712 results on '"M. Behar"'
Search Results
52. Mycobacterium tuberculosis-specific CD4+ and CD8+ T cells differ in their capacity to recognize infected macrophages.
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Jason D Yang, Daniel Mott, Rujapak Sutiwisesak, Yu-Jung Lu, Fiona Raso, Britni Stowell, Greg Hunter Babunovic, Jinhee Lee, Steve M Carpenter, Sing Sing Way, Sarah M Fortune, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Containment of Mycobacterium tuberculosis (Mtb) infection requires T cell recognition of infected macrophages. Mtb has evolved to tolerate, evade, and subvert host immunity. Despite a vigorous and sustained CD8+ T cell response during Mtb infection, CD8+ T cells make limited contribution to protection. Here, we ask whether the ability of Mtb-specific T cells to restrict Mtb growth is related to their capacity to recognize Mtb-infected macrophages. We derived CD8+ T cell lines that recognized the Mtb immunodominant epitope TB10.44-11 and compared them to CD4+ T cell lines that recognized Ag85b240-254 or ESAT63-17. While the CD4+ T cells recognized Mtb-infected macrophages and inhibited Mtb growth in vitro, the TB10.4-specific CD8+ T cells neither recognized Mtb-infected macrophages nor restricted Mtb growth. TB10.4-specific CD8+ T cells recognized macrophages infected with Listeria monocytogenes expressing TB10.4. However, over-expression of TB10.4 in Mtb did not confer recognition by TB10.4-specific CD8+ T cells. CD8+ T cells recognized macrophages pulsed with irradiated Mtb, indicating that macrophages can efficiently cross-present the TB10.4 protein and raising the possibility that viable bacilli might suppress cross-presentation. Importantly, polyclonal CD8+ T cells specific for Mtb antigens other than TB10.4 recognized Mtb-infected macrophages in a MHC-restricted manner. As TB10.4 elicits a dominant CD8+ T cell response that poorly recognizes Mtb-infected macrophages, we propose that TB10.4 acts as a decoy antigen. Moreover, it appears that this response overshadows subdominant CD8+ T cell response that can recognize Mtb-infected macrophages. The ability of Mtb to subvert the CD8+ T cell response may explain why CD8+ T cells make a disproportionately small contribution to host defense compared to CD4+ T cells. The selection of Mtb antigens for vaccines has focused on antigens that generate immunodominant responses. We propose that establishing whether vaccine-elicited, Mtb-specific T cells recognize Mtb-infected macrophages could be a useful criterion for preclinical vaccine development.
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- 2018
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53. Role of Granulocyte-Macrophage Colony-Stimulating Factor Production by T Cells during Mycobacterium tuberculosis Infection
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Alissa C. Rothchild, Britni Stowell, Girija Goyal, Cláudio Nunes-Alves, Qianting Yang, Kadamba Papavinasasundaram, Christopher M. Sassetti, Glenn Dranoff, Xinchun Chen, Jinhee Lee, and Samuel M. Behar
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GM-CSF ,Mycobacterium tuberculosis ,T cells ,cytokines ,lung infection ,macrophages ,Microbiology ,QR1-502 - Abstract
ABSTRACT Mice deficient for granulocyte-macrophage colony-stimulating factor (GM-CSF−/−) are highly susceptible to infection with Mycobacterium tuberculosis, and clinical data have shown that anti-GM-CSF neutralizing antibodies can lead to increased susceptibility to tuberculosis in otherwise healthy people. GM-CSF activates human and murine macrophages to inhibit intracellular M. tuberculosis growth. We have previously shown that GM-CSF produced by iNKT cells inhibits growth of M. tuberculosis. However, the more general role of T cell-derived GM-CSF during infection has not been defined and how GM-CSF activates macrophages to inhibit bacterial growth is unknown. Here we demonstrate that, in addition to nonconventional T cells, conventional T cells also produce GM-CSF during M. tuberculosis infection. Early during infection, nonconventional iNKT cells and γδ T cells are the main source of GM-CSF, a role subsequently assumed by conventional CD4+ T cells as the infection progresses. M. tuberculosis-specific T cells producing GM-CSF are also detected in the peripheral blood of infected people. Under conditions where nonhematopoietic production of GM-CSF is deficient, T cell production of GM-CSF is protective and required for control of M. tuberculosis infection. However, GM-CSF is not required for T cell-mediated protection in settings where GM-CSF is produced by other cell types. Finally, using an in vitro macrophage infection model, we demonstrate that GM-CSF inhibition of M. tuberculosis growth requires the expression of peroxisome proliferator-activated receptor gamma (PPARγ). Thus, we identified GM-CSF production as a novel T cell effector function. These findings suggest that a strategy augmenting T cell production of GM-CSF could enhance host resistance against M. tuberculosis. IMPORTANCE Mycobacterium tuberculosis is the bacterium that causes tuberculosis, the leading cause of death by any infection worldwide. T cells are critical components of the immune response to Mycobacterium tuberculosis. While gamma interferon (IFN-γ) is a key effector function of T cells during infection, a failed phase IIb clinical trial and other studies have revealed that IFN-γ production alone is not sufficient to control M. tuberculosis. In this study, we demonstrate that CD4+, CD8+, and nonconventional T cells produce GM-CSF during Mycobacterium tuberculosis infection in mice and in the peripheral blood of infected humans. Under conditions where other sources of GM-CSF are absent, T cell production of GM-CSF is protective and is required for control of infection. GM-CSF activation of macrophages to limit bacterial growth requires host expression of the transcription factor PPARγ. The identification of GM-CSF production as a T cell effector function may inform future host-directed therapy or vaccine designs.
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- 2017
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54. Vaccine-elicited memory CD4+ T cell expansion is impaired in the lungs during tuberculosis.
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Stephen M Carpenter, Jason D Yang, Jinhee Lee, Palmira Barreira-Silva, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Immunological memory is the key biological process that makes vaccines possible. Although tuberculosis vaccines elicit protective immunity in animals, few provide durable protection. To understand why protection is transient, we evaluated the ability of memory CD4+ T cells to expand, differentiate, and control Mycobacterium tuberculosis. Both naïve and memory CD4+ T cells initially proliferated exponentially, and the accumulation of memory T cells in the lung correlated with early bacterial control. However, later during infection, memory CD4+ T cell proliferation was curtailed and no protection was observed. We show that memory CD4+ T cells are first activated in the LN and their recruitment to the lung attenuates bacterial growth. However, their interaction with Mtb-infected macrophages does not promote continued proliferation. We conclude that a lack of sustained expansion by memory-derived T cells in the lung limits the durability of their protection, linking their slower expansion with transient protection in vaccinated mice.
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- 2017
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55. Host genetic background is a barrier to broadly effective vaccine protection: Relevance to BCG andMycobacterium tuberculosisInfection
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Rocky Lai, Diana Gong, Travis Williams, Abiola F. Ogunsola, Kelly Cavallo, Cecilia S. Lindestam Arlehamn, Sarah Acolatse, Gillian L. Beamer, Martin T. Ferris, Christopher M. Sassetti, Douglas A. Lauffenburger, and Samuel M. Behar
- Abstract
SummaryThe heterogeneity of immune responses observed in humans is difficult to model in standard inbred laboratory mice. To capture the diversity inherent in mice and better understand how host variation affects BCG-induced immunity againstMycobacterium tuberculosis, 24 unique Collaborative Cross (CC) recombinant inbred mouse strains and the C57BL/6 reference strain were vaccinated with or without BCG, and then challenged with low-dose aerosolized virulentM. tuberculosis. In contrast to standard lab strains, BCG protected only half of the CC strains tested. Furthermore, BCG efficacy is dissociable from inherent susceptibility to TB. As these strains differed primarily in the genes and alleles they inherited from the CC founder strains, we conclude that the host genetic background has a major influence on whether BCG confers protection againstM. tuberculosisinfection and indicates that host genetics should be considered as an important barrier to vaccine-mediated protection. Importantly, we wished to identify the components of the immune response stimulated by BCG, which were subsequently recalled after Mtb infection and associated with protection. The T cell immune response following BCG vaccination and Mtb challenge was extensively characterized. Although considerable diversity was observed, BCG vaccination had little impact on the composition of T cells recruited and maintained in the lung after infection. Instead, the variability was largely shaped by the genetic background. We developed models to detect vaccine-induced differences, which identified immune signatures associated with BCG-elicited protection against TB. Importantly, even when categorized as susceptible vs. resistant, and protected vs. unprotected, many of the protected CC strains had unique flavors of immunity, indicating multiple paths to protection. Thus, CC mice can be used to define correlates of protection and to identify vaccine strategies that protect a larger fraction of genetically diverse individuals instead of optimizing protection for a single genotype.
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- 2022
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56. Biventricular endocardial pacing and left bundle branch area pacing for cardiac resynchronization: Mechanistic insights from electrocardiographic imaging, acute hemodynamic response, and magnetic resonance imaging
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Mark K. Elliott, Marina Strocchi, Benjamin J. Sieniewicz, Baldeep Sidhu, Vishal Mehta, Nadeev Wijesuriya, Jonathan M. Behar, Andrew Thorpe, Dejana Martic, Tom Wong, Steven Niederer, and Christopher A. Rinaldi
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Abstract
Biventricular endocardial pacing (BiV-endo) has demonstrated superior cardiac resynchronization compared to conventional biventricular epicardial pacing (BiV-epi). Left bundle branch area pacing (LBBAP) may also achieve effective cardiac resynchronization therapy (CRT).The purpose of this study was to compare the acute electrical and hemodynamic effects of BiV-epi, BiV-endo, and LBBAP delivered from the LV endocardium and to assess how myocardial scar affects response.Eleven patients with indications for CRT underwent a temporary pacing study with electrocardiographic imaging (ECGi) and hemodynamic assessment. BiV-endo was delivered by stimulation of the left ventricular (LV) lateral wall, and LBBAP was delivered by stimulation of the LV septum, at the site of a Purkinje potential. LV activation time (LVAT-95), LV dyssynchrony index (LVDI), biventricular activation time (BIVAT-90), and biventricular dyssynchrony index (BIVDI) were calculated. Myocardial scar was assessed using magnetic resonance imaging (MRI).The protocol was completed in 10 patients. Compared to BiV-epi (LVAT-95: 79.2 ± 13.1 ms; LVDI: 26.6 ± 3.4 ms) LV resynchronization was superior during BiV-endo (LVAT-95: 48.5 ± 14.9 ms; P = .001; LVDI: 16.6 ± 6.4 ms; P = .002) and LBBAP (LVAT-95: 48.9 ± 12.5 ms; P = .001; LVDI: 15.3 ± 3.4 ms; P = .001). Biventricular resynchronization was similarly superior during BiV-endo and LBBAP vs BiV-epi (BIVAT-90 and BIVDI; P.05). The rate of acute hemodynamic responders was higher during BiV-endo (90%) and LBBAP (70%) vs BiV-epi (50%). The benefits of LBBAP (but not BiV-endo) on LV resynchronization were attenuated in a subset of 8 patients who underwent MRI.Our findings suggest superior electrical resynchronization and a higher proportion of acute hemodynamic responders during BiV-endo and LBBAP compared to BiV-epi. Electrical resynchronization was similar between BiV-endo and LBBAP; however, septal scar seemed to attenuate response to LBBAP.
