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161 results on '"Bazzi, Samer"'

1. GMM-based Codebook Construction and Feedback Encoding in FDD Systems

Author

Turan, Nurettin, Koller, Michael, Fesl, Benedikt, Bazzi, Samer, Xu, Wen, and Utschick, Wolfgang

Subjects
Computer Science - Information Theory, Electrical Engineering and Systems Science - Signal Processing
Abstract

We propose a precoder codebook construction and feedback encoding scheme which is based on Gaussian mixture models (GMMs). In an offline phase, the base station (BS) first fits a GMM to uplink (UL) training samples. Thereafter, it designs a codebook in an unsupervised manner by exploiting the GMM's clustering capability. We design one codebook entry per GMM component. After offloading the GMM-but not the codebook-to the mobile terminal (MT) in the online phase, the MT utilizes the GMM to determine the best fitting codebook entry. To this end, no channel estimation is necessary at the MT. Instead, the MT's observed signal is used to evaluate how responsible each component of the GMM is for the signal. The feedback consists of the index of the GMM component with the highest responsibility and the BS then employs the corresponding codebook entry. Simulation results show that the proposed codebook design and feedback encoding scheme outperforms conventional Lloyd clustering based codebook design algorithms, especially in configurations with reduced pilot overhead.

Published
2022

2. Unsupervised Learning of Adaptive Codebooks for Deep Feedback Encoding in FDD Systems

Author

Turan, Nurettin, Koller, Michael, Bazzi, Samer, Xu, Wen, and Utschick, Wolfgang

Subjects
Computer Science - Information Theory, Electrical Engineering and Systems Science - Signal Processing
Abstract

In this work, we propose a joint adaptive codebook construction and feedback generation scheme in frequency division duplex (FDD) systems. Both unsupervised and supervised deep learning techniques are used for this purpose. Based on a recently discovered equivalence of uplink (UL) and downlink (DL) channel state information (CSI) in terms of neural network learning, the codebook and associated deep encoder for feedback signaling is based on UL data only. Subsequently, the feedback encoder can be offloaded to the mobile terminals (MTs) to generate channel feedback there as efficiently as possible, without any training effort at the terminals or corresponding transfer of training and codebook data. Numerical simulations demonstrate the promising performance of the proposed method.

Published
2021

3. Resolving the spatial and cellular architecture of lung adenocarcinoma by multiregion single-cell sequencing

Author

Sinjab, Ansam, Han, Guangchun, Treekitkarnmongkol, Warapen, Hara, Kieko, Brennan, Patrick M, Dang, Minghao, Hao, Dapeng, Wang, Ruiping, Dai, Enyu, Dejima, Hitoshi, Zhang, Jiexin, Bogatenkova, Elena, Sanchez-Espiridion, Beatriz, Chang, Kyle, Little, Danielle R, Bazzi, Samer, Tran, Linh M, Krysan, Kostyantyn, Behrens, Carmen, Duose, Dzifa Y, Parra, Edwin R, Raso, Maria Gabriela, Solis, Luisa M, Fukuoka, Junya, Zhang, Jianjun, Sepesi, Boris, Cascone, Tina, Byers, Lauren Averett, Gibbons, Don L, Chen, Jichao, Moghaddam, Seyed Javad, Ostrin, Edwin J, Rosen, Daniel, Heymach, John V, Scheet, Paul, Dubinett, Steven M, Fujimoto, Junya, Wistuba, Ignacio I, Stevenson, Christopher S, Spira, Avrum, Wang, Linghua, and Kadara, Humam

Subjects
Biomedical and Clinical Sciences, Immunology, Rare Diseases, Lung Cancer, Lung, Genetics, Cancer, 1.1 Normal biological development and functioning, Underpinning research, Good Health and Well Being, Adenocarcinoma of Lung, CD8-Positive T-Lymphocytes, Humans, Lung Neoplasms, Single-Cell Analysis, Tumor Microenvironment, Oncology and Carcinogenesis, Biochemistry and cell biology, Oncology and carcinogenesis
Abstract

Little is known of the geospatial architecture of individual cell populations in lung adenocarcinoma (LUAD) evolution. Here, we perform single-cell RNA sequencing of 186,916 cells from five early-stage LUADs and 14 multiregion normal lung tissues of defined spatial proximities from the tumors. We show that cellular lineages, states, and transcriptomic features geospatially evolve across normal regions to LUADs. LUADs also exhibit pronounced intratumor cell heterogeneity within single sites and transcriptional lineage-plasticity programs. T regulatory cell phenotypes are increased in normal tissues with proximity to LUAD, in contrast to diminished signatures and fractions of cytotoxic CD8+ T cells, antigen-presenting macrophages, and inflammatory dendritic cells. We further find that the LUAD ligand-receptor interactome harbors increased expression of epithelial CD24, which mediates protumor phenotypes. These data provide a spatial atlas of LUAD evolution, and a resource for identification of targets for its treatment. SIGNIFICANCE: The geospatial ecosystem of the peripheral lung and early-stage LUAD is not known. Our multiregion single-cell sequencing analyses unravel cell populations, states, and phenotypes in the spatial and ecologic evolution of LUAD from the lung that comprise high-potential targets for early interception.This article is highlighted in the In This Issue feature, p. 2355.

