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1. Pre- and Postnatal Dietary Exposure to a Pesticide Cocktail Disrupts Ovarian Functions in 8-Week-Old Female Mice

Author

Léonie Dopavogui, Florence Cadoret, Gaspard Loison, Sara El Fouikar, François-Xavier Frenois, Frank Giton, Sandrine Ellero-Simatos, Frédéric Lasserre, Arnaud Polizzi, Clémence Rives, Nicolas Loiseau, Roger D. Léandri, Nicolas Gatimel, Laurence Gamet-Payrastre, Toxicologie Intégrative & Métabolisme (ToxAlim-TIM), ToxAlim (ToxAlim), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Vétérinaire de Toulouse (ENVT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Ecole d'Ingénieurs de Purpan (INPT - EI Purpan), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), CHU Toulouse [Toulouse], Développement Embryonnaire, Fertilité et Environnement (DEFE), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Exposition, Perturbation Endocrino-métabolique et Reproduction (ToxAlim-EXPER), Institut Universitaire du Cancer de Toulouse - Oncopole (IUCT Oncopole - UMR 1037), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), L.D. was supported by a Ph.D. grant from INRAE (Animal Health Department). This work was supported by a grant from the Ministry for Agriculture and Food and the Ministry for an Ecological and Solidary Transition, with the financial support of the French Biodiversity Agency (GepeTho), by ANR France (Syneract), and by Région Occitanie. This work also received funding from Agence de la Biomédecine (AOR 2019).This paper benefited from the Imag’IN Platform of the Institut Universitaire du Cancer from April 2019 to August 2021 https://www.imagin-labs.net/imagin_v2/index.php? lang=EN (last accessed on 5 June 2022). We thank X. Blanc from INRAe SAAJ (Jouy-en-Josas) for his technical support for pellet preparation., ANR-18-CE34-0009,SYNERACT,Activation synergique de recepteurs nucléaires(2018), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)-Institut National de la Santé et de la Recherche Médicale (INSERM), LESUR, Hélène, and APPEL À PROJETS GÉNÉRIQUE 2018 - Activation synergique de recepteurs nucléaires - - SYNERACT2018 - ANR-18-CE34-0009 - AAPG2018 - VALID

Subjects
pesticide, folliculogenesis, ovary, endocrine disruption, progesterone, [SDV]Life Sciences [q-bio], Organic Chemistry, Pesticide Residues, General Medicine, Catalysis, Computer Science Applications, [SDV] Life Sciences [q-bio], Inorganic Chemistry, Dietary Exposure, Mice, Fruit, Animals, Female, Chlorpyrifos, Physical and Theoretical Chemistry, Pesticides, Molecular Biology, Spectroscopy
Abstract

International audience; Female infertility has a multifactorial origin, and exposure to contaminants, including pesticides, with endocrine-disrupting properties is considered to be involved in this reproductive disorder, especially when it occurs during early life. Pesticides are present in various facets of the environment, and consumers are exposed to a combination of multiple pesticide residues through food intake. The consequences of such exposure with respect to female fertility are not well known. Therefore, we aimed to assess the impact of pre- and postnatal dietary exposure to a pesticide mixture on folliculogenesis, a crucial process in female reproduction. Mice were exposed to the acceptable daily intake levels of six pesticides in a mixture (boscalid, captan, chlorpyrifos, thiacloprid, thiophanate and ziram) from foetal development until 8 weeks old. Female offspring presented with decreased body weight at weaning, which was maintained at 8 weeks old. This was accompanied by an abnormal ovarian ultrastructure, a drastic decrease in the number of corpora lutea and progesterone levels and an increase in ovary cell proliferation. In conclusion, this study shows that this pesticide mixture that can be commonly found in fruits in Europe, causing endocrine disruption in female mice with pre- and postnatal exposure by disturbing folliculogenesis, mainly in the luteinisation process.

