by Parkinson's disease. Thus, these results reveal a sustained and essential requirement of Lmx1b for the function of midbrain mDA neurons and suggest that its dysfunction is associated with Parkinson's disease pathogenesis.
- Published
- 2015
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34. Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses.
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Barański M, Srednicka-Tober D, Volakakis N, Seal C, Sanderson R, Stewart GB, Benbrook C, Biavati B, Markellou E, Giotis C, Gromadzka-Ostrowska J, Rembiałkowska E, Skwarło-Sońta K, Tahvonen R, Janovská D, Niggli U, Nicot P, and Leifert C
- Subjects
- Crops, Agricultural chemistry, Flavonoids analysis, Humans, Hydroxybenzoates analysis, Nutritive Value, Organic Agriculture, Polyphenols analysis, Antioxidants analysis, Cadmium analysis, Food, Organic analysis, Pesticide Residues analysis
- Abstract
Demand for organic foods is partially driven by consumers' perceptions that they are more nutritious. However, scientific opinion is divided on whether there are significant nutritional differences between organic and non-organic foods, and two recent reviews have concluded that there are no differences. In the present study, we carried out meta-analyses based on 343 peer-reviewed publications that indicate statistically significant and meaningful differences in composition between organic and non-organic crops/crop-based foods. Most importantly, the concentrations of a range of antioxidants such as polyphenolics were found to be substantially higher in organic crops/crop-based foods, with those of phenolic acids, flavanones, stilbenes, flavones, flavonols and anthocyanins being an estimated 19 (95 % CI 5, 33) %, 69 (95 % CI 13, 125) %, 28 (95 % CI 12, 44) %, 26 (95 % CI 3, 48) %, 50 (95 % CI 28, 72) % and 51 (95 % CI 17, 86) % higher, respectively. Many of these compounds have previously been linked to a reduced risk of chronic diseases, including CVD and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies. Additionally, the frequency of occurrence of pesticide residues was found to be four times higher in conventional crops, which also contained significantly higher concentrations of the toxic metal Cd. Significant differences were also detected for some other (e.g. minerals and vitamins) compounds. There is evidence that higher antioxidant concentrations and lower Cd concentrations are linked to specific agronomic practices (e.g. non-use of mineral N and P fertilisers, respectively) prescribed in organic farming systems. In conclusion, organic crops, on average, have higher concentrations of antioxidants, lower concentrations of Cd and a lower incidence of pesticide residues than the non-organic comparators across regions and production seasons.
- Published
- 2014
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35. Sox6 and Otx2 control the specification of substantia nigra and ventral tegmental area dopamine neurons.
- Author
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Panman L, Papathanou M, Laguna A, Oosterveen T, Volakakis N, Acampora D, Kurtsdotter I, Yoshitake T, Kehr J, Joodmardi E, Muhr J, Simeone A, Ericson J, and Perlmann T
- Subjects
- Animals, Body Patterning, Humans, Mice, Transgenic, Organ Specificity, Substantia Nigra embryology, Substantia Nigra metabolism, Ventral Tegmental Area embryology, Ventral Tegmental Area metabolism, Dopaminergic Neurons physiology, Otx Transcription Factors physiology, SOXD Transcription Factors physiology, Substantia Nigra cytology, Ventral Tegmental Area cytology
- Abstract
Distinct midbrain dopamine (mDA) neuron subtypes are found in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA), but it is mainly SNc neurons that degenerate in Parkinson's disease. Interest in how mDA neurons develop has been stimulated by the potential use of stem cells in therapy or disease modeling. However, very little is known about how specific dopaminergic subtypes are generated. Here, we show that the expression profiles of the transcription factors Sox6, Otx2, and Nolz1 define subpopulations of mDA neurons already at the neural progenitor cell stage. After cell-cycle exit, Sox6 selectively localizes to SNc neurons, while Otx2 and Nolz1 are expressed in a subset of VTA neurons. Importantly, Sox6 ablation leads to decreased expression of SNc markers and a corresponding increase in VTA markers, while Otx2 ablation has the opposite effect. Moreover, deletion of Sox6 affects striatal innervation and dopamine levels. We also find reduced Sox6 levels in Parkinson's disease patients. These findings identify Sox6 as a determinant of SNc neuron development and should facilitate the engineering of relevant mDA neurons for cell therapy and disease modeling., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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36. Listeria monocytogenes-associated meningitis and arthritis in an immunocompetent 65-year-old woman: a case report.