Published
2021

4. On Reciprocity in Physically Consistent TDD Systems with Coupled Antennas

Author

Laas, Tobias, Nossek, Josef A., Bazzi, Samer, and Xu, Wen

Subjects
Computer Science - Information Theory, Electrical Engineering and Systems Science - Signal Processing
Abstract

We consider the reciprocity of the information-theoretic channel of Time Division Duplex (TDD) Multi-User-Multiple Input Multiple Output (MU-MIMO) systems in the up- and downlink. Specifically, we assume that the transmit and receive chains are reciprocal. We take the mutual coupling between the antenna elements at the base station and at the mobiles into account. Mutual coupling influences how to calculate transmit power and noise covariance. The analysis is based on the Multiport Communication Theory, which ensures that the information-theoretic model is consistent with physics. It also includes a detailed noise model. We show that due to the coupling, the information-theoretic up- and downlink channels do not fulfill the ordinary reciprocity relation, even if the input-output relation of the transmit voltage sources and the receive load voltages, i.e., the channel which is estimated with the help of pilot signals in the uplink, is reciprocal. This is a fundamental effect that is not considered otherwise. We show via Monte Carlo simulations that both, using the ordinary reciprocity relation, and not taking the coupling into account, significantly decreases the ergodic rates in single-user and the ergodic sum rates in multi-user systems.

Published
2019
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5. Analysis of the immune effects of two heat-killed whole cell mycobacterial preparations

Author

Bazzi, Samer Ihsan, Modjitahedi, Helmout, and Bahr, Georges

Subjects
616.9, Cancer studies, Other laboratory based clinical subjects
Abstract

Heat killed (HK) whole-cell preparations of the rapidly-growing mycobacteria, Mycobacterium vaccae and M. obuense, have been shown to possess immunomodulatory properties and hence a promising therapeutic potential. However, the outcome of interaction between both HK mycobacterial preparations and primary human innate immune cells remains largely undefined. The aim of this study was to investigate the regulation of surface expression of different categories of receptors on human neutrophils, monocytes, myeloid (m), and plasmacytiod (p) dendritic cells (DCs) following their in vitro stimulation with HK M. vaccae or M. obuense. Moreover, the pattern of cytokine and chemokine production in whole blood cultures and by purified total blood DCs in response to mycobacterial stimulation was examined. The current study also examined the phenotypic, functional, and transcriptomic profiles of non-activated and LPS/IFNy- activated human monocyte derived macrophages (MDM) differentiated with HK M. obuense (Mob-MDM), M-CSF (M-MDM), and GM-CSF (GM-MDM). Both HK mycobacterial preparations were found, first, to regulate the surface expression of adhesion, antigen-presenting, costimulatory, pattern recognition, cytokine/chemokine, complement, and Fe receptors on whole blood monocytes and neutrophils and, second, to induce mainly the production of pro-inflammatory cytokines/chemokines (CCL3, CCL5, CXCL8, IL-6, IL-12/23p40 and TNF-a) in whole blood cultures. Additionally, HK M. obuense was shown to primarily upregulate the surface expression of DCs and to augment the release of pro-inflammatory cytokines/chemokines (IL-6, IL12/23p40, TNF-a, CCL4, CCL5 and CXL8) by purified total blood DCs. Toll-like receptor (TLR-1) and TLR-2 were also identified to be engaged in mediating the HK M. obuense-induced up-regulation of CD11c and MHC class II surface expression on whole blood monocytes and mDCs. Of note, HK M. obeunse demonstrated an ability to trigger human monocyte-to-macrophange differentiation. Integrative phenotypic and genome-wide transcriptomic analysis revealed cytokine/chemokine secretion patterns, gene expression profiles and gene-gene networks in non-activated and LPS/IFNy-activated Mob-MDM that were quite distinct from those observed in non-activated and LPS/IFNy-activated M-MDM and GM-MDM. Overall, data from this study suggested that HK M. obuense exhibit potent immunomodulatory effects on primary human innate immune cells. Moreover, these results, together with previous clinical studies, point to a potential implication of HK M.obuense in the immunotherapy of cancer.

Published
2018

6. Reduction of hyperglycemia in STZ-induced diabetic mice by prophylactic treatment with heat-killed Mycobacterium aurum: possible effects on glucose utilization, mitochondrial uncoupling, and oxidative stress in liver and skeletal muscle.

Author

Abdallah, Farid, Bazzi, Samer, Akle, Charles, Bahr, Georges M., and Echtay, Karim S.

