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61.
Paterson L Papagiakoumou E Milne G Garcés-Chávez V Briscoe T Sibbett W Dholakia K Riches AC 《Journal of biomedical optics》2007,12(5):054017
A passive, optical cell sorter is created using the light pattern of a 'nondiffracting' beam-the Bessel beam. As a precursor to cell sorting studies, microspheres are used to test the resolution of the sorter on the basis of particle size and refractive index. Variations in size and, more noticeably, refractive index, lead to a marked difference in the migration time of spheres in the Bessel beam. Intrinsic differences (size, refractive index) between native (unlabeled) cell populations are utilized for cell sorting. The large difference in size between erythrocytes and lymphocytes results in their successful separation in this beam pattern. The intrinsic differences in size and refractive index of other cells in the study (HL60 human promyelocytic leukaemic cells, murine bone marrow, and murine stem/progenitor cells) are not large enough to induce passive optical separation. Silica microsphere tags are attached to cells of interest to modify their size and refractive index, resulting in the separation of labeled cells. Cells collected after separation are viable, as evidenced by trypan blue dye exclusion, their ability to clone in vitro, continued growth in culture, and lack of expression of Caspase 3, a marker of apoptosis. 相似文献
62.
Meletios A Dimopoulos Evangelos Terpos Mario Boccadoro Sosana Delimpasi Meral Beksac Eirini Katodritou Philippe Moreau Luca Baldini Argiris Symeonidis Jelena Bila Albert Oriol Maria-Victoria Mateos Hermann Einsele Ioannis Orfanidis Tahamtan Ahmadi Jon Ukropec Tobias Kampfenkel Jordan M Schecter Sonja Zweegman 《The lancet oncology》2021,22(6):801-812
63.
Bonnie L. Breining Trisha Lala Macarena Martínez Cuitiño Facundo Manes Eleni Peristeri Kyrana Tsapkini 《Aphasiology》2015,29(4):488-505
Background: A cross-culturally valid nonverbal assessment of semantic knowledge is needed. Accurately identifying impairment of object semantics is important for diagnosis of several disorders, including distinguishing semantic variant primary progressive aphasia (svPPA), a neurodegenerative condition characterised by progressive impairment in word comprehension, from logopenic and nonfluent agrammatic variants, which are not associated with impaired object semantics. However, current assessments require culturally specific knowledge.Aims: We developed a cross-culturally valid short form of the Pyramids and Palm Trees Test to assess object semantic memory. We investigated its clinical utility in differentiating the semantic variant of primary progressive aphasia, from the logopenic and nonfluent agrammatic variants. Areas of atrophy associated with poor performance were identified.Methods & Procedures: Fourteen items that rely on knowledge of objects’ defining features were selected from the original 52-item version. The full and short forms were administered to healthy individuals in the US (N = 18), Argentina (N = 20), and Greece (N = 12) and performance was compared. Seventy-eight individuals with primary progressive aphasia in the US completed the short form. Behavioural performance of the svPPA group (N = 24) was compared to other variants. Atlas-based analysis identified regions where atrophy correlated with poor performance in 39 individuals with primary progressive aphasia who had high-resolution magnetic resonance imaging (MRI) scans.Outcomes & Results: Control performance was classified as normal on the short form significantly more often than on the full version. Across groups with primary progressive aphasia, the group with semantic variant performed significantly worse than the groups with logopenic or nonfluent agrammatic variants. Volume in left anterior and inferior temporal cortex correlated with performance.Conclusions: The short-form Pyramids and Palm Trees Test is a clinically relevant, cross-culturally valid assessment of nonverbal object semantics. It can be used to identify semantic impairments, with poor performance associated with atrophy of the temporal lobes. 相似文献
64.
Lymph nodes play a central role in the development of adaptive immunity against pathogens and particularly the generation of antigen-specific B cell responses in specialized areas called germinal centers (GCs). Lymph node (LN) pathology was recognized as an important consequence of human immunodeficiency virus (HIV) infection since the beginning of the HIV epidemic. Investigation into the structural and functional alterations induced by HIV and Simian immunodeficiency virus (SIV) has further cemented the central role that lymphoid tissue plays in HIV/SIV pathogenesis. The coexistence of constant local inflammation, altered tissue architecture, and relative exclusion of virus-specific CD8 T cells from the GCs creates a unique environment for the virus evolution and establishment of viral reservoir in specific GC cells, namely T follicular helper CD4 T cells (Tfh). A better understanding of the biology of immune cells in HIV-infected lymph nodes is a prerequisite to attaining the ultimate goal of complete viral eradication. 相似文献
65.
66.