- Author
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Anyfantakis D, Volakakis N, Kosmidou K, Polimili G, and Kastanakis S
- Subjects
- Aged, Arthritis microbiology, Female, Humans, Immunocompetence, Listeria monocytogenes isolation & purification, Listeriosis complications, Meningitis, Listeria cerebrospinal fluid, Meningitis, Listeria microbiology, Meropenem, Treatment Outcome, Anti-Bacterial Agents therapeutic use, Arthritis diagnosis, Arthritis drug therapy, Listeria monocytogenes pathogenicity, Meningitis, Listeria diagnosis, Meningitis, Listeria drug therapy, Thienamycins therapeutic use
- Abstract
We report an unusual case of concurrent meningitis and infectious monoarthritis due to Listeria monocytogenes in a 65-year-old woman presenting to our department with a transient gastrointestinal tract illness. During hospitalization the patient's neurological status deteriorated, presenting signs of meningeal irritation along with signs of inflammation and oedema of the right knee. Blood cultures and cultures of the cerebrospinal fluid and of the sinovial fluid aspirate showed growth of L. monocytogenes gram positive rods. The patient received a three-week course of intravenous meropenem with significant improvement. To the best of our knowledge this is the first case of concurrent listerial meningitis and arthritis in an immunocompetent patient. Despite the rarity of the disease in healthy individuals a high index of suspicion is required for unusual manifestations of listerial infections especially among high risk groups such as the elderly.
- Published
- 2014
37. NURR1 in Parkinson disease--from pathogenesis to therapeutic potential.
- Author
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Decressac M, Volakakis N, Björklund A, and Perlmann T
- Subjects
- Animals, Dopaminergic Neurons pathology, Humans, Mesencephalon pathology, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Parkinson Disease genetics, Parkinson Disease pathology, Dopaminergic Neurons metabolism, Mesencephalon metabolism, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism, Parkinson Disease metabolism
- Abstract
In Parkinson disease (PD), affected midbrain dopamine (DA) neurons lose specific dopaminergic properties before the neurons die. How the phenotype of DA neurons is normally established and the ways in which pathology affects the maintenance of cell identity are, therefore, important considerations. Orphan nuclear receptor NURR1 (NURR1, also known as NR4A2) is involved in the differentiation of midbrain DA neurons, but also has an important role in the adult brain. Emerging evidence indicates that impaired NURR1 function might contribute to the pathogenesis of PD: NURR1 and its transcriptional targets are downregulated in midbrain DA neurons that express high levels of the disease-causing protein α-synuclein. Clinical and experimental data indicate that disrupted NURR1 function contributes to induction of DA neuron dysfunction, which is seen in early stages of PD. The likely involvement of NURR1 in the development and progression of PD makes this protein a potentially interesting target for therapeutic intervention.
- Published
- 2013
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38. Transcription factor Nurr1 maintains fiber integrity and nuclear-encoded mitochondrial gene expression in dopamine neurons.
