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41.
In this study, hydroxypropyl-β-cyclodextrin (HPβCD), HPβCD-conjugated magnetic nanoparticles (HPMN) and HPβCD-conjugated magnetic nanoparticles with polyurethane networks (HPMNPU) were synthesized and used as adsorbents for the removal of crystal violet (CV) and methyl violet (MV) dyes from aqueous solutions. Magnetic nanocomposites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The results of characterization analyses indicated that HPβCD was successfully modified with magnetic nanoparticles and polyurethane networks. In this work, a novel definitive screening design (DSD) was initially used to investigate the adsorption and elimination of dye impurities. This method allows a drastic reduction in the number of experiments needed to investigate those systems characterized by a large number of variables. The effects of nine quantitative parameters were investigated: initial dye concentration, adsorbent dose, contact time, temperature, pH, ionic strength, HMDI/HP ratio, MN/HP ratio, and stirrer speed. Analysis of a DSD model revealed that only four variables, namely, adsorbent dose, contact time, initial dye concentration and HMDI/HP ratio were statistically significant. Compared with HPMN, HPMNPU nanocomposites showed better adsorption performance for the removal of CV and MV from aqueous solutions. The maximum adsorption capacity values of HPMNPU were approximately 1269 mg g−1 and 1667 mg g−1 for CV and MV, respectively. This study showed that HPMNPU adsorbents exhibited high adsorption performance for the removal of CV and MV from water and could be promising adsorbent materials for the efficient removal of cationic dyes from wastewaters.Hydroxypropyl-β-cyclodextrin–polyurethane magnetic nanoconjugates possess adsorption properties favorablefor the purpose of removing crystal and methyl violet dyes. 相似文献
42.
Asma Delshad Mehrzad Saraei Safar Ali Alizadeh Soheila Rahimi Niaraki Mahmood Alipour Bahram Hosseinbigi Arezoo Bozorgomid Elham Hajialilo 《African health sciences》2020,20(3):1179
IntroductionBlastocystis is a common intestinal parasite of human and animal hosts. The parasite has 17 subtypes, and among those at least nine subtypes (ST1-ST9) are found in human hosts.ObjectiveThe aim of the present study was to investigate the presence of different subtypes of Blastocystis spp. among the patients referred to Velayat hospital of Qazvin province, Iran.MethodsOverall, 864 stool samples were examined by using formalin-ethyl acetate concentration method and Trichrome staining. All specimens were cultured in clotted fetal bovine medium. Later, DNA extraction and PCR amplification of 18S ribosomal RNA gene region was conducted and phylogenetic tree constructed.ResultsThe results revealed 7.9% (68/864) of the study population were infected with Blastocystis. Intestinal symptoms were observed in 61% (36/59) of individuals positive for Blastocystis, with abdominal pain in 58% (21/36) of cases which was more frequent than other intestinal signs. No significant relationship was observed among the study variables. By molecular and phylogenetic analysis, three subtypes ST1 (45%), ST2 (30%) and ST3 (23%) of parasite were identified.ConclusionThis study showed ST1 subtype was the predominant subtype among the positive specimens, meanwhile the highest haplotype and nucleotide diversity were clarified in ST3 subtype. 相似文献
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Apoorva Sikka Hamidreza Jamalabadi Marina Krylova Sarah Alizadeh Johan N. van der Meer Lena Danyeli Matthias Deliano Petya Vicheva Tim Hahn Thomas Koenig Deepti R. Bathula Martin Walter 《Human brain mapping》2020,41(9):2334-2346
Electroencephalogram (EEG) microstates that represent quasi‐stable, global neuronal activity are considered as the building blocks of brain dynamics. Therefore, the analysis of microstate sequences is a promising approach to understand fast brain dynamics that underlie various mental processes. Recent studies suggest that EEG microstate sequences are non‐Markovian and nonstationary, highlighting the importance of the sequential flow of information between different brain states. These findings inspired us to model these sequences using Recurrent Neural Networks (RNNs) consisting of long‐short‐term‐memory (LSTM) units to capture the complex temporal dependencies. Using an LSTM‐based auto encoder framework and different encoding schemes, we modeled the microstate sequences at multiple time scales (200–2,000 ms) aiming to capture stably recurring microstate patterns within and across subjects. We show that RNNs can learn underlying microstate patterns with high accuracy and that the microstate trajectories are subject invariant at shorter time scales (≤400 ms) and reproducible across sessions. Significant drop in the reconstruction accuracy was observed for longer sequence lengths of 2,000 ms. These findings indirectly corroborate earlier studies which indicated that EEG microstate sequences exhibit long‐range dependencies with finite memory content. Furthermore, we find that the latent representations learned by the RNNs are sensitive to external stimulation such as stress while the conventional univariate microstate measures (e.g., occurrence, mean duration, etc.) fail to capture such changes in brain dynamics. While RNNs cannot be configured to identify the specific discriminating patterns, they have the potential for learning the underlying temporal dynamics and are sensitive to sequence aberrations characterized by changes in metal processes. Empowered with the macroscopic understanding of the temporal dynamics that extends beyond short‐term interactions, RNNs offer a reliable alternative for exploring system level brain dynamics using EEG microstate sequences. 相似文献
45.