Nikolaos Spantideas Eirini Drosou Anastasia Bougea Dimitrios Assimakopoulos 《BMC ear, nose, and throat disorders》2015,15(1):1-10
Gait function may be impaired in patients with vestibular disorders, making gait assessment in the clinical setting relevant for this patient population. The purpose of this study was to evaluate the discriminant validity of a gait assessment protocol between patients with vestibular disorders and healthy participants. Furthermore, test re-test reproducibility and the measurement error of gait performance measures in patients with vestibular lesions was performed under different walking conditions. Gait parameters of thirty-five patients with vestibular disorders and twenty-seven healthy controls were assessed twice with the GAITRite® system. Discriminant validity, reproducibility (intra class correlation [ICC]) and the measurement error (standard error of measurement [SEM], smallest detectable change [SDC]) were determined for gait speed, cadence and step length. Bland-Altman plots were made to assess systematic bias between tests. A significant effect of grouping on gait performance indicates discriminant validity of gait assessment. All tests revealed differences between patients and healthy controls (p < 0.01). The ICCs for test re-test reproducibility were excellent (0.70-0.96) and measurement error showed acceptable SDC values for gait parameters derived from three walking conditions (9-19 %). Bland-Altman plots indicated no systematic bias. Good validity and reproducibility of GAITRite® system measurements suggest that this system could facilitate the study of gait in patients with vestibular disorders in clinical settings. The SDC values for gait are generally small enough to detect changes after a rehabilitation program for patients with vestibular disorders. 相似文献
67.
Eirini Athanasiadou Maria Paschalidou Anna Theocharidou Nikolaos Kontoudakis Konstantinos Arapostathis Athina Bakopoulou 《Dental materials》2018,34(12):1797-1813
Objective
To investigate the biological interactions of a calcium silicate based cement (Biodentine?) with Stem Cells from Human Exfoliated Deciduous teeth (SHED), focusing on viability/proliferation, odontogenic differentiation, biomineralization and elemental release/exchange.Methods
Biodentine? specimens were used directly or for eluate preparation at serial dilutions (1:1–1:64). SHED cultures were established from deciduous teeth of healthy children. Viability/proliferation and morphological characteristics were evaluated by live/dead fluorescent staining, MTT assay and Scanning Electron Microscopy. Odontogenic differentiation by qRT-PCR, biomineralization by Alizarin red S staining, while ion elution by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES).Results
SHED effectively attached within the crystalline surface of Biodentine? specimens acquiring a spindle-shaped phenotype. Statistically significant stimulation of cell proliferation was induced at day 3 by eluates in dilutions from 1:16 to 1:64. Differential, concentration- and time-dependent expression patterns of odontogenic genes were observed under non-inductive and inductive (osteogenic) conditions, with significant up-regulation of DSPP and Runx2 at higher dilutions and a peak in expression of BMP-2, BGLAP and MSX-2 at 1:8 dilution on day 7. Progressive increase in mineralized tissue formation was observed with increasing dilutions of Biodentine? eluates. ICP-OES indicated that Biodentine? absorbed Ca, Mg and P ions from culture medium, while releasing Si and Sr ions from its backbone.Significance
Biodentine? interacts through elemental release/uptake with the cellular microenvironment, triggering odontogenic differentiation and biomineralization in a concentration-dependent manner. These results reveal a promising strategy for application of the calcium silicate based cement (Biodentine?) for vital pulp therapies of deciduous teeth in Paediatric Dentistry. 相似文献68.
Christine I. Vaitsopoulou Efstratios M. Kolibianakis Julia K. Bosdou Eirini Neofytou Stefania Lymperi Anastasios Makedos Despina Savvaidou Katerina Chatzimeletiou Grigoris F. Grimbizis Alexandros Lambropoulos Basil C. Tarlatzis 《Reproductive biomedicine online》2021,42(1):248-259
Research questionSex hormone-binding globulin (SHBG), androgen receptor (AR), LH beta polypeptide (LHB), progesterone receptor membrane component 1 (PGRMC1) and progesterone receptor membrane component 2 (PGRMC2) regulate follicle development and maturation. Their mRNA expression was assessed in peripheral blood mononuclear cells (PBMC) of normal and poor responders, during ovarian stimulation.DesignFifty-two normal responders and 15 poor responders according to the Bologna criteria were enrolled for IVF and intracytoplasmic sperm injection and stimulated with 200 IU of follitrophin alpha and gonadotrophin-releasing hormone antagonist. HCG was administered for final oocyte maturation. On days 1, 6 and 10 of stimulation, blood samples were obtained, serum hormone levels were measured, RNA was extracted from PBMC and real-time polymerase chain reaction was carried out to identify the mRNA levels. Relative mRNA expression of each gene was calculated by the comparative 2?DDCt method.ResultsDifferences between mRNA levels of each gene on the same time point between the two groups were not significant. PGRMC1 and PGRMC2 mRNA levels were downregulated, adjusted for ovarian response and age. Positive correlations between PGRMC1 and AR (standardized beta = 0.890, P < 0.001) from day 1 to 6 and PGRMC1 and LHB (standardized beta = 0.806, P < 0.001) from day 1 to 10 were found in poor responders. PGRMC1 and PGRMC2 were positively correlated on days 6 and 10 in normal responders.ConclusionsPGRMC1 and PGRMC2 mRNA are significantly decreased during ovarian stimulation, with some potential differences between normal and poor responders. 相似文献
69.
McAlinden C Khadka J Pesudovs K Skiadaresi E 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2012,28(5):313; author reply 313-313; author reply 314
70.
Eirini Skiadaresi Colm McAlinden Giuseppe Ravalico Jonathan Moore 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2012,250(9):1395-1398