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- 2022
57. Long-Term Impact of Body Mass Index on Survival of Patients Undergoing Cardiac Resynchronization Therapy: A Multi-Centre Study
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Antonio Creta, Jonathan M. Behar, Syed Ahsan, Martin Lowe, Alexandros Briasoulis, Catrin Sohrabi, Pedro Adragão, Sharad Agarwal, Anthony Chow, Nikolaos Papageorgiou, Christopher A. Rinaldi, Evaggelos Oikonomou, Mariana Goncalves, Tomáš Roubíček, Rudolf Duehmke, Dimitris Tousoulis, Pier D. Lambiase, Micaela Neto, Rostislav Polášek, Rui Providência, Richard J. Schilling, Wei-Yao Lim, Sérgio Barra, and Edward Rowland
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Cardiac resynchronization therapy ,030204 cardiovascular system & hematology ,Body Mass Index ,Cardiac Resynchronization Therapy ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Humans ,Medicine ,Cardiac Resynchronization Therapy Devices ,Obesity ,030212 general & internal medicine ,Mortality ,Risk factor ,Multi centre ,Aged ,Retrospective Studies ,Aged, 80 and over ,Heart Failure ,business.industry ,Middle Aged ,Overweight ,medicine.disease ,Defibrillators, Implantable ,Survival Rate ,Heart failure ,Ventricular assist device ,Cardiology ,Heart Transplantation ,Female ,Heart-Assist Devices ,Implant ,Cardiology and Cardiovascular Medicine ,business ,Body mass index - Abstract
Obesity is a risk factor for heart failure (HF), but its presence among HF patients may be associated with favorable outcomes. We investigated the long-term outcomes across different body mass index (BMI) groups, after cardiac resynchronization therapy (CRT), and whether defibrillator back-up (CRT-D) confers survival benefit. One thousand two-hundred seventy-seven (1,277) consecutive patients (mean age: 67.0 ± 12.7 years, 44.1% women, and mean BMI: 28.3 ± 5.6 Kg/m2) who underwent CRT implantation in 5 centers between 2000-2014 were followed-up for a median period of 4.9 years (IQR 2.4 to 7.5). More than 10% of patients had follow-up for ≥10 years. Patients were classified according to BMI as normal: 75% of patients, but were used less frequently in obese individuals. The composite endpoint of all-cause mortality or cardiac transplant/left ventricular assist device (LVAD) occurred in 50.9% of patients. At 10-year follow-up, less than a quarter of patients in the lowest and highest BMI categories were still alive and free from heart transplant/LVAD. After adjustment BMI of 25 to 29.9 Kg/m2 (HR = 0.73 [95%CI 0.56 to 0.96], p = 0.023) and use of CRT-D (HR = 0.74 [95% CI 0.55 to 0.98], p = 0.039) were independent predictors of survival free from LVAD/heart transplant. BMI of 25 to 29.9 Kg/m2 at the time of implant was independently associated with favourable long-term 10-year survival. Use of CRT-D was associated with improved survival irrespective of BMI class.
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- 2021
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58. Performance comparison: exome sequencing as a single test replacing Sanger sequencing
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Ephrat Levy-Lahad, Daniel Au, Concetta Bormans, Moshe Einhorn, Yuval Porat, Brent Manning, Arjan Bormans, Luisa Fernanda Sanchez, Hila Fridman, and Doron M. Behar
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0106 biological sciences ,0301 basic medicine ,Sanger sequencing ,General Medicine ,Computational biology ,Biology ,01 natural sciences ,DNA sequencing ,Human genetics ,Single test ,03 medical and health sciences ,symbols.namesake ,030104 developmental biology ,Performance comparison ,Genetics ,symbols ,Clinical case ,Molecular Biology ,Gene ,Exome sequencing ,010606 plant biology & botany - Abstract
Next generation sequencing tests are used routinely as first-choice tests in the clinic. However, systematic performance comparing the results of exome sequencing as a single test replacing Sanger sequencing of targeted gene(s) is still lacking. Performance comparison data are critically important for clinical case management. In this study, we compared Sanger-sequencing results of 258 genes to those obtained from next generation sequencing (NGS) using two exome-sequencing enrichment kits: Agilent-SureSelectQXT and Illumina-Nextera. Sequencing was performed on leukocytes and buccal-derived DNA from a single individual, and all 258 genes were sequenced a total of 11 times (using different sequencing methods and DNA sources). Sanger sequencing was completed for all exons, including flanking ± 8 bp regions. For the 258 genes, NGS mean coverage was > 20 × for > 98 and > 91% of the regions targeted by SureSelect and Nextera, respectively. Overall, 449 variants were identified in at least one experiment, and 407/449 (90.6%) were detected by all. Of the 42 discordant variants, 23 were determined as true calls, summing-up to a truth set of 430 variants. Sensitivity of true-variant detection was 99% for Sanger sequencing and 97–100% for the NGS experiments. Mean false-positive rates were 3.7E-6 for Sanger sequencing, 2.5E-6 for SureSelect-NGS and 5.2E-6 for Nextera-NGS. Our findings suggest a high overall concordance between Sanger sequencing and NGS performances. Both methods demonstrated false-positive and false-negative calls. High clinical suspicion for a specific diagnosis should, therefore, override negative results of either Sanger sequencing or NGS.
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- 2021
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59. First use of a rotating mechanical dilator sheath to extract an epicardial defibrillator lead from the pericardial space
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Vishal S Mehta, Mark K Elliott, William Regan, Jonathan M Behar, Eric Rosenthal, and Christopher A Rinaldi
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Pacemaker, Artificial ,Physiology (medical) ,Humans ,Cardiology and Cardiovascular Medicine ,Pericardium ,Defibrillators, Implantable - Published
- 2022
60. Identification of a novel mutation in the PNLIP gene in two brothers with congenital pancreatic lipase deficiency
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Doron M. Behar, Lina Basel-Vanagaite, Fabian Glaser, Marielle Kaplan, Shay Tzur, Nurit Magal, Tal Eidlitz-Markus, Yishay Haimi-Cohen, Galit Sarig, Concetta Bormans, Mordechai Shohat, and Avraham Zeharia
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dietary fat ,absorption ,consanguineous ,Arab ,Biochemistry ,QD415-436 - Abstract
Congenital pancreatic lipase (PNLIP) deficiency is a rare monoenzymatic form of exocrine pancreatic failure characterized by decreased absorption of dietary fat and greasy voluminous stools, but apparent normal development and an overall good state of health. While considered to be an autosomal recessive state affecting a few dozens of individuals world-wide and involving the PNLIP gene, no causative mutations for this phenotype were so far reported. Here, we report the identification of the homozygote missense mutation, Thr221Met [c.662C>T], in two brothers from a consanguineous family of Arab ancestry. The observed genotypes among the family members were concordant with an autosomal recessive mode of inheritance but moreover a clear segregation between the genotype state and the serum PNLIP activity was evident. Based on biophysical computational tools, we suggest the mutation disrupts the protein's stability and impairs its normal function. Although the role of PNLIP is well established, our observations provide genetic evidence that PNLIP mutations are causative for this phenotype.
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- 2014
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61. Noninvasive electrocardiographic assessment of ventricular activation and remodeling response to cardiac resynchronization therapy
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Tom Jackson, Vishal Mehta, Cheng Yao, Justin Gould, Steven A. Niederer, Baldeep S. Sidhu, Christopher A. Rinaldi, Helder Pereira, Gerald Carr-White, Jonathan M. Behar, Simon Claridge, and Mark K. Elliott
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medicine.medical_specialty ,medicine.medical_treatment ,Cardiac resynchronization therapy ,Heart failure ,Clinical ,ECG imaging ,Statistical significance ,Internal medicine ,Devices ,Diseases of the circulatory (Cardiovascular) system ,Medicine ,Lead (electronics) ,Body surface mapping ,business.industry ,Left bundle branch block ,medicine.disease ,medicine.anatomical_structure ,LV activation mapping ,Ventricle ,RC666-701 ,Cardiology ,Implant ,business - Abstract
Background Cardiac resynchronization therapy (CRT) produces acute changes in electric resynchronization that can be measured noninvasively with electrocardiographic body surface mapping (ECGi). The relation between baseline acute electrophysiology metrics and their manipulation with CRT and reverse remodeling is unclear. Objective To test (ECGi) derived parameters of electrical activation as predictors of volumetric response to CRT. Methods ECGi was performed in 21 patients directly following CRT implant. Activation parameters (left ventricular total activation time [LVtat], global biventricular total activation time [VVtat], global left/right ventricular electrical synchrony [VVsync], and global left ventricular dispersion of activation times [LVdisp]) were measured at baseline and following echocardiographically optimized CRT. Remodeling response (>15% reduction left ventricular end-systolic volume) was assessed 6 months post CRT. Results Patients were aged 68.9 ± 12.1 years, 81% were male, and 57% were ischemic. Baseline measures of dyssynchrony were more pronounced in left bundle branch block (LBBB) vs non-LBBB. ECGi demonstrated a trend of greater interventricular dyssynchrony between responders and nonresponders that did not reach statistical significance (VVsync: -45.7 ± 22.4 ms vs -25.1 ± 29.3 ms, P = .227). Remaining activation parameters were similar between responders and nonresponders (VVtat 101 ± 22.0 ms vs 98.9 ± 23.4 ms, P = .838; LVtat 86.4 ± 17.1 ms vs 85.1 ± 27.7 ms, P = .904; LVdisp 28.2 ± 6.3 ms vs 27.0 ± 8.7 ms, P = .726). In volumetric responders activation parameters were significantly improved with CRT compared to nonresponders: VV sync (-45.67 ± 22.41 ms vs 2.33±18.87 ms, P = .001), VVtat (101 ± 22.04 ms vs 71 ± 14.01 ms, P = .002), LVtat (86.44 ± 17.15 ms vs 67.67 ± 11.31 ms, P = .006), and LVdisp (28.22 ± 6.3 ms vs 21.56 ± 4.45 ms, P = .008). Conclusion Baseline ECGi activation times did not predict CRT volumetric response. Volumetric responders exhibited significant improvements in ECGi-derived metrics with CRT. ECGi does not select CRT candidates but may be a useful adjunct to guide left ventricle lead implants and to perform postimplant CRT optimization., Graphical abstract
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- 2021
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62. Tuberculosis Susceptibility and Vaccine Protection Are Independently Controlled by Host Genotype
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Clare M. Smith, Megan K. Proulx, Andrew J. Olive, Dominick Laddy, Bibhuti B. Mishra, Caitlin Moss, Nuria Martinez Gutierrez, Michelle M. Bellerose, Palmira Barreira-Silva, Jia Yao Phuah, Richard E. Baker, Samuel M. Behar, Hardy Kornfeld, Thomas G. Evans, Gillian Beamer, and Christopher M. Sassetti
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Microbiology ,QR1-502 - Abstract
ABSTRACT The outcome of Mycobacterium tuberculosis infection and the immunological response to the bacillus Calmette-Guerin (BCG) vaccine are highly variable in humans. Deciphering the relative importance of host genetics, environment, and vaccine preparation for the efficacy of BCG has proven difficult in natural populations. We developed a model system that captures the breadth of immunological responses observed in outbred individual mice, which can be used to understand the contribution of host genetics to vaccine efficacy. This system employs a panel of highly diverse inbred mouse strains, consisting of the founders and recombinant progeny of the “Collaborative Cross” project. Unlike natural populations, the structure of this panel allows the serial evaluation of genetically identical individuals and the quantification of genotype-specific effects of interventions such as vaccination. When analyzed in the aggregate, our panel resembled natural populations in several important respects: the animals displayed a broad range of susceptibility to M. tuberculosis, differed in their immunological responses to infection, and were not durably protected by BCG vaccination. However, when analyzed at the genotype level, we found that these phenotypic differences were heritable. M. tuberculosis susceptibility varied between lines, from extreme sensitivity to progressive M. tuberculosis clearance. Similarly, only a minority of the genotypes was protected by vaccination. The efficacy of BCG was genetically separable from susceptibility to M. tuberculosis, and the lack of efficacy in the aggregate analysis was driven by nonresponsive lines that mounted a qualitatively distinct response to infection. These observations support an important role for host genetic diversity in determining BCG efficacy and provide a new resource to rationally develop more broadly efficacious vaccines. IMPORTANCE Tuberculosis (TB) remains an urgent global health crisis, and the efficacy of the currently used TB vaccine, M. bovis BCG, is highly variable. The design of more broadly efficacious vaccines depends on understanding the factors that limit the protection imparted by BCG. While these complex factors are difficult to disentangle in natural populations, we used a model population of mice to understand the role of host genetic composition in BCG efficacy. We found that the ability of BCG to protect mice with different genotypes was remarkably variable. The efficacy of BCG did not depend on the intrinsic susceptibility of the animal but, instead, correlated with qualitative differences in the immune responses to the pathogen. These studies suggest that host genetic polymorphism is a critical determinant of vaccine efficacy and provide a model system to develop interventions that will be useful in genetically diverse populations.