- Author
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Kadkhodaei B, Alvarsson A, Schintu N, Ramsköld D, Volakakis N, Joodmardi E, Yoshitake T, Kehr J, Decressac M, Björklund A, Sandberg R, Svenningsson P, and Perlmann T
- Subjects
- Animals, Behavior, Animal, Cell Nucleus genetics, Dopamine metabolism, Dopaminergic Neurons ultrastructure, Gene Expression, Genes, Mitochondrial, Mice, Mice, Knockout, Mice, Transgenic, Nuclear Receptor Subfamily 4, Group A, Member 2 deficiency, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Visual Cortex metabolism, Dopaminergic Neurons metabolism, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism
- Abstract
Developmental transcription factors important in early neuron specification and differentiation often remain expressed in the adult brain. However, how these transcription factors function to mantain appropriate neuronal identities in adult neurons and how transcription factor dysregulation may contribute to disease remain largely unknown. The transcription factor Nurr1 has been associated with Parkinson's disease and is essential for the development of ventral midbrain dopamine (DA) neurons. We used conditional Nurr1 gene-targeted mice in which Nurr1 is ablated selectively in mature DA neurons by treatment with tamoxifen. We show that Nurr1 ablation results in a progressive pathology associated with reduced striatal DA, impaired motor behaviors, and dystrophic axons and dendrites. We used laser-microdissected DA neurons for RNA extraction and next-generation mRNA sequencing to identify Nurr1-regulated genes. This analysis revealed that Nurr1 functions mainly in transcriptional activation to regulate a battery of genes expressed in DA neurons. Importantly, nuclear-encoded mitochondrial genes were identified as the major functional category of Nurr1-regulated target genes. These studies indicate that Nurr1 has a key function in sustaining high respiratory function in these cells, and that Nurr1 ablation in mice recapitulates early features of Parkinson's disease.
- Published
- 2013
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39. Essential role for DNA-PK-mediated phosphorylation of NR4A nuclear orphan receptors in DNA double-strand break repair.
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Malewicz M, Kadkhodaei B, Kee N, Volakakis N, Hellman U, Viktorsson K, Leung CY, Chen B, Lewensohn R, van Gent DC, Chen DJ, and Perlmann T
- Subjects
- Animals, Cell Line, Cells, Cultured, Gene Knockout Techniques, Humans, Mice, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Phosphorylation, Protein Transport, Severe Combined Immunodeficiency genetics, Severe Combined Immunodeficiency physiopathology, Calcium-Binding Proteins metabolism, DNA Breaks, Double-Stranded, DNA Repair, DNA-Activated Protein Kinase metabolism, DNA-Binding Proteins metabolism, Nuclear Proteins metabolism, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism
- Abstract
DNA-dependent protein kinase (DNA-PK) is a central regulator of DNA double-strand break (DSB) repair; however, the identity of relevant DNA-PK substrates has remained elusive. NR4A nuclear orphan receptors function as sequence-specific DNA-binding transcription factors that participate in adaptive and stress-related cell responses. We show here that NR4A proteins interact with the DNA-PK catalytic subunit and, upon exposure to DNA damage, translocate to DSB foci by a mechanism requiring the activity of poly(ADP-ribose) polymerase-1 (PARP-1). At DNA repair foci, NR4A is phosphorylated by DNA-PK and promotes DSB repair. Notably, NR4A transcriptional activity is entirely dispensable in this function, and core components of the DNA repair machinery are not transcriptionally regulated by NR4A. Instead, NR4A functions directly at DNA repair sites by a process that requires phosphorylation by DNA-PK. Furthermore, a severe combined immunodeficiency (SCID)-causing mutation in the human gene encoding the DNA-PK catalytic subunit impairs the interaction and phosphorylation of NR4A at DSBs. Thus, NR4As represent an entirely novel component of DNA damage response and are substrates of DNA-PK in the process of DSB repair.
- Published
- 2011
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40. Effect of organic and conventional crop rotation, fertilization, and crop protection practices on metal contents in wheat (Triticum aestivum).
- Author
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Cooper J, Sanderson R, Cakmak I, Ozturk L, Shotton P, Carmichael A, Haghighi RS, Tetard-Jones C, Volakakis N, Eyre M, and Leifert C
- Subjects
- Fertilization, Fertilizers analysis, Metals metabolism, Soil Pollutants analysis, Soil Pollutants metabolism, Triticum metabolism, Agriculture methods, Metals analysis, Triticum chemistry
- Abstract
The effects of organic versus conventional crop management practices (crop rotation, crop protection, and fertility management strategies) on wheat yields and grain metal (Al, Cd, Cu, Ni, Pb, and Zn) concentrations were investigated in a long-term field trial. The interactions between crop management practices and the season that the crop was grown were investigated using univariate and redundancy analysis approaches. Grain yields were highest where conventional fertility management and crop protection practices were used, but growing wheat after a previous crop of grass/clover was shown to partially compensate for yield reductions due to the use of organic fertility management. All metals except for Pb were significantly affected by crop management practices and the year that the wheat was grown. Grain Cd and Cu levels were higher on average when conventional fertility management practices were used. Al and Cu were higher on average when conventional crop protection practices were used. The results demonstrate that there is potential to manage metal concentrations in the diet by adopting specific crop management practices shown to affect crop uptake of metals.