Subjects
GLYCEMIC control, UNCOUPLING proteins, MYCOBACTERIUM bovis, INTRADERMAL injections, GLUCOSE transporters, HYPERGLYCEMIA
Abstract

Background: In addition to conventional treatment and modifications in physical activity and diet, alternative strategies have been investigated to manage, prevent, or delay diabetes in humans. In this regard, one strategy has relied on the immunomodulatory properties of mycobacteria, whereby Bacillus Calmette-Guerin, an attenuated live strain of Mycobacterium bovis, has been shown to improve glycemic control in patients with diabetes and to alleviate hyperglycemia in selected murine models of diabetes. A novel heat-killed (HK) whole-cell preparation of Mycobacterium aurum (M. aurum) is currently under development as a potential food supplement; nevertheless, its potential bioactivity remains largely unknown. Thus, the present study investigated the potential prophylactic anti-diabetic effects of HK M. aurum in streptozotocin (STZ)-induced diabetic mice. Methods: Mice were divided into three groups: the STZ-induced diabetic group was injected with a single intraperitoneal high dose of STZ, the HK M. aurum-treated diabetic group was prophylactically treated with three doses of HK M. aurum 6 weeks before STZ injection, and the control non-diabetic group was given three intradermal injections of borate-buffered saline and an intraperitoneal injection of citrate buffer. Liver lactate dehydrogenase (LDH), uncoupling protein 2 (UCP2), and glucose transporter 2 (GLUT2) and skeletal muscle LDH, UCP3, and GLUT4 protein expression levels in different mouse groups were determined by Western blot. Results: Our results indicated that HK M. aurum did not cause any significant changes in glycemic levels of normal non-diabetic mice. Prophylactic administration of three doses of HK M. aurum to diabetic mice resulted in a significant reduction in their blood glucose levels when compared to those in control diabetic mice. Prophylactic treatment of diabetic mice with HK M. aurum significantly restored their disturbed protein expression levels of liver UCP2 and LDH as well as of skeletal muscle UCP3. On the other hand, prophylactic treatment of diabetic mice with HK M. aurum had no significant effect on their liver GLUT2 and skeletal muscle GLUT4 and LDH protein expression levels. Conclusions: Our findings provide the first evidence that HK M. aurum possesses a hyperglycemia-lowering capacity and might support its future use as a food supplement for the amelioration of diabetes. [ABSTRACT FROM AUTHOR]

Published
2024
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7. The in vitro effect of myeloperoxidase oxidized LDL on THP-1 derived macrophages.

Author

Jeradeh, Elias, Frangie, Christian, Bazzi, Samer, and Daher, Jalil

Subjects
FOAM cells, CELL death, REACTIVE oxygen species, MYELOPEROXIDASE, DISEASE progression, ATHEROSCLEROSIS
Abstract

Cardiovascular diseases (CVDs) linked to atherosclerosis remains the leading cause of death worldwide. Atherosclerosis is primarily caused by the accumulation of oxidized forms of low density lipoprotein (LDL) in macrophages (MΦs) in the subendothelial layer of arteries leading to foam cell and fatty streak formation. Many studies suggest that LDL that is modified by myeloperoxidase (MPO) is a key player in the development of atherosclerosis. MΦs can adopt a variety of functional phenotypes that include mainly the proinflammatory M1 and the anti-inflammatory M2 MΦ phenotypes which are both implicated in the process of atherogenesis. In fact, MΦs that reside in atherosclerostic lesions were shown to express a variety of phenotypes ranging between the M1- and M2 MΦ types. Recently, we pointed out the involvement of MPO oxidized-LDL (Mox-LDL) in increasing inflammation in MΦs by reducing their secretion of IL-10. Since little is known about Mox-LDL-mediated pro-atherosclerostic responses in MΦs, our study aimed at analyzing the in vitro effects of Mox-LDL at this level through making use of the well-established model of human THP-1-derived Mφs. Our results demonstrate that Mox-LDL has no effect on apoptosis, reactive oxygen species (ROS) generation and cell death in our cell model; yet, interestingly, our results show that Mox-LDL is significantly engulfed at a higher rate in the different MΦ subtypes supporting its key role in foam cell formation during the progression of the disease as well as previous data that were generated using another primary MΦ cell model of atherosclerosis. [ABSTRACT FROM AUTHOR]

Published
2024
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10. Minimizing Base Station Power Consumption

Author

Holtkamp, Hauke, Auer, Gunther, Bazzi, Samer, and Haas, Harald

Subjects
Computer Science - Information Theory
Abstract

We propose a new radio resource management algorithm which aims at minimizing the base station supply power consumption for multi-user MIMO-OFDM. Given a base station power model that establishes a relation between the RF transmit power and the supply power consumption, the algorithm optimizes the trade-off between three basic power-saving mechanisms: antenna adaptation, power control and discontinuous transmission. The algorithm comprises two steps: a) the first step estimates sleep mode duration, resource shares and antenna configuration based on average channel conditions and b) the second step exploits instantaneous channel knowledge at the transmitter for frequency selective time-variant channels. The proposed algorithm finds the number of transmit antennas, the RF transmission power per resource unit and spatial channel, the number of discontinuous transmission time slots, and the multi-user resource allocation, such that supply power consumption is minimized. Simulation results indicate that the proposed algorithm is capable of reducing the supply power consumption by between 25% and 40%, dependend on the system load., Comment: 27 pages