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- 2016
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63. TIM3 Mediates T Cell Exhaustion during Mycobacterium tuberculosis Infection.
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Pushpa Jayaraman, Miye K Jacques, Chen Zhu, Katherine M Steblenko, Britni L Stowell, Asaf Madi, Ana C Anderson, Vijay K Kuchroo, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
While T cell immunity initially limits Mycobacterium tuberculosis infection, why T cell immunity fails to sterilize the infection and allows recrudescence is not clear. One hypothesis is that T cell exhaustion impairs immunity and is detrimental to the outcome of M. tuberculosis infection. Here we provide functional evidence for the development T cell exhaustion during chronic TB. Second, we evaluate the role of the inhibitory receptor T cell immunoglobulin and mucin domain-containing-3 (TIM3) during chronic M. tuberculosis infection. We find that TIM3 expressing T cells accumulate during chronic infection, co-express other inhibitory receptors including PD1, produce less IL-2 and TNF but more IL-10, and are functionally exhausted. Finally, we show that TIM3 blockade restores T cell function and improves bacterial control, particularly in chronically infected susceptible mice. These data show that T cell immunity is suboptimal during chronic M. tuberculosis infection due to T cell exhaustion. Moreover, in chronically infected mice, treatment with anti-TIM3 mAb is an effective therapeutic strategy against tuberculosis.
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- 2016
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64. Pacemaker‐mediated tachycardia in a dual‐lead CRT‐D: What is the mechanism?
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Christopher Monkhouse, Alex Cambridge, Jonathan M. Behar, and Anthony W.C. Chow
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Cardiomyopathy, Dilated ,Male ,Tachycardia ,medicine.medical_specialty ,Exacerbation ,Bundle-Branch Block ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Humans ,Medicine ,Cardiac Resynchronization Therapy Devices ,cardiovascular diseases ,030212 general & internal medicine ,Lead (electronics) ,Aged ,Heart Failure ,Ejection fraction ,business.industry ,Left bundle branch block ,Stroke Volume ,Dilated cardiomyopathy ,General Medicine ,Symptom Flare Up ,medicine.disease ,Equipment Failure Analysis ,Heart failure ,cardiovascular system ,Cardiology ,Implant ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Abstract
A 73-year-old gentleman with dilated cardiomyopathy, left bundle branch block and a left ventricular (LV) ejection fraction of 20% was implanted with two LV leads in a tri-ventricular cardiac resynchronisation therapy defibrillator (CRT-D) trial. As a part of the trial he was programmed with fusion-based CRT therapy with dual LV lead only pacing. The patient presented to local heart failure service 12 years after implant, after a positive response to CRT therapy, with increase in fatigue, shortness of breath and bilateral pitting oedema. The patient sent a remote monitoring transmission that suggested loss of capture on one of the LV leads. This coupled with atrial ectopics was producing a high burden of pacemaker-mediated tachycardia (PMT) that was not seen when both LV leads had been capturing. What is the mechanism for this? Dual LV-lead tri-ventricular leads have been shown to have variable improvements in CRT response but with an increased complexity of implant procedure. This is the first case report of PMT-induced heart failure exacerbation in a tri-ventricular device following loss of LV capture of one lead.
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- 2020
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65. Dissecting the paternal founders of Mundari (Austroasiatic) speakers associated with the language dispersal in South Asia
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Prajjval Pratap Singh, Shani Vishwakarma, Doron M. Behar, Toomas Kivisild, Arno Pilvar, Richard Villems, Gyaneshwer Chaubey, Gazi Nurun Nahar Sultana, Mait Metspalu, Monika Karmin, George van Driem, and Siiri Rootsi
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Male ,South asia ,Human Migration ,410 Linguistics ,Brief Communication ,Haplogroup ,Southeast asia ,Evolution, Molecular ,03 medical and health sciences ,Asian People ,Extant taxon ,Genetics ,Humans ,Asia, Southeastern ,Genetics (clinical) ,Language ,Bangladesh ,0303 health sciences ,Chromosomes, Human, Y ,Phylogenetic tree ,030305 genetics & heredity ,Founder Effect ,Pedigree ,Geography ,Haplotypes ,Evolutionary biology ,Biological dispersal - Abstract
The phylogenetic analysis of Y chromosomal haplogroup O2a-M95 was crucial to determine the nested structure of South Asian branches within the larger tree, predominantly present in East and Southeast Asia. However, it had previously been unclear that how many founders brought the haplogroup O2a-M95 to South Asia. On the basis of the updated Y chromosomal tree for haplogroup O2a-M95, we analysed 1437 male samples from South Asia for various novel downstream markers, carefully selected from the extant phylogenetic tree. With this increased resolution of genetic markers, we were able to identify at least three founders downstream to haplogroup O2a-M95, who are likely to have been associated with the dispersal of Austroasiatic languages to South Asia. The fourth founder was exclusively present amongst Tibeto-Burman speakers of Manipur and Bangladesh. In sum, our new results suggest the arrival of Austroasiatic languages in South Asia during last 5000 years.
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- 2020
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66. Teaching clinicians practical genomic medicine: 7 years’ experience in a tertiary care center
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Naama Oresntein, Arie Koifman, Efrat Sofrin-Drucker, Adi Reches, Noa Rhurman-Shahar, Gal Zaks-Hoffer, Nurit Magal, Doron M. Behar, Yael Goldberg, Daphna Marom, Mordechai Shohat, Lina Basel-Salmon, Noa Shefer Averbuch, Lily Bazak, Reut Matar, Sagi Josefberg, Nesia Kropach-Gilad, Rachel Michaelson-Cohen, Rivka Sukenik-Halevy, Avi Fellner, Liat Salzer-Sheelo, Monika Weiss-Hubshmann, and Idit Maya
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medicine.medical_specialty ,business.industry ,media_common.quotation_subject ,Tertiary care ,Literacy ,Clinical Practice ,Knowledge change ,Family medicine ,Program completion ,Medicine ,Genomic medicine ,business ,Genetics (clinical) ,media_common - Abstract
Increased implementation of complex genetic technologies in clinical practice emphasizes the urgency of genomic literacy and proficiency for medical professionals. We evaluated our genomic education model. We assessed the 5-day, extended format program, encompassing lectures, videos, interactive tests, practice cases, and clinical exercises. Pre- and post questionnaires assessed knowledge change, using t-tests to compare groups. Satisfaction on program completion and after 3 years were evaluated. Implementation in other centers determined acceptability. During 2012–2018, 774 clinicians from multiple disciplines and career stages attended 35 programs; 334 (43%) attended the 5-day extended format. Evaluations showed significant improvement of genomic literacy (mean 15.05/100 points, p
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- 2020
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67. Percutaneous left ventricular endocardial leads: adverse outcomes and a percutaneous extraction case series
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Mehul Dhinoja, Vivienne Ezzat, Jonathan M. Behar, Malcolm Finlay, Edward Rowland, and Simon Sporton
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medicine.medical_specialty ,Percutaneous ,Adverse outcomes ,medicine.medical_treatment ,Cardiac resynchronization therapy ,030204 cardiovascular system & hematology ,LV endocardial ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Medicine ,Case Series ,AcademicSubjects/MED00200 ,Pacing lead ,030212 general & internal medicine ,Adverse effect ,Venous anatomy ,Lead (electronics) ,Endocardium ,business.industry ,Cardiology ,Transvenous extraction ,Cardiology and Cardiovascular Medicine ,business ,Coronary venous tree ,Arrhythmias / Electrophysiology - Abstract
Background Conventional cardiac resynchronization therapy (CRT) involves the placement of an epicardial left ventricular (LV) lead through the coronary venous tree. However, alternative approaches of delivering CRT have been sought for patients who fail to respond to conventional methods or for those where coronary venous anatomy is unfavourable. Biventricular pacing through an endocardial LV lead has potential advantages; however, the long-term clinical and safety data are not known. Case summary This article details a case series of four patients with endocardial LV leads; three of these for previously failed conventional CRT and a fourth for an inadvertently placed defibrillator lead. Discussion We describe the clinical course and adverse events associated with left-sided leads and subsequently describe the safe and feasible method of percutaneous extraction.
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- 2020
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68. The novel founder homozygous V225M mutation in the HSD17B3 gene causes aberrant splicing and XY-DSD
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Ephrat Levy-Lahad, Sharon Zeligson, Carmit Avnon Ziv, Abdulsalam Abu-Libdeh, David Zangen, Paul Renbaum, Tehila Klopstock, Eran Lavi, Reeval Segel, Floris Levy-Khademi, Doron M. Behar, Boris Chertin, Tzvia Rosen, Shira Perlberg-Bengio, and Fouad Zahdeh
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Genetics ,Sanger sequencing ,Endocrinology, Diabetes and Metabolism ,Haplotype ,030209 endocrinology & metabolism ,Chromosome 9 ,Biology ,03 medical and health sciences ,symbols.namesake ,Exon ,0302 clinical medicine ,Endocrinology ,030220 oncology & carcinogenesis ,RNA splicing ,Mutation (genetic algorithm) ,symbols ,Allele ,Gene - Abstract
Mutations in the gene HSD17B3 encoding the 17-beta hydroxysteroid dehydrogenase 3 enzyme cause testosterone insufficiency leading to XY disorders of sex development. In this study the clinical and molecular characteristics of three patients from consanguineous families are elucidated. We identified three patients from two unrelated families with XY DSD and a novel homozygous HSD17B3:c. 673G>A mutation. The effect of the mutation on splicing was determined in RNA extracted from the testis of one patient. Three patients presented at ages 0.1, 8 and 0.7 years with ambiguous genitalia and an XY Karyotype. Endocrine workup showed normal cortisol and mineralocorticoid levels with a low testosterone/androstenedione ratio. Whole-exome sequencing, carried out in the first family, revealed a homozygous novel mutation in the HSD17B3 gene: c. 673G>A, p. V225M. The same mutation was found by Sanger sequencing in the third unrelated patient. Haplotype analysis of a 4 Mb region surrounding the HSD17B3 gene on chromosome 9 revealed that the mutation resides on the same allele in all three patients. The mutation, being the first nucleic acid on exon 10, affects splicing and causes exon 10 skipping in one of our patients’ testes. The novel homozygous c. 673G>A, p. V225M mutation in the 17HSDB3 gene is likely a founder mutation and causes severe XY-DSD. It changes a conserved amino acid residue, and also alters 17HSDB3 gene transcription by causing skipping of exon 10, thereby contributing to an imbalance in the relevant protein isoforms and consequently, significant decreased 17HDSB3 enzymatic activity.