Published
2022
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2. Cationic Biphotonic Lanthanide Luminescent Bioprobes Based on Functionalized Cross-Bridged Cyclam Macrocycles

Author

Amandine Roux, Damien Curton, Maryline Beyler, Raphaël Tripier, Véronique Patinec, Anh Thy Bui, Sophie Brasselet, Olivier Maury, Jean-Christophe Mulatier, Alexei Grichine, Jonathan Mendy, Chantal Andraud, François Riobé, Alain Duperray, Boris Le Guennic, Yannick Guyot, RENARD, NICOLAS, Chimie, Electrochimie Moléculaires et Chimie Analytique (CEMCA), Université de Brest (UBO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO), Laboratoire de Chimie - UMR5182 (LC), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute for Advanced Biosciences / Institut pour l'Avancée des Biosciences (Grenoble) (IAB), Centre Hospitalier Universitaire [Grenoble] (CHU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Etablissement français du sang - Auvergne-Rhône-Alpes (EFS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Luminescence (LUMINESCENCE), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), MOSAIC (MOSAIC), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), The authors are grateful to the referees for careful reading of the paper and valuable suggestions and comments. The authors also acknowledge support of the Ministère de l'Enseignement Supérieur et de la Recherche, the Centre National de la Recherche Scientifique, the Institut National de la Santé et de la Recherche Médicale and the Agence Nationale de la Recherche (SADAM ANR‐16‐CE07‐0015‐02). M.B. and R.T. thanks the ‘‘Service Commun de RMN’’ of the University of Brest. Confocal and 2P facility of the IAB platform was co‐funded thanks to grants of 'Association pour la Recherche sur le Cancer' (ARC, Villejuif, France), 'Ligue vs Cancer' (LCC Isère/Ardèche) and the CPER program. B.L.G. thanks the French GENCI‐CINES center for high‐performance computing resources., Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Université de Lyon-Université de Lyon, Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and ANR-16-CE07-0015,SADAM,Diagnostiquer et guérir par des agents azamacrocycliques multimodaux(2016)

Subjects
Lanthanide, Ytterbium, Macrocyclic Compounds, Luminescence, chemistry.chemical_element, 02 engineering and technology, Europium(III), 010402 general chemistry, Photochemistry, 01 natural sciences, Lanthanoid Series Elements, chemistry.chemical_compound, Coordination Complexes, Cations, Cell Line, Tumor, Cyclam, [CHIM] Chemical Sciences, Humans, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Ytterbium(III), Two-photon microscopy, Density Functional Theory, Photons, Aqueous solution, Luminescent Agents, Spectroscopy, Near-Infrared, Molecular Structure, Chemistry, Optical Imaging, Cationic polymerization, Bioprobe, [CHIM.COOR] Chemical Sciences/Coordination chemistry, 021001 nanoscience & nanotechnology, Bioimaging, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Solvent, 0210 nano-technology, Europium
Abstract

Cationic lanthanide complexes are generally able to spontaneously internalize into living cells. Following our previous works based on diMe-cyclen framework, a second generation of cationic water-soluble lanthanide complexes based on a constrained cross-bridged cyclam macrocycle functionalized with donor-p-conjugated picolinate antennas has been prepared with europium(III) and ytterbium(III). Their spectroscopic properties were thoroughly investigated in various solvents and rationalized with the help of DFT calculations. A significant improvement is observed in the case of the Eu3+ complex, while the Yb3+ analogous conserve an excellent brightness in aqueous solvent. Two-photon (2P) microscopy imaging experiments on living T24 human cancer cells confirmed the spontaneous internalization of the probes and images with good signal-to-noise have been obtained in the classical NIR-to-visible configuration with Eu3+ luminescent bioprobe and in the NIR-to-NIR with the Yb3+ one.

