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91.
Naomi Thielemans Sofie Demeyer Nicole Mentens Olga Gielen Sarah Provost Jan Cools 《Haematologica》2022,107(10):2304
TAL1 is ectopically expressed in about 30% of T-cell acute lymphoblastic leukemia (T-ALL) due to chromosomal rearrangements leading to the STIL-TAL1 fusion genes or due to non-coding mutations leading to a de novo enhancer driving TAL1 expression. Analysis of sequence data from T-ALL cases demonstrates a significant association between TAL1 expression and activating mutations of the PI3K-AKT pathway. We investigated the oncogenic function of TAL1 and the possible cooperation with PI3K-AKT pathway activation using isogenic pro-T-cell cultures ex vivo and in vivo leukemia models. We found that TAL1 on its own suppressed T-cell growth, in part by affecting apoptosis genes, while the combination with AKT pathway activation reduced apoptosis and was strongly driving cell proliferation ex vivo and leukemia development in vivo. As a consequence, we found that TAL1+AKTE17K transformed cells are more sensitive to PI3K-AKT pathway inhibition compared to AKTE17K transformed cells, related to the negative effect of TAL1 in the absence of activated PI3K-AKT signaling. We also found that both TAL1 and PI3K-AKT signaling increased the DNA-repair signature in T cells resulting in synergy between PARP and PI3K-AKT pathway inhibition. In conclusion, we have developed a novel mouse model for TAL1+AKTE17K driven T-ALL development and have identified a vulnerability of these leukemia cells to PI3K-AKT and PARP inhibitors. 相似文献
92.
Helena Biasizzo Barbara oba Frosina Ilovski Matev Harlander Matej Lukin Olga Blatnik Matja Turel Matev Srp
i
Izidor Kern Bojana Beovi 《Emerging infectious diseases》2022,28(12):2504
We report a case of human Dirofilaria repens infection in a woman in Slovenia who had concomitant pleural and subcutaneous manifestations of the infection. This case report illustrates the clinical course of a severe symptomatic parasitic infection that had multisystemic manifestations. 相似文献
93.
Considering the growing number of cancer cases around the world, natural products from the diet that exhibit potential antitumor properties are of interest. Our previous research demonstrated that fortification with iodine compounds is an effective way to improve the antioxidant potential of lettuce. The purpose of the present study was to evaluate the effect of iodine-biofortified lettuce on antitumor properties in human gastrointestinal cancer cell lines, gastric AGS and colon HT-29. Our results showed that extracts from iodine-biofortified lettuce reduce the viability and proliferation of gastric and colon cancer cells. The extracts mediated cell cycle arrest which was accompanied by inactivation of anti-apoptotic Bcl-2 and activation of caspases, as assessed by flow cytometry. However, extracts from lettuce fortified with organic forms of iodine acted more effectively than extracts from control and KIO3-enriched plants. Using quantitative PCR, we detected the increase in pro-apoptotic genes BAD, BAX and BID in AGS cells whereas up-regulation of cell cycle progression inhibitor CDKN2A and downregulation of pro-proliferative MDM2 in HT-29 cells. Interestingly, lettuce extracts led to down-regulation of pro-survival AKT1 and protooncogenic MDM2, which was consistent for extracts of lettuce fortified with organic form of iodine, 5-ISA, in both cell lines. MDM2 downregulation in HT-29 colon cancer cells was associated with RB1 upregulation upon 5-ISA-fortified lettuce extracts, which provides a link to the epigenetic regulation of tumor suppressor genes by RB/MDM2 pathway. Indeed, SEMA3A tumor suppressor gene was hypomethylated and upregulated in HT-29 cells treated with 5-ISA-fortified lettuce. Control lettuce exerted similar effects on RB/MDM2 pathway and SEMA3A epigenetic activation in HT-29 cells. Our findings suggest that lettuce as well as lettuce fortified with organic form of iodine, 5-ISA, may exert epigenetic anti-cancer effects that can be cancer type-specific. 相似文献
94.