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- 2020
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69. Enriching and Characterizing T-Cell Repertoires from 3' Barcoded Single-Cell Whole Transcriptome Amplification Products
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Tasneem Jivanjee, Samira Ibrahim, Sarah K. Nyquist, G. James Gatter, Joshua D. Bromley, Swati Jaiswal, Bonnie Berger, Samuel M. Behar, J. Christopher Love, and Alex K. Shalek
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Genomics (q-bio.GN) ,Sequence Analysis, RNA ,T-Lymphocytes ,FOS: Biological sciences ,Receptors, Antigen, T-Cell ,Quantitative Biology - Genomics ,Single-Cell Analysis ,Transcriptome ,Quantitative Biology - Quantitative Methods ,Article ,Quantitative Methods (q-bio.QM) - Abstract
Antigen-specific T cells play an essential role in immunoregulation and diseases such as cancer. Characterizing the T cell receptor (TCR) sequences that encode T cell specificity is critical for elucidating the antigenic determinants of immunological diseases and designing therapeutic remedies. However, methods of obtaining single-cell TCR sequencing data are labor and cost intensive, requiring cell sorting and full length single-cell RNA-sequencing (scRNA-seq). New high-throughput 3' cell-barcoding scRNA-seq methods can simplify and scale this process; however, they do not routinely capture TCR sequences during library preparation and sequencing. While 5' cell-barcoding scRNA-seq methods can be used to examine TCR repertoire at single-cell resolution, it requires specialized reagents which cannot be applied to samples previously processed using 3' cell-barcoding methods. Here, we outline a method for sequencing TCR$\alpha$ and TCR$\beta$ transcripts from samples already processed using 3' cell-barcoding scRNA-seq platforms, ensuring TCR recovery at a single-cell resolution. In short, a fraction of the 3' barcoded whole transcriptome amplification (WTA) product typically used to generate a massively parallel 3' scRNA-seq library is enriched for TCR transcripts using biotinylated probes, and further amplified using the same universal primer sequence from WTA. Primer extension using TCR V-region primers and targeted PCR amplification results in a 3' barcoded single-cell CDR3-enriched library that can be sequenced with custom sequencing primers. Coupled with 3' scRNA-seq of the same WTA, this method enables simultaneous analysis of single-cell transcriptomes and TCR sequences which can help interpret inherent heterogeneity among antigen-specific T cells and salient disease biology. This method can be adapted to enrich other transcripts of interest from 3' and 5' barcoded WTA libraries., Comment: 57 pages excluding supplementary figures, 7 figures, 8 tables, 5 supplementary figures
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- 2022
70. Interatrial Septal Mass Secondary to Rosai-Dorfman Disease
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Abdul Hadi Butt, Mark Peterzan, Chirag Shah, Matthew Wright, Christopher A. Rinaldi, Jaswinder Gill, Stamatis Kapetanakis, and Jonathan M. Behar
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Cardiology and Cardiovascular Medicine - Published
- 2023
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71. PO-01-182 CONDUCTION SYSTEM PACING REMAINS EFFECTIVE IN PATIENTS WITH NON-CONDUCTIVE SEPTAL SCAR BUT SURVIVING PURKINJE
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Marina Strocchi, Karli Gillette, Mark K. Elliott, Nadeev Wijesuriya, Aurel Neic, Jonathan M. Behar, Vishal S. Mehta, Gernot Plank, Edward J. Vigmond, Christopher A. Rinaldi, and Steven A. Niederer
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Published
- 2023
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72. Dispersion of repolarization increases with cardiac resynchronization therapy and is associated with left ventricular reverse remodeling
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Mark K. Elliott, Marina Strocchi, Vishal S. Mehta, Nadeev Wijesuriya, Nilanka N. Mannakkara, Tom Jackson, Helder Pereira, Jonathan M. Behar, Martin J. Bishop, Steven Niederer, and Christopher A. Rinaldi
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Cardiac Resynchronization Therapy ,Heart Failure ,Electrocardiography ,Ventricular Dysfunction, Left ,Treatment Outcome ,Ventricular Remodeling ,Humans ,Arrhythmias, Cardiac ,Cardiology and Cardiovascular Medicine - Abstract
Cardiac resynchronization therapy (CRT) reduces ventricular activation times and electrical dyssynchrony, however the effect on repolarization is unclear. In this study, we sought to investigate the effect of CRT and left ventricular (LV) remodeling on dispersion of repolarization using electrocardiographic imaging (ECGi).11 patients with heart failure and electrical dyssynchrony underwent ECGi 1-day and 6-months post CRT. Reconstructed epicardial electrograms were used to create maps of activation time, repolarization time (RT) and activation recovery intervals (ARI) and calculate measures of RT, ARI and their dispersion. ARI was corrected for heart rate (cARI).Compared to baseline rhythm, LV cARI dispersion was significantly higher at 6 months (28.2 ± 7.7 vs 36.4 ± 7.2 ms; P = 0.03) but not after 1 day (28.2 ± 7.7 vs 34.4 ± 6.8 ms; P = 0.12). There were no significant differences from baseline to CRT for mean LV cARI or RT metrics. Significant LV remodeling (15% reduction in end-systolic volume) was an independent predictor of increase in LV cARI dispersion (P = 0.04) and there was a moderate correlation between the degree of LV remodeling and the relative increase in LV cARI dispersion (R = -0.49) though this was not statistically significant (P = 0.12).CRT increases LV cARI dispersion, but this change was not fully apparent until 6 months post implant. The effects of CRT on LV cARI dispersion appeared to be dependent on LV reverse remodeling, which is in keeping with evidence that the risk of ventricular arrhythmia after CRT is higher in non-responders compared to responders.
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- 2022
73. Leadless left ventricular endocardial pacing for cardiac resynchronization therapy: A systematic review and meta-analysis
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Nadeev Wijesuriya, Mark K. Elliott, Vishal Mehta, Baldeep S. Sidhu, Jonathan M. Behar, Steven Niederer, and Christopher A. Rinaldi
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Cardiac Resynchronization Therapy ,Heart Failure ,Treatment Outcome ,Physiology (medical) ,Heart Ventricles ,Humans ,Cardiac Resynchronization Therapy Devices ,Cardiology and Cardiovascular Medicine ,Ventricular Function, Left ,Endocardium - Abstract
Leadless left ventricular (LV) endocardial pacing to achieve cardiac resynchronization therapy (CRT) is a novel procedure for treatment of patients with dyssynchronous heart failure. Current evidence is limited to observational studies with small patient numbers.The purpose of this systematic review and meta-analysis was to assess the safety and efficacy of leadless LV endocardial pacing.A literature search was conducted through PubMed, EMBASE, and Cochrane databases. Mean differences (MDs) in New York Heart Association (NYHA) functional class and LV ejection fraction (LVEF) from baseline to 6 months postprocedure were combined using a random effects model. Heterogeneity was evaluated using the Cochrane Q test, IFive studies with 181 patients were included in the final analysis. Procedural success rate was 90.6%. Clinical response rate was 63%, with mean improvement in NYHA functional class of 0.43 (MD -0.43; 95% confidence interval [CI] -0.76 to -0.1; P = .01), with high heterogeneity (P.001; IThe efficacy of leadless LV endocardial pacing for CRT supports its use as a second-line therapy in patients in whom standard CRT is not possible or has been ineffective. Improvements in safety profile will facilitate widespread uptake in the treatment of these patients.
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- 2022
74. A Higher Activation Threshold of Memory CD8+ T Cells Has a Fitness Cost That Is Modified by TCR Affinity during Tuberculosis.
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Stephen M Carpenter, Cláudio Nunes-Alves, Matthew G Booty, Sing Sing Way, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
T cell vaccines against Mycobacterium tuberculosis (Mtb) and other pathogens are based on the principle that memory T cells rapidly generate effector responses upon challenge, leading to pathogen clearance. Despite eliciting a robust memory CD8+ T cell response to the immunodominant Mtb antigen TB10.4 (EsxH), we find the increased frequency of TB10.4-specific CD8+ T cells conferred by vaccination to be short-lived after Mtb challenge. To compare memory and naïve CD8+ T cell function during their response to Mtb, we track their expansions using TB10.4-specific retrogenic CD8+ T cells. We find that the primary (naïve) response outnumbers the secondary (memory) response during Mtb challenge, an effect moderated by increased TCR affinity. To determine whether the expansion of polyclonal memory T cells is restrained following Mtb challenge, we used TCRβ deep sequencing to track TB10.4-specific CD8+ T cells after vaccination and subsequent challenge in intact mice. Successful memory T cells, defined by their clonal expansion after Mtb challenge, express similar CDR3β sequences suggesting TCR selection by antigen. Thus, both TCR-dependent and -independent factors affect the fitness of memory CD8+ responses. The impaired expansion of the majority of memory T cell clonotypes may explain why some TB vaccines have not provided better protection.
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- 2016
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75. The long-term outcomes of cardiac implantable electronic devices implanted via the femoral route
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Samuel Griffiths, Jonathan M. Behar, Daniel B. Kramer, Mike T. Debney, Christopher Monkhouse, Alicia Y. Lefas, Martin Lowe, Fouad Amin, Emily Cantor, Vennela Boyalla, Nabeela Karim, Jan Till, Vias Markides, Jonathan R. Clague, and Tom Wong
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Adult ,Heart Defects, Congenital ,Male ,Technology ,Pacemaker, Artificial ,Cardiac & Cardiovascular Systems ,PERMANENT PACEMAKER IMPLANTATION ,lead implantation/extraction ,biventricular pacing ,CONTRAINDICATIONS ,CARDIOVERTER-DEFIBRILLATOR ,Engineering ,0903 Biomedical Engineering ,biventricular pacing/defibrillation ,pacemaker-bradyarrhythmia's ,Humans ,Engineering, Biomedical ,RESYNCHRONIZATION ,Aged ,Retrospective Studies ,cardiac implantable electronic devices ,lead implantation ,Science & Technology ,VEIN ,1103 Clinical Sciences ,General Medicine ,ADULTS ,Middle Aged ,defibrillation ,femoral vein ,Defibrillators, Implantable ,Cardiovascular System & Hematology ,Cardiovascular System & Cardiology ,extraction ,Female ,Electronics ,Cardiology and Cardiovascular Medicine ,Life Sciences & Biomedicine - Abstract
BACKGROUND: Conventional superior access for cardiac implantable electronic devices (CIEDs) is not always possible and femoral CIEDs (F-CIED) are an alternative option when leadless systems are not suitable. The long-term outcomes and extraction experiences with F-CIEDs, in particular complex F-CIED (ICD/CRT devices), remain poorly understood. METHODS: Patients referred for F-CIEDs implantation between 2002 and 2019 at two tertiary centers were included. Early complications were defined as ≤30 days following implant and late complications >30 days. RESULTS: Thirty-one patients (66% male; age 56 ± 20 years; 35% [11] patients with congenital heart disease) were implanted with F-CIEDs (10 ICD/CRT and 21 pacemakers). Early complications were observed in 6.5% of patients: two lead displacements. Late complications at 6.8 ± 4.4 years occurred in 29.0% of patients. This was higher with complex F-CIED compared to simple F-CIED (60.0% vs. 14.3%, p = .02). Late complications were predominantly generator site related (n = 8, 25.8%) including seven infections/erosions and one generator migration. Eight femoral generators and 14 leads (median duration in situ seven [range 6-11] years) were extracted without complication. CONCLUSIONS: Procedural success with F-CIEDs is high with clinically acceptable early complication rates. There is a notable risk of late complications, particularly involving the generator site of complex devices following repeat femoral procedures. Extraction of chronic F-CIED in experienced centers is feasible and safe.