Published
2020

3. Процеси трансформації енергії в активованих йонами Er3+ лазерних матеріалах (огляд)

Author

A. H. Kevshyn, V. V. Halyan, T. A. Semenyuk, This paper support by national project MES of Ukraine (State registration number 0115U002348), and Робота виконана за підтримки держбюджетної теми МОН України (державний реєстраційний номер 0115U002348).

Subjects
Materials science, Physics::Optics, General Materials Science, Physical and Theoretical Chemistry, Condensed Matter Physics, lcsh:Physics, lcsh:QC1-999
Abstract

In the paper the features of energy transformation processes in activated with erbium ions laser materials were discussed based on optical transitions in 4f shell of Er3+ ion. Methods of excitation of the luminescence inchalcogenide glasses doped with Er3+ ions were described and found how its intensity depends on concentrationof the ions. Up-conversion and cross-relaxation play an important role in the transformation of excitations in erbium doped materials. In cross-relaxation the energy of one center can be nonradiatively transferred to another centeror divided between the two centers, while in the up-conversion, however, energy of several centers summed up inone center, bringing it acts as an additional channel of luminescence quenching, or as a way of pumping of thehigher energy levels.To improve the efficiency of optical excitation of many laser materials doped with erbium ions thesensitization with ytterbium ions that have intense absorption band in the range of ~(0.9-1)μm with "effective"width of about 1000 cm-1 as well a channel of the efficient nonradiative excitation energy transfer to Er3+ ions iswidely used. Scheme of energy transfer from Yb3+ ion to Er3+ ion was discussed and necessary conditions foreffective settlement of the upper laser level 4I13/2 of Er3+ ions in the ytterbium-erbium laser medium wereclarified.Keywords: lasermaterials, rareearthelements, up-conversion, cross-relaxation., В статті проведений аналіз різних літературних джерел, в яких описані основні процеси трансформації енергії в активованих йонами Er3+ лазерних матеріалах. Встановлено, що в основі цих процесів лежать ап-конверсійні та крос-релаксаційні переходи, які дають можливість реалізувати генерацію в ербієвих лазерах. Ефективним сенсибілізатором для йонів ербію є йони ітербію, які за рахунок безвипромінювального перенесення збудження ефективно передеють енергію йонам Er3+.

Published
2016

4. Tumour heterogeneity: the key advantages of single-cell analysis

Author

Francois Lamoureux, Marta Tellez-Gabriel, Benjamin Ory, Dominique Heymann, Marie-Françoise Heymann, Laboratorio Hematologia Oncologica y de Transplantes [Barcelona, Spain], Institut Investigacions Biomèdiques (IBB) Sant Pau [Barcelona, Spain]-Hospital de la Santa Creu i Sant Pau, Equipe LIGUE Nationale Contre le Cancer 2012, Physiopathologie des Adaptations Nutritionnelles (PhAN), Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Department of Oncology and Metabolism [Sheffield, UK], The University of Sheffield [Sheffield, U.K.], European Associated Laboratory [Sheffield, UK] (Sarcoma Research Unit), This paper was written as a part of a research project which received funding from the Seventh Framework Programme ([FP7/2007-2013]) under grant agreement n 264817—BONE-NET. This work was supported by the Bone Cancer Research Trust (UK, research project number 144681)., European Project: 264817,EC:FP7:PEOPLE,FP7-PEOPLE-2010-ITN,BONE-NET(2011), Heymann, Dominique, and European Training Network on Cancer-Induced Bone Diseases - BONE-NET - - EC:FP7:PEOPLE2011-02-01 - 2015-01-31 - 264817 - VALID