Published
2013
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11. The in vitroeffect of myeloperoxidase oxidized LDL on THP-1 derived macrophages

Author

Jeradeh, Elias, Frangie, Christian, Bazzi, Samer, and Daher, Jalil

Abstract

Cardiovascular diseases (CVDs) linked to atherosclerosis remains the leading cause of death worldwide. Atherosclerosis is primarily caused by the accumulation of oxidized forms of low density lipoprotein (LDL) in macrophages (MΦs) in the subendothelial layer of arteries leading to foam cell and fatty streak formation. Many studies suggest that LDL that is modified by myeloperoxidase (MPO) is a key player in the development of atherosclerosis. MΦs can adopt a variety of functional phenotypes that include mainly the proinflammatory M1 and the anti-inflammatory M2 MΦ phenotypes which are both implicated in the process of atherogenesis. In fact, MΦs that reside in atherosclerostic lesions were shown to express a variety of phenotypes ranging between the M1- and M2 MΦ types. Recently, we pointed out the involvement of MPO oxidized-LDL (Mox-LDL) in increasing inflammation in MΦs by reducing their secretion of IL-10. Since little is known about Mox-LDL-mediated pro-atherosclerostic responses in MΦs, our study aimed at analyzing the in vitroeffects of Mox-LDL at this level through making use of the well-established model of human THP-1-derived Mφs. Our results demonstrate that Mox-LDL has no effect on apoptosis, reactive oxygen species (ROS) generation and cell death in our cell model; yet, interestingly, our results show that Mox-LDL is significantly engulfed at a higher rate in the different MΦ subtypes supporting its key role in foam cell formation during the progression of the disease as well as previous data that were generated using another primary MΦ cell model of atherosclerosis.

Published
2024
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12. Supplementary Fig S1-S7 from Resolving the Spatial and Cellular Architecture of Lung Adenocarcinoma by Multiregion Single-Cell Sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, primary, Treekitkarnmongkol, Warapen, primary, Hara, Kieko, primary, Brennan, Patrick M., primary, Dang, Minghao, primary, Hao, Dapeng, primary, Wang, Ruiping, primary, Dai, Enyu, primary, Dejima, Hitoshi, primary, Zhang, Jiexin, primary, Bogatenkova, Elena, primary, Sanchez-Espiridion, Beatriz, primary, Chang, Kyle, primary, Little, Danielle R., primary, Bazzi, Samer, primary, Tran, Linh M., primary, Krysan, Kostyantyn, primary, Behrens, Carmen, primary, Duose, Dzifa Y., primary, Parra, Edwin R., primary, Raso, Maria Gabriela, primary, Solis, Luisa M., primary, Fukuoka, Junya, primary, Zhang, Jianjun, primary, Sepesi, Boris, primary, Cascone, Tina, primary, Byers, Lauren Averett, primary, Gibbons, Don L., primary, Chen, Jichao, primary, Moghaddam, Seyed Javad, primary, Ostrin, Edwin J., primary, Rosen, Daniel, primary, Heymach, John V., primary, Scheet, Paul, primary, Dubinett, Steven M., primary, Fujimoto, Junya, primary, Wistuba, Ignacio I., primary, Stevenson, Christopher S., primary, Spira, Avrum, primary, Wang, Linghua, primary, and Kadara, Humam, primary

Published
2023
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13. Data from Resolving the Spatial and Cellular Architecture of Lung Adenocarcinoma by Multiregion Single-Cell Sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, primary, Treekitkarnmongkol, Warapen, primary, Hara, Kieko, primary, Brennan, Patrick M., primary, Dang, Minghao, primary, Hao, Dapeng, primary, Wang, Ruiping, primary, Dai, Enyu, primary, Dejima, Hitoshi, primary, Zhang, Jiexin, primary, Bogatenkova, Elena, primary, Sanchez-Espiridion, Beatriz, primary, Chang, Kyle, primary, Little, Danielle R., primary, Bazzi, Samer, primary, Tran, Linh M., primary, Krysan, Kostyantyn, primary, Behrens, Carmen, primary, Duose, Dzifa Y., primary, Parra, Edwin R., primary, Raso, Maria Gabriela, primary, Solis, Luisa M., primary, Fukuoka, Junya, primary, Zhang, Jianjun, primary, Sepesi, Boris, primary, Cascone, Tina, primary, Byers, Lauren Averett, primary, Gibbons, Don L., primary, Chen, Jichao, primary, Moghaddam, Seyed Javad, primary, Ostrin, Edwin J., primary, Rosen, Daniel, primary, Heymach, John V., primary, Scheet, Paul, primary, Dubinett, Steven M., primary, Fujimoto, Junya, primary, Wistuba, Ignacio I., primary, Stevenson, Christopher S., primary, Spira, Avrum, primary, Wang, Linghua, primary, and Kadara, Humam, primary