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- 2021
76. Takotsubo syndrome and complete heart block, which came first? A case report
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Mohammad Khurram Nadeem, Jason Leo Walsh, Simon Davies, and Jonathan M Behar
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Cardiology and Cardiovascular Medicine - Abstract
Background In 2018, the European Society of Cardiology published two consensus documents on takotsubo syndrome (TTS), which include the current consensus on nomenclature, diagnosis, management, and complications. However, little is mentioned on the association with complete heart block (CHB), except that ‘AV block [occurs in] 2.9% of cases’. Complete heart block is a recognized rare association of TTS, but causation is often unclear. Does CHB trigger TTS or vice-versa? Here, we present a case of TTS associated with CHB. Case summary An 89-year-old woman presented with a transient loss of consciousness, acute chest pain, and dyspnoea. A few days prior to this her daughter died suddenly of a myocardial infarction. On presentation, troponin levels were elevated, the electrocardiogram showed CHB with a broad QRS and an echo showed apical akinesis and ballooning. Angiographic investigation excluded significant coronary artery disease. A dual-chamber pacemaker was implanted after a brief period of temporary pacing. Ventricular function normalized during follow-up and her underlying rhythm remained CHB. Discussion Takotsubo syndrome may be triggered by both emotional and physical stressors. Complete heart block is recognized association, but causation is often unclear. In our case, a clear emotional trigger was identified suggesting the TTS may have precipitated CHB not vice versa.
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- 2021
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77. Human and Murine Clonal CD8+ T Cell Expansions Arise during Tuberculosis Because of TCR Selection.
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Cláudio Nunes-Alves, Matthew G Booty, Stephen M Carpenter, Alissa C Rothchild, Constance J Martin, Danielle Desjardins, Katherine Steblenko, Henrik N Kløverpris, Rajhmun Madansein, Duran Ramsuran, Alasdair Leslie, Margarida Correia-Neves, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
The immune system can recognize virtually any antigen, yet T cell responses against several pathogens, including Mycobacterium tuberculosis, are restricted to a limited number of immunodominant epitopes. The host factors that affect immunodominance are incompletely understood. Whether immunodominant epitopes elicit protective CD8+ T cell responses or instead act as decoys to subvert immunity and allow pathogens to establish chronic infection is unknown. Here we show that anatomically distinct human granulomas contain clonally expanded CD8+ T cells with overlapping T cell receptor (TCR) repertoires. Similarly, the murine CD8+ T cell response against M. tuberculosis is dominated by TB10.44-11-specific T cells with extreme TCRβ bias. Using a retro genic model of TB10.44-11-specific CD8+ Tcells, we show that TCR dominance can arise because of competition between clonotypes driven by differences in affinity. Finally, we demonstrate that TB10.4-specific CD8+ T cells mediate protection against tuberculosis, which requires interferon-γ production and TAP1-dependent antigen presentation in vivo. Our study of how immunodominance, biased TCR repertoires, and protection are inter-related, provides a new way to measure the quality of T cell immunity, which if applied to vaccine evaluation, could enhance our understanding of how to elicit protective T cell immunity.
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- 2015
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78. UCCE efforts improve quality of and demand for fresh produce at WIC A-50 stores
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L Kaiser, C Lamp, C Ganthavorn, L Farfan-Ramirez, M Behar, M Cantwell, and S Hardesty
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Agriculture - Abstract
In 2005, the Institute of Medicine recommended major revisions in the food packages provided by the federal Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), leading to new regulations that allow participants to purchase a wide variety of fruits and vegetables with their vouchers. In support of this policy change, UC Agriculture and Natural Resources Cooperative Extension (UCCE) developed educational materials to promote fresh produce among WIC participants and offered postharvest handling training at WIC-only stores, known as A-50 vendors, in order to improve produce quality. A survey conducted after the educational sessions found that WIC participants had increased knowledge of produce and A-50 vendors showed improved postharvest handling after the education sessions. This research demonstrates that combining nutrition education with postharvest handling curriculum can lead to a successful educational program that supports increased demand among WIC participants for fresh produce.
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- 2015
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79. Mitochondrial respiration contributes to the interferon gamma response in antigen-presenting cells
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S.M. Holland, Christopher M. Sassetti, Michael C. Kiritsy, Daniel Mott, Andrew J. Olive, Katelyn McCann, and Samuel M. Behar
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Mouse ,QH301-705.5 ,Science ,T cell ,Cell Respiration ,immunometabolism ,Antigen-Presenting Cells ,IFN gamma ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Immunological synapse ,Interferon-gamma ,Mice ,Immunology and Inflammation ,mitochondrial respiration ,medicine ,Animals ,Humans ,Interferon gamma ,Biology (General) ,Antigen-presenting cell ,Innate immune system ,CD40 ,General Immunology and Microbiology ,biology ,complex I ,General Neuroscience ,General Medicine ,Mitochondria ,Cell biology ,medicine.anatomical_structure ,Mitochondrial respiratory chain ,APC function ,biology.protein ,Medicine ,PD-L1 regulation ,Signal transduction ,Research Article ,Human ,medicine.drug - Abstract
The immunological synapse allows antigen-presenting cells (APCs) to convey a wide array of functionally distinct signals to T cells, which ultimately shape the immune response. The relative effect of stimulatory and inhibitory signals is influenced by the activation state of the APC, which is determined by an interplay between signal transduction and metabolic pathways. While pathways downstream of toll-like receptors rely on glycolytic metabolism for the proper expression of inflammatory mediators, little is known about the metabolic dependencies of other critical signals such as interferon gamma (IFNγ). Using CRISPR-Cas9, we performed a series of genome-wide knockout screens in murine macrophages to identify the regulators of IFNγ-inducible T cell stimulatory or inhibitory proteins MHCII, CD40, and PD-L1. Our multiscreen approach enabled us to identify novel pathways that preferentially control functionally distinct proteins. Further integration of these screening data implicated complex I of the mitochondrial respiratory chain in the expression of all three markers, and by extension the IFNγ signaling pathway. We report that the IFNγ response requires mitochondrial respiration, and APCs are unable to activate T cells upon genetic or chemical inhibition of complex I. These findings suggest a dichotomous metabolic dependency between IFNγ and toll-like receptor signaling, implicating mitochondrial function as a fulcrum of innate immunity.
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- 2021
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80. Author response: Mitochondrial respiration contributes to the interferon gamma response in antigen-presenting cells
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Michael C. Kiritsy, Katelyn J. McCann, Samuel M. Behar, Daniel Mott, Andrew J. Olive, Christopher M. Sassetti, and Steven M. Holland
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Immunology ,medicine ,Interferon gamma ,Biology ,Antigen-presenting cell ,Mitochondrial respiration ,medicine.drug - Published
- 2021
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81. T cell receptor repertoires associated with control and disease progression following Mycobacterium tuberculosis infection
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Munyaradzi, Musvosvi, Huang, Huang, Chunlin, Wang, Qiong, Xia, Virginie, Rozot, Akshaya, Krishnan, Peter, Acs, Abhilasha, Cheruku, Gerlinde, Obermoser, Alasdair, Leslie, Samuel M, Behar, Willem A, Hanekom, Nicole, Bilek, Michelle, Fisher, Stefan H E, Kaufmann, Gerhard, Walzl, Mark, Hatherill, Mark M, Davis, Thomas J, Scriba, and Tran, Van
- Abstract
Antigen-specific, MHC-restricted αβ T cells are necessary for protective immunity against Mycobacterium tuberculosis, but the ability to broadly study these responses has been limited. In the present study, we used single-cell and bulk T cell receptor (TCR) sequencing and the GLIPH2 algorithm to analyze M. tuberculosis-specific sequences in two longitudinal cohorts, comprising 166 individuals with M. tuberculosis infection who progressed to either tuberculosis (n = 48) or controlled infection (n = 118). We found 24 T cell groups with similar TCR-β sequences, predicted by GLIPH2 to have common TCR specificities, which were associated with control of infection (n = 17), and others that were associated with progression to disease (n = 7). Using a genome-wide M. tuberculosis antigen screen, we identified peptides targeted by T cell similarity groups enriched either in controllers or in progressors. We propose that antigens recognized by T cell similarity groups associated with control of infection can be considered as high-priority targets for future vaccine development.
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- 2021
82. Interactive visualization for scar transmurality in cardiac resynchronization therapy.
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Sabrina Reiml, Daniel Toth 0001, Maria Panayiotou, Bernhard Fahn, Rashed Karim, Jonathan M. Behar, Christopher A. Rinaldi, Reza Razavi, Kawal S. Rhode, Alexander Brost, and Peter Mountney
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- 2016
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83. Limited recognition of Mycobacterium tuberculosis-infected macrophages by polyclonal CD4 and CD8 T cells from the lungs of infected mice
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Yash R. Patankar, Rujapak Sutiwisesak, Alessandro Sette, Rocky Lai, Cecilia S. Lindestam Arlehamn, Shayla Boyce, and Samuel M. Behar
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CD4-Positive T-Lymphocytes ,0301 basic medicine ,Enzyme-Linked Immunospot Assay ,Immunology ,chemical and pharmacologic phenomena ,CD8-Positive T-Lymphocytes ,Biology ,Major histocompatibility complex ,Article ,Epitope ,Mycobacterium tuberculosis ,Interferon-gamma ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Multiplicity of infection ,Immune system ,Bacterial Proteins ,Antigen ,Animals ,Humans ,Tuberculosis ,Immunology and Allergy ,Cytotoxic T cell ,Lung ,Cells, Cultured ,Antigens, Bacterial ,Macrophages ,ELISPOT ,Vaccination ,respiratory system ,bacterial infections and mycoses ,biology.organism_classification ,Mycobacterium bovis ,3. Good health ,Mice, Inbred C57BL ,030104 developmental biology ,biology.protein ,030215 immunology - Abstract
Immune responses following Mycobacterium tuberculosis (Mtb) infection or vaccination are frequently assessed by measuring T-cell recognition of crude Mtb antigens, recombinant proteins, or peptide epitopes. We previously showed that not all Mtb-specific T cells recognize Mtb-infected macrophages. Thus, an important question is what proportion of T cells elicited by Mtb infection recognize Mtb-infected macrophages. We address this question by developing a modified elispot assay using viable Mtb-infected macrophages, a low multiplicity of infection and purified T cells. In C57BL/6 mice, CD4 and CD8 T cells were classically MHC restricted. Comparable frequencies of T cells that recognize Mtb-infected macrophages were determined using interferon-γ elispot and intracellular cytokine staining, and lung CD4 T cells more sensitively recognized Mtb-infected macrophages than lung CD8 T cells. Compared to the relatively high frequencies of T cells specific for antigens such as ESAT-6 and TB10.4, low frequencies of total pulmonary T cells elicited by aerosolized Mtb infection recognize Mtb-infected macrophages. Finally, we demonstrate that BCG vaccination elicits T cells that recognize Mtb-infected macrophages. We propose that the frequency of T cells that recognize infected macrophages could correlate with protective immunity and may be an alternative approach to measuring T-cell responses to Mtb antigens.