Subjects
0301 basic medicine, Tumour heterogeneity, circulating tumour cells, [SDV.CAN]Life Sciences [q-bio]/Cancer, Disease, Review, Biology, Bioinformatics, Catalysis, lcsh:Chemistry, Inorganic Chemistry, 03 medical and health sciences, Genetic Heterogeneity, [SDV.MHEP.PED] Life Sciences [q-bio]/Human health and pathology/Pediatrics, Single-cell analysis, [SDV.CAN] Life Sciences [q-bio]/Cancer, single cells, Neoplasms, Gene expression, Biopsy, medicine, Humans, Epigenetics, Physical and Theoretical Chemistry, Neoplasm Metastasis, lcsh:QH301-705.5, Molecular Biology, Spectroscopy, [SDV.MHEP.EM] Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism, [SDV.MHEP.RSOA] Life Sciences [q-bio]/Human health and pathology/Rhumatology and musculoskeletal system, [SDV.MHEP.PED]Life Sciences [q-bio]/Human health and pathology/Pediatrics, medicine.diagnostic_test, Organic Chemistry, General Medicine, [SDV.MHEP.EM]Life Sciences [q-bio]/Human health and pathology/Endocrinology and metabolism, Neoplastic Cells, Circulating, Phenotype, 3. Good health, Computer Science Applications, 030104 developmental biology, lcsh:Biology (General), lcsh:QD1-999, [SDV.MHEP.RSOA]Life Sciences [q-bio]/Human health and pathology/Rhumatology and musculoskeletal system, Cancer cell, Cancer research, Single-Cell Analysis, heterogeneity
Abstract

International audience; Tumour heterogeneity refers to the fact that different tumour cells can show distinct morphological and phenotypic profiles, including cellular morphology, gene expression, metabolism, motility, proliferation, and metastatic potential. This phenomenon occurs both between tumours (inter-tumour heterogeneity) and within tumours (intra-tumour heterogeneity), and it is caused by genetic and non-genetic factors. The heterogeneity of cancer cells introduces significant challenges in using molecular prognostic markers as well as for classifying patients that might benefit from specific therapies. Thus, research efforts for characterizing heterogeneity would be useful for a better understanding of the causes and progression of disease. It has been suggested that the study of heterogeneity within Circulating Tumour Cells (CTCs) could also reflect the full spectrum of mutations of the disease more accurately than a single biopsy of a primary or metastatic tumour. In the last years many high throughput methodologies have raised for the study of heterogeneity at different levels (i.e.: RNA, DNA, protein, epigenetic events). The aim of the current review is to stress clinical implications of tumour heterogeneity, as well as current available methodologies for their study with a specific attention to those able to assess heterogeneity at the single cell level.

Published
2016

5. Narrow Linewidth Excitonic Emission in Organic-Inorganic Lead Iodide Perovskite Single Crystals

Author

Diab, Hiba, Trippé-Allard, Gaëlle, Lédée, Ferdinand, Jemli, Khaoula, Vilar, Christèle, Bouchez, Guillaume, Jacques, Vincent L.R., Tejeda, Antonio, Even, Jacky, Lauret, Jean-Sébastien, Deleporte, Emmanuelle, Garrot, Damien, Laboratoire Aimé Cotton (LAC), École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Groupe d'Etude de la Matière Condensée (GEMAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes (UR)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photonique Quantique et Moléculaire (LPQM), École normale supérieure - Cachan (ENS Cachan)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), This work has received funding from the European Union’s Horizon 2020 research and innovation programme under the grant agreement No 687008. The information and views set out in this paper are those of the author(s) and do not necessarily reflect the official opinion of the European Union. Neither the European Union institutions and bodies nor any person acting on their behalf may be held responsible for the use which may be made of the information contained herein. J.S. Lauret is ajunior member of the Institut Universitaire de France., Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École normale supérieure - Cachan (ENS Cachan), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Photoluminescence, Exciton, 02 engineering and technology, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Laser linewidth, Condensed Matter::Materials Science, Condensed Matter::Superconductivity, General Materials Science, Physical and Theoretical Chemistry, Thin film, Spectroscopy, Perovskite (structure), business.industry, Condensed Matter::Other, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Full width at half maximum, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Crystallite, 0210 nano-technology, business
Abstract