Published
2023
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14. Supplementary Methods from Resolving the Spatial and Cellular Architecture of Lung Adenocarcinoma by Multiregion Single-Cell Sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, primary, Treekitkarnmongkol, Warapen, primary, Hara, Kieko, primary, Brennan, Patrick M., primary, Dang, Minghao, primary, Hao, Dapeng, primary, Wang, Ruiping, primary, Dai, Enyu, primary, Dejima, Hitoshi, primary, Zhang, Jiexin, primary, Bogatenkova, Elena, primary, Sanchez-Espiridion, Beatriz, primary, Chang, Kyle, primary, Little, Danielle R., primary, Bazzi, Samer, primary, Tran, Linh M., primary, Krysan, Kostyantyn, primary, Behrens, Carmen, primary, Duose, Dzifa Y., primary, Parra, Edwin R., primary, Raso, Maria Gabriela, primary, Solis, Luisa M., primary, Fukuoka, Junya, primary, Zhang, Jianjun, primary, Sepesi, Boris, primary, Cascone, Tina, primary, Byers, Lauren Averett, primary, Gibbons, Don L., primary, Chen, Jichao, primary, Moghaddam, Seyed Javad, primary, Ostrin, Edwin J., primary, Rosen, Daniel, primary, Heymach, John V., primary, Scheet, Paul, primary, Dubinett, Steven M., primary, Fujimoto, Junya, primary, Wistuba, Ignacio I., primary, Stevenson, Christopher S., primary, Spira, Avrum, primary, Wang, Linghua, primary, and Kadara, Humam, primary

Published
2023
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15. Supplementary Fig S8 from Resolving the Spatial and Cellular Architecture of Lung Adenocarcinoma by Multiregion Single-Cell Sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, primary, Treekitkarnmongkol, Warapen, primary, Hara, Kieko, primary, Brennan, Patrick M., primary, Dang, Minghao, primary, Hao, Dapeng, primary, Wang, Ruiping, primary, Dai, Enyu, primary, Dejima, Hitoshi, primary, Zhang, Jiexin, primary, Bogatenkova, Elena, primary, Sanchez-Espiridion, Beatriz, primary, Chang, Kyle, primary, Little, Danielle R., primary, Bazzi, Samer, primary, Tran, Linh M., primary, Krysan, Kostyantyn, primary, Behrens, Carmen, primary, Duose, Dzifa Y., primary, Parra, Edwin R., primary, Raso, Maria Gabriela, primary, Solis, Luisa M., primary, Fukuoka, Junya, primary, Zhang, Jianjun, primary, Sepesi, Boris, primary, Cascone, Tina, primary, Byers, Lauren Averett, primary, Gibbons, Don L., primary, Chen, Jichao, primary, Moghaddam, Seyed Javad, primary, Ostrin, Edwin J., primary, Rosen, Daniel, primary, Heymach, John V., primary, Scheet, Paul, primary, Dubinett, Steven M., primary, Fujimoto, Junya, primary, Wistuba, Ignacio I., primary, Stevenson, Christopher S., primary, Spira, Avrum, primary, Wang, Linghua, primary, and Kadara, Humam, primary

Published
2023
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16. Supplementary Tables from Resolving the Spatial and Cellular Architecture of Lung Adenocarcinoma by Multiregion Single-Cell Sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, primary, Treekitkarnmongkol, Warapen, primary, Hara, Kieko, primary, Brennan, Patrick M., primary, Dang, Minghao, primary, Hao, Dapeng, primary, Wang, Ruiping, primary, Dai, Enyu, primary, Dejima, Hitoshi, primary, Zhang, Jiexin, primary, Bogatenkova, Elena, primary, Sanchez-Espiridion, Beatriz, primary, Chang, Kyle, primary, Little, Danielle R., primary, Bazzi, Samer, primary, Tran, Linh M., primary, Krysan, Kostyantyn, primary, Behrens, Carmen, primary, Duose, Dzifa Y., primary, Parra, Edwin R., primary, Raso, Maria Gabriela, primary, Solis, Luisa M., primary, Fukuoka, Junya, primary, Zhang, Jianjun, primary, Sepesi, Boris, primary, Cascone, Tina, primary, Byers, Lauren Averett, primary, Gibbons, Don L., primary, Chen, Jichao, primary, Moghaddam, Seyed Javad, primary, Ostrin, Edwin J., primary, Rosen, Daniel, primary, Heymach, John V., primary, Scheet, Paul, primary, Dubinett, Steven M., primary, Fujimoto, Junya, primary, Wistuba, Ignacio I., primary, Stevenson, Christopher S., primary, Spira, Avrum, primary, Wang, Linghua, primary, and Kadara, Humam, primary

Published
2023
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18. Traffic Steering and Resource Management