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- 2020
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84. PO-643-04 MULTI-SITE PACING FOR CARDIAC RESYNCHRONIZATION THERAPY: A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS
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Mark K. Elliott, Vishal Shahil Mehta, Nadeev Wijesuriya, Justin Gould, Jonathan M. Behar, Steven A. Niederer, and Christopher A. Rinaldi
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Published
- 2022
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85. West Asian sources of the Eurasian component in Ethiopians: a reassessment
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Luca Pagani, Burak Yelmen, Doron M. Behar, Ludovica Molinaro, Davide Marnetto, Toomas Kivisild, and Francesco Montinaro
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0301 basic medicine ,lcsh:Medicine ,030105 genetics & heredity ,Gene Frequency ,HISTORY ,lcsh:Science ,Phylogeny ,African Continental Ancestry Group ,education.field_of_study ,Genome ,Multidisciplinary ,ORIGIN ,Genomics ,Multidisciplinary Sciences ,ADMIXTURE ,Geography ,Science & Technology - Other Topics ,POPULATIONS ,Ethnology ,Mediterranean area ,FARMERS ,Human ,Asian Continental Ancestry Group ,Evolution ,Human Migration ,Population ,GENOMES ,Black People ,ANCESTRY ,Ethiopia ,Genetics, Population ,Humans ,Genetic Variation ,Genome, Human ,Article ,03 medical and health sciences ,Asian People ,STRATIFICATION ,Genetics ,education ,Allele frequency ,Minoan civilization ,Science & Technology ,lcsh:R ,SOUTHERN ,030104 developmental biology ,lcsh:Q ,Allele sharing - Abstract
The presence of genomic signatures of Eurasian origin in contemporary Ethiopians has been reported by several authors and estimated to have arrived in the area from 3000 years ago. Several studies reported plausible source populations for such a signature, using haplotype based methods on modern data or single-site methods on modern or ancient data. These studies did not reach a consensus and suggested an Anatolian or Sardinia-like proxy, broadly Levantine or Neolithic Levantine as possible sources. We demonstrate, however, that the deeply divergent, autochthonous African component which accounts for ~50% of most contemporary Ethiopian genomes, affects the overall allele frequency spectrum to an extent that makes it hard to control for it and, at once, to discern between subtly different, yet important, Eurasian sources (such as Anatolian or Levant Neolithic ones). Here we re-assess pattern of allele sharing between the Eurasian component of Ethiopians (here called "NAF" for Non African) and ancient and modern proxies. Our results unveil a genomic legacy that may connect the Eurasian genetic component of contemporary Ethiopians with Sea People and with population movements that affected the Mediterranean area and the Levant after the fall of the Minoan civilization. ispartof: SCIENTIFIC REPORTS vol:9 issue:1 ispartof: location:England status: published
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- 2019
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86. Impact of Immigration on Body Mass Index and Blood Pressure Among Adolescent Males and Females
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Karl Skorecki, Estela Derazne, Orit Pinhas-Hamiel, Ehud Grossman, Aya Bardugo, Gilad Twig, Dorit Tzur, Arnon Afek, Avi Itzhak, Uri Hamiel, Asaf Vivante, Amir Tirosh, Doron M. Behar, Cole D. Bendor, and Zivan Beer
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Male ,Adolescent ,Health Status ,media_common.quotation_subject ,Immigration ,Blood Pressure ,Risk Assessment ,Body Mass Index ,Young Adult ,Internal Medicine ,Humans ,Medicine ,Obesity ,Israel ,Retrospective Studies ,media_common ,business.industry ,Incidence ,Emigration and Immigration ,medicine.disease ,Black or African American ,Cross-Sectional Studies ,Blood pressure ,Jews ,Hypertension ,Multivariate Analysis ,Female ,Ethiopia ,business ,Body mass index ,Demography - Abstract
Immigration from one cultural milieu to another has been associated with a greater risk for incident cardio-metabolic morbidity among adults. In this nationwide, population-based, cross-sectional study of data recorded from 1992 to 2016, we assessed the association between body mass index and blood pressure levels among adolescent immigrants, aged 16 to 19 years, of Ethiopian origin, and their secular trend of overweight and obesity. Adolescents of Ethiopian origin were classified as Israeli-born (n=16 153) or immigrants (N=23 487), with stratification by age at immigration. Adolescents whose fathers were at least 3 generations in Israel (n=277 789) served as a comparative group. Hypertensive-range blood pressure values adjusted for age, sex, and height served as outcome. Among adolescents of Ethiopian origin, overweight and obesity (body mass index ≥85th percentile), increased by 2.5 and 4-fold in males and females, respectively, during the study period, compared with a 1.5-fold increase among native Israeli-born males and females. The odds for hypertensive-range measurements increased with the length of residence in Israel: 7.3%, 10.6%, and 14.4% among males who immigrated at ages 12 to 19, 6 to 11.9, and 0 to 5.9 years, respectively; and 11.5%, 16.7%, and 19.3%, respectively, among females. Israeli-born Ethiopians had a significantly higher risk for hypertensive-range measurements at any body mass index level compared with native Israeli-born examinees, after adjusting for sociodemographic factors and health status. In conclusion, among Ethiopian Israeli adolescents, abnormal blood pressure correlates directly with the time-lapse since immigration. Immigrant populations require targeted surveillance and appropriate intervention.
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- 2019
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87. High-voltage impedance rise; mechanism and management in patients with transvenous implantable cardioverter-defibrillators: a case series
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Jonathan M. Behar, Alex Cambridge, Christopher Monkhouse, and Anthony W.C. Chow
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medicine.medical_specialty ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Implantable cardioverter-defibrillator ,03 medical and health sciences ,0302 clinical medicine ,Lead failure ,Internal medicine ,Case report ,Medicine ,In patient ,Case Series ,030212 general & internal medicine ,Shock impedance ,Electrical impedance ,Normal range ,business.industry ,ICD ,Team meeting ,Hypertrophic cardiomyopathy ,Mean age ,medicine.disease ,Cohort ,Cardiology ,Encapsulation ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background We describe a case series of patients for a gradual rise in daily, low-voltage sub-threshold measurement (LVSM) of shock (high-voltage, HV) impedance in a group of patients with Boston Scientific implantable cardioverter-defibrillators (ICDs) and investigate the cause of the abnormality. Case summary Six patients presented with a gradual rise in HV impedance above normal range (132.5 ± 20.8 Ω). Patients were young with a mean age of 29 ± 11 years, four patients had hypertrophic cardiomyopathy, one left ventricular non-compaction, and one long QT. All lead designs were silicon body with GORE polytetrafluoroethylene (ePTFE) coated coils, and a lower true shock impedance (TSI) was seen in all cases with full output synchronized shock. We compared the rate of HV impedance rise with our historical cohort of Boston ICDs using an unpaired t-test. The change in impedance per month was significantly higher amongst our six patients when compared with our cohort of Boston Scientific ICDs (3.2 ± 1.9 Ω/month vs. 0.0008 ± 0.005 Ω/month, P Discussion There are distinct differences between TSI and LVSM. The TSI is derived from a full output shock, whilst LVSM is calculated from a small current output. These cases highlight the inaccuracies of the LVSM measurement. The gradual rise in LVSM is significantly higher than the value for TSI in these patients we propose the most likely mechanism is encapsulation fibrosis surrounding the right ventricular shock coil. Management for these patients requires vigorous testing to rule out electrical failure, and replacement maybe necessary.
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- 2019
88. Differential skewing of donor-unrestricted and γδ T cell repertoires in tuberculosis-infected human lungs
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Kaylesh J. Dullabh, Farina Karim, Rajhmun Madansein, Paul Ogongo, Samuel M. Behar, Alasdair Leslie, Adrie J. C. Steyn, and Ismael Awala
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0301 basic medicine ,Tuberculosis ,T cell ,Immunology ,Adaptive immunity ,Population ,Disease ,Biology ,03 medical and health sciences ,0302 clinical medicine ,T-Lymphocyte Subsets ,medicine ,Humans ,T-cell receptor ,education ,Lung ,Infectious disease ,education.field_of_study ,Repertoire ,Receptors, Antigen, T-Cell, gamma-delta ,Mycobacterium tuberculosis ,General Medicine ,medicine.disease ,Acquired immune system ,3. Good health ,030104 developmental biology ,medicine.anatomical_structure ,Infectious disease (medical specialty) ,030220 oncology & carcinogenesis ,Research Article - Abstract
Unconventional T cells that recognize mycobacterial antigens are of great interest as potential vaccine targets against tuberculosis (TB). This includes donor-unrestricted T cells (DURTs), such as mucosa-associated invariant T cells (MAITs), CD1-restricted T cells, and γδ T cells. We exploited the distinctive nature of DURTs and γδ T cell receptors (TCRs) to investigate the involvement of these T cells during TB in the human lung by global TCR sequencing. Making use of surgical lung resections, we investigated the distribution, frequency, and characteristics of TCRs in lung tissue and matched blood from individuals infected with TB. Despite depletion of MAITs and certain CD1-restricted T cells from the blood, we found that the DURT repertoire was well preserved in the lungs, irrespective of disease status or HIV coinfection. The TCRδ repertoire, in contrast, was highly skewed in the lungs, where it was dominated by Vδ1 and distinguished by highly localized clonal expansions, consistent with the nonrecirculating lung-resident γδ T cell population. These data show that repertoire sequencing is a powerful tool for tracking T cell subsets during disease.