International audience; Hybrid perovskite thin films have demonstrated impressive performance for solar energy conversion and optoelectronic applications. However, further progress will benefit from a better knowledge of the intrinsic photophysics of materials. Here, the temperature-dependent emission properties of CH3NH3PbI3 single crystals are investigated and compared to those of thin polycrystalline films by means of steady-state and time-resolved photoluminescence spectroscopy. Single crystals photoluminescence present a sharp excitonic emission at high energy, with full width at half maximum of only 5 meV, assigned to free excitonic recombination. We highlight a strong thermal broadening of the free excitonic emission, due to exciton–LO-phonon coupling. The emission turned to be very short-lived with a subnanosecond dynamics, mainly induced by the fast trapping of the excitons. The free excitonic emission is completely absent of the thin film spectra, which are dominated by trap state bands.

Published
2016

6. Homogeniczność grup fokusowych drogą do sukcesu w badaniach? Szkic metodologiczny z badań terenowych

Author

Wojciech Woźniak, Katedra Socjologii Ogólnej, Wydział Ekonomiczno-Socjologiczny, Uniwersytet Łódzki, and Wojciech Woźniak holds a PhD in sociology and works as an Assistant Professor in the Department of General Sociology, Faculty of Economics and Sociology, University of Lodz. His research interests cover: social inequalities, analysis of public discourse concerning social problems, Finish socio-economic model, and sociology of sport. He has authored a book Social Inequalities in Polish Political Discourse (Scholar, 2012) and more than 40 papers in scientific journals and collections.

Subjects
grupy fokusowe, homogeniczność, Methodology of Qualitative Research, Colloid and Surface Chemistry, metodologia badań jakościowych, dobór próby, Homogeneity, Group Interviewing, Physical and Theoretical Chemistry, Focus Groups, Sampling, wywiady grupowe
Abstract

The paper approaches the topic of sampling in the qualitative research design. Particular attention is paid to the composition of the focus groups in two important aspects: the homogeneity of the participants in terms of their positions in socio-occupational hierarchy and the pre-existing relations among the participants in the single group. The later issue is closely and directly intertwined with the former, in the case when the informants are approached in their institutional seting, and the research is conducted in a relatively small community. These problems are discussed in reference to the body of available methodological studies. The example of the research undertaken in aforementioned circumstances is subsequently presented to advocate the homogeneous composition of the focus groups while reconstructing the collective viewpoints of representatives of a particular level of public administrations. Avoidance of power relations within the groups proved profitable and effective. Substantial diferences between the groups were easily identifiable in spite of the pre-existing relations among participants, which were unavoidable in this very case. Artykuł podejmuje temat doboru próby podczas projektowania badań jakościowych. Szczególną uwagę zwraca się tu na kompozycję grup fokusowych ze względu na dwa ważne aspekty: ich homogeniczność pod względem pozycji badanych w społeczno-zawodowej hierarchii oraz wcześniejszych wzajemnych relacji pomiędzy uczestnikami jednej grupy. Ta druga kwestia wiąże się blisko i bezpośrednio z pierwszą w sytuacji, gdy uczestnicy fokusów objęci są analizą w swoim otoczeniu instytucjonalnym, a badanie prowadzone jest w relatywnie małej społeczności lokalnej. Te zagadnienia omówione są w odniesieniu do dostępnej literatury metodologicznej. Następnie zaprezentowany jest przykład badania przeprowadzonego w wyżej wymienionych okolicznościach, by wskazać zalety homogenicznej kompozycji grup fokusowych podczas rekonstruowania zbiorowych postaw przedstawicieli poszczególnych szczebli administracji publicznej. Uniknięcie relacji władz i podległości okazało się owocne i skuteczne. Zasadnicze różnice pomiędzy grupami było łatwo zidentyikować, mimo że w przypadku tego badania nie do uniknięcia była wcześniejsza znajomość uczestników przed rozpoczęciem sesji.

Published
2014