Author

Bulakçı, Ömer, primary, Pedersen, Klaus, additional, Estevez, David Gutierrez, additional, Prasad, Athul, additional, Moya, Fernando Sanchez, additional, Christoffersson, Jan, additional, Yang, Yang, additional, Pateromichelakis, Emmanouil, additional, Arnold, Paul, additional, Svensson, Tommy, additional, Chen, Tao, additional, Miao, Honglei, additional, Kurras, Martin, additional, Bazzi, Samer, additional, Vassaki, Stavroula, additional, Kosmatos, Evangelos, additional, Kim, Kwang Taik, additional, Calochira, Giorgio, additional, Belschner, Jakob, additional, Barberis, Sergio, additional, and Şahin, Taylan, additional

Published
2018
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23. sj-docx-1-ini-10.1177_17534259221090679 - Supplemental material for The effect of myeloperoxidase-oxidized LDL on THP-1 macrophage polarization and repolarization

Author

Bazzi, Samer, Frangie, Christian, Azar, Eliana, and Daher, Jalil

Subjects
FOS: Clinical medicine, lipids (amino acids, peptides, and proteins), 110306 Endocrinology
Abstract

Supplemental material, sj-docx-1-ini-10.1177_17534259221090679 for The effect of myeloperoxidase-oxidized LDL on THP-1 macrophage polarization and repolarization by Samer Bazzi, Christian Frangie, Eliana Azar and Jalil Daher in Innate Immunity

Published
2022
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30. Abstract 130: Resolving the spatial and cellular architecture of lung adenocarcinoma by multi-region single-cell sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, additional, Treekitkarnmongkol, Warapen, additional, Hara, Kieko, additional, Brennan, Patrick, additional, Dang, Minghao, additional, Hao, Dapeng, additional, Wang, Ruiping, additional, Dai, Enyu, additional, Dejima, Hitoshi, additional, Zhang, Jiexin, additional, Bogatenkova, Elena, additional, Sanchez-Espiridion, Beatriz, additional, Chang, Kyle, additional, Little, Danielle R., additional, Bazzi, Samer, additional, Tran, Linh, additional, Krysan, Kostyantyn, additional, Behrens, Carmen, additional, Duose, Dzifa, additional, Parra, Edwin R., additional, Raso, Maria Gabriela, additional, Solis, Luisa M., additional, Fukuoka, Junya, additional, Zhang, Jianjun, additional, Sepesi, Boris, additional, Cascone, Tina, additional, Byers, Lauren A., additional, Gibbons, Don L., additional, Chen, Jichao, additional, Moghaddam, Seyed Javad, additional, Ostrin, Edwin J., additional, Rosen, Daniel G., additional, Heymach, John V., additional, Scheet, Paul, additional, Dubinett, Steven, additional, Wistuba, Ignacio I., additional, Fujimoto, Junya, additional, Stevenson, Christopher S., additional, Spira, Avrum E., additional, Wang, Linghua, additional, and Kadara, Humam, additional

Published
2021
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31. Weighted Sum Rate Maximization in Millimeter Wave Interfering Broadcast MIMO Channels

Author

Bazzi, Samer, Xu, Wen, and de Carvalho, Elisabeth

Abstract

In this paper, we propose weighted sum rate (WSR) maximization in millimeter wave interfering broadcast channels in the general case where both transmitters and receivers have multiple antennas, multiple radio frequency chains, and employ hybrid beamforming. We show how to adapt the WSR algorithm to the hybrid beamforming case, aiming at a practical low complexity design that allow a split between the analog beam alignment (BA) phase and digital precoder optimization such that transmit power constraint only needs to be satisfied by the digital precoders. We model the BA phase, after which transmitters and receivers have access to only low dimensional partial channel state information (CSI), corresponding to the matrix product of the analog precoder, physical channel and analog receive filter. In the MIMO broadcast channel, the proposed method shows a large performance improvement compared to block diagonalization (BD) and regularized BD schemes applied after BA, even in the unweighted case. In the MIMO interference channel, the proposed method shows significant gains with respect to literature methods based on orthogonal matching pursuit (OMP), even when the latter are run with perfect CSI. This is due to the fact that the OMP method results in additional leaked interference with every precoder or receive filter approximation. The obtained gains in all cases are larger with more constrained analog beamforming such as discrete Hadamard transform beams.