Neuregulin‐1 positively modulates glial response and improves neurological recovery following traumatic spinal cord injury
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Arsalan Alizadeh Scott M. Dyck Hardeep Kataria Ghazaleh M. Shahriary Dung H. Nguyen Kallivalappil T. Santhosh Soheila Karimi‐Abdolrezaee 《Glia》2017,65(7):1152-1175
Spinal cord injury (SCI) results in glial activation and neuroinflammation, which play pivotal roles in the secondary injury mechanisms with both pro‐ and antiregeneration effects. Presently, little is known about the endogenous molecular mechanisms that regulate glial functions in the injured spinal cord. We previously reported that the expression of neuregulin‐1 (Nrg‐1) is acutely and chronically declined following traumatic SCI. Here, we investigated the potential ramifications of Nrg‐1 dysregulation on glial and immune cell reactivity following SCI. Using complementary in vitro approaches and a clinically‐relevant model of severe compressive SCI in rats, we demonstrate that immediate delivery of Nrg‐1 (500 ng/day) after injury enhances a neuroprotective phenotype in inflammatory cells associated with increased interleukin‐10 and arginase‐1 expression. We also found a decrease in proinflammatory factors including IL‐1β, TNF‐α, matrix metalloproteinases (MMP‐2 and 9) and nitric oxide after injury. In addition, Nrg‐1 modulates astrogliosis and scar formation by reducing inhibitory chondroitin sulfate proteoglycans after SCI. Mechanistically, Nrg‐1 effects on activated glia are mediated through ErbB2 tyrosine phosphorylation in an ErbB2/3 heterodimer complex. Furthermore, Nrg‐1 exerts its effects through downregulation of MyD88, a downstream adaptor of Toll‐like receptors, and increased phosphorylation of Erk1/2 and STAT3. Nrg‐1 treatment with the therapeutic dosage of 1.5 μg/day significantly improves tissue preservation and functional recovery following SCI. Our findings for the first time provide novel insights into the role and mechanisms of Nrg‐1 in acute SCI and suggest a positive immunomodulatory role for Nrg‐1 that can harness the beneficial properties of activated glia and inflammatory cells in recovery following SCI. 相似文献
46.
Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time. The aim of this study was to optimize the delivery of the anticancer drug capecitabine (CAP) using nano PMs and cyclodextrin (CD) to allow the treatment of colon cancer. A pH-responsive copolymer was prepared and the variables of loading time, loading temperature, the amount of copolymer and also the ratio of acrylic/maleic copolymer to beta CD and the effect that these variables have on drug loading were investigated, with variable optimization studies carried out following a definitive screening design (DSD). The morphology and structure of the particles were determined by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. In vitro drug release exemplified that the micelles were pH-sensitive, this action was shown that firstly the drug release was done perfectly targeted and under control and secondly the drug has been released above 80% inside the colon.Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time. 相似文献
47.
David Akhavan Darya Alizadeh Dongrui Wang Michael R. Weist Jennifer K. Shepphird Christine E. Brown 《Immunological reviews》2019,290(1):60-84
Malignant brain tumors, including glioblastoma, represent some of the most difficult to treat of solid tumors. Nevertheless, recent progress in immunotherapy, across a broad range of tumor types, provides hope that immunological approaches will have the potential to improve outcomes for patients with brain tumors. Chimeric antigen receptors (CAR) T cells, a promising immunotherapeutic modality, utilizes the tumor targeting specificity of any antibody or receptor ligand to redirect the cytolytic potency of T cells. The remarkable clinical response rates of CD19‐targeted CAR T cells and early clinical experiences in glioblastoma demonstrating safety and evidence for disease modifying activity support the potential of further advancements ultimately providing clinical benefit for patients. The brain, however, is an immune specialized organ presenting unique and specific challenges to immune‐based therapies. Remaining barriers to be overcome for achieving effective CAR T cell therapy in the central nervous system (CNS) include tumor antigenic heterogeneity, an immune‐suppressive microenvironment, unique properties of the CNS that limit T cell entry, and risks of immune‐based toxicities in this highly sensitive organ. This review will summarize preclinical and clinical data for CAR T cell immunotherapy in glioblastoma and other malignant brain tumors, including present obstacles to advancement. 相似文献
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49.
Transformation of follicular lymphoma to diffuse large-cell lymphoma: alternative patterns with increased or decreased expression of c-myc and its regulated genes
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Lossos IS Alizadeh AA Diehn M Warnke R Thorstenson Y Oefner PJ Brown PO Botstein D Levy R 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(13):8886-8891
The natural history of follicular lymphoma (FL) is frequently characterized by transformation to a more aggressive diffuse large B cell lymphoma (DLBCL). We compared the gene-expression profiles between transformed DLBCL and their antecedent FL. No genes were observed to increase or decrease their expression in all of the cases of histological transformation. However, two different gene-expression profiles associated with the transformation process were defined, one in which c-myc and genes regulated by c-myc showed increased expression and one in which these same genes showed decreased expression. Further, there was a striking difference in gene-expression profiles between transformed DLBCL and de novo DLBCL, because the gene-expression profile of transformed DLBCL was more similar to their antecedent FL than to de novo DLBCL. This study demonstrates that transformation from FL to DLBCL can occur by alternative pathways and that transformed DLBCL and de novo DLBCL have very different gene-expression profiles that may underlie the different clinical behaviors of these two types of morphologically similar lymphomas. 相似文献
50.
Szomor A Molnár L Nagy A Dávid M Alizadeh H Kecskés M Vidra T Kereskai L Pajor L Losonczy H 《Orvosi hetilap》2000,141(48):2601-2604
The authors have treated 38 patients with chronic phase chronic myeloid leukemia in their single center in the last five years. Conventional chemotherapy provided about 40-50% hematological response, interferon-alpha seems to be more effective, complete hematological remission occurred in 65%. Interphase cytogenetics and fluorescein in situ hybridisation technique was used to measure the cytogenetic response. They observed complete cytogenetic remission in two cases (8%), major response in 11 (39%), minor response in 4 (15%) and minimal response in 4 cases (15%). Interferon-alpha is an effective, well-tolerated medicine in the treatment of chronic myeloid leukemia. 相似文献