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- 2019
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89. A Novel Quadripolar Active Fixation Left-Ventricular Pacing Lead for Cardiac Resynchronization Therapy
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Christopher Monkhouse, Ian Williams, Matthew G.D. Bates, Jonathan M. Behar, Amal Muthumala, Nicholas J. Linker, Carl Hayward, M Chapman, Andrew J. Turley, Anthony Chow, Andrew R. Thornley, and Matthew J Dewhurst
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medicine.medical_specialty ,Phrenic nerve stimulation ,business.industry ,medicine.medical_treatment ,Cardiac resynchronization therapy ,030204 cardiovascular system & hematology ,Ventricular pacing ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Target site ,Internal medicine ,Cardiology ,medicine ,030212 general & internal medicine ,Implant ,Vein ,Lead (electronics) ,business ,Active fixation - Abstract
Objectives This study sought to assess immediate and short-term performance of the Medtronic Attain Stability Quadripolar 4798 lead (Medtronic, Dublin, Ireland). Background Cardiac resynchronization therapy (CRT) is an established treatment for appropriately selected patients with left ventricular (LV) systolic dysfunction. The most common reason for failure to implant a lead is the lack of a suitable epicardial vein, due either to an absent vessel in the target site, an unacceptably high threshold, lead instability, phrenic nerve stimulation, or a combination of reasons. In August 2017, a novel quadripolar active fixation LV lead (Medtronic) was released. This paper reports the initial clinical experience with lead implantation and specifically immediate and short-term pacing parameters across 3 United Kingdom centers. Methods Consecutive patients eligible for CRT were deemed suitable for this lead. Immediate and short-term lead performance data regarding LV threshold, impedance, and displacement rates were collected at standard pacing checks (1 day, 5 weeks, 3 months, and 9 months post-implantation). Results CRT using this lead was attempted in 82 cases and was successful in 81 cases (98.8%). LV thresholds and impedance levels were 1.22 ± 0.75 V and 737 ± 319 Ω at implantation; 1.16 ± 0.71 V and 597 ± 218 Ω at day 1; 1.02 ± 0.48 V and 579 ± 148 Ω at week 6; 0.98 ± 0.49 V and 569 ± 133 Ω at 3 months; and 1.06 ± 0.48 V and 570 ± 140 Ω at 9 months. As of the publication of this paper, no LV lead has been displaced. Conclusions CRT using the Medtronic lead was successful in more than 98% of the patients. Short-to-medium-term data regarding lead performance and stability were excellent, with zero displacements as of the publication of this paper.
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- 2019
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90. Novel WWOX deleterious variants cause early infantile epileptic encephalopathy, severe developmental delay and dysmorphism among Yemenite Jews
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T. Lerman Sagie, M. Weisz-Hubshman, Eri Imagawa, Alvit Veber, E. Banne, Naomichi Matsumoto, H. Meirson, Gali Heimer, Dorit Lev, S. Modai, Lina Basel-Salmon, Annick Raas-Rothschild, Dina Marek-Yagel, Osnat Konen, Nechama Shalva, Concetta Bormans, R. Michaelson-Cohen, Bruria Ben-Zeev, R. Beeri, Y. Shilon, Noam Shomron, Doron M. Behar, Shay Tzur, and Naama Orenstein
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Male ,WWOX ,Yemen ,Tumor suppressor gene ,Compound heterozygosity ,03 medical and health sciences ,Exon ,0302 clinical medicine ,Intellectual Disability ,030225 pediatrics ,medicine ,Humans ,Missense mutation ,Genetic Association Studies ,Exome sequencing ,Genetics ,business.industry ,Tumor Suppressor Proteins ,General Medicine ,medicine.disease ,Phenotype ,Pedigree ,WW Domain-Containing Oxidoreductase ,Face ,Jews ,Mutation ,Pediatrics, Perinatology and Child Health ,Spinocerebellar ataxia ,Female ,Neurology (clinical) ,business ,Spasms, Infantile ,030217 neurology & neurosurgery - Abstract
The human WW Domain Containing Oxidoreductase (WWOX) gene was originally described as a tumor suppressor gene. However, recent reports have demonstrated its cardinal role in the pathogenesis of central nervous systems disorders such as epileptic encephalopathy, intellectual disability, and spinocerebellar ataxia. We report on six patients from three unrelated families of full or partial Yemenite Jewish ancestry exhibiting early infantile epileptic encephalopathy and profound developmental delay. Importantly, four patients demonstrated facial dysmorphism. Exome sequencing revealed that four of the patients were homozygous for a novel WWOX c.517-2A > G splice-site variant and two were compound heterozygous for this variant and a novel c.689A > C, p.Gln230Pro missense variant. Complementary DNA sequencing demonstrated that the WWOX c.517-2A > G splice-site variant causes skipping of exon six. A carrier rate of 1:177 was found among Yemenite Jews. We provide the first detailed description of patients harboring a splice-site variant in the WWOX gene and propose that the clinical synopsis of WWOX related epileptic encephalopathy should be broadened to include facial dysmorphism. The increased frequency of the c.517-2A > G splice-site variant among Yemenite Jews coupled with the severity of the phenotype makes it a candidate for inclusion in expanded preconception screening programs.
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- 2019
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91. Diagnosis and Treatment of Urinary Tract Complication in Crohn’s Disease: An Experience over 15 Years
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Haim Ben-Ami, Yeoshua Ginesin, Doron M Behar, Doron Fisher, Yeouda Edoute, and Alexandra Lavy
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Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
BACKGROUD: Urinary tract complications in Crohn’s disease are common but treatable, and often present diagnostic and therapeutic dilemmas.
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- 2002
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92. Indium incorporation at InxGa1-xN relaxed self-assembled nanostructures on Si substrates
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O. de Melo, M. Ramírez-López, M. Pérez-Caro, S. Gallardo-Hernández, Y.L. Casallas-Moreno, M. Sánchez, J. Ortega, G. Santana, M. Behar, Y. González, and M. López-López
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Condensed Matter Physics - Published
- 2022
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93. Cerebral protection device for transvenous lead extraction in a patient with an intracardiac shunt
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Wei Li, Tito Kabir, Samuel Griffiths, Tom Wong, and Jonathan M. Behar
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medicine.medical_specialty ,Lead extraction ,business.industry ,Extraction (chemistry) ,Intracardiac injection ,Transvenous lead ,Shunt (medical) ,Surgery ,Intracardiac shunt ,RC666-701 ,Cardiac resynchronisation therapy ,Medicine ,Diseases of the circulatory (Cardiovascular) system ,Adult congenital heart disease ,Cerebral protection ,business - Published
- 2021
94. Leadless left ventricular endocardial pacing for CRT upgrades in previously failed and high-risk patients in comparison with coronary sinus CRT upgrades
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Christophe Leclercq, Richard J. Schilling, Mauro Biffi, Benjamin Sieniewicz, Justin Gould, David Keane, Jonathan M. Behar, Martin Arnold, Igor Diemberger, Timothy R. Betts, Simon James, Sam Riahi, Jean-Claude Deharo, Andrew J. Turley, Angelo Auricchio, Anthony Chow, Pascal Defaye, Baldeep S. Sidhu, Vishal Mehta, Mark K. Elliott, Christian Butter, Pasquale Vergara, Petr Neuzil, Christopher A. Rinaldi, Lucas V.A. Boersma, Martin Seifert, Steven A. Niederer, King‘s College London, NHS Foundation Trust [London], The Royal Marsden, Oxford University Hospitals NHS Trust, University of Oxford [Oxford], Medizinische Hochschule Brandenburg Theodor Fontane / Brandenburg Medical School Theodor-Fontane (MHB Theodor Fontane), St. Antonius Hospital [Nieuwegein], Aalborg University [Denmark] (AAU), Na Homolce Hospital, Prague, Czech Republic., Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), San Raffaele Scientific Institute, Vita-Salute San Raffaele University and Center for Translational Genomics and Bioinformatics, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), St Vincent's University Hospital, Centre Hospitalier Universitaire [Grenoble] (CHU), Hôpital de la Timone [CHU - APHM] (TIMONE), St Bartholomew's Hospital, Laboratoire Traitement du Signal et de l'Image (LTSI), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), CHU Pontchaillou [Rennes], Fondazione Cardiocentro Ticino, This study was supported by the Wellcome/EPSRC Centre for Medical Engineering [WT203148/Z/16/Z]., University of Oxford, Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research (C2VN), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM), Cardiology, ACS - Heart failure & arrhythmias, Sidhu B.S., Sieniewicz B., Gould J., Elliott M.K., Mehta V.S., Betts T.R., James S., Turley A.J., Butter C., Seifert M., Boersma L.V.A., Riahi S., Neuzil P., Biffi M., Diemberger I., Vergara P., Arnold M., Keane D.T., Defaye P., Deharo J.-C., Chow A., Schilling R., Behar J.M., Leclercq C., Auricchio A., Niederer S.A., and Rinaldi C.A.
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medicine.medical_specialty ,medicine.medical_treatment ,Cardiac resynchronization therapy ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Clinical Research ,Pacing and Cardiac Resynchronization Therapy ,Physiology (medical) ,Internal medicine ,Medicine ,Humans ,AcademicSubjects/MED00200 ,WiSE-CRT system ,030212 general & internal medicine ,Prospective Studies ,Epicardial pacing ,Lead (electronics) ,Endocardium ,Coronary sinus ,Heart Failure ,Ejection fraction ,business.industry ,Coronary Sinus ,medicine.disease ,Cardiac surgery ,Dissection ,Prospective Studie ,Treatment Outcome ,Endocardial pacing ,Coronary Sinu ,Cardiology ,[SDV.IB]Life Sciences [q-bio]/Bioengineering ,Cardiology and Cardiovascular Medicine ,business ,Kidney disease ,Human - Abstract
Aims Cardiac resynchronization therapy (CRT) upgrades may be less likely to improve following intervention. Leadless left ventricular (LV) endocardial pacing has been used for patients with previously failed CRT or high-risk upgrades. We compared procedural and long-term outcomes in patients undergoing coronary sinus (CS) CRT upgrades with high-risk and previously failed CRT upgrades undergoing LV endocardial upgrades. Method and results Prospective consecutive CS upgrades between 2015 and 2019 were compared with those undergoing WiSE-CRT implantation. Cardiac resynchronization therapy response at 6 months was defined as improvement in clinical composite score (CCS) and a reduction in LV end-systolic volume (LVESV) ≥15%. A total of 225 patients were analysed; 121 CS and 104 endocardial upgrades. Patients receiving WiSE-CRT tended to have more comorbidities and were more likely to have previous cardiac surgery (30.9% vs. 16.5%; P = 0.012), hypertension (59.2% vs. 34.7%; P, Graphical Abstract
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- 2021
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95. Divorcing the Late Upper Palaeolithic demographic histories of mtDNA haplogroups M1 and U6 in Africa
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Sacha Jones, Ene Metspalu, Doron M. Behar, Erwan Pennarun, Jean-Paul Moisan, Richard Villems, Mait Metspalu, Tuuli Reisberg, Toomas Kivisild, Kivisild, Toomas [0000-0002-6297-7808], Jones, Sacha [0000-0003-0492-2662], and Apollo - University of Cambridge Repository
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Afro-Asiatic languages ,0106 biological sciences ,Evolution ,mtDNA haplogroups M1 and U6 ,Biology ,010603 evolutionary biology ,01 natural sciences ,DNA, Mitochondrial ,Haplogroup ,Coalescent theory ,Evolution, Molecular ,03 medical and health sciences ,QH359-425 ,Humans ,Clade ,Ecology, Evolution, Behavior and Systematics ,Phylogeny ,030304 developmental biology ,0303 health sciences ,Haplotype ,Bayes Theorem ,Sequence Analysis, DNA ,North Africa ,Phylogeography ,Genetics, Population ,Haplotypes ,Evolutionary biology ,Iberomaurusian ,Africa ,Biological dispersal ,Research Article ,Human mitochondrial DNA haplogroup - Abstract
Background A Southwest Asian origin and dispersal to North Africa in the Early Upper Palaeolithic era has been inferred in previous studies for mtDNA haplogroups M1 and U6. Both haplogroups have been proposed to show similar geographic patterns and shared demographic histories. Results We report here 24 M1 and 33 U6 new complete mtDNA sequences that allow us to refine the existing phylogeny of these haplogroups. The resulting phylogenetic information was used to genotype a further 131 M1 and 91 U6 samples to determine the geographic spread of their sub-clades. No southwest Asian specific clades for M1 or U6 were discovered. U6 and M1 frequencies in North Africa, the Middle East and Europe do not follow similar patterns, and their sub-clade divisions do not appear to be compatible with their shared history reaching back to the Early Upper Palaeolithic. The Bayesian Skyline Plots testify to non-overlapping phases of expansion, and the haplogroups’ phylogenies suggest that there are U6 sub-clades that expanded earlier than those in M1. Some M1 and U6 sub-clades could be linked with certain events. For example, U6a1 and M1b, with their coalescent ages of ~20,000–22,000 years ago and earliest inferred expansion in northwest Africa, could coincide with the flourishing of the Iberomaurusian industry, whilst U6b and M1b1 appeared at the time of the Capsian culture. Conclusions Our high-resolution phylogenetic dissection of both haplogroups and coalescent time assessments suggest that the extant main branching pattern of both haplogroups arose and diversified in the mid-later Upper Palaeolithic, with some sub-clades concomitantly with the expansion of the Iberomaurusian industry. Carriers of these maternal lineages have been later absorbed into and diversified further during the spread of Afro-Asiatic languages in North and East Africa.