Published
2021

33. In vitro effects of azide-containing human CRP isoforms and oxLDL on U937-derived macrophage production of atherosclerosis-related cytokines

Author

Jundi, Dania, Krayem, Imtissal, Bazzi, Samer, and Karam, Marc

Subjects
Articles
Abstract

Atherosclerosis is an inflammatory chronic disease of the arterial wall. Monomeric (m) and pentameric (p) C-reactive protein (CRP) and oxidized low density lipoproteins (oxLDL) seem to affect the pattern of cytokine production by macrophages, thus playing an important role in atherogenesis. Azide, the commercial preservative of CRP, may influence its action in vitro. The present study aimed to determine the effects of both isoforms of azide-containing CRP (mCRP and pCRP) with and without oxLDL on cytokine production by U937-derived macrophages. U937 monocytes were cultured and differentiated into macrophages and treated with mCRP, pCRP, oxLDL and azide individually and in combination. ELISA were performed to measure the levels of interferon-γ (IFN-γ), interleukin (IL)-4, IL-6, IL-10 and tumor necrosis factor (TNF)-α in culture supernatants collected from U937-derived macrophages following their respective treatments. Most single and combined treatments, especially in triple combination, were able to downregulate the levels of IFN-γ and IL-6 compared with control untreated cells, whilst the combination of mCRP and pCRP increased IL-4 levels. Regarding IL-10, except for an increase induced by mCRP, no significant effect was caused by any treatment compared with the control. On the other hand, the levels of TNF-α were not significantly affected by any treatment except for a decreasing trend that was observed with mCRP/oxLDL treatment compared with control. By contrast, double azide caused a significant decrease in the levels of IFN-γ and IL-6. The results of the present study indicated that mCRP, pCRP, oxLD and possibly azide, individually or in different combinations, had the tendency to upregulate the expression of IL-4 and to downregulate that of the pro-atherogenic cytokines, IFN-γ and IL-6, suggesting that the intima microenvironment serves a crucial role in atherogenesis.

Published
2020

36. Resolving the spatial and cellular architecture of lung adenocarcinoma by multi-region single-cell sequencing

Author

Sinjab, Ansam, primary, Han, Guangchun, additional, Treekitkarnmongkol, Warapen, additional, Hara, Kieko, additional, Brennan, Patrick, additional, Dang, Minghao, additional, Hao, Dapeng, additional, Wang, Ruiping, additional, Dai, Enyu, additional, Dejima, Hitoshi, additional, Zhang, Jiexin, additional, Bogatenkova, Elena, additional, Sanchez-Espiridion, Beatriz, additional, Chang, Kyle, additional, Little, Danielle R., additional, Bazzi, Samer, additional, Tran, Linh, additional, Krysan, Kostyantyn, additional, Behrens, Carmen, additional, Duose, Dzifa, additional, Parra, Edwin R., additional, Raso, Maria Gabriela, additional, Solis, Luisa M., additional, Fukuoka, Junya, additional, Zhang, Jianjun, additional, Sepesi, Boris, additional, Cascone, Tina, additional, Byers, Lauren, additional, Gibbons, Don L., additional, Chen, Jichao, additional, Moghaddam, Seyed Javad, additional, Ostrin, Edwin J., additional, Rosen, Daniel G., additional, Heymach, John V., additional, Scheet, Paul, additional, Dubinett, Steven, additional, Fujimoto, Junya, additional, Wistuba, Ignacio I., additional, Stevenson, Christopher S., additional, Spira, Avrum E., additional, Wang, Linghua, additional, and Kadara, Humam, additional

Published
2020
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38. Effect of myeloperoxidase modified LDL on bovine and human aortic endothelial cells.

Author

El Samad, Ghadir, Bazzi, Samer, Karam, Marc, Zouaoui Boudjeltia, Karim, Vanhamme, Luc, Daher, Jalil, El Samad, Ghadir, Bazzi, Samer, Karam, Marc, Zouaoui Boudjeltia, Karim, Vanhamme, Luc, and Daher, Jalil

Abstract

Cardiovascular disease associated with atherosclerosis is a leading cause of death worldwide. Atherosclerosis is primarily caused by the dysfunction of vascular endothelial cells and the subendothelial accumulation of oxidized forms of low-density lipoproteins (LDL). Early observations have associated fibrin deposition with atheroma plaque formation, which has led to the proposition that a decrease in endothelial cell fibrinolysis may negatively influence atherogenesis. It has been recently demonstrated that myeloperoxidase modified LDL (MoxLDL) decreases endothelial cell profibrinolytic capacity in real-time. The present study investigated the role of MoxLDL in endothelial cell dysfunction by determining the molecules that may be involved in decreasing the fibrinolysis of human aortic endothelial cells (HAEC). Accordingly, reverse transcription-quantitative PCR was performed to screen for the differential expression of major genes that are implicated in the fibrinolytic process. In addition, the response of the latter cell type to MoxLDL was compared with bovine aortic endothelial (BAE) cells. Furthermore, the effect of the treatment on the generation of reactive oxygen species (ROS) was also determined. Although the current study did not demonstrate an association between MoxLDL treatment and a change in the expression of any major fibrinolytic factor in HAEC, a discrepancy between HAEC and BAE cells with respect to their response to modified LDL treatment was observed. The result have also demonstrated that MoxLDL does not increase ROS generation in HAEC as opposed to the other major type of modified LDL, cupper oxidized LDL (CuoxLDL) that was reported to exhibit a positive effect at this level. The present study provided important insight into the different effects of MoxLDL and CuoxLDL in endothelial cells, which may aid future studies to determine the various signaling pathways that are promoted by these molecules. The results of the present study may be utili, info:eu-repo/semantics/published

Published
2019

39. Anti-proliferative activity of yerba mate (Ilex paraguariensis) aqueous extracts on human colorectal cancer cell lines.