- Published
- 2011
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41. NR4A orphan nuclear receptors as mediators of CREB-dependent neuroprotection.
- Author
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Volakakis N, Kadkhodaei B, Joodmardi E, Wallis K, Panman L, Silvaggi J, Spiegelman BM, and Perlmann T
- Subjects
- Animals, Cell Survival drug effects, Cells, Cultured, Cyclic AMP Response Element-Binding Protein genetics, Dose-Response Relationship, Drug, Embryonic Stem Cells cytology, Female, Gene Expression Profiling, Glutamic Acid pharmacology, Hippocampus cytology, Hippocampus drug effects, Hippocampus metabolism, Hydrogen Peroxide pharmacology, Ionomycin pharmacology, Kainic Acid pharmacology, Male, Mice, Mice, Knockout, Neurons cytology, Neuroprotective Agents metabolism, Nuclear Receptor Subfamily 4, Group A, Member 2 genetics, Oxidants pharmacology, Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha, RNA Interference, Reverse Transcriptase Polymerase Chain Reaction, Trans-Activators genetics, Trans-Activators metabolism, Transcription Factors, Cyclic AMP Response Element-Binding Protein metabolism, Embryonic Stem Cells metabolism, Neurons metabolism, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism
- Abstract
Induced expression of neuroprotective genes is essential for maintaining neuronal integrity after stressful insults to the brain. Here we show that NR4A nuclear orphan receptors are induced after excitotoxic and oxidative stress in neurons, up-regulate neuroprotective genes, and increase neuronal survival. Moreover, we show that NR4A proteins are induced by cAMP response element binding protein (CREB) in neurons exposed to stressful insults and that they function as mediators of CREB-induced neuronal survival. Animals with null mutations in three of six NR4A alleles show increased oxidative damage, blunted induction of neuroprotective genes, and increased vulnerability in the hippocampus after treatment with kainic acid. We also demonstrate that NR4A and the transcriptional coactivator PGC-1alpha independently regulate distinct CREB-dependent neuroprotective gene programs. These data identify NR4A nuclear orphan receptors as essential mediators of neuroprotection after exposure to neuropathological stress.
- Published
- 2010
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42. NR4A orphan nuclear receptors influence retinoic acid and docosahexaenoic acid signaling via up-regulation of fatty acid binding protein 5.
- Author
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Volakakis N, Joodmardi E, and Perlmann T
- Subjects
- Active Transport, Cell Nucleus, Cell Line, Humans, PPAR gamma metabolism, PPAR-beta metabolism, Promoter Regions, Genetic, Retinoid X Receptor alpha metabolism, Signal Transduction, Transcription, Genetic, Tretinoin pharmacology, Up-Regulation, Docosahexaenoic Acids metabolism, Fatty Acid-Binding Proteins genetics, Gene Expression Regulation, Nuclear Receptor Subfamily 4, Group A, Member 2 metabolism, Tretinoin metabolism
- Abstract
The orphan nuclear receptor (NR) Nurr1 is expressed in the developing and adult nervous system and is also induced as an immediate early gene in a variety of cell types. In silico analysis of human promoters identified fatty acid binding protein 5 (FABP5), a protein shown to enhance retinoic acid-mediated PPARbeta/delta signaling, as a potential Nurr1 target gene. Nurr1 has previously been implicated in retinoid signaling via its heterodimerization partner RXR. Since NRs are commonly involved in cross-regulatory control we decided to further investigate the regulatory relationship between Nurr1 and FABP5. FABP5 expression was up-regulated by Nurr1 and other NR4A NRs in HEK293 cells, and Nurr1 was shown to activate and bind to the FABP5 promoter, supporting that FABP5 is a direct downstream target of NR4A NRs. We also show that the RXR ligand docosahexaenoic acid (DHA) can induce nuclear translocation of FABP5. Moreover, via up-regulation of FABP5 Nurr1 can enhance retinoic acid-induced signaling of PPARbeta/delta and DHA-induced activation of RXR. We also found that other members of the NR4A orphan NRs can up-regulate FABP5. Thus, our findings suggest that NR4A orphan NRs can influence signaling events of other NRs via control of FABP5 expression levels.