Johanna M. Schwarzer Inga Meyhoefer Linda A. Antonucci Lana Kambeitz-Ilankovic Marian Surmann Olga Bienek Georg Romer Udo Dannlowski Tim Hahn Alexandra Korda Dominic B. Dwyer Anne Ruef Shalaila S. Haas Marlene Rosen Theresa Lichtenstein Stephan Ruhrmann Joseph Kambeitz Raimo K. R. Salokangas Christos Pantelis Frauke Schultze-Lutter Eva Meisenzahl Paolo Brambilla Alessandro Bertolino Stefan Borgwardt Rachel Upthegrove Nikolaos Koutsouleris Rebekka Lencer the PRONIA Consortium 《Neuropsychopharmacology》2022,47(12):2051
Subtle subjective visual dysfunctions (VisDys) are reported by about 50% of patients with schizophrenia and are suggested to predict psychosis states. Deeper insight into VisDys, particularly in early psychosis states, could foster the understanding of basic disease mechanisms mediating susceptibility to psychosis, and thereby inform preventive interventions. We systematically investigated the relationship between VisDys and core clinical measures across three early phase psychiatric conditions. Second, we used a novel multivariate pattern analysis approach to predict VisDys by resting-state functional connectivity within relevant brain systems. VisDys assessed with the Schizophrenia Proneness Instrument (SPI-A), clinical measures, and resting-state fMRI data were examined in recent-onset psychosis (ROP, n = 147), clinical high-risk states of psychosis (CHR, n = 143), recent-onset depression (ROD, n = 151), and healthy controls (HC, n = 280). Our multivariate pattern analysis approach used pairwise functional connectivity within occipital (ON) and frontoparietal (FPN) networks implicated in visual information processing to predict VisDys. VisDys were reported more often in ROP (50.34%), and CHR (55.94%) than in ROD (16.56%), and HC (4.28%). Higher severity of VisDys was associated with less functional remission in both CHR and ROP, and, in CHR specifically, lower quality of life (Qol), higher depressiveness, and more severe impairment of visuospatial constructability. ON functional connectivity predicted presence of VisDys in ROP (balanced accuracy 60.17%, p = 0.0001) and CHR (67.38%, p = 0.029), while in the combined ROP + CHR sample VisDys were predicted by FPN (61.11%, p = 0.006). These large-sample study findings suggest that VisDys are clinically highly relevant not only in ROP but especially in CHR, being closely related to aspects of functional outcome, depressiveness, and Qol. Findings from multivariate pattern analysis support a model of functional integrity within ON and FPN driving the VisDys phenomenon and being implicated in core disease mechanisms of early psychosis states.Subject terms: Predictive markers, Psychosis 相似文献
95.
96.
97.
Olga S. Volkova Abdellali Hadj-Azzem Gyorgy Remenyi Jose Emilio Lorenzo Pierre Monceau Alexander A. Sinchenko Alexander N. Vasiliev 《Materials》2022,15(24)
Terbium tritelluride, TbTe3, orders antiferromagnetically in three steps at TN1 = 6.7 K, TN2 = 5.7 K, and TN3 = 5.4 K, preceded by a correlation hump in magnetic susceptibility at T* ~8 K. Combining thermodynamic, i.e., specific heat Cp and magnetization M, and transport, i.e., resistance R, measurements we established the boundaries of two commensurate and one charge density wave modulated phases in a magnetic field oriented along principal crystallographic axes. Based on these measurements, the magnetic phase diagrams of TbTe3 at H‖a, H‖b and H‖c were constructed. 相似文献
98.
The center-periphery visual field axis guides early visual system organization with enhanced resources devoted to central vision leading to reduced peripheral performance relative to that of central vision (i.e., behavioral eccentricity effect) for many visual functions. The center-periphery organization extends to high-order visual cortex where, for example, the well-studied face-sensitive fusiform face area (FFA) shows sensitivity to central vision and the place-sensitive parahippocampal place area (PPA) shows sensitivity to peripheral vision. As we have recently found that face perception is more sensitive to eccentricity than place perception, here we examined whether these behavioral findings reflect differences in FFA's and PPA's sensitivities to eccentricity. We assumed FFA would show higher sensitivity to eccentricity than PPA would, but that both regions' modulation by eccentricity would be invariant to the viewed category. We parametrically investigated (fMRI, n = 32) how FFA's and PPA's activations are modulated by eccentricity (≤8°) and category (upright/inverted faces/houses) while keeping stimulus size constant. As expected, FFA showed an overall higher sensitivity to eccentricity than PPA. However, both regions' activation modulations by eccentricity were dependent on the viewed category. In FFA, a reduction of activation with growing eccentricity (“BOLD eccentricity effect”) was found (with different amplitudes) for all categories. In PPA however, qualitatively different BOLD eccentricity effect modulations were found (e.g., at 8° mild BOLD eccentricity effect for houses but a reverse BOLD eccentricity effect for faces and no modulation for inverted faces). Our results emphasize that peripheral vision investigations are critical to further our understanding of visual processing. 相似文献
99.
Vardan Arutiunian Giorgio Arcara Irina Buyanova Militina Gomozova Olga Dragoy 《Human brain mapping》2022,43(17):5370
Recent studies have revealed that gamma‐band oscillatory and transient evoked potentials may change with age during childhood. It is hypothesized that these changes can be associated with a maturation of GABAergic neurotransmission and, subsequently, the age‐related changes of excitation–inhibition balance in the neural circuits. One of the reliable paradigms for investigating these effects in the auditory cortex is 40 Hz Auditory Steady‐State Response (ASSR), where participants are presented with the periodic auditory stimuli. It is known that such stimuli evoke two types of responses in magnetoencephalography (MEG)—40 Hz steady‐state gamma response (or 40 Hz ASSR) and auditory evoked response called sustained Event‐Related Field (ERF). Although several studies have been conducted in children, focusing on the changes of 40 Hz ASSR with age, almost nothing is known about the age‐related changes of the sustained ERF to the same periodic stimuli and their relationships with changes in the gamma strength. Using MEG, we investigated the association between 40 Hz steady‐state gamma response and sustained ERF response to the same stimuli and also their age‐related changes in the group of 30 typically developing 7‐to‐12‐year‐old children. The results revealed a tight relationship between 40 Hz ASSR and ERF, indicating that the age‐related increase in strength of 40 Hz ASSR was associated with the age‐related decrease of the amplitude of ERF. These effects were discussed in the light of the maturation of the GABAergic system and excitation–inhibition balance development, which may contribute to the changes in ASSR and ERF. 相似文献