Author

Saleh, Ali Jason, Othman, Leen, Elchoueiry, Michel, Ghanem, Rita, Bazzi, Samer, El-Sabban, Marwan, and Abdel-Massih, Roula M.

Subjects
COLORECTAL cancer, CELL lines, MATE plant, CANCER cells, CELL cycle, CELL death, CELL analysis
Abstract

Background: Yerba mate, a popular, tealike beverage prepared from the dried leaves of Ilex paraguariensis, is widely consumed, and has several reported health benefits. Compared with other herbal teas, the effect of yerba mate on human cells in the context of cancer has not been extensively studied. The method of extraction of bioactive compounds from the yerba mate leaves plays an important role in its effect on cancer cells. Methods: In this study we assessed the viability, anti-proliferative, and apoptotic effect of the aqueous yerba mate extract, prepared using the same conditions employed for consumption, on different human colorectal cancer cell lines (Caco-2, HT-29, and HCT116) and on the non-tumorigenic human colon epithelial cell line (NCM460). Results: Cytotoxicity of aqueous yerba mate extract was studied and a dose-dependent decrease in viability was observed in all the tested cell lines. At 24 hrs., viability decreased to 19.7% with Caco-2 cells, 2.7% with HCT116, and 8.4% with HT-29 cells at a concentration of 4.8 mg/mL of yerba mate extract. The effect was less prominent on the NCM460 cell line where the viability of cells at the same concentration was 65.2%. Yerba mate extract also showed concentration-dependent anti-proliferative effects as determined by the WST-1 proliferation kit. IC50 values ranged between 0.22-0.69 mg/mL at 24 hr for cell lines tested. To study whether cell death was due to apoptosis, Caco-2 cells were stained with Annexin V-FITC assay and an increase in the percentage of late apoptotic Caco-2 cells was observed with yerba mate extract at 0.6-4.8 mg/mL. Cell cycle analysis using DNA content by flow cytometry showed an increase in the percentage of Caco-2 cells in the subG0/G1 phase and the G0/G1 phase after treatment with 2.4 mg/mL extract. Collectively, our data suggest that yerba mate aqueous extract exhibits an anti-proliferative effect on tested cell lines by inducing apoptosis. Conclusions: Yerba mate aqueous extract exhibits a strong anti-proliferative activity against adenocarcinoma cell lines studied and constitutes a promising functional food adjuvant to anti-cancer therapy. Further work is needed to identify active components and mechanisms of action. [ABSTRACT FROM AUTHOR]

Published
2021
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48. Linear Precoding and Analysis of Performance Criteria in MIMO Interference Channels

Author

Bazzi, Samer, Utschick, Wolfgang (Prof. Dr.), and Gesbert, David (Prof., Ph.D.)

Subjects
Ingenieurwissenschaften, ddc:620
Abstract

This thesis treats the downlink transmission in multi-antenna (MIMO) wireless interference channels, and characterizes the spectral efficiency of different linear precoding methods for such channels. These methods include interference alignment, maximum ratio transmission, and eigenmode precoding. The performance characterization of the latter two methods is especially important in massive MIMO scenarios, where these simple techniques exhibit a good performance. The analysis is mainly performed using random matrix theory and large system analysis, and includes the signaling overheads related to channel estimation which differ from one method to another. Diese Arbeit behandelt die Downlink-Übertragung im drahtlosen Interferenzkanal mit mehreren Sende- und Empfangsantennen (MIMO). Es wird die spekrale Effizienz verschiedener linearer Precoding-Verfahren für diese Kanäle charakterisiert. Unter den betrachteten Verfahren sind Interference Alignment, Maximum-ratio Combining und Eigenmode-Precoding. Die Charakterisierung der Leistungsfähigkeit der letzteren beiden Verfahren ist besonders wichtig für Massive-MIMO-Szenarien; hier zeigt sich hohe Leistungsfähigkeit. Die Analyse wird hauptsächlich anhand von Random Matrix-Theorie und Large System Analysis durchgeführt und beinhaltet die zusätzlich notwendige Signalisierung zur Kanalschätzung, welche sich zwischen den verschiedenen Methoden unterscheidet.

Published
2016

49. Defining Genome-Wide Expression and Phenotypic Contextual Cues in Macrophages Generated by Granulocyte/Macrophage Colony-Stimulating Factor, Macrophage Colony-Stimulating Factor, and Heat-Killed Mycobacteria

Author

Bazzi, Samer, primary, El-Darzi, Emale, additional, McDowell, Tina, additional, Modjtahedi, Helmout, additional, Mudan, Satvinder, additional, Achkar, Marcel, additional, Akle, Charles, additional, Kadara, Humam, additional, and Bahr, Georges M., additional

Published
2017
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