- Published
- 2009
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43. Efficient production of mesencephalic dopamine neurons by Lmx1a expression in embryonic stem cells.
- Author
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Friling S, Andersson E, Thompson LH, Jönsson ME, Hebsgaard JB, Nanou E, Alekseenko Z, Marklund U, Kjellander S, Volakakis N, Hovatta O, El Manira A, Björklund A, Perlmann T, and Ericson J
- Subjects
- Animals, Embryonic Stem Cells cytology, Embryonic Stem Cells transplantation, Homeodomain Proteins genetics, Humans, LIM-Homeodomain Proteins, Mice, Parkinson Disease surgery, Rats, Rats, Sprague-Dawley, Transcription Factors, Dopamine metabolism, Embryonic Stem Cells physiology, Homeodomain Proteins biosynthesis, Mesencephalon cytology, Neurogenesis, Neurons cytology
- Abstract
Signaling factors involved in CNS development have been used to control the differentiation of embryonic stem cells (ESCs) into mesencephalic dopamine (mesDA) neurons, but tend to generate a limited yield of desired cell type. Here we show that forced expression of Lmx1a, a transcription factor functioning as a determinant of mesDA neurons during embryogenesis, effectively can promote the generation of mesDA neurons from mouse and human ESCs. Under permissive culture conditions, 75%-95% of mouse ESC-derived neurons express molecular and physiological properties characteristic of bona fide mesDA neurons. Similar to primary mesDA neurons, these cells integrate and innervate the striatum of 6-hydroxy dopamine lesioned neonatal rats. Thus, the enriched generation of functional mesDA neurons by forced expression of Lmx1a may be of future importance in cell replacement therapy of Parkinson disease.
- Published
- 2009
- Full Text
- View/download PDF
44. Characterization of the Nurr1 ligand-binding domain co-activator interaction surface.
- Author
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Volakakis N, Malewicz M, Kadkhodai B, Perlmann T, and Benoit G
- Subjects
- Binding Sites, Cells, Cultured, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Dimerization, Humans, Models, Molecular, Mutation, Nuclear Receptor Subfamily 4, Group A, Member 2, Organ Specificity, Protein Binding, Protein Denaturation physiology, Protein Structure, Tertiary, Receptors, Cytoplasmic and Nuclear metabolism, Retinoid X Receptors metabolism, Transcription Factors genetics, Transcription Factors metabolism, Transcriptional Activation, Transfection, Carrier Proteins metabolism, DNA-Binding Proteins chemistry, Ligands, Transcription Factors chemistry
- Abstract
The recently solved crystal structure of the orphan nuclear receptor (NR) Nurr1 ligand-binding domain (LBD) showed that Nurr1 lacks a cavity for ligand binding and a canonical NR co-activator-binding site. Computer modeling of the Nurr1 LBD structure identified a hydrophobic region on the surface of the Nurr1 LBD that was positioned on the opposite side from the classical co-activator-binding site. Site-directed mutagenesis demonstrated that this region is critical for the activity of the Nurr1 LBD. Most mutations introduced in this region reduced or abolished transcriptional activity of the Nurr1 LBD, but mutation at lysine (K577) resulted in a drastically increased activity. Moreover, the activity of the Nurr1 LBD was shown to correlate with a propensity for proteasome-dependent degradation revealing a close association between activity and Nurr1 protein turnover. These data provide novel insights into the mechanisms of transcription via the Nurr1 LBD and identify an alternative co-activator-binding surface that is unique to the NR4A family of NRs.