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- 2021
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96. A multicenter prospective randomized controlled trial of cardiac resynchronization therapy guided by invasive dP/dt
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Shoaib Hamid, Janet M. McComb, Pier D. Lambiase, Shaumik Adhya, Francisco Leyva, Giovanni Perego, Simon Claridge, Reza Razavi, Vishal Mehta, Mark K. Elliott, Ravi Kamdar, Paolo Della Bella, J.R. Paisey, Jonathan M. Behar, C. Aldo Rinaldi, Manav Sohal, Timothy R. Betts, Tom Jackson, and Steven A. Niederer
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medicine.medical_specialty ,Haemodynamic response ,medicine.medical_treatment ,Cardiac resynchronization therapy ,Heart failure ,Acute hemodynamic response ,Targeted lead placement ,law.invention ,Clinical ,Randomized controlled trial ,law ,Internal medicine ,medicine ,Clinical endpoint ,Devices ,Diseases of the circulatory (Cardiovascular) system ,Reverse remodeling ,Coronary sinus ,business.industry ,Mean age ,LV reverse remodeling ,medicine.disease ,RC666-701 ,Cardiology ,business - Abstract
Background: No periprocedural metric has demonstrated improved cardiac resynchronization therapy (CRT) outcomes in a multicenter setting. Objective: We sought to determine if left ventricular (LV) lead placement targeted to the coronary sinus (CS) branch generating the best acute hemodynamic response (AHR) results in improved outcomes at 6 months. Methods: In this multicenter randomized controlled trial, patients were randomized to guided CRT or conventional CRT. Patients in the guided arm had LV dP/dtmax measured during biventricular (BIV) pacing. Target CS branches were identified and the final LV lead position was the branch with the best AHR and acceptable threshold values. The primary endpoint was the proportion of patients with a reduction in LV end-systolic volume (LVESV) of ≥15% at 6 months. Results: A total of 281 patients were recruited across 12 centers. Mean age was 70.8 ± 10.9 years and 54% had ischemic etiology. Seventy-three percent of patients in the guided arm demonstrated a reduction in LVESV of ≥15% at 6 months vs 60% in the conventional arm (P = .02). Patients with AHR ≥ 10% were more likely to demonstrate a reduction of ESV ≥ 15% (84% of patients with an AHR ≥10% vs 28% with an AHR
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- 2021
97. Tissue-resident-like CD4+ T cells secreting IL-17 control Mycobacterium tuberculosis in the human lung
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Alessandra Nardin, Rajhmun Madansein, Amanda Ardain, Khadija Khan, Kaylesh J. Dullabh, Alveera Singh, Taryn Naidoo, Alessandro Sette, Farina Karim, Samuel M. Behar, Alasdair Leslie, Paul T. Elkington, Liku B. Tezera, Duran Ramsuran, Michael G. Fehlings, Abigail Ngoepe, Paul Ogongo, Cecilia S. Lindestam Arlehamn, Henrik N. Kløverpris, Shepherd Nhamoyebonde, Adrie J. C. Steyn, and Boon Heng Lee
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0301 basic medicine ,CD4-Positive T-Lymphocytes ,Male ,Tuberculosis ,Immunology ,Interleukin-1beta ,T cells ,Disease ,Nitric Oxide ,Mycobacterium tuberculosis ,03 medical and health sciences ,0302 clinical medicine ,Bacterial infections ,medicine ,Humans ,Lung ,Tuberculosis, Pulmonary ,Infectious disease ,biology ,Interleukin-17 ,General Medicine ,respiratory system ,biology.organism_classification ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,Infectious disease (medical specialty) ,030220 oncology & carcinogenesis ,Granuloma ,Interleukin-2 ,Female ,Interleukin 17 ,CD8 ,Research Article - Abstract
T cell immunity is essential for the control of tuberculosis (TB), an important disease of the lung, and is generally studied in humans using peripheral blood cells. Mounting evidence, however, indicates that tissue-resident memory T cells (Trms) are superior at controlling many pathogens, including Mycobacterium tuberculosis (M. tuberculosis), and can be quite different from those in circulation. Using freshly resected lung tissue, from individuals with active or previous TB, we identified distinct CD4+and CD8+ Trm-like clusters within TB-diseased lung tissue that were functional and enriched for IL-17–producing cells. M. tuberculosis–specific CD4+ T cells producing TNF-α, IL-2, and IL-17 were highly expanded in the lung compared with matched blood samples, in which IL-17+ cells were largely absent. Strikingly, the frequency of M. tuberculosis–specific lung T cells making IL-17, but not other cytokines, inversely correlated with the plasma IL-1β levels, suggesting a potential link with disease severity. Using a human granuloma model, we showed the addition of either exogenous IL-17 or IL-2 enhanced immune control of M. tuberculosis and was associated with increased NO production. Taken together, these data support an important role for M. tuberculosis–specific Trm-like, IL-17–producing cells in the immune control of M. tuberculosis in the human lung.
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- 2021
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98. iNKT cell production of GM-CSF controls Mycobacterium tuberculosis.
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Alissa C Rothchild, Pushpa Jayaraman, Cláudio Nunes-Alves, and Samuel M Behar
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Immunologic diseases. Allergy ,RC581-607 ,Biology (General) ,QH301-705.5 - Abstract
Invariant natural killer T (iNKT) cells are activated during infection, but how they limit microbial growth is unknown in most cases. We investigated how iNKT cells suppress intracellular Mycobacterium tuberculosis (Mtb) replication. When co-cultured with infected macrophages, iNKT cell activation, as measured by CD25 upregulation and IFNγ production, was primarily driven by IL-12 and IL-18. In contrast, iNKT cell control of Mtb growth was CD1d-dependent, and did not require IL-12, IL-18, or IFNγ. This demonstrated that conventional activation markers did not correlate with iNKT cell effector function during Mtb infection. iNKT cell control of Mtb replication was also independent of TNF and cell-mediated cytotoxicity. By dissociating cytokine-driven activation and CD1d-restricted effector function, we uncovered a novel mediator of iNKT cell antimicrobial activity: GM-CSF. iNKT cells produced GM-CSF in vitro and in vivo in a CD1d-dependent manner during Mtb infection, and GM-CSF was both necessary and sufficient to control Mtb growth. Here, we have identified GM-CSF production as a novel iNKT cell antimicrobial effector function and uncovered a potential role for GM-CSF in T cell immunity against Mtb.
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- 2014
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99. IFNγ and iNOS-mediated alterations in the bone marrow and thymus and its impact onMycobacterium avium-induced thymic atrophy
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Claudia Nobrega, Rita Melo-Miranda, Daniela de Sá Calçada, Margarida Borges, Samuel M. Behar, Palmira Barreira-Silva, Susana Roque, Margarida Correia-Neves, Rui Appelberg, and Cláudia Serre-Miranda
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0303 health sciences ,T cell ,Biology ,Molecular biology ,3. Good health ,03 medical and health sciences ,Thymocyte ,0302 clinical medicine ,medicine.anatomical_structure ,Apoptosis ,Precursor cell ,T cell differentiation ,medicine ,Interferon gamma ,Bone marrow ,Progenitor cell ,030304 developmental biology ,030215 immunology ,medicine.drug - Abstract
Disseminated infection with the high virulence strain ofMycobacterium avium25291 lead to progressive thymic atrophy. We previously uncovered thatM. avium-induced thymic atrophy is due to increased levels of glucocorticoids synergizing with nitric oxide (NO) produced by interferon gamma (IFNγ) activated macrophages. Where and how these mediators are playing, was yet to be understood. We hypothesized that IFNγ and NO might be affecting bone marrow (BM) T cell precursors and/or T cell differentiation in the thymus. We show thatM. aviuminfection causes a reduction on the percentage of lymphoid-primed multipotent progenitors (LMPP) and common lymphoid progenitors (CLP). Additionally, BM precursors from infected mice are unable to reconstitute thymi of RAGKO mice in an IFNγ-dependent way. Thymi from infected mice presents a NO-dependent inflammation. When transplanted under the kidney capsule of non-infected mice, thymic stroma from infected mice is unable to sustain T cell differentiation. Finally, we observed increased thymocyte death via apoptosis after infection, independent of both IFNγ and iNOS, and a decrease on activated caspase-3 positive thymocytes, that was not observed in the absence of iNOS expression. Together our data suggests thatM. avium-induced thymic atrophy results from a combination of impairments, mediated by IFNγ and NO, affecting different steps of T cell differentiation from T cell precursor cells in the BM to the thymic stroma and thymocytes.
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- 2021
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100. A multi-center experience of ablation index for evaluating lesion delivery in typical atrial flutter
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Anthony Chow, Edd Maclean, Mehul Dhinoja, Vias Markides, Mark J. Earley, Ron Ben Simon, Jonathan M. Behar, Pier D. Lambiase, Fakhar Khan, Syed Ahsan, Tom Wong, James Rosengarten, Rui Providência, Ross J. Hunter, Gurpreet Dhillon, and Richard Ang
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Male ,Cavotricuspid isthmus ,medicine.medical_treatment ,Catheter ablation ,030204 cardiovascular system & hematology ,Inferior vena cava ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,Typical atrial flutter ,medicine ,Humans ,Sinus rhythm ,030212 general & internal medicine ,Aged ,business.industry ,General Medicine ,Ablation ,medicine.disease ,medicine.vein ,Atrial Flutter ,Catheter Ablation ,Female ,Tricuspid Valve ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,Nuclear medicine ,business ,Atrial flutter - Abstract
BACKGROUND Anatomical studies demonstrate significant variation in cavotricuspid isthmus (CTI) architecture. METHODS Thirty-eight patients underwent CTI ablation at two tertiary centers. Operators delivered 682 lesions with a target ablation index (AI) of 600 Wgs. Ablation parameters were recorded every 10-20 ms. Post hoc, Visitags were trisected according to CTI position: inferior vena cava (IVC), middle (Mid), or ventricular (V) lesions. RESULTS There were no complications. 92.1% of patients (n = 35) remained in sinus rhythm after 14.6 ± 3.4 months. For the whole CTI, peak AI correlated with mean impedance drop (ID) (R2 = 0.89, p
- Published
- 2021
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