- Published
- 2006
- Full Text
- View/download PDF
45. Systemic Lipoplatin infusion results in preferential tumor uptake in human studies.
- Author
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Boulikas T, Stathopoulos GP, Volakakis N, and Vougiouka M
- Subjects
- Adipose Tissue metabolism, Antineoplastic Agents pharmacokinetics, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular metabolism, Cisplatin pharmacokinetics, Colonic Neoplasms drug therapy, Colonic Neoplasms metabolism, Digestive System Neoplasms pathology, Female, Humans, Infusions, Intravenous, Liver Neoplasms drug therapy, Liver Neoplasms metabolism, Liver Neoplasms secondary, Male, Middle Aged, Stomach Neoplasms drug therapy, Stomach Neoplasms metabolism, Stomach Neoplasms pathology, Antineoplastic Agents administration & dosage, Cisplatin administration & dosage, Digestive System Neoplasms drug therapy, Digestive System Neoplasms metabolism
- Abstract
Lipoplatin, a liposomal formulation of cisplatin, was developed with almost negligible nephrotoxicity, ototoxicity and neurotoxicity, as demonstrated in preclinical and Phase I human studies. A polyethylene-glycol coating of the liposome nanoparticles is supposed to result in tumor accumulation of the drug by extravasation through the altered tumor vasculature. We explored the hypothesis that intravenous infusion of Lipoplatin results in tumor targeting in four independent patient cases (one with hepatocellular adenocarcinoma, two with gastric cancer and one with colon cancer) who underwent Lipoplatin infusion followed by a prescheduled surgery approximately 20 h later. Direct measurement of the platinum levels in specimens from the excised tumors and normal tissues showed that the total platinum levels were on average 10-50 times higher in malignant tissue compared to the adjacent normal tissue specimens; most effective targeting was observed in colon cancer, with an accumulation up to 200-fold higher in colon tumors compared to normal colon tissue. Of the several surgical specimens, gastric tumors displayed the highest levels of total platinum suggesting Lipoplatin as a candidate anticancer agent for gastric tumors; gastric tumor specimens had up to 260 micrograms platinum /g tissue, that was higher than any tissue level in animals treated at much higher doses. Fat tissue displayed a high accumulation of total platinum in surgical specimens in three different patients, correlating to the lipid capsule of cisplatin in its Lipoplatin formulation. It was also inferred that normal tissue had more platinum trapped in the tissue but not reacted with macromolecules, whereas tumor tissue displayed platinum that reacted with cellular macromolecules; the data were consistent with a model where Lipoplatin damages more tumor compared to normal cells. In conclusion, Lipoplatin has the ability to preferentially concentrate in malignant tissue both of primary and metastatic origin following intravenous infusion to patients. In this respect, Lipoplatin emerges as a very promising drug in the arsenal of chemotherapeutics.
- Published
- 2005
46. Description and molecular analysis of SRY and AR genes in a patient with 46,XY pure gonadal dysgenesis (Swyer syndrome).
- Author
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Iliopoulos D, Volakakis N, Tsiga A, Rousso I, and Voyiatzis N
- Subjects
- Adolescent, Female, Humans, Chromosome Aberrations, Genes, sry, Gonadal Dysgenesis, 46,XY genetics, Mosaicism, Receptors, Androgen genetics
- Abstract
46,XY pure gonadal dysgenesis, first described in 1955 by Swyer, results from testicular tissue loss during the first 8 weeks of fetal life, a critical period for male differentiation. We describe a case of an 18 years old patient presented to us with a chief complain of primary amenorrhea. Chromosomal analysis revealed a 46,XY karyotype. A molecular investigation was undertaken in an attempt to determine mutations in SRY and AR genes through DNA sequencing. Mutations were shown to be absent. The molecular basis of Swyer syndrome is still unknown, although the presence of mutations in testicular organizing genes downstream of SRY is still to rule out. The patient, who is considered as female, was placed on estrogen replacement therapy, while bilateral prophylactic laparoscopic gonadectomy was programmed due to the high prevalence of gonadal tumors in this syndrome. No signs of malignance were detected in the gonadal tissue, which predicts that an intact SRY gene is usually, but not always, not related to the formation of malignancies like dysgeminomas or gonadoblastomas.
- Published
- 2004
- Full Text
- View/download PDF
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